A randomised controlled trial of hyperbaric bupivacaine with opioids, injected as either a mixture or sequentially, for spinal anaesthesia for caesarean section

Comparison of sequential and mixture injections of opioids and hyperbaric bupivacaine for subarachnoid block for lower segment caesarean section: a randomised controlled study

INTRODUCTION

Opioids are commonly added to local anaesthetic for subarachnoid block for caesarean section due to their synergistic effects. The physiochemical characteristics of opioids suggest premixing with hyperbaric bupivacaine may limit their distribution within the CSF. We studied the effect of a separate injection with a combination of bupivacaine, morphine and fentanyl on block characteristics, haemodynamic changes, postoperative pain and patient satisfaction.

METHOD

Following ethical approval and informed consent, a prospective double-blinded randomised controlled trial was performed in a university hospital. A total of 126 patients undergoing caesarean section were randomised to two groups. In group M, the premixed group, patients received 12 mg of hyperbaric bupivacaine, 20 mcg of fentanyl and 100 mcg of morphine injected as a single mixture. In group S, the separate injection group, patients received the same drugs in separate injections. Measurements included haemodynamics, block distribution, intra- and postoperative pain, as well as patient satisfaction.

RESULTS

Patients in both groups had similar block height, time to maximum sensory block, time to block regression and motor block. However, haemodynamics were different between the groups. The proportion of systolic hypotension episodes was greater in group S [159/1320 (12.05%)] than group M [113/1452 (7.78%)], with P = 0.0002. Moreover, a greater amount of ephedrine was administered in group S than group M, with values 12.09 (8.1) and 9.09 (8.5) mg respectively (P = 0.001). Additionally, postoperative pain, as measured by the Visual Analogue Scale (VAS), was greater in group M, with a VAS of 4.6 (1.7), vs. group S, which recorded a VAS of 3.8 (2.0) (P = 0.017).

CONCLUSION

Sequential injection of intrathecal opioids and hyperbaric bupivacaine resulted in greater early haemodynamic instability and slightly better postoperative analgesia without any difference in block height or patient satisfaction.

CLINICAL TRIAL REGISTRATION

NCT04403724.

A Comparison of Subarachnoid Block Characteristics Following Co-administration of Fentanyl Premixed With Hyperbaric Bupivacaine Versus Antecedent or Succedent to Hyperbaric Bupivacaine: A Randomized Controlled Study

Background Adjuvants are often used during subarachnoid block to enhance and prolong the analgesia and decrease the adverse effects of high doses of local anesthetic agents. Intrathecal fentanyl premixed with hyperbaric bupivacaine has been used in spinal anesthesia and compared with the sequential use of these drugs in separate syringes. However, given the paucity of literature, we conducted this study where premixed antecedent and succedent administration of intrathecal fentanyl with hyperbaric bupivacaine were compared in terms of flow dynamics, block characteristics, and hemodynamic alterations. Methodology This prospective, randomized, triple-blinded comparative study was conducted among 160 patients who were randomly allocated into four groups. Group A (n = 40) (control) received 3.0 mL (15 mg) of 0.5% hyperbaric bupivacaine and 0.5 mL of normal saline via a 5.0 mL syringe. Group B (n = 40) received 3.0 mL (15 mg) of 0.5% hyperbaric bupivacaine and 0.5 mL (25 µg) of fentanyl premixed via a single 5.0 mL syringe. Group C (n = 40) received 0.5 mL (25 µg) of fentanyl via a 1.0 mL syringe followed by 3.0 mL (15 mg) of 0.5% hyperbaric bupivacaine via a 5.0 mL syringe. Group D (n = 40) received 3.0 mL (15 mg) of 0.5% hyperbaric bupivacaine via a 5.0 mL syringe followed by 0.5 mL (25 µg) of fentanyl via a 1.0 mL syringe. The onset and regression of sensory and motor blockade, hemodynamic parameters, time to first rescue analgesia, and adverse events were observed. Data analysis was done using SPSS version 17.0 (SPSS Statistics Inc., Chicago, IL, USA). Results The mean time taken for the onset of sensory and motor blockade was least in Group D followed by Group C. Duration of sensory and motor blockade was prolonged in Group D. Patients in Group A experienced more hypotension than Groups B, C, and D. Requirement of rescue analgesia was delayed in Groups C and D. Conclusions Administering 25 µg (0.5 mL) of Fentanyl separately after 15 mg (3.0 mL) of 0.5% hyperbaric bupivacaine results in early onset and prolonged duration of sensory and motor blockade, intraoperative hemodynamic stability, the delayed requirement of rescue analgesia postoperatively, and fewer side effects compared to its co-administration as a premixed solution or antecedent to hyperbaric bupivacaine.

Comparison of sequential versus pre mixed administration of intrathecal fentanyl with hyperbaric bupivacaine for patients undergoing elective Caesarean section at Zewditu memorial referral hospital: A prospective cohort study

Background

Spinal anesthesia (SA) is the method of choice for surgery below umbilicus like elective cesarean section. However, Spinal anesthesia is associated with hypotension and limited analgesia duration. To minimize those complications adding opioids like fentanyl either sequentially with separate syringe or pre mixed with local anesthetics become common practice.

Objective

To compare the hemodynamic and analgesic effect of sequential versus pre mixed injection of intrathecal fentanyl with hyperbaric bupivacaine for patients who underwent elective CS under Spinal anesthesia.

Method

A prospective cohort study was performed on parturient who undergone elective cesarean section from 01 January 2020 to 30 March 2020. The decision to give either sequential or premixed drug was based on the responsible anesthetists. Sixty-six American society of Anesthesiologist Ⅱ age ≥18 was recruited. Those who received sequentially were grouped as (S- group) and those who had received pre mixed technique were grouped as (M-group). Data were entered into Epi Info version 7.0 and transported into SPSS Version 22 for analysis. Based on normality assumption, analysis was done by independent t-test for normally distributed data. Whereas Mann –Whitney U test for non-normally distributed data and x2 (Chi-square) test for categorical variable. P-value <0.05 was considered as statistically significant.

Result

Significant reduction in intra operative mean arterial blood pressure was seen in premixed group compared to Sequential group until 15th minute immediately after spinal anesthesia. Thus, the incidence of hypotension was higher in M − group compared to S- group, (p < 0.05). The median Postoperative pain VAS score was significantly lower in the S - group compared to M − group of 4th, 5th and 6th hr. The mean time for 1st rescue analgesic request time was prolonged in the S - group compared to M − group (287.909 ± 15.255 vs. 261.39 ± 25.378) min respectively (p < 0.001).

Conclusion

The Sequential intrathecal injection of fentanyl and hyperbaric bupivacaine provided significant improvement in the blood pressure stability and of sensory and motor block compared to premixed groups.

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Spinal anesthesia is associated with hypotension and limited analgesia duration.

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To minimize those complications adding opioids like fentanyl either pre mixed with local anesthetics or in separate syringe become common practice.

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Sequential intrathecal injection of fentanyl and hyperbaric bupivacaine provided significant improvement in the blood pressure stability and of sensory and motor block compared to premixed groups.

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Longer time to first analgesia request was seen in sequential group compared with premixing group.

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There was significant lower total tramadol consumption in sequential compared with premixing group but comparable total diclofenac consumption.

The Density of Different Local Anesthetic Solutions, Opioid Adjuvants and Their Clinically Used Combinations: An Experimental Study

Various opioids are added to local anesthetic solutions for spinal anesthesia. This may change the final density of the local anestetic (LA) mixture. This effect regarding current concepts in spinal anesthesia needs to be re-evaluated. In order to re-evaluate such effects, hyperbaric and isobaric local anesthetic (LA) solutions were mixed with opioid adjuvants (A) using the equipment available in the operating room. Ten density measurements for each composition (LA-A) were performed. The density change of 0.0006 g/mL was regarded as significant. Measured densities were also compared with theoretical values calculated using Hare's. As a result, the addition of an opioid adjuvant caused a significant reduction in the final density of the LA-A solution. In hyperbaric LA mixtures, it did not change the baricity from hyperbaric to isobaric. However, the addition of highly hypobaric fentanyl 0.99360 g/mL (SD ± 0.00004) changes all isobaric LA solutions baricity to hypobaric. The comparison of measured and theoretical densities revealed significant differences (p > 0.05). However, the absolute reduction reached 0.0006 g/mL in only two LA-A compositions. We conclude that the addition of fentanyl to isobaric LA results in a hypobaric solution that may affect the distribution of the block. The inadequacy of LA-A in a clinical setting is unlikely to influence block characteristics.

Efficacy of premixed versus succedent administration of fentanyl and bupivacaine in subarachnoid block for lower limb surgeries: A randomised control trial

Background and Aims

Subarachnoid block is the most commonly used anaesthesia technique for lower limb surgeries. Opioids are the most commonly used adjuvants with local anesthetics (LA). Adjuvants are given premixed with LA loaded in a single syringe. This study was conducted to evaluate differences in level of sensory and motor block and incidence of hypotension whilst administering hyperbaric bupivacaine and fentanyl either in a single syringe or different syringes. The effect of administering opioid prior to LA and vice versa on these parameters was also assessed.

Methods

One hundred and twenty patients were randomly allocated into three groups of 40 each: Group A received premixed 0.5% heavy bupivacaine 2.5 ml (12.5 mg) and 0.5 ml (25 microgram) of fentanyl in a single 3.0 ml syringe, Group B received 0.5 ml (25 microgram) of fentanyl in a 3.0 ml syringe followed by 0.5% heavy bupivacaine 2.5 ml (12.5 mg) in a 3.0 ml syringe, Group C received 0.5% heavy bupivacaine 2.5 ml (12.5 mg) in a 3.0 ml syringe followed by 0.5 ml (25 microgram) fentanyl in a 3.0 ml syringe. All statistical calculations were done using SPSS 21 version statistical program for Microsoft Windows.

Results

The mean time for onset of sensory and motor block was least in group C followed by group B. The duration of sensory and motor block was prolonged in groups B and C. Patients in group A experienced more hypotension as compared to groups B and C.

Conclusion

Administering hyperbaric bupivacaine first followed by fentanyl leads to an early onset and prolonged duration of sensory and motor block.

Sequential intrathecal injection of fentanyl and hyperbaric bupivacaine at different rates: does it make a difference? A randomized controlled trial

Background

Previous studies have shown that sequential intrathecal injection of fentanyl and hyperbaric bupivacaine for cesarean section (CS) anesthesia provides a superior anesthetic effect than use of bupivacaine alone, and prolongs postoperative analgesia. Herein, we investigated whether rapid intrathecal injection of fentanyl followed by slow injection of hyperbaric bupivacaine affects the duration of postoperative analgesia, the effectiveness of anesthesia, and hemodynamic status.

Methods

Fifty-six parturients with American Society of Anesthesiologists physical status I or II, aged 18–40 years, and scheduled to undergo elective CS were randomly assigned to 2 groups of 28 patients each. The normal sequential group received sequential intrathecal injections of fentanyl and hyperbaric bupivacaine at the same rate, each with a 5 ml syringe. The rapid sequential group received a rapid intrathecal injection of fentanyl with an insulin syringe, followed by a slow injection of hyperbaric bupivacaine with a 5 ml syringe. The onset of sensory block, the timing of the first rescue analgesia, the doses of rescue analgesics, the degree of postoperative pain, the onset and duration of motor block, the incidence and duration of hypotension, and spinal anesthesia-related complications were recorded.

Results

While both approaches had comparable spinal anesthesia-related complications, incidence and duration of hypotension, and doses of ephedrine, the rapid sequential group exhibited a more rapid onset of sensory block, a higher sensory level, and more prolonged postoperative analgesia.

Conclusions

Rapid sequential injection of fentanyl and hyperbaric bupivacaine produced superior anesthesia and more prolonged postoperative analgesia than sequential injections of both at the same rate.

The Effect of Different Doses of Intrathecal Hyperbaric Bupivacaine Plus Sufentanil in Spinal Anesthesia for Cesarean Sections

Background

Decreasing side effects and improving the quality of block in caesarean sections by appropriate dosage of local anesthetics and adjuvants could play an important role in the safe management of cesarean section. The present study aimed at comparing the effects of 3 different doses of intrathecal hyperbaric bupivacaine injected with a fixed dose of sufentanil in cesarean sections.

Methods

In a double- blind randomized clinical trial, 105 candidates of elective cesarean section were randomly assigned into 3 groups of 8, 9, and 10 mg of intrathecal bupivacaine plus sufentanil 2.5 µg. The maximum level of sensory block, the intensity of motor block, and vital signs were measured at regular intervals. The incidence of hypotension and bradycardia were also recorded.

Results

No significant difference was found between the maximum level of sensory block and the intensity of motor block in 3 groups. The incidences of hypotension and bradycardia as well as administration of atropine and ephedrine were comparable among the 3 groups (P > 0.05).

Conclusions

According to similar effects of different doses of bupivacaine, administration of lower doses of bupivacaine (8mg) is more reasonable for spinal anesthesia for cesarean section.

Two syringe spinal anesthesia technique for cesarean section: A controlled randomized study of a simple way to achieve more satisfactory block and less hypotension

BACKGROUND

Multiple trials have been tried to prevent hypotension during spinal anesthesia. However, the drug choice and mode of administration is still a matter of debate.

OBJECTIVES

To compare the outcome of spinal injection of hyperbaric bupivacaine and fentanyl separately to standard injection of mixed fentanyl with hyperbaric bupivacaine.

SETTINGS AND DESIGN

A randomized, controlled clinical trial.

PATIENTS AND METHODS

One hundred twenty-four parturient scheduled for elective cesarean section were randomly allocated into two groups, each 62 parturient: Group M received spinal anesthesia using 10 mg bupivacaine 0.5% premixed with 25 μg fentanyl in the same syringe and Group S received 25 μg fentanyl in one syringe and 10 mg bupivacaine 0.5% without barbotage in a second syringe.

RESULTS

Patients with intraoperative pain that was controllable without the need for a shift to general anesthesia was significantly lower in Group S (3.2%) than in Group M (16.1%). The frequency of hypotension was significantly lower in Group S compared to Group M (P < 0.05). Time till the onset of sensory block was nonsignificantly shorter with nonsignificantly higher mean level of maximal sensory block in Group S compared to Group M (P > 0.05). There was no significant difference in the time till occurrence of hypotension, duration of hypotension, mean dose of ephedrine used for the treatment of hypotension and frequency of patients developed itching between the groups (P > 0.05).

CONCLUSION

Separate intrathecal injection of fentanyl and hyperbaric bupivacaine provided a significant improvement in the quality of sensory block and significant reduction of the frequency of hypotension compared to injection of mixed medications.

Intrathecal clonidine with hyperbaric bupivacaine administered as a mixture and sequentially in caesarean section: A randomised controlled study

BACKGROUND AND AIMS

Mixing adjuvants with hyperbaric bupivacaine in a single syringe before injecting the drugs intrathecally is an age old practice. In doing so, the density of the hyperbaric solution and also of the adjuvant drugs may be altered, thus affecting the spread of drugs. Administering local anaesthetic and the adjuvants separately may minimise the effect of the changes in densities. We aimed to compare block characteristics, intraoperative haemodynamics and post-operative pain relief in parturients undergoing caesarean section (CS) after administering hyperbaric bupivacaine and clonidine intrathecally as a mixture and sequentially.

METHODS

In this single-blind prospective randomised controlled study at a tertiary care centre from 2010 to 12, 60 full-term parturients scheduled for elective CSs were divided into two groups on the basis of technique of intrathecal drug administration. Group M received mixture of clonidine (75 mcg) and hyperbaric bupivacaine 0.5% (10 mg) intrathecally, whereas Group B received clonidine (75 mcg) followed by hyperbaric bupivacaine 0.5% (10 mg) through separate syringes. Observational descriptive statistics, analysis of variance test, Wilcoxon test and Chi-square test were used as applicable.

RESULTS

Duration of analgesia was significantly longer in Group B (474.33 ± 20.79 min) in which the drug was given sequentially than in Group M (337 ± 18.22 min). Furthermore, the time to achieve highest sensory block and complete motor block was significantly less in Group B without any major haemodynamic instability and neonatal outcome.

CONCLUSIONS

When clonidine and hyperbaric bupivacaine were administered in a sequential manner, block characteristics improved significantly compared to the administration of the mixture of the two drugs.

Efficacy of premixed versus sequential administration of clonidine as an adjuvant to hyperbaric bupivacaine intrathecally in cesarean section

Background:

Density of the drugs injected intrathecally is an important factor that influences spread in the cerebrospinal fluid. Mixing adjuvants with local anesthetics (LA) alters their density and hence their spread compared to when given sequentially in seperate syringes.

Aims:

To evaluate the efficacy of intrathecal administration of hyperbaric bupivacaine (HB) and clonidine as a mixture and sequentially in terms of block characteristics, hemodynamics, neonatal outcome, and postoperative pain.

Setting and Design:

Prospective randomized single blind study at a tertiary center from 2010 to 2012.

Materials and Methods:

Ninety full-term parturient scheduled for elective cesarean sections were divided into three groups on the basis of technique of intrathecal drug administration. Group M received mixture of 75 μg clonidine and 10 mg HB 0.5%. Group A received 75 μg clonidine after administration of 10 mg HB 0.5% through separate syringe. Group B received 75 μg clonidine before HB 0.5% (10 mg) through separate syringe.

Statistical analysis used:

Observational descriptive statistics, analysis of variance with Bonferroni multiple comparison post hoc test, and Chi-square test.

Results:

Time to achieve complete sensory and motor block was less in group A and B in which drugs were given sequentially. Duration of analgesia lasted longer in group B (474.3 ± 20.79 min) and group A (472.50 ± 22.11 min) than in group M (337 ± 18.22 min) with clinically insignificant influence on hemodynamic parameters and sedation.

Conclusion:

Sequential technique reduces time to achieve complete sensory and motor block, delays block regression, and significantly prolongs the duration of analgesia. However, it did not matter much whether clonidine was administered before or after HB.