Drainage fluid and serum amylase levels accurately predict development of postoperative pancreatic fistula

Table 1 Definitions of postoperative complications after pancreaticoduodenectomy

Complication	Definition
POPF	Drainage fluid amylase activity on or after postoperative day 3 is at least three times the upper limit in normal serum
Ascites	Ultrasound evidence of ascites depth > 5 cm
Hemorrhage	Requires postoperative transfusion of ≥ 2 U isogenic red blood cells
Biliary fistula	Abdominal drainage produces bilious fluid at 50 mL/d after surgery
DGE	Indwelling stomach tube for > 10 d

POPF: Postoperative pancreatic fistula; DGE: Delayed gastric emptying.

Table 2 Summary of postoperative complications

Complication	Cases, n = 30	Incidence, %
POPF	28	33.7
Type A	8	28
Type B	16	58
Type C	4	14
Ascites	4	10
Hemorrhage	7	17.5
Biliary leakage	1	2.5
DGE	1	2.5
Postoperative acute pancreatitis	1	2.5

POPF: Postoperative pancreatic fistula; DGE: Delayed gastric emptying.

Table 3 General risk factors for pancreatic leakage

Variable	POPF (n = 14)	Non-POPF (n = 26)	t/z/χ2	P value
Age in yr	54.18 ± 6.945	54.04 ± 10.447	0.065	0.948
Sex
Male	20 (71.4)	32 (58.2)	1.391	0.3371
Female	8 (28.6)	23 (41.8)
Blood loss in mL	300 (200, 575)	200 (200, 600)	-1.266	0.205
Pancreatic duct diameter in mm
> 3	11 (39.3)	33 (60.0)	3.196	0.1041
< 3	17 (60.7)	22 (40.0)
Preoperative low plasma protein
Yes	7 (25.0)	12 (21.8)	0.106	0.7861
No	21 (75.0)	43 (78.2)
Preoperative relief of jaundice
Yes	4 (14.3)	4 (7.3)	1.048	0.4331
No	24(85.7)	51 (92.7)
Preoperative jaundice
Yes	18 (64.3)	34 (61.8)	0.048	1.000
No	10 (35.7)	21 (38.2)
Surgical type
External drainage of PD	12 (42.9)	27 (49.1)	0.289	0.6471
Internal drainage of PD	16 (57.1)	28 (50.9)
Diabetes
Yes	2 (7.1)	0 (0.0)	4.026	0.1111
No	26 (92.9)	55 (100.0)
Duration of surgery in min	267.5 (240.0, 327.5)	280.0 (235.0, 335.0)	-0.082	0.935
Hospitalization period in days	15.00 (13.00, 18.00)	21.50 (18.00, 27.75)	-4.385	< 0.001
Drainage fluid amylase level on POD1 in U/L	6017.5 (2494.5, 11752.5)	890.0 (350.0, 1500.0)	-5.110	< 0.001
Serum amylase level in U/L
POD1	379.5 (157.5, 627.5)	124.0 (80.0, 165.0)	-4.091	< 0.001
POD4	30.0 (30.0, 50.0)	61.5 (45.5, 150.0)	-4.435	< 0.001
Serum albumin
POD1	29.5 (25.3, 34.3)	30.7 (26.6, 33.0)	-0.125	0.900
POD3	30.1 (25.7, 34.6)	30.4 (27.1, 33.2)	-0.111	0.912
POD5	30.8 (27.8, 34.4)	31.4 (28.4, 36.9)	-0.718	0.473
Choline
POD1	4957 (4022, 4957)	5242 (4048, 6715)	-0.876	0.381
POD3	3481 (2626, 4518)	4056 (3345, 5020)	-1.425	0.154
POD5	3268 (2696, 4537)	4024 (3248, 5069)	-1.580	0.114
WBC count
POD1	14.73 (10.84, 18.75)	15.49 (12.42, 18.41)	-0.751	0.452
POD3	14.90 (11.74, 18.64)	13.54 (10.34, 16.58)	-1.112	0.266
POD5	11.99 (9.65, 15.56)	11.24 (9.17, 14.79)	-0.510	0.610
Pathology examination result			2.445	0.485
Cholangiocarcinoma	12 (42.9)	29 (52.7)
Pancreatic carcinoma	3 (10.7)	8 (14.5)
Ampullary carcinoma	3 (10.7)	7 (12.7)
Other	10 (35.7)	11 (20.0)

Data are presented as n (%).

¹Fisher’s exact test. POPF: Postoperative pancreatic fistula; PD: Pancreaticoduodenectomy; WBC: White blood cell; POD: Postoperative day.

Table 4 Results of univariate analysis showing risk factors for postoperative pancreatic fistula

Factor	β	SE	Waldχ2	OR (95%CI)	P value
Age in yr	0.023	0.037	0.397	1.024 (0.952-1.101)	0.529
Sex, female/male	-0.586	0.500	1.375	0.557 (0.209-1.482)	0.241
Blood loss in mL	0.000	0.001	0.257	1.000 (0.999-1.001)	0.612
Pancreatic duct diameter,	-0.841	0.475	3.135	0.431 (0.170-1.094)	0.077
> 3 mm/< 3 mm
Preoperative low plasma protein, yes/no	0.178	0.545	0.106	1.194 (0.410-3.476)	0.744
Preoperative relief of jaundice, yes/no	0.754	0.749	1.012	2.125 (0.489-9.227)	0.314
Preoperative jaundice, yes/no	0.106	0.482	0.048	1.112 (0.432-2.861)	0.826
Internal or External drainage of PD	0.251	0.468	0.289	1.286 (0.514-3.214)	0.591
Diabetes, yes/no	21.952	28420.722	0.000	3.417E9 (0.000)	0.999
Pathology examination result, ampullary carcinoma/pancreatic carcinoma/cholangiocarcinoma	0.241	0.182	1.757	1.273 (0.891-1.819)	0.185
Duration of surgery in min	0.000	0.003	0.008	1.000 (0.995-1.005)	0.928
Drainage fluid amylase level, POD1 > 5000 U/L	0.000	0.000	10.293	1.000 (1.000--1.000)	0.001
Serum amylase level
POD1 > 140 U/L	0.004	0.001	9.982	1.004 (1.001-1.006)	0.002
POD4 > 140 U/L	0.013	0.005	7.752	1.013 (1.004-1.022)	0.005
Serum albumin
POD1	0.000	0.045	0.000	1.000 (0.916, 1.092)	0.994
POD3	-0.006	0.044	0.020	0.994 (0.911, 1.084)	0.887
POD5	-0.023	0.044	0.277	0.977 (0.897, 1.064)	0.599
Choline
POD1	-0.016	0.041	0.149	0.984 (0.908, 1.067)	0.700
POD3	0.033	0.046	0.521	1.034 (0.945, 1.131)	0.470
POD5	0.007	0.053	0.016	1.007 (0.908, 1.117)	0.898
WBC count
POD1	0.000	0.000	1.153	1.000 (1.000, 1.000)	0.283
POD3	0.000	0.000	1.298	1.000 (0.999, 1.000)	0.255
POD5	0.000	0.000	2.026	1.000 (0.999, 1.000)	0.155

POPF: Postoperative pancreatic fistula; PD: Pancreaticoduodenectomy; WBC: White blood cell; POD: Postoperative day.

Table 5 Results of multivariate logistic regression analysis showing risk factors for postoperative pancreatic fistula

Predictor	β	SE	Waldχ2	OR (95%CI)	P value
Amylase level, POD1 > 5000 U/L	0.000	0.000	6.728	1.000 (1.000--1.000)	0.009
Serum amylase, level POD1 > 140 U/L	0.001	0.002	0.243	1.001 (0.998-1.004)	0.622
Serum amylase level, POD4 > 140 U/L	0.009	0.004	3.826	1.009 (1.000-1.017)	0.050

POPF: Postoperative pancreatic fistula; POD: Postoperative day.