Br. J. Dis.
Chest ( 1984)
78,26 1
Short Communication-
PULMONARY FUNCTION CHANGES AFTER BRONCHOALVEOLAR LAVAGE IN ASTHMATIC PATIENTS PATRICIA *Dept.
Medicina
ANCIC*,
PATRICIA
DfAZt:
AND F. GALLEGUILLOS:
Oriente U. de Chile, tDept. Medicina Experimental and : Clinica Miguel de Seruet, Santiago, Chile
SW U. de Chile,
Summary
Pulmonary function changes were studied following bronchoalveolar lavage (BAL) in a group of mild to moderate asthmatic patients and in control subjects. After BAL significant decreases in FEV, and FVC which were not inhibited by atropine and a consistent decline in Pao2 were seen in both groups. The magnitude of changes in these asthmatics was similar to that in control subjects. Introduction Bronchoalveolar lavage (BAL) has become a widely employed technique in the research of a variety of pulmonary disorders. In asthma, BAL has been used to study pathological mechanisms involved (Godard et al. 1981). Since the asthmatic population may be at higher risk we attempted to determine the changes in pulmonary function induced by BAL in a group of asthmatic patients as compared to changes observed in healthy subjects. Material
and Methods
Six atopic patients with mild to moderate asthma, two females and four males aged 15-43 (mean 24) years, and seven non-smoking healthy volunteers, six females and one male aged 15-20 (mean 16) years, were studied before and after bronchoalveolar lavage. All patients were currently treated with aminophylline slow release as a single dose (375 mg) in the evening and inhaled salbutamol as required. Bronchodilators were withdrawn for at least 14 hours before the test. Their resting FEVi was above 90% of predicted values. The control subjects had no history of allergy or respiratory pathology and had a negative skin prick test. All ofthem gave informed consent. Premeditation consisted of atropine 1 mg and diazepam 5 mg, 30-40 minutes before the procedure. The bronchoscope was passed transnasally after lignocaine (3 ml at 4%) had been instilled on to the pharyx and larynx. The scope was wedged into the anterior segment of the right upper lobe or middle lobe. Four 50 ml aliquots of sterile 0.9% sodium chloride solution at room temperature were injected and immediately aspirated. Forced vital capacity (FVC) and forced expiratory volume in one second (FEV,) were determined in a Collins dry spirometer. These measurements were made at rest, 30 minutes after atropine, just after topical lignocaine (before the bronchoscope was introduced) and immediately after lavage. Arterial Reprint requests: Patricia Ancid, Clinica
Miguel
de Servet, Casilla
16237, Santiago
&, Chile.
Patricia AnciC, Patricia Diaz and F. Galleguillos
262
blood samples were taken at the start of the study and during the last aspiration gas analysis was performed on a Radiometer blood gas analyser (BMS 3MK2). Student’s paired test was used in the statistical analysis.
of lavage fluid. Blood
Results FVC, FEVi, Pao2, Pacon, D(A-a)02 in asthmatics and control subjects under different conditions are shown in Table I. After BAL there was a statistically significant decrease in FEVi and FVC in the asthmatic patients and control subjects. The fall was of the same magnitude in both groups. No significant changes in these values were observed after atropine or lignocaine. Table I. Pulmonary
FVC FEV,
Pa02 PacoY D(A-a)02
function
changes after BAL in asthmatic
patients
and control subjects
Basal % of predicted values
A tropine Lignocaine % change from basal values
Lavage
Mean ? 1 SEM
Mean t 1 SEM
Mean k 1 SEM
Mean ? 1 SEM
Asthmatics Controls Asthmatics Controls
109.9 98.7 101.1 99.2
+ +
-3.1 Ib3.7 - 1.0+ 1.3 - 0.8 + 3.4 + 8.7 I!I 2.5
- 13.3 + 2.8* - 15.8+2.5t - 11.823.1: -11.0*2.9*
Asthmatics Controls Asthmatics Controls Asthmatics Controls
mmHg (mean * 1 SEM) 77.5 zb 2.6 82.9 2 2.9 35.1 ? 1.O 32.1 & 1.2 18.6? 1.8 14.5k2.1
-
mmHg (mean * 1 SEM) 57.3 k 3.4: 61.0*3.4? 34.2 k 1.2 32.3 k 1.6 39.7 f 2.8* 38.5 f 2.65
f + ? +
3.8 3.8 3.8 4.8
*P
1.9f2.5 1.6f 1.3 0.8 If: 2.8 1.4f 3.3
-
4 P
All subjects studied showed a statistically without change in the Pacop or pH values.
significant
fall in Pao2 after lavage
Discussion The fall in spirometric values were less than those reported by Godard et al. ( 1981) in a group of asthmatics. Alveolar filling and bronchoconstriction induced by the lavage may be the cause of the fall, as changes in pulmonary mechanics secondary to fibreoptic bronchoscopy can be inhibited by premeditation with atropine (Neuhaus et al. 1978). BAL may increase or coincide with the fall in Paop produced by the fibreoptic bronchoscopy itself (Albertini et al. 1974). Alveolar filling and removal and/or interference with surfactant will produce mismatching of ventilation/
Pulmonary Function Changes after Bronchoalveolar Lavage
263
perfusion ratios and shunt. The fall in Pao2 of both groups was similar to that reported by Cole et al. (1980) in a group of patients with chronic pulmonary infections. Alveolar hyperventilation was seen in asthmatics and controls and this contributes to the increased alveolar-arterial oxygen tension difference. The percentage of fluid recovered was similar in both groups. There was no correlation between the decrease in Paop and the amount of lavage fluid retained in the lungs nor with the duration of the procedure. This study suggests that bronchoalveolar lavage induces alterations in pulmonary mechanics and hypoxaemia in both asthmatic patients and controls, the changes being of similar magnitude in both groups. Since these patients had mild to moderate asthma, our findings may not apply to patients with severe asthma or with impaired lung function.
Acknowledgements We thank Prof. T. J. H. Clark for advice and valuable Rodriguez for typing this manuscript.
discussion and Mrs Patricia
References Albertini, R. E., Harrell, J. H., Kurihara, N. & Moser, K. M. (1974) Arterial hypoxemia induced by fiberoptic bronchoscopy. J. Am. med. Ass. 230, 1666. lavage for preparation of free Cole, P., Turton, C., Lanyon, H. & Collins, J. (1980) B ronchoalveolar lung cells: technique and complications. Br. J. Dis. Chest 74, 273. Godard, P., Aubas, P., Calvayrae, P., Taib, J. & Michel, F. B. (1981) Endoscopie et lavage bronchiole-alveolaire chez l’asthmatique allergique. Nouv. Presse Mid. 10, 3141. Neuhaus, A., Markowitz, D., Rotman, H. H. & Weg, J. G. (1978) The effects of fiberoptic bronchoscopy with and without atropine premeditation on pulmonary function in humans. Ann. thorac. Surg. 25, 393.