SummaryAviation's 'sterile cockpit' rule holds that distractions on the flight deck should be kept at a minimum during critical phases of flight. To assess current practice at comparable points during obstetric regional anaesthesia, we measured ambient noise and distracting events during 30 caesarean sections in three phases: during establishment of regional anaesthesia; during testing of regional blockade; and after delivery of the fetal head. Mean (SD) noise levels were 62.5 (3.9) dB during establishment of blockade, 63.9 (4.1) dB during testing and 66.8 (5.0) dB after delivery (p < 0.001). The median rates of sudden, loud (> 70 dB) noises, non-clinical conversations and numbers of staff present in the operating theatre increased during each of the three phases. Conversely, entrances into, and exits from, theatre per minute were highest during establishment of regional anaesthesia and decreased over the subsequent two time periods (p < 0.001).

No abstract

In contrast with the widely investigated electrocardiographic (ECG) changes accompanying endotracheal intubation, very few reports have appeared on the changes that occur during the course of bronchoscopic procedures. Burman and Gibson 1 investigated the ECG changes during bronchoscopy conducted under local anasthesia and Van Nouhuys2 reported his findings on a small series of bronchoscopies performed under general anaesthesia. In both these series, spontaneous respiration continued, so that it is reasonable to suppose that the arterial carbon dioxide tension (Pco~) was reasonably near normal.The use of the technique of apnoeic oxygenation during general anasthesia for bronchoscopy has advantages which commend it as the routine method for adult bronchoscopy 3. It does, however, lend itself to the criticism of an inevitable increase in Pco2. Hypercapnoea has long been known to cause an increase in the incidence of arrhythmias occurring under anasthesia and for this reason continuous electrocardiographic monitoring was undertaken on a series of fifty patients undergoing routine bronchoscopy with the apnoeic oxygenation technique. The results were compared with those reported by the workers mentioned above, in order to assess the relative incidence of cardiac arrhythmias using this anaesthetic technique. M A T E R I A LThe 50 patients investigated were unselected and were for the most part consecutive. The majority were out-patients referred from chest clinics and other hospitals, with a minority of in-patients. Most of the bronchoscopies were performed for diagnostic purposes : a few were therapeutic for such conditions as sputum retention and atelectasis. Most of the patients were in good general condition, but some of those treated by therapeutic bronchoscopy were in poor or very poor condition. The sex and age incidence is shown in table 1. 449

No abstract