Cardiac arrest patients in Finnish intensive care units: insights into incidence, long-term outcomes and costs

Background: Sudden cardiac arrest (CA) represents a significant cause of death worldwide. Inhospital patients carry a particularly high risk of CA, both on the general ward and in the intensive care unit (ICU). With over 10,000 CAs occurring daily globally, undoubtedly CA has a significant socioeconomic impact. However, data on in-hospital CA (IHCA) and CA-related healthcare costs in Finland and globally, remain limited. Critically ill patients are often admitted to ICUs to undergo complex treatments that may or may not influence patient outcomes. Yet, changes in treatment intensity can potentially reflect a specific patient’s clinical condition and carry additional prognostic value. Aims: This study aimed to systematically review published literature on in-ICU CA (ICUCA), to investigate outcomes and healthcare-associated costs for CA patients treated within Finnish ICUs and to explore the individual effects of early treatment intensity and cardiopulmonary resuscitation on hospital mortality amongst Finnish ICU patients. Methods: The study consisted of a systematic review of the published literature (study I) summarising scientific evidence on CA in critically ill patients, and three original substudies on patients treated in Finnish ICUs between 2003 and 2013. The data for the substudies were acquired from the databases of the Finnish Intensive Care Consortium (FICC), the Social Insurance Institution of Finland (SII) and the Finnish Population Register Centre. Cost data comprised index hospitalisation expenses, rehabilitation costs and social security costs up to one year after CA. Effective cost per one-year survivor reflected the economic impact of CA, calculated as the sum of the total of healthcare costs divided by the number of survivors. Results: Across substudies, patient population size varied from n = 1024 to n = 164,255. A systematic review of the literature analysed 18 studies published between 1990 and 2013. Most of the reviewed publications were single-centre and retrospective with highly variable incidence and the outcome of ICU-CA. In Finland, there were 29 ICU-CAs for every 1000 ICU admissions. ICU-CA hospital mortality reached 56%. Amongst CA patients treated in a tertiary teaching hospital ICUs, 58% of out-of-hospital CA (OHCA) patients, 41% of IHCA patients and 39% of ICU-CA patients remained alive at one year following the initial arrest, of these 88% to 94% had a favourable neurological outcome. The effective cost, expressed in 2013 euro, was €94,688 for a one-year ICU-treated CA survivor and €102,722 for a one-year survivor with a favourable neurological outcome. A CA event and poor preadmission functional status were associated with a similar increase in the risk of hospital mortality. An increase in the intensity of early treatment associated with a higher risk of in-hospital death, particularly amongst patients with an initially low mortality risk. Conclusions: The incidence of ICU-CA amongst Finnish critically ill patients was higher and mortality was lower than previously published findings. The effective costs for one-year survivors were comparable to or lower than costs for ICU-treated patients with acute renal failure and critically ill cancer patients, healthcare expenditures considered generally acceptable. The increase in the risk of in-hospital death due to CA was comparable in magnitude to a poor preadmission functional status. Early increase in treatment intensity can serve as an additional warning sign of deterioration in Finnish critically ill patients.