To elucidate if an effect of propofol on endothelium-dependent relaxation could contribute to propofol-induced vasodilation, smooth muscle relaxation of isolated human omental artery and vein segments precontracted by endothelin-1 were measured. Substance P induced a concentration-dependent relaxation (mean ±SEM) in both artery (63 ± 8.4% of precontraction, n=9) and vein (60 ± 11%, n=7). The relaxation was enhanced by 10−6 M propofol (artery, 72 a 9.5%, n=9; vein, 81 ± 12%, n=7) but not affected by 10−7, 10−5 and 10−4 M propofol. In the presence of Nω-nitro-L-arginine methyl ester (nitric oxide synthase inhibitor), 10−6 M propofol still enhanced the substance P-induced relaxation in arteries but not veins, whereas 10−4 M propofol inhibited the relaxation in both arteries (rightward shift of the concentration-response curve) and veins (28 ± 7.5%, n=8). In the presence of potassium chloride (to prevent hyperpolarization), the enhancement of substance P-induced relaxation by 10−6 M propofol was abolished in both arteries and veins whereas 10−5 and 10−4 M propofol reduced the relaxation in arteries (38 ± 13% at 10−5 M, n=6; 30 ± 11% at 10−4 M, n=6) but not in veins. These results demonstrate that propofol, at lower, clinically relevant concentrations, promotes endothelium-dependent relaxation mediated via hyperpolarization in human omental arteries and via both nitric oxide and hyperpolarization in human omental veins.

It is assumed that diabetic patients with uraemia have more complications at renal transplantation than those who are not diabetic. We compared the preoperative ECGs, and invasive perioperative haemodynamic and oxygenation parameters in 15 diabetic and 15 non-diabetic uraemic patients undergoing renal transplantation. The number of patients with increased QT dispersion in the ECG was higher in diabetic than in non-diabetic patients (P < 0.05). Before anaesthesia, heart rate and mean arterial pressure were higher (P <0.05) in the diabetic than in the non-diabetic group. After preanaesthetic volume loading all patients showed a hyperdynamic circulation, which subsided during anaesthesia. However, stroke volume index remained unchanged. Four patients in the diabetic group and six in the non-diabetic group needed additional oxygen therapy after surgery. No cardiac dysrhythmias were noted. However, the increased QT dispersion in diabetic patients calls for an adequate perioperative ECG monitoring for dysrhythmias. The diabetic and non-diabetic uraemic patients performed equally well at renal transplantation. In conclusion, renal transplantation for diabetics is justified.

The VersaMed 201 is a lightweight, computer-controlled, electrically driven ventilator, designed for transport, home-ventilation and field use. We have evaluated the device in human beings with healthy and pathological lungs. In the first part of the study, the VersaMed was substituted for a standard operating room ventilator for 15–30 min during elective surgery in 20 subjects. In the second stage of the study, 20 patients with lung pathology who were being ventilated in the critical care department were transferred to the VersaMed for a 30-min period. In all the patients studied, arterial blood gases, haemodynamic parameters and other respiratory variables were maintained at similar values seen with the standard ventilators used. We conclude that the VersaMed 201 is suitable for use in human beings with healthy and pathological lungs as a reliable, portable ventilator.

We determined (a) the haemodynamic responses to intubating laryngeal mask (ILM) airway insertion/intubation and removal in anaesthetized patients, and (b) whether the timing of ILM removal influences these responses. One-hundred and twenty patients without cardiovascular disease were studied. ILM airway insertion/intubation was 5 min after induction with propofol 2mg kg−1 and maintenance of anaesthesia with sevoflurane 2% in oxygen 33% and nitrous oxide. Patients were randomly assigned for removal of the intubating laryngeal mask airway at 1, 3 and 5 min after successful intubation. Systolic and diastolic arterial pressures and heart rate were recorded preinduction (baseline), before ILM airway insertion/intubation, at 1-min intervals after insertion/intubation, and at 1-min intervals for 5 min after ILM removal. ILM insertion was successful at the Arst attempt in all patients, but 46 patients required more than one intubation attempt. Compared with baseline values, there were no increases in systolic or diastolic arterial pressure, but there was an increase in heart rate 1 min after ILM insertion/intubation (9%, P < 0.001) and 1 min after ILM removal (8%, P < 0.01). There was a significant increase in systolic and diastolic pressures and heart rate 1 min after ILM insertion/intubation (30%, 31% and 15%; all: P < 0.002) compared with before ILM insertion/intubation values and 1 min after ILM removal (9%, 8% and 7%; all P < 0.05) compared with 1 min after ILM insertion/intubation values. Removal of the ILM 1 min after successful intubation resulted in higher arterial pressure compared with removal at 3 min (systolic arterial pressure 10% higher for 1 min, P=0.01) and 5 min (systolic arterial pressure 10–23% higher for 3 min, P < 0.01; diastolic arterial pressure 10–20% higher for 4 min, P > 0.02), but there were no differences in heart rate between groups. Systolic and diastolic arterial pressures were greater if more than one intubation attempt was required. Early removal or multiple intubation attempts did not exceed baseline haemodynamic values. We conclude that ILM insertion/intubation and removal in anaesthetized patients produces little or no haemodynamic response, even if multiple intubation attempts are required. The timing of removal exerts a small, but clinically unimportant influence on these responses.

A case is presented of a neonate with Hirschsprung's disease, associated with congenital central hypoventilation syndrome. After an ileostomy (at 2 days) and a stoma revision (at 10 days), postoperative pain management was established by continuous intravenous infusion of morphine, which caused severe postoperative respiratory depression. At 6 weeks a reexploration and stoma revision was performed using postoperative epidural analgesia with bupivacaine. This caused no respiratory depression. A colectomy under epidural analgesia at 8 months was also uneventful. Respiratory difficulties in children with congenital central hypoventilation syndrome associated with Hirschsprung's disease are discussed in relation to the technique of choice for postoperative pain management.