468 Original Article
Comparative Evaluation of Intrathecal Bupivacaine Alone, Bupivacaine-fentanyl, and Bupivacainedexmedetomidine in Caesarean Section
Authors
Y. Sun1, Y. Xu2, G.-N. Wang2
Affiliations
1
Key words ▶ bupivacaine ● ▶ fentanyl ● ▶ dexmedetomidine ● ▶ post-operative analgesia ● ▶ cesarean section ● ▶ sensory block ● ▶ motor block ●
Abstract
Bibliography DOI http://dx.doi.org/ 10.1055/s-0034-1387740 Published online: September 10, 2014 Drug Res 2015; 65: 468–472 © Georg Thieme Verlag KG Stuttgart · New York ISSN 2194-9379 Correspondence G.-N. Wang Department of Anesthesia The Third Affiliated Hospital of Harbin Medical University No. 150 Haping Road Nangang District Harbin Heilongjiang 150000 China Tel.: + 86/451/86298 811 Fax: + 86/451/86298 811 [email protected]
Department of Anesthesia, Heilongjiang Province Hospital, Harbin, Heilongjiang Province, China Department of Anesthesia, The Third Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang Province, China
▼
Purpose: In this study, we aimed to compare the effects of bupivacaine alone, bupivacaine plus fentanyl, and bupivacaine plus dexmedetomidine for postoperative analgesia in women undergoing cesarean section under spinal anesthesia. Material and methods: 90 term parturients scheduled to have elective cesarean section and ASA physical status I or II were allocated randomly into 3 groups to receive either bupivacaine (Bv group) or bupivacaine plus fentanyl (BvF group) or bupivacaine plus dexmedetomidine (BvD group). The onset time of sensory block, maximum sensory block level, duration of motor and sensory block, onset of post-operative pain, sedation scores, Apgar scores and side
Introduction
▼
Spinal anesthesia has evolved as one the preferred and widely used technique for urgent and emergency situations such as cesarean section [1]. Apart from being economical and easy to administer, spinal anesthesia provides both analgesia and muscular relaxation with rapid onset of action [2, 3]. In addition, spinal anesthesia is reliable in producing uniform sensory and motor blockade as compared to epidural anesthesia [4– 6].The main disadvantage in spinal anesthesia is lack of long lasting postoperative analgesia [7]. Although, bupivacaine is a long acting local anesthetic with high-potency and differential sensorial-motor blockage however, it doesn’t have advantage of prolonged postoperative analgesia. Therefore, it is a continuous challenge for the anesthesiologists to achieve a subarachnoid block that provides high quality postoperative analgesia of consistently prolonged duration.
Sun Y et al. Adjuvants to Bupivacaine … Drug Res 2015; 65: 468–472
effects were recorded and statistically compared across 3 groups. Results: Regression time to T10 was significantly longer in BvD group, sensory block was also prolonged in BvD group without any difference in duration of motor block. Onset of post-operative pain was delayed in BvD group. Sedation scores (VAS) were improved in case of BvD with least values of 0–3 followed by BvF (1–4). There was no significant difference in Apgar scores and neonatal arterial gas pressures across 3 groups. Conclusion: The use of dexmedtomidine as an adjuvant to bupivacaine in cesarean surgeries provides better intra-operative and post-operative analgesia without having significant impact on Apgar scores or incidence of side effects.
Over the years, many drugs have been used intrathecally as an adjuvants to local anesthetic to prolong the intraoperative as well as postoperative analgesia with variable effects [8]. The cesarean section cases under spinal anesthesia are mostly associated with visceral pain, nausea, and vomiting is common problem under spinal anesthesia [9]. Effective postoperative analgesia can be achieved with systemic administration of opioids and/or non-opioid analgesics with spinal anesthesia. However, addition of opioids to local anesthetic solution have disadvantages, such as pruritus nausea, vomiting, urinary retention and respiratory depression [10]. The adjuvants most commonly used in combination with bupivacaine are opioids and clonidine. The addition of opioid fentanyl to hyperbaric bupivacaine improves the quality of intraoperative and early postoperative subarachnoid block. Dexmedetomidine, is a new and more selective α2-A receptor compared to clonidine, with
Downloaded by: Chinese University of Hong Kong. Copyrighted material.
received 16.07.2014 accepted 01.08.2014
2
higher sedative and analgesic effects. Dexmedetomidine provides stable homodynamic conditions, good sedation, and good quality of intraoperative and prolonged postoperative analgesia with minimal side effects [11–13]. The use of dexmedetomidine is under evaluation as a neuraxial adjuvant and very limited research is conducted to evaluate its effects in context of cesarean section. In this study, we studied the effects of fentanyl and dexmedetomidine added as adjuvants to bupivacaine and compared it with the plain bupivacaine for quality of block and postoperative analgesia in women undergoing cesarean section under spinal anesthesia. The primary outcome measure compared was duration of effective analgesia measured by time in minutes for requirement of rescue analgesia. Secondary outcome measures compared were onset, peak and duration of sensory and motor blockade, level of sedation, maternal hemodynamic parameters and fetal parameters.
Materials and Methods
peripheral O2 saturation (Odam Physiogards SM 785, France). All patients were given a supplementation of 3 L/minO2 by a face mask. Positioning the parturients in the left lateral or sitting position, epidural puncture was done with 16-gauge Tuohy needle at L2-L3 or L3-L4 interspace and epidural catheter was introduced in cephalic direction. All spinal blocks were performed at the level of interspace with a 25 G Whitacre needle in the sitting position and study drugs were injected at a rate of 1 mL/15 s by the same anesthesiologist. After blockade, patients were placed in the supine position and a Crawford wedge was used to displace the uterus to the left until birth. In cases where sensory block did not reached T6 within 20 min after the injection, a general anesthetic was administered. Sensory block was evaluated every 2 min with a pinprick test; motor block was evaluated with the Bromage scale (0 = no motor loss, 1 = inability to flex the hip, 2 = inability to flex the knee, and 3 = inability to flex the ankle). Onset times for sensory and motor blocks were recorded. Surgical intervention was initiated when block reached the T5 level.
Selection of subjects
Block evaluations
▼
The study was conducted after approval from hospital ethics committee and a written informed consent from study subjects. After satisfying inclusion and exclusion criteria a double blind controlled, randomized study enrolled 90 parturient with singleton pregnancy, American Society of Anesthesiologists (ASA) I and II scheduled for elective and aged between 20 and 35 years. The exclusion criteria were preeclampsia, ASA III–IV, prematurity, multiple gestation, and contraindications to spinal block, history of hypersensitivity and anaphylactic reactions, pregnancy terms other than 36–40 weeks. A randomized allocation of subjects into 3 groups (30 in each group) was done using SAS 9.1 software. The 3 groups were scheduled to receive drugs as per the study design as follows: I. Bupivacaine (Bv): patients were given 10 mg (2 mL) of hyperbaric bupivacaine 0.5 %, plus 1.0 mL of normal saline. II. Bupivacaine + fentanvl group: (BvF): patients were given 10 mg (2 mL) of hyperbaric bupivacaine 0.5 %, plus 25 µg fentanyl in 1.0 mL of normal saline. III. Bupivacaine + dexmedetomidine group (BvD): patients were given 10 mg (2 mL) of hyperbaric bupivacaine 0.5 %, plus 10 µg dexmedetomidine in 1.0 mL of normal saline. Saline 0.9 % was added to all groups to obtain a total volume of 3 mL hence ensuring equal volume of anesthetic is used. The drugs used were commercial products and selected without batch determination.
Anesthetic management
All syringes were identical and prepared according to randomization by an anesthesiologist who was not involved in any other aspect of the study. The investigator who prepared the drug, the anesthesiologist who administered the injections and the patients, were unaware of the group allocated and the drug that was received by the patient. Block characteristics assessments were performed by an anesthesiologist blinded to patient allocations and study drugs. No premedication was administered to any of the patients. Before anesthesia induction, IV access was obtained and 10 mL/kg Ringer’s lactate solution was infused. Intra operative monitoring of vital signs was done and the following parameters were recorded as a baseline value for hemodynamic measurements: non-invasive pressure, heart rate, and
Respiratory and hemodynamic parameters of parturient were evaluated which included: mean blood pressure (MBP; mm Hg), heart rate (HR; bpm), respiratory rate (rpm), and oxygen saturation (SpO2). The time points at which these parameters were evaluated were: before blockade (M0), immediately after blockade (M1), every 5 min during procedure (M2), at the end of procedure every 30 min until 180 min (M3). If SBP values decreased 20 % with respect to the baseline values, or decreased to 100 mm Hg, fluid loading and ephedrine (5 mg) were administered. A decrease in heart rate to 55 beats/min was considered bradycardia and atropine (0.5 mg) was administered. Motor block levels were evaluated 20 min after anaesthetic solution injection using Modified Bromage Scale (MBS) (0 = No block, 1 = inability to flex the hip, 2 = ability to flex feet only, 3 = complete immobility of lower limbs): levels were recorded every 3 min for the first 18 min after epidural local anaesthetic injection and every 30 min until minute 180 in the postoperative stage. Sensory block latency which is the time elapsed between the end of anaesthetic solution injection into the subarachnoid space (assessed every minute) and onset time of sensory block at the T10 level, the highest level of sensory block, duration of sensory block. Motor block onset time was defined and noted as the time between epidural injection to MBS 1, and total motor block duration was defined and noted as the time between motor block onset to MBS = 0. Sedation scores were recorded using visual analog scale (VAS) (0 = no pain and 10 = worst pain possible) before the initiation of surgery and thereafter every 15 min during the surgical procedure. Apgar scores were evaluated at first and fifth minutes by a paediatrician who was blinded to the study. For blood gas measurements, samples were obtained from the umbilical cord of new-borns. Intraoperative and postoperative nausea, vomiting, pruritus, respiratory depression, and other side effects were recorded at the first, second, sixth, and 12th hours.
Statistical analysis
Statistical analysis was performed using SPSS (Version 20.0 IBMSPSS Inc., Armonk, New York). Fisher’s exact test was used for analysis of the degree of motor block, sensory block level, maternal side effects, and level of consciousness. A χ2 test was used to Sun Y et al. Adjuvants to Bupivacaine … Drug Res 2015; 65: 468–472
Downloaded by: Chinese University of Hong Kong. Copyrighted material.
Original Article 469
470 Original Article
Time of onset of sensory block, min Highest sensory block level Time to highest sensory block level, min Time of onset of motor block, min Regression time to T10, min Duration of sensory block, min Time for complete motor recovery, min Onset of postoperative pain, min
Group BvF
Group BvD
(n = 30)
(n = 30)
(n = 30)
P
29.75 (4.90) 165.23 (5.80) 73.85 (8.57) 38.55 (0.77) 21/4 74.6 ± 6.5 42.89 (9.25)
30.55 (5.05) 163.47 (5.10) 75.23 (9.21) 38.38 (0.59) 20/5 75.2 ± 7.1 43.2 (8.6)
28.56 (4.73) 164.58 (4.65) 74.65 (8.85) 38.27 (0.61) 19/6 75.3 ± 7.3 43.11 (8.70)
0.47 0.12 0.23 0.87 0.69 0.61 0.81
Group Bv
Group BvF
Group BvD
P
7.8 T4 42 % 9.1 (3.52) 7.6 (2.20) 102.20 (16.15) 155.26 (23.09) 127.5 (25.71) 220.55 (28.64)
7.6 T4 40 % 8.47 (2.18) 7.4 (2.80) 117.71 (21.36) 179.0 (38.83)# 130.65 (29.87) 265.72 (25.16)
7.1 T4 44 % 8.10 (3.55)† 7.1 (2.25) 152.9 (39.62) 211.73 (51.88) 128.55 (28.90) 352.45 (26.17)
0.65 0.27 0.041† 0.22 0.003 * 0.0025 * 0.81 0.001 *
Table 1 Demographic and surgical characteristics.
Table 2 Spinal Block characteristics.
† Statistically significant difference between group Bv and BvD *Statistically significant across 3 groups # Statistically significant difference between Bv and BvF group
compare data that denotes frequency, such as gender and ASA risk category. ANOVA was used to compare hemodynamic characteristics. A P-value of 0.05 was considered statistically significant for all comparisons.
Results
▼
The intergroup demographic profiles of the patients in all the 3 groups were comparable with regard to age, weight and height. The distribution as per ASA status was similar in the 3 groups and mean duration of surgery was comparable (P > 0.05). There was no significant statistical difference between the gestational age, mean arterial pressure (baseline) and duration of surgery ▶ Table 1). among any of the groups ( ● The spinal block characteristics are presented in ● ▶ Table 2. The results indicated that there was statistical difference in regression time to T10 between the 3 groups {P ( = 0.003);
Comparative Evaluation of Intrathecal Bupivacaine Alone, Bupivacaine-fentanyl, and Bupivacainedexmedetomidine in Caesarean Section
Authors
Y. Sun1, Y. Xu2, G.-N. Wang2
Affiliations
1
Key words ▶ bupivacaine ● ▶ fentanyl ● ▶ dexmedetomidine ● ▶ post-operative analgesia ● ▶ cesarean section ● ▶ sensory block ● ▶ motor block ●
Abstract
Bibliography DOI http://dx.doi.org/ 10.1055/s-0034-1387740 Published online: September 10, 2014 Drug Res 2015; 65: 468–472 © Georg Thieme Verlag KG Stuttgart · New York ISSN 2194-9379 Correspondence G.-N. Wang Department of Anesthesia The Third Affiliated Hospital of Harbin Medical University No. 150 Haping Road Nangang District Harbin Heilongjiang 150000 China Tel.: + 86/451/86298 811 Fax: + 86/451/86298 811 [email protected]
Department of Anesthesia, Heilongjiang Province Hospital, Harbin, Heilongjiang Province, China Department of Anesthesia, The Third Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang Province, China
▼
Purpose: In this study, we aimed to compare the effects of bupivacaine alone, bupivacaine plus fentanyl, and bupivacaine plus dexmedetomidine for postoperative analgesia in women undergoing cesarean section under spinal anesthesia. Material and methods: 90 term parturients scheduled to have elective cesarean section and ASA physical status I or II were allocated randomly into 3 groups to receive either bupivacaine (Bv group) or bupivacaine plus fentanyl (BvF group) or bupivacaine plus dexmedetomidine (BvD group). The onset time of sensory block, maximum sensory block level, duration of motor and sensory block, onset of post-operative pain, sedation scores, Apgar scores and side
Introduction
▼
Spinal anesthesia has evolved as one the preferred and widely used technique for urgent and emergency situations such as cesarean section [1]. Apart from being economical and easy to administer, spinal anesthesia provides both analgesia and muscular relaxation with rapid onset of action [2, 3]. In addition, spinal anesthesia is reliable in producing uniform sensory and motor blockade as compared to epidural anesthesia [4– 6].The main disadvantage in spinal anesthesia is lack of long lasting postoperative analgesia [7]. Although, bupivacaine is a long acting local anesthetic with high-potency and differential sensorial-motor blockage however, it doesn’t have advantage of prolonged postoperative analgesia. Therefore, it is a continuous challenge for the anesthesiologists to achieve a subarachnoid block that provides high quality postoperative analgesia of consistently prolonged duration.
Sun Y et al. Adjuvants to Bupivacaine … Drug Res 2015; 65: 468–472
effects were recorded and statistically compared across 3 groups. Results: Regression time to T10 was significantly longer in BvD group, sensory block was also prolonged in BvD group without any difference in duration of motor block. Onset of post-operative pain was delayed in BvD group. Sedation scores (VAS) were improved in case of BvD with least values of 0–3 followed by BvF (1–4). There was no significant difference in Apgar scores and neonatal arterial gas pressures across 3 groups. Conclusion: The use of dexmedtomidine as an adjuvant to bupivacaine in cesarean surgeries provides better intra-operative and post-operative analgesia without having significant impact on Apgar scores or incidence of side effects.
Over the years, many drugs have been used intrathecally as an adjuvants to local anesthetic to prolong the intraoperative as well as postoperative analgesia with variable effects [8]. The cesarean section cases under spinal anesthesia are mostly associated with visceral pain, nausea, and vomiting is common problem under spinal anesthesia [9]. Effective postoperative analgesia can be achieved with systemic administration of opioids and/or non-opioid analgesics with spinal anesthesia. However, addition of opioids to local anesthetic solution have disadvantages, such as pruritus nausea, vomiting, urinary retention and respiratory depression [10]. The adjuvants most commonly used in combination with bupivacaine are opioids and clonidine. The addition of opioid fentanyl to hyperbaric bupivacaine improves the quality of intraoperative and early postoperative subarachnoid block. Dexmedetomidine, is a new and more selective α2-A receptor compared to clonidine, with
Downloaded by: Chinese University of Hong Kong. Copyrighted material.
received 16.07.2014 accepted 01.08.2014
2
higher sedative and analgesic effects. Dexmedetomidine provides stable homodynamic conditions, good sedation, and good quality of intraoperative and prolonged postoperative analgesia with minimal side effects [11–13]. The use of dexmedetomidine is under evaluation as a neuraxial adjuvant and very limited research is conducted to evaluate its effects in context of cesarean section. In this study, we studied the effects of fentanyl and dexmedetomidine added as adjuvants to bupivacaine and compared it with the plain bupivacaine for quality of block and postoperative analgesia in women undergoing cesarean section under spinal anesthesia. The primary outcome measure compared was duration of effective analgesia measured by time in minutes for requirement of rescue analgesia. Secondary outcome measures compared were onset, peak and duration of sensory and motor blockade, level of sedation, maternal hemodynamic parameters and fetal parameters.
Materials and Methods
peripheral O2 saturation (Odam Physiogards SM 785, France). All patients were given a supplementation of 3 L/minO2 by a face mask. Positioning the parturients in the left lateral or sitting position, epidural puncture was done with 16-gauge Tuohy needle at L2-L3 or L3-L4 interspace and epidural catheter was introduced in cephalic direction. All spinal blocks were performed at the level of interspace with a 25 G Whitacre needle in the sitting position and study drugs were injected at a rate of 1 mL/15 s by the same anesthesiologist. After blockade, patients were placed in the supine position and a Crawford wedge was used to displace the uterus to the left until birth. In cases where sensory block did not reached T6 within 20 min after the injection, a general anesthetic was administered. Sensory block was evaluated every 2 min with a pinprick test; motor block was evaluated with the Bromage scale (0 = no motor loss, 1 = inability to flex the hip, 2 = inability to flex the knee, and 3 = inability to flex the ankle). Onset times for sensory and motor blocks were recorded. Surgical intervention was initiated when block reached the T5 level.
Selection of subjects
Block evaluations
▼
The study was conducted after approval from hospital ethics committee and a written informed consent from study subjects. After satisfying inclusion and exclusion criteria a double blind controlled, randomized study enrolled 90 parturient with singleton pregnancy, American Society of Anesthesiologists (ASA) I and II scheduled for elective and aged between 20 and 35 years. The exclusion criteria were preeclampsia, ASA III–IV, prematurity, multiple gestation, and contraindications to spinal block, history of hypersensitivity and anaphylactic reactions, pregnancy terms other than 36–40 weeks. A randomized allocation of subjects into 3 groups (30 in each group) was done using SAS 9.1 software. The 3 groups were scheduled to receive drugs as per the study design as follows: I. Bupivacaine (Bv): patients were given 10 mg (2 mL) of hyperbaric bupivacaine 0.5 %, plus 1.0 mL of normal saline. II. Bupivacaine + fentanvl group: (BvF): patients were given 10 mg (2 mL) of hyperbaric bupivacaine 0.5 %, plus 25 µg fentanyl in 1.0 mL of normal saline. III. Bupivacaine + dexmedetomidine group (BvD): patients were given 10 mg (2 mL) of hyperbaric bupivacaine 0.5 %, plus 10 µg dexmedetomidine in 1.0 mL of normal saline. Saline 0.9 % was added to all groups to obtain a total volume of 3 mL hence ensuring equal volume of anesthetic is used. The drugs used were commercial products and selected without batch determination.
Anesthetic management
All syringes were identical and prepared according to randomization by an anesthesiologist who was not involved in any other aspect of the study. The investigator who prepared the drug, the anesthesiologist who administered the injections and the patients, were unaware of the group allocated and the drug that was received by the patient. Block characteristics assessments were performed by an anesthesiologist blinded to patient allocations and study drugs. No premedication was administered to any of the patients. Before anesthesia induction, IV access was obtained and 10 mL/kg Ringer’s lactate solution was infused. Intra operative monitoring of vital signs was done and the following parameters were recorded as a baseline value for hemodynamic measurements: non-invasive pressure, heart rate, and
Respiratory and hemodynamic parameters of parturient were evaluated which included: mean blood pressure (MBP; mm Hg), heart rate (HR; bpm), respiratory rate (rpm), and oxygen saturation (SpO2). The time points at which these parameters were evaluated were: before blockade (M0), immediately after blockade (M1), every 5 min during procedure (M2), at the end of procedure every 30 min until 180 min (M3). If SBP values decreased 20 % with respect to the baseline values, or decreased to 100 mm Hg, fluid loading and ephedrine (5 mg) were administered. A decrease in heart rate to 55 beats/min was considered bradycardia and atropine (0.5 mg) was administered. Motor block levels were evaluated 20 min after anaesthetic solution injection using Modified Bromage Scale (MBS) (0 = No block, 1 = inability to flex the hip, 2 = ability to flex feet only, 3 = complete immobility of lower limbs): levels were recorded every 3 min for the first 18 min after epidural local anaesthetic injection and every 30 min until minute 180 in the postoperative stage. Sensory block latency which is the time elapsed between the end of anaesthetic solution injection into the subarachnoid space (assessed every minute) and onset time of sensory block at the T10 level, the highest level of sensory block, duration of sensory block. Motor block onset time was defined and noted as the time between epidural injection to MBS 1, and total motor block duration was defined and noted as the time between motor block onset to MBS = 0. Sedation scores were recorded using visual analog scale (VAS) (0 = no pain and 10 = worst pain possible) before the initiation of surgery and thereafter every 15 min during the surgical procedure. Apgar scores were evaluated at first and fifth minutes by a paediatrician who was blinded to the study. For blood gas measurements, samples were obtained from the umbilical cord of new-borns. Intraoperative and postoperative nausea, vomiting, pruritus, respiratory depression, and other side effects were recorded at the first, second, sixth, and 12th hours.
Statistical analysis
Statistical analysis was performed using SPSS (Version 20.0 IBMSPSS Inc., Armonk, New York). Fisher’s exact test was used for analysis of the degree of motor block, sensory block level, maternal side effects, and level of consciousness. A χ2 test was used to Sun Y et al. Adjuvants to Bupivacaine … Drug Res 2015; 65: 468–472
Downloaded by: Chinese University of Hong Kong. Copyrighted material.
Original Article 469
470 Original Article
Time of onset of sensory block, min Highest sensory block level Time to highest sensory block level, min Time of onset of motor block, min Regression time to T10, min Duration of sensory block, min Time for complete motor recovery, min Onset of postoperative pain, min
Group BvF
Group BvD
(n = 30)
(n = 30)
(n = 30)
P
29.75 (4.90) 165.23 (5.80) 73.85 (8.57) 38.55 (0.77) 21/4 74.6 ± 6.5 42.89 (9.25)
30.55 (5.05) 163.47 (5.10) 75.23 (9.21) 38.38 (0.59) 20/5 75.2 ± 7.1 43.2 (8.6)
28.56 (4.73) 164.58 (4.65) 74.65 (8.85) 38.27 (0.61) 19/6 75.3 ± 7.3 43.11 (8.70)
0.47 0.12 0.23 0.87 0.69 0.61 0.81
Group Bv
Group BvF
Group BvD
P
7.8 T4 42 % 9.1 (3.52) 7.6 (2.20) 102.20 (16.15) 155.26 (23.09) 127.5 (25.71) 220.55 (28.64)
7.6 T4 40 % 8.47 (2.18) 7.4 (2.80) 117.71 (21.36) 179.0 (38.83)# 130.65 (29.87) 265.72 (25.16)
7.1 T4 44 % 8.10 (3.55)† 7.1 (2.25) 152.9 (39.62) 211.73 (51.88) 128.55 (28.90) 352.45 (26.17)
0.65 0.27 0.041† 0.22 0.003 * 0.0025 * 0.81 0.001 *
Table 1 Demographic and surgical characteristics.
Table 2 Spinal Block characteristics.
† Statistically significant difference between group Bv and BvD *Statistically significant across 3 groups # Statistically significant difference between Bv and BvF group
compare data that denotes frequency, such as gender and ASA risk category. ANOVA was used to compare hemodynamic characteristics. A P-value of 0.05 was considered statistically significant for all comparisons.
Results
▼
The intergroup demographic profiles of the patients in all the 3 groups were comparable with regard to age, weight and height. The distribution as per ASA status was similar in the 3 groups and mean duration of surgery was comparable (P > 0.05). There was no significant statistical difference between the gestational age, mean arterial pressure (baseline) and duration of surgery ▶ Table 1). among any of the groups ( ● The spinal block characteristics are presented in ● ▶ Table 2. The results indicated that there was statistical difference in regression time to T10 between the 3 groups {P ( = 0.003);
