경희의료원 마취통증의학과 R3 전주연 British journal of anaesthesia. 2005;94:778-83 Comparison of propofol/remifentanil and sevoflurane/remifentanil for maintenance of anaesthesia for elective intracranial surgery 경희의료원 마취통증의학과 R3 전주연 British journal of anaesthesia. 2005;94:778-83

Background IV and inhalation agents are in general use for maintenance of anesthesia during neurosurgery Comparisons btw iv and inhalation have been inconclusive Remifentanyl – rapid onset, promptly elimination, low instance of pain No published reports, compare sevo/remi and propofol/remi in neurosurgery

Methods Fifty pts. Undergoing elective craniotomy Double-blind design- rejected (easy detection of sevoflurane by smell) Arterial pressure- direct measurement from the radial a. and stored at 1-min intervals Hypertension and hypotension by inspection of the stored electronic record

Method-Anaesthesia Remifentanyl Group P (propofol anesthesia) Bolus- 1μg/kg Infusion- 0.5 μg/kg – 0.25 μg/kg after craniotomy Group P (propofol anesthesia) TCI (Target controlled infusion) of propofol Initial plasma conc. – (1 μg/ml) was increased progressively until satisfactory anesthesia Maintained by the TCI with a minimum target conc. Of 2 μg/ml

Method-Anaesthesia Group S (sevoflurane anesthesia) Bolus injection propofol- 0.5mg/kg c supplementary doses of 10mg every 10s until loss of consciousness Maintain Initial ET conc. 2% minimum conc. 1% Tracheal intubation Atracurium as bolus and followed by an infusion until dural closure Normocapnia Fresh gas flow – 0.5L/min O2, 1.0L/min Air

Method-Anaesthesia Remifentanyl infusion stopped after skin closure Sevoflurane and propofol were continued until head bandaging was completed Mannitol 1g/kg – given bt induction of anesth. And craniotomy Surgeon – state of brain(tight, adequate, soft) Dose of mannitol was recorded

Method-Anaesthesia Hypertensive episode Hypotensive episode MAP > 100mmHg for more than 1min Treated c remi 1 μg/kg and infusion rate increased by 0.125 μg/kg/min Labetolol or hydralazine was given Hypotensive episode MAP < 60mmHg for more than 1min Reducing the propofol target or sevoflurane conc. Vasopressor was administered if necessary

Method-Anaesthesia Time to adequate respiration, extubation, eye opening and obey commands Analgesia was provided by bolus injections of morphine 2mg Nausea and vomiting and the discharge time were recorded.

Method-Statistical analysis Statview and excel v. 7 Continuous variables Mann-Whitney U-test Categorical valuables chi-squared test P < 0.05 – statistically significant Drug acquisition costs post-hoc

Results Group P (24pt.) Group S (26pt.) Remifentanil infusion rate Propofol infusion rate 5.45 mg/kg/h Group S (26pt.) 1.06mg/kg propofol for induction ET conc. Of sevo. 1.13 % Remifentanil infusion rate Similar in the two group Aaesthesia time Longer in group P – difference was not significant

Results Hypertensive episodes Hypotensive episodes Arterial pressure before, during, and after surgery was similar. Hypertensive episodes 7 and 8 pt. in group P and S No significant difference (P=0.374, chi square) Labetolol 14 and 19pt in group P and S Hydralazine 2 and 5 pt in group P and S Hypotensive episodes 15 and 23 pt in group P and S No significant difference Ephedrine 63 and 88% pt in group P and S Total dose of ephedrine 4.8 and 9.8 mg in group P and S

Results Time to spontaneous respiration Shorter in group P and S(P=0.02) Time to eye opening, extubation, obeying commands were not statistically significant Relationship btw. Recovery time and hypotensice episodes Were not significantly correlated Requirement for morphine, dosage of morphine, incidences of N/V and recovery room stay were similar

Results Total hypnotic , analgesic drug and vasoactive drug acquisition costs Group P > Group S (19.31 > 15.52/h) Significantly high ( P= 0.016)

Discussion Sevoflurane and propofol in combination with remifentanil Satisfactory agents for maintenance of anaesthesia in neurosurgical patients. Increased number of hypotensive episodes in group S Group S simply more deeply anaesthetized CP50 of propofol – 5.45μg/ml IC50 of sevo – 1.14% Average target propofol conc. – 3.67 μg/ml Average ET sevo conc. – 1.13%

Discussion Small and clinically unimportant differences in recovery bt Group P and Group S Many reports to compare recovery characteristics Sevoflurane gave faster, similar, or slower recovery than propofol anesthesia Ex) Yli-Hankala – no difference of recovery Evaluation whether hypotensive episodes were associated with delayed recovery – No correlation

Discussion PONV Small difference in drug acquisition costs Many studies – sevoflurane caused PONV more frequently than propofol anesthesia. PONV – 30% of patients receiving sevoflurane PONV occurred in only 15% of patients with no difference between propofol and sevoflurane Small difference in drug acquisition costs Difference are very small in relation to the total cost of a neurosurgical procedure

Discussion Both agents were satisfactory Realistic doses of propofol and sevoflurane Recognize the strong synergism bt. these agents and remifentanil. Common clinical doses of remifentanil Substantial sparing of sevoflurane and propofol Previous study – propofol infusion rate 100μg/kg/min – too high We have carefully evaluated sevo, and propofol as maintenance agents with remifentanil for elective intracranial surgery. Both agents were satisfactory