Opioid use after cesarean: a cohort study comparing combined versus separate oxycodone and acetaminophen regimens

Endogenous opiates and behavior: 2022

This paper is the forty-fifth consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2022 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonists and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (1), the roles of these opioid peptides and receptors in pain and analgesia in animals (2) and humans (3), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (4), opioid peptide and receptor involvement in tolerance and dependence (5), stress and social status (6), learning and memory (7), eating and drinking (8), drug abuse and alcohol (9), sexual activity and hormones, pregnancy, development and endocrinology (10), mental illness and mood (11), seizures and neurologic disorders (12), electrical-related activity and neurophysiology (13), general activity and locomotion (14), gastrointestinal, renal and hepatic functions (15), cardiovascular responses (16), respiration and thermoregulation (17), and immunological responses (18).

Enhanced recovery for cesarean delivery leads to no difference in length of stay, decreased opioid use and lower infection rates

OBJECTIVE

The primary objective of this study was to report surgical outcomes for cesarean delivery (CD) patients following the implementation of an Enhanced Recovery after Surgery (ERAS) pathway based on the ERAS Society recommendations. The primary outcome for which the study was powered was the length of stay (LOS).

METHODS

This IRB-approved cohort study was conducted at a single tertiary-care labor and delivery unit and utilized a pre-post intervention design. Our ERAS for CD protocol was designed using the ERAS Society recommendations and implemented globally for every patient admitted to the labor and delivery unit including both scheduled and unscheduled cases. The study was designed to have at least 85% power to detect a 6-h difference in length of stay (LOS) between the pre-intervention and post-intervention cohorts, assuming a standard deviation of 18 h. A total of 339 records were included for data analysis, 170 in the pre-intervention cohort and 169 in the post-intervention cohort. To assess the difference between groups with respect to the primary outcome of LOS, linear regression was used with and without adjusting for covariates. Differences in dichotomous secondary outcomes were assessed using binary logistic regression. Differences in continuous secondary outcomes were assessed via a two-sample t-test or Wilcoxon rank sum test. Individual components of protocol adherence were compared using chi-square tests.

RESULTS

Mean LOS was 80.5 ± 22.9 h and 82.3 ± 28.0 h, pre- and post-intervention respectively. There was no difference in LOS between the 2 cohorts (difference of means = 1.8 h; 95% confidence interval (CI): (-3.7, 7.3); p = .51). Cesarean procedure infection decreased from 11.8% pre-intervention to 5.3% post-intervention, corresponding to a 58% decrease in odds of cesarean procedure infection (odds ratio (OR)=0.42; 95% CI: (0.19, 0.96); p = .04). Inpatient opioid use also significantly decreased in the post-intervention cohort with a median MME per 12 h-period of 5.1 (25^th percentile = 2.2, 75^th percentile = 7.8) pre-intervention and 3.3 (25^th percentile = 1.0, 75^th percentile = 7.6) post-intervention (p = .04).

CONCLUSION

The results of this study support the implementation of an ERAS for CD protocol based on ERAS Society recommendations as evidenced by the statistically significant decrease observed in both procedure-related infection rates and inpatient opioid use. We did not find a significant difference in LOS, which leaves room for further investigation into factors that impact LOS after CD.

Comparison of the analgesic effects of two quadratus lumborum blocks (QLBs), QLB type II vs QLB type III, in caesarean delivery: A randomised study

BACKGROUND

Quadratus lumborum blocks (QLBs) are relatively novel regional anaesthesia techniques, and the efficacy of all three types of QLB for postoperative analgesia in caesarean delivery (CD) has been demonstrated in separate studies. The aim of the present study is to compare the analgesic efficacy of the QLB-II and QLB-III blocks performed at the end of surgery in patients undergoing spinal anaesthesia for CD.

METHODS

We conducted a comparative, blinded, prospective, randomised and efficiency study. A total of 80 patients scheduled for elective CD under spinal anaesthesia were randomly allocated to receive either bilateral ultrasound-guided QLB-II or QLB-III block in a 1:1 ratio. The primary outcome was opioid consumption administered by a patient-controlled analgesia in the first 24 hours postoperatively. The secondary outcome of the study was pain intensity. Also, the time of first opioid requirement and the presence of nausea and vomiting were recorded.

RESULTS

Morphine consumption was statistically significantly lower in the QLB-III group when compared with the QLB-II group at the 3rd, 6th, 12th and 24th hours (P < .001, P < .001, P = .004, and P = .015, respectively). The QLB-III group showed significantly lower pain scores at rest at the 1st, 3rd, 6th, 9th and 24th hours after surgery (P < .001, P < .001, P < .001, P = .007 and P < .001, respectively). The QLB-III group also showed significantly lower pain score on movement at all measurement times (P < .001).

CONCLUSIONS

The analgesic efficacy of QLB-III was superior to QLB-II in patients who had undergone CD under spinal anaesthesia without use of intrathecal opioids and nonsteroidal anti-inflammatory drugs.