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JOURNAL OF ENDOUROLOGY Volume 28, Number 12, December 2014 ª Mary Ann Liebert, Inc. Pp. 1487–1494 DOI: 10.1089/end.2014.0421
Ureteroscopy and Percutaneous Procedures
Totally Tubeless Versus Standard Percutaneous Nephrolithotomy for Renal Stones: Analysis of Clinical Outcomes and Cost Sae Woong Choi, MD, Kang Sup Kim, MD, Jeong Ho Kim, MD, Yong Hyun Park, MD, PhD, Woong Jin Bae, MD, PhD, Sung-Hoo Hong, MD, PhD, Ji Youl Lee, MD, PhD, Sae Woong Kim, MD, PhD, Tae-Kon Hwang, MD, PhD, and Hyuk Jin Cho, MD, PhD
Abstract
Purpose: To evaluate the safety and cost-effectiveness of a totally tubeless percutaneous nephrolithotomy (PCNL) by comparing the clinical outcomes and cost analysis between standard PCNL and totally tubeless PCNL for renal stones. Patients and Methods: From June 2012 to September 2013, a total of 121 patients with renal stones who underwent totally tubeless or standard PCNL by two experienced surgeons were retrospectively evaluated by group. According to the surgeon’s preference for the nephrostomy tube and/or ureteral stent, the present study was designed to be divided into Group 1 and Group 2. Group 1 was performed by one surgeon (H.J. Cho) who preferred a totally tubeless PCNL and Group 2 was performed by the other surgeon (S.H. Hong) who preferred a standard PCNL. We excluded bilateral renal stones, multiple approach, whole staghorn calculi, and previous renal surgery. Patient and stone characteristics, intraoperative and postoperative parameters, and cost analysis were compared between the two groups. Results: There were no significant differences in the patient demographics between groups. Mean stone burden was 501.5 – 361.1 mm2 in Group 1 v 535.2 – 353.1 mm2 in Group 2 (P = 0.651). Length of hospital stay (1.72 – 0.58 v 4.10 – 1.88 days, P < 0.001), postoperative pain scores using a visual analog scale (day 0: P < 0.001, day 1: P = 0.002), and analgesia requirements (33.2 – 21.3 v 45.2 – 19.5 mg, P = 0.005) for Group 1 v Group 2 showed significant differences. The stone-free rate was 86.4% v 89.8% in Group 1 and Group 2, respectively (P = 0.609). There were no significant differences in overall complications between groups (P = 0.213). Mean total medical treatment costs in Groups 1 and 2 were 2398.22 – 549.1 USD and 2845.70 – 824.2 USD, respectively (P = 0.002). Conclusions: Many clinical outcomes in the totally tubeless PCNL showed comparable or better results than standard PCNL. We believe that totally tubeless PCNL is an acceptable, safe, and cost-effective alternative to standard PCNL for the treatment of renal stones.
Introduction
P
ercutaneous nephrolithotomy (PCNL) is known as a standard surgical treatment of large and complicated renal calculi.1 The development of surgical technique and instruments has contributed to the modification of PCNLs with a smaller working sheath, nephroscope, and nephrostomy tube or even without a nephrostomy tube or ureteral stent.2–7 Totally tubeless PCNL is a recent modification without the nephrostomy tube and ureteral stent and
has some potential advantages, including reduced postoperative pain and analgesia requirement without stent-related symptoms, shorter hospitalization and convalescence, and lower cost.2,5,6,8–10 However, totally tubeless PCNL has not been widely accepted due to some limitations.7,11 Most of the studies on totally tubeless PCNL were designed such that intraoperative procedures were uncomplicated with complete stone clearance and preoperatively selected patients had satisfied strict inclusion criteria.2,5,6,9,10 Most of the casecontrolled and randomized studies performed randomization
Department of Urology, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
1487
Downloaded by Kings College London-journal Section from online.liebertpub.com at 11/13/17. For personal use only.
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on the completion of uncomplicated PCNL as decided by the subjective judgment and experience of a single surgeon.5,6,8,10 We surmised that these study designs had a potential for selection bias. For this reason, our study was designed to be performed as a totally tubeless or standard approach, before the PCNL procedure, by two experienced surgeons who had a different preference for the nephrostomy tube and/or ureteral stent, instead of determination of the insertion of nephrostomy tube and/or ureteral stent at the completion of an uncomplicated PCNL. We compared clinical outcomes and cost analysis between the two groups to identify the safety and cost-effectiveness of totally tubeless PCNL for renal stones. Patients and Methods Patient selection and study design
From June 2012 to September 2013, we performed 121 PCNLs for renal stones, including 54 of totally tubeless PCNLs and 67 of standard PCNLs. During this study period, all PCNL procedures were predetermined by two experienced surgeons (H.J. Cho and S.H. Hong) who had different preferences for the placement of a nephrostomy tube and/or ureteral stent. The present study was designed such that Group 1 was performed by one surgeon (H.J. Cho) who preferred a totally tubeless PCNL, and Group 2 was performed by the other surgeon (S.H. Hong) who preferred a standard PCNL. We excluded bilateral renal stones (defined as cases that clinically needed bilateral PCNL), multiple approach (defined as an approach requiring more than two nephroscopy tracts), whole staghorn calculi (defined as stones occupying ‡80% of the renal pelvis and renal caliceal system12), and
previous urinary tract surgery. Twenty-eight patients were excluded based on these exclusion criteria. Thus, Group 1 and Group 2 had 44 and 49 patients, respectively. A preoperative radiologic evaluation of the kidneys, ureters, and bladder (KUB) and noncontrast computerized tomography (CT) were performed in all patients. Stone burden was measured by the longitudinal and transverse diameters (mm2) using a preoperative CT scan. The total stone burden was the sum of burdens of all stones found in the preoperative CT scan.13,14 On the first postoperative day, all patients underwent routine plain radiography to check for residual stone fragments. Selected cases were postoperatively evaluated by a noncontrast CT scan or renal ultrasonography to determine the suspected residual stones, radiolucent stones, or complications. In cases of supracostal approach, the plain chest film was performed to identify a hydro/pneumothorax. We compared patient and stone characteristics between the two groups, including age, sex, body–mass index (BMI), ASA score, history of extracorporeal shock wave lithotripsy (SWL), radiopacity, stone laterality, multiplicity and location of stones, and stone burden (Table 1). The two groups were compared with regard to intraoperative parameters, including mean operative time, approach, puncture site, and postoperative parameters, including change in hemoglobin and serum creatinine values, analgesia requirements, postoperative pain score, transfusion rate, and length of hospital stay. The visual analog scale (VAS) pain score (0–10: 0, no pain; 10, worst possible pain) and analgesia requirements were used to evaluate postoperative pain. The VAS score was recorded on postoperative day 0 (at 6 hours after the end of the operation), postoperative day 1, and discharge day.
Table 1. Patient Demographics and Stone Characteristics Characteristics Number of patients Mean age (years) Sex, male:female (%) Stone laterality Left:Right (%) BMI (kg/m2) ASA score (%) 1 2 3 Prior SWL (%) Radiopacity Radiopaque stones (%) Radiolucent stones (%) Multiplicity and position of stones (%) Single Upper calix Middle calyx Lower calyx Pelvis, UPJ Partial staghorn Multiple Partial staghorn Stone burden (longitudinal · transverse diameters, mm2)
Group 1
Group 2
44 53.2 – 14.9 32:12 (72.7:27.3)
49 56.0 – 13.4 34:15 (69.4:30.6)
21:23 (47.7:52.3) 25.3 – 2.9
32:17 (65.3:34.7) 24.9 – 3.0
16 25 3 7
(36.4) (56.8) (6.8) (15.9)
39 (88.6) 5 (11.4)
16 30 3 6
(32.7) (61.2) (6.1) (12.2)
P-value 0.339 0.723 0.087 0.554 0.944
0.611 0.675
42 (85.7) 7 (14.3) 0.013
31 (70.5) 2 (4.5) 5 (11.4) 2 (4.5) 20 (45.0) 2 (4.5) 13 (29.5) 2 (4.5) 501.5 – 361.1
22 (44.8) 2 (4.1) 6 (12.2) 1 (2.0) 8 (16.3) 5 (10.2) 27 (56.2) 4 (8.1) 535.2 – 353.1
0.651
ASA = American Society of Anesthesiologists; BMI = body–mass index; SWL = shock wave lithotripsy; UPJ = ureteropelvic junction.
Downloaded by Kings College London-journal Section from online.liebertpub.com at 11/13/17. For personal use only.
TOTALLY TUBELESS PCNL FOR RENAL STONES
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Analgesia requirements were recorded by a chart review of all oral and parenteral or intramuscular medication given while in the hospital stay. All medications were converted to morphine equivalent dosage. Patients were discharged from the hospital when patients were hemodynamically stable and pain was controllable with oral medications. Re-PCNL, SWL, ureterorenoscopic lithotripsy (URSL), and chemolysis were considered as secondary treatment for the residual renal stones (more than 4 mm), when indicated. All patients were followed up at postoperative 1 week, 1 month, and 3 months. At each visit, plain KUB film, urine analysis, complete blood count, and serum creatinine were routinely checked. We performed noncontrast CT for selected cases such as suspected residual stones, radiolucent stones, and complications. The results were classified as stone free, clinically insignificant residual fragments (CIRFs), and residual stones (more than 4 mm). CIRFs were considered to be £4 mm, nonobstructing, noninfectious, and asymptomatic residual fragments found on postoperative evaluation.15 Effective PCNL was considered if the patient was stone free (no residual fragments) on the intraoperative visual and fluoroscopic check and the postoperative radiologic evaluation. Effectiveness quotient (EQ) in both groups was calculated by the following formula: (percentage of stone free)/(100 + percentage of retreatment + percentage of auxiliary treatment).16 Medical records and data for this study were retrospectively obtained and reviewed. This study was approved by our Institutional Review Board.
Calculation of medical costs and statistical analysis
The total medical costs were calculated as the sum of the costs of overall hospitalization, the costs of additional treatment (complication-related treatment), and the costs of secondary treatment (treatment for residual stones). The costs of overall hospitalization included room and board, pharmacy and fluid, laboratory test, radiology test, nursing care charges, anesthesia, operating fee, and surgical supplies. The costs of additional treatment were the costs of readmission for major complication, Double-J catheter insertion costs, and follow-up clinic Double-J catheter removal costs. We included the costs of the secondary treatment in the two groups. Common costs, including preoperative and postoperative OPD visit costs, were not considered in this study. We obtained detailed cost information from the electronic medical records reported by the hospital billing department at our institute. All costs of outpatient and inpatient were applied to the National Health Insurance Service (NHIS). Costs of instruments did not change in this study period. The outcomes of both groups were compared using the Student’s t-tests for continuous variables with normal distributions. A chi-square test or Fisher’s exact test was used for the analysis of qualitative data. Data are reported as the mean – the standard deviation. P values
JOURNAL OF ENDOUROLOGY Volume 28, Number 12, December 2014 ª Mary Ann Liebert, Inc. Pp. 1487–1494 DOI: 10.1089/end.2014.0421
Ureteroscopy and Percutaneous Procedures
Totally Tubeless Versus Standard Percutaneous Nephrolithotomy for Renal Stones: Analysis of Clinical Outcomes and Cost Sae Woong Choi, MD, Kang Sup Kim, MD, Jeong Ho Kim, MD, Yong Hyun Park, MD, PhD, Woong Jin Bae, MD, PhD, Sung-Hoo Hong, MD, PhD, Ji Youl Lee, MD, PhD, Sae Woong Kim, MD, PhD, Tae-Kon Hwang, MD, PhD, and Hyuk Jin Cho, MD, PhD
Abstract
Purpose: To evaluate the safety and cost-effectiveness of a totally tubeless percutaneous nephrolithotomy (PCNL) by comparing the clinical outcomes and cost analysis between standard PCNL and totally tubeless PCNL for renal stones. Patients and Methods: From June 2012 to September 2013, a total of 121 patients with renal stones who underwent totally tubeless or standard PCNL by two experienced surgeons were retrospectively evaluated by group. According to the surgeon’s preference for the nephrostomy tube and/or ureteral stent, the present study was designed to be divided into Group 1 and Group 2. Group 1 was performed by one surgeon (H.J. Cho) who preferred a totally tubeless PCNL and Group 2 was performed by the other surgeon (S.H. Hong) who preferred a standard PCNL. We excluded bilateral renal stones, multiple approach, whole staghorn calculi, and previous renal surgery. Patient and stone characteristics, intraoperative and postoperative parameters, and cost analysis were compared between the two groups. Results: There were no significant differences in the patient demographics between groups. Mean stone burden was 501.5 – 361.1 mm2 in Group 1 v 535.2 – 353.1 mm2 in Group 2 (P = 0.651). Length of hospital stay (1.72 – 0.58 v 4.10 – 1.88 days, P < 0.001), postoperative pain scores using a visual analog scale (day 0: P < 0.001, day 1: P = 0.002), and analgesia requirements (33.2 – 21.3 v 45.2 – 19.5 mg, P = 0.005) for Group 1 v Group 2 showed significant differences. The stone-free rate was 86.4% v 89.8% in Group 1 and Group 2, respectively (P = 0.609). There were no significant differences in overall complications between groups (P = 0.213). Mean total medical treatment costs in Groups 1 and 2 were 2398.22 – 549.1 USD and 2845.70 – 824.2 USD, respectively (P = 0.002). Conclusions: Many clinical outcomes in the totally tubeless PCNL showed comparable or better results than standard PCNL. We believe that totally tubeless PCNL is an acceptable, safe, and cost-effective alternative to standard PCNL for the treatment of renal stones.
Introduction
P
ercutaneous nephrolithotomy (PCNL) is known as a standard surgical treatment of large and complicated renal calculi.1 The development of surgical technique and instruments has contributed to the modification of PCNLs with a smaller working sheath, nephroscope, and nephrostomy tube or even without a nephrostomy tube or ureteral stent.2–7 Totally tubeless PCNL is a recent modification without the nephrostomy tube and ureteral stent and
has some potential advantages, including reduced postoperative pain and analgesia requirement without stent-related symptoms, shorter hospitalization and convalescence, and lower cost.2,5,6,8–10 However, totally tubeless PCNL has not been widely accepted due to some limitations.7,11 Most of the studies on totally tubeless PCNL were designed such that intraoperative procedures were uncomplicated with complete stone clearance and preoperatively selected patients had satisfied strict inclusion criteria.2,5,6,9,10 Most of the casecontrolled and randomized studies performed randomization
Department of Urology, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
1487
Downloaded by Kings College London-journal Section from online.liebertpub.com at 11/13/17. For personal use only.
1488
CHOI ET AL.
on the completion of uncomplicated PCNL as decided by the subjective judgment and experience of a single surgeon.5,6,8,10 We surmised that these study designs had a potential for selection bias. For this reason, our study was designed to be performed as a totally tubeless or standard approach, before the PCNL procedure, by two experienced surgeons who had a different preference for the nephrostomy tube and/or ureteral stent, instead of determination of the insertion of nephrostomy tube and/or ureteral stent at the completion of an uncomplicated PCNL. We compared clinical outcomes and cost analysis between the two groups to identify the safety and cost-effectiveness of totally tubeless PCNL for renal stones. Patients and Methods Patient selection and study design
From June 2012 to September 2013, we performed 121 PCNLs for renal stones, including 54 of totally tubeless PCNLs and 67 of standard PCNLs. During this study period, all PCNL procedures were predetermined by two experienced surgeons (H.J. Cho and S.H. Hong) who had different preferences for the placement of a nephrostomy tube and/or ureteral stent. The present study was designed such that Group 1 was performed by one surgeon (H.J. Cho) who preferred a totally tubeless PCNL, and Group 2 was performed by the other surgeon (S.H. Hong) who preferred a standard PCNL. We excluded bilateral renal stones (defined as cases that clinically needed bilateral PCNL), multiple approach (defined as an approach requiring more than two nephroscopy tracts), whole staghorn calculi (defined as stones occupying ‡80% of the renal pelvis and renal caliceal system12), and
previous urinary tract surgery. Twenty-eight patients were excluded based on these exclusion criteria. Thus, Group 1 and Group 2 had 44 and 49 patients, respectively. A preoperative radiologic evaluation of the kidneys, ureters, and bladder (KUB) and noncontrast computerized tomography (CT) were performed in all patients. Stone burden was measured by the longitudinal and transverse diameters (mm2) using a preoperative CT scan. The total stone burden was the sum of burdens of all stones found in the preoperative CT scan.13,14 On the first postoperative day, all patients underwent routine plain radiography to check for residual stone fragments. Selected cases were postoperatively evaluated by a noncontrast CT scan or renal ultrasonography to determine the suspected residual stones, radiolucent stones, or complications. In cases of supracostal approach, the plain chest film was performed to identify a hydro/pneumothorax. We compared patient and stone characteristics between the two groups, including age, sex, body–mass index (BMI), ASA score, history of extracorporeal shock wave lithotripsy (SWL), radiopacity, stone laterality, multiplicity and location of stones, and stone burden (Table 1). The two groups were compared with regard to intraoperative parameters, including mean operative time, approach, puncture site, and postoperative parameters, including change in hemoglobin and serum creatinine values, analgesia requirements, postoperative pain score, transfusion rate, and length of hospital stay. The visual analog scale (VAS) pain score (0–10: 0, no pain; 10, worst possible pain) and analgesia requirements were used to evaluate postoperative pain. The VAS score was recorded on postoperative day 0 (at 6 hours after the end of the operation), postoperative day 1, and discharge day.
Table 1. Patient Demographics and Stone Characteristics Characteristics Number of patients Mean age (years) Sex, male:female (%) Stone laterality Left:Right (%) BMI (kg/m2) ASA score (%) 1 2 3 Prior SWL (%) Radiopacity Radiopaque stones (%) Radiolucent stones (%) Multiplicity and position of stones (%) Single Upper calix Middle calyx Lower calyx Pelvis, UPJ Partial staghorn Multiple Partial staghorn Stone burden (longitudinal · transverse diameters, mm2)
Group 1
Group 2
44 53.2 – 14.9 32:12 (72.7:27.3)
49 56.0 – 13.4 34:15 (69.4:30.6)
21:23 (47.7:52.3) 25.3 – 2.9
32:17 (65.3:34.7) 24.9 – 3.0
16 25 3 7
(36.4) (56.8) (6.8) (15.9)
39 (88.6) 5 (11.4)
16 30 3 6
(32.7) (61.2) (6.1) (12.2)
P-value 0.339 0.723 0.087 0.554 0.944
0.611 0.675
42 (85.7) 7 (14.3) 0.013
31 (70.5) 2 (4.5) 5 (11.4) 2 (4.5) 20 (45.0) 2 (4.5) 13 (29.5) 2 (4.5) 501.5 – 361.1
22 (44.8) 2 (4.1) 6 (12.2) 1 (2.0) 8 (16.3) 5 (10.2) 27 (56.2) 4 (8.1) 535.2 – 353.1
0.651
ASA = American Society of Anesthesiologists; BMI = body–mass index; SWL = shock wave lithotripsy; UPJ = ureteropelvic junction.
Downloaded by Kings College London-journal Section from online.liebertpub.com at 11/13/17. For personal use only.
TOTALLY TUBELESS PCNL FOR RENAL STONES
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Analgesia requirements were recorded by a chart review of all oral and parenteral or intramuscular medication given while in the hospital stay. All medications were converted to morphine equivalent dosage. Patients were discharged from the hospital when patients were hemodynamically stable and pain was controllable with oral medications. Re-PCNL, SWL, ureterorenoscopic lithotripsy (URSL), and chemolysis were considered as secondary treatment for the residual renal stones (more than 4 mm), when indicated. All patients were followed up at postoperative 1 week, 1 month, and 3 months. At each visit, plain KUB film, urine analysis, complete blood count, and serum creatinine were routinely checked. We performed noncontrast CT for selected cases such as suspected residual stones, radiolucent stones, and complications. The results were classified as stone free, clinically insignificant residual fragments (CIRFs), and residual stones (more than 4 mm). CIRFs were considered to be £4 mm, nonobstructing, noninfectious, and asymptomatic residual fragments found on postoperative evaluation.15 Effective PCNL was considered if the patient was stone free (no residual fragments) on the intraoperative visual and fluoroscopic check and the postoperative radiologic evaluation. Effectiveness quotient (EQ) in both groups was calculated by the following formula: (percentage of stone free)/(100 + percentage of retreatment + percentage of auxiliary treatment).16 Medical records and data for this study were retrospectively obtained and reviewed. This study was approved by our Institutional Review Board.
Calculation of medical costs and statistical analysis
The total medical costs were calculated as the sum of the costs of overall hospitalization, the costs of additional treatment (complication-related treatment), and the costs of secondary treatment (treatment for residual stones). The costs of overall hospitalization included room and board, pharmacy and fluid, laboratory test, radiology test, nursing care charges, anesthesia, operating fee, and surgical supplies. The costs of additional treatment were the costs of readmission for major complication, Double-J catheter insertion costs, and follow-up clinic Double-J catheter removal costs. We included the costs of the secondary treatment in the two groups. Common costs, including preoperative and postoperative OPD visit costs, were not considered in this study. We obtained detailed cost information from the electronic medical records reported by the hospital billing department at our institute. All costs of outpatient and inpatient were applied to the National Health Insurance Service (NHIS). Costs of instruments did not change in this study period. The outcomes of both groups were compared using the Student’s t-tests for continuous variables with normal distributions. A chi-square test or Fisher’s exact test was used for the analysis of qualitative data. Data are reported as the mean – the standard deviation. P values
