Antroduodenal motility, pH and gastric emptying rate were measured in 11 patients undergoing orthopaedic or plastic surgery with general anaesthesia. Motility was measured by manometry and gastric emptying rate by the rate of paracetamol absorption. During anaesthesia, gastric emptying was delayed in eight patients. General anaesthesia with halothane reduced the duration of the interdigestive motility complex (P less than 0.01), mainly by a shortening of phase II (P less than 0.01) which correlated with the inhaled concentrations of halothane (P less than 0.01). Anaesthesia impeded the occurrence of antral contractions during phase II (P less than 0.01); the frequency of contractions was unchanged during anaesthesia, but decreased during the recovery period (P less than 0.01). The amplitudes of antral contractions diminished with anaesthesia (P less than 0.01), but increased after operation. The frequency of contractions in the duodenum was unchanged during phase II and reduced during phase III (P less than 0.01). Gastric pH increased during and after operation (P less than 0.01). General anaesthesia with halothane affects gastroduodenal motility especially during phase II, increases gastric pH and delays gastric emptying rate.

A total of 434 patients admitted to the intensive care unit for mechanical ventilation were followed prospectively to investigate the influence of a nasotracheal tube on the paranasal sinuses. Twenty-five patients died before the examination was completed. The rest were examined for clinical symptoms of sinusitis. If sinusitis was suspected or the patients were intubated for 5 days or more, an x-ray of the sinuses was performed. In patients intubated for less than 5 days (N = 357), sinusitis was clinically suspected in three, but radiographically verified in only one. In patients intubated for 5 days or more (N = 47), 23 (49%) had affection of the paranasal sinuses. Patients needing a nasotracheal tube should be examined for sinusitis if they are intubated for more than 5 days or if unexplained fever, sepsis or purulent nasal secretion develops. If the suspicion is confirmed, the nasotracheal tube should be removed.

Since data on velocity fields in the ascending aorta downstream of normal aortic valves in pigs have not yet been obtained velocity profiles were visualised using a hot film anemometer needle probe before and after total cardiopulmonary bypass and cold cardioplegic arrest. Furthermore, measurements were made during increased heart rate and cardiac output. A dynamic three dimensional visualisation of velocity fields showed a skewed clockwise rotating velocity profile, developing from peak systole and continuing throughout the systolic deceleration phase. This pattern was consistent regardless of the haemodynamic state. Heart rate was increased to 180 beats.min-1 and cardiac output by a maximum of 91%. It is concluded that the pig model is valuable for haemodynamic studies in the ascending aorta before and after cold cardioplegic arrest and that the velocity profiles found in this study are important basic data for velocity field studies downstream of artificial heart valves implanted in the aortic position.

In the postoperative period fifty-six healthy patients undergoing cholecystectomy or operations for duodenal ulcer, received, in a randomized order, i.m., "high-level" or "low-level" extradural morphine. Thirty-five per cent in the i.m. group, 33% in the high-level group and 50% in the low-level group suffered urinary retention, in all cases within the first 24 h. The mean cumulative dose of morphine necessary for pain relief was in the same range (13.4-16.5 mg) during the first 2 h of therapy for all groups, while the amounts after 24 and 48 h were twice to four times with the i.m. route compared with the extradural route. A peripheral effect of morphine on the urinary bladder is possible and the mechanism of action is discussed.

The effects of diazepam on antroduodenal motility, gastric pH and gastric emptying rate were investigated in 10 volunteers. Gastric emptying was assessed using paracetamol absorption and antroduodenal motility and pH by means of a perfused multilumen tube. On the first study day, the volunteers received paracetamol in phase I after the occurrence of one complete interdigestive motility complex (IDMC). Diazepam was given on the second study day at the beginning of the first phase I and paracetamol was given one IDMC later. The rate of absorption correlated with motility (P less than 0.03). Some volunteers were fast absorbers on the first study day and slow on the second, indicating that absorption rate is not constant, but dependent on gastroduodenal motility. Diazepam tended to increase the gastric emptying rate and enhanced the amplitude of contractions and the motility index during phase II (P less than 0.02). Gastric pH increased after ingestion of diazepam (P less than 0.05).