Intraoperative and Postoperative Complications of Laparoscopic Pyeloplasty: A Single Surgical Team Experience with 236 Cases

Abstract

Purpose:

To describe and analyze a single surgical team's experience with intraoperative and postoperative complications arising from the Anderson-Hynes transperitoneal laparoscopic pyeloplasty (LP) procedure in the treatment of patients with ureteropelvic junction obstruction (UPJO).

Patients and Methods:

There were 236 consecutive patients who underwent transperitoneal LP over a period of 8 years (2004–2012). These patients' records were retrospectively analyzed for intraoperative and postoperative complications. Of the 236 patients, 111 (47.0%) were males and 125 (53%) were females. In 226 patients, surgical indication was primary UPJO, and in 10 patients, recurrent obstruction. Two hundred and eleven patients (89.4%) were symptomatic.

Results:

Mean operative time was 96.5 minutes (range 45–360 min). The mean blood loss was 20 mL (range 5–500 mL), and no blood transfusions were necessary. The overall success rate was 97% (229 patients) with a mean follow-up of 38 months (range 6–84 mos). In 86 of the 94 patients who presented with a crossing vessel (91.5%), the anomalous crossing vessel was transposed to the ureteropelvic junction (UPJ) dorsally because of evident obstruction. The mean postoperative hospital stay was 4.2 days (range 3–14 days). All 211 preoperative symptomatic patients reported a complete resolution of symptoms after the procedure. Intraoperative incidents occurred in nine (3.8%) patients, while postoperative complications occurred in 32 (13.5%) patients.

Conclusions:

Our retrospective analysis confirms that LP is an efficacious and safe procedure resulting in a reported success rate of 97% and a concomitant low level of intraoperative (3.8%) and postoperative complications (13.6%). Major complications necessitating active management occur in a low percentage of cases (5.9% of patients). The most frequent and severe intraoperative complications are related to the Double-J stent insertion. The most common postoperative complication is urine leakage.

Introduction

U reteropelvic junction obstruction (UPJO) is a frequent urologic condition with excellent surgical treatment outcomes since Anderson–Hynes first described this dismembered pyeloplasty technique more than 50 years ago.¹ The Anderson–Hynes procedure continues to be the gold standard with an overall success rate of 90%.² First described in 1993 by Schuessler and colleagues, laparoscopic pyeloplasty (LP) has been adopted as a feasible and reliable treatment for patients with UPJO over the last two decades with a success rate equivalent to that of the open procedure and is associated with minimal morbidity and a significant reduction in hospital care costs.³

The complications of LP at a treatment center are associated with surgeon learning curves and previous experience and are contingent on the anatomic features of each patient. During the last few years, the intraoperative and postoperative complications of this procedure have been described according to standardized reporting systems, such as the Satava and the Clavien-Dindo.^4,5

The aim of this study is the description and analysis of a single surgical team's experience with complications arising from the Anderson-Hynes transperitoneal LP procedure in the treatment of patients with UPJO.

Patients and Methods

Patients

Two hundred and thirty-six patients (ages 8–73 years) who underwent LP between 2004 and 2012 were included in the analysis. Of the 236 patients, 111 (47.0%) were males and 125 (53%) were females. In 226 patients, the surgical indication was primary UPJO, and in 10 patients, recurrent obstruction. In 112 (47.5%) patients, UPJO was on the left side, while in 124 (52.5%) patients, UPJO was on the right side. Two hundred and eleven (89.4%) patients reported at least one episode of flank pain and/or fever. All patients were evaluated preoperatively with renal ultrasonography (US) and intravenous urography (IVU) with a high-volume contrast medium or CT. All patients presented with severe hydronephrosis with a dilated extrarenal renal pelvis, and in 20 patients, stones were detected in the renal pelvis. In eight patients, UPJO was associated with severe renal ptosis.

All procedures described here were performed by a single experienced laparoscopic team. In all cases, pyeloplasty using the Anderson-Hynes technique was performed. A transperitoneal approach was used in all cases. Ventrally crossing vessels were found in 94 (40%) patients. Two cases consisted of a horseshoe kidney on the right side. A retrocaval ureter was incidentally diagnosed in one (0.4%) patient, while in five (2.1%) patients, a large parapyelic cyst was associated with UPJO. Study population characteristics are reported in Table 1.

Table 1.

Laparoscopic Pyeloplasty: Analyses of 236 Cases

Number	236
Average age	32 (8–73)
Primary UPJO	226 (95.8%)
Recurring UPJO	10 (4.2%)
Males	111 (47%)
Females	125 (53%)
Symptomatic patients	211 (89.4%)
Right side	124 (52.5%)
Left side	112 (47.5%)
Anderson-Hynes technique	236 (100%)
Parapyelic cyst	5 (2.1%)
Renal ptosis	8 (3.4%)
Crossing vessel	94 (40.0%)
Horseshoe kidney	2 (0.9%)
Pelvic stone	20 (8.5%)
Retrocaval ureter	1 (0.4%)

UPJO=ureteropelvic junction obstruction.

Treatment success was defined by imaging (partial or complete resolution of hydronephrosis on US, IVU, or CT), functional assessment (improvement on renal scan), and on the basis of clinical findings (resolution of pain). Renal US and IVU were performed 6, 12, and 18 months postoperatively, and a yearly follow-up with either IVU or renal US thereafter was indicated.

Intraoperative incidents were analyzed using the Satava classification, and postoperative complications were analyzed using the Clavien-Dindo classification.

A single tail t test at 95% confidence interval of the difference and chi-square one degree of freedom were used to compare the results of patients who presented with primary or secondary UPJO.

Surgical procedure

The patients were placed in the lateral decubitus position after placement of the ureteral catheter in retrograde fashion, and retrograde ureterography was performed. Initial transperitoneal access was performed through an open Hasson approach using an Hasson cannula. A 0-degree telescopic and two multidisposal metal trocars (1×10–11 mm, 1×5 mm) were used. Dissection was performed by using monopolar scissors and bipolar forceps. The proximal ureter was spatulated with a lateral incision after resection and removal of the stenotic UPJ. When we encountered a ventrally crossing vessel, we opted to transpose dorsally to the UPJ only in cases of real obstruction. The anastomosis was performed using a running 5-0 absorbable suture. A Double-J stent was routinely inserted in retrograde fashion, but in male patients, this step was completed at the end of the laparoscopic intervention under fluoroscopic and cystoscopic control.

Results

Table 2 summarizes the results of our series of surgical procedures. Mean operative time was 92 (range 45–360) and 200 minutes (range 150–240) in patients with primary and secondary UPJO, respectively. The mean blood loss was 20 mL (range 5–500 mL) and 40 mL (range 20–100 mL) in patients with primary and secondary UPJO, respectively. No blood transfusions were necessary.

Table 2.

Results of Laparoscopic Pyeloplasty

Parameters	Values
Operative time	96.5 min (45–360)
Blood loss	20 mL (5–500)
Blood transfusion	0
Overall success rate	229/236 patients (97%)
Transposing of crossing vessel	86/94 (91.5%)
Postoperative hospital stay	4.2 days (3–14)
Significative reduction in preoperative hydronephrosis	223/236 patients (94.5%)
Intraoperative incidents	9/236 patients (3.6%)
Postoperative complications	32/236 patients (13.5%)

All operations were performed laparoscopically without conversion to open surgery. The success rate was 97% (219 patients) and 100% (10 patients) in primary and secondary UPJO patients, respectively, with an overall success rate of 97%. Mean follow-up was 38 months (range 6–84 mos). In 86 of the 94 patients who presented with a crossing vessel (91.5%), the anomalous crossing vessel was transposed dorsally to the UPJ because of evident obstruction. No intraoperative or postoperative complications were detected in patients when we opted not to transpose the anomalous crossing vessel, and all such procedures resulted in success.

The Foley catheter was removed postoperatively on day 2 or 3. In only three patients was the Foley catheter left in place for a longer period because of urine leakage through the suction drain. The closed suction drain placed in the peritoneal cavity was removed if the drainage output did not increase and was less than 10 mL within 24 hours after Foley catheter removal. The Double-J stent was removed 4 weeks postoperatively with the exception of a single patient in whom infectious urinoma developed, in which case the ureteral stent was replaced with a larger one postoperatively on day 9 and removed 5 weeks postoperatively. The mean postoperative hospital stay was 4.1 days (range 3–14 days) and 6 days (range 4–7) in primary and secondary UPJO patients, respectively. All 211 patients with preoperative symptoms reported a complete resolution of symptoms after the procedure.

The radiologic follow-up showed a normal ureteropelvic junction (UPJ) and a significant reduction in preoperative hydronephrosis in all patients with the exception of 13 (5.5%) for whom persistence of a UPJO with a degree of hydronephrosis with no improvement compared with their preoperative stage was detected at the first postoperative follow-up visit at month 6. All patientss were initially conservatively treated by retrograde insertion of a Double-J stent left in place for 3 months, and this treatment resulted in a definitive resolution of persistent UPJO in six patients. The remaining seven patients underwent a successful second laparoscopic dismembered pyeloplasty. All patients who presented with concomitant renal stones were stone free at consecutive follow-up visits.

Intraoperative incidents occurred in nine (3.8%) patients and are detailed in Table 3. Postoperative complications occurred in 32 (13.5%) patients and are detailed in Table 4. The most frequent intraoperative incident was the misplacement of the Double-J stent with the distal tip at the level of the distal ureter while the most severe intraoperative complication (grade III) was because in one case, the ureteral stent got entangled with the running suture of the pyeloplasty. The most frequent postoperative complication was urine leakage (2.5%).

Table 3.

Intraoperative Incidents According to the Satava System

Complication	Grade	n (%)	Management
Kidney capsular lesion with a needle or grasper	1	2 (0.8%)	Conservative
Lesion of the renal pelvis	2	1 (0.4%)	Laparoscopic repair (through a suture)
Migration of ureteral stent	2	4 (1.8%)	Endoscopic retrieval
Injury of parapyelic vessel	2	1 (0.4%)	Laparoscopic repair (through clamping of the vessel)
Stent pierced by suture of pyeloplasty	3	1 (0.4%)	Laparoscopic revision and re-pyeloplasty (on postoperative day 9)
Overall		9 (3.8%)

Table 4.

Postoperative Complications According to the Clavien-Dindo System

Early complication (<1 month postoperatively)	Grade	n (%)	Management
Subcutaneous emphysema	I	5 (2.1%)	Conservative
Transient hematuria	I	5 (2.1%)	Conservative
Temporary Ileus	II	1 (0.4%)	Conservative
Prolonged urine drainage	II	2 (0.9%)	Prolonged urethral catheterization and forced diuresis
Urinary tract infection	II	5 (2.1%)	Prolonged antibiotics
Urine leakage	IIIa	6 (2.5%)	Placement of a percutaneous nephrostomy in 6 patients and re-placement of the ureteral stent in 1 patient
Infectious urinoma	IIIb	1 (0.4%)	Open revision (on postoperative day 9)
Late complication (>1 month postoperatively)
Recurrent UPJO	IIIb	7 (3%)	Laparoscopic repyeloplasty
Overall		32 (13.5%)

UPJO = ureteropelvic junction obstruction.

Table 5 summarizes the incidence of both intraoperative and postoperative complications according to the different phases of the learning curve.

Table 5.

Intra- and Postoperative Complications According to the Satava and Clavien-Dindo Systems During the Learning Curve

Intraoperative complication	Grade	Pts 1–25, n (%)	Pts 26–50, n (%)	Pts 51–75, n (%)	Pts 76–150, n (%)	Total, n (%)
Kidney capsular lesion with a needle or grasper	1	0	1/25 (4%)	0	1/25 (1.3%)	2/236 (0.8%)
Lesion of the renal pelvis	2	0	1/25 (4%)	0	0	1/236 (0.4%)
Migration of ureteral stent	2	0	1/25 (4%)	2/25 (8%)	1/75 (1.3%)	4/236 (1.8%)
Injury of parapyelic vessel	2	1/25 (4%)	0	0	0	1/236 (0.4%)
Stent pierced by suture of pyeloplasty	3	0	0	1/25 (4%)	0	1/236 (0.4%)
Overall		1/25 (4%)	3/25 (12%)	3/25 (12%)	2/75 (2.6%)	9/236 (3.8%)

Discussion

Our retrospective analysis on a very large series of transperitoneal LP and reporting complications in accordance with major classification criteria confirms that transperitoneal pyeloplasty is an efficacious and safe procedure resulting in a reported success rate of 97% and a concomitant low level of intraoperative (3.8%) and postoperative complications (13.6%).

Surgical treatment for patients with UPJO includes various procedural options such as different types of open pyeloplasty, antegrade or retrograde endopyelotomy, and laparoscopic and robot-assisted pyeloplasty.^6
–8 The advantages of minimally invasive procedures over traditional open pyeloplasty include a shortened hospital stay and significant morbidity reduction^9
–11 when compared with the conventional open procedure that requires a large incision, associated pain, and risk of nerve injury.¹² A comparison of antegrade and retrograde endopyelotomy reported no significant difference in success rates between these two procedures.¹³ The laparoscopic approach guarantees high success rates and, in addition, offers the advantage of a minimally invasive procedure in terms of low morbidity, shortened hospital stay, and rapid postoperative recovery.

LP can be performed using either a transperitoneal or, alternatively, a retroperitoneal approach. The transperitoneal technique offers the advantages of a larger working space and promptly identifiable anatomic landmarks, while the retroperitoneoscopic technique has the advantage of direct access to the urinary tract and the avoidance of manipulation and contact with the intraperitoneal organs.⁴

Rassweiler and associates¹⁴ were the first to report on intraoperative and postoperative complications using the Satava and modified Clavien classification in a series of 189 patients of whom only 66 underwent the Anderson-Hynes procedure.

To our knowledge, this present study reports detailed intraoperative and postoperative complications classified in accordance with international criteria on the largest series of transperitoneal pyeloplasty interventions using the Anderson-Hynes technique and compares the data collected with that of previously published series (Table 6).

Table 6.

Intraoperative Complications: Comparison with Other Authors

	Present series N=236	Rassweiler et al. (2008) N=189	Shoma et al. (2007) N=40	Moon et al. (2006) N=170	Inagaki et al. (2005) N=147	Jarrett et al. (2002) N=100	Soulie et al. (2001) N=55
According to the Satava system
Grade 1	2 (0.8%)	1 (0.6%)	1 (2,5%)	0	0	0	0
Kidney capsular lesion with a needle or grasper	2	-	-	-	-	-	-
Lost needle	-	1	-	-	-	-	-
Hypercapnia	-	-	1	-	-	-	-
Grade 2	6 (2.6%)	3 (1.6%)	3 (7,5%)	2 (1.2%)	2 (1.4%)	1 (1%)	3 (5.6%)
Lesion of the renal pelvis	1	-	-	-	-	-	-
Migration of Double-J stent	4	1	1	1	-	-	-
Injury of parapyelic vessel/lower pole artery	1	1	1	-	-	1	-
Cutting of the Double-J stent	-	-	1	-	2	-	-
Inability to dissect UPJ	-	-	-	-	-	-	3
Inability to approximate ureter and pelvis	-	1	-	1	-	-	-
Grade 3	1 (0.4%)	0	0	2 (1.2%)	1 (0.7%)	1 (1%)	0
Stent pierced by suture of pyeloplasty	1	-	-	-	-	-	-
Colonic injury	-	-	-	1	1	1	-
Port site bleeding	-	-	-	1	-	-	-
TOTAL	9 (3.8%)	4 (2.2%)	4 (10%)	4 (2.4%)	3 (2.1%)	2 (2%)	3 (5.6%)
According to the Clavien-Dindo system
Grade 1	10 (4.2%)	3 (1.6%)	2 (5%)	1 (0.6%)	1 (0.7%)	0	0
Subcutaneous emphysema	5	1	1	-	-	-	-
Transient hematuria	5	2	1	1	1	-	-
Temporary neuropathy	-	-	-	-	-	-	-
Grade 2	8 (3.4%)	6 (3.2%)	3 (7.5%)	5 (2.9%)	6 (4.1%)	6 (6%)	4 (7.2%)
Temporary Ileus	1	-	-	-	1	1	-
Prolonged urine drainage	2	1	2	1	1	-	-
Urinary tract infection	5	2	-	1	-	-	-
Blood transfusion	-	1	-	-	2	3	-
Port site infection	-	1	-	1	-	-	3
Elevated fever	-	1	1	2	-	-	1
Pneumonia	-	-	-	-	1	1	-
Thrombophlebitis	-	-	-	-	1	1	-
Grade 3	14 (5.9%)	20 (10.5%)	4 (10%)	13 (7.6%)	11 (7.4%)	11 (11%)	3 (5.4%)
Urine leakage	6	2	-	1	1	2	-
Infectious urinoma	1	2	-	1	1	2	1
Recurrent UPJ-stenosis	7	9	-	6	7	4	2
Hematoma, bleeding	0	6	-	1	1	2	-
Colonic lesion	0	-	-	1	1	1	-
Stone formation	0	1	4	3	-	-	-
Grade 4	0	1 (0.5%)	0	1 (0.6%)	1 (0.7%)	1 (1%)	0
Pulmonary embolism	0	1	-	-	-	-	-
Cardiac infarction	0	-	-	1	-	-	-
Congestive heart failure	0	-	-	-	1	1	-
Grade 5	0	0	0	0	0	0	0
Death	-	-	-	-	-	0	0
TOTAL	32 (13.5%)	30 (15.8%)	9 (22.5%)	20 (11.8%)	19 (12.9%)	18 (18%)	7 (12.6%)

UPJ=ureteropelvic junction.

The comparative analysis between the cases of patients affected with primary and secondary UPJO showed a significantly longer operative time and hospital stay as well as an higher intraoperative blood loss for patients who presented with recurrent UPJO. Furthermore, patients with secondary UPJO showed a significantly higher percentage of intraoperative (30% vs 2.6%) and postoperative (60% vs 11.5%) incidents.

Nine (3.8%) cases in our series resulted in intraoperative incidents that is a percentage consistent with that reported in the literature.¹⁴

There were 1.8% of patients who experienced an intraoperative incident related to the incorrect positioning of the Double-J stent because the distal tip was at the level of the distal ureter. All of these cases (4) occurred with female patients. Intraoperative management by cystoscopic repositioning was performed on all cases. Other authors reported similar incidents within a comparable range (1.2% of patients).¹⁵ Because of our practice of positioning the Double-J stent under cystoscopic and fluoroscopic control, no male patients experienced this complication.

Only one (0.4% of patients) case of injury to the lower pole artery took place that required clamping of the vessel. Other authors reported a higher percentage of an incident of this nature with a percentage up to 2.5% of patients.^16,17

The most severe intraoperative complication (grade III) occurred because the ureteral stent was wrapped up in the running suture of the pyeloplasty, which occurred in the very first phase of practicing the technique while in a learning curve. No other author previously reported a similar complication.

Thirty-two (13.6%) patients in our series experienced postoperative complications. Other authors described similar complications with an incident percentage range from 11.8% to 22.5%.^14,18,19

The most frequent postoperative complication was urine leakage (2.5%) graded as IIIa according to the Clavien-Dindo system because of the need for interventional management through the placement of a percutaneous nephrostomy. In our experience, when such a complication occurs, rapid management is necessary so as to avoid the formation of a urinoma that could lead to peritonitis.

The same kind of complication was reported, albeit with a higher percentage (6.9%), from Martina and coworkers²⁰ in their large experience of retroperitoneoscopic pyeloplasty. These authors suggested conservative management of the urinary leakage complication, which is possible because of the retroperitoneal approach.

The most severe postoperative complication (grade IIIb) was the development of infectious urinoma leading to peritonitis that necessitated surgical reintervention.

As previously described under intraoperative complications, the entanglement of the ureteral stent in the running suture determined urine leakage with consequent formation of a large urinoma that necessitated open surgical reintervention on the ninth postoperative day to replace the ureteral stent and drain the urinoma. In this case, we opted for an open approach to ensure better drainage of the peritoneal urinoma and correct placement of the ureteral stent.

The five (2.1%) patients who presented with urinary tract infections were treated by specific antimicrobial therapy.

Recurrent UPJO is reported in 7 (3%) patients in our series. All of these patients underwent a second laparoscopic pyeloplasty. Other authors report a similar percentage for recurrent UPJO.¹⁴ In our experience, a second laparoscopic approach is technically feasible and allows for the definitive resolution of the obstruction.

As expected, the overall incidence complication rate was inversely proportionate to the improvement in laparoscopic skill over the course of the learning curve. An increase from 4% to 12% of intraoperative complications, however, was experienced from phase 1 to phases 2 to 3. This increase in the intraoperative complication rate during phases 2 to 3 can be explained by two factors: (1) New surgeons were introduced to the team; (2) more progressively challenging cases were encountered that had hitherto been excluded during phase 1. A steady decrease from 32% (phase 1) to 3.6% (phase 5) was found for postoperative complications incidence with the first significant incidence drop after the first 75 cases (from 28% to 9.3%).

In our experience, the most delicate surgical step is the insertion of the ureteral stent because, if inserted incorrectly, it can cause time-consuming intraoperative complications or induce moderate to severe postoperative complications. For this reason, we refined our technique and started to routinely perform some modifications such as retrograde insertion in female patients and insertion under fluoroscopic and cystoscopic control at the end of the operation in male patients.

Particular attention should be given to the early postoperative phase so as to monitor for eventual urine leakage, which could lead to a severe complication that would necessitate active management.

A recent study conducted in a small cohort of patients with limited follow-up suggests that a stentless LP is a feasible technique with a minimal incidence of postoperative complications, although is likely related to meticulous surgical technique and ability to minimize laxity on the suture line with the aid of additional clips.²¹

Limitations of the present study are the retrospective method of the data analysis and the inclusion of all consecutive cases performed by different surgeons, although undergoing a similar learning curve.

Conclusions

Our retrospective analysis confirms that transperitoneal pyeloplasty is an efficacious and safe procedure resulting in a success rate of 97% and a concomitant low level of intraoperative (3.8%) and postoperative complications (13.6%). Major complications necessitating active management occurred in a low percentage of cases (5.9% of patients). The most frequent intraoperative incident was the misplacement of the Double-J stent with the distal tip at the level of the distal ureter, while the most common postoperative complication was urine leakage which, in the case of the transperitoneal approach, necessitates early active management to avoid potentially severe consequences.

Footnotes

Disclosure Statement

No competing financial interests exist.

Abbreviations Used

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