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. Author manuscript; available in PMC: 2020 Sep 19.
Published in final edited form as: Anesthesiology. 2020 May;132(5):981–991. doi: 10.1097/ALN.0000000000003176

Table 4.

Regression Coefficients with the Corresponding P Values and 95% CI for Predictors from the PACU Opioid Administration Interrupted Time Series Analysis

Predictor Effect (95% CI) P Value
Change (2 mg→1 mg) 1.55 (−0.33 to 3.43) 0.106
Change (1 mg→2 mg) 0.35 (−2.15 to 2.84) 0.784
Prechange (2 mg→1 mg) 0.00 (−0.20 to 0.20) 0.983
Postchange (2 mg→1 mg) −1.36 (−2.82 to 0.10) 0.068
Postchange (1 mg→2 mg) 2.81 (−0.14 to 5.76) 0.062
Weight, 10-kg 0.99 (0.54 to 1.44) < 0.0001
Body mass index, kg/m2 −0.15 (−0.29 to −0.01) 0.031
Age, 10-yr −1.36 (−1.59 to −1.13) < 0.0001
Sex, % male −1.37 (−2.30 to −0.44) 0.004
ASA classification −0.14 (−0.72 to 0.44) 0.647
ASA(E) −3.25 (−5.17 to −1.33) 0.001
Case duration, 60-min −0.01 (−0.02 to −0.01) < 0.0001
Ketamine −14.15 (12.49 to 15.81) < 0.0001
Acetaminophen −0.96 (−1.74 to −0.19) 0.015
Ketorolac 0.77 (−0.64 to 2.18) 0.286
Subspecialty < 0.0001
 (0 vs. 2) 9.89 (6.88 to 12.91) < 0.0001
 (1 vs. 2) 9.99 (3.44 to 16.53) 0.003
Anesthesia type < 0.0001
 (0 vs. 2) 4.36 (1.60 to 7.13) 0.002
 (1 vs. 2) −1.48 (−6.39 to 3.43) 0.556

This table displays the coefficients, 95% CI, and P values for each of the variables included in the multivariable segmented linear regression model examining the effect of hydromorphone presentation dose on postanesthesia care unit (PACU) opioid administration. The variable “Prechange (2 mg→1 mg)” represents time (per 10 weeks) before the change in hydromorphone from a 2-mg to 1-mg unit dose. The variable “Change (2 mg→1 mg)” represents the change in presentation dose from 2-mg to 1-mg unit dose. The variable “Postchange” represents time (per 10 weeks) after the change in hydromorphone from a 2-mg to 1-mg unit dose. The variable “Change (1 mg→2 mg)” represents the change in unit dose presentation from 1 mg to 2 mg. The variable “Postchange (2 mg→1 mg)” represents time (per 10 weeks) after the change from a 1-mg to 2-mg unit dose. The variable “Anesthesia type” indicates the type of anesthesia administered to the patient (i.e., general anesthesia [0], neuraxial anesthesia [1], and monitored anesthesia care [2]). The variable “Subspecialty” indicates the surgical subspecialty group to which the patient belonged (see the Materials and Methods section for description). ASA, American Society of Anesthesiologists Physical Status; ASA(E), ASA Physical Status emergency indicator.