Haemodynamic changes during labour: continuous minimally invasive monitoring in 20 healthy parturients

Pregnancy related complications in women with hypertrophic cardiomyopathy: a nationwide population-based cohort study

BACKGROUND

The impact of hypertrophic cardiomyopathy (HCM) on cardiovascular and obstetrical outcomes in pregnant women remains unclear, particularly in Asian populations. This study aimed to evaluate the maternal cardiovascular and obstetrical outcomes in Korean women with HCM.

METHODS

Using data from the Korean National Health Insurance Service database, we identified women who gave birth via cesarean section or vaginal delivery after being diagnosed with HCM between 2006 and 2019. Maternal cardiovascular and obstetrical outcomes were assessed based on the trimester of pregnancy.

RESULTS

This study included 122 women and 158 pregnancies. No maternal deaths were noted; however, 21 cardiovascular events, such as hospital admission for cardiac problems, including heart failure and atrial fibrillation (AF), new-onset AF or ventricular tachycardia (VT) occurred in 14 pregnancies (8.8%). Cardiac events occurred throughout pregnancy with a higher occurrence in the third trimester. Cesarean sections were performed in 49.3% of the cases, and all cardiovascular outcomes occurring after delivery were observed in patients who had undergone cesarean sections. Seven cases involved preterm delivery, and two of these cases were accompanied by cardiac events, specifically AF. Pre-existing arrhythmia (AF: odds ratio (OR): 7.44, 95% confidence interval (CI): 2.61-21.21, P < 0.001; VT: OR: 31.61, 95% CI: 5.85-172.77, P < 0.001) was identified as a predictor for composite outcomes of cardiovascular events or preterm delivery.

CONCLUSIONS

Most pregnant women with HCM were well-tolerated. However, cardiovascular complications could occur in some patients. Therefore, planned delivery may be necessary for selected patients, especially the women with pre-existing arrhythmias.

Recommendations for the Management of High-Risk Cardiac Delivery: ACC Cardiovascular Disease in Women Committee Panel

Maternal mortality is a major public health crisis in the United States. Cardiovascular disease (CVD) is a leading cause of maternal mortality and morbidity. Labor and delivery is a vulnerable time for pregnant individuals with CVD but there is significant heterogeneity in the management of labor and delivery in high-risk patients due in part to paucity of high-quality randomized data. The authors have convened a multidisciplinary panel of cardio-obstetrics experts including cardiologists, obstetricians and maternal fetal medicine physicians, critical care physicians, and anesthesiologists to provide a practical approach to the management of labor and delivery in high-risk individuals with CVD. This expert panel will review key elements of management from mode, timing, and location of delivery to use of invasive monitoring, cardiac devices, and mechanical circulatory support.

Changes in rate-pressure product associated with pregnancy

BACKGROUND

In nonpregnant individuals, the rate-pressure product, the product of heart rate and systolic blood pressure, is used as a noninvasive surrogate of myocardial O2 consumption during cardiac stress testing. Pregnancy is considered a physiological cardiovascular stress test. Evidence describing the impact of pregnancy on myocardial O2 demand, as assessed by the rate-pressure product, is limited.

OBJECTIVE

This study aimed to describe changes in the rate-pressure product for each pregnancy trimester, during labor and delivery, and the postpartum period among low-risk pregnancies.

STUDY DESIGN

This was a retrospective cohort study that assessed uncomplicated pregnancies delivered vaginally at term. We collected rate-pressure product (heart rate × systolic blood pressure) values preconception, during pregnancy for each trimester (at ≤13 weeks + 6/7 days, at 14 weeks + 0/7 days through 27 weeks + 6/7 days, and at ≥28 weeks + 0/7 days), during the labor and delivery encounter (hospital admission until complete cervical dilation, complete cervical dilation until placental delivery, and after placental delivery until hospital discharge), and during the outpatient postpartum visit at 2 to 6 weeks after delivery. We calculated the percentage change at each time point from the preconception rate-pressure product (delta rate-pressure product). We used a mixed-linear model to analyze differences in the mean delta rate-pressure product over time and the influence of prepregnancy age, prepregnancy body mass index, and neuraxial anesthesia status during labor and delivery on these estimates.

RESULTS

Our cohort comprised 316 patients. The mean rate-pressure product increased significantly from preconception starting at the third trimester of pregnancy and during labor and delivery (P≤.05). The mean delta rate-pressure product peaked at 12% and 38% in the third trimester and during labor and delivery, respectively. Prepregnancy body mass index was inversely correlated with the mean delta rate-pressure product changes (estimate, -0.308; 95% confidence interval, -0.536 to -0.80; P=.008). In contrast, neither the prepregnancy age, nor neuraxial anesthesia status during labor had a significant influence on this parameter.

CONCLUSION

This study validates the transient but significant increase in the rate-pressure product, a clinical estimate of myocardial O2 demand, during uncomplicated pregnancies delivered vaginally at term. Pregnant individuals with lower prepregnancy body mass index experienced a sharper increase in this parameter. Patients who receive neuraxial anesthesia during labor and delivery experience similar changes in the rate-pressure product as those who did not.

Predicting fluid responsiveness in spontaneously breathing parturients undergoing caesarean section via carotid artery blood flow and velocity time integral measured by carotid ultrasound: a prospective cohort study

BACKGROUND

Present evidence suggests that the Doppler ultrasonographic indices, such as carotid artery blood flow (CABF) and velocity time integral (VTI), had the ability to predict fluid responsiveness in non-obstetric patients. The purpose of this study was to assess their capacity to predict fluid responsiveness in spontaneous breathing parturients undergoing caesarean section and to determine the effect of detecting and management of hypovolemia (fluid responsiveness) on the incidence of hypotension after anaesthesia.

METHODS

A total of 72 full term singleton parturients undergoing elective caesarean section were enrolled in this study. CABF, VTI, and hemodynamic parameters were recorded before and after fluid challenge and assessed by carotid artery ultrasonography. Fluid responsiveness was defined as an increase in stroke volume index (SVI) of 15% or more after the fluid challenge.

RESULTS

Thirty-one (43%) patients were fluid responders. The area under the ROC curve to predict fluid responsiveness for CABF and VTI were 0.803 (95% CI, 0.701-0.905) and 0.821 (95% CI, 0.720-0.922). The optimal cut-off values of CABF and VTI for fluid responsiveness was 175.9 ml/min (sensitivity of 74.0%; specificity of 78.0%) and 8.7 cm/s (sensitivity of 67.0%; specificity of 90.0%). The grey zone for CABF and VTI were 114.2-175.9 ml/min and 6.8-8.7 cm/s. The incidence of hypotension after the combined spinal-epidural anaesthesia (CSEA) was significantly higher in the Responders group 25.8% (8/31) than in the Non-Responders group 17.1(7/41) (P < 0.001). The total incidence of hypotension after CSEA of the two groups was 20.8% (15/72).

CONCLUSIONS

Ultrasound evaluation of CABF and VTI seem to be the feasible parameters to predict fluid responsiveness in parturients undergoing elective caesarean section and detecting and management of hypovolemia (fluid responsiveness) could significantly decrease incidence of hypotension after anaesthesia.

TRIAL REGISTRATION

The trial was registered at the Chinese Clinical Trial Registry (ChiCTR) ( www.chictr.org ), registration number was ChiCTR1900022327 (The website link: https://www.chictr.org.cn/showproj.html?proj=37271 ) and the date of trial registration was in April 5, 2019. This study was performed in accordance with the Declaration of Helsinki and approved by the Research Ethics Committee of Women's Hospital, Zhejiang University School of Medicine (20,180,120).

Maternal hemodynamics and computerized cardiotocography during labor with epidural analgesia

PURPOSE

To analyze the mechanisms involved in the fetal heart rate (FHR) abnormalities after the epidural analgesia in labor.

METHODS

A prospective unblinded single-center observational study on 55 term singleton pregnant women with spontaneous labor. All women recruited underwent serial bedside measurements of the main hemodynamic parameters using a non-invasive ultrasound system (USCOM-1A). Total vascular resistances (TVR), heart rate (HR), stroke volume (SV), cardiac output (CO) and arterial blood pressure were measured before epidural administration (T0), after 5 min 5 (T1) from epidural bolus and at the end of the first stage of labor (T2). FHR was continuously recorded through computerized cardiotocography before and after the procedure.

RESULTS

The starting CO was significantly higher in a subgroup of women with low TVR than in women with high-TVR group. After the bolus of epidural analgesia in the low-TVR group there was a significant reduction in CO and then increased again at the end of the first stage, in the high-TVR group the CO increased insignificantly after the anesthesia bolus, while it increased significantly in the remaining part of the first stage of labor. On the other hand, CO was inversely correlated with the number of decelerations detected on cCTG in the 1 hour after the epidural bolus while the short-term variation was significantly lower in the group with high-TVR.

CONCLUSION

Maternal hemodynamic status at the onset of labor can make a difference in fetal response to the administration of epidural analgesia.

Successful pregnancy with left ventricular assist device failure in the setting of peripartum cardiomyopathy

Pregnancy is contraindicated for women with left ventricular dysfunction due to high maternal and fetal mortality. We present a case of a pregnant 31-year-old woman with a history of heart failure due to peripartum cardiomyopathy from a previous pregnancy. She had a left ventricular assist device (LVAD) and was on warfarin due to recurrent thrombosis of her device. During her course, she had multiple cardiac complications, including thrombosis of the LVAD, which required deactivation. At 32 weeks, a cesarean section was performed due to acute decompensation, and a transthoracic echocardiogram revealed a left ventricular ejection fraction of 30% to 34%, a dilated left ventricle, and moderate global hypokinesis. This case highlights the need for coordinated care from cardiologists and maternal-fetal medicine specialists to minimize symptoms to obtain ideal outcomes for mother and infant despite LVAD deactivation.

Prevalence and risk factors of labor-onset hypertension: A multicenter study in Japan

OBJECTIVES

To investigate the prevalence and risk factors of labor-onset hypertension (LOH), defined as hypertension first detected during labor among women without hypertension prior to admission for labor.

STUDY DESIGN

In this multicenter retrospective study, clinical data of women who delivered vaginally at term between 2012 and 2018 were collected from 12 primary maternity care units. Blood pressure was measured at five time points from admission to 2 h postpartum in a total of 30,129 normotensive women at the last prenatal check-up. LOH was defined as systolic blood pressure (SBP) of ≥ 140 mmHg or diastolic blood pressure (DBP) of ≥ 90 mmHg during the first to fourth stages of labor.

MAIN OUTCOME MEASURES

Multivariate regression analyses were conducted to evaluate the risk factors of LOH and severe LOH (SBP of ≥ 160 mmHg or DBP of ≥ 110 mmHg).

RESULTS

Among the 30,129 women, 8,565 (28.4%) presented with LOH and 734 (2.4%) with severe LOH. The prevalence of LOH was the highest at the second stage of labor (21.7%) and decreased rapidly after delivery. The independent risk factors of LOH were maternal age of ≥ 35 years, pre-pregnancy body mass index of ≥ 25 kg/m², and pregnancy weight gain of ≥ 15 kg.

CONCLUSION

LOH is common, with approximately one in four women experiencing LOH during labor and early postpartum. Meanwhile, severe LOH occurred in 2.4% of the pregnancies. Closer blood pressure monitoring during labor may enable obstetric caregivers to recognize LOH in a timely manner and reduce maternal adverse outcomes, such as eclampsia and stroke.

Maternal haemodynamics during labour epidural analgesia with and without adrenaline

OBJECTIVES

Labour is one of the most painful experiences in a woman's life. Epidural analgesia using low-concentration local anaesthetics and lipophilic opioids is the gold standard for pain relief during labour. Pregnancy in general, particularly labour, is associated with changes in maternal haemodynamic variables, such as cardiac output and heart rate, which increase and peak during uterine contractions. Adrenaline is added to labour epidural solutions to enhance efficacy by stimulating the α2-adrenoreceptor. The minimal effective concentration of adrenaline was found to be 2 μg mL^-1 for postoperative analgesia. The addition of adrenaline may also produce vasoconstriction, limiting the absorption of fentanyl into the systemic circulation, thereby reducing foetal exposure. However, adrenaline may influence the haemodynamic fluctuations, possibly adding to the strain on the circulatory system. The aim of this study was to compare the haemodynamic changes after application of labour epidural analgesia with or without adrenaline 2 μg mL^-1.

METHODS

This was a secondary analysis of a single-centre, randomised double-blind trial. Forty-one nulliparous women in labour requesting epidural analgesia were randomised to receive epidural solution of bupivacaine 1 mg mL^-1, fentanyl 2 μg mL^-1 with or without adrenaline 2 μg mL^-1. The participants were monitored using a Nexfin CC continuous non-invasive blood pressure and cardiac output monitor. The primary outcomes were changes in peak systolic blood pressure and cardiac output during uterine contraction within 30 min after epidural activation. The effect of adrenaline was tested statistically using a linear mixed-effects model of the outcome variables' dependency on time, adrenaline, and their interaction.

RESULTS

After excluding three patients due to poor data quality and two due to a malfunctioning epidural catheter, 36 patients (18 in each group) were analysed. The addition of adrenaline to the solution had no significant effect on the temporal changes in peak systolic blood pressure (p=0.26), peak cardiac output (0.84), or heart rate (p=0.91). Furthermore, no significant temporal changes in maternal haemodynamics (peak systolic blood pressure, p=0.54, peak cardiac output, p=0.59, or heart rate p=0.55) were associated with epidural analgesia during 30 min after epidural activation in both groups despite good analgesia.

CONCLUSIONS

The addition of 2 μg mL^-1 adrenaline to the epidural solution is not likely to change maternal haemodynamics during labour.

Team-Based Care of Women With Cardiovascular Disease From Pre-Conception Through Pregnancy and Postpartum: JACC Focus Seminar 1/5

The specialty of cardio-obstetrics has emerged in response to the rising rates of maternal morbidity and mortality related to cardiovascular disease (CVD) during pregnancy. Women of childbearing age with or at risk for CVD should receive appropriate counseling regarding maternal and fetal risks of pregnancy, medical optimization, and contraception advice. A multidisciplinary cardio-obstetrics team should ensure appropriate monitoring during pregnancy, plan for labor and delivery, and ensure close follow-up during the postpartum period when CVD complications remain common. The hemodynamic changes throughout pregnancy and during labor and delivery should be considered with respect to the individual cardiac disease of the patient. The fourth trimester refers to the 12 weeks after delivery and is a key time to address contraception, mental health, cardiovascular risk factors, and identify any potential postpartum complications. Women with adverse pregnancy outcomes are at increased risk of long-term CVD and should receive appropriate education and longitudinal follow-up.

Point-of-Care Lung Ultrasound Pattern in Healthy Parturients: Prevalence of Pulmonary Interstitial Syndrome Following Vaginal Delivery, Elective and Unplanned Intrapartum Cesarean Delivery

BACKGROUND

Pregnancy-related cardiovascular physiologic changes increase the likelihood of pulmonary edema, with the risk of fluid extravasating into the pulmonary interstitium being potentially at a maximum during the early postpartum period. Data on the impact of labor and peripartum hemodynamic strain on lung ultrasound (LUS) are limited, and the prevalence of subclinical pulmonary interstitial syndrome in peripartum women is poorly described. The primary aim of this exploratory study was to estimate the prevalence of pulmonary interstitial syndrome in healthy term parturients undergoing vaginal (VD), elective (eCD), and unplanned intrapartum cesarean deliveries (uCD). Secondary aims were to estimate the prevalence of positive lung regions (≥3 B-lines on LUS per region) and to assess the associations between positive lung regions and possible contributing factors.

METHODS

In this prospective observational cohort study, healthy women at term undergoing VD, eCD, or uCD were enrolled. Following international consensus recommendations, a LUS examination was performed within 4 hours after delivery applying an 8-region technique. Pulmonary interstitial syndrome was defined by the presence of 2 or more positive lung regions per hemithorax. Ultrasound studies were reviewed by 2 blinded reviewers and assessed for interobserver reliability.

RESULTS

Seventy-five women were assessed (n = 25 per group). No pulmonary interstitial syndrome was found in the VD and eCD groups (each 0 of 25; 0%, 95% confidence interval [CI], 0-13.7). Pulmonary interstitial syndrome was found in 2 of 25 (8%, 95% CI, 1-26) women undergoing an uCD (P = .490 for VD versus uCD and P = .490 for eCD versus uCD). In 1 woman, this correlated clinically with the development of pulmonary edema. One or more positive lung regions were present in 5 of 25 (20%), 6 of 25 (24%), and 11 of 25 (44%) parturients following VD, eCD, and uCD, respectively (P = .136). Positive lung regions were predominantly found in lateral lung regions. The number of positive lung regions showed a weak correlation with patient age (r = 0.25, 95% CI, 0.05-0.47; P = .033). No significant association was found between LUS pattern and parity, duration of labor, labor augmentation, labor induction, estimated total intravenous fluid intake, or net intravenous fluid intake.

CONCLUSIONS

Although many focal areas of increased extravascular lung water (20%-44% prevalence) can be identified on LUS, the overall prevalence of pulmonary interstitial syndrome was 2.7% (2 of 75; 95% CI, 0.3-9.3) among healthy term parturients soon after delivery. Focal areas of positive lung water regions were weakly correlated with maternal age.

Minimally Invasive Hemodynamic Assessment during Obstetric Hysterectomy for Invasive Placentation with Epidural Anesthesia

Background

The present study aimed to describe the evolution of hemodynamic parameters over time of patients with invasive placentation during their third trimester who were delivered via cesarean section and subsequently underwent obstetric hysterectomy under epidural anesthesia.

Methods

A prospective, descriptive, longitudinal, 11-month cohort study of 43 patients aged between 18 and 37 years who presented with invasive placentation. Minimal invasive monitoring was placed before the administration of epidural anesthesia for hemodynamic parameter tracking during the cesarean section. After delivery, the patients underwent an obstetric hysterectomy. Blood loss, hemodynamic parameters, and coagulation were managed via goal-directed therapy. Parameters were compared via repeated measures ANOVA and effect size estimation (Cohen's d).

Results

The mean age of the patients was 29.2 ± 3.4 years and was moderately overweight. They had minor cardiac index variance (P=NS, no significance), vascular systemic resistance index (NS), heart rate (P=NS), and median arterial pressure (P=NS). Differences were observed in the stroke volume index (P=0.015) due to moderately higher values (d = 0.3, P=0.016) in the middle of the surgery. Patients had lower cardiac index (d = -0.36, NS) and cardiac workload requirements (d = -0.29, P=0.034) toward the completion of surgery.

Conclusion

Patients who are in their third trimester and who subsequently underwent obstetric hysterectomy under epidural anesthesia had modest surgical hemodynamic variance and reduced cardiac workload requirements toward the end of the surgery.

Postpartum blood pressure patterns in severe preeclampsia and normotensive pregnant women following abdominal deliveries: a cohort study

Objective: To determine blood pressure (BP) patterns in the immediate postpartum period in preeclampsia with severe features (sPE) and normotensive pregnant women who had cesarean deliveries (CD).Study design: The BP levels of two groups comprising 50 sPE and 90 normotensive pregnant women who had CD were measured before delivery and on days 0-3 postpartum at four time points (05:00, 08:00, 14:00, and 22:00). Soluble fms-like tyrosine kinase-1 (sFlt-1) and placental growth factor (PIGF) were measured in the maternal serum ≤48 h before delivery.Results: Antihypertensive therapy was administered to 98, 96, 82, 78, and 56% of sPE antepartum and on postpartum days 0-3, respectively. De novo postpartum hypertension (BP ≥ 140/90 mmHg) occurred in 24.4% (22/90) of the normotensive group but only one required antihypertensive therapy. The occurrence of de novo postpartum hypertension was associated with maternal weight before delivery ≥ 84.5 kg (relative risks (RR) 2.6, CI 95% 1.2-5.8, p = .017), and body mass index before delivery ≥ 33.3 kg/m2 (RR 2.9, CI 95% 1.3-6.4, p = .008). In sPE, the BP decreased between predelivery period and postpartum day 0. From days 1 to 3 postpartum, there was a continuous increase in the daily mean BPs in both groups, with average daily increments (systolic/diastolic) being 5.6/4.6 mmHg and 0.6/1.3 mmHg in the sPE and normotensive women, respectively. Patient's group and time had a significant effect on BP, p < .001. Overall, daily mean BPs were higher in the sPE than the normotensive group (p < .001). Perceived stress (p = .022), low birth weight (p = .002), 5 min Apgar score ≤ 6 (p < .001) were significantly higher in the sPE group. sFlt-1/PIGF ratio was high in the hypertensive groups: sPE versus normotensive group, p < .001; de novo postpartum hypertension versus normotensives group that remained normotensive, p = .102.Conclusion: Postpartum BP and antihypertensive requirements are important considerations in managing sPE and normotensive pregnancies. sPE is associated with increased maternal stress and poor perinatal outcomes.

Appropriate delivery method for cardiac disease pregnancy based on noninvasive cardiac monitoring

Background There are numerous significant physiological changes occurring in circulation during labor. To detect these rapid hemodynamic changes, invasive and intermittent measurement techniques are not reliable. To suggest a suitable delivery method for pregnancy with cardiac disease, this study analyzed how each delivery method influences cardiac function using a noninvasive and continuous measurement technique. Methods A prospective study was accomplished at the National Cerebral and Cardiovascular Center in Japan from October 1, 2014, to November 30, 2018. The classification of the healthy heart pregnant women was according to the delivery method: vaginal delivery (VD) without epidural anesthesia, VD with epidural anesthesia, and caesarean section (CS). The hemodynamic parameters cardiac index (CI), stroke volume index (SI), and heart rate (HR) were evaluated regularly throughout delivery by noninvasive electrical cardiometry monitor. Results Ten cases were examined for each group. CI and HR were significantly increased before VD, while the increase in CI and HR was mild in the epidural group in comparison to the nonepidural group. SI was increased toward the delivery in the epidural group, and it was constant in the nonepidural group. However, there was no alteration in the level of outcomes of the two groups. In CS, SI increased and HR decreased before delivery. After delivery, SI continued to increase, while HR did not change but CI increased. Conclusion In VD, the increase in venous circulation according to the autotransfusion is managed by increasing HR. By epidural anesthesia, the increase in HR was suppressed and SI was increased. However, as epidural anesthesia increases the vascular capacity, the level of SI outcome was comparable. In CS, the HR was decreased because of the spinal anesthesia and the SI was increased because of many factors like hydration. As there are many factors to control in CS, VD with epidural anesthesia will be the first preference for most cardiac patients.

Thoracic ultrasound evaluation and B-type natriuretic peptide value in elective cesarean section under spinal anesthesia

Background

Pregnancy-induced changes in cardiovascular status make women more susceptible to pulmonary edema. During cesarean section, to counterbalance the effect of hypotension caused by spinal anesthesia, anesthesiologists must choose between two fundamental approaches to maintain the hemodynamic state—intravenous fluids or vasopressors—and this choice will depend upon their particular opinions and experience. We aim to assess for any correlations between thoracic ultrasound A- and B-line artifacts, brain natriuretic peptide (BNP) levels, and the amount of intraoperative fluids administered.

Results

From December 2016 to August 2018, at the University-Hospital of Udine, we enrolled 80 consecutive pregnant women undergoing cesarean section. We observed a statistically significant difference in the volume of fluids administered in the first 24 h (p = 0.035) between the patients presenting B-lines in at least one basal area of their thoracic ultrasound and patients with no evident B-lines (AUC 66.4%; IC 0.49–0.83). Dividing the population on whether their BNP levels were higher or less than 20 pg/mL, no statistically significant difference was revealed with regard to fluids administered in the first 24 h (p = 0.537).

Conclusions

Thoracic ultrasound is a non-invasive and easy-to-use tool for detecting fluid intolerance in pregnant women undergoing cesarean section. BNP levels were slow to rise following the cesarean section and did not show any clear correlation with fluid volumes administered.

ACOG Practice Bulletin No. 212: Pregnancy and Heart Disease

Maternal heart disease has emerged as a major threat to safe motherhood and women's long-term cardiovascular health. In the United States, disease and dysfunction of the heart and vascular system as "cardiovascular disease" is now the leading cause of death in pregnant women and women in the postpartum period () accounting for 4.23 deaths per 100,000 live births, a rate almost twice that of the United Kingdom (). The most recent data indicate that cardiovascular diseases constitute 26.5% of U.S. pregnancy-related deaths (). Of further concern are the disparities in cardiovascular disease outcomes, with higher rates of morbidity and mortality among nonwhite and lower-income women. Contributing factors include barriers to prepregnancy cardiovascular disease assessment, missed opportunities to identify cardiovascular disease risk factors during prenatal care, gaps in high-risk intrapartum care, and delays in recognition of cardiovascular disease symptoms during the puerperium. The purpose of this document is to 1) describe the prevalence and effect of heart disease among pregnant and postpartum women; 2) provide guidance for early antepartum and postpartum risk factor identification and modification; 3) outline common cardiovascular disorders that cause morbidity and mortality during pregnancy and the puerperium; 4) describe recommendations for care for pregnant and postpartum women with preexisting or new-onset acquired heart disease; and 5) present a comprehensive interpregnancy care plan for women with heart disease.

Use of a novel non-invasive respiratory monitor to study changes in pulmonary ventilation during labor epidural analgesia

Measuring continuous changes in maternal ventilation during labor neuraxial analgesia is technically difficult. Consequently, the magnitude of pulmonary minute ventilation (MV) alterations following labor analgesia remains unknown. We hypothesized that a novel, bio-impedance based non-invasive respiratory monitor would provide this information. Furthermore, we sought to determine if an association between changes in MV and maternal temperature existed. Following calibration with a Haloscale Standard Wright Respirometer, the ExSpiron respiratory volume monitor (RVM) measured MV, respiratory rate (RR), and tidal volume (TV) in 41 term parturients receiving epidural analgesia. Simultaneously, maternal oral temperatures were recorded at pre-specified hourly intervals after epidural analgesia initiation until delivery. Cumulative MV changes were calculated as the integral of MV change over time: MV [Formula: see text], where T represents the time between epidural placement and variable measurement. The association between changes in MV and cumulative MV versus maternal temperature was determined by comparing patients whose temperature did or did not increase by ≥ 0.5 °C. After initiation of epidural analgesia, MV decreased by 11.1 ± 27.6% [mean ± SD] at 30 min, p = 0.006, and 19.8 ± 26.1% at 2 h compared to baseline (12.6 ± 7.3 L/min at baseline vs. 15.3 ± 6.3 L/min at 2 h, p < 0.001), Minute ventilation remained decreased at 4 h by 14.3 ± 31.4% (p = 0.013). The cumulative MV also decreased by 437 ± 852 L [mean ± SD], p = 0.009) at 2 h and by 795 ± 1431 L, p < 0.001) at 4 h following epidural analgesia initiation, compared to baseline. The association between changes in cumulative MV and maternal temperature following epidural placement was weak (R < 0.3); however, a decrease in MV at 30 min (p = 0.002) and cumulative MV at 2 h (p = 0.012) was observed in women whose temperature increased by at least 0.5 °C during labor. Our findings suggest that RVM can be a useful noninvasive technology to investigate pulmonary physiology during labor. The association between maternal MV and temperature change during labor analgesia deserves further investigation.Trial Registrationwww.clinicaltrials.gov (NCT02339389).

Methods and considerations concerning cardiac output measurement in pregnant women: recommendations of the International Working Group on Maternal Hemodynamics

Cardiac output (CO), along with blood pressure and vascular resistance, is one of the most important parameters of maternal hemodynamic function. Substantial changes in CO occur in normal pregnancy and in most obstetric complications. With the development of several non-invasive techniques for the measurement of CO, there is a growing interest in the determination of this parameter in pregnancy. These techniques were initially developed for use in critical-care settings and were subsequently adopted in obstetrics, often without appropriate validation for use in pregnancy. In this article, methods and devices for the measurement of CO are described and compared, and recommendations are formulated for their use in pregnancy, with the aim of standardizing the assessment of CO and peripheral vascular resistance in clinical practice and research studies on maternal hemodynamics. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Cardiac Arrhythmias and Pregnancy

PURPOSE OF REVIEWS

In this review, the challenges of managing cardiac arrhythmias and syncope in the setting of pregnancy will be discussed.

RECENT FINDINGS

Arrhythmias in pregnancy are increasing, as diagnostic and therapeutic options have advanced and women are older at the time of gestation. Atrial fibrillation has become the most common arrhythmia in pregnancy. Inherited arrhythmia has become a more common entity, with advances in treatments and genetic testing, and require specialized treatments in pregnancy. The majority of arrhythmias in pregnancy are benign. The potential risk of increased cardiac morbidity and mortality exists for mother and fetus, especially in women with structural heart disease, which is becoming increasingly common. Early evaluation, diagnosis, and appropriate treatment are necessary to achieve optimal outcomes for both mother and fetus.