Adverse Events in Pediatric Critical Care Nonsurvivors With a Low Predicted Mortality Risk: A Multicenter Case Control Study

Abstract

Objectives: Some patients with a low predicted mortality risk in the PICU die. The contribution of adverse events to mortality in this group is unknown. The aim of this study was to estimate the occurrence of adverse events in low-risk nonsurvivors (LN), compared with low-risk survivors (LS) and high-risk PICU survivors and nonsurvivors, and the contribution of adverse events to mortality.

Design: Case control study. Admissions were selected from the national Dutch PICU registry, containing 53,789 PICU admissions between 2006 and 2017, in seven PICUs. PICU admissions were stratified into four groups, based on mortality risk (low/high) and outcome (death/survival). Random samples were selected from the four groups. Cases were "LN." Control groups were as follows: "LS," "high-risk nonsurvivors" (HN), and "high-risk survivors" (HS). Adverse events were identified using the validated trigger tool method.

Setting: Patient chart review study.

Patients: Children admitted to the PICU with either a low predicted mortality risk (< 1%) or high predicted mortality risk (≥ 30%).

Interventions: None.

Measurements and main results: In total, 419 patients were included (102 LN, 107 LS, 104 HN, and 106 HS). LN had more complex chronic conditions (93.1%) than LS (72.9%; p < 0.01), HN (49.0%; p < 0.001), and HS (48.1%; p < 0.001). The occurrence of adverse events in LN (76.5%) was higher than in LS (13.1%) and HN (47.1%) ( p < 0.001). The most frequent adverse events in LN were hospital-acquired infections and drug/fluid-related adverse events. LN suffered from more severe adverse events compared with LS and HS ( p < 0.001). In 30.4% of LN, an adverse event contributed to death. In 8.8%, this adverse event was considered preventable.

Conclusions: Significant and preventable adverse events were found in low-risk PICU nonsurvivors. 76.5% of LN had one or more adverse events. In 30.4% of LN, an adverse event contributed to mortality.

Figure 1.

Flowchart of the study. ^aIn total, 43 of 35,168 admissions had discrepancies between the mortality prediction models: they were low risk in one model and high risk in the second model, therefore fulfilling criteria for both low-risk and high-risk (e.g. “low-risk according to PIM2 and simultaneously high-risk according to PRISM”). Four admissions both LN and HN. Thirty-nine admissions both LS and HS. HN = high-risk nonsurvivors, HS = high-risk survivors, LN = low-risk nonsurvivors, LS = low-risk survivors, PIM2 = Pediatric Index of Mortality 2, PRISM = Pediatric Risk of Mortality.