Table 1.
Univariate analysis of risk factors for conversion
| Conversion (n = 84 22.5 %)a | LC (n = 289) | Total (n = 373) | OR (95% CI) | P | |
|---|---|---|---|---|---|
| Gender; Male | 48 (25.4%) | 141 (48.8%) | 189 (50.7%) | 1.4 (0.9–2.3) | 0.178 |
| Age in years, median (range) | 70 (30–92) | 61 (20–94) | 63(20–94) | NA | <0.001 |
| Heart failure | 7 (29.2%) | 17 (5.9%) | 24 (6.4%) | 1.5 (0.6–3.6) | 0.420 |
| Impaired renal function | 2 (18.2%) | 9 (3.1%) | 11 (2.9%) | 0.8 (0.2–3.6) | 1.000 |
| Diabetes | 23 (33.8%) | 45 (15.6%) | 68 (18.2%) | 2.0 (1.2–3.6) | 0.014 |
| Previous laparotomy on the upper abdomen | 8 (40.0%) | 12 (4.2%) | 20 (5.4%) | 2.4 (1.0–6.2) | 0.054 |
| Previous laparotomy on the lower abdomenb | 21 (23.9%) | 67 (24.3%) | 88 (24.6%) | 1.1 (0.6–1.9) | 0.805 |
| Previous laparoscopic surgery on the abdomenb | 7 (29.2%) | 17 (6.2%) | 24 (6.7%) | 1.4 (0.6–3.6) | 0.450 |
| No previous surgeries | 52 (21.3%) | 192 (66.4%) | 244 (65.4%) | 0.8 (0.5–1.4) | 0.442 |
| Duration of symptoms before admissionc | |||||
| < 24 h | 18 (14.4%) | 106 (40.2%) | 124 (36.9%) | 0.5 (0.3–0.9) | 0.018 |
| 24 h – 48 h | 13 (27.1%) | 35 (13.3%) | 48 (14.3%) | 1.4 (0.7–2.9) | 0.302 |
| 48 h – 72 h | 16 (25.0%) | 48 (18.2%) | 64 (19.0%) | 1.3 (0.7–2.4) | 0.439 |
| > 72 h | 25 (25.3%) | 75 (28.4%) | 100 (29.8%) | 1.3 (0.8–2.3) | 0.299 |
| Hours from admission to surgery, median (range, interquartile range) | 26 (3–109, 18–42) | 29 (3–144, 20–48) | 29 (3–144, 20–47) | NA | 0.156 |
| Total duration from symptoms onset to surgeryc | |||||
| < 24 h | 12 (21.4%) | 44 (16.7%) | 56 (16.7%) | 1.0 (0.5–2.0) | 1.000 |
| 24 h - 48 h | 8 (16.3%) | 41 (15.5%) | 49 (14.6%) | 0.7 (0.3–1.5) | 0.346 |
| 48 h - 72 h | 16 (21.3%) | 59 (22.3%) | 75 (22.3%) | 1.0 (0.5–1.9) | 0.982 |
| > 72 h | 35 (22.6%) | 120 (45.5%) | 155 (46.3%) | 1.2 (0.7–2.0) | 0.564 |
| Clinical findings | |||||
| Pain in right upper quadrant | 82 (23.1%) | 273 (94.5%) | 355 (95.2%) | 2.4 (0.5–10.7) | 0.235 |
| Guarding | 41 (25.6%) | 119 (41.2%) | 160 (42.9%) | 1.4 (0.8–2.2) | 0.213 |
| Signs of generalized peritonitis | 1 (50.0%) | 1 (0.3%) | 2 (0.5%) | 3.5 (0.2–56.0) | 0.400 |
| Palpable gallbladder | 6 (30.0%) | 14 (4.8%) | 20 (5.4%) | 1.5 (0.6–4.1) | 0.410 |
| Preoperative laboratory data, median of highest results (range, interquartile range)d | |||||
| CRP (mg/l) | 215 (3–471, 128–299) | 123 (3–524, 58–214) | 145 (3–524, 66–244) | NA | <0.001 |
| WBCC (109/l) | 14 (7–38, 12–18) | 13 (2.5–32, 10–16) | 13 (2.5–38, 10–17) | NA | 0.018 |
| ALAT (U/l) | 27 (5–222, 17–48) | 30 (4–705, 18–63) | 29 (4–705, 18–57) | NA | 0.214 |
| AFOS (U/l) | 85 (48–371, 66–126) | 80 (24–621, 61–112) | 81 (24–621, 62–113) | NA | 0.075 |
| Bilirubin (μmol/l) | 15 (4–121, 9–27) | 15 (2–230, 9–24) | 15 (2–230, 9–24) | NA | 0.668 |
| Radiographic findingse | |||||
| Abscess | 1 (100.0%) | 0 | 1 (0.3%) | NA | 0.226 |
| Free fluid | 9 (36.0%) | 16 (5.6%) | 25 (6.7%) | 2.0 (0.9–4.8) | 0.097 |
| Thickened gallbladder wall | 72 (23.2%) | 239 (83.0%) | 311 (83.6%) | 1.2 (0.6–2.4) | 0.552 |
| Preoperative ERCP | 3 (17.6%) | 14 (4.8%) | 17 (4.6%) | 0.7 (0.2–2.6) | 0.773 |
| Surgical findings | |||||
| Abscess | 10 (66.7%) | 5 (1.7%) | 15 (4.0%) | 7.7 (2.5–23.1) | <0.001 |
| Perforated gallbladder | 12 (33.3%) | 24 (8.3%) | 36 (9.7%) | 1.8 (0.9–3.9) | 0.102 |
| Gallbladder perforation during surgery | 43 (23.0%) | 144 (49.8%) | 187 (50.1%) | 1.1 (0.7–1.7) | 0.826 |
| Gangrene of the gallbladder identified by surgeon | 58 (43.0%) | 77 (26.6%) | 135 (36.2%) | 6.4 (3.6–10.4) | <0.001 |
| Removal of stones from common bile duct | 0 | 0 | 0 | NA | NA |
| Lead surgeon specialist | 32 (25.2%) | 94 (32.5%) | 126 (33.8%) | 1.3 (0.8–2.1) | 0.342 |
| Assistant present | 53 (29.9%)f | 124 (42.9%) | 177 (48.1%) | 2.7 (1.6–4.6) | <0.001 |
NA Not applicable, LC Laparoscopic cholecystectomy, OR Odds ratio, CRP C-reactive protein, WBCC White blood cell count, ERCP Endoscopic retrograde cholangiopancretography, ALAT Alanine transferase, AFOS Alkaline phosphatase
apercentages show the proportion of patients with specified risk factor
bFifteen patients had mentions of an appendectomy in their patient journals, but it was not specified whether the procedure was laparoscopic or open
cDuration of symptoms missing from 25 patients in LC and 12 in conversion
dCRP missing from one patient, ALAT missing from seven patients, AFOS missing from eight patients, bilirubin missing from 18 patients
eA total of 239 patients had an ultrasound, 65 had computed tomography (CT) and 62 had both. Magnetic resonance cholangiopancreatography (MRCP) was used in 93 patients. One patient did not undergo any imaging
fAssistant present prior to conversion, info on timing of assistant arrival missing in five cases