Intrathecal morphine versus epidural ropivacaine infusion for analgesia after Cesarean section: a retrospective study

Efficacy and Safety of Intrathecal Morphine for Cesarean Delivery: A Narrative Review

PURPOSE OF REVIEW

Pain management is a critical aspect of care during and following a cesarean delivery. Without proper control of pain, individuals can experience poor mobility, increased thromboembolic events, and difficulty caring for the neonate in the postpartum period. There have been multiple methods for pain management for cesarean delivery and intrathecal morphine (ITM) has emerged as a prominent option for post-operative analgesia due to its efficacy, safety, and potential benefits over other treatments. This review analyzes data on efficacy, side effects, and safety of ITM and the pain control alternatives.

RECENT FINDINGS

A comprehensive literature review was conducted to compare ITM with other analgesic techniques in post-cesarean patients. ITM was found to be as effective or better than other analgesic options, including bilateral quadratus lumborum block (QLB), opioid-free epidural analgesia (CSEA-EDA), and intravenous fentanyl. One study found that both ITM and oral analgesia were effective in pain control and that ITM caused fewer breakthrough pain events but had a longer duration and a greater rate of side effects than oral opioid analgesia. Commonly observed side effects of intrathecal opioids include nausea, vomiting, pruritus, and urinary retention, and it is thought that the adverse effects from intrathecal administration of opioids are short-lived. ITM may provide a decreased risk of DVT and coagulation by decreasing lower extremity weakness and numbness, thereby decreasing recovery time and increasing mobility. ITM is a safe and effective option for post-cesarean analgesia, with comparable pain relief to alternative forms of pain control, and side effects that are generally manageable. Further research is warranted to explore beneficial combinations with other methods of pain management and optimal dosing strategies.

Analgesia after cesarean section - what is new?

PURPOSE OF REVIEW

Cesarean section is the most frequent surgical intervention, and pain following cesarean delivery unfortunately remains a common issue. The purpose of this article is to highlight the most effective and efficient options for postcesarean analgesia and to summarize current guidelines.

RECENT FINDINGS

The most effective form of postoperative analgesia is through neuraxial morphine. With adequate dosing, clinically relevant respiratory depression is extremely rare. It is important to identify women with increased risk of respiratory depression, as they might require more intensive postoperative monitoring. If neuraxial morphine cannot be used, abdominal wall block or surgical wound infiltration are very valuable alternatives. A multimodal regimen with intraoperative intravenous dexamethasone, fixed doses of paracetamol/acetaminophen, and nonsteroidal anti-inflammatory drugs reduce postcesarean opioid use. As the use of postoperative lumbar epidural analgesia impairs mobilization, double epidural catheters with lower thoracic epidural analgesia are a possible alternative.

SUMMARY

Adequate analgesia following cesarean delivery is still underused. Simple measures, such as multimodal analgesia regimens should be standardized according to institutional circumstances and defined as part of a treatment plan. Neuraxial morphine should be used whenever possible. If it cannot be used, abdominal wall blocks or surgical wound infiltration are good alternatives.

Efficacy and safety of different doses of epidural morphine coadministered with low-concentration ropivacaine after cesarean section: A retrospective cohort study

Objective: The optimal dose of epidural morphine after cesarean section (CS) still remains unknown when combined with low-concentration ropivacaine based on a continuous basal infusion (CBI) mode. The aim of this study was to assess the impact of different dose of epidural morphine plus ropivacaine on maternal outcomes.

Materials and methods: Data of parturients who received epidural analgesia for CS at a teaching hospital from March 2021 to June 2022 were retrospectively collected. Parturients were divided into two groups (RM3 group and RM6 group) according to different medication regimens of morphine. The implementation of epidural analgesia was performed with 3 mg morphine in RM3 group and 6 mg morphine in RM6 group in combination with 0.1% ropivacaine via a CBI pump. The primary outcomes included pain intensity at rest and movement and the incidence of urinary retention and pruritus within postoperative 48 h. The secondary outcomes included the incidence and severity of postoperative nausea and vomiting (PONV) and pruritus, the rate of rescue analgesia and grading of motor Block.

Results: Totally, 531 parturients were eligible for the final analysis, with 428 and 103 parturients in the RM3 group and RM6 group, respectively. There were no statistically significant differences in the visual analogue scores (VAS) at rest and movement within postoperative 48 h between the two groups (all p > 0.05). Compared with the RM6 group, the incidence of urinary retention was lower in the RM3 group within 48 h after CS (4.0% vs. 8.7%, p = 0.044). No significant difference was found in the incidence and severity of PONV and pruritus, the rate of rescue analgesia and grading of motor block between RM3 and RM6 groups.

Conclusion: Epidural 3 mg morphine plus 0.1% ropivacaine in a CBI mode can provide equal efficacy and have lower incidence of urinary retention compared with 6 mg morphine after CS.

Anterior Quadratus Lumborum Block at the Lateral Supra-Arcuate Ligament versus Transmuscular Quadratus Lumborum Block for Analgesia after Elective Cesarean Section: A Randomized Controlled Trial

Several studies have shown the effectiveness of trans-muscular quadratus lumborum block (TQLB) in analgesia after cesarean delivery. However, the influence of anterior QLB at the lateral supra-arcuate ligament (QLB-LSAL) in this surgery is unclear. This study aimed to compare the analgesic efficacy of bilateral TQLBs with bilateral QLBs-LSAL following cesarean delivery. Ninety-four parturients scheduled for cesarean delivery under spinal anesthesia were enrolled and randomly allocated to undergo either bilateral TQLBs or bilateral QLBs-LSAL with 0.375% of ropivacaine (20 mL each side) following cesarean delivery. Intravenous sufentanil was administered for patient-controlled analgesia (PCA). The primary outcome was postoperative sufentanil consumption during the initial 24 h post-surgery. Secondary endpoints included pain scores, time to the first PCA request, postoperative rescue analgesia, satisfaction scores, and nausea/vomiting events. Sufentanil consumption was significantly reduced in the QLB-LSAL group in the first 24 h compared with the TQLB group after surgery (29.4 ± 5.7 μg vs. 39.4 ± 9.6 μg, p < 0.001). In comparison with TQLB, the time to the first PCA request in the QLB-LSAL group was significantly longer (10.9 ± 4.1 h vs. 6.7 ± 1.8 h, p < 0.001). No differences were observed between two groups regarding pain scores, rescue analgesia after surgery, satisfaction scores, or nausea/vomiting incidence. The significant reduction in opioid consumption in the first 24 h and prolongation in time to first opioid demand in parturients receiving QLB-LSAL compared with TQLB suggest that the QLB-LSAL is a superior choice for multimodal analgesia after cesarean delivery.

An optimal epidural catheter placement site for post-cesarean section analgesia with double-space technique combined spinal-epidural anesthesia: a retrospective study

Background

Epidural anesthesia affects lower extremities, which often prevents early mobilization postoperatively. The incidence of numbness and motor weakness in the lower extremities with respect to epidural catheter placement site in cesarean section (CS) is uncertain. We aimed to investigate the effect of catheter placement site on postoperative lower extremities numbness and motor weakness in patients who received combined spinal–epidural anesthesia (CSEA) for CS including analgesic effects and optimal epidural placement site in CS.

Methods

We retrospectively included 205 patients who underwent CS with CSEA at the University of Tsukuba Hospital between April 2018 and March 2020, and assessed numbness and motor weakness in the lower extremities. We also examined whether differences in the intervertebral space of epidural catheter placement and epidural effect on the lower extremities are related to analgesic effects. ANOVA and Mann–Whitney U test were used for statistical analysis.

Results

The incidence of numbness and motor weakness were 67 (33%) and 28 (14%), respectively. All patients with motor weakness had numbness. A more caudal placement was associated with increased incidence of affected lower extremities. There was no significant difference in the analgesic effect depending on the catheter placement site. When the lower extremities were affected, the number of additional analgesics increased (p < 0.001). Patient-controlled epidural analgesia was used for fewer days in patients with motor weakness (p = 0.046).

Conclusion

In CS, epidural catheter placement at T10–11 or T11–12 interspace is expected to reduce effect on the lower extremities and improve quality of postoperative analgesia.

Comparison of intrathecal morphine with continuous patient-controlled epidural anesthesia versus intrathecal morphine alone for post-cesarean section analgesia: a randomized controlled trial

Background

Several neuraxial techniques have demonstrated effective post-cesarean section analgesia. According to previous reports, it is likely that patient-controlled epidural analgesia (PCEA) without opioids is inferior to intrathecal morphine (IM) alone for post-cesarean section analgesia. However, little is known whether adding PCEA to IM is effective or not. The aim of this study was to compare post-cesarean section analgesia between IM with PCEA and IM alone.

Methods

Fifty patients undergoing elective cesarean section were enrolled in this prospective randomized study. Patients were randomized to one of two groups: IM group and IM + PCEA group. All patients received spinal anesthesia with 12 mg of 0.5% hyperbaric bupivacaine, 10 μg of fentanyl, and 150 μg of morphine. Patients in IM + PCEA group received epidural catheterization through Th11–12 or Th12-L1 before spinal anesthesia and PCEA (basal 0.167% levobupivacaine infusion rate of 6 mL/h, bolus dose of 3 mL in lockout interval of 30 min) was commenced at the end of surgery. A numerical rating scale (NRS) at rest and on movement at 4,8,12,24,48 h after the intrathecal administration of morphine were recorded. In addition, we recorded the incidence of delayed ambulation and the number of patients who requested rescue analgesics. We examined NRS using Bonferroni’s multiple comparison test following repeated measures analysis of variance; p < 0.05 was considered as statistically significant.

Results

Twenty-three patients in each group were finally analyzed. Mean NRS at rest was significantly higher in IM group than in IM + PCEA group at 4 (2.7 vs 0.6), 8 (2.2 vs 0.6), and 12 h (2.5 vs 0.7), and NRS during mobilization was significantly higher in IM group than in IM + PCEA group at 4 (4.9 vs 1.5), 8 (4.8 vs 1.9), 12 (4.9 vs 2), and 24 h (5.7 vs 3.5). The number of patients who required rescue analgesics during the first 24 h was significantly higher in IM group compared to IM + PCEA group. No significant difference was observed between the groups in incidence of delayed ambulation.

Conclusions

The combined use of PCEA with IM provided better post-cesarean section analgesia compared to IM alone.

Trial registration

UMIN-CTR (Registration No. UMIN000032475). Registered 6 May 2018 – Retrospectively registered.

Neuraxial opioids as analgesia in labour, caesarean section and hysterectomy: A questionnaire survey in Sweden

Background: Neuraxial opioids improve labour analgesia and analgesia after caesarean section (CS) and hysterectomy. Undesirable side effects and difficulties in arranging postoperative monitoring might influence the use of these opioids. The aim of the present survey was to assess the use of intrathecal and epidural morphine in gynaecology and obstetrics in Sweden. Methods: A questionnaire was sent to all anaesthetic obstetric units in Sweden concerning the use and postoperative monitoring of morphine, sufentanil and fentanyl in spinal/epidural anaesthesia. Results: A total of 32 of 47 (68%) units responded representing 83% of annual CS in Sweden. In CS spinal anaesthesia, 20/32 units use intrathecal morphine, the most common dose of which was 100 μg (17/21). Intrathecal fentanyl (10-20 μg) was used by 21 units and sufentanil (2.5 -10 μg) by 9/32 of the responding units. In CS epidural anaesthesia, epidural fentanyl (50-100 μg) or sufentanil (5-25 μg) were commonly used (25/32), and 12/32 clinics used epidural morphine, the majority of units used a 2 mg dose. Intrathecal morphine for hysterectomy was used by 20/30 units, with 200 μg as the most common dose (9/32). Postoperative monitoring was organized in adherence to the National Guidelines; the patient is monitored postoperative care or an obstetrical ward over 2-6 hours and up-to 12 hours in an ordinary surgical ward. Risk of respiratory depression/difficult to monitor was a reason for not using intrathecal opioids. Conclusions: Neuraxial morphine is used widely in Sweden in CS and hysterectomy, but is still restricted in some units because of the concern for respiratory depression and difficulties in monitoring.