InternPractice — Always a Step Ahead

Medicinal Forms

There can be variation in the licensing of different medicines containing the same drug. Solution for injection EXCIPIENTS: May contain Benzyl alcohol ▶Fibro-Vein (STD Pharmaceutical Products Ltd) Sodium tetradecyl sulfate 2 mg per 1 ml Fibrovein 0.2% solution for injection 5ml vials | 10 vial P £73.61 Sodium tetradecyl sulfate 5 mg per 1 ml Fibrovein 0.5% solution for injection 2ml ampoules | 5 ampoule P £18.93 Sodium tetradecyl sulfate 10 mg per 1 ml Fibrovein 1% solution for injection 2ml ampoules | 5 ampoule P £22.61 Sodium tetradecyl sulfate 30 mg per 1 ml Fibrovein 3% solution for injection 2ml ampoules | 5 ampoule P £33.65 Fibrovein 3% solution for injection 5ml vials | 10 vial P £166.66 Chapter 3 Respiratory system CONTENTS Airways disease, obstructive page 251 Allergic conditions Angioedema 2.1 Conditions affecting sputum viscosity Cystic ﬁbrosis 3.1 Respiratory system, drug delivery Inhalation This route delivers the drug directly to the airways; the dose required is smaller than when given by mouth and side- effects are reduced. Inhaler devices These include pressurised metered-dose inhalers, breath- actuated inhalers, and dry powder inhalers. Many patients can be taught to use a pressurised metered-dose inhaler effectively but some patients, particularly the elderly and children, ﬁnd them difﬁcult to use. Spacer devices can help such patients because they remove the need to co-ordinate actuation with inhalation. Dry powder inhalers may be useful in adults and children over 5 years who are unwilling or unable to use a pressurised metered-dose inhaler. Alternatively, breath-actuated inhalers are suitable for adults and older children provided they can use the device effectively. g In adults with stable asthma, a pressurised metered- dose inhaler with or without a spacer is as effective as any other hand-held inhaler; a dry-powder inhaler may still be preferred. A spacer should always be used if the patient is on a high dose of inhaled corticosteroid. In adults with mild or moderate acute asthma attacks, a pressurised metered-dose inhaler with a spacer is at least as effective as nebulisation. h On changing from a pressurised metered-dose inhaler to a dry powder inhaler, patients may notice a lack of sensation in the mouth and throat previously associated with each actuation. Coughing may also occur. g The patient should be instructed carefully on the use of the inhaler. It is important to check that the inhaler continues to be used correctly because inadequate inhalation technique may be mistaken for a lack of response to the drug. The number and different types of inhalers given to a patient should be minimised. To help reduce confusion and ensure patients receive inhalers they have been given training for, specify brand and inhaler when prescribing. h For more information on delivery systems used in the management of COPD, see Chronic obstructive pulmonary disease p. 256. MHRA/CHM advice: Pressurised metered dose inhalers (pMDI): risk of airway obstruction from aspiration of loose objects (July 2018) The MHRA have received reports of patients who have inhaled objects into the back of the throat—in some cases objects were aspirated, causing airway obstruction. Patients should be reminded to remove the mouthpiece cover fully, shake the device and check that both the outside and inside of the mouthpiece are clear and undamaged before inhaling Respiratory system Cough and congestion page 311 Idiopathic pulmonary fibrosis Respiratory depression, respiratory distress syndrome and apnoea a dose, and to store the inhaler with the mouthpiece cover on. Spacer devices Spacer devices remove the need for coordination between actuation of a pressurised metered-dose inhaler and inhalation. The spacer device reduces the velocity of the aerosol and subsequent impaction on the oropharynx and allows more time for evaporation of the propellant so that a larger proportion of the particles can be inhaled and deposited in the lungs. Spacer devices are particularly useful for patients with poor inhalation technique, for children, for patients requiring high doses of inhaled corticosteroids, for nocturnal asthma, and for patients prone to candidiasis with inhaled corticosteroids. It is important to prescribe a spacer device that is compatible with the metered-dose inhaler, see devices below. Spacer devices should not be regarded as interchangeable; patients should be advised not to switch between spacer devices. Use and care of spacer devices Patients should inhale from the spacer device as soon as possible after actuation because the drug aerosol is very short-lived; single-dose actuation is recommended. Tidal breathing is as effective as single breaths. The device should be cleaned once a month by washing in mild detergent and then allowed to dry in air without rinsing; the mouthpiece should be wiped clean of detergent before use. Some manufacturers recommend more frequent cleaning, but this should be avoided since any electrostatic charge may affect drug delivery. Spacer devices should be replaced every 6–12 months. Respiratory drug delivery, nebulisers Solutions for nebulisation used in severe or life-threatening asthma attacks are administered over 5–10 minutes from a nebuliser, usually driven by oxygen. g Patients with a severe attack of asthma should preferably have oxygen during nebulisation since beta2 agonists can increase arterial hypoxaemia. However, the absence of supplemental oxygen should not delay treatment. h A nebuliser converts a solution of a drug into an aerosol for inhalation. It is used to deliver higher doses of drug to the airways than is usual with standard inhalers. The main indications for use of a nebuliser are to deliver: . a beta2 agonist or ipratropium bromide p. 261 to a patient with an acute exacerbation of asthma or of chronic obstructive pulmonary disease; . a beta2 agonist, corticosteroid, or ipratropium bromide on a regular basis to a patient with severe asthma or reversible airways obstruction when the patient is unable to use other inhalational devices; . an antibiotic (such as colistimethate sodium p. 588) or a mucolytic to a patient with cystic ﬁbrosis; . Budesonide p. 273 or adrenaline/epinephrine p. 236 to a child with severe croup; . Pentamidine isetionate p. 637 for the prophylaxis and treatment of pneumocystis pneumonia. Before prescribing a nebuliser, a home trial should Respiratory system preferably be undertaken to monitor response for up to 2 weeks on standard treatment and up to 2 weeks on nebulised treatment. If prescribed, patients must: . have clear instructions from a doctor, specialist nurse, physiotherapist, or pharmacist on the use of the nebuliser (including maintenance and cleaning) and on peak-ﬂow monitoring; . be instructed not to treat acute attacks at home without also seeking help; . have regular follow up by a doctor, specialist nurse or physiotherapist after about 1 month and annually thereafter. The proportion of a nebuliser solution that reaches the lungs depends on the type of nebuliser and although it can be as high as 30%, it is more frequently close to 10% and sometimes below 10%. The remaining solution is left in the nebuliser as residual volume or is deposited in the mouthpiece and tubing. The extent to which the nebulised solution is deposited in the airways or alveoli depends on the droplet size, pattern of breath inhalation, and condition of the lung. Droplets with a mass median diameter of 1–5 microns are deposited in the airways and are therefore appropriate for asthma, whereas a particle size of 1–2 microns is needed for alveolar deposition of pentamidine isetionate p. 637 to combat pneumocystis infection. The type of nebuliser is therefore chosen according to the deposition required and according to the viscosity of the solution. Jet nebulisers Jet nebulisers are more widely used than ultrasonic nebulisers. Most jet nebulisers require an optimum gas ﬂow rate of 6–8 litres/minute and in hospital can be driven by piped air or oxygen; in acute asthma the nebuliser should be driven by oxygen. Domiciliary oxygen cylinders do not provide an adequate ﬂow rate therefore an electrical compressor is required for domiciliary use. For patients at risk of hypercapnia, such as those with chronic obstructive pulmonary disease, oxygen can be dangerous and the nebuliser should be driven by air. If oxygen is required, it should be given simultaneously by nasal cannula. Tubing The Department of Health has reminded users of the need to use the correct grade of tubing when connecting a nebuliser to a medical gas supply or compressor. Ultrasonic nebulisers Ultrasonic nebulisers produce an aerosol by ultrasonic vibration of the drug solution and therefore do not require a gas ﬂow; they are not suitable for the nebulisation of some drugs, such as dornase alfa p. 308 and nebulised suspensions. Nebuliser diluent Nebulisation may be carried out using an undiluted nebuliser solution or it may require dilution beforehand. The usual diluent is sterile sodium chloride 0.9% (physiological saline). In England and Wales nebulisers and compressors are not available on the NHS (but they are free of VAT); some nebulisers (but not compressors) are available on form GP10A in Scotland (for details consult Scottish Drug Tariff). Oral The oral route is used when administration by inhalation is not possible. Systemic side-effects occur more frequently when a drug is given orally rather than by inhalation. Drugs given by mouth for the treatment of asthma include corticosteroids, theophylline p. 288, and leukotriene receptor antagonists. Parenteral g Drugs such as beta2 agonists, corticosteroids, and aminophylline p. 287 can be given by injection in severe acute and life-threatening asthma when administration by nebulisation is inadequate or inappropriate. If the patient is being treated in the community, urgent transfer to hospital should be arranged. h Peak flow meters When used in addition to symptom-based monitoring, peak ﬂow monitoring has not been proven to improve asthma control in either adults or children, however measurement of peak ﬂow may be of beneﬁt in adult patients who are ‘poor perceivers’ and hence slow to detect deterioration in their asthma, and for those with more severe asthma. When peak ﬂow meters are used, patients must be given clear guidelines as to the action they should take if their peak ﬂow falls below a certain level. Patients can be encouraged to adjust some of their own treatment (within speciﬁed limits) according to changes in peak ﬂow rate. Peak ﬂow charts should be issued to patients where appropriate, and are available to purchase from: 3M Security Print and Systems Limited. Gorse Street, Chadderton, Oldham, OL9 9QH. Tel: 0845 610 1112 GP practices can obtain supplies through their Area Team stores. NHS Hospitals can order supplies from www.nhsforms.co. uk/ or by emailing nhsforms@mmm.com. In Scotland, peak ﬂow charts can be obtained by emailing stockorders.dppas@apsgroup.co.uk. NICE decisions Inhaler devices for children under 5 years with chronic asthma (August 2000) NICE TA10 When selecting inhaler devices for children under 5 years with chronic asthma, a child’s needs and likelihood of good compliance should govern the choice of inhaler and spacer device; only then should cost be considered. . corticosteroid and bronchodilator therapy should be delivered by pressurised metered-dose inhaler and spacer device, with a facemask if necessary; . if this is not effective, and depending on the child’s condition, nebulised therapy may be considered and, in children over 3 years, a dry powder inhaler may also be considered. www.nice.org.uk/TA10 Inhaler devices for children 5–15 years with chronic asthma (March 2002) NICE TA38 When selecting inhaler devices for children between 5–15 years with chronic asthma, a child’s needs, ability to develop and maintain effective technique, and likelihood of good compliance should govern the choice of inhaler and spacer device; only then should cost be considered. . corticosteroid therapy should be routinely delivered by a pressurised metered-dose inhaler and spacer device; . for other inhaled drugs, particularly bronchodilators, choice should be made from a wider range of devices after careful consideration; . children and their carers should be trained in the use of the chosen device; suitability of the device should be reviewed at least annually. Inhaler technique and compliance should be monitored. www.nice.org.uk/TA38 Airways disease, obstructive Asthma, chronic Description of condition Asthma is a common chronic inﬂammatory condition of the airways, associated with airway hyperresponsiveness and variable airﬂow obstruction. The most frequent symptoms of asthma are cough, wheeze, chest tightness, and breathlessness. Asthma symptoms vary over time and in intensity and can gradually or suddenly worsen, provoking an acute asthma attack that, if severe, may require hospitalisation. Asthma-COPD overlap syndrome (ACOS) is characterised by persistent airﬂow limitation displaying features of both asthma and COPD. Aims of treatment The aim of treatment is to achieve control of asthma. Complete control of asthma is deﬁned as no daytime symptoms, no night-time awakening due to asthma, no asthma attacks, no need for rescue medication, no limitations on activity including exercise, normal lung function (in practical terms forced expiratory volume in 1 second (FEV1) and/or peak expiratory ﬂow (PEF) > 80% predicted or best), and minimal side-effects from treatment. In clinical practice, patients may choose to balance the aims of asthma management against the potential side-effects or inconvenience of taking medication necessary to achieve perfect control. Lifestyle changes g Weight loss in overweight patients may lead to an improvement in asthma symptoms. Patients with asthma and parents of children with asthma should be advised about the dangers of smoking, to themselves and to their children, and be offered appropriate support to stop smoking. h For further information, see Smoking cessation p. 520. g Breathing exercise programmes (including physiotherapist-taught methods and audiovisual programmes), can be offered to adults as an adjuvant to drug treatment to improve quality of life and reduce symptoms. h Management g A stepwise approach aims to stop symptoms quickly and to improve peak ﬂow. Treatment should be started at the level most appropriate to initial severity of asthma. The aim is to achieve early control and to maintain it by stepping up treatment as necessary and decreasing treatment when control is good. Before initiating a new drug or adjusting treatment, consider whether the diagnosis is correct, check adherence and inhaler technique, and eliminate trigger factors for acute attacks. A self-management programme comprising of a written personalised action plan and education should be offered to all patients with asthma (and/or their family or carers), and should be supported with regular review by a healthcare professional. h For information on devices used in the management of asthma, see Respiratory system, drug delivery p. 249. Recommendations on the management of chronic asthma from the National Institute for Health and Care Excellence (NICE)—Asthma: diagnosis, monitoring and chronic asthma management guidelines (NG80, November 2017), and British Thoracic Society (BTS) and Scottish Intercollegiate Guidelines Network (SIGN)—British guideline on the management of asthma (SIGN 158, July 2019) differ signiﬁcantly. Recommendations in BNF publications are based on NICE guidelines, and differences with BTS/SIGN (2019) have been highlighted. For information on the management of patients during the COVID-19 pandemic, see COVID-19 p. 656. Respiratory system Adult NICE (2017) treatment recommendations for adults apply to patients aged 17 years and over. BTS/SIGN (2019) treatment recommendations for adults apply to patients aged over 12 years. Intermittent reliever therapy g Start an inhaled short-acting beta2 agonist (such as salbutamol p. 267 or terbutaline sulfate p. 269), to be used as required in all patients with asthma. For those with infrequent short-lived wheeze, occasional use of reliever therapy may be the only treatment required. Patients using more than one short-acting beta2 agonist inhaler device a month should have their asthma urgently assessed and action taken to improve poorly controlled asthma. h Regular preventer (maintenance) therapy NICE (2017) deﬁne inhaled corticosteroid (ICS) doses for adults as low, moderate, or high. BTS/SIGN (2019) instead deﬁne ICS doses for adults as low, medium or high (refer to individual guidelines for ICS dosing information). g A low-dose of ICS should be started as maintenance therapy in patients who present with any one of the following features: using an inhaled short-acting beta2 agonist three times a week or more, symptomatic three times a week or more, or waking at night due to asthma symptoms at least once a week. BTS/SIGN (2019) also recommend initiation in patients who have had an asthma attack in the last 2 years, and starting an ICS at a dose appropriate to the severity of asthma. BTS/SIGN (2019) recommend that inhaled corticosteroids (except ciclesonide p. 276) should initially be taken twice daily, however the same total daily dose taken once a day, can be considered in patients with milder disease if good or complete control of asthma is established. The dose of ICS should be adjusted over time to the lowest effective dose at which control of asthma is maintained. BTS/SIGN (2019) recommend the prescribing of inhalers by brand. h Initial add-on therapy g If asthma is uncontrolled on a low-dose of ICS as maintenance therapy, a leukotriene receptor antagonist (LTRA—such as montelukast p. 284) should be offered in addition to the ICS, and the response to treatment reviewed in 4 to 8 weeks. BTS/SIGN (2019) instead recommend a long-acting beta2 agonist (LABA—such as salmeterol p. 266 or formoterol fumarate p. 264) as initial add-on therapy to low-dose ICS if asthma is uncontrolled. This can be given as either a ﬁxed- dose ICS and LABA regimen, or a MART regimen (Maintenance And Reliever Therapy—a combination of an ICS and a fast-acting LABA such as formoterol in a single inhaler, see beclometasone with formoterol p. 272 and budesonide with formoterol p. 274). Combination inhalers containing both a LABA and an ICS are recommended to improve adherence, and ensure that the LABA is not taken alone without the ICS. BTS/SIGN (2019) also recommend that a MART regimen should be considered in patients with a history of asthma attacks on a medium-dose ICS alone, or on a ﬁxed-dose ICS and LABA regimen. h Additional controller therapies g If asthma is uncontrolled on a low-dose of ICS and a LTRA as maintenance therapy, a LABA in combination with the ICS should be offered with or without continued LTRA treatment, depending on the response achieved from the LTRA. If asthma remains uncontrolled, offer to change the ICS and LABA maintenance therapy to a MART regimen, with a low- dose of ICS as maintenance. See beclometasone with formoterol p. 272 and budesonide with formoterol p. 274. If asthma remains uncontrolled on a MART regimen with a low-dose of ICS as maintenance with or without a LTRA, Respiratory system consider increasing to a moderate-dose of ICS (either continuing a MART regimen, or changing to a ﬁxed-dose regimen of an ICS and a LABA with a short-acting beta2 agonist as reliever therapy). If asthma is still uncontrolled in patients on a moderate- dose of ICS as maintenance with a LABA (either as a MART or a ﬁxed-dose regimen), with or without a LTRA, consider the following options: . Increasing the ICS dose to a high-dose as maintenance (this should only be offered as part of a ﬁxed-dose regimen with a short-acting beta2 agonist used as reliever therapy), or . A trial of an additional drug, for example, a long-acting muscarinic receptor antagonist (such as tiotropium p. 262) or modiﬁed-release theophylline p. 288, or . Seeking advice from an asthma specialist. BTS/SIGN (2019) instead recommend that if the patient is gaining some beneﬁt from addition of a LABA but control remains inadequate, the LABA should be continued and either the dose of ICS be increased to a medium-dose (if not already on this dose), or a LTRA be added. If there is no response to the LABA, consider discontinuing it and either increasing the dose of the ICS to a medium-dose (if not already on this dose), or adding in a LTRA. BTS/SIGN (2019) recommend that all patients whose asthma is not adequately controlled on recommended initial add-on therapy or additional controller therapies, should be referred for specialist asthma care. h High-dose ICS and further add-on treatment (specialist therapies) g Under specialist care, BTS/SIGN (2019) recommend that if asthma control remains inadequate on a medium- dose of ICS, plus a LABA or LTRA, the following interventions can be considered: . Increasing the ICS to a high-dose—with high doses of ICS via a pressurised metered dose inhaler (pMDI) a spacer should be used, or . Adding a LTRA (if not already tried), or modiﬁed-release theophylline p. 288, or tiotropium p. 262. If a trial of a further add-on treatment is ineffective, stop the drug (or in the case of increased dose of ICS, reduce to the original dose). h Continuous or frequent use of oral corticosteroids (specialist therapies) g Under specialist care, BTS/SIGN (2019) recommend adding a regular oral corticosteroid (prednisolone p. 716) at the lowest dose to provide adequate control in patients with very severe asthma uncontrolled on a high-dose ICS, and who have also tried (or are still receiving) a LABA, LTRA, tiotropium p. 262, or modiﬁed-release theophylline p. 288. h For information on the general use and side effects of corticosteroids, see Corticosteroids, general use p. 707. For information on the cessation of oral corticosteroid treatment, see Treatment cessation for systemic corticosteroids (such as prednisolone). Monoclonal antibodies and immunosuppressants (specialist therapies) g Under specialist initiation, BTS/SIGN (2019) recommend that monoclonal antibodies such as omalizumab p. 282 (for severe persistent allergic asthma), mepolizumab p. 281, benralizumab p. 281 and reslizumab p. 283 (in adults for severe eosinophilic asthma), and immunosuppressants such as methotrexate p. 963 [unlicensed], may be considered in patients with severe asthma to achieve control and reduce the use of oral corticosteroids. h See National funding/access decisions for omalizumab p. 282, mepolizumab p. 281, reslizumab p. 283, and benralizumab. Child aged over 5 years For children aged over 5 years, NICE (2017) treatment recommendations for children apply to children aged 5–16 years, and adult treatment recommendations apply to those aged 17 years and over. Whereas, for children aged over 5 years, BTS/SIGN (2019) treatment recommendations for children apply to children aged 5–12 years, and adult treatment recommendations apply to those aged over 12 years. Intermittent reliever therapy g Start an inhaled short-acting beta2 agonist (such as salbutamol p. 267 or terbutaline sulfate p. 269), to be used as required in all children with asthma. For those with infrequent short-lived wheeze, occasional use of reliever therapy may be the only treatment required. Children using more than one short-acting beta2 agonist inhaler device a month should have their asthma urgently assessed and action taken to improve poorly controlled asthma. h Regular preventer (maintenance) therapy NICE (2017) deﬁne inhaled corticosteroid (ICS) doses for children (aged 5–16 years) as paediatric low, moderate, or high. BTS/SIGN (2019) instead deﬁne ICS doses for children (aged 5–12 years) as very low, low, or medium, and for children aged over 12 years as low, medium or high (refer to individual guidelines for ICS dosing information). g A paediatric low-dose of ICS should be started as maintenance therapy in children who present with any one of the following features: using an inhaled short-acting beta2 agonist three times a week or more, symptomatic three times a week or more, or waking at night due to asthma symptoms at least once a week. BTS/SIGN (2019) instead recommend starting a very low- dose (child aged 5–12 years) or a low-dose (child aged over 12 years) of ICS in children presenting with any one of the following features: using an inhaled short-acting beta2 agonist three times a week or more, symptomatic three times a week or more, waking at night due to asthma symptoms at least once a week, or have had an asthma attack in the last 2 years, and starting an ICS at a dose appropriate to the severity of asthma. BTS/SIGN (2019) recommend that inhaled corticosteroids (except ciclesonide p. 276) should initially be taken twice daily, however the same total daily dose taken once a day, can be considered in patients with milder disease if good or complete control of asthma is established. The dose of ICS should be adjusted over time to the lowest effective dose at which control of asthma is maintained. BTS/SIGN (2019) recommend the prescribing of inhalers by brand. h Initial add-on therapy g If asthma is uncontrolled on a paediatric low-dose of ICS as maintenance therapy, consider a leukotriene receptor antagonist (LTRA—such as montelukast p. 284) in addition to the ICS, and review the response to treatment in 4 to 8 weeks. BTS/SIGN (2019) instead recommend a long-acting beta2 agonist (LABA—such as salmeterol p. 266 or formoterol fumarate p. 264) as initial add-on therapy to low-dose ICS if asthma is uncontrolled in children aged over 12 years. This can be given as either a ﬁxed-dose ICS and LABA regimen, or a MART regimen (Maintenance And Reliever Therapy—a combination of an ICS and a fast-acting LABA such as formoterol in a single inhaler, see budesonide with formoterol p. 274). Combination inhalers containing both a LABA and an ICS are recommended to improve adherence, and ensure that the LABA is not taken alone without the ICS. BTS/SIGN (2019) also recommend that a MART regimen should be considered in children aged over 12 years with a history of asthma attacks on a medium-dose ICS alone, or on a ﬁxed-dose ICS and LABA regimen. In children aged 5–12 years, BTS/SIGN (2019) recommend the addition of either a LABA or a LTRA, as initial add-on therapy to very low-dose ICS if asthma is uncontrolled. h Additional controller therapies g If asthma is uncontrolled on a paediatric low-dose of ICS and a LTRA as maintenance therapy, consider discontinuation of the LTRA and initiation of a LABA in combination with the ICS. If asthma remains uncontrolled on a paediatric low-dose of ICS and a LABA as maintenance therapy, consider changing to a MART regimen (Maintenance And Reliever Therapy—a combination of an ICS and fast-acting LABA such as formoterol in a single inhaler) with a paediatric low- dose of ICS as maintenance. See budesonide with formoterol p. 274 [not licensed in all age groups]. If asthma remains uncontrolled on a MART regimen with a paediatric low-dose of ICS as maintenance, consider increasing to a paediatric moderate-dose of ICS (either continuing a MART regimen, or changing to a ﬁxed-dose regimen of an ICS and a LABA with a short-acting beta2 agonist as reliever therapy). If asthma is still uncontrolled on a paediatric moderate- dose of ICS as maintenance with a LABA (either as a MART or a ﬁxed-dose regimen), consider seeking advice from an asthma specialist and the following options: . Increasing the ICS dose to a paediatric high-dose as maintenance (this should only be offered as part of a ﬁxed- dose regimen with a short-acting beta2 agonist as reliever therapy), or . A trial of an additional drug, such as modiﬁed-release theophylline p. 288. BTS/SIGN (2019) instead recommend that in children aged 5–12 years who are gaining some beneﬁt from the addition of a LABA or a LTRA but control remains inadequate, continue the LABA or LTRA and either increase the dose of the ICS to a low-dose (if not already on this dose), or add a LTRA or LABA (whichever is not being used). In children aged over 12 years, BTS/SIGN (2019) recommend continuing the LABA and either increasing the ICS dose to a medium-dose (if not already on this dose), or adding a LTRA. If there is no response to the LABA, consider discontinuing it and either increasing the dose of ICS to a low-dose (child aged 5–12 years) or medium-dose (child aged over 12 years) if not already on this dose, or adding a LTRA. BTS/SIGN (2019) recommend that all patients whose asthma is not adequately controlled on recommended initial add-on therapy or additional controller therapies, should be referred for specialist asthma care. h High-dose ICS and further add-on treatment (specialist therapies) g Under specialist care, BTS/SIGN (2019) recommend that if control remains inadequate on a low-dose (child aged 5–12 years) or medium-dose (child aged over 12 years) of ICS, plus a LABA or LTRA, the following interventions should be considered: . Increasing the ICS to a medium-dose (child aged 5–12 years) or high-dose (child aged over 12 years)—with ICS via a pressurised metered dose inhaler (pMDI) a spacer should be used, or . Adding a LTRA (if not already tried), or modiﬁed-release theophylline p. 288, or tiotropium p. 262 (in children over 12 years). If a trial of a further add-on treatment is ineffective, stop the drug (or in the case of increased dose of ICS, reduce to the original dose). h Continuous or frequent use of oral corticosteroids (specialist therapies) g Under specialist care, BTS/SIGN (2019) recommend adding a regular oral corticosteroid (prednisolone p. 716) at the lowest dose to provide adequate control in children with very severe asthma uncontrolled on a high-dose ICS, and who have also tried (or are still receiving) a LABA, LTRA, tiotropium p. 262 (child over 12 years), or modiﬁed-release theophylline p. 288. h For information on the general use and side effects of Respiratory system corticosteroids, see Corticosteroids, general use p. 707. For information on the cessation of oral corticosteroid treatment, see Treatment cessation for systemic corticosteroids (such as prednisolone). Monoclonal antibodies and immunosuppressants (specialist therapies) g Under specialist initiation, BTS/SIGN (2019) recommend that monoclonal antibodies such as omalizumab p. 282 (child over 6 years for severe persistent allergic asthma), and immunosuppressants such as methotrexate p. 963 [unlicensed] can be considered in children with severe asthma to achieve control and reduce the use of oral corticosteroids. h See National funding/access decisions for omalizumab p. 282. Child aged under 5 years Intermittent reliever therapy g A short-acting beta2 agonist (such as salbutamol p. 267) as reliever therapy should be offered to children aged under 5 years with suspected asthma. A short-acting beta2 agonist should be used for symptom relief alongside maintenance treatment. Children using more than one short-acting beta2 agonist inhaler device a month should have their asthma urgently assessed and action taken to improve poorly controlled asthma. h Regular preventer (maintenance) therapy NICE (2017) deﬁne inhaled corticosteroid (ICS) doses for children aged under 5 years as paediatric low or moderate. BTS/SIGN (2019) instead deﬁne ICS doses for children aged under 5 years as very low (refer to individual guidelines for ICS dosing information). g Consider an 8-week trial of a paediatric moderate- dose of ICS in children presenting with any of the following features: asthma-related symptoms three times a week or more, experiencing night-time awakening at least once a week, or suspected asthma that is uncontrolled with a short- acting beta2 agonist alone. After 8 weeks, stop ICS treatment and continue to monitor the child’s symptoms: . If symptoms did not resolve during the trial period, review whether an alternative diagnosis is likely; . If symptoms resolved then reoccurred within 4 weeks of stopping ICS treatment, restart the ICS at a paediatric low- dose as ﬁrst-line maintenance therapy; . If symptoms resolved but reoccurred beyond 4 weeks after stopping ICS treatment, repeat the 8-week trial of a paediatric moderate-dose of ICS. BTS/SIGN (2019) instead recommend starting a very low- dose of ICS as initial regular preventer therapy in children presenting with any one of the following features: using an inhaled short-acting beta2 agonist three times a week or more, symptomatic three times a week or more, or waking at night due to asthma symptoms at least once a week. In children unable to take an ICS, a leukotriene receptor antagonist (LRTA— such as montelukast p. 284) may be used as an alternative. BTS/SIGN (2019) recommend the prescribing of inhalers by brand. h Initial add-on therapy g If suspected asthma is uncontrolled in children aged under 5 years on a paediatric low-dose of ICS as maintenance therapy, consider a leukotriene receptor antagonist (LTRA—such as montelukast p. 284) in addition to the ICS. If suspected asthma is uncontrolled in children aged under 5 years on a paediatric low-dose of ICS and a LTRA as maintenance therapy, stop the LTRA and refer the child to an asthma specialist. h Decreasing treatment Respiratory system g Consider decreasing maintenance therapy when a patient’s asthma has been controlled with their current maintenance therapy for at least three months. When deciding which drug to decrease ﬁrst and at what rate, the severity of asthma, the side-effects of treatment, duration on current dose, the beneﬁcial effect achieved, and the patient’s preference should be considered. Patients should be regularly reviewed when decreasing treatment. Patients should be maintained at the lowest possible dose of ICS. Reductions should be considered every three months, decreasing the dose by approximately 25–50% each time. Reduce the dose slowly as patients deteriorate at different rates. Only consider stopping ICS treatment completely for people who are using a paediatric or adult low-dose ICS alone as maintenance therapy and are symptom-free. h Exercise-induced asthma g For most patients, exercise-induced asthma is an illustration of poorly controlled asthma and regular treatment including an ICS should therefore be reviewed. If exercise is a speciﬁc problem in patients already taking an ICS who are otherwise well controlled, consider adding either a LTRA, a long-acting beta2 agonist, sodium cromoglicate p. 285 or nedocromil sodium p. 285, or theophylline p. 288. An inhaled short-acting beta2 agonist used immediately before exercise is the drug of choice. h Pregnancy g Women with asthma should be closely monitored during pregnancy. It is particularly important that asthma is well controlled during pregnancy; when this is achieved there is little or no increased risk of adverse maternal or fetal complications. Women should be counselled about the importance and safety of taking their asthma medication during pregnancy to maintain good control. Women who smoke should be advised about the dangers to themselves and to their baby and be offered appropriate support to stop smoking. h For further information, see Smoking cessation p. 520. g Short-acting beta2 agonists, LABAs, oral and inhaled corticosteroids, sodium cromoglicate p. 285 and nedocromil sodium p. 285, and oral and intravenous theophylline p. 288 (with appropriate monitoring) can be used as normal during pregnancy. There is limited information on use of a LTRA during pregnancy, however, where indicated to achieve adequate control, they should not be withheld. h Advanced Pharmacy Services Patients with asthma may be eligible for the New Medicines Service / Medicines Use Review service provided by a community pharmacist. For further information, see Advanced Pharmacy Services in Medicines optimisation p. 18. Useful Resources Asthma: diagnosis, monitoring and chronic asthma management. National Institute for Health and Care Excellence. NICE guideline 80. November 2017. www.nice.org.uk/guidance/ng80 British guideline on the management of asthma. British Thoracic Society and Scottish Intercollegiate Guidelines Network. Full guidance - A national clinical guideline 158. July 2019. www.sign.ac.uk/assets/sign158.pdf Patient decision aid: Inhalers for asthma for use by people aged 17 years and over. National Institute for Health and Care Excellence. May 2019. www.nice.org.uk/about/what-we-do/our-programmes/nice- guidance/nice-guidelines/shared-decision-making Asthma, acute Description of condition Acute asthma is the progressive worsening of asthma symptoms, including breathlessness, wheeze, cough, and chest tightness. An acute exacerbation is marked by a reduction in baseline objective measures of pulmonary function, such as peak expiratory ﬂow rate and FEV1. Most asthma attacks severe enough to require hospitalisation develop relatively slowly over a period of six hours or more. In children, intermittent wheezing attacks are usually triggered by viral infections and response to asthma medication may be inconsistent. Low birth weight and/or prematurity may be risk factors for recurrent wheeze. Aims of treatment The aim of treatment is to relieve airﬂow obstruction and prevent future relapses. Early treatment is most advantageous. Levels of severity Adults g An acute exacerbation of asthma should be correctly differentiated from poor asthma control and it’s severity categorised in order to be appropriately treated. The categories are described as follows: h Moderate acute asthma . Increasing symptoms; . Peak ﬂow > 50-75% best or predicted; . No features of acute severe asthma. Severe acute asthma Any one of the following: . Peak ﬂow 33-50% best or predicted; . Respiratory rate 25/min; . Heart rate 110/min; . Inability to complete sentences in one breath. Life-threatening acute asthma Any one of the following, in a patient with severe asthma: . Peak ﬂow < 33% best or predicted; . Arterial oxygen saturation (SpO2) < 92%; . Partial arterial pressure of oxygen (PaO2) < 8 kPa; . Normal partial arterial pressure of carbon dioxide (PaCO2) (4.6–6.0 kPa); . Silent chest; . Cyanosis; . Poor respiratory effort; . Arrhythmia; . Exhaustion; . Altered conscious level; . Hypotension. Near-fatal acute asthma . Raised PaCO2 and/or the need for mechanical ventilation with raised inﬂation pressures. Children g An acute exacerbation of asthma should be correctly differentiated from poor asthma control and it’s severity categorised in order to be appropriately treated. The categories are described as follows: h Moderate acute asthma . Able to talk in sentences; . Arterial oxygen saturation (SpO2) 92%; . Peak ﬂow 50% best or predicted; . Heart rate 140/minute in children aged 1–5 years; heart rate 125/minute in children aged over 5 years; . Respiratory rate 40/minute in children aged 1–5 years; respiratory rate 30/minute in children aged over 5 years. Severe acute asthma . Can’t complete sentences in one breath or too breathless to talk or feed; . SpO2< 92%; . Peak ﬂow 33–50% best or predicted; . Heart rate > 140/minute in children aged 1–5 years; heart rate > 125/minute in children aged over 5 years; . Respiratory rate > 40/minute in children aged 1–5 years; respiratory rate > 30/minute in children aged over 5 years. Life-threatening acute asthma Any one of the following in a child with severe asthma: . SpO2< 92%; . Peak ﬂow < 33% best or predicted; . Silent chest; . Cyanosis; . Poor respiratory effort; . Hypotension; . Exhaustion; . Confusion. Management in adults g Patients with moderate acute asthma should be treated at home or in primary care according to response to treatment, while patients with severe or life-threatening acute asthma should start treatment as soon as possible and be referred to hospital immediately following initial assessment. Hospital referral may also be warranted in other cases, such as failure to respond to initial treatment, social circumstances, or concomitant disease. Supplementary oxygen should be given to all hypoxaemic patients with severe acute asthma to maintain an SpO2 level between 94–98%. Do not delay if pulse oximetry is unavailable. First-line treatment for acute asthma is a high-dose inhaled short-acting beta2 agonist (salbutamol p. 267 or terbutaline sulfate p. 269) given as soon as possible. If the response to an initial dose of short-acting beta2 agonist is poor, consider continuous nebulisation with an appropriate nebuliser. Intravenous beta2 agonists are reserved for those patients in whom inhaled therapy cannot be used reliably. In all cases of acute asthma, patients should be prescribed an adequate dose of oral prednisolone p. 716. Continue usual inhaled corticosteroid use during oral corticosteroid treatment. Parenteral hydrocortisone p. 713 or intramuscular methylprednisolone p. 715 are alternatives in patients who are unable to take oral prednisolone. h For information on the general use and side effects of corticosteroids, see Corticosteroids, general use p. 707. For information on the cessation of oral corticosteroid treatment, see Treatment cessation for systemic corticosteroids (such as prednisolone). g Nebulised ipratropium bromide p. 261 may be combined with a nebulised beta2 agonist in patients with severe or life-threatening acute asthma, or in those with a poor initial response to beta2 agonist therapy to provide greater bronchodilation. h There is some evidence that magnesium sulfate p. 1112 has bronchodilator effects. g A single intravenous dose of magnesium sulfate may be considered in patients with severe acute asthma (peak ﬂow < 50% best or predicted) who have not had a good initial response to inhaled bronchodilator therapy [unlicensed use]. h In an acute asthma attack, intravenous aminophylline p. 287 is not likely to produce any additional bronchodilation compared to standard therapy with inhaled bronchodilators and corticosteroids. However, in some patients with near-fatal or life-threatening acute asthma with a poor response to initial therapy, intravenous aminophylline may provide some beneﬁt. g Magnesium sulfate by intravenous infusion or aminophylline should only be used after consultation with senior medical staff. h Management in children aged 2 years and over g Children with severe or life-threatening acute asthma Respiratory system should start treatment as soon as possible and be referred to hospital immediately following initial assessment. Supplementary high ﬂow oxygen (via a tight-ﬁtting face mask or nasal cannula) should be given to all children with life-threatening acute asthma or SpO2< 94% to achieve normal saturations of 94–98%. First-line treatment for acute asthma is an inhaled short- acting beta2 agonist (salbutamol or terbutaline sulfate) given as soon as possible. The dose given should be individualised according to severity and adjusted based on response. Discontinue long-acting beta2 agonist use if a short-acting beta2 agonist is given more than 4 hourly. Seek medical attention if symptoms are not controlled with 10 puffs of salbutamol via a spacer; give additional bronchodilator doses whilst awaiting medical attention if symptoms are severe. In all cases of acute asthma, children should be prescribed an adequate dose of oral prednisolone. Treatment for up to 3 days is usually sufﬁcient, but the length of the course should be tailored to the number of days necessary to bring about recovery. Repeat the dose in children who vomit and consider the intravenous route in those who are unable to retain oral medication. It is considered good practice that inhaled corticosteroids are continued at their usual maintenance dose whilst receiving additional treatment for the attack, but they should not be used as a replacement for the oral corticosteroid. h For information on the general use and side effects of corticosteroids, see Corticosteroids, general use p. 707. For information on the cessation of oral corticosteroid treatment, see Treatment cessation for systemic corticosteroids (such as prednisolone p. 716). g Nebulised ipratropium bromide p. 261 can be combined with beta2 agonist treatment for children with a poor initial response to beta2 agonist therapy to provide greater bronchodilation. Consider adding magnesium sulfate [unlicensed use] p. 1112 to each nebulised salbutamol p. 267 and ipratropium bromide in the ﬁrst hour in children with a short duration of severe acute asthma symptoms presenting with an oxygen saturation less than 92%. Children with continuing severe acute asthma despite frequent nebulised beta2 agonists and ipratropium bromide plus oral corticosteroids, and those with life-threatening features, need urgent review by a specialist with a view to transfer to a high dependency unit or paediatric intensive care unit (PICU) to receive second-line intravenous therapies. In children who respond poorly to ﬁrst-line treatments, intravenous magnesium sulfate [unlicensed use] may be considered as ﬁrst-line intravenous treatment. In a severe asthma attack where the child has not responded to initial inhaled therapy, early addition of a single bolus dose of intravenous salbutamol may be an option. Continuous intravenous infusion of salbutamol, administered under specialist supervision with continuous ECG and electrolyte monitoring, should be considered in children with unreliable inhalation or severe refractory asthma. Aminophylline p. 287 may be considered in children with severe or life-threatening acute asthma unresponsive to maximal doses of bronchodilators and corticosteroids. h Children aged under 2 years g Acute asthma treatment for all children aged under 2 years should be given in the hospital setting. Treatment of children aged under 1 year should be under the direct guidance of a respiratory paediatrician. For moderate and severe acute asthma attacks, immediate treatment with oxygen via a tight-ﬁtting face mask or nasal prongs should be given to achieve normal SpO2 saturations of 94-98%. Trial an inhaled short-acting beta2 agonist and if response is poor, combine nebulised ipratropium bromide to each nebulised beta2 agonist dose. Consider oral Respiratory system prednisolone daily for up to 3 days, early in the management of severe asthma attacks. In children not responsive to ﬁrst-line treatments or have life-threatening features, discuss management with a senior paediatrician or the PICU team. h Follow up in all cases g Episodes of acute asthma may be a failure of preventative therapy, review is required to prevent further episodes. A careful history should be taken to establish the reason for the asthma attack. Inhaler technique should be checked and regular treatment should be reviewed. Patients should be given a written asthma action plan aimed at preventing relapse, optimising treatment, and preventing delay in seeking assistance in future attacks. It is essential that the patient’s GP practice is informed within 24 hours of discharge from the emergency department or hospital following an asthma attack, and the patient be reviewed by their GP within 2 working days. Patients who have had a near-fatal asthma attack should be kept under specialist supervision indeﬁnitely. A respiratory specialist should follow up all patients admitted with a severe asthma attack for at least one year after the admission. h Advanced Pharmacy Services Patients with asthma may be eligible for the New Medicines Service / Medicines Use Review service provided by a community pharmacist. For further information, see Advanced Pharmacy Services in Medicines optimisation p. 18. Useful Resources British guideline on the management of asthma. British Thoracic Society and Scottish Intercollegiate Guidelines Network. Full guidance - A national clinical guideline 158. July 2019. www.sign.ac.uk/assets/sign158.pdf Chronic obstructive pulmonary disease Description of condition Chronic obstructive pulmonary disease (COPD) is a common, largely preventable and treatable disease, characterised by persistent respiratory symptoms and airﬂow limitation that is usually progressive and not fully reversible. Airﬂow limitation is due to a combination of small airways disease (obstructive bronchiolitis) and parenchymal destruction (emphysema). Symptoms of COPD include dyspnoea, wheeze, chronic cough, and regular sputum production. The main risk factor for development and exacerbations of COPD is tobacco smoking. Other risk factors include environmental pollution and occupational exposures, genetic factors (such as hereditary alpha-1 antitrypsin deﬁciency), and poor lung growth during childhood. Complications of COPD include cor pulmonale, depression, anxiety, type 2 respiratory failure, and secondary polycythaemia. Asthma-COPD overlap syndrome (ACOS) is characterised by persistent airﬂow limitation that displays features of both asthma and COPD. Aims of treatment The primary aim of treatment is to reduce symptoms and exacerbations and improve quality of life. Management of stable COPD: For information on the management of patients during the COVID-19 pandemic, see COVID-19 p. 656. Non-drug treatment g Patients who are smokers should be encouraged to stop smoking and be offered help to do so. For further information, see Smoking cessation p. 520. All patients should receive care delivered by a multidisciplinary team. Pulmonary rehabilitation should be offered to appropriate patients, including those who view themselves as being functionally disabled by COPD. Pulmonary rehabilitation programmes should be tailored to the patient’s individual needs, and include physical training, disease education, and nutritional, psychological and behavioural intervention. Patients with excessive sputum production should be taught active cycle of breathing techniques, and how to use positive expiratory pressure devices by a physiotherapist. Refer patients with a BMI that is abnormal or changing over time for dietetic input, and be attentive to changes in weight in the elderly. Interventional procedures including surgery may be deemed appropriate following a respiratory review and input from the multidisciplinary team. h Vaccinations g All patients should be offered the pneumococcal vaccine and annual inﬂuenza vaccine p. 1392. h Inhaled treatment g The choice of inhaler device should be based on the patient’s preference and ability to use the inhaler. When prescribing an inhaler, patients should be trained on how to use the device and be able to demonstrate satisfactory inhaler technique, and continue to have their inhaler technique regularly assessed. Where appropriate a spacer can be provided. Nebulised treatment should be considered for patients with distressing or disabling breathlessness despite maximal use of inhalers, and continued if an improvement is seen in symptoms, ability to undertake activities of daily living, exercise capacity, or lung function. h For information on devices used in the management of COPD, see Respiratory system, drug delivery p. 249. Initial management for all patients g For initial empirical treatment, offer a short-acting bronchodilator as required to relieve breathlessness and exercise limitation. This can either be a short-acting beta2 agonist (SABA) or a short-acting muscarinic antagonist (SAMA). Before considering step-up treatment options, ensure that COPD is conﬁrmed spirometrically, relevant vaccinations are given, non-drug treatment options have been optimised including smoking cessation, and that a short-acting bronchodilator is being used. h Step-up treatment for patients without asthmatic features or features suggesting steroid responsiveness g In patients who continue to be breathless or have exacerbations, offer a long-acting beta2 agonist (LABA) and a long-acting muscarinic antagonist (LAMA). Discontinue SAMA treatment if a LAMA is given. Treatment with a SABA as required may be continued in all stages of COPD. In patients on a LAMA and LABA who have a severe exacerbation (requiring hospitalisation) or at least two moderate exacerbations (requiring systemic corticosteroids and/or antibacterial treatment) within a year, consider the addition of an inhaled corticosteroid (ICS)—triple therapy. If an ICS is given, review at least annually and document the reason for continuation. In patients on a LAMA and LABA whose day-to-day symptoms continue to adversely impact their quality of life, consider trialling the addition of an ICS for 3 months. If symptoms have improved, continue triple therapy and review at least annually. If there has been no improvement, step back down to a LAMA and LABA combination. h Step-up treatment for patients with asthmatic features or features suggesting steroid responsiveness g In patients who continue to be breathless or have exacerbations, consider treatment with a long-acting beta2 agonist (LABA) and an inhaled corticosteroid (ICS). If an ICS is given, review annually documenting the reason for continuation. In patients on a LABA and ICS who have a severe exacerbation (requiring hospitalisation) or at least two moderate exacerbations (requiring systemic corticosteroids and/or antibacterial treatment) within a year, or who continue to have day-to-day symptoms adversely impacting their quality of life, add a long-acting muscarinic antagonist (LAMA)—triple therapy. Discontinue SAMA treatment if a LAMA is given. Treatment with a SABA as required may be continued in all stages of COPD. h Prophylactic antibiotics g After considering if respiratory specialist input is required, consider azithromycin p. 566 [unlicensed] prophylaxis to reduce the risk of exacerbations in patients who are non-smokers, have had all other treatment options optimised, and who continue to either have prolonged or frequent (4 or more per year) exacerbations with sputum production, or exacerbations resulting in hospitalisation. Ensure sputum culture and sensitivity testing, a CT scan of the thorax (to rule out other lung pathologies), a baseline ECG (to rule out QT prolongation), and LFTs are performed before offering prophylaxis. Review treatment after the ﬁrst 3 months, then at least 6 monthly thereafter; only continue if beneﬁts outweigh risks. h Other treatments g Roﬂumilast p. 286 is recommended as add-on treatment to bronchodilator therapy in patients with severe COPD with chronic bronchitis (respiratory specialist initiation only), see National funding/access decisions for roﬂumilast. For guidance and the national funding access decision for roﬂumilast in Scotland, refer to the Scottish Medicines Consortium. Consider mucolytic treatment in patients with chronic cough productive of sputum; only continue if symptomatic improvement is seen. Antitussive treatment should not be used in the management of stable COPD. Modiﬁed-release theophylline p. 288 should only be used after a trial of short-acting and long-acting bronchodilators, or if the patient is unable to use inhaled treatment. Be alert to the presence of anxiety or depression in patients, and manage accordingly. h For information on oxygen therapy in COPD patients, see Oxygen p. 258. For guidance on the management of COPD patients with cor pulmonale and/or pulmonary hypertension, see NICE guideline: Chronic obstructive pulmonary disease in over 16s (see Useful resources). Management of exacerbations of COPD: For information on the management of patients during the COVID-19 pandemic, see COVID-19 p. 656. g Together with the patient, action plans should be created for those at risk of exacerbations. In patients who have had an exacerbation within the last year, a short course of antibacterials (non-macrolide if on prophylactic azithromycin) and oral corticosteroids should be kept at home. Patients should understand and be conﬁdent with when and how to take these medicines, and to report having taken them to their healthcare professional. Patients may continue prophylactic azithromycin during an acute exacerbation. Action plans may also include information on adjusting the short-acting bronchodilator dose, and a cognitive behavioural plan to manage symptoms of anxiety and associated breathlessness. h For guidance on assessing the need for hospital referral, see NICE guideline: Chronic obstructive pulmonary disease in over 16s (see Useful resources). For guidance on antibacterial treatment in acute Respiratory system exacerbations of COPD, see Chronic obstructive pulmonary disease, acute exacerbations in Respiratory system infections, antibacterial therapy p. 538. Non-drug treatment: g Where appropriate consider physiotherapy using positive expiratory pressure devices to help with sputum clearance. h Drug treatment g Give short-acting inhaled bronchodilators, usually at higher doses than the patient’s maintenance treatment through a nebuliser or hand-held device to manage breathlessness. The choice should be dependant on the dose required, the patient’s ability to use the device, and resources available to supervise administration. Withhold LAMA treatment if a SAMA is given. In the absence of signiﬁcant contra-indications in patients that present to hospital with an exacerbation, use a short course of prednisolone p. 716 along with other therapies. Consider a short course for patients in the community experiencing an exacerbation with a signiﬁcant increase in breathlessness that interferes with daily activities. Consider osteoporosis prophylaxis for patients who require frequent courses of oral corticosteroids. Long-term oral corticosteroid treatment is not usually recommended, however in some patients this may need to be continued when withdrawal following an exacerbation is not possible; the lowest dose possible should be used. Monitor patients for osteoporosis and give them appropriate prophylaxis. Start prophylaxis without monitoring for osteoporosis in patients aged over 65 years. h For information on the general use and side effects of corticosteroids, see Corticosteroids, general use p. 707. For information on the cessation of oral corticosteroid treatment, see Treatment cessation for systemic corticosteroids (such as prednisolone). g Aminophylline p. 287 should only be used as add-on treatment when there is an inadequate response to nebulised bronchodilators; ensure therapeutic drug monitoring is performed and that previous oral theophylline use is considered to avoid toxicity. If necessary, oxygen should be given to ensure oxygen saturation of arterial blood levels are kept within the target range for the patient. For further information, see Oxygen p. 258. For patients with persistant hypercapnic ventilatory failure, use non-invasive ventilation (NIV) if patients experience exacerbations despite the optimisation of medical treatment. If deemed necessary, invasive ventilation for COPD exacerbations should be given in an intensive care unit. Doxapram should only be given when NIV is inappropriate or unavailable in the clinical setting. h Advanced Pharmacy Services Patients with chronic obstructive pulmonary disease may be eligible for the New Medicines Service / Medicines Use Review service provided by a community pharmacist. For further information, see Advanced Pharmacy Services in Medicines optimisation p. 18. Useful Resources Chronic obstructive pulmonary disease in over 16s: diagnosis and management. National Institute for Health and Care Excellence. NICE guideline 115; December 2018, updated July 2019. www.nice.org.uk/guidance/ng115 Chronic obstructive pulmonary disease (acute exacerbation): antimicrobial prescribing. National Institute for Health and Care Excellence. NICE guideline 114; December 2018. www.nice.org.uk/guidance/ng114 Respiratory system Oxygen Overview Oxygen should be regarded as a drug. It is prescribed for hypoxaemic patients to increase alveolar oxygen tension and decrease the work of breathing. The concentration of oxygen required depends on the condition being treated; the administration of an inappropriate concentration of oxygen can have serious or even fatal consequences. Oxygen is probably the most common drug used in medical emergencies. It should be prescribed initially to achieve a normal or near–normal oxygen saturation; in most acutely ill patients with a normal or low arterial carbon dioxide (Pa CO2), oxygen saturation should be 94–98% oxygen saturation. However, in some clinical situations such as cardiac arrest and carbon monoxide poisoning it is more appropriate to aim for the highest possible oxygen saturation until the patient is stable. A lower target of 88–92% oxygen saturation is indicated for patients at risk of hypercapnic respiratory failure. High concentration oxygen therapy is safe in uncomplicated cases of conditions such as pneumonia, pulmonary thromboembolism, pulmonary ﬁbrosis, shock, severe trauma, sepsis, or anaphylaxis. In such conditions low arterial oxygen (Pa O2) is usually associated with low or normal arterial carbon dioxide (Pa CO2), and therefore there is little risk of hypoventilation and carbon dioxide retention. In acute severe asthma, the arterial carbon dioxide (Pa CO2) is usually subnormal but as asthma deteriorates it may rise steeply (particularly in children). These patients usually require high concentrations of oxygen and if the arterial carbon dioxide (Pa CO2) remains high despite other treatment, intermittent positive-pressure ventilation needs to be considered urgently. Low concentration oxygen therapy (controlled oxygen therapy) is reserved for patients at risk of hypercapnic respiratory failure, which is more likely in those with: . chronic obstructive pulmonary disease (COPD); . advanced cystic ﬁbrosis; . severe non-cystic ﬁbrosis bronchiectasis; . severe kyphoscoliosis or severe ankylosing spondylitis; . severe lung scarring caused by tuberculosis; . musculoskeletal disorders with respiratory weakness, especially if on home ventilation; . an overdose of opioids, benzodiazepines, or other drugs causing respiratory depression. g Until blood gases can be measured, initial oxygen should be given using a controlled concentration of 24% or 28%, titrated towards a target oxygen saturation of 88–92% or the level speciﬁed on the patient’s oxygen alert card if available. h The aim is to provide the patient with enough oxygen to achieve an acceptable arterial oxygen tension without worsening carbon dioxide retention and respiratory acidosis. g Patients with COPD and other at-risk conditions who have had an episode of hypercapnic respiratory failure, should be given a 24% or 28% Venturi mask and an oxygen alert card endorsed with the oxygen saturations required during previous exacerbations. Patients and their carers should be instructed to show the card to emergency healthcare providers in the event of an exacerbation. h The oxygen alert card template is available at www.brit- thoracic.org.uk. Domiciliary oxygen Oxygen should only be prescribed for use in the home after careful evaluation in hospital by respiratory experts. Patients should be advised of the risks of continuing to smoke when receiving oxygen therapy, including the risk of ﬁre. Smoking cessation therapy p. 520 should be recommended before home oxygen prescription. g In patients with COPD, it should only be provided if the patient has stopped smoking. h Air travel Some patients with arterial hypoxaemia require supplementary oxygen for air travel. The patient’s requirement should be discussed with the airline before travel. Long-term oxygen therapy Long-term administration of oxygen (usually at least 15 hours daily) improves survival in COPD patients with more severe hypoxaemia. g The need for oxygen should be assessed in COPD patients with an FEV1 less than 30% predicted (consider assessment if FEV1 is 30-49%), cyanosis, polycythaemia, peripheral oedema, raised JVP, and when oxygen saturation levels are 92% or less breathing air. h Assessment for long-term oxygen therapy requires measurement of arterial blood gas tensions. Measurements should be taken on 2 occasions at least 3 weeks apart to demonstrate clinical stability. Long-term oxygen therapy should be considered for patients with: . g COPD with Pa O2<7.3 kPa when stable and who do not smoke (minimum of 15 hours per day); . COPD with Pa O2 7.3–8 kPa when stable and do not smoke, and also have either secondary polycythaemia, peripheral oedema, or evidence of pulmonary hypertension (minimum of 15 hours per day); h . severe chronic asthma with Pa O2<7.3 kPa or persistent disabling breathlessness; . interstitial lung disease with Pa O2<8 kPa and in patients with Pa O2>8 kPa with disabling dyspnoea; . cystic ﬁbrosis when Pa O2<7.3 kPa or if Pa O2 7.3–8 kPa in the presence of secondary polycythaemia, nocturnal hypoxaemia, pulmonary hypertension, or peripheral oedema; . pulmonary hypertension, without parenchymal lung involvement when Pa O2<8 kPa; . neuromuscular or skeletal disorders, after specialist assessment; . obstructive sleep apnoea despite continuous positive airways pressure therapy, after specialist assessment; . pulmonary malignancy or other terminal disease with disabling dyspnoea; . heart failure with daytime Pa O2<7.3 kPa when breathing air or with nocturnal hypoxaemia; . paediatric respiratory disease, after specialist assessment. Increased respiratory depression is seldom a problem in patients with stable respiratory failure treated with low concentrations of oxygen although it may occur during exacerbations; patients and relatives should be warned to call for medical help if drowsiness or confusion occur. g A risk assessment should be carried out for all COPD patients being considered for long-term oxygen therapy and if treatment is given, should be reviewed at least annually. Offer smoking cessation advice, treatment and specialist referral for people who smoke or smokers living with the patient with COPD. Do not offer long-term oxygen therapy to patients who continue to smoke despite being offered smoking cessation interventions. h Short-burst oxygen therapy Oxygen is occasionally prescribed for short-burst (intermittent) use for episodes of breathlessness not relieved by other treatment in patients with interstitial lung disease, heart failure, and in palliative care. It is important, however, that the patient does not rely on oxygen instead of obtaining medical help or taking more speciﬁc treatment. Short-burst oxygen therapy can be used to improve exercise capacity and recovery; it should only be continued if there is proven improvement in breathlessness or exercise tolerance. g It is not recommended for COPD patients who have mild or no hypoxaemia at rest. h Ambulatory oxygen therapy Ambulatory oxygen is prescribed for patients on long-term oxygen therapy who need to be away from home on a regular basis. Patients who are not on long-term oxygen therapy can be considered for ambulatory oxygen therapy if there is evidence of exercise-induced oxygen desaturation and of improvement in blood oxygen saturation and exercise capacity with oxygen. Ambulatory oxygen therapy is not recommended for patients with heart failure, COPD with mild or no hypoxaemia at rest, or those who smoke. Oxygen therapy equipment Under the NHS oxygen may be supplied as oxygen cylinders. Oxygen ﬂow can be adjusted as the cylinders are equipped with an oxygen ﬂow meter with ‘medium’ (2 litres/minute) and ‘high’ (4 litres/minute) settings. Oxygen delivered from a cylinder should be passed through a humidiﬁer if used for long periods. Oxygen concentrators are more economical for patients who require oxygen for long periods, and in England and Wales can be ordered on the NHS on a regional tendering basis. A concentrator is recommended for a patient who requires oxygen for more than 8 hours a day (or 21 cylinders per month). Exceptionally, if a higher concentration of oxygen is required the output of 2 oxygen concentrators can be combined using a ‘Y’ connection. A nasal cannula is usually preferred for long-term oxygen therapy from an oxygen concentrator. It can, however, produce dermatitis and mucosal drying in sensitive individuals. Giving oxygen by nasal cannula allows the patient to talk, eat, and drink, but the concentration of oxygen is not controlled; this may not be appropriate for acute respiratory failure. When oxygen is given through a nasal cannula at a rate of 1–2 litres/minute the inspiratory oxygen concentration is usually low, but it varies with ventilation and can be high if the patient is underventilating. Arrangements for supplying oxygen The following oxygen services may be ordered in England and Wales: . emergency oxygen; . short-burst (intermittent) oxygen therapy; . long-term oxygen therapy; . ambulatory oxygen. The type of oxygen service (or combination of services) should be ordered on a Home Oxygen Order Form (HOOF); the amount of oxygen required (hours per day) and ﬂow rate should be speciﬁed. The clinician will determine the appropriate equipment to be provided. Special needs or preferences should be speciﬁed on the HOOF. The clinician should obtain the patient or carers consent, to pass on the patient’s details to the supplier, the ﬁre brigade, and other relevant organisations. The supplier will contact the patient to make arrangements for delivery, installation, and maintenance of the equipment. The supplier will also train the patient or carer to use the equipment. The clinician should send the HOOF to the supplier who will continue to provide the service until a revised HOOF is received, or until notiﬁed that the patient no longer requires the home oxygen service. . East of England, North East: BOC Medical: Tel: 0800 136 603 Fax: 0800 169 9989 . South West: Air Liquide: Tel: 0808 202 2229 Fax: 0191 497 . London, East Midlands, North West: Air Liquide: Tel: 0500 823 773 Fax: 0800 781 4610 . Yorkshire and Humberside, West Midlands, Wales: Air Products: Tel: 0800 373 580 Fax: 0800 214 709 Respiratory system . South East Coast, South Central: Dolby Vivisol: Tel: 08443 814 402 Fax: 0800 781 4610 In Scotland refer the patient for assessment by a respiratory consultant. If the need for a concentrator is conﬁrmed the consultant will arrange for the provision of a concentrator through the Common Services Agency. Prescribers should complete a Scottish Home Oxygen Order Form (SHOOF) and email it to Health Facilities Scotland. Health Facilities Scotland will then liaise with their contractor to arrange the supply of oxygen. Further information can be obtained at: www.dolbyvivisol.com/services/healthcare-professionals/. In Northern Ireland oxygen concentrators and cylinders should be prescribed on form HS21; oxygen concentrators are supplied by a local contractor. Prescriptions for oxygen cylinders and accessories can be dispensed by pharmacists contracted to provide domiciliary oxygen services. Croup Management Mild croup is largely self-limiting, but treatment with a single dose of a corticosteroid (e.g. dexamethasone p. 712) by mouth may be of beneﬁt. More severe croup (or mild croup that might cause complications) calls for hospital admission; a single dose of a corticosteroid (e.g. dexamethasone or prednisolone p. 716 by mouth) should be administered before transfer to hospital. In hospital, dexamethasone (by mouth or by injection) or budesonide p. 273 (by nebulisation) will often reduce symptoms; the dose may need to be repeated after 12 hours if necessary. For severe croup not effectively controlled with corticosteroid treatment, nebulised adrenaline/epinephrine p. 236 solution 1 in 1000 (1 mg/mL) should be given with close clinical monitoring; the effects of nebulised adrenaline/epinephrine last 2–3 hours and the child needs to be monitored carefully for recurrence of the obstruction. Other drugs used for Airways disease, obstructive Dupilumab, p. 1323 ANTIMUSCARINICS Antimuscarinics (inhaled) f

PDF pages 270, 271, 272, 273, 274, 275, 276, 277, 278, 279, 280, 281

Medicinal Forms

PDF pages 270, 271, 272, 273, 274, 275, 276, 277, 278, 279, 280, 281

Sodium tetradecyl sulfate

Overview

Indications And Dose

Contra Indications

Cautions

Safety

Side Effects

Pregnancy

Breast Feeding

Dose and formulations

Medicinal Forms

Dose text by age group

Sodium tetradecyl sulfate

Overview

Indications And Dose

Contra Indications

Cautions

Safety

Side Effects

Pregnancy

Breast Feeding

Dose and formulations

Medicinal Forms

Dose text by age group