Clinical and electrocardiogram presentations of patients with high serum potassium concentrations within emergency settings: a prospective study

Abstract

Background Elevated potassium level is a common and reversible peri-arrest condition. Diagnosis and management of hyperkalemia in a short time is critical, where electrocardiogram (ECG) alterations might be helpful. We aimed to investigate the role of clinical features and ECGs in early diagnosing and treating hyperkalemia. Methods Prospectively, adult patients who presented to the emergency department (ED) from July 2019 to March 2020 with hyperkalemia (serum potassium ≥5.5mmol/L) were included. History was obtained, and laboratory investigations and ECGs were performed at the presentation and before initiating hyperkalemia therapy. Hyperkalemia severity was divided into mild (5.5–5.9mmol/L), moderate (6.0–6.4mmol/L), and severe (≥6.5mmol/L). A cardiologist and emergency physician blinded to laboratory values, study design, and patients’ diagnoses interpreted ECGs and presenting symptoms independently to predict hyperkalemia. Results Sixty-seven hyperkalemic patients with a mean (±SD) serum potassium level of 6.5±0.7mmol/L were included in this study. The mean age was 63.9±15.1, and 58.2% were females. Hyperkalemia was mild in 10.4%, moderate in 40.3%, and severe in 49.3%. Almost two thirds of patients (71.6%) had hypertension, 67.2% diabetes, and 64.2% chronic kidney disease. About one-quarter of patients (22.4%) were asymptomatic, while fatigue (46.3%), dyspnea (28.4%), and nausea/vomiting (20.9%) were the most common presenting symptoms. Normal ECGs were observed in 25.4% of patients, while alterations in 74.6%. Atrial fibrillation (13.4%), peaked T wave (11.9%), widened QRS (11.9%), prolonged PR interval (10.5%), and flattening P wave (10.5%) were the most common. Peaked T wave was significantly more common in severe hyperkalemia (87.5%) than in mild and moderate hyperkalemia (12.5%, 0.0%, respectively) (p=0.041). The physicians’ sensitivities for predicting hyperkalemia were 35.8% and 28.4%, improved to 51.5% and 42.4%, respectively, when limiting the analyses to severe hyperkalemia. The mean (±SD) time to initial hyperkalemia treatment was 63.8±31.5 min. Potassium levels were positively correlated with PR interval (r=0.283, p=0.038), QRS duration (r=0.361, p=0.003), peaked T wave (r=0.242, p=0.041), and serum levels of creatinine (r=0.347, p=0.004), BUN (r=0.312, p=0.008), and CK (r=0.373, p=0.039). Conclusions The physicians’ abilities to predict hyperkalemia based on ECG and symptoms were poor. ECG could not be solely relied on, and serum potassium tests should be conducted for accurate diagnosis.

Timing of Initiation of Kidney Replacement Therapy in Acute Kidney Injury in the Critically Ill Patient

“…In a prospective study [32] of 77 patients that included both AKI and CKD, 94% associated with a fall in eGFR and 70.9% had metabolic acidosis, 10.4% developed mild (5.5-5.9 mmol/L), moderate 40.3% (6-6.4 mmol/L), and severe hyperkalemia 49.3% (>6.5 mmol/L); electrocardiographic changes occurred in 74.6% of patients, the most frequent findings being atrial fibrillation (13.4%), peaked T wave (11.9%), widened QRS, and prolonged PR (10.5%); none of these electrocardiographic findings were more significant with greater severity. The sensitivity in the electrocardiographic detection of hyperkalemia was 0.28 for the emergency physician and 0.36 for the cardiologist.…”

CE: Tumor Lysis Syndrome: An Oncologic Emergency

“…Other changes may include a widened QRS complex, prolonged PR interval, flattening of P waves, and ST-segment depression. [10][11][12] (See Figure 1.)…”

“…I t's important for nurses to be aware of both patient and cancer characteristics that put patients at elevated risk for tumor lysis syndrome and to closely observe patients for early signs and symptoms of the condition, which are both subtle and common in oncology patients, and include nausea, vomiting, dyspnea, fatigue, muscle spasm, and paresthesia. 5,11 Awareness of tumor lysis syndrome risk factors, initial signs and symptoms, and time of symptom onset can help nurses differentiate tumor lysis syndrome from other causes. While early signs and symptoms may be evident within a few hours after chemotherapy is started, they more commonly occur 24 to 48 hours following its initiation.…”

“…It's important for nurses to be aware of both patient and cancer characteristics that put patients at elevated risk for tumor lysis syndrome and to closely observe patients for early signs and symptoms of the condition, which are both subtle and common in oncology patients, and include nausea, vomiting, dyspnea, fatigue, muscle spasm, and paresthesia 5, 11…”

“…13 (For common signs and symptoms of electrolyte imbalances that occur in tumor lysis syndrome, see Table 2. 5,[10][11][12][14][15][16][17] )…”