Acta anaesthesiologica Scandinavica
-
Acta Anaesthesiol Scand · Jan 1977
Comparative StudyThe cerebrovascular CO2 reactivity during the acute phase of brain injury.
Using the intra-arterial 133xenon (133Xe) method, the cerebrovascular response to acute Paco2 reduction was studied in 26 unconscious, brain-injured patients subjected to controlled ventilation. The CO2 reactivity was calculated as delta in CBF/delta Paco2. The perfusion pressure was defined as the difference between mean arterial pressure and mean intraventricular pressure. ⋯ An increase of the CO2 reactivity with time was observed, indicating normal response after 1-2 weeks. Chronic hypocapnia in six unconscious patients resulted in sustained CSF pH adaptation. The question whether a delay in CSF pH adapation exerts an influence on the CO2 reactivity, and the influence of cerebral lactacidosis on the CO2 response are discussed.
-
Acta Anaesthesiol Scand · Jan 1977
Comparative StudyHuman hepatic blood flow and its relation to systemic circulation during intravenous infusion of bupivacaine or etidocaine.
Fifteen healthy young volunteers were studied before and during an intravenous infusion of a local anaesthetic agent. Seven received bupivacaine and eight etidocaine in a dose rate of 2 mg/min over a period of 150 min. Variables of the central systemic circulation and also the hepatic blood flow were measured repeatedly. ⋯ In contrast, these three drugs had the same decreasing effect upon the splanchnic vascular resistance, which caused an almost identical increase in the estimated hepatic blood flow. The calculated vascular resistance in the systemic circulation, excluding the splanchnic, was unchanged during the infusion of etidocaine, while it decreased during the infusion of bupivacaine. Most of this discrepancy was due to the different plasma concentrations of the drugs.
-
Acta Anaesthesiol Scand · Jan 1977
The relationship between disposition and duration of action of congeneric series of steroidal neuromuscular blocking agents.
The renal and hepatic elimination and biotransformation, as well as the relation between disposition and duration of action of pancuronium and two of its analogues, dacuronium and ORG.6368, have been investigated in the cat. In pharmacokinetic studies, appreciable amounts of the latter two compounds were found in the urine, bile and liver 8 h after their intravenous administration. Various proportions of the injected dose of the respective drugs were metabolized. ⋯ The intensity and duration of action of the neuromuscular blocking effect of the three compounds were studied after intravenous and "close" intraarterial injection. On the basis of these pharmacokinetic and neuromuscular studies, it was concluded that the short duration of action of ORG.6368 is due primarily to its early hepatic uptake. The possibility cannot be excluded, however, that differences in the kinetics of the drug action of ORG.6368 and the other two compounds also contributed significantly to the differences seen in the duration of action of these compounds.
-
Acta Anaesthesiol Scand · Jan 1977
Glomerular filtration rate during halothane anaesthesia and epidural analgesia in combination with halothane anaesthesia.
Pre- and peroperative determination of glomerular filtration rate (GFR) was performed in nine patients operated during light halothane anaesthesia (group A) and in nine patients operated during epidural analgesia in combination with light halothane anaesthesia (group B). In group A, the mean GFR decreased insignificantly by 7% and the mean arterial blood pressure increased significantly by 10%. In group B, the mean GFR decreased significantly by 19% and the mean arterial blood pressure decreased significantly by 15%. It is suggested that the difference in change in GFR between the two groups was caused by differences in mean arterial blood pressure.