Possible Predictive Factors for In-hospital Cardiac Arrest in Patients with Cancer: A Retrospective Single Center Study

Background: Despite cancer being the second most common cause of death in the United States, more people are living longer after the diagnosis of cancer than before. Healthcare workers will be treating an increasing number of patients with cancer. Various studies have identified predictors of cardiac arrest in the general population, however, none have been done to identify such factors in cancer patients who form a more vulnerable group with lower survival rate following cardiac arrest. Methods: We retrospectively analysed charts of all patients with active cancer who experienced in-hospital cardiac arrest (IHCA) and underwent cardio-pulmonary resuscitation (CPR) from January 2015 to December 2017 at our hospital (n=44, group A). We compared this group to 44 consecutive patients with active cancer admitted to the oncology unit who did not experience cardiac arrest (n=44, group B). We excluded patients in remission. Results: Both the groups were comparable in terms of age (69 +/- 14 vs 68 +/- 15, p=0.776) and gender distribution (50% vs 56% males, p=0.521). Prevalence of coronary artery disease (CAD) (25% vs 11%, p=0.097), hypertension (68% vs 66%, p=0.821), hyperlipidaemia (34% in both groups, p= 1.000), tobacco abuse (18% vs 27%, p=0.308), and diabetes mellitus (34% vs 23%, p=0.237) was not significantly different between the two groups. Group with cardiac arrest had significantly higher alanine aminotransferase (100 U/L +/- 150 vs 47 U/L +/- 87, p= 0.043), alkaline phosphatase (288 U/L +/- 512 vs 118 U/L +/- 80, p= 0.032), creatinine (1.8 mg/dl +/- 1.74 vs 1.1 mg/dl +/- 0.76, p=0.023), international normalised ratio (INR) (2.1 +/- 1.5 vs 1.2 +/- 0.5, p=0.005), and lower estimated -glomerular filtration rate (43 mL/min/1.73m(2) +/- 17 vs 51 mL/min/1.73m2 +/- 15, p=0.022) on admission. Group A also had significantly higher incidence of sepsis during the hospital course as compared to group B (30% vs 2%, p<0.001). In group A, 11.4% survived to discharge as compared to 95.5% in group B. Significantly higher number of patients in group B were taking chemotherapy (77.27% vs 34.09%, p=0.000046) and radiation therapy (65.9% vs 22.72%, p=0.000046) as compared to group A. Conclusion: Cancer patients who experienced IHCA had worse renal and hepatic function; they were frequently diagnosed with sepsis and had similar cardiovascular risk factors as compared to cancer patients who did not experience cardiac arrest. Furthermore, a higher number of patients with active cancer who did not experience cardiac arrest were on chemotherapy, immunotherapy or radiation therapy.