Wpływ propofolu na prędkość przepływu krwi w tętnicy środkowej mózgu (VMCA) u chorych z niepękniętym tętniakiem wewnątrzczaszkowym podczas indukcji znieczulenia ogólnego

Abstract

Background: The estimated prevalence of unruptured intracranial aneurysms is 3%. Standard monitoring does not enable one to assess the influence of anaesthetics on the factors determining intracranial homeostasis. Thanks to transcranial Doppler ultrasonography, middle cerebral artery flow velocity (V MCA), reflecting cerebral blood flow, can be measured. The aim of the study was to assess the effects of propofol on intracranial homeostasis in patients with unruptured intracranial aneurysms during the induction of anaesthesia based on V MCA changes. Methods: The study encompassed 21 patients (group II) anaesthetised for elective craniotomy due to unruptured intracranial aneurysms. The control group (group I) included 21 patients who underwent discoidectomy. V MCA , as well as HR, MAP, etCO 2 , and SpO 2 were monitored at the following time points: T 0 -onset of study; T 1 -after 1 minute; T 2 -onset of preoxygenation; T 3 -after 1 minute of preoxygenation; T 4 -administration of fentanyl; T 5 -1 minute after fentanyl; T 6 -administration of propofol; T 7 -1 minute after propofol; T 8 -intubation; T 9 -1 minute after intubation; T 10 -2 minutes after intubation. results: In both groups, no changes in mean HR, etCO 2 and SpO 2 were observed at the successive time points of observation. In groups I and II, an MAP decrease between T 6 and T 7 and an MAP increase between T 7 and T 9 were noted. There were no intergroup differences in mean values of MAP at the times of observation. In both groups and bilaterally, a V MCA decrease was recorded between T 6 and T 7 and an increase between T 7 and T 8 . There were no intergroup differences in mean values of V MCA at the times of observation. In both groups, a weak correlation between V MCA and MAP changes was found bilaterally. Conclusions: Propofol depresses the cerebral circulation during the induction of anaesthesia. The presence of an unruptured aneurysm does not affect the reactivity of the cerebral vessels during the induction of anaesthesia with propofol.

Comparison of cerebral blood flow during general anesthesia in elderly patients with and without dementia: a prospective controlled clinical trial

“…Meanwhile, 60% of the brain's energy expenditure contributes to electrophysiological functions, and the cerebral metabolic rate (CMR) is related to CBF [39]. MAP and CBF (middle cerebral artery ow velocity) have been reported to be correlated during anesthesia in a study of patients with an average age of 51 years [40], and that in the anesthesia using propofol (1-2 mg/kg), remifentanil (anesthesia induction with 1 µg/kg/min and maintenance using 0.1 µg/kg/min), and sevo urane (< 1 minimum alveolar concentration [MAC]), the MAP and degree of expansion of the internal carotid and middle cerebral arteries are correlated [41]. These reports suggest that MAP and CBF are correlated even under anesthesia.…”