Cardiac Arrest during Transesophageal Echocardiogram (TEE) due to Acute Right Ventricular Failure

The case of a patient who suffered cardiac arrest while undergoing transesophageal echocardiography (TEE) is presented here. A 75-year-old man with moderate right ventricular (RV) dysfunction and pulmonary hypertension became bradycardic and hypotensive after receiving propofol for procedural sedation. His profound hypotension ultimately led to a pulseless electrical activity (PEA) cardiac arrest. TEE images captured immediately prior to cardiac arrest show a severely dilated and hypokinetic RV, consistent with acute right ventricular failure. This case highlights the potentially fatal consequences of procedural sedation in patients with RV dysfunction and pulmonary hypertension.

Temporal Trends in Characteristics and Outcomes Associated With In‐Hospital Cardiac Arrest: A 20‐Year Analysis (1999–2018)

Background Despite advances in resuscitation medicine, the burden of in‐hospital cardiac arrest (IHCA) remains substantial. The impact of these advances and changes in resuscitation guidelines on IHCA survival remains poorly defined. To better characterize evolving patient characteristics and temporal trends in the nature and outcomes of IHCA, we undertook a 20‐year analysis of a national database. Methods and Results We analyzed the National Inpatient Sample (1999–2018) using International Classification of Diseases , Ninth Revision and Tenth Revision, Clinical Modification ( ICD‐9‐CM and ICD‐10‐CM ) codes to identify all adult patients suffering IHCA. Subgroup analysis was performed based on the type of cardiac arrest (ie, ventricular tachycardia/ventricular fibrillation or pulseless electrical activity‐asystole). An age‐ and sex‐adjusted model and a multivariable risk‐adjusted model were used to adjust for potential confounders. Over the 20‐year study period, a steady increase in rates of IHCA was observed, predominantly driven by pulseless electrical activity‐asystole arrest. Overall, survival rates increased by over 10% after adjusting for risk factors. In recent years (2014–2018), a similar trend toward improved survival is noted, though this only achieved statistical significance in the pulseless electrical activity‐asystole cohort. Conclusions Though the ideal quality metric in IHCA is meaningful neurological recovery, survival is the first step toward this. As overall IHCA rates rise, overall survival rates are improving in tandem. However, in more recent years, these improvements have plateaued, especially in the realm of ventricular tachycardia/ventricular fibrillation‐related survival. Future work is needed to better identify characteristics of IHCA nonsurvivors to improve resource allocation and health care policy in this area.

Life-Threatening Cardiac Arrhythmias during Anesthesia and Surgery

Life-threatening arrhythmias are frequently encountered during anesthesia for cardiac or non-cardiac surgery. They result in a significant cause of morbidity and mortality, particularly in elderly patients. Predisposing factors like electrolytes abnormalities, pre-existing cardiac disease, intubation procedure, anesthetic medications, and various surgical stimulation need to be determined. Early diagnosis and commencement of an appropriate treatment protocol may be lifesaving. Treatment usually involves correction of the underlying causes, cardiac electroversion, and the use of one or more antiarrhythmic agents. Although ventricular tachycardia, ventricular fibrillation, torsade de pointes, and pulseless electrical activity are considered malignant arrhythmias that can lead to cardiac arrest, other types of Brady and tachyarrhythmias are also included in this chapter to enable adopting a more objective approach in the management of arrhythmias intraoperatively, avoiding risks of inappropriate management strategies.

Abstract 13292: Comparison of Outcomes Between Pulseless Electrical Activity by Electrocardiography and Pulseless Myocardial Activity by Echocardiography in Out-of-Hospital Cardiac Arrest

Objective: To measure prevalence of discordance between electrical activity recorded by electrocardiography (ECG) and myocardial activity visualized by echocardiography (echo) in patients presenting after cardiac arrest and to compare survival outcomes in cohorts defined by ECG and echo. Methods: This is a secondary analysis of a previously published prospective study at twenty hospitals. Patients presenting after out-of-hospital arrest were included. The cardiac electrical activity was defined by ECG and contemporaneous myocardial activity was defined by bedside echo. Myocardial activity by echo was classified as myocardial asystole- -the absence of myocardial movement, pulseless myocardial activity (PMA)--visible myocardial movement but no pulse, and myocardial fibrillation- -visualized fibrillation. Primary outcome was the prevalence of discordance between electrical activity and myocardial activity. Secondary outcome was survival to hospital discharge. Results: 793 patients and 1943 pauses in CPR were included. 28.6% of CPR pauses demonstrated a difference in electrical activity (ECG) and myocardial activity (echo), 5.0% with asystole (ECG) and PMA (echo), and 22.1% with PEA (ECG) and myocardial asystole (echo). Survival to hospital admission for patients with PMA (echo) was 29.1% (95%CI-23.9-34.9) compared to those with PEA (ECG) (21.4%, 95%CI-17.7-25.6). Twenty-five percent of the 32 pauses in CPR with a shockable rhythm by echo demonstrated a non-shockable rhythm by ECG and were not defibrillated. One of these patients survived, a patient with asystole on ECG and vfib by echo survived because vfib was identified on ECG during a subsequent pause and was defibrillated. Conclusion: Patients in cardiac arrest commonly demonstrate different electrical (ECG) and myocardial activity (echo). Further research is needed to better define cardiac activity during cardiac arrest and to explore outcome between groups defined by electrical and myocardial activity.

Abstract 12356: Prevalence and Patterns of Injury Detected by Head-to-Pelvis Sudden Death Computed Tomography Following Cardiopulmonary Resuscitation

Introduction: Patients resuscitated from out-of-hospital cardiac arrest (OHCA) frequently have skeletal and visceral injuries identifiable by computed tomography, although the prevalence, types of injury, and potential effects on clinical outcomes are poorly characterized. Methods: We assessed the prevalence of resuscitation-attributable injury in a prospective, observational diagnostic utility study of a head-to-pelvis sudden death computed tomography (SDCT) protocol after successful resuscitation from OHCA. SDCT was performed within six hours of arrival at two academic medical centers. CT data were independently analyzed by two blinded radiologists. Primary outcomes included total injuries and time-critical injuries (such as organ laceration). Exploratory outcomes were clinical associations with injury and survival to discharge. Results: Among 104 patients with OHCA (mean age 56 ± 15 years, 31% female), 59% of events were witnessed and 60% had bystander CPR. Initial rhythms were pulseless electrical activity (38%), ventricular tachycardia/fibrillation (29%), and asystole/unknown (33%). Mean CPR time was 15.4 ± 10.6 minutes; mechanical chest compression systems were used in 27% of cases. The prevalence of injury was high (80%; Table), including 19 patients (18%) with time-critical findings. Compared to patients without injury, patients with injury had numerically lower BMI (24.2 ± 7.7 vs. 26.7 ± 8.0), higher use of mechanical CPR (29% vs. 19%), longer CPR time (16.1 ± 11.0 vs. 12.3 ± 8.5 min), and lower survival to discharge (40% vs. 52%), although none were significant (p= NS for all). Conclusion: In patients resuscitated from OHCA, head-to-pelvis SDCT identified injury in most patients, with nearly one in five with time-critical findings and nearly one half with extensive ribcage injuries that may affect ventilation. These data suggest that SDCT has additional diagnostic utility and treatment implications beyond evaluating causes of OHCA.

Abstract 10125: Continuous Heart Rate Dynamics Preceding In-Hospital Cardiac Arrest of Respiratory Etiology

Introduction: Respiratory failure is a common cause of pulseless electrical activity (PEA) arrest in hospitalized patients, but how pathophysiologic changes in these conditions affect heart rate (HR) pre-arrest is not well described. We describe HR dynamics prior to in-hospital cardiac arrest (IHCA) among PEA/asystole arrest patients with respiratory etiology. Methods: In this retrospective descriptive study, we evaluated 67 patients with ≥3 hours of continuous ECG data recorded immediately preceding PEA/asystole IHCA in a single institution from 2010-2014. We identified respiratory arrest cases (eg. pneumonia, aspiration, pulmonary embolism, acute respiratory distress syndrome) by chart review and evaluated ECG patterns up to 24 hours prior to arrest to identify patterns of HR increase, HR decrease, sinus arrest, and escape rhythms. Results: We identified 31/67 patients with respiratory etiology (age 59±17 years, 52% male, 83% return of spontaneous circulation, 41% survived to discharge); of these 23/31(74%) fit an a priori model of HR response (Figure). Twelve cases demonstrated clear onset of HR increase at a median of 44 (IQR 28-507) minutes prior to arrest, while the remaining 11 cases started the monitoring period in sinus tachycardia. The mean peak HR was 120±20 bpm. An abrupt onset of HR decrease occurred at a median of 3.4 (IQR 2.3-5.9) minutes prior to arrest. Sinus arrest occurred during the HR decrease phase in 18/23 cases; the first escape rhythm was atrial in 11 (61%), junctional in 2 (11%) and ventricular in 3 (17%) cases. Conclusion: The majority of IHCA due to respiratory etiology (74%) follow a typical model of HR increase due to physiologic compensation to hypoxia, followed by rapid HR decrease leading to PEA arrest, likely from the vagal effect of hypoxia and sinus node suppression from acidosis. Understanding HR trends can aid clinical management as well as development of artificial intelligence models for prediction of IHCA.

Abstract 13102: Outcomes of Primary and Secondary Pulseless Electrical Activity During In-Hospital Cardiac Arrest

Background: Pulseless Electrical Activity (PEA) is common during in-hospital cardiac arrest. We investigated the development of four types of PEA: PEA as presenting clinical state (primary) and PEA secondary to transient return of spontaneous circulation (ROSC), ventricular fibrillation/tachycardia (VF/VT), or asystole (ASY). Methods: We analyzed 660 episodes of cardiac arrest at one Norwegian and three U.S. hospitals. ECG, chest compressions and ventilations were recorded by defibrillators during CPR. Clinical states were annotated using a graphical application. We quantified the transition intensities from PEA to ROSC (i.e. the immediate probability of a transition), and the observed half-lives for the four types of PEA (i.e. how quickly PEA develops into another clinical state), using Aalen’s additive model for time-to-event data. Results: The transition intensities to ROSC from primary PEA (n=386) and secondary PEA after ASY (n=226) were about 0.08 per minute, peaking at 6 and 9 min, respectively (figure, left). Thus, an average patient in these types of PEA has about 8% chance to achieve ROSC in one minute. Much higher transition intensities to ROSC of about 0.20 per min were observed for secondary PEA after transient ROSC (n=209) or VF/VT (n=225), peaking at 10 and 5 min, respectively. Half-live times for the four types of PEA (figure, right) were 8.5 min, 6.8 min, 4.6 min and 1.6 min, for primary PEA, and secondary PEA after ASY, transient ROSC and VF/VT, respectively. Discussion: The observed clinical development of PEA in terms of intensity, peak intensity and half-lives during resuscitation differs substantially between the four types of PEA. The chance of obtaining ROSC is considerably lower in primary PEA or PEA after ASY, compared to PEA following transient ROSC or after VF/VT. This may increase understanding of the nature of PEA and the process leading to ROSC; and allow for simple prognostic assessments during a resuscitation attempt.

October 2021 Critical Care Case of the Month: Unexpected Post-Operative Shock

No abstract available. Article truncated after 150 words. History of Present Illness: A 55-year-old man with a past medical history significant for endocarditis secondary to intravenous drug use, osteomyelitis of the right lower extremity was admitted for ankle debridement. Pre-operative assessment revealed no acute illness complaints and no significant findings on physical examination except for the ongoing right lower extremity wound. He did well during the approximate one-hour “incision and drainage of the right lower extremity wound”, but became severely hypotensive just after the removal of the tourniquet placed on his right lower extremity. Soon thereafter he experienced pulseless electrical activity (PEA) cardiac arrest and was intubated with return of spontaneous circulation being achieved rapidly after the addition of vasopressors. He remained intubated and on pressors when transferred to the intensive care unit for further management. PMH, PSH, SH, and FH: • S/P Right lower extremity incision and drainage for suspected osteomyelitis as above • Distant history of endocarditis related …