Total intravenous anesthesia with propofol and remifentanil for elective non-cardiac surgery.
BACKGROUND: Remifentanil is a highly effective mu opioid agonist with predictable pharmacokinetics and a close concentration-effect relationship. Moreover, studies on anesthetic drugs interactions show that optimal propofol concentrations decrease more significantly with remifentanil as compared with other opioids and recovery appears to be much faster than when propofol is combined with other opioids combinations. This intervention study was designed to evaluate the efficacy of propofol combined with remifentanil in elective non cardiac inpatient surgery. METHODS: N. 405 patients undergoing intraperitoneal, head-neck, intrathoracic, major orthopaedics, breast and major vascular surgery received: remifentanil (1 microgram.kg-1 at induction; 0.50 microgram.kg-1.min-1 at laryngoscopy; 0.25 microgram.kg-1.min-1 at skin incision; 0.25-0.30 microgram.kg-1.min1 from skin incision to end of skin suture) and propofol (0.5-1 mg.kg-1 at induction; 5 mg.kg-1.h-1 at laryngoscopy; 5 mg.kg-1.h-1 at skin incision and 5 mg.kg1.h1 thereafter). Intraoperative end-points included somatic responses, tachycardia and hypertension to laryngoscopy and surgery. Incidence of intraoperative bradycardia, hypotension and muscle rigidity were also recorded. Postoperative end-points included Aldrete score > or = 9, pain immediately following emergence and PONV. RESULTS: Propofol-remifentanil combination effectively controlled responses to laryngoscopy and surgical stress. Drug related adverse events were transient bradycardia (< 50 bpm) and hypotension (SBP < or = 80 mmHg) respectively: at prelaryngoscopy 11.60-1.48% and at pre-skin incision 10.61-0.98%. N. 365 patients were discharged from PACU and the median time to first Aldrete score > or = 9 was 22.3 min. The most frequent postoperative event was shivering recorded in n. 46 patients (12%). Postoperative analgesic medication was requested by n. 16 patients (4.4%) and PONV was noted in n. 6 patients (1.6%). CONCLUSIONS: When combined with propofol, remifentanil effectively provided for profound analgesia during surgery, stable anesthetic conditions, simplicity of use and predictable recovery.