Factors associated with time to laparoscopic cholecystectomy for acute cholecystitis

Table 1 Patient characteristics n (%)

	Medical service n = 12	Surgical service n = 58	Total n = 70	P value
Mean age (range)	66 (38-89)	52 (20-83)	53 (20-89)	< 0.05
Age > 75 yr	5 (42)	7 (12)	12 (17)
Sex
Male	5 (42)	25 (43)	30 (43)
Female	7 (58)	33 (57)	40 (57)
Co-morbidities				< 0.05
None	4 (33)	44 (76)	48 (69)
Minor	4 (33)	7 (12)	11 (16)
Abnormal ECG	8 (67)	16 (28)	24 (34)
Rhythm other than sinus	5 (42)	2 (3)	7 (10)
Poor functional capacity	5 (42)	4 (69)	9 (13)
History of stroke	0 (0)	3 (5)	3 (4)
Intermediate	4 (33)	5 (9)	9 (13)
Prior MI	3 (25)	3 (5)	6 (8)
Compensated or prior CHF	2 (17)	0 (0)	2 (3)
Diabetes mellitus	2 (17)	5 (9)	7 (10)
Major	0 (0)	2 (3)	2 (3)
Liver cirrhosis	0 (0)	2 (3)	2 (3)
Physical examinaition
WBC > 10.2	7 (58)	29 (50)	36 (51)
Murphy’s sign	4 (33)	15 (26)	19 (27)
Temp > 37.8°C	2 (17)	14 (24)	16 (23)

ECG: Electrocardiogram; MI: Myocardial infarction; CHF: Compensated heart failure.

Table 2 Hospital course n (%)

	Medical service n =12	Surgical service n = 58	Total n = 70	P value
Tests done
Ultrasound	9 (75)	44 (76)	53 (76)
CT scan	9 (75)	24 (41)	33 (47)	< 0.05
HIDA scan	4 (33)	12 (21)	16 (23)
MRI/MRCP	1 (8)	1 (2)	2 (3)
ERCP	4 (33)	3 (5)	7 (10)
Time to surgery
Mean time to operation, h (SD)	82.7 (55.1)	30.4 (34.9)	39.3 (43.4)	< 0.01
Operation within 3 d	7 (58)	54 (93)	61 (87)	< 0.01
Operation within 1 d	2 (17)	34 (59)	36 (51)	< 0.01
Length of stay
Mean, D (SD)	8.1 (5.2)	4.3 (3.4)	5.0 (3.9)	< 0.01
3 d or less	2 (17)	30 (52)	32 (46)	< 0.05
6 d or more	8 (67)	11 (19)	19 (27)	< 0.01
Conversion to open	1 (8)	3 (5)	4 (6)
post-operative complications	7 (58)	7 (12)	14 (23)	< 0.01
Mild	4 (33)	5 (9)	9 (13)
Moderate	2 (17)	3 (5)	5 (7)
Severe	1 (8)	1 (2)	2 (3)

HIDA: Nuclear Hepatobiliary scan; MRI: Magnetic resonance imaging ERCP: Endoscopic retrograde cholangiopancreatography; MRCP: Magnetic resonance cholangiopancreatography.

Table 3 Hierarchical linear models for time to surgery

Model	Estimate mean (h)	Standard error	95% CI	P value4
ERCP
Unadjusted				< 0.01
Yes	149	17	115.0-183.0
No	32.7	4.2	24.3-41.1
Adjusted for patient demographics1				< 0.01
Yes	141.8	17.1	107.7-175.8
No	33.1	4.1	24.9-41.4
Adjusted for demographics and co-morbidity				< 0.01
Yes	143.5	16.2	111.1-175.8
No	33.0	3.9	25.2-40.8
Adjusted for demographics, co-morbidity and physical signs2				< 0.01
Yes	144.7	16.3	112.0-177.4
No	33.0	3.9	25.1-40.8
Adjusted for demographics, co-morbidity, physical signs2 and imaging studies3				< 0.01
Yes	134.1	16.2	101.7-166.7
No	33.6	3.8	26.0-41.2
Admission service
Unadjusted				< 0.01
Surgery	30.4	5.1	20.2-40.6
Medicine	82. 7	11.2	60.3-105.1
Adjusted for patient demographics				< 0.01
Surgery	31.4	5.1	21.3-41.5
Medicine	77.6	11.4	54.9-100.4
Adjusted for demographics and co-morbidity				< 0.01
Surgery	32.1	5.0	22.0-42.1
Medicine	74.6	11.5	51.7-97.5
Adjusted for demographics, co-morbidity and physical signs				< 0.01
Surgery	32.2	5.1	21.9-45.5
Medicine	73.8	11.8	50.1-97.4
Adjusted for demographics, co-morbidity, physical signs and imaging studies				< 0.05
Surgery	34.2	5	24.2-44.1
Medicine	64.4	11.9	40.7-88.2
Adjusted for demographics, co-morbidity, physical signs, imaging studies and ERCP
Surgery	35.9	4.5	26.8-45.0
Medicine	55.9	11	33.9-77.9
Pre-operative diagnostic tests3
Unadjusted				< 0.01
One	26.9	6.4	14.2-39.6
Two	54.3	8.2	38.0-70.6
Three	56.7	23.5	9.7-103.7
Four	125	40.8	43.6-206.4
Adjusted for patient demographics				< 0.01
One	29.0	6.2	16.6-41.4
Two	51.5	8.0	35.6-67.4
Three	48.11	23.6	1.0-95.2
Four	133.2	39.7	53.8-212.5
Adjusted for demographics and co-morbidity				< 0.01
One	27.8	6.0	15.8-39.7
Two	53.6	7.7	38.3-68.9
Three	46.6	22.6	1.4-91.7
Four	135.5	38.1	59.4-211.6
Adjusted for demographics, co-morbidity and physical signs				< 0.01
One	26.9	6.1	14.7-39.1
Two	55.1	7.9	39.3-70.9
Three	48.1	23.4	1.4-94.8
Four	129.3	40.2	48.8-209.8

¹Age and sex;

²Murphy's sign, leukocytosis, and fever;

³Imaging studies include ultrasound, CT scan, MRCP, and HIDA scan;

⁴Measure the differences in means (for more than two means, P < 0.05 indicates that at least one pair of means is statistically significantly different).

Table 4 Hierarchical linear models for effect of pre-operative imaging studies on time to surgery

Model	Estimate mean (h)	Standard error	95% CI	P value4
Unadjusted				< 0.01
All studies done	125.0	36.8	51.4-198.6
US only	23.6	6.6	10.4-36.8
US and HIDA	25.2	15.0	0.0-55.2
CT only	37.0	11.7	13.7-60.3
CT and MRCP	192.0	36.8	118.4-265.6
CT and HIDA	59.2	15.0	29.1-89.2
CT and US	54.9	10.6	33.7-76.2
US, CT and HIDA	56.7	21.3	14.2-99.2
Adjusted for patient demographics1				< 0.01
All studies done	128.3	36.6	55.1-201.6
US only	24.7	6.6	11.4-38.0
US and HIDA	26.2	14.9	0.0-56.0
CT only	38.3	11.5	15.3-61.3
CT and MRCP	179.5	37.5	104.5-254.4
CT and HIDA	58.2	15.0	28.2-88.3
CT and US	52.4	10.6	31.3-73.5
US, CT and HIDA	53.9	21.8	10.3-97.4
Adjusted for demographics and co-morbidity				< 0.01
All studies done	130.6	35.4	59.9-201.4
US only	23.1	6.5	10.2-36.0
US and HIDA	29.7	14.4	0.9-58.6
CT only	39.4	11.1	17.1-61.6
CT and MRCP	169.6	36.4	96.8-242.5
CT and HIDA	58.0	14.5	29.0-87.0
CT and US	55.2	10.3	34.6-75.7
US, CT and HIDA	52.2	21.0	10.1-94.3
Adjusted for demographics, co-morbidity and physical signs2				< 0.01
All studies done	121.0	36.4	48.1-193.2
US only	20.4	6.5	7.5-33.3
US and HIDA	29.7	14.3	1.2-58.3
CT only	41.3	11.1	19.1-63.6
CT and MRCP	186.3	36.5	113.1-359.5
CT and HIDA	60.3	15.2	29.9-90.7
CT and US	58.4	10.6	37.0-79.7
US, CT and HIDA	53.5	21.3	10.9-96.0
Adjusted for demographics, co-morbidity, physical signs and admission service3				< 0.01
All studies done	94.7	36.4	21.8-167.5
US only	23.3	6.3	10.7-35.9
US and HIDA	33.9	13.7	6.4-61.4
CT only	42.3	10.6	21.0-63.7
CT and MRCP	195.4	35.1	125.1-256.8
CT and HIDA	55.5	14.64	26.2-84.9
CT and US	52.7	10.42	31.8-73.6
US, CT and HIDA	49.9	20.36	9.1-90.7

US: Ultrasound; HIDA: Nuclear Hepatobiliary Scan; MRCP: Magnetic resonance cholangiopancreatography.

¹Age and sex;

²Murphy's sign, leukocytosis, and fever;

³Surgical and medical services;

⁴Measure the differences in means (for more than two means, P < 0.05 indicates that at least one pair of means is statistically significantly different).

Table 5 Hierarchical linear models for association between time to surgery and risk of complication

Model	Odds ratio	95% CI	P value
Unadjusted (h)			> 0.01
< 24	0.03	0.004-0.24
24-48	0.3	0.05-1.52	> 0.05
48-72	0.2	0.02-1.74	> 0.05
> 72 (reference)	1		> 0.05
Adjusted for patients demographics (h)1
< 24	0.05	0.003-0.65
24-48	0.38	0.04-4.03
48-72	0.27	0.01-5.01
> 72	1
Adjusted for demographics and co-morbidity (h)
< 24	0.05	0.003-0.74
24-48	0.44	0.04-5.00
48-72	0.26	0.01-4.91
> 72 (reference)
Adjusted for demographics, co-morbidity and physical signs (h)2
< 24	0.04	0.003-0.45
24-48	0.33	0.03-3.49
48-72	0.25	0.01-5.06
> 72	1
Adjusted for demographics, co-morbidity, physical signs and imaging studies (h)3
< 24	0.08	0.004-1.61
24-48	0.66	0.04-12.2
48-72	0.41	0.01-13.5
> 72	1

¹Age and sex;

²Murphy’s sign, leukocytosis, and fever;

³Imaging studies included abdominal ultrasound, CT scan, MRCP, and HIDA scan. Abbreviations as in Table 4.