Efficacy of low-dose bupivacaine in spinal anaesthesia for Caesarean delivery: systematic review and meta-analysis

Incidence and factors associated with failed spinal anaesthesia among patients undergoing surgery: a multi- center prospective observational study

BACKGROUND

Failed spinal anaesthesia causes prolonging of operation time, insufficient analgesia for surgery and needs repeating spinal anaesthesia which in turn causes local anaesthesia toxicity, high spinal and total spinal, and conversion to general anaesthesia. However, the problem remains unexplored in Amhara regional state comprehensive specialized hospitals.

OBJECTIVE

To determine incidence and factors associated with failed spinal anaesthesia among patients undergoing surgery in selected Amhara National Regional State comprehensive specialized hospitals, Northwest Ethiopia, 2023.

METHODS

Multi-center prospective observational study was conducted. Data was collected using questionnaire and checklist. All consecutive scheduled emergency and elective patients were included in the study. Data was transformed from Epi data to SPSS and logistic regression analysis was done. Both crude and adjusted odds ratio were used to assess the strength of association. Variables with a p-value of less than 0.05 were considered as statistically significant.

RESULTS

A total of 532 patients were included in this study with a response rate of 98%. Incidence of failed spinal anaesthesia was 22.4% (CI = 19-25.9). Emergency surgery (AOR = 7.01, CI = 4.5-12.7), dose of bupivacaine of ≤ 10 mg (AOR = 3.02, CI = 1.3-10.2), work experience of anaesthetist < 2 years (AOR = 3.1, CI = 1.7-5.72), bloody CSF (AOR = 8.5, CI = 2.53-18.5), hyperbaric local anaesthetic drug (AOR = 3.3, 95% CI = 3.2-8.2) and local anaesthetist without adjuvants (AOR = 5.25, CI = 2.62-14.2) were associated failed spinal anaesthesia.

CONCLUSION AND RECOMMENDATION

The incidence of failed spinal anaesthesia was high in Amhara Region comprehensive specialized hospitals. We suggest that anaesthesia providers should minimize failure by using adjuvants and appropriate dose of local anaesthetic. Additionally, simulation training should be given for anaesthesia trainees to improve their skills and to produce competent professionals.

Comparison of the ED50 of prophylactic butorphanol in preventing morphine-induced pruritus with or without palonosetron: a prospective, double-blinded, randomized dose-response trial using an up-down sequential allocation method

BACKGROUND

Butorphanol has been used to reduce the incidence and severity of neuraxial morphine-induced pruritus. Palonosetron is a commonly used antiemetic for the prevention of postoperative nausea and vomiting. The aim of our study was to compare the effective dose in 50% of subjects (ED50) of intravenous butorphanol infusion with or without a single intravenous bolus of palonosetron for preventing pruritus induced by epidural administration of morphine.

METHODS

A total of 120 parturients were randomly assigned to receive an intravenous bolus injection of palonosetron plus continuous infusion of butorphanol (Group P + B) or an intravenous bolus of saline plus continuous infusion of butorphanol (Group B) after epidural administration of morphine. The antipruritic effect was graded as satisfactory (numerical rating scale (NRS) of pruritus ≤3) or unsatisfactory (NRS >3) within 48 h after morphine treatment. The first patient in each group received butorphanol infusion at a rate of 4 µg/kg/h. The infusion dose for each subsequent patient in the corresponding group was increased by 0.2 µg/kg/h after an unsatisfactory response or decreased by 0.2 µg/kg/h after a satisfactory response. The ED50 was calculated for each group and compared using up-down sequential analysis.

RESULTS

The ED50 (mean [95% confidence interval (CI)]) of the dose of intravenous butorphanol infusion for preventing moderate to severe pruritus was lower in Group P + B (3.29 µg/kg/min [3.25-3.34 µg/kg/min]) than in Group B (3.57 µg/kg/min [3.47-3.67 µg/kg/min]) (p < 0.05).

CONCLUSIONS

Under the conditions of the present study, a prophylactic use of 0.25 mg palonosetron reduced the ED50 of prophylactic infusion of butorphanol by approximately 8% to achieve a satisfactory antipruritic effect after epidural morphine for post-caesarean analgesia.

Effect of height versus height/weight-based spinal bupivacaine on maternal hemodynamics for elective cesarean in short stature patients: a randomized clinical trial

PURPOSE

Doses of spinal bupivacaine adjusted to patient height or height/weight have been shown to provide hemodynamic stability during cesarean section. However, their effects in short stature parturients are unknown.

METHODS

In this double-blind, randomized clinical trial, we randomly assigned short parturients (height < 150 cm) undergoing elective cesarean section, to receive doses of intrathecal hyperbaric bupivacaine either height or height/weight-adjusted, in a 1:1 ratio. The primary outcome was post-spinal hypotension (defined as systolic blood pressure [SBP] < 90% of baseline between spinal administration and delivery of the baby). Secondary outcomes included severe post-spinal hypotension (SBP < 80% of baseline), post-delivery hypotension (SBP < 90% and < 80% of baseline), intraoperative bradycardia, nausea and vomiting, shivering, rescue analgesic needed, and spinal block characteristics.

RESULTS

A total of 112 patients underwent randomization. Post-spinal hypotension (SBP < 90% of baseline) occurred in 52% of the patients in the height/weight group and in 55% in the height group (difference - 3.5%: 95% confidence interval [CI] - 22 to 14.8, P = 0.705). There was no significant difference between the two groups in the occurrences of post-spinal severe hypotension (SBP < 80% of baseline), post-delivery hypotension, and spinal block characteristics. Six patients (11%) in the height/weight group needed intraoperative rescue analgesic compared to none in the height group (P = 0.027).

CONCLUSION

We found that height-based dosing in short parturients provides the optimal trade-off between intraoperative hemodynamic instability and provision of pain-free anesthesia.

TRIAL REGISTRATION

clinicaltrial.gov-NCT04082676. https://clinicaltrials.gov/ct2/show/NCT04082676 .

Intrathecal dexmedetomidine as an adjuvant to plain ropivacaine for spinal anesthesia during cesarean section: a prospective, double-blinded, randomized trial for ED50 determination using an up-down sequential allocation method

BACKGROUND

Intrathecal dexmedetomidine, as an adjuvant to local anesthetics, has been reported to improve the quality of spinal anesthesia and reduce the required local anesthetic dose. However, the optimal dosage regimen for intrathecal dexmedetomidine combined with plain ropivacaine for cesarean section (CS) remains undetermined. The present study aimed to determine the median effective dose (ED50) of intrathecal dexmedetomidine as an adjuvant to plain ropivacaine for spinal anesthesia during CS.

METHODS

Sixty parturients undergoing CS were randomly assigned to either group: plain ropivacaine 8 mg (Group Rop8) or plain ropivacaine 10 mg (Group Rop10). The initial dosage of intrathecal dexmedetomidine in each group was 5 µg. The effective dose was defined as a bilateral sensory block at the level of T6 or above to pinprick attained within 10 min after intrathecal injection, without the need for supplementary intraoperative epidural anesthesia. Effective or ineffective responses were determined, followed by a 1 µg increment or decrement in the dose of intrathecal dexmedetomidine for the next parturient using up-down sequential allocation. ED50 were calculated using probit regression.

RESULTS

The ED50 of intrathecal dexmedetomidine with plain ropivacaine was 5.9 µg (95% confidence interval [CI], 4.9-7.4 µg) in Group Rop8 and 3.1 µg (95% CI, 0.1-4.8 µg) in Group Rop10 (P < 0.05). Hemodynamic stability, side effects, patient satisfaction and neonatal outcomes were comparable between the two groups.

CONCLUSIONS

The present data suggested that the ED50 of intrathecal dexmedetomidine as an adjuvant to 8 mg and 10 mg plain ropivacaine in spinal anesthesia during cesarean section was approximately 6 µg and 3 µg, respectively.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, identifier: ChiCTR2200055928.

Current status of the combined spinal-epidural technique in obstetrics and surgery

Epidural and spinal blocks are well-accepted neuraxial techniques but both have several disadvantages. Combined spinal-epidural (CSE) can combine the best features of both techniques and reduce or eliminate these disadvantages. It provides the rapidity, density, and reliability of subarachnoid block with the flexibility of catheter epidural technique to extend the duration of anesthesia/analgesia (and to improve spinal block). It is an excellent technique for determining minimum intrathecal drug doses. Although most commonly employed in obstetric practice, CSE is also used in a wide variety of non-obstetric surgical procedures including orthopedic, vascular, gynecological, urological, and general surgical procedures. The needle-through-needle technique remains the most commonly used method to perform CSE. Several technical variations including Sequential CSE and Epidural Volume Extention (EVE) are commonly used particularly in obstetric and high-risk patients such as those with cardiac disease where a slower onset of sympathetic block is desirable. The risks of complications such as epidural catheter migration through the dural hole, neurological complications, and subarachnoid spread of epidurally administered drugs are possible but have not been a clinically relevant problem in the 40+ years of their existence. In obstetrics, CSE is used for labor pain because it produces rapid-onset analgesia with reduced local anesthetic consumption and less motor block. The epidural catheter placed as part of a CSE is more reliable than a catheter placed as part of a conventional epidural. Less breakthrough pain throughout labor is noted and fewer catheters require replacing. Side effects of CSE include greater potential for hypotension and more fetal heart rate abnormalities. CSE is also used for cesarean delivery. The main purpose is to decrease the spinal dose so that spinal-induced hypotension can be reduced. However, reducing the spinal dose requires an epidural catheter to avoid intra-operative pain when surgery is prolonged.

A Comparative Study on the Effect of Intrathecal Bupivacaine vs. Ropivacaine on Maternal and Neonatal Outcomes After Cesarean Section: A Systematic Review and Meta-analysis

Context

The type of anesthesia in cesarean section can affect the mother and baby. This study aimed to determine the comparative effect of intrathecal hyperbaric bupivacaine vs. hyperbaric ropivacaine on maternal and neonatal outcomes after cesarean section.

Evidence Acquisition

PubMed, Web of Science, Embase, Google Scholar, IranDoc, MagIran, and Scopus databases were searched from 1 September 2022 to 1 November 2022. Eighteen clinical trials with 1542 patients were included in the analysis.

Results

There was no statistically significant difference in hypotension, bradycardia, and Apgar score between the 2 groups (P > 0.05). The risk of nausea (relative risk (RR), 1.526; 95% CI, 1.175 - 1.981; P = 0.001) and vomiting (RR, 1.542; 95% CI, 1.048 - 2.268; P = 0.02) caused by bupivacaine was 0.53% and 0.54% higher than that of ropivacaine. The incidence of shivering (RR, 2.24; 95% CI, 1.480 - 3.39; P = 0.00) was 2.24 times higher in the bupivacaine group than in the ropivacaine group. The average onset time of sensory block (standardized mean difference (SMD), -0.550; 95% CI, -1.054 to -0.045; P = 0.032) and motor block (SMD, -0.812; 95% CI, -1.254 to -0.371; P = 0.000) was significantly lower in the bupivacaine group than in the ropivacaine group.

Conclusions

Despite the fact that ropivacaine and bupivacaine are effective in cesarean section, ropivacaine is more favorable because of less hemodynamic changes, less duration of sensory and motor block, and fewer side effects, which are effective in patient recovery.

Consensus on the Southeast Asian management of hypotension using vasopressors and adjunct modalities during cesarean section under spinal anesthesia

BACKGROUND AND AIMS

This consensus statement presents a comprehensive and evidence-based set of guidelines that modify the general European or US guidelines for hypotension management with vasopressors during cesarean delivery. It is tailored to the Southeast Asian context in terms of local human and medical resources, health system capacity, and local values and preferences.

METHODS AND RESULTS

These guidelines were prepared using a methodological approach. Two principal sources were used to obtain the evidence: scientific evidence and opinion-based evidence. A team of five anesthesia experts from Vietnam, the Philippines, and Thailand came together to define relevant clinical questions; search for literature-based evidence using the MEDLINE, Scopus, Google Scholar, and Cochrane libraries; evaluate existing guidelines; and contextualize recommendations for the Southeast Asian region. Furthermore, a survey was developed and distributed among 183 practitioners in the captioned countries to gather representative opinions of the medical community and identify best practices for the management of hypotension with vasopressors during cesarean section under spinal anesthesia.

CONCLUSIONS

This consensus statement advocates proactive management of maternal hypotension during cesarean section after spinal anesthesia, which can be detrimental for both the mother and fetus, supports the choice of phenylephrine as a first-line vasopressor and offers a perspective on the use of prefilled syringes in the Southeast Asian region, where factors such as healthcare features, availability, patient safety, and cost should be considered.

Accuracy of Spinal Anesthesia Drug Concentrations in Mixtures Prepared by Anesthetists

OBJECTIVE

Medication errors include the indirect dosing of drugs. For spinal anesthesia mixtures of local anesthetics, opioids are drawn from ampoules and combined in a syringe, according to clinical practice. We set out to determine the accuracy of the drug mixtures.

METHODS

Physicians of our department were invited to prepare the mixture used for spinal anesthesia for cesarean section, consisting of 10-mg hyperbaric bupivacaine (2-mL volume), 20-μg fentanyl (0.4-mL volume), and 100-μg morphine (0.1-mL volume). Concentrations of these drugs were determined by means of high performance liquid chromatography. Interindividual and intraindividual variations were assessed.

RESULTS

We analyzed 96 samples from 31 physicians. Fifty-one percent of the measured bupivacaine concentrations were in ±10% deviation range of the intended concentration; 17% of the fentanyl and 24% of the morphine concentrations were in this range. A total of 2.1% of the samples had a bupivacaine concentration corresponding to a dose of 8 mg or less, and 11.5% of the samples had a morphine concentration corresponding to a dose of 150 μg or greater. Intraindividual variations were 10.9% for bupivacaine, 24.7% for fentanyl, and 38.9% for morphine.

CONCLUSIONS

Our results show a high deviation of the obtained from the intended concentrations. Two percent of the samples had bupivacaine concentrations that probably resulted into an insufficient analgesia, and 11% of the samples had morphine concentrations that, according to guidelines, would require a longer monitoring period than with the intended dose.

Maternal and neonatal outcomes with the addition of intrathecal midazolam as an adjuvant to spinal anesthesia in cesarean delivery: A systematic review and meta-analysis of randomized controlled trials

STUDY OBJECTIVE

To determine the efficacy and safety, in terms of maternal and neonatal outcomes, of adding intrathecal midazolam to spinal anesthesia for cesarean delivery in healthy pregnant women.

DESIGN

A meta-analysis of randomized controlled trials was conducted. PubMed, Cochrane Library, Embase, and Web of Science were searched manually, and citation screening was completed on May 20, 2021.

SETTING

Most of the included data were collected in the operating room and postoperative recovery area.

PATIENTS

A total of 1382 healthy parturients undergoing cesarean delivery with single-shot spinal anesthesia were recruited in 19 eligible randomized controlled trials.

INTERVENTIONS

Single intrathecal midazolam adjuvant was compared to a control, with the local anesthetic dose in spinal anesthesia identical between the intervention and control groups.

MEASUREMENTS

The primary outcomes were time to first analgesic use, maternal adverse effects, and neonatal Apgar scores at 1 and 5 min. The secondary outcomes were the onset and duration of the sensory and motor blocks.

MAIN RESULTS

Adjuvant intrathecal midazolam prolonged the time to the first analgesic (mean difference [MD]: 59.96 min, 95% confidence interval [CI]: [23.12, 96.79]) and decreased perioperative maternal nausea and/or vomiting (odds ratio [OR], 0.28; 95% CI: [0.17, 0.45]). However, more sedation events were observed with midazolam (OR, 3.93; 95% CI: [1.12, 13.78]). There was no significant difference in the neonatal Apgar scores at 1 or 5 min (MD: -0.29, 95% CI: [-0.61, 0.03]; MD: -0.00, 95% CI: [-0.11, 0.1], respectively). Intrathecal midazolam also shortened sensory and motor block onset by less than 1 min and prolonged sensory block duration but had no significant effect on motor block duration.

CONCLUSIONS

Current evidence indicates that intrathecal midazolam, as an adjuvant to spinal anesthesia, provides modest analgesic and significant antiemetic effects at the cost of more sedation events in cesarean delivery patients. The neonatal Apgar score was not affected by intrathecal midazolam administration. However, more objective, sensitive, and long-term measurements of neonatal safety and maternal neurological effects should be performed in the future.

Hemodynamic and analgesic effect of intrathecal fentanyl with bupivacaine in patients undergoing elective cesarean section; a prospective cohort study

Background

Spinal anesthesia with bupivacaine has side effects such as hypotension, respiratory depression, vomiting, and shivering. The side effects are dose-dependent, therefore different approaches have been attempted to avoid spinal-induced complications including lowering the dose of local anesthetic and mixing it with additives like Neuraxial opioids.

Objective

To compare the Hemodynamic and analgesic effects of intrathecal fentanyl as an adjuvant with low and conventional doses of bupivacaine in patients undergoing elective cesarean section under spinal anesthesia.

Methodology

An institutional-based prospective cohort study was conducted on 90 patients. Data was collected with chart review, intraoperative observation, and postoperatively patient interview. Data was entered into EPI INFO and transport to SPSS version 23 for analysis of variables using one-way ANOVA, Kruskal Wallis H rank test, and chi-square.

Result

Hypotension but not bradycardia, was significantly frequent in a conventional dose of bupivacaine alone (CB) group and a conventional dose of bupivacaine with fentanyl (CBF) groups than that of the lower dose of bupivacaine with fentanyl (LBF) groups. Duration of analgesia was significantly longer in LBF (248± 35.6 minutes) and in CBF groups (260.3±40.3 minutes) than in CB group (167.10 ± 31.45 minutes). Time for the first analgesic request was significantly later in LBF (304±47.8 minutes) and CBF (294.6±99.5 minutes) groups than that in CB group (177±25.88 minutes).

Conclusion

The Lower dose of bupivacaine is associated with less risk of hypotension and faster recovery. Adding fentanyl with the lower dose of bupivacaine in spinal anesthesia for cesarean section could provide comparable anesthesia with the lower risk of hypotension and longer postoperative analgesia.

A Height-Based Dosing Algorithm of Bupivacaine in Spinal Anesthesia for Decreasing Maternal Hypotension in Cesarean Section Without Prophylactic Fluid Preloading and Vasopressors: A Randomized-Controlled Non-Inferiority Trial

Background

There is a high incidence of maternal hypotension in spinal anesthesia for cesarean section. The aim of the study is to investigate whether there is a height-based dosing algorithm of bupivacaine that provides adequate anesthesia with less maternal hypotension.

Methods

There were 2 groups of 280 parturients who did not receive prophylactic fluid preloading: Test and Conventional group. In Test group, a height based dosing algorithm was used to confirm the dose of bupivacaine in parturients without prophylactic vasopressors. In the Conventional group, a constant dose of bupivacaine was used. The complications and quality of anesthesia were evaluated.

Results

In the Conventional group, the shorter participants had higher incidence of hypotension, faster sensory block time, and more participants with complete motor block (p = 0.030, 2.957 × 10^-14, and 0.012). In the Test group, the incidence of hypotension, sensory block time, and number of participants with complete motor block did not change with height (p = 0.199, 0.617, and 0.209). The height-based dosing algorithm of bupivacaine decreased the incidence of hypotension (p = 0.004), induced lower sensory block level and less degree of motor block (p = 3.513 × 10^-7 and 5.711 × 10^-11). The quality of analgesia, quality of muscle relaxation, and degree of intraoperative comfort were similar in both groups (p = 0.065, 0.498, and 0.483).

Conclusions

The height influences the dose of bupivacaine in spinal anesthesia; without prophylactic fluid pre-loading and vasopressors, the height-based dosing algorithm of bupivacaine is suitable, and meets the cesarean section' requirement with less maternal hypotension.

Clinical Trial Registration

www.ClinicalTrials.gov, identifier: NCT03497364.

Effect of bupivacaine intraperitoneal and intra-abdominal bicarbonate in reducing postoperative pain in laparoscopic cholecystectomy: a double-blind randomized clinical trial study

Objective

We aimed to compare the effect of bupivacaine intraperitoneal with intra-abdominal bicarbonate in reducing postoperative pain in laparoscopic cholecystectomy.

Results

In this double-blind randomized clinical trial study, 58 patients underwent laparoscopic cholecystectomy referred to a hospital in Tehran, Iran (2019), were assigned into three groups: at the end of the surgery, spraying 50 cc of bupivacaine 0.2% through the laparoscopic port; or rinsing the abdomen with 5.7% bicarbonate dissolved in 1000 cc of normal saline; or abdominal lavage with normal saline. Pain of patients was evaluated according to visual analogue scale criteria and means Ramsay score in recovery times, 2, 8 and 24 h and post-operative analgesia satisfaction score at 2 and 24 h were also evaluated. The mean age of range was 44.26 ± 13.13 years, 44 female patients and 14 male patients. The mean Ramsay score in recovery, 2, 8 and 24 h postoperative times was not significantly different among the groups. Comparing post-operative analgesic satisfaction scores in recovery, 2 and 24 h revealed no significant difference among the groups. We found that use of bupivacaine intraperitoneal and intra-abdominal bicarbonate decreased pain after laparoscopic cholecystectomy but the decrease was more in bupivacaine group than bicarbonate group.

Trial Registration: Retrospectively registered, IRCT20180723040570N1; date of registration: 2019-06-24.

Neuraxial and general anaesthesia for caesarean section

Caesarean section (CS) is one of the most performed operations worldwide. In many parts of the world, there has been a reduction in anaesthetic associated obstetric mortality, and this has been attributed to the increased use of neuraxial anaesthesia and improved safety of general anaesthesia, alongside improved training and organisational changes. In resource-limited countries, anaesthesia contributes disproportionately to maternal mortality, with one in seven deaths being due to anaesthesia. A major contributory factor to this is the severe shortage of trained anaesthetic providers. Goals for anaesthesia for CS include the woman's comfort and foetal well-being, focusing on strategies to minimise morbidity and mortality for both. Anaesthetic options for CS include neuraxial techniques (spinal or combined-spinal epidural or epidural extension of labour analgesia) and general anaesthesia. There is increasing evidence of the benefit of neuraxial techniques over general anaesthesia in terms of maternal and foetal outcomes. For elective CS, spinal and combined-spinal anaesthesia predominate. General anaesthesia is mainly reserved for Category 1 CS where there is an immediate threat to the life of the mother or the baby. This review discusses the practical aspects of neuraxial and general anaesthesia for CS.

Analysis of Risk Factors for Intraoperative Hypotension in Cesarean Section and Poor Prognosis of Neonates

Objective

To analyze the risk factors of intraoperative hypotension in cesarean section women and poor prognosis of neonates.

Methods

The clinical data of 1071 cesarean section women admitted to The Affiliated Jiangning Hospital of Nanjing Medical University from January 2021 to December 2021 were retrospectively analyzed. They were divided into hypotension group (n = 472) and normal control group (n = 599) according to whether there was hypotension during operation. The correlations between the clinical data of cesarean section and the occurrence of intraoperative hypotension and poor prognosis of neonates were analyzed by logistic regression analysis. Receiver operating curve (ROC) was drawn and the area under the curve (AUC) was calculated.

Results

Logistic regression analysis results showed that BMI ≥30 kg/m2, infant weight ≥3500 g, spinal anesthesia, puncture site L2-3, bupivacaine dose>10 mg, ropivacaine dose>50 mg, and perfusion index≥4 were the risk factor for intraoperative hypotension in cesarean section (p < 0.01) and BMI ≥30 kg/m2, umbilical cord around neck, spinal anesthesia, and perfusion index≥4 were risk factors for poor prognosis of neonates (p < 0.01). The AUC of ROC for BMI to diagnose intraoperative hypotension in cesarean section women was 0.6240 (95% CI: 0.59-0.66, p < 0.01), the sensitivity was only 30.20% (95% CI: 26.73%-35.02%), and the specificity was 87.65% (84.77%-90.04%), and the AUC of BMI for the diagnosis of poor prognosis of neonates was 0.5647 (95% CI: 0.5013-0.6280, p = 0.049), and the sensitivity was 51.19% (95% CI: 40.69%-61.59%), and the specificity was 64.34% (61.30%-67.26%). The AUC of perfusion index for the diagnosis of intraoperative hypotension in cesarean section women was 0.8333 (95% CI: 0.8081-0.8584, p < 0.01), the sensitivity was 94.49% (95% CI: 92.05%-96.21%), and the specificity was 73.12% (69.43%-76.52%); the AUC of perfusion index for the diagnosis of ROC with poor prognosis of neonates was 0.6164 (95% CI: 0.5538-0.6791, p < 0.01), the sensitivity was 70.24% (95% CI: 59.75%-78.96%), and the specificity was 50.86% (47.75%-53.97%).

Conclusion

The prediction model established by BMI, infant weight, anesthesia method, puncture site, anesthetic drug dose, and perfusion index has guiding value for clinical prediction of cesarean section maternal hypotension. The prediction model established by BMI, umbilical cord around neck, anesthesia method, and perfusion index has guiding value for clinical prediction of poor prognosis of neonates.

Comparison of equipotent doses of intrathecal hyperbaric prilocaine 2% and hyperbaric bupivacaine 0.5% for elective caesarean section: A prospective, randomised, controlled, two-centre clinical trial

BACKGROUND

Elective caesarean section is performed mainly under spinal anaesthesia using hyperbaric bupivacaine combined with opioids. Despite rapid onset, good quality anaesthesia, bupivacaine provides a long duration of motor block and is related to maternal hypotension. Current policies appeal for implementation of enhanced recovery procedures after caesarean section. Hyperbaric prilocaine is an intermediate-acting local anaesthetic known for its efficacy in ambulatory surgery. Evidence on the clinical relevance of intrathecal prilocaine use for caesarean section is currently lacking.

OBJECTIVES

We aimed to investigate whether hyperbaric prilocaine would offer a shorter motor block and recovery than bupivacaine, when comparing equipotent doses. We also assessed the characteristics of sensory block, maternal haemodynamics and side effects for both mother and newborn.

DESIGN

Prospective, randomised, double-blind, controlled, two-centre, clinical trial.

SETTING

One university teaching hospital and one general teaching hospital in Brussels, Belgium.

PATIENTS

American Society of Anesthesiologists' physical status 2 parturients (n = 40) undergoing caesarean section under spinal anaesthesia.

INTERVENTIONS

Patients were randomly assigned to receive spinal anaesthesia using hyperbaric prilocaine 50 mg or hyperbaric bupivacaine 10 mg, both given with sufentanil 2.5 μg and morphine 100 μg. An epidural catheter was introduced as a backup in case of failure.

MAIN OUTCOMES

The primary outcome was the motor block regression (modified Bromage scale 1 to 6). Secondary outcomes included sensory block characteristics, first unassisted ambulation, maternal side effects, newborns' parameters and overall satisfaction.

RESULTS

Median [IQR] motor block was significantly shorter in the hyperbaric prilocaine group (110 [104 to 150] min versus 175 [135 to 189] min, P = 0.001). First unassisted ambulation was achieved earlier after prilocaine (204.5 [177 to 246.5] min versus 314 [209.25 to 400] min, P = 0.007), and the incidence of maternal hypotension was significantly higher with bupivacaine (P = 0.033). No supplementary epidural analgesia was needed.

CONCLUSION

Prilocaine provides shorter motor block, faster recovery and better haemodynamic stability than bupivacaine while offering equivalent surgical anaesthesia.

TRIAL REGISTRATION

Clinicaltrials.gov: NCT02973048, EudraCT: 2016-003010-26.

Sufentanil for Spinal Analgesia during Cesarean Section Delivery: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

OBJECTIVE

To investigate the effect of sufentanil for spinal analgesia during cesarean section.

METHOD

Eligible papers were systematically retrieved from PubMed, Embase, Ovid, and ScienceDirect. Two researchers independently extracted primary and secondary endpoints to compute relative risk and mean difference by using the random-effects model or the fixed-effects model, as appropriate. Publication bias was quantified and assessed using funnel plot and Egger's test.

RESULT

A total of 8 publications with 503 pregnant women were included in this study for meta-analysis. Subarachnoid administration of sufentanil did not significantly reduce the onset time of sensory block and motor block. Nonetheless, subarachnoid administration of sufentanil significantly increased the incidence of postoperative skin pruritus (RR = 5.25, 95%CI: 1.90, 14.49, P < 0.001).

CONCLUSION

Subarachnoid administration of sufentanil has no significant difference in the combined effect value of shortening the onset time of sensory block and motor block, prolonging the onset time of local anesthesia and the incidence of some adverse reactions (such as postoperative nausea, vomiting, hypotension, and tremors). However, the incidence of skin pruritus was significantly increased, and the difference was statistically significant. Because of this, the drug still needs to be used with caution in combination with the actual situation in clinical use.

Low dose and the conventional dose of 0.5% hyperbaric bupivacaine produce comparable outcomes in the lower segment caesarean section. An observational study

Background

Spinal anesthesia with 0.5% hyperbaric bupivacaine is an approved technique for lower segment cesarean sections. This study compared two different hyperbaric bupivacaine doses for spinal anesthesia in the lower segment cesarean section. We hypothesized that low-dose spinal anesthesia had similar outcomes as conventional doses of bupivacaine.

Methods

This was a comparative observational study involving seventy healthy parturients who were posted for elective cesarean section. Patients were supposed to receive 0.5% hyperbaric bupivacaine and were divided into groups, low dose (LB-1.8 ml) and conventional-dose (HB-2.2 ml) group. The extent of motor blockade, sensory blockade, hemodynamic effects, visual analog scale for pain, and patient satisfaction were measured. The data were analyzed using the median and interquartile range for all parameters. A statistical package SSPS version 25.0 was used to do the analysis.

Results

Hemodynamic stability was well maintained in both groups. Almost 100% of the patients in both groups achieved a grade 3 motor blockade in 8 min. T6 level of sensory blockade was achieved in 6 min by 100% of the patients. The low-dose group made a faster recovery compared with the high-dose group.

Conclusion

Low-dose spinal anesthesia can cause similar hemodynamic and analgesic effects as the conventional-dose group. The only benefit of low dose spinal as compared with conventional-dose group was faster recovery from the anesthetic effects.

Comparative study between 2-chloroprocaine and combination of 2-chloroprocaine with fentanyl for spinal anaesthesia

Using fentanyl as an adjuvant in spinal anesthesia has well been documented. Fentanyl being an opioid additive prolongs the duration of neuroaxial blockade without significantly increasing the time to ambulation. Aim: To assess the effect of fentanyl as an adjuvant used with 2-chloroprocaine on sensory and motor onset and offset block time, time for ambulation and complication rate. Methodology: A randomized comparative study was conducted for a period of 6 months in the department of anesthesiology at Kirupananda Variyar medical college and hospital, Salem. A total of 100 patients (50 in each group) posted for elective surgeries in the age group between 20 and 60 were enrolled as our study subjects. Group A patients received intrathecal injection of 3 mL of 1% 2-Chloroprocaine (30 mg) mixed with 0.5 mL of Normal saline and Group B patients received 3 mL of 1% 2-Chloroprocaine (30 mg) mixed with 0.5 mL of Fentanyl solution containing 50 micrograms per mL (25 mcg). Bilateral sensory and motor block onset and regression time was monitored. Results: Time for regression of sensory block, recovery of motor block and time to void urine was comparatively more among group B (2-chloroprocaine with fentanyl) than group A (2-chloroprocaine) and the difference was found to be statistically significant (p < .05). The length of stay in post-anesthesia ICU and the patient satisfaction score did not show a statistical significant difference between the two groups. Similarly no change was noted in hemodynamic parameters and in the incidence of adverse events. Conclusion: We conclude that the addition of fentayl to 2 chloroprocaine has a significant synergistic effect in prolonging postoperative analgesia without prolonging the time for ambulation.

Epidural volume extension technique in high risk obstetric patients – Case series

Epidural volume extension involves injection of normal saline into the epidural space soon after an intrathecal injection, with the aim of augmenting the sensory block height. It has significant dose-sparing effect, providing adequate level of anaesthesia and analgesia with minimal haemodynamic disturbances. We present this case series that shows the successful use of this technique in high risk cardiac patients coming for elective lower segment caesarean section.

Incidence and Effect of Intrathecal Fentanyl Use in Spinal Anesthesia for Cesarean Deliveries in the Community Setting: A Single-Center Observational Retrospective Study

Background: The addition of intrathecal fentanyl to spinal anesthesia for cesarean delivery has been shown to be beneficial, but its rate of utilization in the community setting is unknown. The primary aim of our study was to determine the rate of intrathecal fentanyl use for cesarean deliveries with spinal anesthesia in a community hospital, and our secondary aim was to determine its effect on anesthetic outcomes.

Methods: Patients who underwent cesarean delivery from June 1, 2017 to November 30, 2019 with spinal anesthesia as the initial anesthetic technique were included.

Results: Seven hundred sixty-one cesarean deliveries met inclusion criteria, and 161 (21.2%) patients received intrathecal fentanyl in their spinal anesthetic for cesarean delivery. A multivariate model that controlled for patient weight and time from spinal placement to procedure end showed that patients who received intrathecal fentanyl were less likely to have conversion to general anesthesia or administration of systemic anesthetic adjuncts compared to patients who did not receive intrathecal fentanyl (odds ratio 2.889, 95% CI 1.552-5.903; P=0.0017).

Conclusion: Only 1 in 5 patients received intrathecal fentanyl for cesarean deliveries performed under spinal anesthesia in a community hospital despite known benefits. Patients who did not receive intrathecal fentanyl had increased odds of conversion to general anesthesia or administration of systemic anesthetic adjunct administration, a finding consistent with previous studies. The addition of intrathecal fentanyl to spinal anesthesia for cesarean delivery should be strongly considered in the community setting.

An Observational Study on Arrhythmia During Cesarean Section Under Spinal Anesthesia: Incidence, Risk Factors, and Effects on Immediate Post-delivery Neonatal Outcome

INTRODUCTION

Various types of arrhythmia have been reported during cesarean section under spinal anesthesia. But the possible causative factors and the effects of arrhythmia on immediate post-delivery neonatal outcome are not well established.

METHODS

This prospective observational study was conducted over a period of one year in a tertiary care hospital on women undergoing cesarean section under spinal anesthesia. The objectives of the study were to determine the incidence of arrhythmia, its types, the possible factors influencing arrhythmia, and the immediate post-delivery neonatal outcome. Data collected were analyzed using Statistical Package for the Social Sciences (SPSS) software version 21 (IBM Corp. Armonk, NY).

RESULTS

In our study, the incidence of arrhythmia was 31.9% during cesarean section under spinal anesthesia; and sinus bradycardia was the most common type. Arrhythmia occurred more in women with hypotension, when maximum block height was above T₄ level and dose of intrathecal hyperbaric bupivacaine was more than 2.2 mL (P value <0.05). Also, uterine manipulation led to sudden bradycardia and transient cardiac asystole in two patients which was preceded by subjective symptoms of pain and discomfort. None of the neonates required cardiopulmonary resuscitation or neonatal intensive care unit admission within an hour of birth. APGAR (Appearance (skin color), Pulse (heart rate), Grimace (reflex irritability), Activity (muscle tone), and Respiration) scores at 1 and 5 minutes were similar in all the newborns born to mothers with or without arrhythmia.

CONCLUSION

The occurrence of arrhythmia during cesarean section under spinal anesthesia, though very common, is rarely life-threatening. Keeping maximum level of block height between T₄ and T_6, using lower possible drug dose to provide adequate level of sensory block, prompt management of hypotension, and strict monitoring during uterine manipulation may reduce the overall incidence of arrhythmia. Intraoperative arrhythmia, however, does not adversely affect the immediate post-delivery neonatal outcome.

Efficacy of dexmedetomidine on peritoneal dialysis catheter insertion

PURPOSE

Dexmedetomidine (DEX) is a sedative agent with minimal respiratory and hemodynamic effects. The present study aimed to evaluate its effectiveness in peritoneal dialysis (PD) catheter insertion.

METHODS

This single-center retrospective study included patients who underwent PD catheter insertion under spinal anesthesia in our hospital between January 2016 and December 2020. Patients were divided into the DEX and non-DEX groups according the use of DEX. After 1:1 propensity score matching to adjust for age, sex, body mass index, mean blood pressure (BP), and Charlson comorbidity index, we compared operation-related outcomes, including peak numerical rating scale (NRS), occurrence of nausea, vital signs, or operative time between the two groups.

RESULTS

Of a total of 44 patients, 9 patients received DEX, and 35 did not. After propensity score matching, each group consisted of 8 patients. Peak NRS was significantly lower (P = 0.003) in the DEX group compared with the non-DEX group. Maximum mean BP during the operation was also significantly lower in the DEX group compared with the non-DEX group (P = 0.020), with no significant differences in minimum mean BP between the two groups (P = 0.831). The DEX group showed a trend of shortened operative time (P = 0.068). There were no significant differences in the occurrence of nausea (P = 1.000). Moreover, there was no clinically important adverse event associated with use of DEX.

CONCLUSION

The use of DEX in PD catheter insertion under spinal anesthesia could safely improve operative analgesia.

Fluid loading therapy to prevent spinal hypotension in women undergoing elective caesarean section: Network meta-analysis, trial sequential analysis and meta-regression

BACKGROUND

Fluid loading is one of the recognised measures to prevent hypotension due to spinal anaesthesia in women scheduled for a caesarean section.

OBJECTIVE

We aimed to evaluate the current evidence on fluid loading in the prevention of spinal anaesthesia-induced hypotension.

DESIGN

Systematic review and network meta-analysis with trial sequential analysis and meta-regression.

DATA SOURCES

Medline, Epub, Embase.com (Embase and Medline), Cochrane Central, Web of Science and Google Scholar were used.

ELIGIBILITY CRITERIA

Only randomised controlled trials were used. Patients included women undergoing elective caesarean section who received either crystalloid or colloid fluid therapy as a preload or coload. The comparator was a combination of either a different fluid or time of infusion.

RESULTS

A total of 49 studies (4317 patients) were included. Network meta-analysis concluded that colloid coload and preload offered the highest chance of success (97 and 67%, respectively). Conventional meta-analysis showed that crystalloid preload is associated with a significantly higher incidence of maternal hypotension than colloid preload: risk ratio 1.48 (95% CI 1.29 to 1.69, P < 0.0001, I² = 60%). However, this result was not supported by Trial Sequential Analysis. There was a significant dose–response effect for crystalloid volume preload (regression coefficient = −0.073), which was not present in the analysis of only double-blind studies. There was no dose–response effect for the other fluid regimes.

CONCLUSION

Unlike previous meta-analysies, we found a lack of data obviating an evidence-based recommendation. In most studies, vasopressors were not given prophylactically as is recommended. Studies on the best fluid regimen in combination with prophylactic vasopressors are needed. Due to official european usage restrictions on the most studied colloid (HES), we recommend crystalloid coload as the most appropriate fluid regimen.

TRIAL REGISTRATION

CRD42018099347.

Association Between Hyperbaric Bupivacaine Dose and Maternal Hypotension: Retrospective Database Study of 8226 Women Undergoing Cesarean Delivery Under Spinal Anesthesia

BACKGROUND

Low-dose (≤8 mg) hyperbaric bupivacaine for spinal anesthesia during cesarean delivery results in reduced efficacy, yet as a secondary outcome was associated with reduced frequency of spinal-induced hypotension. Our primary aim was to investigate the relationship between hyperbaric bupivacaine dose and the occurrence of spinal-induced hypotension for cesarean delivery.

METHODS

Retrospective study of cesarean delivery under spinal or combined spinal anesthesia with hyperbaric bupivacaine in 1 academic institution (2 centers-tertiary and district) from 2012 to 2018. Data were retrieved from the anesthesia information management systems (Metavision, iMDsoft, Tel Aviv, Israel) and the hospital information system, including potential confounding factors, maternal age and weight, hypertensive disease of pregnancy, single/multiple gestation, gestational age, vasopressor administration, planned/urgent surgery, position during anesthesia placement (sitting/lateral), and anesthesiologist seniority. Spinal-induced hypotension was defined as systolic blood pressure that either dropped >20% from baseline or <100 mm Hg. The primary outcome of interest was the incidence of spinal-induced hypotension according to hyperbaric bupivacaine dose. Logistic regression was used to characterize the association between the dose of hyberbaric bupivacaine and spinal-induced hypotension after adjusting for confounding factors.

RESULTS

A total of 8226 women were identified. The hyperbaric bupivacaine dose administered was <9 mg for 2395 (29.1%), 9-9.5 mg for 1031 (12.5%), 10 mg for 4155 (50.5%), and >10 mg for 645 (7.8%). We used a cutoff (<10 vs ≥10 mg) to assess for the primary outcome, using multivariable logistic regression. The incidence of at least 1 spinal-induced hypotension episode was higher in patients who received ≥10 mg hyperbaric bupivacaine, 75.8% vs 62.9% for doses below 10 mg, P < .0001; however, even women with lower doses had hypotension. Hyperbaric bupivacaine dose <10 mg was associated with a lower incidence of spinal hypotension, adjusted odds ratio (OR) of 0.774, 95% confidence interval (CI), 0.669-0.897, and P = .0006, adjusted for confounding factors.Umbilical cord pH was available for 2684 (32.6%) cases. There were significantly more neonates with pH < 7.2, among women who received hyperbaric bupivacaine ≥10 mg (10.1%) versus women who received <10 mg (6.8%), P = .0032; however, in the adjusted model, hyperbaric bupivacaine dose ≥10 mg was not associated with pH < 7.2 and an OR of 0.955 (95% CI, 0.631-1.446, P = .829).

CONCLUSIONS

Our major finding was that hypotension occurred at all doses of hyperbaric bupivacaine, yet occurrence of spinal hypotension was significantly associated with doses ≥10 mg after adjustment for potential confounders.

Utilization of epidural volume extension technique for external cephalic version

External cephalic version (ECV) has been successfully utilized to reduce breech presentations at term and offers an alternative to elective cesarean delivery. Unfortunately, there is not a consensus on which type of regional anesthesia conveys the highest chances for a successful ECV. This case report describes the use of the epidural volume extension technique to provide surgical anesthesia for ECV with a reduced dose of local anesthetic, with the goals of minimizing motor block and hypotension in the setting of an outpatient procedure.

Fixed Dose versus Height-Adjusted Conventional Dose of Intrathecal Hyperbaric Bupivacaine for Caesarean Delivery: A Prospective, Double-Blinded Randomised Trial

The optimal intrathecal dose of local anaesthetic for caesarean section (CS) anaesthesia is still being debated. We performed a study to compare the effectiveness and safety of spinal anaesthesia with 12.5 mg of hyperbaric bupivacaine and a dosing regimen of conventional doses adjusted to parturient height. One hundred and forty parturients scheduled for elective CS were enrolled. The fixed-dose group (FD) received a spinal block with 12.5 mg of hyperbaric bupivacaine with fentanyl, whereas the adjusted-dose group (AD) received a height-adjusted dose of bupivacaine (9-13 mg) with fentanyl. Sensory block ≥ T5 dermatome within 10 min and no need for supplementary analgesia were set as the composite primary outcome (success). Rates of successful blocks and complications were compared. Complete data were available for 134 cases. Spinal anaesthesia was successful in 58 out of 67 patients in the FD group and 57 out of 67 in the AD group (p > 0.05). Eight spinals in each group failed to produce a block ≥ T5 in 10 min, and one patient in the FD group and two in the AD group required i.v. analgesics despite sensory block ≥ T5. No differences were noted in terms of hypotension, bradycardia and nausea between the FD and AD groups. Compared to the height-adjusted dose regimen based on conventional doses of hyperbaric bupivacaine, the fixed dose regimen of 12.5 mg was equally effective and did not increase the risk of spinal block-related complications.

Preoperative anxiety can cause convulsion and severe hypotension immediately after spinal anaesthesia for caesarean delivery: a case report

Preoperative anxiety in patients under spinal anaesthesia may cause serious complications. We report a case of combined transient convulsion and severe hypotension immediately after spinal anaesthesia for caesarean delivery in a patient who presented with severe preoperative anxiety. Our patient’s consciousness and blood pressure recovered normally without any sequelae. However, preoperative anxiety can induce such complications, particularly in patients under regional anaesthesia. Therefore, early detection and deliberate management for preoperative anxiety are required for the patient’s safety and satisfaction.

Low-dose spinal anesthesia for cesarean section to prevent spinal-induced hypotension

PURPOSE OF REVIEW

Low-dose combined spinal epidural (CSE) anesthesia is a common technique to anesthetize women for cesarean section. It is used to reduce the incidence of hypotension while providing excellent anesthetic conditions.

RECENT FINDINGS

Low spinal doses produce effective anesthesia but of limited duration. Therefore, an epidural catheter (and thus CSE) is required to guarantee pain-free surgery. Recent work confirmed that lower spinal doses can reduce significantly hypotension.

SUMMARY

Low-dose CSE is a valuable strategy to anesthetize pregnant women for cesarean section but requires attention and training.

Height-based dosing algorithm of bupivacaine in spinal anaesthesia for decreasing maternal hypotension in caesarean section without prophylactic fluid preloading and vasopressors: study protocol for a randomised controlled non-inferiority trial

INTRODUCTION

Effectively preventing or treating spinal-induced maternal hypotension is considered to be the Holy Grail of obstetric anaesthesia. Prophylactic fluid preloading and vasopressors decrease hypotension but may aggravate heart load, induce fetal acidosis or maternal bradycardia. Using low-dose local anaesthetic decreases hypotension but may cause insufficient anaesthesia. Whether there is a height-based dosing algorithm of local anaesthetic in spinal anaesthesia for caesarean section that can provide sufficient anaesthesia with less hypotension without prophylactic fluid preloading and vasopressors is unclear. This study was designed to investigate a height-based dosing algorithm of bupivacaine in spinal anaesthesia for caesarean section.

METHODS AND ANALYSIS

This single-centre, double-blinded, prospective, non-inferiority, randomised controlled trial will include 264 parturients (between 18 and 45 years of age) who are scheduled for caesarean section. All participants will not receive prophylactic fluid preloading. The participants will be randomly divided into two groups: the test group or conventional group. For parturients in the test group, 0.5% isobaric bupivacaine (1.15-1.70 mL) will be injected into the subarachnoid space without prophylactic vasopressors. The bupivacaine dose depends on the height of subjects. For parturients in the conventional group, 0.5% bupivacaine (1.8 mL) will be injected into the subarachnoid space along with prophylactic vasopressors. The primary outcome is the incidence of maternal hypotension. The secondary outcomes include the failure rate of spinal anaesthesia, level of sensory block, degree of motor block, other complications in parturients, time of operation, neonatal outcome and quality of anaesthesia.

ETHICS AND DISSEMINATION

This study was approved by the Ethics Committee of Shenzhen People's Hospital of Jinan University (Permit No. SZY-00251, chairperson Xiaofang Yu) on 8 February 2018The study results will be disseminated through peer-reviewed journals, professional societies and meetings.

TRIAL REGISTRATION NUMBER

NCT03497364; Pre-results.

How Low Can We Go? A Double-Blinded Randomized Controlled Trial to Compare Bupivacaine 5 mg and Bupivacaine 7.5 mg for Spinal Anesthesia in Cesarean Delivery in Indonesian Population

Background

Maternal hypotension in cesarean delivery related to spinal anesthesia results in increasing morbidity of both mothers and children. Studies show that low dose spinal anesthesia was able to prevent hypotension while providing adequate analgesia. However, the dose used in those studies varies and this leaves the debate of the dose scheme of spinal anesthesia open.

Objectives

This study aimed to compare the effectiveness of 5 mg hyperbaric bupivacaine 0.5% and 25 mcg of fentanyl with 7.5 mg hyperbaric bupivacaine 0.5% and 25 mcg of fentanyl to prevent hypotension in spinal anesthesia for cesarean delivery.

Methods

This study was a double-blinded randomized controlled trial of 112 mothers undergoing cesarean delivery with spinal anesthesia. The intervention group received 5 mg bupivacaine and 25 mcg fentanyl. The comparison group received of 7.5 mg bupivacaine and 25 mcg fentanyl. The primary outcome was the incidence of hypotension. The adequacy of anesthesia, duration of recovery from the motoric block, the quality of analgesia as perceived by patients and surgeons, and the side effects of anesthesia were also recorded.

Results

There was no difference of effectiveness to prevent hypotension in both groups. The 7.5 mg dose provided better adequacy of anesthesia as reflected in lower incidence of conversion into general anesthesia. More surgeons reported adequacy of relaxation in the 7.5 mg dose. The 5 mg dose offered faster motoric recovery and fewer side effects.

Conclusions

The dose of 7.5 mg hyperbaric bupivacaine 0.5% and 25 mcg of fentanyl can be used as a prevention measure against hypotension due to spinal anesthesia cesarean delivery.

Hemodynamic effects of low-dose bupivacaine spinal anesthesia for cesarean section: A randomized controlled trial

Background

Spinal anesthesia is the most common technique for cesarean section. The conventional local anesthetic dose has been decreasing over time to 8-12.5 mg of bupivacaine. Lower doses of bupivacaine may be associated with reduced incidence of hypotension and other complications. This low dose also may be associated with improved maternal cardiac index (CI). We hypothesized that low dose spinal anesthesia using 4.5 mg bupivacaine would result in improved maternal CI when compared with conventional dose (9 mg) intrathecal bupivacaine.

Methods

This randomized controlled trial included all healthy parturients presenting for elective cesarean section. In addition to standard monitors, an arterial line was placed for pulse contour cardiac output measurement. Due to limited data on maternal cardiac output during cesarean section, we had to power our study on recovery room length of stay. Secondary outcomes included the change in maternal CI, fluid administration, vasopressor usage, maternal satisfaction, and adequacy of surgical blockade and recovery time from motor and sensory blockade.

Results

The low dose group had significantly faster motor recovery times (132 [122-144] versus. 54 [48-66] min conventional versus. low-dose, respectively, P < 0.01), and a shorter recovery room stay (92 ± 21 vs 70 ± 11 min, conventional vs. low-dose, respectively, P < 0.01, 95% CI -35 to -10 min). There was no difference in CI between the conventional dose and low dose spinal groups. Both groups had a drop in CI with spinal anesthesia. The low-dose group demonstrated equivalent surgical anesthesia and block onset times compared to the conventional group.

Conclusions

Low-dose spinal anesthesia provides adequate surgical anesthesia, improved recovery time, but no difference in maternal cardiac index when compared to conventional dose spinal anesthesia.NCT02046697.

Efficacy of low dose bupivacaine with intrathecal fentanyl for cesarean section on maternal hemodynamic: Systemic review and meta-analysis

Hypotension during spinal Anesthesia is the most common complication with maternal and neonatal morbidity and mortality. Low dose bupivacaine with intrathecal fentanyl is recommended as strategy to prevent spinal Anesthesia induced hypotension and related complications. The aim of this systemic review is to evaluate the efficacy of low dose bupivacaine with Intrathecal fentanyl on the improvement of maternal and neonatal outcomes compared to conventional dose bupivacaine among mothers who undergone cesarean section. We conducted a systemic search of the electronic databases of Pubmed, Medline, LILACS and others with PICO strategy for randomized controlled clinical trials comparing low dose bupivacaine with fentanyl and conventional dose bupivacaine for cesarean section. Joanna Briggs Institute (JBI) standardized data extraction form was used for data extraction and finally entered into Review Manager for data synthesis. Ten Randomized trials (552) were included in this review. Incidence of hypotension was less likely in mothers who received low dose bupivacaine with Fentanyl as compared to those with conventional dose of bupivacaine alone (RR = 0.43, 95% confidence interval (CI) 0.12-0.47, ten trials, 552 participants). The review revealed that Low dose bupivacaine combined with intrathecal Fentanyl decrease incidence of hypotension.

Large dose bupivacaine 0.5% versus small dose in elective cesarean section

Background and Aim:

The spinal anesthesia in a cesarean section is still presenting a challenge to the anesthetist in the form of either severe hypotension from large bupivacaine dose or insufficient satisfactory anesthesia level conditions as a result of small bupivacaine dose. In this study, we tried to solve this challenge by increasing the dose of bupivacaine to achieve a proper spinal level accompanied by prolonged sitting up to avoid hypotension.

Patients and Methods:

We included 53 patients in this study whom were randomly divided into two groups, namely Group B and Group C. In Group B (25 patients), each patient received 3 mL of bupivacaine and left 5 min sitting up, whereas in Group C (28 patients), each patient received 2.5 mL of bupivacaine and was asked to lie supine immediately. Both groups were tested for hypotension, ephedrine dose, and sensory block level.

Results:

The present study showed a statistically significant lower dose of ephedrine which was given in Group B (7.2 ± 15.684 mg in Group B versus 27.86 ± 12.04 mg in Group C with P < 0.05). The proper anesthesia level was achieved equally in both groups.

Conclusions:

Large dose 15 mg of bupivacaine with the prolonged sitting position will lead to fewer incidences of hypotension and proper anesthesia block.

Anesthetic considerations for cesarean section in a parturient complicated by Scimitar syndrome-like pathophysiology

Background

Pre-existing poor respiratory function is a significant challenge for women to successfully continue pregnancy and accomplish delivery.

Case

Pregnancy and delivery were successfully managed without any maternal or neonatal complications, in a 26-year-old woman with severely impaired respiratory function, due to a unilateral hypoplastic lung, accompanying Scimitar syndrome-like circulation. Hyperventilation, normally observed even at the first trimester, was absent by the end of the second trimester. This would indicate her ventilation must have reached utmost capacity. Premature delivery by the mode of elective cesarean section delivery was, therefore, the most reasonable option. General anesthesia, combined with a continuous epidural infusion of low-concentrate local anesthetics, containing opioid, was sufficient to avoid the need for unexpected mechanical ventilation in intra- and early postoperative periods and to provide excellent post-partum analgesia.

Conclusion

This combination can be a potent alternative in tailoring anesthesia for cesarean section in women with extremely impaired pulmonary reserve.

Relationship Between Body Mass Index and Spread of Spinal Anesthsia in Pregnant Women: A Randomized Controlled Trial

BACKGROUND The effect of body mass index (BMI) on the spread of spinal anesthesia is not completely clear. The aim of this study was to determine the dose requirements of ropivacaine and the incidence of hypotension in pregnant women with different BMIs during cesarean delivery. MATERIAL AND METHODS In this double-blind study, 405 women undergoing elective cesarean delivery were allocated to group S (BMI <25), group M (25 ≤BMI <30), or group L (BMI ≥30). Women in each group were further assigned to receive 7, 8, 9, 10, 11, 12, 13, 14, or 15 mg of spinal ropivacaine. RESULTS The ED50 and ED95 values of ropivacaine were 9.487 mg and 13.239 mg in Group S, 9.984 mg and 13.737 mg in Group M, and 9.067 mg and 12.819 mg in Group L. There were no significant differences among the 3 groups (p=0.915). Group L had a higher incidence of hypotension and a greater change in MAP after spinal anesthesia compared to the other 2 groups, and also required more doses of ephedrine than the other 2 groups when a dose of 15 mg ropivacaine was used. The incidence of hypotension had a positive correlation with the dose of ropivacaine (OR=1.453, p<0.001) and gestational age (OR=1.894, p<0.001). CONCLUSIONS Spinal ropivacaine dose requirements were similar in the normal BMI range. However, higher doses of spinal ropivacaine were associated with an increased incidence and severity of hypotension in obese patients compared with that in non-obese patients.

The effect of intrathecal dexmedetomidine on the dose requirement of hyperbaric bupivacaine in spinal anaesthesia for caesarean section: a prospective, double-blinded, randomized study

Background

Studies have shown that dexmedetomidine (Dex) can prolong the duration of analgesia when added to local anaesthetic as an adjuvant in a central or peripheral nerve block. We hypothesized that intrathecal Dex can reduce the ED95 of spinal hyperbaric bupivacaine. Therefore, we conducted this prospective, double-blinded, randomized study to verify our hypothesis.

Methods

Ninety patients were allocated into the Dexmedetomidine group (received bupivacaine + 5 mcg dexmedetomidine) and the Control group (received bupivacaine + the same volume of saline) using a double-blinded and randomized method. The first patient in each group received 5 mg of IT hyperbaric bupivacaine, and the next dose for the following patient was determined by the probability of successful anaesthesia of the previous neighbouring dose. An improved up-down sequence allocated method combined with probit analysis was used to determine the ED95 of intrathecal hyperbaric bupivacaine for the two groups.

Results

The ED95 and 95% confidence intervals (95% CI) of IT hyperbaric bupivacaine of the Dex group and Control group were 8.4 mg (95% CI, 6.5~ 13.8 mg) and 12.1 mg (95% CI, 8.3~ 312.8 mg), respectively. The duration of sensory block was longer in the Dex group than in the Control group (110.3 ± 35.3 vs 67.5 ± 26.2). The duration of analgesia was also longer in the Dex group than in the Control group (224.9 ± 45.4 vs 155.1 ± 31.6). The consumption of postoperative rescued sufentanil was significantly higher in the Control group than in the Dex group.

Conclusion

Intrathecal 5 mcg dexmedetomidine potentiated hyperbaric bupivacaine antinociception by 31% in spinal anaesthesia for patients undergoing caesarean section.

Trial registration

We registered this study in a Chinese Clinical Trial Registry (ChiCTR) centre on Nov 1st 2016 and received the registration number: ChiCTR-IPR-16009699.

Combined spinal-epidural vs. spinal anaesthesia for caesarean section: meta-analysis and trial-sequential analysis

Combined spinal-epidural and single-shot spinal anaesthesia are both used for caesarean section. It has been claimed in individual trials that combined spinal-epidural is associated with higher sensory spread and greater cardiovascular stability. We set out to gather all available evidence. We performed: a systematic literature search to identify randomised controlled trials comparing combined spinal-epidural with spinal anaesthesia for caesarean section: conventional meta-analysis; trial-sequential analysis; and assessment of trial quality using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system. Fifteen trials with high heterogeneity, including 1015 patients, were analysed. There was no significant difference between combined spinal-epidural and spinal anaesthesia for our primary outcomes maximum sensory height and vasopressor use (mg ephedrine equivalents). However, trial-sequential analysis suggested insufficient data and the GRADE scores showed 'very low' quality of evidence for these outcomes. The secondary outcomes hypotension, time for sensory block to recede to the level of T10, and the combined outcome of nausea and vomiting, did not differ significantly between the interventions. The block times were statistically significantly longer for combined spinal-epidural in individual trials, but only one trial showed a clinically meaningful difference (11 min). Based on this analysis, and taking into consideration all comparisons irrespective of whether drugs had been applied via the epidural route, there is not enough evidence to postulate any advantage compared with the spinal technique. Future analyses and studies need to examine the potential advantages of the combined spinal-epidural technique by using the epidural route intra- and/or postoperatively.

Effective Loading Dose of Dexmedetomidine to Induce Adequate Sedation in Parturients Undergoing Caesarean Section Under Spinal Anaesthesia

Objective

To calculate the effective dose (ED) of dexmedetomidine for caesarean section under spinal anaesthesia.

Methods

Consecutive parturients scheduled for caesarean section under spinal anaesthesia were included. The loading dose of dexmedetomidine was evaluated using the up-and-down method, starting at 1.0 μg kg^-1 and a step size of 0.1 μg kg^-1. The loading dexmedetomidine was administrated by the venous route for 10 min, and afterwards a maintenance dose began at a rate of 0.3 μg kg^-1 h^-1 in all parturients. Adequate sedation was defined as a Ramsay sedation score ≥3. The ED50 and ED95 of loading dexmedetomidine were calculated using probit regression.

Results

The ED50 and ED95 of loading dexmedetomidine for adequate sedation were 0.82 μg kg^-1 (95% confidence intervals [CI] 0.73-0.89 μg kg^-1) and 0.96 μg kg^-1 (95% CI 0.90-1.39 μg kg^-1), respectively.

Conclusion

The ED50 and ED95 of loading dexmedetomidine to achieve adequate sedation were 0.82 μg kg^-1 and 0.96 μg kg^-1 for caesarean section under spinal anaesthesia.