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Endotoxin [lipopolysaccharide (LPS)] has been reported to reduce hypoxic pulmonary vasoconstriction and thus increases venous admixture. The time course of this failure of pulmonary blood flow regulation was investigated in six chronically instrumented unanesthetized sheep after infusion of Escherichia coli LPS (1 microgram/kg). The change in left pulmonary arterial blood flow (LPBF, ultrasonic transit time) in response to unilateral lung hypoxia (10 min of N2 alternately to the left and right lungs) was compared before and at various time intervals after the administration of LPS. During baseline conditions, LPBF was 33% of total cardiac output and decreased to 15% when the left lung was ventilated with a hypoxic gas mixture. One hour after endotoxin infusion, LPBF remained at 33% of total cardiac output yet only decreased to 28% during the hypoxic challenge. The response to one-lung hypoxia was still significantly depressed 10 h post-LPS administration. It is concluded that hypoxic pulmonary vasoconstriction is almost completely abolished for a prolonged time period after a small dose of LPS.

A total of 267 children scheduled to receive anesthesia during a surgical, neurosurgical, or orthopedic intervention were investigated. IgE antibodies against latex were detected in serum samples of 6.4% (17/267 children) of the patients. The most important difference between sensitized and nonsensitized children was the number of surgical interventions in the past. The median of surgical interventions was 1.0 in the nonsensitized group of children and 3.0 in the sensitized group. Only 0.9% of the children with up to two surgical interventions and 34.1% with three or more procedures were sensitized to latex. Only one of the sensitized children developed intraoperative anaphylaxis during intervention after our investigation. We conclude that children with a history of three or more surgical interventions have a high risk of sensitization to latex proteins. Nevertheless, the predictive value of IgE antibodies against latex for development of anaphylaxis during anesthesia seems to be low.

We investigated whether different procedures during general anaesthesia alter platelet activation in vivo and/or activate coagulation and fibrinolysis. Forty-one healthy adult patients, scheduled for elective ophthalmic surgery under general anaesthesia, were studied with regard to changes of plasma beta-thromboglobulin (beta TG, index of platelet activation), thrombin-antithrombin III-complex (TAT, index of activation of coagulation) and d-dimer (index of fibrinolysis) during anaesthesia. The patients underwent either inhalation anaesthesia with enflurane and nitrous oxide or balanced anaesthesia with enflurane (0.5% end-tidal concentration) and alfentanil. Ten minutes after intubation the beta TG level was significantly reduced compared to the preoperative value in both general anaesthesia groups. Balanced anaesthesia caused a moderate but significant increase of TAT values at 10 min after extubation. No significant change in d-dimer levels was seen. Presuming a minimal effect of the surgical procedure on the determined variables, we conclude that none of the anaesthetic procedures induces platelet activation and fibrinolysis. The clinical relevance of the moderate coagulation activation during balanced anaesthesia remains to be investigated.