Neuraxial clonidine is not associated with lower post-cesarean opioid consumption or pain scores in parturients on chronic buprenorphine therapy: a retrospective cohort study

PURPOSE

Adequate post-cesarean delivery analgesia can be difficult to achieve for women diagnosed with opioid use disorder receiving buprenorphine. We sought to determine if neuraxial clonidine administration is associated with decreased opioid consumption and pain scores following cesarean delivery in women receiving chronic buprenorphine therapy.

METHODS

This was a retrospective cohort study at a tertiary care teaching hospital of women undergoing cesarean delivery with or without neuraxial clonidine administration while receiving chronic buprenorphine. The primary outcome was opioid consumption (in morphine milligram equivalents) 0-6 h following cesarean delivery. Secondary outcomes included opioid consumption 0-24 h post-cesarean, median postoperative pain scores 0-24 h, and rates of intraoperative anesthetic supplementation. Multivariable analysis evaluating the adjusted effects of neuraxial clonidine on outcomes was conducted using linear regression, proportional odds model, and logistic regression separately.

RESULTS

196 women met inclusion criteria, of which 145 (74%) received neuraxial clonidine while 51 (26%) did not. In univariate analysis, there was no significant difference in opioid consumption 0-6 h post-cesarean delivery between the clonidine (8 [IQR 0, 15]) and control (1 [IQR 0, 8]) groups (P = 0.14). After adjusting for potential confounders, there remained no significant association with neuraxial clonidine administration 0-6 h (Difference in means 2.77, 95% CI [- 0.89 to 6.44], P = 0.14) or 0-24 h (Difference in means 8.56, 95% CI [- 16.99 to 34.11], P = 0.51).

CONCLUSION

In parturients receiving chronic buprenorphine therapy at the time of cesarean delivery, neuraxial clonidine administration was not associated with decreased postoperative opioid consumption, median pain scores, or the need for intraoperative supplementation.

Implementation of an Epidural Rounding Reminder in the Electronic Medical Record Improves Performance of Standardized Patient Assessments during Labor

BACKGROUND

Poorly functioning labor epidural catheters lead to pain and dissatisfaction. Regular catheter assessment ensures timely identification of malfunction and may improve safety by facilitating rapid and successful conversion to general anesthesia for emergency cesarean. Informatics-based systems encourage standardization of care to identify epidural malfunctions earlier.

OBJECTIVES

This article demonstrates that visual epidural rounding reminder display on an electronic patient board would alert clinicians to elapsed time and decrease mean time between assessments.

METHODS

As a quality initiative, we implemented an epidural rounding reminder on our obstetric patient board. The reminder indicated the number of elapsed minutes since placement or last patient assessment. We retrospectively reviewed labor epidural charts 3 months prior to and 5 months following reminder implementation, with a 4-week washout period. The primary outcome was mean time between documented epidural assessments, with secondary outcomes including maximum time between assessments, total number of assessments during labor, catheter replacement rates, and patient satisfaction. Unadjusted comparisons between pre- and postimplementation groups were conducted using Wilcoxon's rank-sum and Pearson's chi-square tests, as appropriate. A test for equal variances was conducted for time between assessment outcomes.

RESULTS

Following implementation, mean time between assessments decreased from a median of 173 (interquartile range [IQR]: 53, 314) to 100 (IQR: 74, 125) minutes (p <0.001), and maximum time between assessments decreased from median 330 (IQR: 60, 542) to 162 (IQR: 125, 212) minutes (p < 0.001). Total number of evaluations during labor increased from 3 (IQR: 2, 4) to 5 (IQR: 3, 7; p < 0.001). Decreased variance in mean and maximum time between assessments was noted following reminder implementation (p < 0.001). Epidural replacement rates decreased from 14 to 5% postimplementation (p < 0.001). Patient satisfaction was unchanged.

CONCLUSION

Implementation of an informatics-based solution can promote standardization of care. A simple epidural rounding reminder prompted clinicians to perform more frequent labor epidural assessments. In the future, these process improvements must be linked to improvements in patient experiences and outcomes.

Risk assessment tools to predict postpartum hemorrhage

Postpartum hemorrhage (PPH) is a leading cause of maternal morbidity and mortality, and accurate risk assessments may allow providers to anticipate and prevent serious hemorrhage-related adverse events. Multiple category-based tools have been developed by national societies through expert consensus, and these tools assign low, medium, or high risk of hemorrhage based on a review of each patient's risk factors. Validation studies of these tools show varying performance, with a wide range of positive and negative predictive values. Risk prediction models for PPH have been developed and studied, and these models offer the advantage of more nuanced and individualized prediction. However, there are no published studies demonstrating external validation or successful clinical use of such models. Future work should include refinement of these models, study of best practices for implementation, and ultimately linkage of prediction to improved patient outcomes.

Post-cesarean gabapentin is not associated with lower opioid consumption or pain scores in women on chronic buprenorphine therapy: A 10-year retrospective cohort study

STUDY OBJECTIVE

To determine if postoperative gabapentin administration is associated with decreased opioid consumption or pain scores following cesarean delivery in women on chronic buprenorphine.

DESIGN

Retrospective cohort study.

SETTING

Postoperative recovery area and postpartum inpatient unit.

PATIENTS

214 women undergoing cesarean delivery while on chronic buprenorphine at a single institution between 2007 and 2017.

INTERVENTIONS

Gabapentin treatment for post-cesarean analgesia.

MEASUREMENTS

The primary outcome was opioid consumption in morphine milligram equivalents, comparing patients who received ≥1 dose of gabapentin within 24 h of cesarean delivery to those who did not. Secondary outcomes included opioid consumption 24-48 and 48-72 h post-cesarean and postoperative numerical rating scale pain scores.

MAIN RESULTS

Of 214 included patients, 64 (30%) received gabapentin while 150 (70%) did not. Gabapentin patients were more likely than controls to have received neuraxial fentanyl (30% vs. 14%, p = 0.01) and transversus abdominis plane block (6% vs. 1%, p = 0.05) and overall received higher doses of ketorolac and acetaminophen. Control patients were more likely to have received neuraxial morphine (78% vs. 90%, p = 0.04) and received higher doses of ibuprofen. In unadjusted analysis, there was no significant difference in morphine milligram equivalent consumption 0-24 h postoperatively between gabapentin (55 mg [IQR 26,84]) and control (53 mg [IQR 28,75]) groups (p = 0.38). After controlling for potential confounders, there remained no significant effect of gabapentin administration (overall effect p = 0.99). Opioid consumption and pain scores were also not significantly different at any other time points.

CONCLUSIONS

In parturients receiving chronic buprenorphine, inclusion of gabapentin in a multimodal analgesic regimen was not associated with lower opioid consumption or pain scores during the first 72 h after cesarean delivery. Prospective randomized studies are needed to confirm these findings.

Labor prior to cesarean delivery associated with higher post-discharge opioid consumption

Background

Severe acute post-cesarean delivery (CD) pain has been associated with an increased risk for persistent pain and postpartum depression. Identification of women at increased risk for pain can be used to optimize post-cesarean analgesia. The impact of labor prior to CD (intrapartum CD) on acute post-operative pain and opioid use is unclear. We hypothesized that intrapartum CD, which has been associated with both increased inflammation and affective distress related to an unexpected surgical procedure, would result in higher postoperative pain scores and increased opioid intake.

Methods

This is a secondary analysis of a prospective cohort study examining opioid use up to 2 weeks following CD. Women undergoing CD at six academic medical centers in the United States 9/2014-3/2016 were contacted by phone two weeks following discharge. Participants completed a structured interview that included questions about postoperative pain scores and opioid utilization. They were asked to retrospectively estimate their maximal pain score on an 11-point numeric rating scale at multiple time points, including day of surgery, during hospitalization, immediately after discharge, 1^st week, and 2^nd week following discharge.

Pain scores over time were assessed utilizing a generalized linear mixed-effects model with the patient identifier being a random effect, adjusting for an a priori defined set of confounders. A multivariate negative binomial model was utilized to assess the association between intrapartum CD and opioid utilization after discharge, also adjusting for the same confounders. In the context of non-random prescription distribution, this model was constructed with an offset for the number of tablets dispensed.

Results

A total of 720 women were enrolled, 392 with and 328 without labor prior to CD. Patients with intrapartum CD were younger, less likely to undergo repeat CD or additional surgical procedures, and more likely to experience a complication of CD.

Women with intrapartum CD consumed more opioid tablets following discharge than women without labor (median 20, IQR 10–30 versus 17, IQR 6–30; p = 0.005). This association persisted after adjustment for confounders (incidence rate ratio 1.16, 95% CI 1.05–1.29; p = 0.004). Pain scores on the day of surgery were higher in women with intrapartum CD (difference 0.91, 95% CI 0.52–1.30; adj. p = <0.001) even after adjustment for confounders. Pain scores at other time points were not meaningfully different between the two groups.

Conclusion

Intrapartum CD is associated with worse pain on the day of surgery but not other time points. Opioid requirements following discharge were modestly increased following intrapartum CD.

Improving ACGME Compliance for Obstetric Anesthesiology Fellows Using an Automated Email Notification System

BACKGROUND

The Accreditation Council for Graduate Medical Education establishes minimum case requirements for trainees. In the subspecialty of obstetric anesthesiology, requirements for fellow participation in nonobstetric antenatal procedures pose a particular challenge due to the physical location remote from labor and delivery and frequent last-minute scheduling.

OBJECTIVES

In response to this challenge, we implemented an informatics-based notification system, with the aim of increasing fellow participation in nonobstetric antenatal surgeries.

METHODS

In December 2014 an automated email notification system to inform obstetric anesthesiology fellows of scheduled nonobstetric surgeries in pregnant patients was initiated. Cases were identified via daily automated query of the preoperative evaluation database looking for structured documentation of current pregnancy. Information on flagged cases including patient medical record number, operating room location, and date and time of procedure were communicated to fellows via automated email daily. Median fellow participation in nonobstetric antenatal procedures per quarter before and after implementation were compared using an exact Wilcoxon-Mann-Whitney test due to low baseline absolute counts. The fraction of antenatal cases representing nonobstetric procedures completed by fellows before and after implementation was compared using a Fisher's exact test.

RESULTS

The number of nonobstetric antenatal cases logged by fellows per quarter increased significantly following implementation, from median 0[0,1] to 3[1,6] cases/quarter (p = 0.007). Additionally, nonobstetric antenatal cases completed by fellows as a percentage of total antenatal cases completed increased from 14% in preimplementation years to 52% in postimplementation years (p < 0.001).

CONCLUSION

Through an automated email system to identify nonobstetric antenatal procedures in pregnant patients, we were able to increase the number of these cases completed by fellows during 3 years following implementation.

Quantifying the incidence of clinically significant respiratory depression in women with and without obesity class III receiving neuraxial morphine for post-cesarean analgesia: a retrospective cohort study

BACKGROUND

Obesity is a suspected risk factor for respiratory depression following neuraxial morphine for post-cesarean analgesia, however monitoring guidelines for obese obstetric patients are based on small, limited studies. We tested the hypothesis that clinically significant respiratory depression following neuraxial morphine occurs more commonly in women with body mass index (BMI) ≥40 kg/m² compared with BMI <40 kg/m².

METHODS

We conducted a single-center, retrospective chart review (2006-2017) of obstetric patients with clinically significant respiratory depression following neuraxial morphine, defined as: (1) opioid antagonist administration; (2) rapid response team activation (initiated in April 2010); or (3) tracheal intubation due to a respiratory event. The incidence of respiratory depression was compared between women with BMI ≥40 kg/m² and BMI <40 kg/m².

RESULTS

In total, 11 327 women received neuraxial morphine (n=1945 BMI ≥40 kg/m²; n=9382 BMI <40 kg/m²). Women with BMI ≥40 kg/m² had higher rates of sleep apnea, hypertensive disorders, and magnesium administration. Sixteen cases of clinically significant respiratory depression occurred within seven days postpartum. The incidence did not significantly differ between groups (odds ratio 2.2, 95% CI 0.6 to 6.9, P=0.174). Neuraxial morphine was not deemed causative in any case, however women with BMI ≥40 kg/m² had higher rates of tracheal intubation unrelated to neuraxial morphine (2/1945 vs. 0/9382, P=0.029).

CONCLUSIONS

Respiratory depression in this population is rare. A larger sample (∼75 000) is required to determine whether the incidence is higher with BMI ≥40 kg/m². Tracheal intubation was higher among the BMI ≥40 kg/m² cohort, likely due to more comorbidities.

A cluster quasi-randomized controlled trial of an interactive, monthly obstetric anesthesiology curriculum: impact on resident satisfaction and knowledge retention

BACKGROUND

Increasingly, evidence supports the use of educational paradigms that focus on teacher-learner interaction and learner engagement. We redesigned our monthly obstetric anesthesia resident didactics from a lecture-based curriculum to an interactive format including problem-based learning, case discussion, question/answer sessions, and simulation. We hypothesized that the new curriculum would improve resident satisfaction with the educational experience, satisfaction with the rotation, and knowledge retention.

METHODS

Fifty-three anesthesiology residents were prospectively recruited and quasi-randomized through an alternating-month pattern to attend either interactive sessions or traditional lectures. Residents completed a daily satisfaction survey about quality of teaching sessions and a comprehensive satisfaction survey at the conclusion of the rotation. Knowledge retention was assessed with a knowledge test completed on the final day. The primary outcome was daily satisfaction with the curriculum, and secondary outcomes included overall satisfaction with the curriculum, overall rotation satisfaction, and within-resident difference between pre- and post-knowledge test scores.

RESULTS

No differences were observed in daily resident satisfaction after interactive sessions vs traditional lectures. Furthermore, no differences were observed between the interactive sessions and traditional lecture groups in overall satisfaction with the curriculum, overall satisfaction with the entire rotation or within-resident difference between pre- and post-knowledge test scores.

CONCLUSIONS

Our study failed to demonstrate improvement in resident satisfaction or knowledge retention following implementation of an interactive curriculum on a month-long obstetric anesthesia rotation. Reasons may include misalignment of the intervention with measured study outcomes, lack of sensitivity of the survey tools, and inadequate training of faculty presenters.

Association of Interindividual Variation in Plasma Oxytocin With Postcesarean Incisional Pain

Oxytocin has known antinociceptive effects and is upregulated perinatally. This pilot study investigated the association of plasma oxytocin and postcesarean incisional pain. Plasma samples from 18 patients undergoing elective cesarean delivery were drawn at 1 hour preoperatively and 1 and 24 hours postoperatively and analyzed by using enzyme-linked immunosorbent assay. Pain was assessed at 1 day, 8 weeks, 3 months, and 6 months postoperatively. Incisional pain at 24 hours was inversely correlated with 1- and 24-hour oxytocin levels, with higher plasma oxytocin associated with lower pain (ρ, -0.52 and -0.66; P < .05).