AKI Increases Risk of Death Among Hospitalized Patients Who Experience Cardiac Arrest

Acute kidney injury (AKI) is a common outcome among patients who suffer an in-hospital cardiac arrest, and it is most often seen among men, those with preexisting chronic kidney disease, and those with a nonshockable first electrocardiogram (ECG) rhythm during resuscitation, according to a new report.

Writing in the journal Renal Failure, the authors explained that about 292,000 people suffer in-hospital cardiac arrest each year in the United States, and incidence rates have been rising. Many patients who experience cardiac arrest also receive an AKI diagnosis, and patients with AKI tend to have poorer outcomes, said the investigators, all of whom were affiliated with University Hospital Frankfurt, in Germany.

Patients who recover from AKI, however, have better outcomes, they added.

Given its potential impact on patient prognosis, the authors wanted to better understand the incidence, risk factors, and prognosis associated with AKI following in-hospital cardiac arrest. They retrospectively analyzed a cohort of adults who experienced in-hospital cardiac arrest at a single German health care center between 2006 and 2014. In total, 238 in-hospital cardiac arrest events were reported. The majority (89.9%) were patients of the hospital’s Internal Medicine department; the remaining 10.1% were patients from other departments, including the Surgical and Neurological departments.

Just over half of the patients (120 patients) received an AKI diagnosis, mostly classified as stage I and II AKI, according to the Acute Kidney Injury Network classification scale. Twenty-eight patients needed transient or permanent renal replacement therapy. An additional 15 patients had been on chronic renal replacement therapy prior to their cardiac arrest.

Forty-five percent (108 patients) of those who survived their in-hospital cardiac arrest died before they could be released from the hospital. However, among the 120 patients who also had AKI, 73 patients died during their hospital stays, for an all-cause mortality rate of 60.8%. Among the 118 patients who did not suffer AKI, the all-cause mortality rate was just 29.7%.

The authors assessed the group to see which factors might correlate with a higher likelihood of AKI, and their findings echoed previous research.

“As shown before in other studies, our data reveal that age, duration of CPR, and a shockable first rhythm on ECG during resuscitation had an influence on the incidence of AKI in this study population,” they wrote. “However, only a nonshockable rhythm at first ECG documentation could be confirmed as an independent predictor of AKI.”

The likely reasons for the correlations are that patients who could quickly be revived would have experienced shorter periods of shock and less-pronounced cardiac arrest syndrome, the authors said.

The retrospective nature of the study made it difficult to draw conclusions about the ways in which postºcardiac arrest therapy might affect the development of AKI. However, the authors said the existing data suggest rapid intervention for cardiac arrest is an important piece of the puzzle.

“Fast and effective onset of resuscitation is suggested to be a cornerstone of AKI prevention in order to improve prognosis in these seriously ill patients’ population,” they said. “Whether specific post–resuscitation therapy regimens can reduce incidence of AKI in these patients has to be investigated in further studies.”

Reference

Patyna S, Riekert K, Buettner S, et al. Acute kidney injury after in-hospital cardiac arrest in a predominant internal medicine and cardiology patient population: incidence, risk factors, and impact on survival. Ren Fail. 2021;43(1):1163-1169. doi:10.1080/0886022X.2021.1956538