Pharmacokinetics of sevoflurane uptake into the brain and body

Abstract

SummaryThe aim of this study was to investigate the pharmacokinetics of sevoflurane uptake into the brain and body by comparing sevoflurane concentrations in internal jugular-bulb blood (Jsev), arterial blood (Asev) and pulmonary arterial blood (PAsev) over a fixed inspired sevoflurane concentration. Ten patients (aged 51-73 years), undergoing coronary artery bypass grafting surgery were enrolled in this study. They were anaesthetised using a constant 3.5% inspired sevoflurane concentration (C I sev) during the first hour of anaesthesia. During constant volume-controlled ventilation, we measured C I sev and end-tidal sevoflurane (C E sev) using infrared analysis. The sevoflurane concentration in the blood was analysed using gas chromatography, and cardiac output was measured using an Opti-Q pulmonary artery catheter. We found that it took 40 min for the brain concentration to equilibrate with arterial blood (Asev). Both C I sev-C E sev and Asev-PAsev gradients persisted during the study period. There was no further uptake of sevoflurane into the brain after 40 min; however, there was near-constant uptake into the body. Sevoflurane is widely used in clinical anaesthesia because of its relative lack of airway irritation or myocardial suppression effects. It has rapid induction and emergence characteristics compared with other available inhalation anaesthetic agents [1][2][3]. Sevoflurane, has a low blood ⁄ gas solubility coefficient and has been thought to have rapid uptake pharmacokinetics in human volunteers [4,5]. The brain ⁄ blood partition coefficient of volatile anaesthetics is important in determining the rate of brain tissue wash-in and wash-out, and wash-in and wash-out characteristics are the main determinants of the rate of induction of and recovery from anaesthesia.The uptake pattern of sevoflurane remains poorly quantified and its uptake into the brain and body has not yet been fully elucidated. However, it has been shown that there is a well-defined relationship between volatile anaesthetic partial pressure in the brain and anaesthetic effects [6,7]. The aim of inhalation anaesthesia is to produce, safely and conveniently, a partial pressure adequate for anaesthesia. The aim of this study was to establish the time required for sevoflurane changes in arterial blood (Asev), right internal jugular-bulb blood (Jsev) and pulmonary arterial blood (PAsev) under constant inspired concentrations of sevoflurane during the first hour of anaesthesia. The primary purpose of this study was to explore the relationship among end-tidal sevoflurane concentrations (C E sev), Asev, PAsev and Jsev at a fixed inspired sevoflurane concentration during the first hour of sevoflurane anaesthesia. Second, we compared the different uptake patterns of sevoflurane in the Anaesthesia, 2003, 58, pages 951-956

Pharmacokinetics of Isoflurane in Human Blood

“…A 2% inspired concentration of isoflurane in 6,000 ml min -1 oxygen flow was administered to wash in functional residual capacity for 5 min, and then the oxygen flow rate was reduced to 300 ml min -1 for the maintenance of minimal-low-flow anesthesia [9,10] , which provided 1.5-2.5% inspired isoflurane concentration according to the dynamic status and the surgical stimuli. After intubation, a single-lumen central venous catheter and a pulmonary arterial catheter were inserted into the right internal jugular bulb and pulmonary artery, respectively, for blood sampling [5,6,11,12] . The cardiopulmonary bypass (CPB) set up was uniform for all patients, namely with a crystalloid prime, a Medtronic membrane oxygenator, moderate hypothermia (28 ° C), hemodilution to a hematocrit of 20-25%, and alpha stat pH management.…”

“…An esophageal thermistor was applied to measure body temperature, which was maintained at 35.5-37.5 ° C during the study. Cardiac output was continuously measured using the Opti-Q catheter (Abbott Critical Care System, Mountain View, Calif., USA) with the Q-Vue continuous cardiac output computer (Abbott Critical Care System) [11,12] .…”

Sevoflurane Elimination and Hystopathological Changes in Lung, Liver, Kidney and Brain Tissues

“…Bu ne den le de se vof lu ra nın eks tra he pa tik eli mi nas yonu araş tır ma ko nu su ol ma ya baş la mış tır. 11,13,14 Da ha ön ce yap tı ğı mız bir ça lış ma da se vof luran ın in vi vo me ta bo liz ma ve eli mi nas yo nu nu kara ci ğer, böb rek, ak ci ğer, gas tro in tes ti nal sis tem, yu mu şak do ku lar ve san tral si nir sis te min de, eş zaman lı alı nan kan, id rar, saf ra ve do ku ör nek le rin de inor ga nik flor öl çüm le riy le in ce le miş tik. Bu ça lış -ma mı zın so nu cun da se vof lu ra ne'ın te mel me ta boliz ma sı nın ka ra ci ğer de ol mak la bir lik te, böb rek te de önem li öl çü de def lu ri nas yo nun ger çek leş ti ği ni sap ta mış tık.…”

A prospective randomized study for comparison of haemodynamic changes and recovery characteristics with propofol and sevoflurane anaesthesia during laparoscopic cholecystectomies

“…11 Sevoflurane is also widely used as an inhalational induction agent as it is pleasant to inhale and has less airway irritation with low blood gas partition coefficient which contributes to more rapid induction and emergence from anaesthesia than with other volatile anaesthetics in clinical anaesthesia. 12,13 So both propofol and sevoflurane have smooth and rapid anaesthetic induction and maintenance with shorter recovery providing adequate anaesthetic conditions for day care anaesthesia. 13 This study was designed and based on the hypothesis that using the less soluble volatile anaesthetic agent, sevoflurane, can be used as a better alternative to propofol for maintenance of anaesthesia in patients undergoing laparoscopic cholecystectomy in day care anaesthesia.…”

“…12,13 So both propofol and sevoflurane have smooth and rapid anaesthetic induction and maintenance with shorter recovery providing adequate anaesthetic conditions for day care anaesthesia. 13 This study was designed and based on the hypothesis that using the less soluble volatile anaesthetic agent, sevoflurane, can be used as a better alternative to propofol for maintenance of anaesthesia in patients undergoing laparoscopic cholecystectomy in day care anaesthesia.…”