A modified Delphi approach to determine current treatment advances for the development of a resuscitation program for maternal cardiac arrest

OBJECTIVE

Maternal cardiac arrest is a rare and complex process requiring pregnancy-specific responses and techniques. The goals of this study were to (1) identify, evaluate, and determine the most current best practices to treat this patient population and (2) establish a standardized set of guidelines to serve as a foundation for a future educational simulation-based curriculum.

STUDY DESIGN

We used a three-step modified Delphi process to achieve consensus. Twenty-two healthcare experts from across North America agreed to participate in the expert panel. In round 1, 12 pregnancy-specific best practice statements were distributed to the expert panel. Panelists anonymously ranked these using a 7-point Likert scale and provided feedback. Round 2 consisted of a face-to-face consensus meeting where statements that had not already achieved consensus were discussed and then subsequently voted upon by the panelists.

RESULTS

Through two rounds, we achieved consensus on nine evidence-based pregnancy-specific techniques to optimize response to maternal cardiac arrest. Round one resulted in one of the 12 best practice statements achieving consensus. Round two resulted in six of the remaining 12 gaining consensus. Best practice techniques involved use of point-of care ultrasound, resuscitative cesarean delivery, cardiopulmonary resuscitation techniques, and the use of extracorporeal cardiopulmonary resuscitation.

CONCLUSION

The results of this study provide the foundation to develop an optimal, long-term strategy to treat cardiac arrest in pregnancy. We propose these nine priorities for standard practice, curricula, and guidelines to treat maternal cardiac arrest and hope they serve as a foundation for a future educational curriculum.

Management of high-risk pulmonary embolism in pregnancy

Pregnancy-associated high-risk pulmonary embolism (PE) is among the most frequent causes of maternal mortality in the Western world, by causing hemodynamic instability and circulatory failure through a large thrombotic pulmonary obstruction. The very challenging management of these dramatic situations comprises the need to quickly select a therapy of pulmonary reperfusion or hemodynamic replacement, while taking into account both maternal and fetal risks. In this review, we discuss the role of risk stratification in pregnancy-associated PE and the available evidence to support the use of thrombolysis, catheter-directed thrombectomy/thrombolysis, surgical embolectomy and extracorporeal membrane oxygenation. Despite the lack of comparative studies and solid evidence, most reported cases of high-risk pregnancy-associated PE have been treated with thrombolysis, with high maternal and fetal survivals, and thrombolysis is suggested by guidelines in life-threatening PE. For women in the peripartum and early post-partum period, non-fibrinolytic treatments may be preferred as a first-line treatment, if available, because of the particularly high bleeding risk. In all cases, pregnancy-associated high-risk PE requires a multidisciplinary approach involving PE response teams and obstetricians.

Venoarterial Extracorporeal Membrane Oxygenation in Massive Pulmonary Embolism-Related Cardiac Arrest: A Systematic Review

OBJECTIVE

Management of patients experiencing massive pulmonary embolism-related cardiac arrest is controversial. Venoarterial extracorporeal membranous oxygenation has emerged as a potential therapeutic option for these patients. We performed a systematic review assessing survival and predictors of mortality in patients with massive PE-related cardiac arrest with venoarterial extracorporeal membranous oxygenation use.

DATA SOURCES

A literature search was started on February 16, 2020, and completed on March 16, 2020, using PubMed, Embase, Cochrane Central, Cinahl, and Web of Science.

STUDY SELECTION

We included all available literature that reported survival to discharge in patients managed with venoarterial extracorporeal membranous oxygenation for massive PE-related cardiac arrest.

DATA EXTRACTION

We extracted patient characteristics, treatment details, and outcomes.

DATA SYNTHESIS

About 301 patients were included in our systemic review from 77 selected articles (total screened, n = 1,115). About 183 out of 301 patients (61%) survived to discharge. Patients (n = 51) who received systemic thrombolysis prior to cannulation had similar survival compared with patients who did not (67% vs 61%, respectively; p = 0.48). There was no significant difference in risk of death if PE was the primary reason for admission or not (odds ratio, 1.62; p = 0.35) and if extracorporeal membranous oxygenation cannulation occurred in the emergency department versus other hospital locations (odds ratio, 2.52; p = 0.16). About 53 of 60 patients (88%) were neurologically intact at discharge or follow-up. Multivariate analysis demonstrated three-fold increase in the risk of death for patients greater than 65 years old (adjusted odds ratio, 3.08; p = 0.03) and six-fold increase if cannulation occurred during cardiopulmonary resuscitation (adjusted odds ratio, 5.67; p = 0.03).

CONCLUSIONS

Venoarterial extracorporeal membranous oxygenation has an emerging role in the management of massive PE-related cardiac arrest with 61% survival. Systemic thrombolysis preceding venoarterial extracorporeal membranous oxygenation did not confer a statistically significant increase in risk of death, yet age greater than 65 and cannulation during cardiopulmonary resuscitation were associated with a three- and six-fold risks of death, respectively.

Extracorporeal membrane oxygenation in pregnant and postpartum patients: a systematic review

PURPOSE

Information on the use of extracorporeal membrane oxygenation (ECMO) in obstetric patients is scarce. The objective was to conduct a systematic review examining ECMO use in pregnant and postpartum patients in order to identify indications leading to ECMO use and to assess mortality rates.

MATERIALS AND METHODS

PubMed, EMBASE, Cochrane Library, and SCOPUS were searched using the terms "extracorporeal membrane oxygenation" and "pregnancy" up to 1 November 2020. Case reports and case series reporting the use of ECMO in pregnancy were eligible. Data about maternal age, gestational age, diagnosis, type of ECMO, time on ECMO, pregnancy outcomes, and maternal survival were extracted from studies.

RESULTS

The search yielded 1696 citations, of which 125 were included. There were 213 obstetric patients treated with ECMO over a 30-year period. The frequency of reports increased considerably over the last decade. The majority of patients were treated in their third trimester (28.2%) or postpartum (32.9%). Most common etiologies included influenza-induced ARDS (27.7%), pulmonary embolism (13.6%), peripartum cardiomyopathy (11.7%), and infection (11.7%). Pregnancy outcomes ended with live births, either on ECMO (15.5%, 95% CI 10.6-20.4) or not on ECMO (58.3%, 95% CI 51.7-64.9), in fetal demise (8.9%, 95% CI 5.1-12.7), or in spontaneous or induced abortion on ECMO (4.2%, 95% CI 1.5-6.9) or not on ECMO (4.2%, 95% CI 1.5-6.9). Maternal survival was 79.3%.

CONCLUSION

Although women placed on ECMO had a high mortality rate, this is likely an indication of the severity of illness. Overall, ECMO appears to be a valid therapy for the temporary support of vital organs in severely ill pregnant women.

Extracorporeal Life Support in Pregnancy: A Systematic Review

Background The use of extracorporeal life support (ECLS) has expanded to include unique populations such as peripartum women. This systematic review aims to (1) quantify the number of cases and indications for ECLS in women during the peripartum period reported in the literature and (2) report maternal and fetal complications and outcomes associated with peripartum ECLS. Methods and Results This review was registered in PROSPERO (CRD42018108142). MEDLINE, Embase, and CINAHL were searched for case reports, case series, and studies reporting cases of ECLS during the peripartum period that reported one or more of the following outcomes: maternal survival, maternal complications, fetal survival, and/or fetal complications. Qualitative assessment of 221 publications evaluated the number of cases, clinical details, and maternal and fetal outcomes of ECLS during the peripartum period. There were 358 women included and 68 reported fetal outcomes in cases where the mother was pregnant at the time of cannulation. The aggregate maternal survival at 30 days was 270 (75.4%) and at 1 year was 266 (74.3%); fetal survival was 44 (64.7%). The most common indications for ECLS overall in pregnancy included acute respiratory distress syndrome 177 (49.4%), cardiac failure 67 (18.7%), and cardiac arrest 57 (15.9%). The most common maternal complications included mild to moderate bleeding 66 (18.4%), severe bleeding requiring surgical intervention 48 (13.4%), and intracranial neurologic morbidity 19 (5.3%). The most commonly reported fetal complications included preterm delivery 33 (48.5%) and neonatal intensive care unit admission 19 (27.9%). Conclusions Reported rates of survival in ECLS in pregnant and postpartum women are high and major complications relatively low.

Extracorporeal Life Support as Salvage Therapy for Massive Pulmonary Embolus and Cardiac Arrest in Pregnancy

BACKGROUND

Massive pulmonary embolus (PE) with prolonged cardiac arrest in the setting of pregnancy has few treatment options. Selections are further restricted if there are contraindications to the standard therapies of embolectomy and thrombolysis. We report a case of extracorporeal life support (ECLS) used as salvage therapy for a critically ill pregnant patient.

CASE REPORT

A 21-year-old woman presented to a small rural hospital with chest pain, dyspnea, hypoxia, and syncope. In their emergency department, she suffered 2 episodes of cardiac arrest requiring cardiopulmonary resuscitation, and fetal demise followed. A computed tomography scan revealed a saddle PE. She was transferred to our tertiary care hospital and arrived critically ill, on multiple vasopressors, and in cardiogenic shock. Because standard treatments, namely thrombolysis and embolectomy, were contraindicated in this case, ECLS was employed for 7 days. She was discharged home after 23 days, and at follow-up 5 months after her admission, she was found to have made a near-complete recovery. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: ECLS is a viable option as salvage therapy for pregnant patients with massive PE who have contraindications to thrombolysis and embolectomy.

Emergent transesophageal echocardiography in hemodynamically unstable obstetric patients

BACKGROUND

The obstetric population has an increasing incidence of comorbid conditions. These, coupled with the possibility of acute embolic events involving air, amniotic fluid, and thrombus, increase the likelihood of hemodynamic instability. Although the utility of transesophageal echocardiography to guide management in cardiac and high-risk, non-cardiac surgical populations has been well established, the emergent use in critically-ill parturients has not been comprehensively evaluated.

METHODS

Using our departmental transesophageal echocardiography database of 28 293 examinations, parturients were identified who underwent emergent transesophageal echocardiography for evaluation of hemodynamic instability, including cardiac arrest, between January 1999 and March 2014. Transesophageal echocardiography findings and their impact on patient management were analyzed.

RESULTS

Ten peripartum patients were evaluated. Six patients became unstable during dilation and evacuation procedures; one after a forceps delivery; one during and one after cesarean delivery; and one during a postpartum laparotomy. Six patients proceeded to cardiac arrest; however, all women survived their initial operation and resuscitation. Transesophageal echocardiography was instrumental in determining the etiology and guiding resuscitation in all 10 patients including emergent cardiac surgical intervention with cardiopulmonary bypass (n=2). Seven patients survived to hospital discharge, but three died after experiencing neurologic complications.

CONCLUSIONS

Severe hemodynamic instability and cardiac arrest can occur in previously healthy parturients in pregnancy. Our data suggest that emergent transesophageal echocardiography is a valuable tool in determining the etiology and directing therapy of refractory hypotension or cardiac arrest in obstetric patients.

Pulmonary embolus in pregnancy

Venous thromboembolism remains in the top three leading causes of maternal death in the US, representing 10.2% of pregnancy-related deaths. Risk of developing a pulmonary embolus appears to increase throughout pregnancy, with a peak in incidence in the early postpartum period. Overall the incidence of VTE is 0.6-1.8 VTEs per 1000 deliveries. Diagnosis and management of pulmonary embolus can prove challenging, but the aim should be to optimize maternal outcome while minimizing hemorrhagic complications. Low-molecular-weight heparin is a safe and effective treatment for the majority of cases of pregnancy-related pulmonary embolus.

Emergent limited perioperative transesophageal echocardiography: should new guidelines exist for limited echocardiography training for anesthesiologists?

Bedside limited echocardiography, or focused cardiac ultrasound, continues to gain popularity in many emergency rooms, intensive care units, and operating rooms as a rapid method of assessing unstable patients. Effective monitoring of cardiovascular function in conditions like cardiac arrest or near-arrest is the crucial step to guide successful resuscitative efforts. Transesophageal echocardiography (TEE) has emerged as one of the preferred cardiac diagnostic and monitoring modalities in the intraoperative setting due to the fact that it is less invasive than many other monitors, is immediately accessible, and allows for continuous real-time monitoring of cardiac function. However, the minimum training requirements needed for the anesthesia provider to obtain the competency, knowledge, and skills for basic certification in perioperative TEE far exceed those developed for other medical specialties. We believe there is an urgent need to develop (1) practical guidelines for emergent perioperative TEE use for anesthesiologists and (2) a requisite educational curriculum to teach the basic skills necessary to aid in the diagnosis and treatment of cardiac arrest or near-arrest scenarios. The measures elucidated in this report summarize the efforts of the Department of Anesthesiology at the University of Florida in establishing the necessary steps to make this process not only practical, but accessible to all trainees.We hope that these collective efforts will provide more trainees the confidence in utilizing TEE to aid in establishing a diagnosis in critical situations.

Can transthoracic echocardiography be used to predict fluid responsiveness in the critically ill patient? A systematic review

Introduction. We systematically evaluated the use of transthoracic echocardiography in the assessment of dynamic markers of preload to predict fluid responsiveness in the critically ill adult patient. Methods. Studies in the critically ill using transthoracic echocardiography (TTE) to predict a response in stroke volume or cardiac output to a fluid load were selected. Selection was limited to English language and adult patients. Studies on patients with an open thorax or abdomen were excluded. Results. The predictive power of diagnostic accuracy of inferior vena cava diameter and transaortic Doppler signal changes with the respiratory cycle or passive leg raising in mechanically ventilated patients was strong throughout the articles reviewed. Limitations of the technique relate to patient tolerance of the procedure, adequacy of acoustic windows, and operator skill. Conclusions. Transthoracic echocardiographic techniques accurately predict fluid responsiveness in critically ill patients. Discriminative power is not affected by the technique selected.

Three-dimensional transesophageal echocardiography: diagnosing intraoperative pulmonary artery thrombus

A 61-year-old patient with the diagnosis of acute heart failure based on severe mitral valve insufficiency due to chordae rupture was scheduled for surgery. Intraoperatively, a standard two-dimensional transesophageal echocardiogram (2D-TEE) examination, revealed severe mitral valve regurgitation due to a prolaps with chordal rupture and an echo dense structure in the pulmonary artery (PA). Because it was not possible to visualize this echo dense structure fully with 2D-TEE we performed a three-dimensional transesophageal echocardiogram (3D-TEE). On the basis of the clear demonstration on 3D-TEE of an at least 6-cm thrombus in the PA we decided to remove the thrombus prior to proceeding with the mitral valve repair. We conclude that 3D-TEE can alter surgical management and provide more valuable information on PA thrombus than that obtained by 2D-TEE.