Critical Care in the Military Health System: A 24-h Point Prevalence Study

Healthcare expenditures are a significant economic cost with critical care services constituting one of its largest components. The Military Health System (MHS) is the largest, global healthcare system of its kind. In this project, we sought to describe critical care services and the patients who receive them in the MHS.

We surveyed 26 military treatment facilities (MTFs) representing 38 critical care services or intensive care units (ICUs). MTFs with multiple ICUs and critical care services responded to the survey as services (e.g., surgical or medical ICU service), whereas MTFs with only one ICU responded as a unit and gave information about all types of patients (i.e., medical and surgical). Our survey was divided into an administrative portion and a 24-h point prevalence survey of patients and patient care. The administrative portion is reported separately in this journal. The 24-h point prevalence survey collected information about all patients present in, admitted to, or discharged from participating services/units during the same 24-h period in December 2014. The survey was anonymous and protected health information was not collected.

Sixteen MTFs (69%) and 27 ICU services/units (71%) returned the point prevalence survey. MTFs with >200 beds (n = 3, 22%) were categorized as "high capacity centers" (HCCs) whereas those with ≤200 beds (n = 13, 78%) were characterized as low capacity centers (LCCs). Two MTFs (one HCC and one LCC) returned only administrative data. The remaining 16 MTFs reported data about 151 patients. In all, 100 (67%) of the patients were at three HCCs during this study period. One HCC accounted for 39% (59 patients) of all patient care during this study. Most patients were cared for in mixed medical/surgical ICUs (34.4%), followed by medical (21.2%), surgical (18.5%), trauma (11.9%), cardiac (7.9%), and burn (6.0%) ICUs. The most common medical indication for admission was cardiac followed by general medical. The most common surgical indications for admission were trauma, other, and cardiothoracic surgery. The average APACHE II score of all patients across both LCCs and HCCs was 11 ± 8.1 (8 ± 7.8 vs. 13 ± 7.7 p = 0.008). The lower acuity of patients in this study is reflected in a high turnover rate, low rate of arterial and central line placements (33%), and low rates of life support (all types, 30%; mechanical ventilation only, 21.2%; noninvasive mechanic ventilation only, 7.9%; and vasoactive medications, 6.6%). Thirty-five (23.2%) patients within the study were affected by a total of 57 complications. The three most common complications experienced were acute kidney injury, bleeding, and sepsis.

This is the first detailed report about MHS critical care services and the patients receiving care. It describes a low acuity ICU patient population, concentrated at larger MTFs. This study highlights the need for the establishment of a system that allows for the continuous collection of high priority information about clinical care in the MHS in order to facilitate implementation of standardized protocols and process improvements.