Table 2.

Reoperation details in propensity score–matched cohorts

	High-volume hospital (n = 142) n (%) or median (i.q.r.)	Low-volume hospital (n = 142) n (%) or median (i.q.r.)	P
Findings in reoperation*
Intra-abdominal infection	93 (65.5)	88 (62.0)	0.537
Intra-abdominal bleeding	29 (20.4)	21 (14.8)	0.213
Fascial rupture	16 (11.3)	19 (13.4)	0.588
Bowel obstruction	8 (5.6)	17 (12.0)	0.059
Wound infection (superficial)	0	7 (4.9)	0.007
No findings (negative relaparotomy)	4 (2.8)	3 (2.1)	0.211
Surgical approach
Open	127 (89.4)	121 (85.2)	0.285
Laparoscopic	5 (3.5)	6 (4.2)	0.758
Conversion	9 (6.4)	11 (7.7)	0.643
Operating time (min)†	91.0 (61.8–122.3)	90.0 (58.0–128.0)	0.912
Blood loss (ml)‡	150 (10.0–300.0)	100 (0.0–300.0)	0.300
Time to reoperation (days from index operation)	5.2 (3.2–8.6)	5.8 (3.2–9.2)	0.425
Time of day of reoperation
8–16 h	34 (23.9)	35 (24.6)	0.890
16–22 h	55 (38.7)	64 (45.1)	0.279
22–6 h	50 (35.2)	34 (23.9)	0.037
Procedures
Diversion
Protective diversion	33 (23.2)	30 (21.1)	0.645
End ileostomy	2 (1.4)	7 (4.9)	0.092
End colostomy	27 (19.0)	27 (19.0)	0.977
Anastomotic stoma	1 (0.7)	2 (1.4)	0.566
Resection of anastomosis	53 (37.3)	52 (36.6)	0.866
New anastomosis	29 (20.4)	25 (17.6)	0.526
Resuturing of anastomosis	28 (19.7)	16 (11.3)	0.046
Fascial closure	15 (10.6)	20 (14.1)	0.367
Bowel resection (other than anastomosis)	12 (8.5)	15 (10.6)	0.544
Haemostasis and/or evacuation of haematoma*	14 (9.9)	9 (6.3)	0.269
Lysis of adhesions	6 (4.2)	11 (7.7)	0.211

*Sum of percentages is over 100% as one patient may have several findings simultaneously. Bold values indicate significance (P < 0.05). †Thirteen patients were missing data for operating time (9 in LVHs and 4 in HVHs). ‡Forty-two patients were missing data for blood loss (24 in LVHs and 18 in HVHs).