Patterns of Daily Costs Differ for Medical and Surgical Intensive Care Unit Patients

Published studies suggest hospital costs on Day 1 in the intensive care unit (ICU) far exceed those of subsequent days, when costs are relatively stable. Yet, no study stratified patients by ICU type.

To determine whether daily cost patterns differ by ICU type.

We performed a retrospective study of adults admitted to five ICUs (two surgical: quaternary surgical ICU [SICU quat] and quaternary cardiac surgical ICU [CSICU quat]; two medical: tertiary medical ICU [MICU tertiary] and quaternary medical ICU [MICU quat]; one general: community medical surgical ICU [MSICU comm]) at Montefiore Medical Center in the Bronx, New York during 2013. After excluding costs clearly accrued outside the ICU, daily hospital costs were merged with clinical data. Patterns of daily unadjusted costs were evaluated in each ICU using median regression. Generalized estimating equations with first-order autocorrelation were used to identify factors independently associated with daily costs.

Unadjusted daily costs were higher on Day 1 than on subsequent days only for surgical ICUs-SICU quat (median [interquartile range], $2,636 [$1,834-$4,282] on Day 1 vs. $1,840 [$1,501-$2,332] on Day 2; P < 0.001) and CSICU quat ($5,166 [$3,136-$9,493] on Day 1 vs. $2,060 [$1,336-$2,528] on Day 2; P < 0.001). In nonsurgical ICUs, there was no change (MICU tertiary P = 0.12) or a small increase (MSICU comm P = 0.03; MICU quat P = 0.01) in cost from Days 1 to 2. After multivariate adjustment, there remained a significant decrease in cost from ICU Day 1 to 2 in surgical units with statistically similar Day 1 and 2 costs for other ICUs.

Higher Day 1 costs are not seen in patients admitted to medical/nonsurgical ICUs.