A decision rule to aid selection of patients with abdominal sepsis requiring a relaparotomy

BMC Surgery

Table 2 Odds ratios (OR) and 95% confidence intervals (CI) of the variables entered in the multivariable logistic regression and after backward selection to predict the need for a relaparotomy in patients with secondary peritonitis

Variable	Full model		Backward elimination^a
	OR	95% CI	OR	95% CI
Heart rate > 90 bpm	1.61	0.57-4.53	1.97	0.75-5.17
Central venous pressure^b	1.01	0.92-1.10	Dropped
Lactate^b,c	1.22	0.59-2.52	Dropped
Platelet count < 150 x 10⁹/L	1.51	0.58-3.91	Dropped
Hemoglobin < 5.0 mmol/L (8.1 g/dl)	3.23	1.07-9.76	2.99	1.10-8.10
Temperature <35.5 or >39.0°C	2.51	0.86-7.34	2.50	0.95-6.56
Administration of inotropic agents	4.99	1.80-13.84	4.09	1.66-10.07
No defecation	5.86	1.93-17.75	4.35	1.55-12.16
Diffuse contamination at initial operation	1.90	0.74-4.84	2.15	0.91-5.09
Etiology of peritonitis
- inflammation	5.20	0.51-53.47	Dropped
- perforation	1.00	reference
- ischemia/necrosis	0.32	0.03-3.45
- anastomotic leakage	1.64	0.62-4.34
Elimination of infectious focus at initial operation	2.98	0.49-18.17	Dropped

^a Corrected for over fitting, values of final model.
^b Continues variable, OR per unit increase in lactate (mmol/L) and central venous pressure (mmHg).
^c Logarithmic transformation.

ISSN: 1471-2482