The Effect of Intrathecal Meperidine on Maternal and Newborn Outcomes After Cesarean Section: A Systematic Review and Meta-Analysis Study

The effect of adding dexmedetomidine or dexamethasone to bupivacaine-fentanyl mixture in spinal anesthesia for cesarean section

Background and Aims

Many strategies are available to prevent spinal-induced hypotension in cesarean section, especially the use of a low dose of spinal anesthesia combined with adjuvants. This study investigated the effect of adding either dexmedetomidine or dexamethasone to the intrathecal bupivacaine-fentanyl mixture on the postoperative analgesia duration, after elective cesarean section.

Material and Methods

This prospective, randomized, double-blind study was conducted on 90 full-term parturients undergoing elective cesarean section, who were randomly distributed into three groups. They all received spinal anesthesia with the bupivacaine-fentanyl mixture (2.5 ml), in addition to 0.5 ml normal saline (control group), 5 μg dexmedetomidine dissolved in 0.5 ml normal saline (dexmedetomidine group), or 2 mg dexamethasone (dexamethasone group). The time to the first request of morphine rescue analgesia was recorded, in addition to the total dose of morphine consumed in the first 24 h after surgery, the postoperative numerical rating score (NRS), and maternal and fetal outcomes.

Results

As compared to the control group and the dexamethasone group, the use of dexmedetomidine as an additive to the bupivacaine-fentanyl mixture significantly prolonged the time to the first request of rescue analgesia, decreased postoperative morphine consumption, and decreased the pain score 4 and 6 h after surgery. There was an insignificant difference between the control and dexamethasone groups.

Conclusion

The use of dexmedetomidine as an additive to bupivacaine-fentanyl mixture in spinal anesthesia for cesarean section prolonged the postoperative analgesia and decreased the postoperative opioid consumption in comparison to the addition of dexamethasone or normal saline.

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.

Efficacy and safety of wound infiltration modalities for postoperative pain management after cesarean section: a systematic review and network meta-analysis protocol

BACKGROUND

Postoperative pain after a cesarean section has negative consequences for the mother during the postoperative period. Over the years, various postoperative pain management strategies have been used following cesarean section. Opioid-based analgesics and landmark approaches have negative side effects, while ultrasound-based regional analgesia necessitates resources and experience, but various wound infiltration adjuvants are innovative with few side effects and are simple to use. The efficacy and safety of each adjuvant, however, are unknown and require further investigation.

OBJECTIVE

This network meta-analysis is intended to provide the most effective wound infiltration drugs for postoperative management after cesarean section.

METHOD

A comprehensive search will be conducted in PubMed/MEDLINE, Cochrane Library, Science Direct, CINHAL, and LILACS without date and language restrictions. All randomized trials comparing the effectiveness of wound infiltration drugs for postoperative pain management after cesarean section will be included. Data extraction will be conducted independently by two authors. The quality of studies will be evaluated using the Cochrane risk of bias tool, and the overall quality of the evidence will be determined by GRADEpro software.

DISCUSSION

The rate of postoperative acute and chronic pain is very high which has a huge impact on the mother, family, healthcare practitioners, and healthcare delivery. It is a basic human right to give every patient with postoperative pain treatment that is realistic in terms of resources, technique, cost, and adverse event profile.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42021268774.

The Effect of Intrathecal Injection of Dextromethorphan on the Experimental Neuropathic Pain Model

Background

Peripheral glucocorticoid receptors (GRs) are altered by peripheral nerve injury and may modulate the development of neuropathic pain. Two central pathogenic mechanisms underlying neuropathic pain are neuroinflammation and N-methyl-D-aspartate receptor (NMDAR)-dependent neural plasticity in the spinal cord.

Objectives

This study examined the effect of the non-competitive NMDAR antagonist dextromethorphan on partial sciatic nerve ligation (PSL)-induced neuropathic pain and the spinal expression of the glucocorticoid receptor (GR).

Methods

Male mice were randomly assigned into a sham group and two groups receiving PSL followed by intrathecal saline vehicle or dextromethorphan (iDMP). Vehicle or iDMP was administered 8 - 14 days after PSL. The hotplate paw-withdrawal latency was considered to measure thermal pain sensitivity. The spinal cord was then sectioned and immunostained for GR.

Results

Thermal hyperalgesia developed similarly in the vehicle and iDMP groups prior to the injections (P = 0.828 and 0.643); however, it was completely mitigated during the iDMP treatment (P < 0.001). GR expression was significantly higher in the vehicle group (55.64 ± 4.50) than in the other groups (P < 0.001). The iDMP group (9.99 ± 0.66) showed significantly higher GR expression than the sham group (6.30 ± 1.96) (P = 0.043).

Conclusions

The suppression of PLS-induced thermal hyperalgesia by iDMP is associated with the downregulation of GR in the spinal cord, suggesting that this analgesic effect is mediated by inhibiting GR-regulated neuroinflammation.

Full Opioid Agonists and Tramadol: Pharmacological and Clinical Considerations

Opioids are mu receptor agonists and have been an important part of pain treatment for thousands of years. In order to use these drugs appropriately and successfully in patients, whether to control pain, to treat opiate-induced side effects, or opiate withdrawal syndromes, a solid understanding of the pharmacology of such drugs is crucial. The most recognized full agonist opioids are heroin, morphine, codeine, oxycodone, meperidine, and fentanyl. Phenanthrenes refer to a naturally occurring plant-based compound that includes three or more fused rings. The opioids derived from the opium plant are phenanthrene derivatives, whereas most synthetic opioids are simpler molecules that do not have multiple rings. Methadone acts as a synthetic opioid analgesic similar to morphine in both quality and quantity; however, methadone lasts longer and in oral form, has higher efficacy, and is considered a diphenylheptane. Fentanyl is a strong synthetic phenylpiperdine derivative that exhibits activity as a mu-selective opioid agonist approximately 50 to 100 times more potent than morphine. Meperidine is another medication which is a phenylpiperdine. Tramadol is considered a mixed-mechanism opioid drug, as it is a centrally acting analgesic that exerts its effects via binding mu receptors and blocking the reuptake of monoamines. Some of the most common adverse effects shared among all opioids are nausea, vomiting, pruritus, addiction, respiratory depression, constipation, sphincter of Oddi spasm, and miosis (except in the case of meperidine). Chronic opioid usage has also established a relationship to opioid-induced hypogonadism and adrenal suppression. Physicians must be stewards of opioid use and use opioids only when necessary.

Effects of colloid preload on the incidence of hypotension in spinal anesthesia for cesarean section: a systematic review and meta-analysis

Background:

Hypotension is a common complication caused by spinal anesthesia (SA), which may have adverse impacts on the condition of the parturient and fetus. Liquid infusion was found to be relatively effective for reducing the incidence of hypotension. However, the question of whether colloid preload can optimize hemodynamic variables in the cesarean section remains controversial. This study aims to determine the effects of colloid preload on the incidence of hypotension induced by SA in elective cesarean section.

Methods:

Related keywords were searched on PubMed, EMBASE, and Cochrane Library from inception dates to May 2020. Studies included were evaluated for eligibility and quality. The primary outcome was the intra-operative incidence of hypotension and severe hypotension. The secondary outcomes included the lowest intra-operative systolic blood pressure, the maximal intra-operative heart rate, the intra-operative needs of ephedrine and phenylephrine, the incidence of maternal nausea and/or vomiting, and neonatal outcomes (umbilical artery pH and Apgar scores). Apart from the above, RevMan 5.3 was used for the data analysis.

Results:

Altogether nine randomized controlled trials were included in the meta-analysis. There were no significant differences in the incidence of intra-operative hypotension, severe hypotension, or neonatal outcomes between the colloid preload group and control group, except for the umbilical artery pH.

Conclusion:

This meta-analysis suggests that colloid preload does not significantly reduce the incidence of hypotension associated with SA in elective cesarean section.

Comparative Study of Effect of Spinal Anesthesia in Sitting and Lateral Positions on the Onset Time of Sensory Block and Hemodynamic Condition in Cesarean Section: A Randomized Clinical Trial

BACKGROUND

Spinal anesthesia is the method of choice for the cesarean section. Hypotension is a common complication of this method.

OBJECTIVES

This study aimed to compare the effect of spinal anesthesia in the sitting and lateral positions on the onset time of sensory block and hemodynamic condition in cesarean sections.

METHODS

In this clinical trial, 106 elective cesarean section candidates under spinal anesthesia were selected and randomly divided into two groups: spinal anesthesia in the sitting position (group S) and the lateral position (group L). The onset time of the sensory block, quality of sensory and motor block, hemodynamic condition, frequency of hypotension, nausea, and vomiting, and the doses of ephedrine and atropine were compared between both groups. Data were analyzed with SPSS version 16 software at a 95% confidence level.

RESULTS

There was no statistically significant difference between the two groups in terms of age. The frequency of hypotension in L and S groups was 24.5% and 57.7%, respectively (P = 0.001), in minute 6 after spinal anesthesia and 5.7% and 36.5%, respectively (P < 0.001), in minute 8 after spinal anesthesia. The mean time to reach the sensory level of T6 was 1.30 ± 0.43 min versus 4.54 ± 2.12 min (P < 0.001), motor block score in minute 5 was 2.98 ± 0.14 versus 2.82 (P = 0.044), and ephedrine dose was 11.5 mg and 16.92 mg in the L and S groups, respectively (P = 0.010). The maximum sensory-motor block and satisfaction of women with spinal anesthesia were significantly higher in the lateral position than in the sitting position (P < 0.05).

CONCLUSIONS

Cesarean sections under spinal anesthesia in the lateral position than in the sitting position lead to a more rapid sensory and motor block, reduced ephedrine consumption, and enhanced satisfaction of women.

Successful Management of a Suspected Case of Meperidine-Induced Anaphylaxis in Cesarean Delivery

Introduction

Meperidine is known as the gold standard drug for shivering after spinal anesthesia (SA). This drug has been used widely and safely during the Cesarean Section (CS).

Case Presentation

This case report presents an anaphylaxis reaction to a single intravenous dose of 25 mg meperidine, aiming to control shivering during CS under SA a few minutes after surgical incision.

Conclusions

The condition was well managed with timely intervention. This rare fetal reaction to meperidine is worthy of reporting to make the medical team aware of the potential risks of anaphylaxis due to many routine safe drugs.