State-Level Indicators of Structural Racism and Severe Adverse Maternal Outcomes During Childbirth.

OBJECTIVES: Structural racism (SR) is viewed as a root cause of racial and ethnic disparities in maternal health outcomes. However, evidence linking SR to increased odds of severe adverse maternal outcomes (SAMO) is scant. This study assessed the association between state-level indicators of SR and SAMO during childbirth. METHODS: Data for non-Hispanic Black and non-Hispanic white women came from the US Natality file, 2017-2018. The exposures were state-level Black-to-white inequity ratios for lower education level, unemployment, and prison incarceration. The outcome was patient-level SAMO, including eclampsia, blood transfusion, hysterectomy, or intensive care unit admission. Adjusted odds ratios (aORs) of SAMO associated with each ratio were estimated using multilevel models adjusting for patient, hospital, and state characteristics. RESULTS: A total of 4,804,488 birth certificates were analyzed, with 22.5% for Black women. SAMO incidence was 106.4 per 10,000 (95% CI 104.5, 108.4) for Black women, and 72.7 per 10,000 (95% CI 71.8, 73.6) for white women. Odds of SAMO increased 35% per 1-unit increase in the unemployment ratio for Black women (aOR 1.35; 95% CI 1.04, 1.73), and 16% for white women (aOR 1.16; 95% CI 1.01, 1.33). Odds of SAMO increased 6% per 1-unit increase in the incarceration ratio for Black women (aOR 1.06; 95% CI 1.03, 1.10), and 4% for white women (aOR 1.04; 95% CI 1.02, 1.06). No significant association was observed between SAMO and the lower education level ratio. CONCLUSIONS FOR PRACTICE: State-level Black-to-white inequity ratios for unemployment and incarceration are associated with significantly increased odds of SAMO.

Medicaid expansion and risk of eclampsia.

BACKGROUND: Eclampsia is an indicator of severe maternal morbidity and can be prevented through increased prenatal care access and early prenatal care utilization. The 2014 Medicaid expansion under the Patient Protection and Affordable Care Act allowed states to expand Medicaid coverage to nonelderly adults with incomes up to 138% of the federal poverty level. Its implementation has led to a significant increase in prenatal care access and utilization. OBJECTIVE: This study aimed to assess the association of Medicaid expansion under the Affordable Care Act with eclampsia incidence. STUDY DESIGN: This natural experiment study was based on US birth certificate data from January 2010 to December 2018 in 16 states that expanded Medicaid in January 2014 and in 13 states that did not expand Medicaid during the study period. The outcome was eclampsia incidence, the intervention was the implementation of the Medicaid expansion, and the exposure was state expansion status. Using the interrupted time series method, we compared temporal trends in the incidence of eclampsia before and after the intervention in expansion vs non-expansion states with adjustments for patient and hospital county characteristics. RESULTS: Of the 21,570,021 birth certificates analyzed, 11,433,862 (53.0%) were in expansion states and 12,035,159 (55.8%) were in the postintervention period. The diagnosis of eclampsia was recorded in 42,677 birth certificates or 19.8 per 10,000 (95% confidence interval, 19.6-20.0). The incidence of eclampsia was higher for Black people (29.1 per 10,000) than for White (20.7 per 10,000), Hispanic (15.3 per 10,000), and birthing people of other race and ethnicity (15.4 per 10,000). In the expansion states, the incidence of eclampsia increased during the preintervention period and decreased during the postintervention period; in the nonexpansion states, a reverse pattern was observed. A statistically significant difference was observed between expansion and nonexpansion states in temporal trends between the pre- and postintervention periods, with an overall 1.6% decrease (95% confidence interval, 1.3-1.9) in the incidence of eclampsia in expansion states compared with nonexpansion states. The results were consistent in subgroup analyses according to maternal race and ethnicity, education level (less than high school or high school and higher), parity (nulliparous or parous), delivery mode (vaginal or cesarean delivery), and poverty in the residence county (high or low). CONCLUSION: Implementation of the Affordable Care Act Medicaid expansion was associated with a small statistically significant reduction in the incidence of eclampsia. Its clinical significance and cost-effectiveness remain to be determined.

Association of the United States Affordable Care Act Dependent Coverage Provision with Labor Neuraxial Analgesia Use.

BACKGROUND: Providing continuous health insurance coverage during the perinatal period may increase access to and utilization of labor neuraxial analgesia. This study tested the hypothesis that implementation of the 2010 Dependent Coverage Provision of the Patient Protection and Affordable Care Act, requiring private health insurers to allow young adults to remain on their parent's plan until age 26 yr, was associated with increased labor neuraxial analgesia use. METHODS: This study used a natural experiment design and birth certificate data for spontaneous vaginal deliveries in 28 U.S. states between 2009 and 2013. The intervention was the Dependent Coverage Provision, categorized into pre- and postintervention periods (January 2009 to August 2010 and September 2010 to December 2013, respectively). The exposure was women's age, categorized as exposed (21 to 25 yr) and unexposed (27 to 31 yr). The outcome was the labor neuraxial analgesia utilization rate. RESULTS: Of the 4,515,667 birth certificates analyzed, 3,033,129 (67.2%) indicated labor neuraxial analgesia use. For women aged 21 to 25 yr, labor neuraxial analgesia utilization rates were 64.9% during the preintervention period and 68.9% during the postintervention period (difference, 4.0%; 95% CI, 3.9 to 4.2). For women aged 27 to 31 yr, labor neuraxial analgesia utilization rates were 64.9% during the preintervention period and 67.7% during the postintervention period (difference, 2.8%; 95% CI, 2.7 to 2.9). After adjustment, implementation of the Dependent Coverage Provision was associated with a 1.0% (95% CI, 0.8 to 1.2) absolute increase in labor neuraxial analgesia utilization rate among women aged 21 to 25 yr compared with women aged 27 to 31 yr. The increase was statistically significant for White and Hispanic women but not for Black and Other race and ethnicity women. CONCLUSIONS: Implementation of the Dependent Coverage Provision was associated with a statistically significant increase in labor neuraxial analgesia use, but the small effect size is unlikely of clinical significance.

Health equity research in obstetric anesthesia.

PURPOSE OF REVIEW: Health equity is an important priority for obstetric anesthesia, but describing disparities in perinatal care process and health outcome is insufficient to achieve this goal. Conceptualizing and framing disparity is a prerequisite to pose meaningful research questions. We emphasize the need to hypothesize and test which mechanisms and drivers are instrumental for disparities in perinatal processes and outcomes, in order to target, test and refine effective countermeasures. RECENT FINDINGS: With an emphasis on methodology and measurement, we sketch how health systems and disparity research may advance maternal health equity by narrating, conceptualizing, and investigating social determinants of health as key drivers of perinatal disparity, by identifying the granular mechanism of this disparity, by making the economic case to address them, and by testing specific interventions to advance obstetric health equity. SUMMARY: Measuring social determinants of health and meaningful perinatal processes and outcomes precisely and accurately at the individual, family, community/neighborhood level is a prerequisite for healthcare disparity research. A focus on elucidating the precise mechanism driving disparity in processes of obstetric care would inform a more rational effort to promote health equity. Implementation scientists should rigorously investigate in prospective trials, which countermeasures are most efficient and effective in mitigating perinatal outcome disparities.

Association of Medicaid Expansion Under the Affordable Care Act With Perinatal Care Access and Utilization Among Low-Income Women: A Systematic Review and Meta-analysis.

OBJECTIVE: To synthesize the empirical research evidence about the association between Medicaid expansion under the Affordable Care Act (ACA) and increasing perinatal care access and utilization among low-income women. DATA SOURCES: We searched MEDLINE through PubMed (1966-present), EMBASE (Ovid), the Cumulative Index to Nursing and Allied Health (1982-present), PAIS Index (ProQuest), Web of Science (1900-present), and the Cochrane Central Register of Controlled Trials. Our review focuses on the association between Medicaid expansion under the ACA and perinatal care access and utilization, which cannot be subjected to randomized controlled trials, therefore ClinicalTrials.gov was not included in our search. METHODS OF STUDY SELECTION: A comprehensive search of the research literature was performed using Covidence. Studies were eligible if they were based on population data and research designs ensuring that the exposure (ie, Medicaid expansion under the ACA) preceded the perinatal care access or utilization outcome, had an appropriate comparison group, presented quantitative data, and examined pregnant or postpartum women. The search in six bibliographic databases returned 1,243 records, with 855 abstracts reviewed, 34 full-text articles screened for eligibility, and nine eligible studies included in the systematic review. TABULATION, INTEGRATION, AND RESULTS: Stata 16 software was used to generate summary estimates, forest plots, funnel plots, and heterogeneity statistics. Random effects modeling based on pooled data revealed that Medicaid expansion was associated with a 6.1% increase in Medicaid enrollment for pregnant women (95% CI 1.3-10.9%) and a 3.3% increase in perinatal care utilization (95% CI 0.2-6.3%). CONCLUSION: Medicaid expansion under the ACA is associated with a modest and statistically significant increase in perinatal care access and utilization among low-income women.

The 2014 New York State Medicaid Expansion and Severe Maternal Morbidity During Delivery Hospitalizations.

BACKGROUND: Medicaid expansions under the Affordable Care Act have increased insurance coverage and prenatal care utilization in low-income women. However, it is not clear whether they are associated with any measurable improvement in maternal health outcomes. In this study, we compared the changes in the incidence of severe maternal morbidity (SMM) during delivery hospitalizations between low- and high-income women associated with the 2014 Medicaid expansion in New York State. METHODS: Data for this retrospective cohort study came from the 2006-2016 New York State Inpatient Database, a census of discharge records from community hospitals. The outcome was SMM during delivery hospitalizations, as defined by the Centers for Disease Control and Prevention. We used regression coefficients (ß) from multivariable logistic models: (1) to compare independently in low-income women and in high-income women the changes in slopes in the incidence of SMM before (2006-2013) and after (2014-2016) the expansion, and (2) to compare low- and high-income women for the changes in slopes in the incidence of SMM before and after the expansion. RESULTS: A total of 2,286,975 delivery hospitalizations were analyzed. The proportion of Medicaid beneficiaries in parturients increased a relative 12.1% (95% confidence interval [CI], 11.8-12.4), from 42.9% in the preexpansion period to 48.1% in the postexpansion period, whereas the proportion of the uninsured decreased a relative 4.8% (95% CI, 2.8-6.8). Multivariable logistic modeling revealed that implementation of the 2014 Medicaid expansion was associated with a decreased slope during the postexpansion period both in low-income women (ß = -0.0161 or 1.6% decrease; 95% CI, -0.0190 to -0.0132) and in high-income women (ß = -0.0111 or 1.1% decrease; 95% CI, -0.0130 to -0.0091). The decrease in slope during the postexpansion period was greater in low- than in high-income women (ß = -0.0042 or 0.42% difference; 95% CI, -0.0076 to -0.0007). CONCLUSIONS: Implementation of the Medicaid expansion in 2014 in New York State is associated with a small but statistically significant reduction in the incidence of SMM in low-income women compared with high-income women.

Risk for and disparities in critical care during delivery hospitalizations.

BACKGROUND: Need for critical care during delivery hospitalizations may be an important maternal outcome measure, but it is not well characterized. OBJECTIVE: This study aimed to characterize the risks and disparities in critical care diagnoses and interventions during delivery hospitalizations. STUDY DESIGN: This serial cross-sectional study used the 2000-2014 National Inpatient Sample. Here, the primary outcome was a composite of critical care interventions and diagnoses, including mechanical ventilation and intubation, central monitoring, septicemia, coma, acute cerebrovascular disease, extracorporeal membrane oxygenation, Swan-Ganz catheter monitoring, cardiac rhythm conversion, and respiratory failure. Temporal trends, risk of death, and the proportion of deaths with a critical care composite diagnosis were determined. Unadjusted and adjusted log-linear regression models were fit with a critical care composite as the outcome, adjusting for demographic, clinical, and hospital factors. To evaluate the role of critical care interventions in disparities, analyses were stratified by maternal race and ethnicity. RESULTS: Of 45.8 million deliveries identified, 0.21% had a critical care procedure or diagnosis during the delivery hospitalization. Overall, 75.8% of maternal deaths had an associated diagnosis from a critical care composite. The critical composite increased from 17.9 to 30.3 per 10,000 deliveries from 2000 to 2014 with an average annual percentage change of 3.4% (95% confidence interval, 1.3-5.5). Mechanical ventilation and intubation (21.5% of cases) and respiratory failure (54.8% of cases) were the most common diagnoses present in the composite. Although non-Hispanic black women were at 32.4% higher risk than non-Hispanic white women to die in the setting of a critical care diagnosis (2.2% vs 1.7%; P<.01), they were 162% more likely to have a critical care diagnosis (risk ratio, 2.62; 95% confidence interval, 2.58-2.66). Of clinical factors, primary cesarean delivery (adjusted relative risk, 7.54; 95% confidence interval, 7.43-7.65), postpartum hemorrhage (adjusted relative risk, 5.11; 95% confidence interval, 5.02-5.19), and chronic kidney disease (adjusted relative risk, 4.06; 95% confidence interval, 3.89-4.23) were associated with the highest adjusted risk of a critical care composite. CONCLUSION: Three-quarters of maternal deaths were associated with a critical care diagnosis or procedure. The rate of critical care during delivery hospitalizations increased over the study period. Maternal mortality disparities may result from risks of conditions that require critical care rather than the care received once a critical care condition has developed.

Emergency-to-Elective Surgery Ratio: A Global Indicator of Access to Surgical Care.

BACKGROUND: Surgical care is essential to health systems but remains a challenge for low- and middle-income countries (LMICs). Current metrics to assess access and delivery of surgical care focus on the structural components of surgery and are not readily applicable to all settings. This study assesses a new metric for surgical care access and delivery, the ratio of emergent surgery to elective surgery (Ee ratio), which represents the number of emergency surgeries performed for every 100 elective surgeries. METHODS: A systematic search of PubMed and Medline was conducted for studies describing surgical volume and acuity published between 2006 and 2016. The relationship between Ee ratio and three national indicators (gross domestic product, per capital healthcare spending, and physician density) was analyzed using weighted Pearson correlation coefficients (r w) and linear regression models. RESULTS: A total of 29 studies with 33 datasets were included for analyses. The median Ee ratio was 14.6 (IQR 5.5-62.6), with a range from 1.6 to 557.4. For countries in sub-Saharan Africa the median value was 62.6 (IQR 17.8-111.0), compared to 9.4 (IQR 3.4-13.4) for the United States and 5.5 (IQR 4.4-10.1) for European countries. In multivariable linear regression, the per capita healthcare spending was inversely associated with the Ee ratio, with a 63-point decrease in the Ee ratio for each 1 point increase in the log of the per capita healthcare spending (regression coefficient ß = -63.2; 95% CI -119.6 to -6.9; P = 0.036). CONCLUSIONS: The Ee ratio appears to be a simple and valid indicator of access to available surgical care. Global health efforts may focus on investment in low-resource settings to improve access to available surgical care.

Socioeconomic Deprivation and Utilization of Anesthetic Care During Pregnancy and Delivery: A Secondary Analysis of a French Prospective, Multicenter, Cohort Study.

BACKGROUND: Socioeconomic deprivation is associated with reduced use of antenatal resources and poor maternal outcomes with pregnancy. Research examining the association between socioeconomic deprivation and use of obstetric anesthesia care in a country providing universal health coverage is scarce. We hypothesized that in a country providing universal health coverage, France, socioeconomic deprivation is not associated with reduced use of anesthetic care during pregnancy and delivery. This study aimed to examine the association between socioeconomic deprivation and (1) completion of a mandatory preanesthetic evaluation during pregnancy and (2) use of neuraxial analgesia during labor. METHODS: Data were from a cohort of 10,419 women who delivered between 2010 and 2011 in 4 public teaching hospitals in Paris. We used a deprivation index that included 4 criteria: social isolation, poor housing condition, no work-related household income, and state-funded health care insurance. Socioeconomic deprivation was defined as a deprivation index greater than 1. Preanesthetic evaluation was considered completed if performed more than 48 hours before delivery. The association between socioeconomic deprivation and completion of the preanesthetic evaluation and use of neuraxial labor analgesia was assessed by multivariable logistic regression adjusting for education level, country of birth, and maternal and pregnancy characteristics. RESULTS: Preanesthetic evaluation was completed for 8142 of the 8624 women (94.4%) analyzed and neuraxial labor analgesia was used by 6258 of the 6834 women analyzed (91.6%). After adjustment, socioeconomic deprivation was associated with reduced probability of completed preanesthetic evaluation (adjusted odds ratio 0.88 [95% confidence interval, 0.79-0.98]; P = .027) but not use of neuraxial labor analgesia (adjusted odds ratio 0.97 [95% confidence interval, 0.87-1.07]; P = .540). CONCLUSIONS: In a country providing universal health care coverage, women who were socioeconomically deprived showed reduced completion of preanesthetic evaluation during pregnancy but not reduced use of neuraxial labor analgesia. Interventions should be targeted to socioeconomically deprived women to increase the completion of the preanesthetic evaluation.

Hospital-Level Factors Associated with Anesthesia-Related Adverse Events in Cesarean Deliveries, New York State, 2009-2011.

BACKGROUND: Marked variation across hospitals in adverse maternal outcomes in cesarean deliveries is reported, including anesthesia-related adverse events (ARAEs). Identification of hospital-level characteristics accounting for this variation may help guide interventions to improve anesthesia care quality. In this study, we examined the association between hospital-level characteristics and ARAEs in cesarean deliveries and assessed individual hospital performance. METHODS: Discharge records for cesarean deliveries, ARAEs, and patient characteristics in the State Inpatient Database for New York State 2009 to 2011 were identified with International Classification of Diseases, Ninth Revision, Clinical Modification codes. The hospital reporting index was calculated as the sum of International Classification of Diseases, Ninth Revision, Clinical Modification codes divided by the number of discharges. Data on hospital characteristics were obtained from the American Hospital Association and the Area Health Resources files. Multilevel modeling was used to examine the association of hospital-level characteristics with ARAEs and to assess individual hospital performance. RESULTS: The study included 236,960 discharges indicating cesarean deliveries in 141 hospitals; 1557 discharges recorded at least 1 ARAE (6.6 per 1000; 95% confidence interval [CI], 6.2-6.9). The following factors were associated with a significantly increased risk of ARAEs: Charlson comorbidity index ≥ 1 (adjusted odds ratio [aOR], 1.2), multiple gestation (aOR, 1.3), postpartum hemorrhage (aOR, 1.5), general anesthesia (aOR, 1.3), hospital annual cesarean delivery volume <200 (aOR, 2.3), and reporting index (aOR, 1.1 per 1 increase per discharge). Fifteen percent of the between-hospital variation in ARAEs was explained by the hospital annual cesarean delivery volume and 6% by the reporting index. Eight hospitals (6%) were classified as good-performing, 104 (74%) as average-performing, and 29 (21%) as bad-performing hospitals. Compared with good-performing hospitals, a 2.3-fold (95% CI, 1.7-3.0) and 5.9-fold (95% CI, 4.5-7.8) increase in the rate of ARAEs was observed in average- and bad-performing hospitals, respectively. Bringing up bad-performing hospitals to the level of average-performing hospitals would prevent 466 ARAEs (30%). CONCLUSIONS: Low cesarean delivery volume is the strongest hospital-level predictor of ARAEs in cesarean deliveries and the main determinant of between-hospital variation. Future study to identify other factors and interventions to improve performance in bad-performing hospitals is warranted.

Costs Associated with Anesthesia-Related Adverse Events During Labor and Delivery in New York State, 2010.

BACKGROUND: The safety of anesthetic care provided during childbirth has improved during the past 2 decades in the United States, with a marked decrease in the rate of anesthesia-related adverse events (ARAEs). To date, there is little research on the costs of ARAEs in obstetrics. This study aims to assess the excess cost and cost per admission associated with ARAEs during labor and delivery. METHODS: Data came from the New York State Inpatient Database 2010. Discharge records indicating labor and delivery and ARAEs were identified with International Classification of Diseases, Ninth Revision, Clinical Modification codes. ARAEs were defined as minor if not associated with maternal death, cardiac arrest, or severe morbidity. Costs were calculated as the product of hospital charges and the group average all-payer inpatient charge-to-cost conversion ratio. Excess cost was calculated as the difference between the mean cost of discharges with and without ARAEs. The cost per admission was calculated as the product of the excess cost and ARAE incidence. Excess costs and cost per admission were also calculated for 2 pregnancy-related complications: postpartum hemorrhage and preeclampsia/eclampsia. RESULTS: There were 228,104 delivery-related discharges in the study; of these, 1053 recorded at least 1 ARAE (4.6 per 1000), with 1034 (98.2%) of the ARAEs being minor. The adjusted excess cost associated with ARAEs was $1189 (95% confidence interval [CI], 1033-1350) and the cost per admission $5.49 (95% CI, 4.77-6.23). The incidence of postpartum hemorrhage and preeclamspia/eclampsia was 25.1 and 43.8 per 1000, respectively. The adjusted excess cost was $679 (95% CI, 608-748) and $1328 (95% CI, 1272-1378), respectively; the cost per admission was $17.07 (95% CI, 15.27-18.81) and $58.16 (95% CI, 55.72-60.34), respectively. CONCLUSIONS: ARAEs during labor and delivery are associated with significant excess cost. However, the excess cost per admission for ARAEs is significantly less compared with the excess cost per admission for preeclampsia/eclampsia and postpartum hemorrhage.

Pain assessment in the postanaesthesia care unit using pupillometry: A cross-sectional study after standard anaesthetic care.

BACKGROUND: Patients assess their own pain with a numerical rating scale (NRS). In the postanaesthesia care unit (PACU), NRS helps to determine and monitor analgesic administration, but is useless in patients who are unable to communicate. In non-PACU patients, acute pain increases pupillary diameter and pupillary light reflex amplitude (PLRA), the difference between pupillary diameter before and after light stimulation. OBJECTIVES: To study the association between postoperative pain (NRS) and pupillary diameter or PLRA in PACU patients after routine anaesthetic care. DESIGN: Cross-sectional cohort study. SETTING: Bichat-Claude Bernard Hospital, Paris. PATIENTS: One hundred and forty-five patients undergoing planned surgery under general anaesthesia. INTERVENTIONS: NRS, pupillary diameter and PLRA were measured on arrival in the PACU. When NRS was more than 4, intravenous morphine titration was started and a second measurement performed. MAIN OUTCOME MEASURES: Association between NRS and pupillary diameter or PLRA was assessed with Pearson correlation coefficient (r) as was association between changes in these variables after morphine titration. RESULTS: Mean NRS was 4.7, and was more than 4 in 79 patients (55%). No statistically significant association was observed between NRS and pupillary diameter (r = 0.10, P = 0.54) or PLRA (r = 0.03, P = 0.72). Twenty-seven patients (19%) received morphine titration with significant decreases in NRS, pupillary diameter and PLRA afterwards. No association was observed between NRS changes and pupillary diameter or PLRA changes. CONCLUSION: Acute postoperative pain is not associated with pupillary diameter or PLRA. Further research is required to develop tools to assess pain in the PACU.

Assessment of pain during labor with pupillometry: a prospective observational study.

BACKGROUND: Pain intensity is usually self-rated by patients with a numeric rating scale (NRS) but this scale cannot be used for noncommunicating patients. In anesthetized patients, experimental noxious stimulus increases pupillary diameter (PD) and pupillary light reflex amplitude (PLRA), the difference between PD before and after light stimulation. Labor pain is an intense acute nonexperimental stimulus, effectively relieved by epidural analgesia. In this prospective observational study, we therefore describe the effects of labor pain and pain relief with epidural analgesia on PD and PLRA, determine their association with pain intensity and determine the ability of a single measurement of PD or PLRA to assess pain. METHODS: In the first stage, pain (11-point NRS), PD, and PLRA were measured in 4 conditions in 26 laboring women: before and after epidural analgesia and in the presence and absence of a uterine contraction. Pupillometry values among the 4 conditions were compared, and the strength of the association between absolute values of pain and PD or PLRA and between pain and changes in PD or PLRA brought about by uterine contraction was assessed with r(2). In the second stage, 1 measurement was performed in 104 laboring women. The strength of the association between pain and PD or PLRA was assessed with r(2). The ability of PD or PLRA to discriminate pain (NRS > 4) was also assessed. RESULTS: In the first stage, a statistically significant increase in pain, PD, and PLRA was observed during a contraction, and this change was abolished after epidural analgesia. The r(2) for the association between pain and changes in PD (r(2) = 0.25 [95% confidence interval, 0.07-0.46] or PLRA (r(2) = 0.34 [0.14-0.56]) brought about by a uterine contraction was higher than the r(2) for the association between pain and absolute values of PD (r(2) = 0.14 [0.04-0.28]) or PLRA (r(2) = 0.22 [0.10-0.37]) suggesting a stronger association for changes than for absolute values. In the second stage, r(2) was 0.23 [0.10-0.38] for PD and 0.26 [0.11-0.40] for PLRA and the area under the receiver operating characteristics curve was 0.82 [0.73-0.91] and 0.80 [0.71-0.89], respectively. CONCLUSIONS: Changes in PD and PLRA brought about by a uterine contraction may be used as a tool to assess analgesia in noncommunicating patients.