Overuse of arterial blood gas (ABG) determinations leads to increased costs, inefficient use of staff work hours, and patient discomfort and blood loss. We developed guidelines to optimize ABG use in the ICU.
ABG use guidelines were implemented in all adult ICUs in our institution: three medical, two trauma-surgery, one cardiovascular, and one neurosurgical ICU. Although relying on pulse oximetry, we encouraged the use of ABG determination after an acute respiratory event or for a rational clinical concern and discouraged obtaining ABG measurements for routine surveillance, after planned changes of positive end-expiratory pressure or Fio2 on the mechanical ventilator, for spontaneous breathing trials, or when a disorder was not suspected. ABG measurements and global ICU metrics were collected before (year 2014) and after (year 2015) the intervention.
We saw a reduction of 821.5 ± 257.4 ABG determinations per month (41.5%), or approximately one ABG determination per patient per mechanical ventilation (MV) day for each month (43.1%), after introducing the guidelines (P < .001). This represented 49 L of saved blood, a reduction of $39,432 in the costs of ICU care, and 1,643 staff work hours freed for other tasks. Appropriately indicated tests rose to 83.4% from a baseline 67.5% (P = .002). Less than 5% of inappropriately indicated ABG determinations changed patient management in the postintervention period. There were no significant differences in MV days, severity of illness, or ICU mortality between the two periods.
The large scale implementation of guidelines for ABG use reduced the number of inappropriately ordered ABG determinations over seven different multidisciplinary ICUs, without negatively impacting patient care.