Salbutamol nebulised

A 63-year-old woman, 67 kg, is admitted to hospital with chest pain, shortness of breath and sweating. She is seen in casualty and treated using a salbutamol nebuliser. She looks obese. She has been a life-long smoker who stopped one... 

The hyperkalaemia is the most life-threatening symptom at present. Initially, the patient could be given salbutamol nebulisers, since salbutamol acts via... 

Salbutamol is a selective (32 agonist that may be administered by inhalation from either a pressurised aerosol delivering 100 pg per puff (standard dose 1-2 puffs) or a powder inhaler (metered dose 500 pg). The duration of action is 4-6 hours. In patients unable to use a pressurised aerosol, salbutamol-containing solution may be nebulised in a stream of oxygen using a specially designed face mask. Similarly, salbutamol-containing solution can be nebulised and introduced into the inspiratory limb of a mechanical ventilation system. 

Salbutamol may be administered parenterally as an intravenous infusion at 3-20 pg min-1 with the dose being titrated to therapeutic effect. Side effects notably tachycardia are more common with parenteral or nebulised formulations. The drug may also be administered by the subcutaneous or intramuscular routes. Salbutamol is conjugated in the liver and excreted both in the urine as unchanged drug and metabolites, and also in the faeces. 

The patient was discharged from hospital three weeks ago with antibiotics. There was some improvement, but he is still very short of breath at rest. Five days ago, with worsening shortness of breath over the previous week, the patient took clarithromycin 500 mg b.d. Four days ago he took prednisolone 30 mg daily but has now stopped, with no improvement. He is using nebulisers 7 times daily (salbutamol + ipratropium). Because he was no better today, his daughter called an ambulance. 

Salbutamol is available as tablets, inhalers, nebuliser solution and intravenous injection. In the management of asthma at step 1 and 2 the inhaled formulation is the best option since it targets the drug and minimises side-effects. Oral tablets of salbutamol are rarely used and there is limited evidence of their effectiveness. 

Nebulised and intravenous salbutamol is required for more severe and acute status asthmaticus. 

Patient s COPD seems to be controlled on combination of inhalers and nebuliser solution. He would use salbutamol and ipratropium solution 2-3 times a day, but when his COPD got worse, he would increase to 4-6 times daily. 

A small number of cases of acute angle-closure glaucoma have been reported in patients treated with a combination of nebulised salbutamol and ipratropium bromide, caused possibly by local absorption of mist containing both products. A combination of nebulised salbutamol with nebulised anticholinergics should therefore be used cautiously. Patients should receive adequate instruction in correct administration and be warned not to let the solution or mist enter the eyes. Use of a mouthpiece rather than a mask for administration would reduce the risk associated with this. 

A 3-year-old boy comes into A E with a severe asthma attack. This is his third in the last three months. He is started on nebulised salbutamol, intravenous aminophylline and oral prednisolone. The presenting symptoms include ... 

Newnham, D. M., and Lipworth, B. J. (1994), Nebuliser performance, pharmacokinetics, airways and systemic effects of salbutamol given via a novel nebuliser delivery system ( ventstream ), Thorax, 49,762-770. 

Lipworth, B. J., Sims, E. J., Taylor, K., Cockburn, W., and Fishman, R. (2005), Dose-response to salbutamol via a novel palm sized nebuliser (aerodose inhaler), conventional nebuliser (pari LC plus) and metered dose inhaler (ventolin evohaler) in moderate to severe asthmatics, Br. J. Clin. Pharmacol, 59, 5-13. 

Give i.v. either salbutamol 250 microgram over 10 minutes (as nebulised salbutamol may not be reaching the distal airways) or aminophylUne... 

Connett G, Lenney W. Prolonged hypoxaemia after nebulised salbutamol. Thorax 1993 48(5) 574-5. 

The manufacturer notes that atomoxetine 60 mg twice daily for 5 days potentiated the increase in heart rate and blood pressure caused by an infusion of salbutamol 600 micrograms over 2 hours. Because of this, they recommend caution when atomoxetine is used in patients receiving intravenous or oral salbutamol or other beta2 agonists (for a list, see Table 33. r, (p.ll59)). The UK manufacturer also extends this precaution to high-dose nebulised salbutamol. ... 

Hypokaiaemia The hypokalaemic effects of betaj agonists may be increased by eortieosteroids. Twenty-four healthy subjects had a fall in their serum potassium levels when they were given either salbutamol (albuterol) 5 mg or fenoterol 5 mg by nebuliser over 30 minutes. The fall in potassium levels was inereased after they took prednisone 30 mg daily for a week. The greatest fall (from 3.75 to 2.78mmol/L) was found 90 minutes after fenoterol and prednisone were taken. The ECG effects observed included ectopic beats and transient T wave inversion, but no significant ECG disturbances were noted in these healthy subjects. ... 

Acute angle-closure glaucoma developed rapidly in eight patients given nebulised ipratropium and salbutamol. Increased intra-ocular pressure has been reported in others, including one patient using an ipratropium metered-dose inhaler with nebulised salbutamol. 

ShahP,DhurjonL, Metcalfe T, Gibson JM. Acute angle closure glaucoma associated with nebulised ipratropium bromide and salbutamol. BMJ (1992) 304, 40-1. 

Packe GE, Cayton RM, Mashoudi N. Nebulised ipratropium bromide and salbutamol causing closed-angle glaucoma. Lancet 9%A) ii, 691. 

Prendiville A, Green S, Silverman M. Paradoxical response to nebulised salbutamol in wheezy infants, assessed by partial expiratory flow-volume curves. Thorax 1987 42 86-91. 

Robertson CF, Smith F, Beck R, Levison H. Response to frequent low doses of nebulised salbutamol in acute asthma. J Pediatr 1985 106 672-674. 

Zainudin BMZ, Biddiscombe M, Tolfree SEJ, Short M, Spiro SG. Deposition patterns of salbutamol inhaled from a pressurised metered dose inhaler, as a dry powder, and as a nebulised solution. Thorax 1990 45 469-473. 

Most product information leaflets for nebulised medicine formulations discourage mixing of marketed formulations but in practice different formulations are frequently mixed to increase patient comfort. Particularly CF patients tend to combine medicines in order to save time as well as to overcome adverse effects (e.g. bronchoconstriction) of one active substance (antibiotic) by another (salbutamol). They also tend to refill their nebuliser with a new medicine without emptying and cleaning the nebuliser between the administrations. Relatively little has been reported in the literature about the compatibility of medicine mixtures, however, and interactions may be expected with respect to chemical and physical stability, droplet size distribution of the aerosol, nebuliser output rate and therapeutic effect. From a survey of studies on chemical stability, it is known that particularly domase alpha (Pulmozyme ) is incompatible with many other nebulised medicine formulations due to inactivation of the protein [63]. Additives, like stabilisers that work well in some medicine formulations, may be incompatible with other preparations and induce cloudiness... 

Nervous System A case of anisocoria has been affribufed to iprafropium [46 ]. A 7-year-old child with severe refractory asthma was admitted in the pediatric intensive care xmit. The patient was started on noninvasive ventilation (NIV) and received nebulised salbutamol and ipratropium. Eighteen hours after the admission anisocoria was noted, which gradually subsided once ipratropium was stopped. Nebulised ipratropium leaking from the NIV may be transferred to the conjunctiva, causing the anticholinergic side effects. 

C. Grainge, R. F. R. Brown, B. Jugg, A. Smith, T. Mann, J. Jenner, P. Rice and D. A. Parkhouse, Early treatment with nebulised salbutamol worsens physiological measures and does not improve survival following phosgene induced acute lung injury,/. R. Army Med. Corps, 2009, 155, 105-109. 

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