End-of-life treatment and bacterial antibiotic resistance: a potential association

Great variability exists in the occurrence of antibiotic-resistant bacteria in ICUs around the world. The contribution of specific ICU care variables to these geographic variations is unknown.

ICU patients from two ICUs (in Jerusalem and Toronto) who were admitted for > 48 h and who grew a resistant bacteria in any culture during ICU admission were compared with those without resistant organisms across a range of demographic and ICU care interventions. Significant variables were investigated with logistic regression to identify factors predictive of infection/colonization with a resistant organism.

Resistant organisms were acquired by 82/423 (19%) patients. Patients acquiring a resistant organism had a higher incidence of diabetes mellitus (21/82, 26% vs 52/341, 15%; P = .026), were more frequently admitted from another ICU (17/82, 21% vs 33/341, 10%; P = .005), received more antibiotics in the ICU (19 +/- 17 vs 14 +/- 14 days; P = .005), and had more ventilator (10 +/- 10 vs 7 +/- 8; P = .031) and central line days (10 +/- 8 vs 7 +/- 8; P < .001). These patients had a lower incidence of limitation-of-therapy orders (9/82, 11% vs 78/341, 23%; P = .015). Only the absence of a limitation-of-therapy order (odds ratio, 2.62; 95% CI, 1.21-5.68; P = .014) was independently associated with the acquisition of resistant organisms. Further, among ICU fatalities, 5/45 (11%) patients acquired a resistant organism prior to withdrawal vs 17/44 (39%) nonwithdrawal fatalities (P = .003). Nonwithdrawal fatalities received significantly more third-line antibiotics (7 +/- 14 vs 2 +/- 4; P = .031) despite similar ICU lengths of stay (15 +/- 21 days for nonwithdrawal fatalities vs 10 +/- 11 for withdraw fatalities; P = .210)

End-of-life treatment is independently associated with acquisition of resistant bacteria. Patients dying without withdraw orders receive more antibiotics and develop more resistant organisms. These patients may represent a reservoir of resistant bacteria in the ICU.