Early identification of reversible strangulating ischemia in adhesive small bowel obstruction using non-contrast computed tomography and routine laboratory parameters

Table 1 Patient characteristics, n (%)/mean ± SD

Variables	Overall population (n = 103)
Age	62.77 ± 13.06
Sex
Female	57 (55.34)
Male	46 (44.66)
BMI	22.29 ± 2.54
Neutrophil percentage	75.28 ± 7.95
ALB	41.37 ± 5.14
Fib	3.32 ± 0.87
Symptom duration (hour), M (Q1, Q3)	24.00 (24.00, 60.00)
WBC, M (Q1, Q3)	6.64 (5.12, 8.41)
PLR, M (Q1, Q3)	188.51 (134.57, 238.26)
LAC, M (Q1, Q3)	1.30 (1.02,1.80)
BE, M (Q1, Q3)	-2.00 (-3.3, -0.55)
LDH, M (Q1, Q3)	203.00 (180.00, 240.50)
CK, M (Q1, Q3)	57.00 (44.00, 90.00)
CK-MB, M (Q1, Q3)	5.00 (2.70, 8.00)
BUN, M (Q1, Q3)	6.04 (4.36, 7.29)
D-D, M (Q1, Q3)	0.72 (0.45, 1.11)
History of abdominal surgery
No	31 (30.10)
Yes	72 (69.90)
Abdominal distension
No	9 (8.74)
Yes	94 (91.26)
Nausea and vomitting
No	22 (21.36)
Yes	81 (78.64)
Cessation of flatus and defecation
No	23 (22.33)
Yes	80 (77.67)
Small bowel feces sign
No	84 (81.55)
Yes	19 (18.45)
Bowel wall thickening
No	80 (77.67)
Yes	23 (22.33)
Decreased bowel wall attenuation
No	87 (84.47)
Yes	16 (15.53)
Mesenteric haziness
No	70 (67.96)
Yes	33 (32.04)
Ascites
No	50 (48.54)
Yes	53 (51.46)
Closed-loop obstruction
No	74 (71.84)
Yes	29 (28.16)
Whirl sign
No	90 (87.38)
Yes	13 (12.62)
Mesenteric clustering
No	71 (68.93)
Yes	32 (31.07)

Data are presented as mean ± SD for normally distributed variables and median (Q₁, Q₃) for non-normally distributed variables. t: T-test; Z: Mann-Whitney test; M: Median; Q₁: 1^st quartile; Q₃: 3^st quartile; BMI: Body mass index; Fib: Fibrinogen; ALB: Albumin; WBC: White blood cell count; PLR: Platelet to lymphocyte ratio; LAC: Lactate; BE: Base excess; LDH: Lactate dehydrogenase; CK: Creatine kinase; CK-MB: Creatine kinase-MB; BUN: Blood urea nitrogen; D-D: D-dimer.

Table 2 Univariate comparison between non strangulated and strangulated ischemia, n (%)/mean ± SD

Variables	Non-strangulated (n = 74)	Strangulated ischemia (n = 29)	Statistics	P value
Age	62.96 ± 13.14	62.28 ± 13.07	t = 0.238	0.812
Sex			χ2 = 0.815	0.367
Female	43 (58.11)	14 (48.28)
Male	31 (41.89)	15 (51.72)
BMI	22.11 ± 2.41	22.74 ± 2.83	t = -1.135	0.259
N (%)	75.74 ± 8.55	74.10 ± 6.15	t = 0.939	0.35
ALB	40.42 ± 5.15	43.78 ± 4.32	t = -3.113	0.002
Fib	3.40 ± 0.86	3.12 ± 0.87	t = 1.496	0.138
Symptom duration (hour), M (Q1, Q3)	48.00 (24.00, 72.00)	24.00 (12.00, 43.00)	Z = -3.755	0.001
WBC, M (Q1, Q3)	6.30 (4.79, 8.47)	6.70 (6.26,8.17)	Z = -0.935	0.35
PLR, M (Q1, Q3)	174.00 (121.95, 227.23)	223.30 (171.15, 263.33)	Z = -2.178	0.029
LAC, M (Q1, Q3)	1.30 (1.00, 1.80)	1.40 (1.20, 1.59)	Z = -0.603	0.547
BE, M (Q1, Q3)	-1.25 (-2.80, -0.30)	-3.30 (-4.60, -2.00)	Z = -3.572	0.001
LDH, M (Q1, Q3)	207.00 (179.50, 240.00)	199.00 (181.00, 256.00)	Z = -0.073	0.942
CK, M (Q1, Q3)	56.00 (37.00, 92.50)	66.00 (56.00, 83.00)	Z = -1.320	0.187
CK-MB, M (Q1, Q3)	5.60 (2.70, 7.83)	4.09 (2.80, 8.10)	Z = -0.279	0.781
BUN, M (Q1, Q3)	5.70 (4.14, 7.27)	6.30 (4.91, 7.65)	Z = -1.030	0.303
D-dimer, M (Q1, Q3)	0.63 (0.43, 0.97)	0.98 (0.79, 1.33)	Z = -2.717	0.007
History of abdominal surgery			χ2 = 1.177	0.278
No	20 (27.03)	11 (37.93)
Yes	54 (72.97)	18 (62.07)
Abdominal distension			χ2 = 0.562	0.454
No	5 (6.76)	4 (13.79)
Yes	69 (93.24)	25 (86.21)
Nausea and vomitting			χ2 = 5.027	0.025
No	20 (27.03)	2 (6.90)
Yes	54 (72.97)	27 (93.10)
Cessation of flatus and defecation			χ2 = 1.763	0.184
No	14 (18.92)	9 (31.03)
Yes	60 (81.08)	20 (68.97)
Small bowel feces sign			χ2 = 2.241	0.134
No	63 (85.14)	21 (72.41)
Yes	11 (14.86)	8 (27.59)
Bowel wall thickening			χ2 = 0.076	0.783
No	58 (78.38)	22 (75.86)
Yes	16 (21.62)	7 (24.14)
Decreased bowel wall attenuation			χ2 = 0.362	0.547
No	64 (86.49)	23 (79.31)
Yes	10 (13.51)	6 (20.69)
Mesenteric haziness			χ2 = 25.278	0.001
No	61 (82.43)	9 (31.03)
Yes	13 (17.57)	20 (68.97)
Ascites			χ2 = 4.954	0.026
No	41 (55.41)	9 (31.03)
Yes	33 (44.59)	20 (68.97)
Closed-loop obstruction			χ2 = 22.951	0.001
No	63 (85.14)	11 (37.93)
Yes	11 (14.86)	18 (62.07)
Whirl sign			χ2 = 0.307	0.58
No	66 (89.19)	24 (82.76)
Yes	8 (10.81)	5 (17.24)
Mesenteric clustering			χ2 = 0.905	0.341
No	49 (66.22)	22 (75.86)
Yes	25 (33.78)	7 (24.14)

t: T-test; Z: Mann-Whitney test; M: Median; Q₁: 1^st quartile; Q₃: 3^st quartile; BMI: Body mass index; N (%): Neutrophil percentage; Fib: Fibrinogen; ALB: Albumin; WBC: White blood cell count; PLR: Platelet to lymphocyte ratio; LAC: Lactate; BE: Base excess; LDH: Lactate dehydrogenase; CK: Creatine kinase; CK-MB: Creatine kinase-MB; BUN: Blood urea nitrogen; D-D: D-dimer.

Table 3 Multivariable regression analysis

Variables	β	SE	Z	P value	OR	95%CI
						Low	High
Constant	-11.322	3.556	10.137	0.001
Nausea and vomitting (yes, no)	0.914	1.092	0.700	0.403	2.494	0.293	21.216
Symptom duration (hour)	-0.028	0.010	7.481	0.006	0.972	0.953	0.992
Mesenteric haziness (yes, no)	1.553	0.744	4.357	0.037	4.723	1.099	20.294
Ascites (yes, no)	1.489	0.858	3.009	0.083	4.433	0.824	23.842
Closed loop obstruction (yes, no)	1.971	0.801	6.055	0.014	7.181	1.494	34.526
ALB	0.108	0.069	2.429	0.119	1.114	0.973	1.277
PLR	0.010	0.006	2.864	0.091	1.010	0.998	1.022
BE	-0.504	0.186	7.381	0.007	0.604	0.420	0.869
D-dimer	0.907	0.617	2.160	0.142	2.476	0.739	8.294

Odds ratios and 95% confidence intervals were obtained from a multivariable regression model. Hosmer-Lemeshow = 4.978, P = 0.760 > 0.05. OR: Odds ratio; CI: Confidence interval; ALB: Albumin; PLR: Platelet to lymphocyte ratio; BE: Base excess.

Table 4 Receiver operating characteristic curve analysis of predictors

Predictors	AUC	SE	Z	P value	95%CI	Cut-off	Sensitivity (%)	Specificity (%)
Symptom duration (hour)	0.735	0.053	4.441	0.001	0.639-0.817	≤ 20	66.28	77.84
Mesenteric haziness	0.757	0.049	2.238	0.001	0.663-0.836	> 0	68.97	82.43
Closed loop obstruction	0.736	0.050	4.687	0.001	0.640-0.818	> 0	62.07	85.14
BE	0.727	0.058	3.922	0.001	0.631-0.810	≤ -3	62.07	77.38
Combined prediction	0.897	0.038	10.418	0.001	0.822-0.948	-	82.76	93.24

Cut-off values were determined using Youden’s index. AUC: Area under the curve; CI: Confidence interval; BE: Base excess.