Table 3.

Clinical outcomes of intrathecal drug delivery system (IDDS) patients and matched controls^*

Outcome	IDDS (N=112)	Control (N=209)	p-value	Covariate adjusted†
				Estimate (95% C.I.)	p-value
Opioid Utilization Outcomes
Perioperative opioid, ml OME	110 (60, 163)	93 (53, 142)	0.144	1.28 (1.03, 1.59)	0.026
Opioid first 24 hours post-PACU, ml OME	79 (23, 279)	72 (0, 209)	0.010	2.23 (1.36, 3.63)	0.001
Any opioid first 24 hours post-PACU	94 (83.9)	145 (69.4)	0.011	3.30 (1.45, 7.53)	0.005
Opioid first 72 hours post-PACU, ml OME	203 (41, 682)	128 (0, 381)	0.010	2.46 (1.41, 4.32)	0.002
Any opioid first 72 hours post-PACU	94 (83.9)	152 (72.7)	0.041	2.35 (1.08, 5.11)	0.031
Clinical Outcomes
Escalating O2 Requirement	87 (77.7)	152 (72.7)	0.458
Naloxone Administration	0 (0.0)	3 (1.4)	0.554‡
Pain-Sedation mismatch	1 (0.9)	8 (3.8)	0.169‡
Pain medicine consult	58 (51.8)	13 (6.2)	<0.001

^*Continuous outcomes are summarized using median (25^th, 75^th) and binary outcomes are summarized using n (%). Due to skewed distributions, opioid requirements were analyzed using a log transformation (log(OME + 1)). Continuous outcomes were analyzed using linear regression and binary outcomes were analyzed using logistic regression. Since multiple surgeries are included for some patients, analyses were performed using Generalized Estimating Equations (GEE) with robust variance estimates for all outcomes with the exception of naloxone administration and pain-sedation mismatch which were compared between groups using Fisher’s exact test.

^†Covariates were included for age, sex, BMI, Charlson comorbidity index, history of anxiety or depression, type of surgery, type of anesthetic, and duration of surgery. For opioid requirements expressed as a continuous variable the estimate presented corresponds to the multiplicative effect for IDDS relative to control. For binary outcomes the estimate presented corresponds to the odds ratio for IDDS relative to control.

^‡Fisher’s exact test