How safe is the prone position in acute respiratory distress syndrome at late pregnancy?

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.

[Prone position in the third trimester of pregnancy during the COVID-19 era: a transdisciplinary approach.]

There is very limited evidence regarding the use of prone position as part of the treatment of severe ARDS in pregnant patients. Currently, recommendations for invasive ventilatory management in this population are very scarce and are based on the extrapolation of conclusions obtained in studies of non-pregnant patients. The available literature asserts that the anatomy and physiology of the pregnant woman undergoes complex adaptive changes that must be considered during invasive ventilatory support and prone position. With prone ventilation, the benefits obtained for the couple far outweigh the eventual risks. Adequate programming of the mechanical ventilator correlates with a clear and simple concept: individualization of support. In any case, the decision on the timing of termination of pregnancy should be based on adequate multidisciplinary clinical judgment and should be supported by strict monitoring of the product.

COVID-19 and Pregnancy: An Updated Review about Evidence-Based Therapeutic Strategies

The COVID-19 pandemic posed a significant challenge for clinicians in managing pregnant women, who were at high risk of virus transmission and severe illness. While the WHO declared in May 2023 that COVID-19 is no longer a public health emergency, it emphasized that it remains a global health threat. Despite the success of vaccines, the possibility of new pandemic waves due to viral mutations should be considered. Ongoing assessment of the safety and effectiveness of pharmacological therapies is crucial in clinical practice. This narrative review summarizes the evidence-based therapeutic strategies for pregnant women with COVID-19, considering over three years of pandemic experience. The review discusses the safety and effectiveness of various drug regimens (antivirals, anticoagulants, corticosteroids, immunoglobulins, monoclonal antibodies, and therapeutic gases) and procedures (prone positioning and extracorporeal membrane oxygenation). Drugs with contraindications, inefficacy during pregnancy, or unknown adverse effects were excluded from our evaluation. The aim is to provide healthcare professionals with a comprehensive guide for managing pregnant women with COVID-19 based on lessons learned from the pandemic outbreak.

Acute Respiratory Distress Syndrome in Pregnancy: Updates in Principles and Practice

Acute respiratory failure occurs in 0.05% to 0.3% of pregnancies and is precipitated by pulmonary and nonpulmonary insults. Acute respiratory distress syndrome (ARDS) is the rapid onset of hypoxemic respiratory failure associated with bilateral pulmonary opacities on chest imaging attributed to noncardiogenic pulmonary edema. The pathophysiological features of ARDS include hypoxemia, diminished lung volumes, and decreased lung compliance. While there is a paucity of data concerning ARDS in the pregnant individual, management principles do not vary significantly between pregnant and nonpregnant patients. The following review will discuss the diagnosis and management of the pregnant patient with ARDS.

Prone Positioning for Acute Hypoxemic Respiratory Failure and ARDS: A Review

Prone positioning is an immediately accessible, readily implementable intervention that was proposed initially as a method for improvement in gas exchange > 50 years ago. Initially implemented clinically as an empiric therapy for refractory hypoxemia, multiple clinical trials were performed on the use of prone positioning in various respiratory conditions, cumulating in the landmark Proning Severe ARDS Patients trial, which demonstrated mortality benefit in patients with severe ARDS. After this trial and the corresponding meta-analysis, expert consensus and societal guidelines recommended the use of prone positioning for the management of severe ARDS. The ongoing COVID-19 pandemic has brought prone positioning to the forefront of medicine, including widespread implementation of prone positioning in awake, spontaneously breathing, nonintubated patients with acute hypoxemic respiratory failure. Multiple clinical trials now have been performed to investigate the safety and effectiveness of prone positioning in these patients and have enhanced our understanding of the effects of the prone position in respiratory failure. In this review, we discuss the physiologic features, clinical outcome data, practical considerations, and lingering questions of prone positioning.

Prone Positioning: A Safe and Effective Procedure in Pregnant Women Presenting with Severe Acute Respiratory Distress Syndrome

Prone positioning (PP) improves oxygenation and survival in patients with severe acute respiratory distress syndrome (ARDS). Data regarding feasibility and effectiveness of PP in pregnancy are lacking. This subgroup analysis of a cohort study that included mechanically ventilated pregnant women presenting with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-induced ARDS who underwent PP aims to assess the efficacy and safety of PP. Ventilatory and gasometric parameters were evaluated at baseline (T0) and in prone (T1) and supine (T2) positions. Obstetric outcomes were also assessed. Sixteen cases at an average of 27.0 (22.0−31.1) gestational weeks of pregnancy were included. Obesity and hypertension were frequent comorbidities. PP was associated with a >20% increase in PaO2 levels and in PaO2/FiO2 ratios in 50% and 100% of cases, respectively. The PaO2/FiO2 ratio increased 76.7% (20.5−292.4%) at T1 and 76.9% (0−182.7%) at T2. PP produced sustained improvements in mean PaO2/FiO2 ratio (p < 0.001) and PaCO2 level (p = 0.028). There were no cases of emergency delivery or suspected fetal distress in pregnancies ≥25 weeks during the 24 h period following PP. PP is safe and feasible during pregnancy, improving PaO2/FiO2 ratios and helping to delay preterm delivery in severe ARDS.

Treatment of pregnant and early postpartum women with severe and critical COVID-19: experience at a tertiary center

BACKGROUND

The management of acute respiratory failure during pregnancy is a poorly defined issue in the literature, especially regarding the use of the prone position and the appropriate time for delivery. This study describes our experience in treating pregnant and postpartum women with severe or critical coronavirus disease 2019 (COVID-19).

MATERIALS AND METHODS

This descriptive retrospective study included 25 pregnant and 4 postpartum women admitted to an ICU due to respiratory complications from COVID-19 from June 2020 to August 2021.

RESULTS

The mean maternal age was 33.6 years, and the median gestational age (GA) at admission was 33 weeks. Obesity was the most common comorbidity. The median time between symptom onset and ICU admission was 10 days, while the median length of ICU stay was 14 days. Invasive mechanical ventilation (IMV) was required in 16 (55.2%) patients for a median time of 16.5 days. Prone positioning (PP) was performed in 68.7% of the patients on IMV, and resulted in an expressive increase in arterial oxygen partial pressure to fractional inspired oxygen (PaO2/FiO2 ratio). Eleven (44%) pregnant women delivered during their ICU stay for obstetric or fetal reasons: of these, 2 (18%) developed postpartum hemorrhagic shock and 1 (9%) developed abdominal wall infection. None of the 25 pregnant women underwent delivery due to acute respiratory failure or in an attempt to avoid intubation. There were 2 fetal deaths, but no maternal or neonatal deaths.

CONCLUSION

We observed favorable outcomes in pregnant and postpartum women with severe and critical COVID-19 admitted to our institution. This finding reinforces the effectiveness of PP in the treatment of hypoxemic respiratory failure secondary to COVID-19 in pregnant women undergoing IMV, and suggests that gestation should only be interrupted in cases of obstetric and fetal complications, provided the patient is stable, or when hypoxemia is refractory to PP.

Acute Respiratory Distress Syndrome in Pregnancy

Acute respiratory distress syndrome (ARDS) is a clinical syndrome characterized by several clinical features and pathological responses involving the respiratory system primarily. Infections (viral), sepsis, and massive transfusion are the commonest causes of ARDS during pregnancy. The majority of them recover with noninvasive ventilatory (NIV) support. NIV is safe in pregnancy provided the center is experienced and has a protocolized patient care pathway. Parturients requiring invasive mechanical ventilation are best managed in experienced centers. PaO₂/FiO₂ targets are higher in parturients compared to nonpregnant patients. Permissive hypercapnia is not a safe option in pregnancy. In severe ARDS with refractory hypoxemia, prone ventilation is a safe option. However, it has to be done in experienced centers. Venovenous ECMO is a safe alternative option in pregnant women with refractory hypoxemia, and delivery has been prolonged to a safe viable age on ECMO. The decision to deliver and the mode of delivery have to be a multidisciplinary decision; primary criterion is maternal survival. Postdelivery, establishing maternal bonding while in ventilatory support facilitates early weaning and minimizes lactation failure.

Use of the prone position in pregnant women with COVID-19 or other health conditions

OBJECTIVE

to analyze, in the scientific literature, the knowledge available on the use of the prone position in pregnant women diagnosed with COVID-19 or other health conditions.

METHOD

an integrative literature review developed through the following guiding question: What is the scientific knowledge available on the use of the prone position in pregnant women with COVID-19 or other health conditions? The search for studies was carried out in eight databases.

RESULTS

using the prone position in pregnant women with Acute Respiratory Distress syndrome allowed for improvements in lung compliance and oxygenation. It also allowed reducing uterine compression on the maternal large vessels, and a reduction in blood pressure was observed in pregnant women with pre-eclampsia. The prone position was also safe in the surgical management of pregnant patients. In addition, the following conditions stood out as disadvantages related to the prone position in pregnant women: possibility of aortocaval compression, causing severe hypotension, and inability to easily monitor fetal status or to perform emergency Cesarean sections.

CONCLUSION

the prone position was considered safe, reliable and comfortable for its use in the clinical management of pregnant women, where specific care measures must be taken to avoid compression of gravid abdomen, as well as fetal monitoring is important to detect placental circulation impairment.

Mechanical ventilation and prone positioning in pregnant patients with severe COVID-19 pneumonia: experience at a quaternary referral center

BACKGROUND

We present the care of 17 consecutive pregnant patients who required mechanical ventilation for Coronavirus disease 2019 (COVID-19) pneumonia at a quaternary referral center in the United States. We retrospectively describe the management of these patients, maternal and fetal outcomes, as well as the feasibility of prone positioning and delivery.

METHODS

Between March 2020 and June 2021, all pregnant and postpartum patients who were mechanically ventilated for COVID-19 pneumonia were identified. Details of their management including prone positioning, maternal and neonatal outcomes, and complications were noted.

RESULTS

Seventeen pregnant patients required mechanical ventilation for COVID-19. Thirteen patients received prone positioning, with a total of 49 prone sessions. One patient required extracorporeal membrane oxygenation. All patients in this series survived until at least discharge. Nine patients delivered while mechanically ventilated, and all neonates survived, subsequently testing negative for SARS-CoV-2. There was one spontaneous abortion. Four emergent cesarean deliveries were prompted by refractory maternal hypoxemia or non-reassuring fetal heart rate after maternal intubation.

CONCLUSIONS

Overall, maternal and neonatal survival were favorable even in the setting of severe COVID-19 pneumonia requiring mechanical ventilation. Prone positioning was well tolerated although the impact of prone positioning or fetal delivery on maternal oxygenation and ventilation are unclear.

Critical COVID-19 in a pregnant patient who presented in starvation ketoacidosis with a background history of acrorenal syndrome

A primiparous woman in her late 30s at 28+1 weeks’ gestation presented with a 3-day history of abdominal pain, loss of appetite, nausea and vomiting and was diagnosed with starvation ketoacidosis. A routine admission swab returned positive for COVID-19. She had been diagnosed with acrorenal syndrome from birth. Three days post admission, she deteriorated rapidly into respiratory failure requiring intubation and ventilation. She was treated with dexamethasone, prophylactic enoxaparin, a course of piperacillin/tazobactam followed by meropenem and fluconazole and 8 cycles of proning. An emergency caesarean section was performed on day 12 of hospital admission at 29+5 weeks’ gestation to improve maternal oxygenation and ventilation. The baby had deformities consistent with acrorenal syndrome but no evidence of COVID-19. She spent 23 days in the intensive care unit. Our case describes an unusual presentation of COVID-19, the challenges in managing critically ill pregnant patients along with a rare background history of acrorenal syndrome.

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.

Multiprofessional perinatal care in a pregnant patient with acute respiratory distress syndrome due to COVID-19

Background

The coronavirus disease (COVID-19) pandemic has caused ongoing challenges in health services worldwide. Despite the growing body of literature on COVID-19, reports on perinatal care in COVID-19 cases are limited.

Case presentation

We describe a case of severe acute respiratory distress syndrome (ARDS) in a 36-year-old G5/P2 pregnant woman with morbid obesity, confirmed severe acute respiratory syndrome coronavirus 2 infection, and fulminant respiratory failure. At 28^+ 1 gestational weeks, the patient delivered an uninfected newborn. Using ImmunoCAP ISAC® technology, we found no immunoglobulin (Ig) M antibodies, suggesting that no mother-to-child viral transmission occurred during pregnancy or delivery. The maternal respiratory state improved rapidly after delivery; both maternal and neonatal outcomes were encouraging given the early gestational age and fulminant course of respiratory failure in our patient.

Conclusions

The management of ARDS in pregnant women with COVID-19 is complex and requires an individualized, multidisciplinary approach, while considering maternal and fetal outcomes.

Conscious prone positioning in a pregnant patient with COVID-19 respiratory distress: A case report and review

Prone positioning has been used for decades to improve oxygenation in patients with acute respiratory distress syndrome. With the COVID-19 pandemic there has been a growing emphasis on the utilization of prone positioning for non-intubated patients as a means of preventing invasive ventilation and improving outcomes. In this case report, a patient is presented with acute hypoxemic respiratory failure in late pregnancy who experienced significant improvements in oxygenation with prone positioning. Additionally, the physiology of prone positioning is reviewed, as well as its mechanism and safety in pregnancy.

Awake Proning as an Adjunctive Therapy for Refractory Hypoxemia in Non-Intubated Patients with COVID-19 Acute Respiratory Failure: Guidance from an International Group of Healthcare Workers

Non-intubated patients with acute respiratory failure due to COVID-19 could benefit from awake proning. Awake proning is an attractive intervention in settings with limited resources, as it comes with no additional costs. However, awake proning remains poorly used probably because of unfamiliarity and uncertainties regarding potential benefits and practical application. To summarize evidence for benefit and to develop a set of pragmatic recommendations for awake proning in patients with COVID-19 pneumonia, focusing on settings where resources are limited, international healthcare professionals from high and low- and middle-income countries (LMICs) with known expertise in awake proning were invited to contribute expert advice. A growing number of observational studies describe the effects of awake proning in patients with COVID-19 pneumonia in whom hypoxemia is refractory to simple measures of supplementary oxygen. Awake proning improves oxygenation in most patients, usually within minutes, and reduces dyspnea and work of breathing. The effects are maintained for up to 1 hour after turning back to supine, and mostly disappear after 6-12 hours. In available studies, awake proning was not associated with a reduction in the rate of intubation for invasive ventilation. Awake proning comes with little complications if properly implemented and monitored. Pragmatic recommendations including indications and contraindications were formulated and adjusted for resource-limited settings. Awake proning, an adjunctive treatment for hypoxemia refractory to supplemental oxygen, seems safe in non-intubated patients with COVID-19 acute respiratory failure. We provide pragmatic recommendations including indications and contraindications for the use of awake proning in LMICs.

[Principles of intensive medical care in pregnant patients]

As the incidence of diseases during pregnancy or in the puerperium necessitating intensive medical care is very low, intensive care physicians are faced with a multitude of unfamiliar challenges in the treatment of this patient collective. The physiological and pathophysiological alterations during pregnancy induce some specific features with respect to the intensive medical treatment of pregnant or postpartum patients. Therefore, the first article in this CME series summarizes the most important principles and current recommendations on the care of pregnant or postpartum patients who need intensive medical treatment, always under consideration of the well-being of mother and child. The second article describes the diagnostics and treatment of special selected pathologies.

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.

Prone positioning and convalescent plasma therapy in a critically ill pregnant woman with COVID-19

Prone positioning is feasible in pregnancy and may have contributed to the positive outcome in this case. Doctors should not be reluctant to move a patient to a prone position just because they are pregnant.

Prone Positioning for Pregnant Women With Hypoxemia Due to Coronavirus Disease 2019 (COVID-19)

The coronavirus disease 2019 (COVID-19) pandemic has prompted expanded use of prone positioning for refractory hypoxemia. Clinical trials have demonstrated beneficial effects of early prone positioning for acute respiratory distress syndrome (ARDS), including decreased mortality. However, pregnant women were excluded from these trials. To address the need for low-cost, low-harm interventions in the face of a widespread viral syndrome wherein hypoxemia predominates, we developed an algorithm for prone positioning of both intubated and nonintubated pregnant women. This algorithm may be appropriate for a wide spectrum of hypoxemia severity among pregnant women. The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus is responsible for the clinical manifestations of COVID-19. This syndrome can manifest as severe pneumonia complicated by hypoxemia and ARDS. Given the current global COVID-19 pandemic, with a large number of ARDS cases, there is renewed interest in the use of prone positioning to improve oxygenation in moderate or severe hypoxemia. Among the populations who can benefit from prone positioning are pregnant women experiencing severe respiratory distress, as long as the physiologic changes and risks of pregnancy are taken into account.

Putting It All Together: Clinical Considerations in the Care of Critically Ill Obstetric Patients with COVID-19

Pregnant patients with severe acute respiratory syndrome coronavirus 2, the virus responsible for the clinical condition newly described in 2019 as coronavirus disease 2019 (COVID-19) and illness severity to warrant intensive care have a complex disease process that must involve multiple disciplines. Guidelines from various clinical societies, along with direction from local health authorities, must be considered when approaching the care of an obstetric patient with known or suspected COVID-19. With a rapidly changing landscape, a simplified and cohesive perspective using guidance from different clinical society recommendations regarding the critically-ill obstetric patient with COVID-19 is needed. In this article, we synthesize various high-level guidelines of clinical relevance in the management of pregnant patients with severe disease or critical illness due to COVID-19. KEY POINTS: · When caring for severely ill obstetric patients with COVID-19, one must be well versed in the complications that may need to be managed including, but not limited to adult respiratory distress syndrome with need for mechanical ventilation, approach to refractory hypoxemia, hemodynamic shock, and multiorgan system failure.. · Prone positioning can be done safely in gravid patients but requires key areas of support to avoid abdominal compression.. · For the critically ill obstetric patient with COVID-19, the focus should be on supportive care as a bridge to recovery rather than delivery as a solution to recovery..

Novel coronavirus-related acute respiratory distress syndrome in a patient with twin pregnancy: A case report

We present the case of a 39-year-old woman, G1P0, who had conceived twins via in-vitro fertilization, who presented at 27 weeks of gestation with nasal congestion and dry cough for 7 days. On presentation, her physical examination was benign, except for sinus tachycardia, and she was oxygenating adequately on room air. Laboratory studies were unremarkable, except a PCR test positive for SARS-COV2, and a CT scan of her chest showed bilateral multi-focal ground-glass opacities. A fetal non-stress test was reassuring. She was treated with intravenous fluids, ceftriaxone, azithromycin, and hydroxychloroquine. During her hospital stay, she developed progressively worsening respiratory failure, initially requiring non-invasive ventilation, and subsequently progressed to acute respiratory distress syndrome requiring mechanical ventilation. She then suffered from sudden hypoxemia and hemodynamic collapse, on maximal ventilatory support, prompting an emergency cesarean section at bedside. This led to rapid stabilization of hemodynamic parameters, and of her overall respiratory status. Both the twins were born prematurely, and one of them tested positive for SARS-COV2.

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Pregnant women are more susceptible to respiratory pathogens and might be at an increased risk for COVID-19.

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A case of acute respiratory distress syndrome due to SARS-CoV2 in a patient pregnant with twins is discussed.

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A dramatic improvement in oxygenation was observed after delivery.

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One of the twins tested positive for SARS-CoV2.

Respiratory Diseases of Pregnancy

Pregnant patients can suffer from the same respiratory diseases as the general population in addition to unique syndromes of pregnancy (such as pre-eclampsia and tocolytic induced pulmonary edema, and pregnancy induced cardiomyopathy). Pregnancy by itself may add certain challenges such as difficult intubation. The critically ill pregnant patient requires a multidisciplinary approach and early inclusion of obstetrical expertise is paramount in managing these patients especially in the third trimester.

Recent advances in the diagnosis and management of sepsis in pregnancy

Background: Maternal sepsis accounts for 11% of all maternal deaths worldwide. It is the third most common direct cause of maternal death and is a major contributor to other common causes of maternal death, such as haemorrhage and thromboembolism. Methods: This review addresses important topics, including the epidemiology, risk factors, prevention, diagnosis, care bundles and management of maternal sepsis, including antibiotic treatment, and critical care interventions such as extracorporeal membrane oxygenation. Preventative measures that have had an impact on maternal sepsis as well as future research directions are also covered in this review. Case studies of maternal sepsis which highlight key learning points relevant to all clinicians involved in the management of obstetric patients will also be presented. Results: Although, historically, maternal death from sepsis was considered to be a problem for low-income countries, severe obstetric morbidity and maternal death from sepsis are increasing in high-income countries. The global burden of maternal sepsis and the obstetric-related and patient-related risk factors and the likely sources are presented. Recent changes in definition and nomenclature are outlined, and challenges in diagnosis and identification are discussed. Conclusions: Following maternal sepsis, early diagnosis and early intervention are critical to save lives and prevent long-term adverse sequelae. Dogma surrounding critical care interventions in pregnancy is being challenged, and future research is warranted to maximise therapeutic options available for maternal septic shock.

The prone position in healthy pregnant women and in women with preeclampsia - a pilot study

BACKGROUND

The prone position is rarely used in medical settings in pregnancy. There is no published information about the prone position in women with preeclampsia. This study examined the feasibility and acceptability of the prone position in pregnant women, and the short-term effect of the prone position on blood pressure (BP) in term healthy pregnant women and in women with preeclampsia.

METHODS

After ethics approval, written consent and trial registration (ACTRN:12615000160538 registered 18/02/2015, date of first participant enrolled 03/03/2015), 50 healthy term pregnant women and 15 women with preeclampsia had BP, heart rate (HR), oxygen saturation (SpO2), respiratory rate (RR), fetal heart rate (FHR) and comfort levels measured in two positions: left lateral, and prone. Measurements were after five minutes rest in each position.

RESULTS

Mean ± SD age, gestation and body mass index for healthy pregnant women was 33 ± 4.1 years, 38 ± 1.0 weeks and 27 ± 3.2 kg.m^- 2 and for women with preeclampsia was 32 ± 4.7 years, 36 ± 3.4 weeks, 31 ± 5.6 kg.m^- 2 respectively. No clinically significant changes occurred in healthy pregnant women in the prone position. Systolic BP was reduced in the prone position in women with preeclampsia (P = 0.019, mean difference - 6.6 mmHg, 95% confidence interval - 11.9 to - 1.3 mmHg). 33% of women with preeclampsia experienced a 10 mmHg or greater reduction in systolic BP in the prone position. 42% of healthy pregnant women and 47% of women with preeclampsia preferred the prone position to lateral.

CONCLUSIONS

This is the first study to examine the prone position in women with preeclampsia. For short periods of time the prone position is feasible and comfortable in pregnant women including those at term. The prone position may reduce systolic BP in women with preeclampsia without obvious adverse effects. Larger studies with women lying for longer periods in the prone position are required. Pregnancy should not be a contraindication to the prone position for short periods of time.

TRIAL REGISTRATION

ACTRN:12615000160538.

Pregnancy complicated by influenza A ARDS requiring consecutive VV-ECMO treatment with successful vaginal delivery

A 29-year-old woman presented with influenza A ARDS at 23⁺⁰ weeks of gestation. Mechanical ventilation failed and VV-ECMO was started in a non-ECMO hospital. Transportation was performed on ECMO. Within 5 days ECMO weaning was successful. Fetal condition was stable, and decision to continue pregnancy was taken. However, second VV-ECMO was needed due to ventilator-associated pneumonia. At 25⁺⁶ weeks, the patient spontaneously delivered a neonate vaginally. Patient's condition improved, and ECMO could be removed 10 days postpartum. 2-year follow-up showed no severe consequences in the mother and the child.

Influence of the prone position on a stretcher for pregnant women on maternal and fetal hemodynamic parameters and comfort in pregnancy

OBJECTIVES:

To analyze the influence of lying in prone position on a specially designed stretcher on the maternal-fetal hemodynamic parameters and comfort of pregnant women.

METHODS:

A randomized, controlled trial with 33 pregnant women divided into 2 groups: pregnant group sequence 1 and pregnant group sequence 2. The order of positions used in sequence 1 was Fowler's position, prone position, supine position, left lateral, Fowler's position 2, supine position 2, prone position 2 and left lateral 2. The order of positions used in sequence 2 was Fowler's position, prone position, left lateral, supine position, Fowler's position 2, left lateral 2, prone position 2 and supine position 2. Each woman remained in each position for 6 minutes. For the statistical analyses, we used Wilcoxon's test for 2 paired samples when comparing the prone position with the other positions. The variables are presented in graphs showing the means and 95% confidence intervals. Trial Registration: Clinical Trial No. ISRCTN41359519.

RESULTS:

All the parameters were within the standards of normality. There were no differences between positions in terms of maternal heart rate, diastolic blood pressure, oxygen saturation and fetal heart rate. However, there were significant decreases in respiratory rate and systolic blood pressure in prone position 2 compared with left lateral 2. There was an increase in oxygen saturation in prone position compared with Fowler's position and supine position 2 in both sequences. All the women reported feeling comfortable in the prone position.

CONCLUSIONS:

The prone position was considered safe and comfortable and could be advantageous for improving oxygen saturation and reducing the systolic blood pressure and respiratory rate.

Treatment of ARDS With Prone Positioning

Prone positioning was first proposed in the 1970s as a method to improve gas exchange in ARDS. Subsequent observations of dramatic improvement in oxygenation with simple patient rotation motivated the next several decades of research. This work elucidated the physiological mechanisms underlying changes in gas exchange and respiratory mechanics with prone ventilation. However, translating physiological improvements into a clinical benefit has proved challenging; several contemporary trials showed no major clinical benefits with prone positioning. By optimizing patient selection and treatment protocols, the recent Proning Severe ARDS Patients (PROSEVA) trial demonstrated a significant mortality benefit with prone ventilation. This trial, and subsequent meta-analyses, support the role of prone positioning as an effective therapy to reduce mortality in severe ARDS, particularly when applied early with other lung-protective strategies. This review discusses the physiological principles, clinical evidence, and practical application of prone ventilation in ARDS.

Efficacy of prone position in acute respiratory distress syndrome patients: A pathophysiology-based review

Acute respiratory distress syndrome (ARDS) is a syndrome with heterogeneous underlying pathological processes. It represents a common clinical problem in intensive care unit patients and it is characterized by high mortality. The mainstay of treatment for ARDS is lung protective ventilation with low tidal volumes and positive end-expiratory pressure sufficient for alveolar recruitment. Prone positioning is a supplementary strategy available in managing patients with ARDS. It was first described 40 years ago and it proves to be in alignment with two major ARDS pathophysiological lung models; the "sponge lung" - and the "shape matching" -model. Current evidence strongly supports that prone positioning has beneficial effects on gas exchange, respiratory mechanics, lung protection and hemodynamics as it redistributes transpulmonary pressure, stress and strain throughout the lung and unloads the right ventricle. The factors that individually influence the time course of alveolar recruitment and the improvement in oxygenation during prone positioning have not been well characterized. Although patients' response to prone positioning is quite variable and hard to predict, large randomized trials and recent meta-analyses show that prone position in conjunction with a lung-protective strategy, when performed early and in sufficient duration, may improve survival in patients with ARDS. This pathophysiology-based review and recent clinical evidence strongly support the use of prone positioning in the early management of severe ARDS systematically and not as a rescue maneuver or a last-ditch effort.

Acute respiratory failure and mechanical ventilation in pregnant patient: A narrative review of literature

Physiological changes of pregnancy imposes higher risk of acute respiratory failure (ARF) with even a slight insult and remains an important cause of maternal and fetal morbidity and mortality. Although pregnant women have different respiratory physiology and different causes of ARF, guidelines specific to ventilatory settings, goals of oxygenation and weaning process could not be framed due to lack of large-scale randomized controlled trials. During the 2009 H1N1 pandemic, pregnant women had higher morbidity and mortality compared to nonpregnant women. During this period, alternative strategies of ventilation such as high-frequency oscillatory ventilation, inhalational of nitric oxide, prone positioning, and extra corporeal membrane oxygenation were increasingly used as a desperate measure to rescue pregnant patients with severe hypoxemia who were not improving with conventional mechanical ventilation. This article highlights the causes of ARF and recent advances in invasive, noninvasive and alternative strategies of ventilation used during pregnancy.

Critical care in pregnancy--is it different?

In the first part of this review, the epidemiology of obstetric critical care is discussed. This includes the incidence of severe morbidity in pregnancy, identification of critically ill and potentially critically ill patients, the incidence of obstetric ICU admissions, the type of critical illness by stage of pregnancy, ICU admission diagnoses, the severity of illness in obstetric ICU patients compared to non-obstetric patients, ICU mortality of obstetric patients, the ICU proportion of total maternal mortality, and the causes of death for obstetric patients in ICU. In the second part, the management of obstetric patients who happen to be admitted to a general ICU is discussed. Rather than focusing on the management of particular obstetric conditions, general principles of ICU management will be discussed as applied to obstetric ICU patients. These include drug safety, monitoring the fetus, management of the airway, sedation, muscle relaxation, ventilation, cardiovascular support, thromboprophylaxis, and radiology and ethical issues.