Hospitals in which the administration of epinephrine to patients whose hearts have stopped is delayed beyond five minutes have significantly lower survival rates of those patients, a study led by a cardiologist at UT Southwestern Medical Centre finds.
Using data from a large registry, the national team of cardiologists found that nearly 13% of patients survived cardiac arrest when epinephrine shots were given within the first five minutes of the heart stopping, compared to about 11% when the epinephrine was given after five minutes, independent of all other aspects of care.
“That is a 20% better survival rate for patients at hospitals where epinephrine is given quickly, which is a big difference,” said Dr Rohan Khera, a cardiology division fellow at UT Southwestern and the first author on the study
Delays in giving the epinephrine shots also had a negative effect on functional recovery, the researchers noted. “These data are important for hospitals and patients. Improving epinephrine administration time, a likely correlate with overall CPR performance, may improve outcomes in cardiac arrest,” said Dr Mark Link, professor of internal medicine at UT Southwestern and a specialist in heart-rhythm disorders, who was not involved in the study.
Researchers reviewed more than 100,000 records of patients whose heart stopped while at the hospital, using data from a large national registry run by the American Heart Association. The review involved nearly 550 hospitals across the country.
Researchers found considerable variability in how quickly epinephrine, commonly called adrenaline, was administered among the hospitals reviewed. Although individual hospitals were not identified in the study, the data showed that hospitals treating a high volume of cardiac arrest cases tended to administer the adrenaline shots more quickly than those with a lower volume of cases.
While TV shows commonly portray doctors dramatically shocking the heart with paddles, this is not the reality for most cardiac arrest patients in hospitals. About 80% of in-hospital cardiac arrests are due to causes that cannot be addressed using a defibrillator. These non-shockable heart stoppages are treated with CPR (cardio-pulmonary resuscitation) chest compressions and epinephrine, and these non-shockable cardiac arrests have much lower survival rates.
“Treatment options for non-shockable cardiac arrest are so limited that there has been an emphasis on improving current processes,” said Khera. “Administering epinephrine promptly and improving the quality of CPR – these are the easily improved practices, which may be life-saving.”
Researchers plan to examine processes at hospitals with few delays and compare processes at hospitals with more frequent delays to see if they can identify patterns that could help speed more timely administration of adrenaline shots and whether doing so would improve survival.
Background: Patients with in-hospital cardiac arrests due to non-shockable rhythms, delays in epinephrine administration beyond 5 minutes is associated with worse survival. However, the extent of hospital variation in delayed epinephrine administration and its impact on hospital-level outcomes is unknown.
Methods: Within Get with the Guidelines-Resuscitation, we identified 103,932 adult patients (≥18 years) at 548 hospitals with an in-hospital cardiac arrest due to a non-shockable rhythm who received at least 1 dose of epinephrine between 2000 to 2014. We constructed two-level hierarchical regression models to quantify hospital variation in rates of delayed epinephrine administration (>5 minutes) and its association with hospital rates of survival to discharge and survival with functional recovery.
Results: Overall, 13,213 (12.7%) patients had delays to epinephrine, and this rate varied markedly across hospitals (range: 0% to 53.8%). The odds of delay in epinephrine administration were 58% higher at one randomly selected hospital compared to a similar patient at another randomly selected hospitals (median odds ratio [OR] 1.58; 95% C.I. 1.51 – 1.64). Median risk-standardized survival rate was 12.0% (range: 5.4% to 31.9%) and risk-standardized survival with functional recovery was 7.4% (range: 0.9% to 30.8%). There was an inverse correlation between a hospital’s rate of delayed epinephrine administration and its risk-standardized rate of survival to discharge (ρ= -0.22, P<0.0001) and survival with functional recovery (ρ= -0.14, P=0.001). Compared to a median survival rate of 12.9% (interquartile range 11.1% to 15.4%) at hospitals in the lowest quartile of epinephrine delay, risk-standardized survival was 16% lower at hospitals in the quartile with the highest rate of epinephrine delays (10.8%, interquartile range: 9.7% to 12.7%).
Conclusions: Delays in epinephrine administration following in-hospital cardiac arrest are common and varies across hospitals. Hospitals with high rates of delayed epinephrine administration had lower rates of overall survival for in-hospital cardiac arrest due to non-shockable rhythm. Further studies are needed to determine if improving hospital performance on time to epinephrine administration, especially at hospitals with poor performance on this metric will lead to improved outcomes.
Rohan Khera, Paul S Chan, Michael W. Donnino, Saket Girotra