Comparison of recovery profile for propofol and sevoflurane anesthesia in cases of open cholecystectomy.

OBJECTIVE: Sevoflurane and propofol are considered to be the agents of choice in surgeries of short duration due to their better recovery profile and few post-operative complications. This study was designed to compare the early recovery profile of sevoflurane and propofol anesthesia in patients undergoing open cholecystectomy.
MATERIALS AND METHODS: A total of 60 patients of either sex with American Society of Anesthesiologists grade 1 and 2 scheduled for elective cholecystectomy were prospectively randomized into two groups. Group S (30 patients) were maintained with sevoflurane anesthesia (1-2%), while in Group P (30 patients) were maintained with propofol infusion (75-125 μg/kg/min) in both the groups the anesthetic concentration/dose was so adjusted to keep hemodynamic parameter (mean arterial pressure and heart rate) within 15% of their respective baselines values.
RESULTS: It was observed that there was no significant difference (P > 0.05) between there early recovery profile that includes spontaneous eye opening (7.5 ± 1.6 min for sevoflurane group and 6.9 ± 1.7 min for propofol group), following simple verbal command (9.2 ± 2.2 min for sevoflurane group and 8.9 ± 1.9 min for propofol group) and extubation time (10.7 ± 2.3 min for sevoflurane group and 10.3 ± 2.0 min for propofol group) but there was a significant difference (P < 0.05) in incidence of post-operative nausea and vomiting (PONV) in both groups.
CONCLUSION: Propofol is as good as sevoflurane for maintenance of anesthesia in surgeries like open cholecystectomy with an added advantage of lower incidence of PONV owing to its intrinsic antiemetic properties.

RCT Entities:   Population Interventions Outcomes

INTRODUCTION

In hepatobiliary surgeries of short to moderate duration, it is always desirable to have quick regained of consciousness with minimal post-operative sickness.

By virtue of its kinetic properties, propofol has become the preferred intravenous (IV) anesthetic agent for surgeries, which are of short duration and requires a rapid and clear headed recovery. It has some antiemetic properties as well.

Sevoflurane, a newer halogenated volatile anesthetic agent with relatively low blood-gas partition coefficient causes faster induction and the emergence with stable hemodynamic. It has become inhalational agent of choice in the pediatric age group, being pleasant to inhale.

As the recovery characteristics of propofol are comparable with many newer inhalational agents, it is therefore desirable to design a study that compare the frequency of post-operative nausea and vomiting (PONV) and recovery profile of propofol and sevoflurane based anesthesia.

MATERIALS AND METHODS

This prospective, randomized and blinded clinically controlled study was conducted on 60 American Society of Anesthesiologists (ASA) I and II patients, aged between 18 and 55 years. After taking the approval from ethical committee and written informed consents, patients were randomly allocated into two groups of 30 each according to a computer generated list of random numbers. Patients allergic to any of the agent to be used were excluded from the study. Pregnant and lactating women were also excluded.

All study patients were pre-medicated (IV route) with injection Glycopyrrolate 4 μg/kg and injection Midazolam 0.025 mg/kg. Injection Fentanyl 2 μg/kg. IV was given to all patients just before induction. On OR table, monitors were connected and baseline parameters, i.e., heart rate (HR), blood pressure, oxygen saturation, end-tidal carbon dioxide, electrocardiogram and temperature were recorded. These parameters were recorded for every minute for first 5 min and then at 3 min intervals.

In both groups, induction was done with of injection Propofol 2 mg/kg. Body weight (BW) and injection vecuronium 0.1 mg/kg. BW endotracheal intubation done after 3 min of intermittent positive pressure ventilation with 100% oxygen. During maintenance, in both groups anesthetic concentrations were so adjusted as to maintain hemodynamic parameters (mean arterial pressure [MAP] and HR) within 15% of baseline values to ensure adequate depth of surgical anesthesia. In addition, 25-100 μg of fentanyl given to those patients who were not able to maintain MAP and HR within desired limits. In Group 1 (Propofol-group), after induction patients were maintained on N2O/O2 (60/40%) and propofol infusion @75-125 μg/kg/min. In Group 2 (sevoflurane-group), patients were maintained on N2O/O2 (60/40%) and sevoflurane 1-2%. At the end of surgery, propofol and sevoflurane were discontinued and every patient received injection ketorolac 30 mg IV as analgesic along with adequate infiltration of surgical incision with local anesthetics. The residual neuromuscular blocked was reversed with injection neostigmine 0.05 mg/kg IV and injection glycopyrrolate 0.008 mg/kg IV. After adequate motor recovery and spontaneous breathing efforts, trachea was extubated after proper oropharyngeal suctioning.

All the observations were recorded by a separate coworker who was blinded to the agent used in maintenance of general anesthesia (introduced at the end of surgery). In all patients, syringe loaded on infusion pump along with its tubing was disguised with a paper wrap and was connected to triway of the IV cannula. Hence, this coworker who took all the observations was unaware of the agent used in the maintenance phase. Duration of surgery, duration of anesthesia, time of eye opening (defined as time from discontinuation of anesthetic to the eye opening on verbal command), time of response to follow motor command (defined as time from discontinuation of anesthetics to hand squeezing), time of extubation (defined as time from discontinuation of anesthetics to extubation of endotracheal tube) and Frequency of PONV and headache were recorded for first 6 h. Of importance, patient satisfaction with anesthesia was compared after surgery in both groups. Antiemetic were given to those patients who vomited or having persistent moderate to severe nausea in that period.

For statistical analysis, categorical data analyzed with Chi-square or Fisher's extract test and continuous data assessed by t-test (unpaired). Data are presented as mean values ± standard deviation (SD) or percentages. P < 0.05 was considered to be significant.

RESULTS

The two study groups were comparable with respect to the number of participants, age, weight, gender, ASA physical status, duration of surgery and duration of anesthesia [Table 1].

Table 1

Demographic profile

Duration maintenance of anesthesia in the both groups, total dose (as mean) of fentanyl used including both pre-induction and intraoperative dosages to maintain MAP within limits, were also comparable (P = 0.62). In Group S, it was 133.5 μg (SD: 42.3) and in Group P 139.2 μg (SD: 46.9).

Toward the end of procedures, the recovery profiles of patients in both groups as recorded in terms of-time of eye opening, obeying simple verbal command (hand squeezing) and extubation time is shown in Table 2.

Table 2

Recovery timings from discontinuation of maintenance anesthetic

In both groups, the average time for all three immediate recovery landmarks were comparable (P > 0.05) after completion of the surgical procedure. Although the mean time was insignificantly shorter in the propofol group, but the subsequent recovery after eye opening was insignificantly faster in sevoflurane group. The mean duration between eye opening and to follow simple verbal command was 1.7 min in sevoflurane group and 1.8 min for propofol group while the time gap between eye opening and extubation in sevoflurane group was 3.2 min and 3.4 min for propofol group.

The occurrence of PONV in early post-operative period (first 6 h) was significantly lower in propofol group. The incidences of headache were similar in both groups. Similarly, degree of satisfaction of the surgeon with anesthesia in both groups was comparable [Table 3].

Table 3

PONV profile with an anesthesia satisfaction score

DISCUSSION

Both sevoflurane and propofol have smooth and rapid onset of action. Both can be used for induction and maintenance of general anesthesia with highly satisfying anesthetic conditions. So both propofol[12345] and sevoflurane[6789] are very popular for day care surgery due to their short recovery period. In this clinical trial, we have used hemodynamic response to pain during anesthesia as clinical assessment of anesthetic depth as used in prior many studies.[10111213] To know the depth of anesthesia is always desirable. In many recent studies, electroencephalography based modalities like bispectral index (BIS)[1415] has been used as a guide to anesthetic depth. By using such modalities, a large number of patients can be “fast-traced.” In our study, no patient in either of the group complained intraoperative awareness when they were asked for the same by the end of early recovery phase (first 6 h after the procedure).

The emergence times from discontinuation of the primary maintenance anesthesia to spontaneous eye opening, response to simple verbal command and extubation of trachea were comparable in both groups. Larsen et al.[13] found propofol group had better early recovery profile with better cognitive function in intermediate recovery phase as compared to sevoflurane group. As found in our study many other studies[1116] had found no significant difference in early recovery profile between these two agents. Although some previous studies[71718192021] comparing these two agents claimed a faster rate of emergence in sevoflurane group.

An obvious limitation in our study of measuring recovery is the equivalent depth of anesthesia in both groups. Unfortunately, there is no minimum alveolar concentration (MAC)-equivalent for IV drugs (Propofol) and there is also no reliable “depth of anesthesia” monitor.

As even BIS or other monitoring device of anesthetic depth was not available, we had to rely on standard clinical indicator to titrate the maintenance anesthetics as mentioned in methods.

PONV still remain the major complaint that affects patient overall satisfaction after anesthesia.[22] It also increase the overall cost of treatment as it often prolongs the hospital stay. There are many studies[23242526] that support our finding of significant reduction in incidence of PONV in propofol group as compared to inhalational group. The lower incidence of PONV in propofol group may be related to its “intrinsic” antiemetic[27] properties. Another explanation may be that sevoflurane causes frequent PONV.

CONCLUSION

Our study showed that emergence times in propofol and sevoflurane groups were comparable, but there was a significantly lower incidence of PONV in propofol group in early recovery phase. Thus, propofol appears to be a good alternative to sevoflurane for maintaining general anesthesia for surgeries like open cholecystectomy.