Intraoperative immunomodulatory effects of sevoflurane versus total intravenous anesthesia with propofol in bariatric surgery (the OBESITA trial): study protocol for a randomized controlled pilot trial

Table 1 Independent predictors of risk for PPCs identified in the logistic regression model (ARISCAT score)

	Multivariate analysis OR (95% CI) n = 1.624*	β	Risk score^a
Age, years
≤ 50	1
51–80	1.4 (0.6–3.3)	0.331	3
> 80	5.1 (1.9–13.3)	1.619	16
Preoperative SpO₂, %
≥ 96	1
91–95	2.2 (1.2–4.2)	0.802	8
≤ 90	10.7 (4.1–28.1)	2.375	24
RTI in preceding month	5.5 (2.6–11.5)	1.698	17
Preoperative anemia (Hb ≤ 10 g/dL)	3.0 (1.4–6.5)	1.105	11
Surgical incision
Peripheral	1
Upper abdomen	4.4 (2.3–8.5)	1.480	15
Intrathoracic	11.4 (4.9–26.0)	2.431	24
Duration of surgery, hours
≤ 2	1
> 2–3	4.9 (2.4–10.1)	1.593	16
> 3	9.7 (4.7–19.9)	2.268	23
Emergency procedure	2.2 (1.0–4.5)	0.768	8

Three patients were excluded because of a missing value for some variables. Logistic regression model constructed with the development subsample, c-index = 0.90; Hosmer-Lemeshow chi-square test = 7.862; P = 0.447
CI confidence interval, Hb hemoglobin, OR odds ratio, PPC postoperative pulmonary complications, RTI respiratory tract infection, SpO2 oxyhemoglobin saturation by pulse oximetry (breathing room air in the supine position)
^aSimplified risk score was the sum of each logistic regression coefficient (β) multiplied by 10, after rounding off