Table 3.

Hazard ratios of predictor variables in base model of unplanned PICU readmission within one year^a

Patient or admission variable	HR (95% CI)	P value
Complex chronic condition
No CCC (reference)
1 CCC	2.86 (2.68–3.05)	<0.001
2 CCC	4.78 (4.48–5.1)	<0.001
≥3 CCC	9.56 (8.98–10.2)	<0.001
Age
0–1 months (reference)
2–3 months	1.13 (1.03–1.24)	0.008
4-–5 months	1.08 (0.98–1.19)	0.11
6–17 months	0.96 (0.89–1.03)	0.26
18 mon – 4 yr	0.77 (0.71–0.83)	<0.001
5–9 years	0.66 (0.61–0.72)	<0.001
10–17 years	0.76 (0.71–0.82)	<0.001
18–29 years	0.76 (0.69–0.84)	0.001
≥30 years	0.71 (0.5–0.995)	0.047
Unplanned index admission	1.46 (1.37–1.55)	<0.001
Perioperative	0.7 (0.66–0.74)	<0.001
Trauma	0.57 (0.51–0.64)	<0.001
Admitted from another institution	0.85 (0.81–0.89)	<0.001
Invasive ventilation used during admission	1.09 (1.04–1.14)	<0.001
Disposition
General ward (reference)
Intermediate/telemetry unit	1.05 (0.99–1.11)	0.1
Another ICU	0.43 (0.36–0.52)	<0.001
Operating room	0.79 (0.63–0.99)	0.04
Chronic/rehabilitation facility	0.9 (0.8–1.02)	0.1
Hospice	0.24 (0.1–0.57)	0.002
Home	0.88 (0.84–0.92)	<0.001
Other	0.51 (0.38–0.69)	<0.001
Admitted to PICU with
Pediatric beds
≤110 (reference)
111–249	1.72 (1–2.98)	0.05
≥250	2.18 (1.22–3.88)	0.008
ICU beds
≤17 (reference)
18–24	0.84 (0.63–1.13)	0.25
≥25	0.66 (0.51–0.84	0.001

CCC, complex chronic condition; CI, confidence interval; PACU, post-anesthesia care unit; ICU, intensive care unit; IQR, interquartile range; OR, odds ratio; PICU, pediatric intensive care unit

^aModel adjusted for PICU site and the unit’s average daily census by quarter at patients’ discharge, as well as PIM2 score as cubic splines.