Comparison of hemodynamic stability and recovery profile with sevoflurane as inhalational agent versus propofol as total intravenous anesthesia during laparoscopic surgeries

Jigna Shah¹, Niraj Varma²¹Assistant Professor; ²DNB fellow
Department of Anesthesiology, GMERS Medical College, 225, Sola Rd, Shenbhai Nagar, Sola, Ahmedabad, Gujarat 380081, (India)

Correspondence: Dr Jigna Shah, 2-Friends Avenue, Sindhubhavanmarg, Thaltej, Ahmedabad,. Gujarat 380059. (India); E-mail:drjignars@yahoo.co.in

ABSTRACT

Background and Aim: An ideal day care anesthetic agent should have rapid smooth induction, hemodynamic stability and provide rapid recovery with minimal intra-operative and post-operative side effects. Both propofol and sevoflurane meet these criteria. The present study investigated the hemodynamic stability and recovery profile while maintaining anesthesia with sevoflurane as inhalational agent versus propofol as total intravenous anesthesia during laparoscopic surgeries.
Methodology: This was a prospective study conducted for one year at our hospital. Using convenient sampling technique, a total of 50 adult patients of American Society of Anesthesiologists (ASA) physical status I or II, aged between 18-60 years, of either sex, who were scheduled for elective day care surgeries of less than 2-hour duration under general anesthesia were selected for the study after informed consent. All the patients were randomly allocated into one of the two groups using computer generated random number table. Group-S received induction with propofol and maintenance with sevoflurane, while Group-P was induced and maintained with propofol only. Hemodynamic and recovery profile were then compared.
Data were expressed as percentages and proportions or mean and standard deviation. The differences between two groups were analysed using unpaired t-test while categorical variables were analysed using chi-square test. All the statistical tests were performed in Epi Info 3.5.1 software by CDC, USA.⁶p < 0.05 was considered as statistically significant while p < 0.01 was considered as statistically highly significant.
Results: The baseline demographic analysis showed that the two groups did not differ significantly in age, weight, sex, ASA grade and operative times. During the course of surgery, heart rate was significantly low in Group-P at 45 to 60 min than in Group-S. Systolic and diastolic blood pressure were significantly low during maintenance of anesthesia with propofol as compared to sevoflurane. Group-S showed significantly shorter time for spontaneous eye opening and recalling names and recognizing surroundings. Post-operative nausea and vomiting was significantly low in Group-P.
Conclusion: The present study concludes that patients in both groups were hemodynamically stable. Sevoflurane has the added advantage of providing rapid emergence and recovery of cognitive function. Hence it can be considered as a useful alternative to propofol for maintenance of anesthesia.
Keywords: Anesthesia; Day care surgery; Laparoscopic surgery; Propofol; Sevoflurane
Citation: Shah J, Varma N. Comparison of hemodynamic stability and recovery profile with sevoflurane as inhalational agent versus propofol as total intravenous anesthesia during laparoscopic surgeries. Anaesth Pain & Intensive Care 2018;22(2):212-218
Received – 7 Jun 2017, Reviewed – 13, 18 Jun, 18 Dec 2018, Corrected – 11, 17 Jul 2018, Accepted 18 Jul 2018

INTRODUCTION

Daycare surgery is a planned surgery wherein the patients, requiring early recovery and discharge, are admitted for short stay for surgery on a non-resident basis.¹ It is one of the most common surgical procedures performed worldwide and widely used nowadays for laparoscopic appendectomy, lap cholecystectomy, lap hernioplasty, other urology surgeries and gynaecological surgeries like diagnostic laparoscopy for infertility, hysteroscopy, embryo transfer etc. Current practices for establishing an anesthetic state consists of initial administration of an intravenous sedative-hypnotic as an induction agent followed by inhalational agents for maintenance of anesthesia. However, one common problem encountered during such practice is the phase of transition from the induction to maintenance. This has promoted the rediscovery of single agent anesthesia, which avoids problems associated with transition phase.

An ideal day-care anesthetic agent should have rapid smooth induction and provide rapid recovery with minimal intra-operative and post-operative side effects.²These are the characteristics desirable for early hospital discharge. It is nearly improbable that a single anesthetic agent completely satisfies all these requirements, however pharmacological developments over the past decades have brought us considerably closer.

By virtue of its kinetic properties, propofol has become the preferred intravenous (IV) anesthetic agent for day-care surgeries.³Propofol allows for rapid induction of anesthesia, adequate maintenance and rapid recovery with minimal post-operative nausea vomiting (PONV). Sevoflurane, a newer volatile halogenated inhalational anesthetic agent with relatively low blood solubility also provides both rapid induction and recovery time.⁴ The non-pungent odor of the drug makes it agreeable for most patients especially during an inhalational induction of anesthesia. Sevoflurane has been successfully used as an alternative to propofol in various daycare procedures.⁵

As the recovery characteristics of propofol are comparable with many newer inhalational agents, we conducted a study to determine if sevoflurane offered advantages in terms of hemodynamic stability, recovery profile and emergence times as compared to conventional intravenous propofol induced anesthesia.

METHODOLOGY

This study was conducted in department of Anesthesiology within the premises of Sterling Hospital, Ahmedabad from January 2011 till December 2011. This was a prospective study designed to compare the hemodynamic and recovery profile of patients administered with propofol versus sevoflurane for general anesthesia. Appropriate ethical clearance was obtained from Hospital Ethics Committee. Each patient was included in the study only after informed consent.

Using convenient sampling technique, a total of 50 adult patients of American Society of Anesthesiologists (ASA) physical status I or II, aged between 18-60 y, of either sex, who were scheduled for elective day care laparoscopic surgeries of less than 2-h duration under general anesthesia were selected for the study after informed consent. Patients who provided consent to be included in the study or patients with correlated cardiovascular, pulmonary, renal disease or history of hypersensitivity to halogenated anesthetic agents were excluded from the study. All the patients were randomly allocated into one of the two groups using computer generated random number table. Hence each group contained a total of 25 patients.

Pre anesthetic checkup was performed the day before and on the day of surgery. Basic routine investigations like hemoglobin, renal function tests, serum electrolytes, random blood sugar, electrocardiogram (ECG) and chest x-ray PA view were done and recorded. In the operating room, all standard monitors like non-invasive blood pressure (NIBP), pulse-oximetry (SpO₂), electrocardiogram (ECG) and capnography (EtCO₂) were attached and vital parameters of the patient recorded. All the patients in both groups were pre-medicated with inj glycopyrrolate 4 µg/kg iv, inj fentanyl 1 µg/kg iv and inj lidocaine 1.5 mg/kg iv. In both groups, after pre-oxygenation with 100% O₂ for three min, anesthesia was induced using inj propofol 2 mg/kg iv. This was followed by endotracheal intubation facilitated using inj succinylcholine 2 mg/kg iv. Intubation was confirmed with EtCO₂ and inj vecuronium 0.05 mg/kg iv was given after return of respiration. In both groups patients were put on Circle absorber system (ventilator) with IPPV mode with tidal volume 7 ml/kg, respiratory rate 16/min with PEEP 5 cmH₂O. In Both groups intra operative non-opioid analgesia was given in the form of inj diclofenac and inj paracetamol to all the patients.

In Group-S, anesthesia was maintained using sevoflurane (1-2%) dial concentration, nitrous oxide (50%) and oxygen (50%) with intermittent injection of vecuronium. In Group-P, anesthesia was maintained with propofol (100-120 µg/kg/min), nitrous oxide (50%) and oxygen (50%) with injection of vecuronium intermittently.

At the end of the surgery, in both groups sevoflurane and propofol were discontinued, especially when deflation of pneumoperitoneum and closure started and onset of spontaneous respiration also. Neuromuscular blockade was reversed with inj neostigmine 50 µg/kg iv and inj glycopyrrolate 8 µg/kg iv. Extubation of trachea was done when patients were adequately recovered from the effects of neuromuscular blockade with regular breathing pattern and were able to respond to verbal commands. Time of extubation and the times at which patients were able to state their name were recorded.

The heart rate, non-invasive blood pressure, oxygen saturation (SpO₂) and end tidal CO₂ (EtCO₂) were recorded pre-operatively, every minute from induction and intubation for 5 min, at 15 min intervals during surgery and after extubation at 5, 10, 15 and 30 min. Emergence was assessed at 15 sec intervals after discontinuation of the volatile anesthetic. Times since discontinuation of anesthetic agent were recorded. The time at which the patients opened their eyes and responded to verbal command were recorded. Anesthesia time and operative time were also recorded. Postoperative follow up for complications like nausea, vomiting and general discomfort was done for 24 h.

Data analysis: Qualitative data were expressed as percentages and proportions. Quantitative data were expressed as mean and standard deviation. The differences between two groups with respect to continuous variables were analysed using unpaired t-test while categorical variables were analysed using chi-square test. All the statistical tests were performed in Epi Info 3.5.1 software by CDC, USA.⁶p < 0.05 was considered as statistically significant while p < 0.01 was considered as statistically highly significant.

RESULTS

A total of 50 patients aged 18-60 years belonging to ASA grade I-II were included in the study in two equal random groups. The baseline demographic analysis showed that the two groups did not differ significantly in age, weight and sex. Both the groups were comparable with respect to ASA grade and operative time (the difference was non-significant) (Table 1).

Table 1: Baseline characteristics of the patients

Characteristic		Group-S N=25	Group-P N=25	p value	Inference*
Age (Mean ± SD) (y)		41.1 ± 12.2	38.1 ± 12.7	0.39	NS
Weight (Mean ± SD) (kg)		52.9 ± 13.9	58.4 ± 14.1	0.55	NS
Sex	Male	9	12	0.38	NS
Sex	Female	16	13	0.38	NS
ASA grade	Grade I	10	10	1.0	NS
ASA grade	Grade II	20	20	1.0	NS
Operative time (min)		72.0 ± 15.4	75.6 ± 16.0	0.49	NS

*NS = non-significant

There was no significant difference in heart rate between the two groups during intra-operative intervals, except at 45 and 60 min. Post-operatively, the heart rate was significantly higher in Group-S at 5, 10 and 15 min intervals (Table 2).

Table 2: Mean heart rate (beats per min) with standard deviation at various intervals

Time (in min)	Group-S N=25	Group-P N=25	P value	Inference*
Pre-op baseline	73.2 ± 2.9	75.2 ± 3.5	0.07	NS
Intubation	78.6 ± 4.8	80.5 ± 4.1	0.13	NS
Post-intubation 5 m	76.1 ± 1.3	75.3 ± 4.0	0.11	NS
Insufflation 10 m	83.8 ± 4.9	81.9 ± 2.5	0.09	NS
15 m	73.4 ± 3.9	72.3 ± 3.7	0.12	NS
30 m	69.4 ± 2.5	69.5 ± 3.4	0.18	NS
45 m	72.0 ± 3.5	67.0 ± 3.3	0.02	S
60 m	72.2 ± 5.4	65.8 ± 3.8	0.01	S
75 m	69.7 ± 4.3	67.0 ± 3.7	0.15	NS
90 m	68.8 ± 3.8	67.1 ± 2.7	0.11	NS
105 m	67.8 ± 3.5	68.0 ± 2.4	0.21	NS
120 m/END	71.6 ± 3.2	68.7 ± 3.5	0.20	NS
Post-op 5 m	89.6 ± 7.9	82.8 ± 5.4	0.01	S
Post-op 10 m	87.2 ± 6.3	83.4 ± 5.0	0.01	S
Post-op 15 m	86.0 ± 5.3	82.8 ± 5.4	0.02	S
Post-op 30 m	84.24 ± 5.79	80.72 ± 5.47	0.16	NS

*S = significant, NS = non-significant

Table 3: Mean systolic and diastolic non-invasive blood pressure (mmHg) at various intervals

Time (in min)	Systolic blood pressure		p	Diastolic blood pressure		p
Time (in min)	Group-S N=25	Group-P N=25	p	Group-S N=25	Group-P N=25	p
Pre-op baseline	125.6 ± 8.4	123.2 ± 8.5	0.11	72.0 ± 5.4	71.3 ± 7.0	0.12
Intubation	137.6 ± 12.1	146.3 ± 15.4	0.06	78.2 ± 7.2	77.0 ± 8.1	0.22
Post-intubation 5 m	107.8 ± 7.7	106.4 ± 13.6	0.12	68.9 ± 5.2	60.4 ± 4.9	0.06
Insufflation 10 m	142.3 ± 8.0	138.1 ± 8.0	0.06	80.3 ± 5.1	73.6 ± 6.5	0.01
15 m	134.6 ± 5.8	126.8 ± 7.7	0.01	78.9 ± 4.6	71.0 ± 4.6	0.01
30 m	135.0 ± 14.0	121.1 ± 6.9	0.02	78.3 ± 4.2	71.6 ± 3.9	0.02
45 m	133.4 ± 14.1	113.4 ± 9.3	0.01	76.8 ± 4.4	68.5 ± 4.4	0.00
60 m	130.0 ± 5.4	109.3 ± 7.2	0.03	75.3 ± 4.3	67.5 ± 4.4	0.01
75 m	130.5 ± 4.9	116.2 ± 8.9	0.01	78.5 ± 4.9	64.8 ± 3.6	0.00
90 m	132.0 ± 3.5	115.0 ± 6.8	0.01	78.3 ± 2.6	65.6 ± 4.2	0.00
105 m	133.6 ± 4.3	113.0 ± 6.7	0.00	78.4 ± 4.7	65.3 ± 1.6	0.01
120 m/END	131.0 ± 4.2	116.0 ± 5.3	0.01	85.0 ± 1.4	64.0 ± 4.0	0.00
Post-op 5 m	143.4 ± 6.5	150.2 ± 6.6	0.23	87.0 ± 5.0	87.2 ± 5.9	1.10
Post-op 10 m	134.3 ± 4.3	134.0 ± 6.3	1.01	81.1 ± 5.8	78.2 ± 6.9	0.11
Post-op 15 m	130.5 ± 3.9	129.8 ± 6.8	0.25	78.8 ± 4.8	77.7 ± 4.6	0.19
Post-op 30 m	127.1 ± 4.3	121.9 ± 13.3	0.06	77.2 ± 4.2	78.3 ± 5.9	0.16

The systolic blood pressure was significantly low in Group-P from 15 min after insufflations till the end of surgery. Similarly, the diastolic blood pressure was significantly low in Group-P from 10 min of insufflation till the end of surgery. There was no significant difference in systolic and diastolic blood pressure between the two groups during induction as well as post-operatively (Table 3).

The end tidal CO₂ levels between the two groups did not differ significantly during induction and intubation. However, the EtCO₂ was significantly higher in Group-S from 10 min of insufflations till 60 min (Table 4).

Table 4: Mean end tidal CO₂ (EtCO₂) (mmHg) levels at various intervals

Time (in min)	Group-S N=25	Group-P N=25	p value	Inference*
Intubation	32.7 ± 1.3	33.3 ± 1.8	0.18	NS
Post-intubation 5 m	28.9 ± 1.0	30.3 ± 1.4	0.27	NS
Insufflation 10 m	37.7 ± 1.7	33.4 ± 2.0	0.01	S
15 m	35.4 ± 1.6	32.9 ± 1.5	0.03	S
30 m	34.2 ± 1.6	32.1 ± 1.5	0.02	S
45 m	34.8 ± 2.0	32.0 ± 1.7	0.01	S
60 m	33.6 ± 1.6	30.5 ± 1.5	0.01	S
75 m	31.4 ± 1.1	30.8 ± 2.9	0.22	NS
90 m	31.0 ± 1.2	30.2 ± 2.8	0.13	NS
105 m	30.8 ± 1.0	30.0 ± 3.3	0.06	NS
120 m/ END	30.0 ± 1.4	28.5 ± 4.9	0.02	S

*S = significant, NS = non=significant

Table 5: Recovery characteristics and post-operative complication in both groups

Profile

Group-S

N=25

Group-P

N=25

P value

Inference*

Recovery profile (emergence)

Open eyes (Mean ± SD) (min)

Orientation (Mean ± SD) (min)

Seat (Mean ± SD) (h)

Walk (Mean ± SD) (h)

3.4 ± 1.2

5.8 ± 1.5

3.6 ± 1.1

6.4 ± 1.4

8.0 ± 0.7

11.4 ± 0.1

3.4 ± 0.7

6.7 ± 0.8

0.00

0.15

0.09

Complications

PONV (0-4 hours) (N)

PONV (4-48 hours) (N)

Pain VAS (Mean ± SD)

4.5 ± 0.6

4.8 ± 0.6

0.00

0.11

*S = significant, NS = non-significant

Propofol group showed significant delay in spontaneous eye opening compared to sevoflurane group. Propofol also showed significant delay in recalling name and recognizing surroundings compared to sevoflurane group (Table 5). But the time to seat upright and walk without support, shows no significant difference in both groups. Post-operative nausea and vomiting was significantly low in group II, while no significant different was found in visual analog scale of pain between the two groups (Table 5).

DISCUSSION

Laparoscopic procedures are rapidly increasing nowadays in day care procedures because of reduced hospital stay and health cost.⁷ Rapid emergence and post-operative recovery as well as hemodynamic stability are important requisites of modern day anesthesia.⁸Generally both propofol and sevoflurane meet these criteria. Propofol is preferred intravenous agent in day care surgeries as it has smooth induction and rapid recovery with some antiemetic properties.⁹Sevoflurane is nowadays widely used in anesthesia because of its relative lack of airway irritation and myocardial depressant effect.¹⁰Sevoflurane has a low blood gas partition coefficient of 0.69 which contributes to rapid induction and emergence than with other volatile agents.¹¹

The present study investigated the hemodynamic and recovery profile of propofol versus sevoflurane in day care surgeries. In our study, the mean age was 41.1 years and mean weight 52.9 kgs. In a similar study conducted by Sahu DK et al.¹ the mean age was 40.9 years and mean weight 57.1 kg. Shah A et al.¹² reported in their study that mean age of the ASA grade I-II patients was 35.5 years while mean weight was 52.8 kg. The mean age and weight in a study conducted by Singh SK et al.³ was 38.7 years and 56.6 kg respectively. Thus there was no wide variation in mean age and weight across different studies.

Reduction in pulse rate was noticed in both the groups post induction as patients were induced with propofol. During the course of surgery, heart rate was significantly low in Group-P at 45 to 60 min than in Group-S. This could be due to maintenance of anesthesia in Group-P with propofol. Juckenhöfel S, et al.¹³and Yao XH¹⁴ et al. observed a significant decrease in mean heart rate during maintenance of anesthesia with propofol but not with sevoflurane.

In present study, systolic and diastolic blood pressures were significantly low during maintenance of anesthesia with propofol as compared to sevoflurane. Similar findings were reported by several studies conducted by Orhon ZNet al.¹⁵, Joo HS et al.¹⁶, Shah A et al.¹², where blood pressure significantly decreased intra-operatively with propofol group, although patients remained hemodynamically stable. Samantaray A et al.¹⁷observed that the intra operative haemodynamic parameters like heart rate and blood pressure were within acceptable range in both the groups during his study on spine surgery. Frink et al.,¹⁸ found that compared to baseline values, sevoflurane anesthesia decreased systolic and diastolic arterial blood pressures 3-5 min before surgical incision.

The patients in our study belonging to sevoflurane group showed significantly shorter time for spontaneous eye opening and recalling names and recognizing surroundings, as compared to propofol group. Similar findings were reported by Wandel C et al.¹⁹ Our findings also concurred with studies done by Yao XH et al.¹⁴ and Singh SK³which reported emergence and recovery were significantly faster in sevoflurane group than propofol group. Contrary to our findings, Gupta et al.²⁰ reported no significant difference in eye opening time between the sevoflurane and propofol group whereas Larsen et al.²¹ reported better recovery characteristics in propofol group.

Post-operative nausea vomiting still affects the level of content of patients after anesthesia. Out study reported significantly low PONV in propofol group. This could be due the intrinsic anti-emetic properties of propofol. Many studies^22-26 reported similar findings.

CONCLUSION

The present study concludes that patients in both group were hemodynamically stable, though there were slight variations in heart rate, blood pressure and EtCO2 in both groups. Sevoflurane has the added advantage of providing rapid emergence and recovery of cognitive function. Hence it can be considered as a useful alternative to propofol for maintenance of anesthesia. However, it is advisable to administer anti-emetic prophylaxis when sevoflurane is to be used to maintain anesthesia.

Source of funding: None
Conflict of interest: None
Authors’ contribution:
JS: Concept, study design, manuscript writing
NV: Data collection and analysis, study conduction

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