Bronchoscopy and BAL in mechanically ventilated patients in an ICU at a university teaching hospital

Introduction

Bronchoscopy is an important diagnostic and therapeutic tool in modern intensive care medicine. In ventilated patients it can lead to hemodynamic instability and can compromise the gas exchange.

Method

We evaluated in a prospective study from 3/1997 to 9/1998 indications, complications and side effects of bronchoscopy in a 12 bed medical lCU. The vital signs of the patients were monitored continuously by ECG, invasive blood pressure and S_aO₂), measurement. A BGA was performed 5 min before and 5/30/120 min after the examination.

Results

One hundred and fifty-one bronchoscopies were performed in 103 patients (63 male, median age 60 years, median APACHE II-Score 27.5). The indications were bacteriological examinations in 113/151 (75%), respiratory toilet in 29/151 (19%), oxygenation problems in 11/151 (7%). Less common indications were atelectasis, intubation and biopsy. A BAL was performed in 111/151 (74%) cases. The median P_aO₂/F_iO₂-ratio (PER) was 292 mmHg 5 min before bronchoscopy and 254/182/193 mmHg 5/30/120 min afterwards. In the subgroup with BAL the median PFR was 295 mmHg 5min before, 5/30/120 min after examination 261/181/194 mmHg. The PFR was in the critical range <80 mmHg before bronchoscopy in 5/151 (3%) and 5/30/120 min after the examination in 5/151 (3%), 9/151 (6%) and 7/151 (5%) cases. In patients with BAL, the corresponding figures were 2/111 before and 3/111, 6/111, 4/111 after bronchoscopy. A decrease of the PFR between the beginning and 30 min after finishing bronchoscopy by more than 50 mmHg was observed in 59/151 (39%) cases for all patients, in 50/111 (45%) for the BAL subgroup. During 5/151 (3%) procedures serious complications were observed. An increase of the blood pressure (215/120 mmHg max.) after local application of noradrenalin and a high peak pressure during ventilation (>45 Torr) did not need therapy. A tachyarrhythmia absoluta was treated by cardioversion. A decrease of systolic arterial blood pressure (min. 67 mmHg) during sedation, could be stabilised by volume substitution and dopamine infusion. Bundle-branch block like ventricular complexes were observed on the ECG monitor in one case, which were accompanied by a blood pressure decrease. After an interruption the ECG showed sinus rhythm and the hemodynamic stabilised again. In a 24 h period after bronchoscopy the patient died because of an acute myocardial infarction.

Conclusion

Bronchoscopy is a safe procedure in critical ill mechanically ventilated patients. Even in patients with BAL, in the most cases only a slight decrease of the PFR could be observed. The lowest PFRs were observed 30 min after bronchoscopy, 90 min later the PER was almost back to the starting level. Critical PaO₂ values were only seen in rare cases. Complications could be handled in all cases. The death of one patient in a 24 h range after bronchoscopy was probably caused by the underlying disease and is to be seen only in temporal coincidence.