The influence of intraoperative cerebral electrical activity on postoperative analgesia in obese patients

M. Popescu¹, G. Gurman², A. Porrath², E. Avinoah², O. Steiner²
1. Secţia ATI, Spitalul Elias Bucureşti
2. Departamentul ATI; Soroka University Medical Center; Beer-Sheva, Israel

Abstract

In 71 obese patients operated for gastric banding under isoflurane administration, the anaesthesia was conducted on clinical signs and standard monitoring.
Concomitently, the EEG spectral edge frequency (SEF 90) was monitored by an independent investigator. The anaesthetic dosage, the level of postoperative analgesia and the postoperative opioid consumption were measured.
Postoperatively the results were evaluated according to the intraoperative evolution of SEF 90. It was found that in 38 patients (53.3% of total), SEF 90 was maintained between 8 and 12 Hz, a period above 80% of the duration of anaesthesia (study group 1) and, that in 33 patients (46.5%) SEF 8-12 Hz was maintained a period less than 80% of the duration of anaesthesia (study group 2). The patients from group 1 were haemodynamically more stable intraoperatively and had less pain and required less opioids postoperatively, than the patients from group 2. The results correlated with an increased isoflurane consumption in the group 1 versus group 2. In conclusion, intranaesthetic monitoring of SEF at values between 8-12 Hz is useful to assure an adequate anaesthetic depth and a reduced postoperative pain in obese patients.

Key words: depth of anaesthesia, SEF90, obese patients, postoperative pain

Jurnalul Român de Anestezie Terapie Intensivă 2003 Vol.10 Nr.1, 17-21

Influenţa stabilităţii electrice corticale intraoperatorii asupra analgeziei postoperatorii la pacienţii obezi