Fetal outcome in the critically ill pregnant woman

Acute Respiratory Failure in Pregnancy

Respiratory failure may affect up to 1 in 500 pregnancies, due to pregnancy-specific conditions, conditions aggravated by the pregnant state, or other causes. Management during pregnancy is influenced by altered maternal physiology, and the presence of a fetus influencing imaging, and drug therapy choices. Few studies have addressed the approach to invasive mechanical ventilatory management in pregnancy. Hypoxemia is likely harmful to the fetus, but precise targets are unknown. Hypocapnia reduces uteroplacental circulation, and some degree of hypercapnia may be tolerated in pregnancy. Delivery of the fetus may be considered to improve maternal respiratory status but improvement does not always occur.

Pregnancy and Severe ARDS with COVID-19: Epidemiology, Diagnosis, Outcomes and Treatment

Pregnancy-related acute respiratory distress syndrome (ARDS) is fast becoming a growing and clinically relevant subgroup of ARDS amidst global outbreaks of various viral respiratory pathogens that include H1N1-influenza, severe acute respiratory syndrome (SARS), middle east respiratory syndrome (MERS), and the most recent COVID-19 pandemic. Pregnancy is a risk factor for severe viral-induced ARDS and commonly associated with poor maternal and fetal outcomes including fetal growth-restriction, preterm birth, and spontaneous abortion. Physiologic changes of pregnancy further compounded by mechanical and immunologic alterations are theorized to impact the development of ARDS from viral pneumonia. The COVID-19 sub-phenotype of ARDS share overlapping molecular features of maternal pathogenicity of pregnancy with respect to immune-dysregulation and endothelial/microvascular injury (i.e., preeclampsia) that may in part explain a trend toward poor maternal and fetal outcomes seen with severe COVID-19 maternal infections. To date, current ARDS diagnostic criteria and treatment management fail to include and consider physiologic adaptations that are unique to maternal physiology of pregnancy and consideration of maternal-fetal interactions. Treatment focused on lung-protective ventilation strategies have been shown to improve clinical outcomes in adults with ARDS but may have adverse maternal-fetal interactions when applied in pregnancy-related ARDS. No specific pharmacotherapy has been identified to improve outcomes in pregnancy with ARDS. Adjunctive therapies aimed at immune-modulation and anti-viral treatment with COVID-19 infection during pregnancy have been reported but data in regard to its efficacy and safety is currently lacking.

Frequency and Results of Pregnancy Screening in Critically Ill Adolescents in Multiple Health Care Organizations

PURPOSE

Adolescent females may undergo pregnancy screening while receiving critical care services, but the frequency and results are unknown. The objectives of this study are to evaluate patient characteristics, pregnancy screening frequency, and rate of positive pregnancy screens in adolescent females of childbearing age who require critical care services. We hypothesize that when adolescent pregnancy screening is performed in the critical care setting, it occurs in a higher frequency in older subjects.

METHODS

This is a multicenter retrospective observational cohort study utilizing TriNetX, an electronic health record database. The following electronic health record data were collected and evaluated in adolescent females aged 12-18 years and billed for critical care services: age, race, ethnicity, diagnostic codes, selected radiology and surgical procedure codes, number of deaths, pregnancy screening laboratory codes, and pregnancy screening results.

RESULTS

A total of 5,241 subjects (2,242 [42.8%] subjects for whom pregnancy screen was noted and 2,999 [57.2%] subjects for whom it was not noted) were included in this study. Subjects aged 15-18 years (odds ratio = 1.56, 95% confidence interval = 1.38-1.77, p value < .0001) and had Hispanic or Latina ethnicity (odds ratio = 1.46, 95% confidence interval = 1.28-1.66, p value < .0001) had a higher association with pregnancy screening. A positive pregnancy screen was identified in 18 (0.8%) subjects.

DISCUSSION

In our study, positive pregnancy screens were infrequent, not all subjects were screened, and there was an association between pregnancy screening and ethnicity. Because of the potential for screening bias, this study suggests that clinicians should strongly consider routine pregnancy screening for all females of childbearing age and that hospital policies should require this type of screening.

Placenta in the Critically Ill Mother

The placenta is a temporary, multifunctional organ composed of both maternal and fetal components. It maintains homeostasis to ensure the growth of the fetus and well-being of the mother. Abnormalities in placental development have been known to be responsible for several disorders of pregnancy. Conditions coincident with pregnancy can upset the homeostasis and result in critical illness, which can greatly impact placental function and in turn affect the fetus. Decreased blood flow, acidemia, hypercarbia, and hypoxia seen in critically ill pregnant mothers can result in fetal death. Understanding the physiological changes and functioning of the maternal-fetal-placental unit will aid in better management of critically ill mothers.

How to cite this article

Taggarsi DA, Krishna B. Placenta in the Critically Ill Mother. Indian J Crit Care Med 2021;25(Suppl 3):S200-S205.

A Detailed Review of Critical Care Considerations for the Pregnant Cardiac Patient

Maternal cardiovascular disease is a leading cause of maternal death worldwide and recently, maternal mortality has increased secondary to cardiovascular causes. Maternal admissions to critical care encompass 1%-2% of all critical care admissions, and although not common, the management of the critically ill pregnant patient is complex. Caring for the critically ill pregnant cardiac patient requires integration of pregnancy-associated physiologic changes, understanding pathophysiologic disease states unique to pregnancy, and a multidisciplinary approach to timing around delivery as well as antenatal and postpartum care. Herein we describe cardiorespiratory changes that occur during pregnancy and the differential diagnosis for cardiorespiratory failure in pregnancy. Cardiorespiratory diseases that are either associated or exacerbated by pregnancy are highlighted with emphasis on perturbations secondary to pregnancy and appropriate management strategies. Finally, we describe general management of the pregnant cardiac patient admitted to critical care.

Women of reproductive age in a tertiary intensive care unit: indications, outcome and the impact of pregnancy-a retrospective cohort study

Background

To evaluate the indications for admission and mortality rates of women of reproductive age admitted to a tertiary Intensive Care Unit (ICU) and to compare the outcomes of obstetric and non-obstetric admissions.

Methods

A retrospective cohort study was performed, including all women aged 17–41 years admitted to a level 3 ICU in the Netherlands, between January 1, 2000 and January 1, 2016. Primary outcome was indication for admission and mortality. Mortality, length of stay (LOS), need for mechanical ventilation and APACHE II score were compared between obstetric and non-obstetric admissions. The obstetric group was further analyzed for maternal and perinatal outcomes.

Results

3461 women (median age 32 years) were included, with an overall mortality rate of 13.3%. The obstetric group consisted of 265 women (7.7%). The non-obstetric group (n = 3196) was admitted most often for cardiovascular disease (19.6%), followed by oncologic disease (15%). Mortality was the highest in women with oncologic disease (23.9%). The obstetric group had lower mortality compared to the non-obstetric group (4.9% vs. 14%, p < 0.001), despite higher APACHE II score (14 vs. 11, p < 0.001) and a higher ventilation rate (47.9% vs. 39%, p = 0.004). Major surgical or endovascular interventions, besides caesarean section, were performed in 46% of the obstetric group. Perinatal death occurred in 17.2% and of the surviving infants, 63.2% were born preterm and 45.1% required Neonatal Intensive Care Unit admission.

Conclusions

Cardiovascular disease is the most important indication for admission and oncologic disease is associated with highest mortality in women of reproductive age. Obstetric patients constitute a small percentage of all ICU admissions in a tertiary ICU center. They have lower mortality rates than non-obstetric young female patients, despite a more severe initial presentation. Nevertheless lasting maternal morbidity and perinatal mortality and morbidity is frequent.

Distinct maternal and fetal pregnancy outcomes in women with sickle cell disease can be predicted using routine clinical and laboratory data

We aimed to identify risk factors for adverse outcomes in pregnancies of women with sickle cell disease (SCD) and develop risk prediction models. Models were derived from a retrospective cohort of pregnant women with SCD and constructed using generalised estimating equation logistic regression, with clustering by woman. Maternal event(s) consisted of acute anaemia; cardiac, pulmonary, hepatobiliary, musculoskeletal, skin, splenic, neurological or renal complications, multi‐organ failure, venous thromboembolism, admission‐requiring vaso‐occlusive events (VOE), red cell transfusion, mortality or hypertensive disorder of pregnancy. Fetal events included preterm birth, small‐for‐gestational‐age or perinatal mortality. Of 199 pregnancies, 71% and 45% resulted in adverse maternal and fetal outcomes respectively. Low first‐trimester haemoglobin, admission‐requiring VOE in the year before pregnancy, multiple transfusions before pregnancy, SCD genotype and previous cardiac complications predicted maternal risk. Younger age and SCD genotype allowed early prediction of fetal risk (model‐F1). Adding maternal event(s) and high lactate dehydrogenase enabled re‐assessment of fetal risk with advancing gestation (model‐F2). Models were well calibrated and moderately discriminative for maternal outcome (c‐statistic 0·81, cross‐validated value 0·79) and fetal outcome (model‐F1 c‐statistic 0·68, cross‐validated value 0·65; model‐F2 c‐statistic 0·72, cross‐validated value 0·68). The models will allow early identification of women with SCD at high risk of adverse events, permitting early targeted interventions and ongoing fetal risk re‐assessment enabling intensification of surveillance and optimisation of delivery timing.

Prone ventilation in a pregnant patient with scrub typhus-induced acute respiratory distress syndrome

A 23-year-old primigravida at 20 weeks of gestation presented to our hospital with undifferentiated febrile illness and severe acute respiratory distress syndrome. She was intubated in the emergency department and transferred to the intensive care unit. Initial treatment included ventilatory care, vasopressor support and broad-spectrum antibiotics. Based on a positive PCR assay for scrub typhus, she was treated with intravenous doxycycline and azithromycin. Despite reduction in fever, her oxygenation further declined. Following a risk-benefits assessment, we decided to ventilate her in prone position for 8 hours a day for three consecutive days using a checklist-based protocol. Her oxygenation indices and lung compliance markedly improved over this period, and she was extubated a day later. She was eventually discharged home after 1 week.

Severe Maternal Morbidity and Infant Mortality in Canada

BACKGROUND

Severe maternal morbidity (SMM) comprises an array of conditions and procedures denoting an acutely life-threatening pregnancy-related condition. SMM may further compromise fetal well-being. Empirical data are lacking about the relation between SMM and infant mortality.

METHODS

This population-based cohort study included 1 892 857 singleton births between 2002 and 2017 in Ontario, Canada, within a universal health care system. The exposure was SMM as an overall construct arising from 23 weeks' gestation up to 42 days after the index delivery. The primary outcome was infant mortality from birth to 365 days. Multivariable modified Poisson regression generated relative risks and 95% confidence intervals (CIs), adjusted for maternal age, income, rurality, world region of origin, diabetes mellitus, and chronic hypertension.

RESULTS

Infant mortality occurred among 174 of 19 587 live births with SMM (8.9 per 1000) vs 5289 of 1 865 791 live births without SMM (2.8 per 1000) (an adjusted relative risk of 2.93 [95% CI 2.51-3.41]). Of 19 587 pregnancies with SMM, 4523 (23.1%) had sepsis. Relative to births without SMM, the adjusted odds ratio for infant death from sepsis was 1.95 (95% CI 1.10-3.45) if SMM occurred without maternal sepsis and 6.36 (95% CI 3.50-11.55) if SMM included sepsis.

CONCLUSIONS

SMM confers a higher risk of infant death. There is also coupling tendency (concurrent event of interest) between SMM with sepsis and infant death from sepsis. Identification of preventable SMM indicators, as well as the development of strategies to limit their onset or progression, may reduce infant mortality.

Special Populations: Disaster Care Considerations in Chronically Ill, Pregnant, and Morbidly Obese Patients

Special populations, which include the morbidly obese and patients with chronic, complex medical conditions that require long-term health care services and infrastructure, are at increased risk for morbidity and mortality when these services are disrupted during a disaster. Past experiences have identified significant challenges in restoring necessary care services to these patients following major environmental events. This article describes the impact of disasters on special populations, provides a framework for future disaster preparation and planning, and identifies areas in need of further research. Gravid patients, who are often overlooked in disaster planning and preparation, are also discussed.

Development of a Core Outcome Set for research on critically ill obstetric patients: A study protocol

Background

Current data on critical illness during pregnancy are insufficient for evidence-based decision making. Core outcome sets are promoted to improve reporting of outcomes important to decision makers. We aim to develop a Core Outcome Set for research on critically ill obstetric patients (COSCO study).

Methods

We will perform a systematic review of studies on critical illness in pregnancy and focus groups or interviews with women who were critically ill while being pregnant. These data will inform an international Delphi survey where stakeholders will rank proposed outcomes. Selected outcomes will be brought forward to a consensus meeting where core outcomes will be defined. We will then complete a second consensus process to define measures for each core outcome.

Conclusion

The Core Outcome Set on Critically ill Obstetric patients study aims to develop a set of core outcomes to be part of all studies on critically ill obstetric patients. Implementation of this core outcome set will help improve future research efforts.Trial registration: This study is registered on the COMET-initiative website (COS #916). This systematic review is registered on PROSPERO (CRD #42017071944).

Impact of violence against women on severe acute maternal morbidity in the intensive care unit, including neonatal outcomes: a case-control study protocol in a tertiary healthcare facility in Lima, Peru

INTRODUCTION

Preventing and reducing violence against women (VAW) and maternal mortality are Sustainable Development Goals. Worldwide, the maternal mortality ratio has fallen about 44% in the last 25 years, and for one maternal death there are many women affected by severe acute maternal morbidity (SAMM) requiring management in the intensive care unit (ICU). These women represent the most critically ill obstetric patients of the maternal morbidity spectrum and should be studied to complement the review of maternal mortality. VAW has been associated with all-cause maternal deaths, and since many women (30%) endure violence usually exerted by their intimate partners and this abuse can be severe during pregnancy, it is important to determine whether it impacts SAMM. Thus, this study aims to investigate the impact of VAW on SAMM in the ICU.

METHODS AND ANALYSIS

This will be a prospective case-control study undertaken in a tertiary healthcare facility in Lima-Peru, with a sample size of 109 cases (obstetric patients admitted to the ICU) and 109 controls (obstetric patients not admitted to the ICU selected by systematic random sampling). Data on social determinants, medical and obstetric characteristics, VAW, pregnancy and neonatal outcome will be collected through interviews and by extracting information from the medical records using a pretested form. Main outcome will be VAW rate and neonatal mortality rate between cases and controls. VAW will be assessed by using the WHO instrument. Binary logistic followed by stepwise multivariate regression and goodness of fit test will assess any association between VAW and SAMM.

ETHICS AND DISSEMINATION

Ethical approval has been granted by the La Trobe University, Melbourne-Australia and the tertiary healthcare facility in Lima-Peru. This research follows the WHO ethical and safety recommendations for research on VAW. Findings will be presented at conferences and published in peer-reviewed journals.

A Standardized Approach to Electronic Fetal Monitoring in Critical Care Obstetrics

From the periphery, pregnancy is a common event in women of childbearing age. Normal anatomic and physiologic adaptations occur and, in most cases, will result in ideal maternal-fetal outcomes. Yet, every day, obstetric clinicians are facing complex pregnancies with complicated life-threatening conditions or coexisting medical and surgical problems that not only alter maternal physiology but also impact fetal survival. A challenge in this population is individualizing maternal-fetal care in critical care women while integrating medical-surgical specialties in creating an interdisciplinary team with similar management goals. Questions frequently arise concerning admission criteria, location of care, as well as type and mix of personnel. Furthermore, how to simultaneously manage a critically ill parturient while monitoring a viable fetus is often obscured. This article focuses on crucial fetal monitoring concepts using a standardized approach to interpretation and management in pregnancies managed in an intensive care environment. Application of fetal monitoring during surgical procedures, during perimortem cesarean birth, and in women who have irreversible loss of brain function is included.

Measurement properties of comorbidity indices in maternal health research: a systematic review

Background

Maternal critical illness occurs in 1.2 to 4.7 of every 1000 live births in the United States and approximately 1 in 100 women who become critically ill will die. Patient characteristics and comorbid conditions are commonly summarized as an index or score for the purpose of predicting the likelihood of dying; however, most such indices have arisen from non-pregnant patient populations. We sought to systematically review comorbidity indices used in health administrative datasets of pregnant women, in order to critically appraise their measurement properties and recommend optimal tools for clinicians and maternal health researchers.

Methods

We conducted a systematic search of MEDLINE and EMBASE to identify studies published from 1946 and 1947, respectively, to May 2017 that describe predictive validity of comorbidity indices using health administrative datasets in the field of maternal health research. We applied a methodological PubMed search filter to identify all studies of measurement properties for each index.

Results

Our initial search retrieved 8944 citations. The full text of 61 articles were identified and assessed for final eligibility. Finally, two eligible articles, describing three comorbidity indices appropriate for health administrative data remained: The Maternal comorbidity index, the Charlson comorbidity index and the Elixhauser Comorbidity Index. These studies of identified indices had a low risk of bias. The lack of an established consensus-building methodology in generating each index resulted in marginal sensibility for all indices. Only the Maternal Comorbidity Index was derived and validated specifically from a cohort of pregnant and postpartum women, using an administrative dataset, and had an associated c-statistic of 0.675 (95% Confidence Interval 0.647–0.666) in predicting mortality.

Conclusions

Only the Maternal Comorbidity Index directly evaluated measurement properties relevant to pregnant women in health administrative datasets; however, it has only modest predictive ability for mortality among development and validation studies. Further research to investigate the feasibility of applying this index in clinical research, and its reliability across a variety of health administrative datasets would be incrementally helpful. Evolution of this and other tools for risk prediction and risk adjustment in pregnant and post-partum patients is an important area for ongoing study.

Electronic supplementary material

The online version of this article (10.1186/s12884-017-1558-3) contains supplementary material, which is available to authorized users.

Maternal and Perinatal Exposures Are Associated With Risk for Pediatric-Onset Multiple Sclerosis

OBJECTIVE

To determine if prenatal, pregnancy, or postpartum-related environmental factors are associated with multiple sclerosis (MS) risk in children.

METHODS

This is a case-control study of children with MS or clinically isolated syndrome and healthy controls enrolled at 16 clinics participating in the US Network of Pediatric MS Centers. Parents completed a comprehensive environmental questionnaire, including the capture of pregnancy and perinatal factors. Case status was confirmed by a panel of 3 pediatric MS specialists. Multivariable logistic regression analyses were used to determine association of these environmental factors with case status, adjusting for age, sex, race, ethnicity, US birth region, and socioeconomic status.

RESULTS

Questionnaire responses were available for 265 eligible cases (median age 15.7 years, 62% girls) and 412 healthy controls (median age 14.6, 54% girls). In the primary multivariable analysis, maternal illness during pregnancy was associated with 2.3-fold increase in odds to have MS (95% confidence interval [CI] 1.20-4.21, P = .01) and cesarean delivery with 60% reduction (95% CI 0.20-0.82, P = .01). In a model adjusted for these variables, maternal age and BMI, tobacco smoke exposure, and breastfeeding were not associated with odds to have MS. In the secondary analyses, after adjustment for age, sex, race, ethnicity, and socioeconomic status, having a father who worked in a gardening-related occupation (odds ratio [OR] 2.18, 95% CI 1.14-4.16, P = .02) or any use in household of pesticide-related products (OR 1.73, 95% CI 1.06-2.81, P = .03) were both associated with increased odds to have pediatric MS.

CONCLUSION

Cesarean delivery and maternal health during pregnancy may influence risk for pediatric-onset MS. We report a new possible association of pesticide-related environmental exposures with pediatric MS that warrants further investigation and replication.

[Effect of heat exposure in the second trimester of pregnancy on intrauterine growth of fatal rat and the expression of HSP70, Bax and Bcl-2 of placenta]

OBJECTIVE

To investigate the effect of heat exposure during the second week of pregnancy on placental development and intrauterine growth of fetal rats.

METHODS

24 pregnant rats were either exposed or not to a temperature of 35∓1 degrees celsius; during the second week of pregnancy. The body weight gain of the pregnant rats was measured regularly, and in late pregnancy, the pregnant rats were dissected and the number, weight, length, tail length, appearance of the offspring rats, number of live and still births, and the placental weight were recorded. The expressions of HSP70, Bax and Bcl-2 in the placenta were determined.

RESULTS

Compared with the control group, the pregnant rats in heat exposure group had significantly lower body weight at the end of pregnancy and gestational weight gain, and the body weight, body length and tail length of the offspring rats were also significantly lower or smaller (P<0.05). The placental weight was comparable between the two groups. The placental expressions of HSP70,Bax,and Bcl-2 were significantly higher in the heat exposure group than in the control group (P<0.05).

CONCLUSION

Heat exposure during the second trimester of pregnancy has adverse effects on placental development and intrauterine growth of the fetal rats by inducing heat shock response of placental tissue and apoptosis of the placental cells.

Acute respiratory failure in pregnancy

Respiratory failure affects up to 0.2% of pregnancies, more commonly in the postpartum period. Altered maternal respiratory physiology affects the assessment and management of these patients. Respiratory failure may result from pregnancy-specific conditions such as preeclampsia, amniotic fluid embolism or peripartum cardiomyopathy. Pregnancy may increase the risk or severity of other conditions, including thromboembolism, asthma, viral pneumonitis, and gastric acid aspiration. Management during pregnancy is similar to the nonpregnant patient. Endotracheal intubation in pregnancy carries an increased risk, due to airway edema and rapid oxygen desaturation following apnea. Few data are available to direct prolonged mechanical ventilation in pregnancy. Chest wall compliance is reduced, perhaps permitting slightly higher airway pressures. Optimizing oxygenation is important, but data on the use of permissive hypercapnia are limited. Delivery of the fetus does not always improve maternal respiratory function, but should be considered if benefit to the fetus is anticipated.

Mechanical ventilation in critically-ill pregnant women: a case series

BACKGROUND

Approximately 0.1-0.2% of pregnancies are complicated by respiratory failure requiring mechanical ventilatory support, but few data exist to inform clinical management. This study aimed to characterize current practice and the effect of delivery on respiratory function.

METHODS

A retrospective review was performed of pregnant women who received mechanical ventilation for more than 24h, from four intensive care units in institutions with large-volume obstetric units.

RESULTS

Data were collected from 29 patients with a mean gestation at intensive care unit admission of 25.3 ± 6 weeks. Tidal volumes were 7.7 ± 1.7 mL/kg predicted body weight. Estimated respiratory system compliance was reduced, but was higher in four patients ventilated for neurological conditions without lung disease. Three maternal and three neonatal deaths occurred. Ten patients delivered while on ventilatory support: one spontaneous delivery, four for obstetric indications and five for worsening maternal condition. Following delivery of these 10 patients, three demonstrated a greater than 50% decrease in oxygenation index and five a greater than 50% increase in compliance. No characteristics identified which patients may benefit from delivery.

CONCLUSIONS

Review of current practice in four centers suggests that mechanical ventilation in pregnant patients follows usual guidelines applicable to non-pregnant patients. Delivery was associated with modest improvement in maternal respiratory function in some patients. Any potential benefit of delivery in improving maternal physiology must be weighed against the stress of delivery. The risks of premature birth for the fetus must be weighed against continued exposure to maternal hypoxemia and hypotension.