Preoperative albumin levels predict prolonged postoperative ileus in gastrointestinal surgery

Table 1 Correlation between preoperative albumin and clinicopathologic variables in patients undergoing gastrointestinal surgery

Characteristics	Total cohort	Subgroups of preoperative albumin		P value
	n = 311	< 39.15, n = 135	≥ 39.15, n = 176
Sex				0.364
Female	93 (29.90%)	44 (32.59%)	49 (27.84%)
Male	218 (70.10%)	91 (67.41%)	127 (72.16%)
Age (yr)	58.98 ± 10.98	60.52 ± 10.77	57.80 ± 11.03	0.030
Categorical variable				0.007
< 60	156 (50.16%)	56 (41.48%)	100 (56.82%)
≥ 60	155 (49.84%)	79 (58.52%)	76 (43.18%)
Body mass index (kg/m2)	24.43 ± 3.23	24.14 ± 3.11	24.65 ± 3.31	0.173
Categorical variable				0.136
< 25	174 (55.95%)	82 (60.74%)	92 (52.27%)
≥ 25	137 (44.05%)	53 (39.26%)	84 (47.73%)
Previous abdominal surgery				0.178
No	252 (81.03%)	114 (84.44%)	138 (78.41%)
Yes	59 (18.97%)	21 (15.56%)	38 (21.59%)
Preoperative albumin (g/L)	39.77 ± 3.67	36.46 ± 2.33	42.30 ± 2.19	< 0.001
Preoperative K+ (mmol/L)	3.96 ± 0.32	3.94 ± 0.34	3.98 ± 0.31	0.306
Categorical variable				0.948
< 3.96	155 (49.84%)	67 (49.63%)	88 (50.00%)
≥ 3.96	156 (50.16%)	68 (50.37%)	88 (50.00%)
Type of cancer				0.701
Gastric cancer	162 (52.09%)	72 (53.33%)	90 (51.14%)
Colorectal cancer	149 (47.91%)	63 (46.67%)	86 (48.86%)
Surgical technique				0.868
Endoscopic surgery	215 (69.13%)	94 (69.63%)	121 (68.75%)
Open surgery	96 (30.87%)	41 (30.37%)	55 (31.25%)
Tumor stage				0.094
I-II	133 (43.46%)	65 (48.87%)	68 (39.31%)
III-IV	173 (56.54%)	68 (51.13%)	105 (60.69%)
Postoperative opioid analgesic				0.983
No	191 (61.41%)	83 (61.48%)	108 (61.36%)
Yes	120 (38.59%)	52 (38.52%)	68 (38.64%)
PPOI				0.028
No	244 (78.46%)	98 (72.59%)	146 (82.95%)
Yes	67 (21.54%)	37 (27.41%)	30 (17.05%)

Data are presented as number of patients or mean ± standard error. PPOI: Prolonged postoperative ileus.

Table 2 Univariate analysis of the potential clinicopathologic variables of Prolonged postoperative ileus

Characteristics	Without PPOI	With PPOI	Univariate	P value
	(n = 244)	(n = 67)	OR (95%CI)
Sex				0.362
Female	76 (81.72%)	17 (18.28%)	Ref.
Male	168 (77.06%)	50 (22.97%)	1.33 (0.72, 2.46)
Age (yr)				0.867
< 60	123 (78.58%)	33 (21.15%)	Ref.
≥ 60	121 (78.06%)	34 (21.94%)	1.05 (0.61, 1.80)
Body mass index (kg/m2)				0.886
< 25	136 (78.16%)	38 (21.84%)	Ref.
≥ 25	108 (78.83%)	29 (21.17%)	0.96 (0.56, 1.66)
Previous abdominal surgery				0.803
No	197 (78.17%)	55 (21.83%)	Ref.
Yes	47 (79.66%)	12 (20.34%)	0.91 (0.45, 1.84)
Preoperative albumin (g/L)				0.029
< 39.15	98 (72.59%)	37 (27.41%)	Ref.
≥ 39.15	146 (82.95%)	30 (17.05%)	0.54 (0.32, 0.94)
Preoperative K+ (mmol/L)				0.701
< 3.96	123 (79.35%)	32 (20.65%)	Ref.
≥ 3.96	121 (77.56%)	35 (22.44%)	1.11 (0.65, 1.91)
Type of cancer				0.424
Gastric cancer	130 (80.25%)	32 (19.75%)	Ref.
Colorectal cancer	114 (76.51%)	35 (23.49%)	1.25 (0.73, 2.14)
Surgical technique				0.839
Endoscopic surgery	168 (78.14%)	47 (21.86%)	Ref.
Open surgery	76 (79.17%)	20 (20.83%)	0.94 (0.52, 1.70)
Tumor stage				< 0.001
I-II	118 (88.72%)	15 (11.28%)	Ref.
III-IV	121 (69.94%)	52 (30.06%)	3.33 (1.81, 6.25)
Postoperative opioid analgesic				< 0.001
No	164 (85.86%)	27 (14.14%)	Ref.
Yes	80 (66.67%)	40 (33.33%)	3.04 (1.74, 5.30)

PPOI: Prolonged postoperative ileus; OR: Odds ratio; CI: Confidence Interval.

Table 3 Association between perioperative albumin and prolonged postoperative ileus by multiple regression analysis in different models

Models	Crude model	P value	Model I	P value	Model II	P value
Preoperative albumin (g/L)	OR (95%CI)		OR (95%CI)		OR (95%CI)
Continuous variable
Per unit	0.95 (0.88, 1.02)	0.174	0.95 (0.88, 1.02)	0.155	0.92 (0.85, 1.00)	0.046
Per SD (3.67)	0.83 (0.63, 1.09)	0.174	0.82 (0.62, 1.08)	0.155	0.73 (0.54, 0.99)	0.046
Categorical variable
< 39.15	Ref.		Ref.		Ref.
≥ 39.15	0.54 (0.32, 0.94)	0.029	0.53 (0.31, 0.92)	0.025	0.43 (0.24, 0.78)	0.006

Crude model covariants were not adjusted; Model I minimally adjusted for sex, age and body mass index (BMI); Model II fully adjusted for sex, age, BMI, type of cancer, surgical technique, tumor stage and use of a postoperative opioid analgesic. PPOI: Prolonged postoperative ileus; OR: Odds ratio; CI: Confidence Interval: SD: Standard error.