DOI: 10.1097/00000539-199802001-00485
,
Issn Print: 0003-2999
Publication Date: 1998/02/01
Facebook
Twitter
LinkedIn
Email
 |
Checking for direct PDF access through Ovid | |
Excerpt
Remifentanil (R), is an extremely potent, [micro sign]-receptor selective agonist, esterase-metabolized opioid with an elimination half-life of 8-10min. [1] These characteristics would permit profound intraoperative analgesia whilst allowing rapid recovery without risk of postoperative respiratory depression. The aim of this study was to investigate whether these effects are influenced differently by the addition of isoflurane (I), propofol (P) or enflurane (E), of which the latter has not been studied in combination with remifentanil before. We compared the effectiveness, recovery and safety following anesthesia with R+I, R+P or R+E.
METHODS: This study comprised two identical protocols co-ordinated centrally across 75 centers in 14 countries. Following institutional approval and informed consent, 854 patients (52% daycase: 48% inpatient) ASA class I-III undergoing gynecological laparoscopy, varicose vein or arthroscopic surgery were randomized to open block-balanced treatment with R+I, R+E or R+P.
Anesthesia was induced with a bolus of R (1 [micro sign]g/kg) and a bolus of P (1mg/kg) and a preintubation infusion of R at 0.5 [micro sign]g/kg followed by a routine neuromuscular blocking agent. R infusion was reduced by 50% 5min after endotracheal intubation. Anesthesia was maintained with initial end tidal I or E at 0.5 MAC and P infusion of 100 [micro sign]g/kg/min. Hemodynamic [hypertension (SBP>15mmHg over baseline)>or=to1min or tachycardia (HR>90 bpm)>or=to1min], somatic and autonomic responses during surgery were treated with single R boluses (1 [micro sign]g/kg) or R bolus plus R infusion increase. For hypotension (SBP<80 mmHg>or=to1 min) R infusion was reduced. Bradycardia (HR<40bpm>or=to1min) was treated with an anticholinergic. Postoperative pain management, was initiated with intraoperative NSAID and the surgical wound infiltrated with a local anesthetic.
Endpoints included: response to endotracheal intubation and skin incision; responses from start to end of surgery; hypotension; bradycardia; recovery; qualification for and actual Phase I and II discharge times. R, P, I, and E were switched off at last suture.
RESULTS: Median time to loss of consciousness was 2 min for all three groups. All three regimens provided good intraoperative anesthesia. (Table 1)
CONCLUSIONS: The intraoperative analgesia demonstrated in this study is normally only achieved using high-dose opioid anesthesia which can often result in prolonged recovery times. In contrast, however, emergence from R-based anesthesia with I,E or P was extremely consistent and rapid in all three groups demonstrating the short offset of the effects of R.
