Transcutaneous Pacing Research Articles

The mechanism of transcutaneous gastric pacing treatment on gastrointestinal motility recovery and inflammation improvement in early-stage acute pancreatitis patients.

Acute pancreatitis (AP) is often accompanied by gastrointestinal motility disorders. The purpose of this study was to investigate the efficacy and possible mechanism of transcutaneous gastric pacing (TGP) in early-stage AP patients. Sixty-five AP patients were randomly divided into conventional treatment group and TGP group. The serum ghrelin and vasoactive intestinal peptide (VIP) were used to assess the possible gastrointestinal hormonal mechanism involved. The parameters of electrogastrogram (EGG) were used to evaluate the gastric motility in AP patients. The first defecation time was used to assess the recovery of intestinal motility. The heart rate variability (HRV) test was performed to assess autonomic nervous function. Compared with the conventional treatment group, the TGP treatment significantly improved symptoms in early AP patients, and shortened the first defecation time (p < 0.05) and the hospital days (p < 0.05). The level of VIP (P < 0.05) was also decreased in TGP group. The percentage of normal gastric slow waves (GSWS) (p < 0.05) was increased. The interleukin (IL)-6 level was decreased (P < 0.05). Concurrently, the vagal activity (HF) was increased (p < 0.01), the sympathetic activity (LF) was decreased (p < 0.01), and the ratio of sympathetic vagal (LF/HF) was decreased (p < 0.01). The TGP treatment significantly improves the clinical symptoms in early AP patients. It also increases the percentage of normal GSWS. The therapeutic effect of TGP may be caused by autonomic nervous function mechanisms.

A Change of Pace: Modifying Pacemaker Settings in the Emergency Department as Emergency Medicine Physicians, A Case Report

Background: Pacemakers are implantable or external devices that send electrical impulses allowing the heart to contract. Some common indications for permanent pacemaker placement include symptomatic bradycardia due to high grade atrioventricular (AV) block, sick sinus syndrome, chronic bifascicular block, and post-cardiac transplantation. Like all devices pacemakers can malfunction or stop working entirely. We present a patient with an implantable pacemaker/cardioverter and defibrillator (ICD) displaying symptomatic failure to capture and settings were adjusted in the emergency department. Adjustment in the emergency department (ED) resolved the patient's symptoms and required no further interventions.Case Report: An 82-year-old female with atrial fibrillation, heart failure, and a Medtronic dual chamber pacer/ICD presented to the emergency department for complaints of weakness and lightheadedness. Emergency medical services (EMS) noted intermittent bradycardia, hypotension, and decreased responsiveness. Electrocardiogram (ECG) revealed failure to capture. The Medtronic application was used to interrogate and reprogram the device. The settings were DDD at a rate of 60 beats per minute (BPM) with ventricular output of 4.5 millivolts (mV) and atrial output of 4.5 mV which were changed ventricular lead outputs from 4.5 mV to 8.0 mV and rate from 60 to 80 for additional cardiac output. After this adjustment, the bradycardia resolved, and ECG showed a successful AV-paced rhythm. Transcutaneous pacing was never required.Why should an emergency physician be aware of this?Adjustment of pacer settings in the ED in order to stabilize the critically ill patient is within the scope of the emergency physician. We can reduce stress to the patient and prevent hospitalizations. Pacemakers can become a tool to optimize treatment plans for an aging population where pacemakers are becoming more common.

Prehospital transcutaneous cardiac pacing in the United States: treatment epidemiology, predictors of treatment failure, and associated outcomes

ABSTRACT OBJECTIVES Transcutaneous cardiac pacing (TCP) is a potentially lifesaving therapy for patients who present in the prehospital setting with bradycardia that is causing hemodynamic compromise. Our objective was to examine the outcomes of patients who received prehospital TCP and identify predictors of TCP failure. METHODS We utilized the 2018-2021 ESO Data Collaborative public use research datasets for this study. All patients without a documented TCP attempt were excluded. Mortality was derived from hospital disposition data. TCP failure was defined as initiation of CPR following the first TCP attempt among patients who did not receive CPR prior to the first TCP attempt. Multivariable logistic regression models using age and sex as covariables were used to explore the association between prehospital vital signs and TCP failure. RESULTS During the study period, 13,270 patients received transcutaneous pacing and 2,560 of these patients had outcome data available. Overall, the mortality rate following TCP was 63.4%. Among patients who did not receive CPR prior to the first TCP attempt (n = 7,930), TCP failure (progression to cardiac arrest) occurred 20.4% of the time. Factors associated with TCP failure included increased body weight (>100 vs. 60-100 kg, aOR: 1.33 (1.15, 1.55)), a pre-pacing non-bradycardic heart rate (>50 vs. <40 bpm, aOR: 2.87 (2.39, 3.44)), and pre-TCP hypoxia (<80% vs. >90% SpO2, aOR: 6.01 (4.96, 7.29)). CONCLUSIONS Patients who undergo prehospital TCP are at high risk of mortality. Progression to cardiac arrest is common and associated with factors including increased weight, a non-bradycardic initial heart rate and pre-TCP hypoxia.

Bradycardic peri-arrest after electrical cardioversion for atrial fibrillation: a case report

Electrical cardioversion can precipitate prolonged bradycardia and cardiac arrest when the sinoatrial node is dysfunctional, and the escape rhythms from the atrioventricular node and ventricles fail to take over. We report the case of an elderly male who rapidly progressed into bradycardic peri-arrest after electrical cardioversion for persistent atrial fibrillation. Despite the immediate initiation of intravenous atropine and transcutaneous pacing, 2 minutes of cardiopulmonary resuscitation with further boluses of atropine and adrenaline were required before the return of spontaneous circulation. The patient was transferred to the intensive care unit, and a permanent pacemaker was implanted before discharge. Advanced age, long duration of atrial fibrillation, previous aortic valve replacement, use of anti-arrhythmic drugs, and intravenous propofol bolus were all contributing factors to this event. We summarise the relevant clinical features, risk factors, and management considerations, in the hope of promoting awareness of this rare complication of a common procedure.

PERCUTANEOUS MITRAL PLICATION FOR WEANING BY VA–ECMO IN PATIENT WITH OBSTRUCTIVE SAM ASSOCIATED WITH PRECLINICAL PHENOTYPE OF HYPERTROPHIC CARDIOMYOPATHY AND STEMI COMPLICATED BY CARDIOGENIC SHOCK

Abstract A 53–year–old man with a history of hypertrophic obstructive cardiomyopathy with a preclinical phenotype, classified at low risk of sudden cardiac death (HCM–SCD risk score 2.98%), and cardiac arrest (OHCA) in the absence of a shockable rhythm. The patient underwent cardiopulmonary resuscitation for more than 30 minutes before the diagnosis of complete atrioventricular block, masked by concomitant atrial stand–still, resolved after transcutaneous pacing. After temporary trans–venous cardiac pacing was obtained, the electrocardiogram revealed signs of an extensive anterolateral occlusive infarction (OMI), treated with primary angioplasty during percutaneous ventricular support (Impella CP). The ICU course was characterized by several ineffective attempts to wean from mechanical assistance to the circulation finally made possible by correction of outflow obstruction from mitral SAM, achieved by percutaneous mitral plication with MitraClip system. This case, in addition to suggesting an alternative strategy of weaning from mechanical assistance to the circulation in patients with a similar hemodynamic profile (SCAI D stage cardiogenic shock by dual mechanism: pump dysfunction and outflow obstruction), offers important insights into the management of OCHA in the absence of a shockable rhythm.

Cardiac Arrest During a Ferric Derisomaltose Infusion Followed by Complete Heart Block: A Case Report.

Ferric derisomaltose is the newest available parenteral iron formulation. Studies have demonstrated a good safety profile with improved tolerability compared to alternative parenteral iron formulations. To date there have been no reported acute, life-threatening cardiac events associated with ferric derisomaltose. An 86-year-old male who had previously tolerated routine iron infusions received a first dose of ferric derisomaltose at an outpatient infusion clinic. Six minutes into the infusion the patient became unresponsive with no palpable pulse. Return of spontaneous circulation was achieved after two minutes of chest compressions. Electrocardiogram showed complete heart block requiring transcutaneous pacing and vasopressor administration. The patient was transferred to the emergency department for stabilization and then admitted to the cardiac intensive care unit. During admission, the patient received a dual-chamber, permanent pacemaker without complication and was ultimately discharged. It may be reasonable to consider parenteral iron as a toxicological etiology for patients presenting with complete heart block temporally associated with parenteral iron administration, particularly in patients with underlying conduction abnormalities.

False Electrical Capture in Prehospital Transcutaneous Pacing by Paramedics: A Case Series

Introduction The use of transcutaneous pacing (TCP) for unstable bradycardia has a class 2B recommendation from the American Heart Association. Prior studies have not adequately described the frequency or possible causes of treatment failure. EMS clinicians and leaders have reported false electrical capture as a potential cause. In this study, we aimed to describe the frequency of true electrical capture, documented verification of mechanical capture, and its association with systolic blood pressure (SBP) and survival. Methods This was a retrospective study of patients treated by an urban, hospital-based EMS network comprising two EMS agencies between March 2021 and March 2023. Inclusion criteria were adults with a heart rate of <60 bpm and attempted TCP. Variables included: initial electrocardiogram rhythm, SBP, current applied, neurological status at discharge, and diagnosis. The primary outcome was true electrical capture, defined as the presence of a visible wide QRS and T wave. This enabled calculation of false electrical capture. Additional outcomes included change in SBP and neurological status at discharge. Results 19 of the 23 (82.6%) patients who underwent TCP had false electrical capture despite all 23 having documented mechanical capture by palpated pulse. For patients with true electrical capture, the median change in SBP was +40 mmHg (IQR = 24.25, range= −12 to +49 mmHg). For patients with false electrical capture, the median change in SBP was −1 mmHg (IQR = 58.50, range= −90 to +23 mmHg). Median current for patients with true electrical capture was 95 mA (IQR = 13.75, range = 85–110) versus 70 mA (IQR = 30, range = 55–160) in those with false electrical capture. 16 (69.6%) had outcome data available. Patients with true electrical capture and outcome data (n = 2) survived to admission but only one survived to discharge with good functional capacity. Of 14 with false electrical capture and outcome data, 10 (71.4%) survived to admission; none survived to discharge with functional capacity. Conclusions These findings suggest a high proportion of patients undergoing TCP are at risk of false electrical capture despite a recorded palpable pulse. While our analysis is limited to a single EMS network, these data raise concerns regarding the incidence of prehospital false electrical capture. Further research is warranted to calculate the incidence of false electrical capture and evaluate mitigation strategies.

Transvenous Pacemaker Placement: A Review for Emergency Clinicians

BackgroundTransvenous pacemaker placement is an integral component of therapy for severe dysrhythmias and a core skill in emergency medicine. ObjectiveThis narrative review provides a focused evaluation of transvenous pacemaker placement in the emergency department setting. DiscussionTemporary cardiac pacing can be a life-saving procedure. Indications for pacemaker placement include hemodynamic instability with symptomatic bradycardia secondary to atrioventricular block and sinus node dysfunction; overdrive pacing in unstable tachydysrhythmias, such as torsades de pointes; and failure of transcutaneous pacing. Optimal placement sites include the right internal jugular vein and left subclavian vein. Insertion first includes placement of a central venous catheter. The pacing wire with balloon is then advanced until electromechanical capture is obtained with the pacer in the right ventricle. Ultrasound can be used to guide and confirm lead placement using the subxiphoid or modified subxiphoid approach. The QRS segment will demonstrate ST segment elevation once the pacing wire tip contacts the endocardial wall. If mechanical capture is not achieved with initial placement of the transvenous pacer, the clinician must consider several potential issues and use an approach to evaluating the equipment and correcting any malfunction. Although life-saving in the appropriate patient, complications may occur from central venous access, right heart catheterization, and the pacing wire. ConclusionsAn understanding of transvenous pacemaker placement is essential for emergency clinicians.

Efficacy and Safety of Isoprenaline during Unstable Third-Degree Atrioventricular Block.

Unstable and symptomatic complete atrioventricular block represents a potentially fatal condition that requires prompt therapy while waiting for definitive pacemaker implantation. Although transcutaneous pacing is included in acute management, it could be a difficult approach due to its painfulness and the occasional failure of mechanical capture. Drug therapy is a feasible choice, and current guidelines encompass the use of atropine, dopamine, or epinephrine. Isoprenaline has never been investigated in this setting, and no specific indication of its use has been provided despite its potentially more favorable pharmacological profile. The study population included a consecutive series of patients who presented to the emergency department because of unstable third-degree atrioventricular block and were treated with either isoprenaline or dopamine infusion while waiting for definitive pacemaker implantation. Asymptomatic patients or those with reversible causes of complete atrioventricular block were excluded. The clinical response to the drug was deemed poor if, despite achieving a full drug dose, patients remained symptomatic and/or with hemodynamic instability, ventricular rate and rhythm did not improve or worsened, including if ventricular arrhythmias or asystolic pauses and/or irrepressible nausea/vomiting occurred. Isoprenaline infusion has proved to be safe and tolerated with no arrhythmia induction or hypotensive issues. Isoprenaline has also proven to be more satisfactory in achieving an effective clinical response in 84% of patients rather than dopamine (31%, p < 0.001), reducing the need for temporary artificial pacing. Our data point out the efficacy and safety of isoprenaline infusion and its greater tolerability over dopamine in the acute management of unstable third-degree AV block while waiting for definitive pacemaker implantation.

Reverse complete heart block using transcutaneous pacing and repeated plasmapheresis in a neonate with lupus: a case report

BackgroundIt has been reported that the complete heart block (CHB) in neonatal lupus (NL) cannot be reversed. This study reported a case of NL-CHB that was reversed by transcutaneous pacing and repeated plasmapheresis.Case presentationA 35+ 6-week male preterm baby was transferred to the neonatal intensive care unit of the Army Medical Center in May 2020 for slight cyanosis around the lips and nose. Two days after birth, a sudden decrease in heart rate was observed during electrocardiogram (EGG) monitoring. Physical examination revealed a bluish-purple discoloration around the lips and an irregular heartbeat. EGG showed the presence of isolated P (142 bpm) and QRS (78 bpm) waves, ventricular escape beats, and a diagnosis of NL-CHB. To reverse the condition, transcutaneous pacing and five sessions of plasmapheresis were performed. At a 1.5-year follow-up, the baby exhibited well-developed cardiac structure and normal neurodevelopment.ConclusionsTranscutaneous pacing and repeated plasmapheresis might be possible to reverse CHB in NL.

Transesophageal echocardiography (TEE)-guided transvenous pacing (TVP) in emergency department

BackgroundPlacement of a temporary pacemaker is a vital skill in the emergency setting in patients that present with life-threatening bradycardia. Transvenous pacing is the definitive method of stabilizing the arrhythmia compared to transcutaneous pacing, as it provides more comfort and better control of heart rate, until the insertion of a permanent pacemaker.Case reportIn this case report, we describe the steps using TEE to guide the insertion of transvenous pacer at the emergency department. Traditionally, the process of floating a transvenous pacer wire is performed “blindly” using landmarks and a monitoring ECG finding for capture, or under transthoracic echocardiography (TTE) ultrasound guidance. The blind procedure is associated with higher rate of failure and complications. While guidance using TTE is associated with higher success rates and fewer complications, inadequate imaging of the right side of the heart may limit the utility of this imaging modality. The use of transesophageal echocardiography (TEE) by emergency medicine and critical care physicians has gained traction in recent years due to its clear images and lack of interference with procedures being performed on the chest. In this article, we describe a protocol using TEE to guide the insertion of transvenous pacer through a case illustration.

Chinese emergency expert consensus on bedside temporary cardiac pacing (2023)

Temporary cardiac pacing is an essential technique in the diagnosis and treatment of arrhythmias. Due to its urgency, complexity, and uncertainty, it is necessary to develop an evidence-based emergency operation norms. Currently, there is no specific consensus guidelines at home or abroad. The Emergency Branch of Chinese Medical Association organized relevant experts to draft the Chinese emergency expert consensus on bedside temporary cardiac pacing (2023) to guide the operation and application of bedside cardiac pacing. The formulation of the consensus adopts the consensus meeting method and the evidentiary basis and recommendation grading of the Oxford Center for Evidence-based Medicine in the United States. A total of 13 recommendations were extracted from the discussion on the methods of bedside temporary cardiac pacing, the puncture site of transvenous temporary cardiac pacing, the selection of leads, the placement and placement of leads, pacemaker parameter settings, indications, complications and postoperative management. The recommended consensus includes the choice between transcutaneous and transvenous pacing, preferred venous access for temporary transvenous pacing, the target and best guidance method for implantation of bedside pacing electrodes, recommended default pacemaker settings, recommended indications for sinoatrial node dysfunction, atrioventricular block, acute myocardial infarction, cardiac arrest, ventricular and supraventricular arrhythmias. They also recommended ultrasound guidance and a shortened temporary pacing support time to reduce complications of temporary transvenous cardiac pacing, recommended bedrest, and anticoagulation after temporary transvenous pacing. Bedside temporary cardiac pacing is generally safe and effective. Accurate assessment, correct selection of the pacing mode, and timely performance of bedside temporary cardiac pacing can further improve the survival rate and prognosis of related emergency patients.

PO-04-043 ALTERNATING PR AND RP INTERVALS PRIOR TO COMPLETE AV BLOCK: THE CHICKEN OR THE EGG?

The incidence of permanent pacemaker implantation for high-degree AV block after transcatheter aortic valve replacement (TAVR) is approximately 6%, because of mechanical damage to the conduction system. We report a novel ECG marker, i.e. inverse decremental conduction (IDC), that heralds paroxysmal AV block. Case report and exploration of the electrophysiological mechanism. N/A A 73-year-old male with severe symptomatic aortic stenosis underwent TAVR with a balloon-expandable valve. On day 1 post-TAVR, his 12-lead ECG revealed sinus rhythm with a normal PR interval and unchanged RBBB with a left anterior fascicular block (LAFB). The patient was discharged with mobile cardiac outpatient telemetry. Although the patient was asymptomatic, he was asked to come to the emergency department (ED) after his monitor detected a 3.5-second pause during sleep. Shortly after a 12-lead ECG was obtained in the ED, he experienced two sudden cardiac arrests due to complete AV block and asystole requiring CPR and transcutaneous pacing. He underwent emergent implantation of a dual-chamber pacemaker. His ECG in the ED reveals alternating PR intervals (Figure). The first impression of the alternating PR intervals is a dual AV nodal physiology with a 2:1 block in the fast pathway, a relatively benign ECG sign. However, paroxysmal AV block and recent history of TAVR suggested a His-Purkinje injury with block at the subnodal level. More specifically, TAVR-related IDC in the left posterior fascicle (LPF) underlies alternating PR intervals in the setting of RBBB and LAFB. In other words, the PR length is proportional to the preceding RP length, i.e. a longer RP leads to a longer subsequent PR and vice versa due to IDC in LPF. The injured His-Purkinje fibers may lose their all-or-none conduction property and display IDC post-TAVR. This manifests as LBBB with a duration proportional to the preceding RP or RR interval or as prolongation of the PR interval with lengthening of the preceding RP interval in presence of RBBB. IDC in the His-Purkinje may be masked by decremental conduction in the AV node and is often under-recognized. Once the PR interval prolongs with lengthening of the preceding RP interval post-TAVR, unrelated to vagal stimulation, insertion of a temporary or permanent pacemaker is urgently indicated. Alternating PR intervals can be a benign finding, but in this case were linked with paroxysmal AV block secondary to IDC, with resultant cardiac arrest post-TAVR.

Self-Perceived Competence of Primary Healthcare Physicians in Managing Medical Emergencies in Health Centers; Kingdom of Bahrain: A Cross-Sectional Study

Background: Primary care physicians (PCPs) are the first point of contact for individuals when seeking healthcare and the cornerstone for providing a wide variety of preventive and curative services. Family physicians and general practitioners in primary care often encounter medical emergencies and their role in dealing with emergencies is essential to improve the patient’s outcome. Data about self-perceived competence of primary care physicians in dealing with emergencies in primary care in the Kingdom of Bahrain are lacking. This study aims at assessing the self-perceived competence of primary healthcare physicians in dealing with emergencies in primary care settings. Methods: A descriptive questionnaire-based cross-sectional study of primary healthcare family physicians and general practitioners in the Kingdom of Bahrain was conducted in January to February 2022. A total of 375 family physicians and general practitioners working in health centers were identified from Ministry of health database and 7 element anonymous self-administered electronic questionnaires were sent to their email to evaluate their level of competence in managing emergencies. Results: out of 375 PCPs; 184 (45.5%) participated and returned answered questionnaires. Most of the PCPs were females 117 (83.6%) with median age of 35 years. Regarding the level of competency in managing emergencies the majority either agreed feeling competent (37.5%) or were not sure if they feel competent in managing emergencies in primary care(37.5%).The study did not find any statistical significance or correlation between the reported competency among primary care physicians(PCPs) and age (P=0.486), years of practice(P=0.462), specialty(P=0.053), or the attended course; basic life support (BLS)(p=0.334),advanced cardiovascular life support (ACLS) (P=0.156), advanced trauma life support (ATLS)(P=0.691), pediatric advanced life support (PALS) (P=0.920).Study revealed that highest number of participants reported not feeling comfortable in dealing with major and multiple traumas in adults (n= 67, 47.86%) and pediatrics (n= 63, 45%) . The lowest level of competence in performing emergency skills was found in transcutaneous pacing, cardioversion, and nasogastric tube (NGT) insertion at which PCPs reported that they wouldn’t know how to start transcutaneous pacing (n= 67, 47.9%), while (n= 51, 36.4%) would perform cardioversion and nasogastric tube insertion (n= 43, 30.7%) only if no-one else was available. Most PCPs (n= 137, 97.9%) think that they need training in emergencies and the preferred method is practical training in health center by qualified staff (n= 122, 87.1%). Conclusion: Based on study findings, more efforts should be directed towards practical training of healthcare physicians in dealing with emergencies and the barriers should be explored. More practical training sessions should be devoted to pediatric emergencies, transcutaneous pacing, and cardioversion.

Inferior ST-Elevation Myocardial Infarction (STEMI) with Heart Block: Can We Always Trust External Pacemakers?

A 65-year-old man called emergency medical service (EMS) because of chest pain and diaphoresis. The EMS team found him hypotensive and bradycardic. His field 3-lead rhythm strip showed inferior ST-elevation myocardial infarction (STEMI) with heart block (Figure 1A). Intravenous atropine was given with no response; therefore, external transcutaneous pacing was initiated, and he was taken to the hospital (Figure 1B). However, he remained hypotensive en route.

Coronary Artery Air Embolism in the Non-operating room Anesthesia Setting.

Coronary artery air embolism is a rare complication in the non–operating room anesthesia environment. In this setting, coronary artery air embolism is generally caused by communication between the atmosphere and the pulmonary venous system or by the creation of a bronchial-venous or alveolar-venous fistula during lung biopsy.1 Typical presentation is a result of the ensuing myocardial ischemia, and includes chest pain, arrhythmia, ST segment changes, bradycardia, hypotension, and cardiovascular collapse.2Figure 1 represents the intraprocedural computed tomography imaging of a 74-year-old woman who underwent percutaneous lung biopsy. Clearly visible is the air-fluid level in the ascending aorta, just distal to the right coronary artery ostia. Figure 2 shows air in the proximal right coronary artery. This patient’s procedural course was complicated by profound bradycardia, arrhythmia, and cardiogenic shock secondary to acute myocardial ischemia.Risk of coronary artery air embolism is underappreciated outside the cardiac operating room; thus, the anesthesiologist must maintain a high degree of suspicion and closely monitor the electrocardiogram for change. Risk factors include coughing, positive pressure ventilation, biopsy of cavitary lesions, and use of needle-within-needle biopsy systems.3 In supine patients, the right ventricle is particularly vulnerable to coronary artery air embolism secondary to the anterior takeoff of the right coronary. Treatment involves immediate Trendelenburg positioning to prevent cerebral air embolism, an inspiratory oxygen fraction of 1.0, central access, and catecholamine support of cardiac function and coronary perfusion pressure. Transcutaneous or transvenous pacing, as well as coronary angiography, aspiration, and localized vasodilator injection have also been trialed successfully in the catheterization laboratory.3 Finally, extracorporeal membrane oxygenation or cardiac bypass may be indicated if other measures fail.Support was provided solely from institutional and/or departmental sources.The authors declare no competing interests.

Anteroposterior pacer pad position is better than anterolateral for transcutaneous cardiac pacing

IntroductionTranscutaneous cardiac pacing (TCP) is a lifesaving procedure for patients with certain types of unstable bradycardia. We aimed to assess the difference in the pacing thresholds between the anteroposterior (AP) and anterolateral (AL) pacer pad positions. The second aim was to characterize the severity of chest wall muscle contractions during TCP. MethodsIn this prospective crossover trial, we enrolled patients presenting to the electrophysiology laboratory for elective cardioversion. After successful cardioversion, sedated participants were sequentially paced in both positions. The study procedure concluded after successful capture or inability to achieve capture by 140 mA (the pacer’s maximum output) in both positions. Pacing thresholds were compared between positions, using a student’s paired t-test, assigning a value of 141 mA to any trials with non-capture. ResultsForty-one patients were screened; 20 were enrolled in the study. Seven participants were excluded from the paired analysis (three were prevented from pacing in the second position at the anesthesiologist’s discretion, and 4 did not capture in either position). The study population consisted of 14 men and 6 women with a median age of 65 years. The mean pacing threshold was 33 mA lower (P = 0.001, 95% CI 20–45) in the AP (93 mA) versus the AL (126 mA) position. The median contraction severity score was 3 in the AL position versus 4 in the AP position (P = 0.005). ConclusionsPlacing pacer pads in the AP position requires less energy to capture. Major resuscitation guidelines may favor the AP position for TCP.ClinicalTrials.gov Identifier: NCT03898050 https://clinicaltrials.gov/ct2/show/NCT03898050.

Abstract 10735: Brash Syndrome: Frequently Under-Recognized and Often Confused With Simple Hyperkalemia

Introduction: BRASH syndrome is a relatively newly recognized and under-reported clinical entity characterized by bradycardia, renal dysfunction, atrioventricular node blockade (AVNB), shock, and hyperkalemia. We report a case of BRASH syndrome that was refractory to medical therapy alone, requiring transvenous pacing, hemodialysis, and vasopressor support. Case presentation: An 82-year-old female with hypertension, diabetes, and paroxysmal atrial fibrillation (on metoprolol and verapamil) was found unresponsive at a nursing home. She had refractory shock (99/34 mmHg) and symptomatic bradycardia with heart rate (HR) of 33 BPM. EKG showed atrial fibrillation rhythm with ventricular rate of 31 BMP and peaked T-waves. Labs revealed creatinine of 1.98 mg/dL, potassium of 6.8 mmol/L, and TSH of 2.90 ulU/ml. She had no signs of infection and echocardiogram showed normal left ventricular systolic function. She was intubated for airway protection. AVNB agents were immediately held. Potassium-lowering agents and vasoactive drugs were administered. Temporary transvenous pacemaker was placed due to persistent bradycardia with hemodynamic instability even after transcutaneous pacing. Temporary hemodialysis was started for worsening renal failure and refractory hyperkalemia. She was weaned off vasopressor support, mechanical ventilation, hemodialysis and temporary pacing over the next few days. Renal function improved and HR stabilized at 70 BPM. Discussion: In our case, AVNB agent overdose caused bradycardia which in turn led to decreased cardiac output and renal hypoperfusion. Resultant acute kidney injury led to decreased clearance of renally excreted metoprolol and verapamil and worsening hyperkalemia, which locked the patient in a vicious cycle of BRASH syndrome leading to hemodynamic compromise. Therefore, rapid diagnosis and correct management with transvenous pacemaker and renal replacement therapy are crucial to reduce mortality.

374EMF The Ideal Transcutaneous Pacer Pad Position Study

Transcutaneous cardiac pacing is a lifesaving procedure for patients with certain types of unstable bradycardia. The American Heart Association (AHA) guidelines for the management of unstable bradycardia recommend initiating transcutaneous pacing in patients unresponsive to atropine while addressing the primary cause of the bradycardia. Current major resuscitation guidelines do not address which pacer pad position to use. The aim of this study was to assess the difference in the pacing thresholds between the anteroposterior (AP) and anterolateral (AL) pacer pad positions.

BRASH Syndrome: A Case Report and Literature Review

BRASH syndrome is a newly coined diagnosis consisting of the clinical pentad of bradycardia, renal failure, atrioventricular (AV) nodal blockade, shock, and hyperkalemia. It is a rare syndrome with just under 50 reported cases. This case report and literature review present a case of BRASH syndrome, refractory to pharmaceutical measures, and subsequent literature review to assess treatment decisions and overall outcomes. The consensus from the literature supports the use of advanced interventions in most cases, including transcutaneous or transvenous pacing, hemodialysis, and adrenergic support. The early recognition and initiation of treatment in this patient demographic are paramount to reducing possible multi-system organ damage and mortality. This case report and literature review aim to improve patient outcomes and help further elucidate a protocol for treating BRASH syndrome.