Patterns of daily costs differ for medical and surgical intensive care unit patients

Rationale: 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 byICU type. Objectives: To determine whether daily cost patterns differ by ICU type. Methods: We performed a retrospective study of adults admitted to five ICUs (two surgical: quaternary surgical ICU [SICUquat] and quaternary cardiac surgical ICU [CSICUquat]; two medical: tertiary medical ICU[MICUtertiary] and quaternary medical ICU [MICUquat]; one general: community medical surgical ICU [MSICUcomm]) 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. Measurements and Main Results: Unadjusted daily costs were higher on Day 1 than on subsequent days only for surgical ICUs- SICUquat (median [interquartile range], $2,636 [$1,834-$4,282] on Day 1 vs. $1,840 [$1,501-$2,332] onDay 2; P,0.001) and CSICUquat ($5,166 [$3,136-$9,493] onDay 1 vs. $2,060 [$1,336-$2,528]onDay 2; P,0.001). In nonsurgical ICUs, there was no change (MICUtertiary P = 0.12) or a small increase (MSICUcomm P=0.03;MICUquat P = 0.01) in cost from Days 1 to 2. After multivariate adjustment, there remained a significant decrease in cost from ICUDay 1 to 2 in surgical units with statistically similar Day 1 and 2 costs for other ICUs. Conclusions: Higher Day 1 costs are not seen in patients admitted to medical/nonsurgical ICUs.