Predictive value of preoperative shock index for postoperative outcomes in traumatic splenic rupture patients undergoing splenectomy

Table 1 Comparison of basic characteristics among three groups, mean ± SD/n (%)/median (interquartile range)

Indicator	Low SI group (SI < 0.9, n = 78)	Moderate SI group (0.9 ≤ SI < 1.3, n = 89)	High SI group (SI ≥ 1.3, n = 45)	Statistic	P value	Effect size
Demographic characteristics
Age (years)	42.3 ± 15.7	45.2 ± 16.9	38.6 ± 14.2	F = 2.847	0.061	η2 = 0.027
Gender (male)	56 (71.8)	67 (75.3)	38 (84.4)	χ2 = 2.831	0.243	Cramer’s V = 0.116
BMI (kg/m2)	23.4 ± 3.2	24.1 ± 3.8	22.9 ± 3.5	F = 1.842	0.161	η2 = 0.017
BMI categories				χ2 = 5.1671	0.523	Cramer’s V = 0.111
Normal (18.5-23.9)	45 (57.7)	47 (52.8)	28 (62.2)
Overweight (24.0-27.9)	28 (35.9)	35 (39.3)	14 (31.1)
Obese (≥ 28.0)	5 (6.4)	7 (7.9)	3 (6.7)
Mechanism of injury				χ2 = 12.436	0.134	Cramer’s V = 0.171
Traffic accident	42 (53.8)	53 (59.6)	31 (68.9)
Fall from height	21 (26.9)	19 (21.3)	8 (17.8)
Heavy object impact	9 (11.5)	12 (13.5)	4 (8.9)
Sports injury	4 (5.1)	3 (3.4)	1 (2.2)
Violent injury	2 (2.6)	2 (2.2)	1 (2.2)
Time-related factors
Time from injury to admission (hours)	2.1 (1.0-4.2)	2.5 (1.2-4.8)	2.8 (1.5-5.1)	H = 3.742	0.154	ε2 = 0.018
Time from admission to surgery (hours)	4.2 (2.1-7.8)	2.8 (1.5-5.2)	1.8 (1.0-3.4)	H = 18.923	< 0.001	ε2 = 0.089
Past medical history
Hypertension	18 (23.1)	24 (27.0)	8 (17.8)	χ2 = 1.542	0.463	Cramer’s V = 0.086
Diabetes	7 (9.0)	11 (12.4)	3 (6.7)	χ2 = 1.234	0.540	Cramer’s V = 0.076
Coronary heart disease	5 (6.4)	8 (9.0)	2 (4.4)	χ2 = 1.076	0.584	Cramer’s V = 0.071
Medication history
Anticoagulant use	4 (5.1)	6 (6.7)	2 (4.4)	χ2 = 0.337	0.845	Cramer’s V = 0.040
Antiplatelet drug use	8 (10.3)	12 (13.5)	3 (6.7)	χ2 = 1.543	0.462	Cramer’s V = 0.086
Lifestyle
Smoking history	32 (41.0)	38 (42.7)	21 (46.7)	χ2 = 0.432	0.806	Cramer’s V = 0.045
Alcohol consumption history	28 (35.9)	34 (38.2)	19 (42.2)	χ2 = 0.523	0.770	Cramer’s V = 0.050

¹Linear trend χ² test.

BMI: Body mass index; SI: Shock index.