Association between wide QRS pulseless electrical activity and hyperkalemia in cardiac arrest patients

Electrocardiographic Abnormalities in Patients with Hyperkalemia: A Retrospective Study in an Emergency Department in Colombia

Introduction

Hyperkalemia is a prevalent electrolyte disorder related to elevated serum potassium levels, resulting in diverse abnormal electrocardiographic findings and associated clinical signs and symptoms, often necessitating specific treatment. However, in some patients, these abnormal findings may not be present on the electrocardiogram even in elevated serum potassium levels. This study aims to identify electrocardiographic abnormalities related to the severity of hyperkalemia and the clinical outcomes in an emergency department in southwestern Colombia.

Methodology

This is a retrospective cross-sectional descriptive study. We described the electrocardiographic findings, clinical characteristics, treatment, and outcomes related to the degrees of hyperkalemia. The potential association between the severity of hyperkalemia and electrocardiographic findings was evaluated.

Results

A total of 494 patients were included. The median of the potassium level was 6.6 mEq/L. Abnormal electrocardiographic findings were reported in 61.5% of the cases. Mild and severe hyperkalemia groups reported abnormalities in 59.9% and 61.2%, respectively. The most common electrocardiography abnormalities were the peaked T wave 36.2%, followed by wide QRS 83 (16.8%). Only 1.4% of patients had adverse outcomes. The abnormal findings were registered in 61.5%. Mortality was 11.9%. The peaked T wave was the most common finding across different levels of hyperkalemia severity.

Conclusion

High serum potassium levels are related with abnormal ECG. However, patients with different degrees of hyperkalemia could not describe abnormal ECG findings. In a high proportion of patients with renal chronic disease and hyperkalemia, the abnormalities in the ECG could be minimal or absent.

Association Between QRS Characteristics in Pulseless Electrical Activity and Survival Outcome in Cardiac Arrest Patients: A Systematic Review and Meta-Analysis

OBJECTIVE

Recent studies have shown inconsistent results regarding the association between QRS characteristics and survival outcomes in patients with cardiac arrest and pulseless electrical activity (PEA) rhythms. This meta-analysis aimed to identify the usefulness of QRS width and frequency as prognostic tools for outcomes in patients with cardiac arrest and PEA rhythm.

METHODS

Extensive searches were conducted using Medline, Embase, and the Cochrane Library to find articles published from database inception to 4 June 2023. Studies that assessed the association between the QRS characteristics of cardiac arrest patients with PEA rhythm and survival outcomes were included. The Newcastle-Ottawa Scale was used to assess the methodological quality of the included studies.

RESULTS

A total of 9727 patients from seven observational studies were included in this systematic review and meta-analysis. The wide QRS group (QRS ≥ 120 ms) was associated with significantly higher odds of mortality than the narrow QRS group (QRS < 120 ms) (odds ratio (OR) = 1.86, 95% confidence interval (CI) = 1.11-3.11, I2 = 58%). The pooled OR for mortality was significantly higher in patients with a QRS frequency of < 60/min than in those with a QRS frequency of ≥ 60/min (OR = 1.90, 95% CI = 1.19-3.02, I2 = 65%).

CONCLUSIONS

Wide QRS width or low QRS frequency is associated with increased odds of mortality in patients with PEA cardiac arrest. These findings may be beneficial to guide the disposition of cardiac arrest patients with PEA during resuscitation.

Efficacy of emergency department calcium administration in cardiac arrest: A 9-year retrospective evaluation

BACKGROUND

The efficacy of empiric calcium for patients with undifferentiated cardiac arrest has come under increased scrutiny, including a randomized controlled trial that was stopped early due to a trend towards harm with calcium administration. However, small sample sizes and non-significant findings have hindered precise effect estimates. In this analysis we evaluate the association of calcium administration with survival in a large retrospective cohort of patients with cardiac arrest treated in the emergency department (ED).

METHODS

We conducted a retrospective review of medical records from two academic hospitals (one quaternary care center, one county trauma center) in San Francisco between 2011 and 2019. Inclusion criteria were patients aged greater than or equal to 18 years old who received treatment for cardiac arrest during their ED course. Our primary exposure was the administration of calcium while in the ED and the main outcome was survival to hospital admission. The association between calcium and survival to admission was estimated using a multivariable log-binomial regression, and also with two propensity score models.

RESULTS

We examined 781 patients with cardiac arrest treated in San Francisco EDs between 2011 and 2019 and found that calcium administration was associated with decreased survival to hospital admission (RR 0.74; 95% CI 0.66-0.82). These findings remained significant after adjustment for patient age, sex, whether the cardiac arrest was witnessed, and including an interaction term for shockable cardiac rhythms (RR 0.60; 95% CI 0.50-0.72) and non-shockable cardiac rhythms (RR 0.87; 95% CI 0.76-0.99). Risk ratios for the association between calcium and survival to hospital admission were also similar between two propensity score-based models: nearest neighbor propensity matching model (RR 0.79; 95% CI 0.68-0.89) and inverse propensity weighted regression adjustment model (RR 0.75; 95% CI 0.67-0.84).

CONCLUSIONS

Calcium administration as part of ED-directed treatment for cardiac arrest was associated with lower survival to hospital admission. Given the lack of statistically significant outcomes from smaller, more methodologically robust evaluations on this topic, we believe these findings have an important role to serve in confirming previous results and allowing for more precise effect estimates. Our data adds to the growing body evidence against the empiric use of calcium in cardiac arrest.

High-Dose Insulin for Hyperkalemic Cardiac Arrest

ABSTRACT

Hyperkalemic cardiac arrest diagnosis can be elusive and management difficult as the cardiac rhythm restoration is often not achieved until the potassium level decreases to a relatively normal level for the patient who suffers the arrest. Current treatment modalities can take hours to achieve this goal. We describe two patients who survived a witnessed hyperkalemic cardiac arrest after being managed with conventional advanced cardiac life support and unconventionally high doses of intravenous insulin.

Effect of calcium in patients with pulseless electrical activity and electrocardiographic characteristics potentially associated with hyperkalemia and ischemia-sub-study of the Calcium for Out-of-hospital Cardiac Arrest (COCA) trial

OBJECTIVE

The Calcium for Out-of-hospital Cardiac Arrest (COCA) trial was recently conducted and published. This pre-planned sub-study evaluated the effect of calcium in patients with pulseless electrical activity (PEA) including subgroup analyses based on electrocardiographic characteristics potentially associated with hyperkalemia and ischemia.

METHODS

Patients aged ≥ 18 years were included if they had a non-traumatic out-of-hospital cardiac arrest and received adrenaline. The trial drug consisted of calcium chloride (5 mmol) or saline placebo given after the first, and again after the second, dose of adrenaline for a maximum of two doses. This sub-study analyzed patients with PEA as their last known rhythm prior to receiving the trial drug. Outcomes were return of spontaneous circulation and survival at 30 days.

RESULTS

104 patients were analyzed. In the calcium group, 9 patients (20 %) achieved return of spontaneous circulation vs 23 patients (39 %) in the placebo group (risk ratio 0.51; 95 %CI 0.26, 1.00). Subgroup analyses based on electrocardiographic characteristics potentially associated with hyperkalemia and ischemia showed similar results. At 30 days, 1 patient (2.2 %) was alive in the calcium group while 8 patients (13.6 %) were alive in the placebo group (risk ratio 0.16; 95 %CI 0.02, 1.26).

CONCLUSION

In adults with out-of-hospital cardiac arrest presenting with PEA, effect estimates suggested harm of calcium administration as compared to placebo but with wide confidence intervals. Results were consistent for patients with electrocardiographic characteristics potentially associated with hyperkalemia and ischemia. The results do not support calcium administration based strictly on electrocardiographic findings seen during out-of-hospital cardiac arrest.

Sudden Cardiac Arrest in a Patient With COVID-19 as a Result of Severe Hyperkalemia After Administration of Succinylcholine Chloride for Reintubation. A Case Report

Background

We present a case study of a man with coronavirus disease 2019 (COVID-19) who developed cardiac arrest as a result of hyperkalemia following administration of chlororsuccinylcholine during endotracheal intubation.

Case Summary

A patient with a severe course of COVID-19, hospitalized in the Intensive Care Unit, underwent reintubation on day 16. The applied scheme was rapid sequence induction and intubation with administration of chlororsuccinylcholine. Immediately after intubation, there was a sudden cardiac arrest due to hyperkalemia (cK + 10.2 meq/L). Treatment was initiated as per guidelines, which resulted in a return to spontaneous circulation after 6 min.

Conclusion

Chlorsucynylcholine may cause life-threatening hyperkalemia. We recommend using rocuronium as a neuromuscular blocking agent in critically ill COVID-19 patients due to its more optimal safety profile.