G. Rolly

In vitro evaluation of the effect of profound haemodilution with hydroxyethyl starch 6%, modified fluid gelatin 4% and dextran 40 10% on coagulation profile measured by thromboelastography.

Synthetic colloids have been implicated as a cause of coagulopathy when administered in large quantities. The effect of profound haemodilution (50%) on coagulation profile was measured in vitro by thromboelastography. Blood samples were taken from 11 ASA grade 1 patients prior to induction of anaesthesia for elective surgery. Each sample was simultaneously tested in four different preparations: undiluted blood (control sample); blood diluted with hydroxyethyl starch 6%; blood diluted with modified fluid gelatin 4%; blood diluted with dextran 40 10%. There was a significant decrease in reaction time in the preparations treated with hydroxyethyl starch 6% and modified fluid gelatin 4%, reflecting activation of initial fibrin formation. A significant increase in clot formation time was noted in the hydroxyethyl starch 6%‐treated preparations. There was also a significant decrease in clot formation rate and maximum amplitude in the hydroxyethyl starch 6% group. Clot formation time, clot formation rate and maximum amplitude did not change in the modified fluid gelatin 4% group. Profound haemodilution with dextran 40 10% exerted extreme effects on the measured variables, very often resulting in a straight line on the thromboelastography profile.

The position of the patient during neurosurgical procedures on the posterior fossa

SummaryDifferent parameters were measured on patients in six different positions during infratentorial surgery. One group of data served to prove that such patients were in a steady-state as far as their cardiovascular and ventilatory function was concerned. The other measured parameters concerned the intracranial pressure, the intracranial venous pressure and the cerebral perfusion pressure. It appeared from the comparison of these data, that the lateral sitting (45°) position had important advantages and that in this position the possibility of unfavourable features (such as air-embolism) was minimized.

Rapidly progressive pulmonary artery hypertension and end-stage liver disease

Pulmonary hypertension is a recognized but unusual complication of liver disease. It can complicate the perioperative course of liver transplantation. Mild to moderate pulmonary hypertension is generally well tolerated during the procedure and does not appear to contribute to mortality.

Influence of Enflurane on Cerebral Blood Flow in Man

Cerebral blood flow was measured by means of a 10‐channel cerebrograph in anesthe‐tised patients before and during 2% enfluranc. This investigation was carried out after carotid angiography; 2 3 mCi Xe133 was injected into the internal carotid artery. The clearance curves of Xel33 were captured by 10 scintillation counters. In addition to regional cerebral blood flow (rCBF), arterial blood pressure, heart rate, stroke volume, cardiac output and arterial blood gases were measured in seven adult patients.

INFLUENCE OF ENFLURANE ON CEREBRAL BLOOD FLOW IN MAN

Cerebral blood flow was measured by means of a 10-channel cerebrograph in anesthetised patients before and during 2% enflurane. This investigation was carried out after carotid angiography; 2-3 mCi Xe133 was injected into the internal carotid artery. The clearance curves of Xe133 were captured by 10 scintillation counters. In addition to regional cerebral blood flow (rCBF), arterial blood pressure, heart rate, stroke volume, cardiac output and arterial blood gases were measured in seven adult patients. During 2% enflurane, a small, and in two regions a significant decrease in rCBF was observed. Mean arterial pressure and heart rate decreased significantly, but cardiac output did not. The decrease in PaCO2 was not significant.