Haemodynamic and EEG changes during rapid-sequence induction of anaesthesia

Abstract

The relationship between the changes in haemodynamic function and the electroencephalogram (EEG) during rapidsequence induction of anaesthesia was studied in 15 ASA I patients. Anaesthesia was induced with a bolus thiamylal (5 mg" kg -l iv)followed by succinylcholine (1 mg" kg-~). Tracheal intubation was attempted one minute after the injection of suc Aprds lfntubation trachdale, la PAs augmente de 44% au dessus de la valeurs post-induction (P < 0,05) et en m~me temps I'AE augmente~ 13,1 Hz (P < O, 05). En conclusion, i 'induction sdquentielle rapide avec le thyamilal (5 mg" kg -t) produit une ddpression de l'activitd cdrdbrale rdvdlde par i'EA, alors que la laryngoscopie et i'intubation augmente cette activitd. Ceci montre qu'avec une induction d sdquence rapide cette dose de thiamylal pourrait &re insuffisante pour lbbtention d'un niveau d'anesthdsie addquat et l'abolition des rdponses hdmodynamiques de l'intubation.Rapid-sequence induction of anaesthesia is now frequently used for emergency patients. Various sequences have proved effective, but all tend to cause broad haemodynamic fluctuations. I These responses sometimes lead to fatal damages in patients with hypertension, ischaemic heart disease, intracranial aneurysm, or increased intracranial pressure. Many studies have used the electroencephalogram (EEG) in an attempt to measure the effect of anaesthesia on the cerebral cortex. However, to the authors' knowledge, there have been no simultaneous investigations of the EEG and haemodynamic responses during rapid-sequence induction of anaesthesia. Recently, on-line computerized aperiodic analysis of the EEG was used to assess the depth of anaesthesia in highdose fentanyl anaesthesia.2 The purpose of this study was to determine whether one of these devices, the Lifescan~ EEG Monitor (Neurometrics~, San Diego, CA) provides useful additional information about cerebral responses during rapid-sequence induction. Methods

Attenuation of the pressor responses to laryngoscopy and endotracheal intubation with intravenous dexmedetomidine versus magnesium sulphate under bispectral index-controlled anaesthesia: A placebo-controlled prospective randomised trial

“…Since laryngoscopy and endotracheal intubation, similar to any other peripheral noxious stimulus, might produce a reflex response in the reticular activating system of brainstem, it can lead to wakefulness, making the planes of anaesthesia lighter. [ 11 ] Hence, maintaining the BIS values at 40–50 during the induction of anaesthesia may prevent such responses.…”

Hemodynamic and bispectral index responses to tracheal intubation during isoflurane or sevoflurane anesthesia

“…However, peripheral noxious stimuli reach the brain through the ascending reticular activating systems of the brain stem [16]. Mi et al [3] reported that BIS was significantly increased by laryngoscopy and intubation during the infusion of propofol with or without fentanyl pretreatment.…”