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Resuscitation, 15 (1987) 135-139 Elsevier Scientific Publishers Ireland Ltd.
EMERGENCY AEROSOL
D.J. STEEDMAN Department 9YW (U.K.)
ENDOTRACHEAL
DRUG
ADMINISTRATION
USING
and C.E. ROBERTSON
of Accident
and Emergency
(Received September 22nd, 1986) (Revision received November llth, (Accepted November 12th, 1986)
Medicine,
Royal Infirmary,
Edinburgh,
EH3
1986)
SUMMARY
Drug administration via the endotracheal route has previously involved direct installation in bolus form. However this necessitates an interruption in ventilation and, for the administration of therapeutic agents to the lungs, may result in failure of delivery to the appropriate sites. Aerosols have advantages over other routes of administration since the drug is delivered directly to its required site of action. Treatment with nebulised beta-2 agonists is the initial treatment of choice in acute severe asthma and a small number of such patients require immediate intubation and ventilation. We describe a technique for aerosol delivery using a nebuliser which can be used in intubated patients during manual intermittent positive pressure ventilation using a bag-valve resuscitator,
Key words: Endotracheal drug administration - Nebuliser - Beta-2 agonists - Intermittent positive pressure ventilation - Bag-valve resuscitator
INTRODUCTION
In the past, clinical experience of administering drugs via the endotracheal tube has involved direct instillation in bolus form [l]. However, for the administration of therapeutic agents to the lungs, aerosols have advantages over other routes since the drug is delivered directly to its required site of action reducing the incidence of systemic side effects [2]. We report on the use of a nebuliser (Inspiron 003249) in the emergency setting, which can be used in intubated patients to provide a satisfactory aerosol during manual 0300-9572/87/$03.50 0 Elaevier Scientific Printed and Pu bliahed in Ireland
Publishers Ireland Ltd.
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Fig. 1. The nebuliser (Inspiron 003249) is available from Bard Ltd., Pennywell Industrial Estate, Sunderland, SR4 9EW Tel 0783 343131.
intermittent positive pressure ventilation (IPPV) using a bag-valve resuscitator and therefore improve delivery to receptor sites within the lungs. METHOD
The nebuliser unit (Fig. 1) comprises a clear plastic reservoir with a screw attachment to the lid which incorporates standard connections for ventilatory circuit tubing. The nebuliser drive line tubing from an oxygen cylinder is connected to the nebuliser stem on top of the lid. The medication can be instilled in the reservoir prior to connection and further doses can be added via the side port without disconnecting the apparatus while it is in use. The aerosol produced at the end of the endotracheal tube is demonstrated in Fig. 2. The use of the nebuliser is exemplified in the following case.
Fig. 2. Aerosol produced at the end of the endotracheal
tube.
Case Report A 23-year-old woman who had had asthma since childhood presented in a moribund state to the Accident and Emergency Department with a history of increasing dyspnoea and wheeze over the previous half hour. Prior to admission she had become apnoeic and external cardiac massage with mouth-to-mouth respiration was begun. On admission she was cyanotic, apnoeic and initially had no palpable pulse. She was intubated and ventilated with 100% oxygen using a bag-valve resuscitator. Lung inflation pressures were >80 cm water. Following intubation, the electrocardiogram showed a sinus tachycardia. Aminophylline (250 mg) and hydrocortisone (500 mg) were given intravenously. Five minutes after presentation, arterial blood gases revealed H’ 145 nmol/l, PCOz 11.2 kPa, HCO,- 14 mmol/l and PO, 16.6 kPa. Chest X-ray showed hyperinflated lung fields. There was no pneumothorax. Inflation pressures remained high and nebulised Salbutamol was administered via the endotracheal tube. Within 10 min of administration, the inflation pressure had fallen to 20-30 cm water with a striking improvement in air entry on auscultation of the chest. The patient’s mental status improved and she was extubated after 15 min at which time blood gas results were H’ 79 nmol/l, PCO~ 5.6 kPa, HCOB13 mmol/l and PO, 11.8 kPa. She made a complete recovery with no evi-
Fig. 3. Nebuliser in use in a patient with smoke inhalation.
dence
of hypoxic brain damage and was discharged from hospital after 3
days. DISCUSSION
Treatment with nebulised beta-2 agonists is the initial treatment of choice in acute severe asthma [ 31 but this route relies on the patient’s ability to inhale satisfactorily. However, a small number of such patients require immediate intubation and ventilation [4]. While beta-2 agonists may be given parenterally to such patients, the doses required to achieve a therapeutic result are much higher and the adverse effects correspondingly greater [ 51. Bolus administration of the drug via the endotracheal tube necessitates an interruption in ventilation, and may fail to deliver the drug to the appropriate sites. The use of a polyethylene catheter inserted via the endotracheal tube may result in a more distal delivery, but may induce or aggravate bronchospasm by a direct action. Aerosol delivery using’ the technique described is simple and occurs without interruption of positive pressure ventilation. Since the therapeutic effect of drugs such as Salbutamol will depend not only upon the amount of aerosol reaching the lungs [ 61, but also upon its airway distribution [ 71 we would suggest that this route is indicated in similar cases.
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To date we have employed the technique in several patients suffering from bronchospasm due to acute severe asthma or smoke inhalation (Fig. 3) with good effect. The ease of use and efficacy suggests that the administration of other drugs in varied clinical situations may be appropriate. REFERENCES MI. Greenberg, The use of endotracheal medication in cardiac emergencies. Resuscitation, 12 (3) (1984) 155-165. S.P. Newman and S.W. Clarke, Therapeutic aerosols 1 - physical and practical considerations, Thorax, 38 (1983) 881-886. Editorial, Acute Asthma, Lancet, i (1976) 131-132. C.H. Scoggin, S.A. Sahn and T.L. Petty, Status Asthmaticus: A nine year experience, J. Am. Med. Assoc., 238 (1977) 1158-1162. P. Bloomfleld, J. Carmichael, G.R. Petrie, N.P. Jewel1 and G.K. Crompton, Comparison of Salbutamol given intravenously and by intermittent positive pressure breathing in life threatening asthma, Br. Med. J., i (1979) 845-850. E.W. Blackwell, R.H. Briant, M.E. Connolly, D.S. Davies and CT. Dollery, Metabolism of Isoprenaline after aerosol and direct intrabronchial administration in man and dog, Br. J. Pharmacol., 50 (1974) 587-591. S. Godfrey, E. Zeidifard, K. Brown and J.H. Bell, The possible site of action of sodium cromoglycate assessed by exercise challenge, Clin. Sci. Mol. Med., 46 (1974) 265-272.