Outcome of a session of extracorporeal shock wave lithotripsy before endoscopic retrograde cholangiopancreatography for problematic and large common bile duct stones

Table 1 Baseline characteristics of patients in the extracorporeal shock wave lithotripsy + endoscopic retrograde cholangiopancreatography group and the endoscopic retrograde cholangiopancreatography-only group n (%)

Demographic characteristic	ESWL + ERCP (n = 124)	ERCP only (n = 107)	P value
Age (yr)	71.2 ± 4.6	68.4 ± 6.1	0.647
Male	63 (50.8)	56 (52.3)	0.318
Prothrombin time/INR	1.14 ± 0.22	1.19 ± 0.34	0.382
Periampullary diverticulum	54 (43.5)	48 (44.9)	0.263
Pre-cut sphincterotomy	65 (52.4)	60 (56.1)	0.187
Calculi characteristic
Single	83	72
Multiple	41 (33.1)	35 (32.7)	0.371
Stone size	18.3 ± 2.5	16.6 ± 3.8	0.084
1.5-3.0 cm	104	93
> 3.0 cm	15 (12.1)	10 (9.3)	0.195

ESWL: Extracorporeal shock wave lithotripsy; ERCP: Endoscopic retrograde cholangiopancreatography; INR: International normalized ratio.

Table 2 Endoscopic stone removal observed after endoscopic retrograde cholangiopancreatography n(%)

Attempt	ESWL + ERCP (n = 124)	ERCP only (n = 107)	P value
First	92/124 (74.2)	76/107 (71.0)	0.135
Second	27/32 (84.4)	16/31 (51.6)	0.018a
Total	119/124 (96.0)	92/107 (86.0)	0.029b
Number (rate) of mechanical lithotripsy	30/150 (20)	41/138 (30)	0.025c
Mean duration of ERCP procedure (min)	43 ± 21	59 ± 28	0.034d

The CBD stone clearance rate observed after the second session of ESWL + ERCP procedure and the total clearance rate differed significantly (

^aP < 0.05,

^bP < 0.05). The use of mechanical lithotripsy and ERCP procedure time also differed significantly between the two groups (

^cP < 0.05,

^dP < 0.05). ESWL: Extracorporeal shock wave lithotripsy; ERCP: Endoscopic retrograde cholangiopancreatography; CBD: Common bile duct.

Table 3 Extraction methods and success rates after endoscopic retrograde cholangiopancreatography

Extraction method	Success rate
	ESWL + ERCP (n = 124)	ERCP only (n = 107)	P value
Balloon or Dormia basket	96/99	65/71	0.251
Mechanical lithotripsy	23/25	27/36	0.041a
Stone size
1.5-3.0 cm	102/104	90/93	0.473
≥ 3.0 cm	12/15	4/10	0.016b
Total	119/124 (96.0%)	92/107 (86.0%)	0.029c

The use of mechanical lithotripsy differed significantly different between the two groups (

^aP < 0.05). The rate of successful clearance of stones sized 1.5-3.0 cm was similar in the two groups, whereas the clearance rate in patients with stones ≥ 3.0 cm and total stone clearance were both greater in the ESWL + ERCP group (

^bP < 0.05,

^cP < 0.05). ESWL: Extracorporeal shock wave lithotripsy; ERCP: Endoscopic retrograde cholangiopancreatography.

Table 4 Complications in the extracorporeal shock wave lithotripsy + endoscopic retrograde cholangiopancreatography group and the endoscopic retrograde cholangiopancreatography-only group n(%)

Complication	ESWL + ERCP	ERCP only	P value
Post-ERCP	10/150 (6.7)	9/138 (6.5)	0.673
Pancreatitis (mild)	5/150 (3.3)	5/138 (3.6)	0.357
Cholangitis (mild)	3/150 (2.0)	3/138 (2.2)	0.218
Hemobilia (mild)	2/150 (1.9)	1/138 (0.7)	0.074
Bowel perforation	0	0
Procedure-related mortality	0	0
Post-ESWL	11/156 (7.0)
Purpuric spots	5/156 (3.2)
Skin ecchymosis	6/156 (3.8)
Splenic rupture	0
Lung trauma	0
Necrotizing pancreatitis	0
Procedure-related mortality	0

ESWL: Extracorporeal shock wave lithotripsy; ERCP: Endoscopic retrograde cholangiopancreatography.