Operative complications and economic outcomes of cholecystectomy for acute cholecystitis

Table 1 Demographics and patient characteristics

Variable	Same admission cholecystectomy	Delayed cholecystectomy	P value
	(n = 486), n (%) or mean ± SD	(n = 68), n (%) or mean ± SD
Age at surgery	44.7 ± 16.0	45.2 ± 15.7	0.812
Female	280 (64.8)	49 (74.2)	0.132
Race/ethnicity			0.447
White	183 (42.5)	35 (53.0)
Black	57 (13.2)	7 (10.6)
Hispanic	185 (42.9)	23 (34.9)
Other	6 (1.4)	1 (1.5)
Body mass index	32.2 ± 15.6	32.1 ± 6.4	0.93
Comorbidities
Coronary artery disease	13 (3.0)	2 (3.0)	1
Myocardial infarction	1 (0.2)	0 (0.0)	1
Diabetes	35 (8.1)	4 (6.1)	0.565
Hypertension	80 (18.5)	18 (27.3)	0.096
Chronic obstructive pulmonary disease	3 (0.7)	1 (1.5)	0.435
Alcohol use	134 (42.8)	27 (46.6)	0.598
Smoking status	100 (26.1)	20 (31.3)	0.39
Open cholecystectomy	8 (1.7)	3 (4.4)	0.142
Convert-to-open cholecystectomy	7 (1.4)	2 (2.9)	0.305

Table 2 Stratification by disease severity using 2013/18 Tokyo guidelines, n (%)

	Same admission cholecystectomy, n = 486	Delayed cholecystectomy, n = 68	P value
Acute cholecystitis severity
Tokyo Grade 1	299 (61.5)	36 (52.9)	0.271
Tokyo Grade 2	174 (35.8)	31 (45.6)
Tokyo Grade 3	13 (2.7)	1 (1.5)
Tokyo criteria	mean ± SD	mean ± SD
White blood cell count	11.8 ± 4.5	11.4 ± 3.8	0.605
Duration of complaints	1.9 ± 7.3	1.4 ± 3.2	0.578
Palpable tender mass in RUQ	8 (1.6)	1 (1.5)	1
Marked local inflammation	66 (13.6)	13 (19.1)	0.221
Creatinine	0.9 ± 0.8	0.7 ± 0.2	0.104
International normalized ratio	1.1 ± 0.2	1.4 ± 0.7	0.534
Platelet count	271.9 ± 73.8	282.6 ± 92.0	0.633
Cardiovascular dysfunction	2 (0.41)	0 (0.0)	1
Neurological dysfunction	0 (0.0)	0 (0.0)	1
Respiratory dysfunction	0 (0.0)	0 (0.0)	1
Other vitals and laboratory values
Temperature (˚C)	36.7 ± 0.4	36.6 ± 0.4	0.068
Total bilirubin	1.0 ± 1.4	1.1 ± 1.7	0.852
Direct bilirubin	0.1 ± 0.6	0.5 ± 1.5	0.474
Aspartate aminotransferase	89.5 ± 181.6	64 ± 100.6	0.32
Alanine aminotransferase	94.9 ± 181.8	70.0 ± 96.4	0.32
Alkaline phosphatase	102.3 ± 48.6	111.4 ± 69.6	0.591
Amylase	87.6 ± 235.5	54 ± 5.3	0.112
Lipase	207.6 ± 704.7	477.2 ± 1474.5	0.478

RUQ: Right upper quadrant.

Table 3 Complication rates and types, n (%)

Variable	Same admission cholecystectomy (n = 486)	Delayed cholecystectomy (n = 68)	P value
Total patients with at least 1 complication	90 (18.5)	3 (4.4)	0.004a
Tokyo Grade 1	37 (12.4)	3 (8.3)	0.480
Tokyo Grade 2	46 (26.4)	0 (0.0)	< 0.001a
Tokyo Grade 3	7 (53.8)	0 (0.0)	1
Subtotal cholecystectomy	37 (7.6)	0 (0.0)	0.016a
Death	3 (0.6)	0 (0.0)	1
Hepatobiliary
Common bile duct injury	0 (0.0)	0 (0.0)	–
Bile leak	9 (1.9)	0 (0.0)	0.610
Retained stone	12 (2.5)	0 (0.0)	0.377
Cholangitis	2 (0.4)	0 (0.0)	1
Biliary stenosis	3 (0.6)	0 (0.0)	1
Infection
Wound infection	10 (2.1)	0 (0.0)	0.620
Abscess	2 (0.4)	0 (0.0)	1
Sepsis	1 (0.2)	1 (1.5)	0.231
Clostridium difficile colitis	3 (0.6)	0 (0.0)	1
Intravenous catheter infection	1 (0.2)	0 (0.0)	1
Cardiovascular
Hemorrhage	4 (0.8)	1 (1.5)	0.482
Hemorrhagic shock	1 (0.2)	0 (0.0)	1
Cardiogenic shock	1 (0.2)	0 (0.0)	1
Congestive heart failure exacerbation	3 (0.6)	0 (0.0)	1
Chest pain	1 (0.2)	0 (0.0)	1
Respiratory
Pneumonia	4 (0.8)	1 (1.5)	0.482
Respiratory failure	2 (0.4)	0 (0.0)	1
Pulmonary embolism	1 (0.2)	0 (0.0)	1
Pulmonary edema	1 (0.2)	0 (0.0)	1
Pleural effusion	1 (0.2)	0 (0.0)	1
Gastrointestinal
Pancreatitis	6 (1.2)	0 (0.0)	1
Gastroenteritis	1 (0.2)	0 (0.0)	1
Small bowel injury	1 (0.2)	0 (0.0)	1
Ileus	2 (0.4)	0 (0.0)	1
Hernia
Ventral hernia	1 (0.2)	0 (0.0)	1
Incisional hernia	2 (0.4)	1 (1.5)	0.325
Other
Seizure	1 (0.2)	0 (0.0)	1
Wound dehiscence	2 (0.4)	0 (0.0)	1
Reactive hydrocele	1 (0.2)	0 (0.0)	1

Level of significance was

^aP < 0.05.

Table 4 Hospital length of stay, postoperative readmissions, and charges

Variable	Same admission cholecystectomy, (n = 486), n (%) or mean ± SD	Delayed cholecystectomy, (n = 68), n (%) or mean ± SD	P value
Time to surgical admission (d)		48.3 ± 76.3
Surgical admission length of stay (d)	3.4 ± 5.3	0.4 ± 1.0	< 0.001a
Preoperative (d)	2.2 ± 14.2	0.0 ± 0.2	< 0.001a
Postoperative (d)	1.2 ± 14.8	0.4 ± 0.9	0.204
Readmissions after cholecystectomy
Patients with at least 1 readmission	96 (22.2)	14 (21.2)	0.854
Mean number of readmissions Among those readmitted	1.8 ± 1.5	1.4 ± 0.6	0.074
Total length of stay1 (d)	3.8 ± 5.5	1.6 ± 2.0	< 0.001a
Total hospital charges (× $1000)2	44.5 ± 59.0	35.3 ± 16.7	0.019a

¹Total length of stay includes index admission, elective operative admission for delayed cases, and all postoperative complication-related readmissions.

²Hospital charges for April 2013-August 2018 only. Level of significance was

^aP < 0.05.

Table 5 Logistic regression analysis

Variable	OR		95%CI	P value
Occurrence of any complication - all patients
Same admission cholecystectomy	0.7		0.1-7.7	0.759
Grade 2	2.1		1.2-3.7	0.007a
Grade 3	2.0		0.4-10.2	0.404
Male	1.4		0.8-2.5	0.262
Diabetes	1.2		0.5-3.1	0.722
Hypertension	1.1		0.5-2.4	0.773
Open cholecystectomy	1.1		0.2-5.4	0.863
Insurance status	0.6		0.3-1.2	0.180
Age	1.0		1.0-1.0	0.919
Creatinine	0.9		0.7-1.4	0.780
Occurrence of any complication - Grade 1 patients
Same admission cholecystectomy	0.2		0.0-1.3	0.094
Diabetes	2.5		0.7-9.0	0.157
Insurance status	0.3		0.1-1.0	0.052
Body mass index	1.1		1.0-1.1	0.048a
Occurrence of any complication - Grade 2 patients
Male	1.9	0.7-5.4		0.238
Smoking status	2.1	0.8-5.7		0.156
Open cholecystectomy	2.1	0.1-31.8		0.598
Age	1.0	1.0-1.0		0.975
Body mass index	1.0	1.0-1.1		0.277
Postoperative length of stay	1.4	1.0-2.1		0.056
Aspartate aminotransferase	1.0	1.0-1.0		0.848
Alanine aminotransferase	1.0	1.0-1.0		0.481
Lipase	1.0	1.0-1.0		0.482
Creatinine	2.8	0.3-30.7		0.402
Occurrence of any complication - Grade 2 or 3 patients
Male	2.3	1.0-5.1		0.047a
Open cholecystectomy	1.3	0.2-9.5		0.767
Age	1.0	1.0-1.0		0.326
Body mass index	1.0	1.0-1.0		0.565
Preoperative length of stay	0.8	0.6-1.0		0.061
Creatinine	1.0	0.7-1.4		0.919

Level of significance was

^aP < 0.05. OR: Odds ratio; CI: Confidence interval.

Table 6 Relative risk, attributable risk, and number needed to harm analysis

Variable	Risk	95%CI
All, SA vs delayed
Relative risk	4.2x	1.4 to 12.9a
Attributable risk	14.1%	4.6 to 23.6a
Number needed to harm	8	5.0 to 12.3a
Grade 1, SA vs delayed
Relative risk	1.7x	0.5 to 5.1a
Attributable risk	4.9%	-5.7 to 15.5
Number needed to harm	21	-7.2 to 24.4
Grade 2, SA vs delayed
Relative risk1	–	–
Attributable risk	26.4%	13.2 to 39.7a
Number needed to harm	4	3.0 to 5.0a
Grade 2 or 32, SA vs delayed
Relative risk1	–	–
Attributable risk	28.3%	12.3 to 44.4a
Number needed to harm	4	2.9 to 4.6a

¹Relative risk analysis could not be performed in Grades 2 or 3 due to zero complications in the delayed group.

²Due to a small sample size of the rarer Grade 3 disease, combined analysis of Grades 2 and 3 was performed to represent all moderate and severe cases.

^aStatistically significant. CI: Confidence Interval; SA: Same admission.