Outcomes and Complications of Percutaneous Nephrolithotomy (PCNL) at Al-ribat Urology Center (Omer Sawi Hospital)

Objective: Percutaneous nephrolithotomy generally is safe, effective, and associated with a few but speci�c complications. However, the de�nition of complications of PCNL and their management still lacks consensus. We aimed to evaluate the Technique, Outcome, and Complication of percutaneous Nephrolithotomy at Al-ribat Urology Center (Omer Sawi Hospital). methods : A prospective, institutional-based cross-sectional study, the study investigated all patients presented to the study area with renal stones The data was collected by a pre-designed questionnaire �lled out inside the theater during the surgery and 1-month follow-up by phone calls. Result: the study assessed the outcome of PCNL among 28 patients. The study found that the mean size of stones recorded was 1.25 cm, and the stones were on the left and right kidneys in 53.6%, and 46.4% respectively. Stones present by a percentage of 10.7%,28.6%, and 53.6% in the upper and lower calyx and pelvis respectively. The stones were rounded in 78.6% and staghorn in 21.4%. the stone was single in 53.6% and multiple in 46.4%. all operations were done under �uoroscopy guidance. Patients were supine in 25% and prone in 75% of the operations. Injury to the surrounding organs did not occur. Mild bleeding occurs in 10.7% of the patients, in which blood transfusion was necessary. Extravasation of �uid occurs in 10.7%. Fever occurs in 42.9%. Most of the patients stay for 1 day postoperatively 57.1%. Conclusion: This study demonstrated that PCNL is a safe elective, minimally invasive surgical modality with good outcomes and lower incidences of major complications.


INTRODUCTION
Almost one-third of the surgical workload in a typical active urologic department is related to the treatment of urinary calculosis (1) for which there are a variety of techniques available.Before the development of less invasive treatments, most patients with symptomatic renal calculi underwent open surgical lithotomy.(2,3).In addition to surgery, current options for interventional management of renal stones also include ureteroscopy, percutaneous nephrolithotomy (PCNL), and shockwave lithotripsy (SWL).The use of PCNL became initially widespread after the rst description in 1976 (4), later on, diminished with the introduction of noninvasive SWL in the early 1980s.Recent studies have indicated a resurgence in the use of PCNL during the last 10 years, (2, 5, and 6) which attributed to two factors.First, awareness of the limitations of SWL.Second, improvements in the PCNL procedure, have led to reductions in morbidity and yielded stone-free rates of > 90% in treated patients.(7,8) Indications for treatment, renal access, and available equipment have been identi ed to impact treatment outcomes and complication rates with PCNL.Speci cally, the introduction of balloon dilation of the tract, use of exible nephroscopes, improved intracorporeal lithotripters (including ultrasound, pneumatic devices, and the holmium: yttrium-aluminum-garnet laser), and the trend to smaller or no nephrostomy tubes have contributed to increased e cacy of percutaneous stone disintegration and decreases in the overall morbidity rates for PCNL.Such improvements in techniques for percutaneous stone removal have resulted, for example, in signi cant decreases in transfusion rates, which were 25% in early reports and It has decreased from 1-2% in more recent studies.( 9) PCNL has demonstrated safety and e cacy in the management of large, multiple, or complex renal stones.(10) Other indications are the composition, site of the stone, and the existence of obstruction distal to it, the certainty for the nal result, the failure or the contraindication to SWL, and the presence of renal anatomic variation.Inherent with the developmental progress of PCNL is an increase in variations of the technique, demonstrated through the implementation of PCNL with the patient in various positions.Other major variables in the technique include imaging modality, site of kidney puncture, method of tract dilation, size of nephroscopes and tubes, and use of kidney drainage (if any) after PCNL.In addition, while an interventional radiologist has traditionally been needed to acquire renal access for percutaneous renal surgery, increasingly urologists have performed this procedure without the assistance of a radiologist and with similar success.(11,12) The study aims to assess the outcome of percutaneous Nephrolithotomy at Al-ribat hospital.

MATERIALS AND METHODS
This is a prospective, institutional-based cross-sectional study, during the period from November 2019 -April 2020.At Al-rebat Urology Center (Omer Sawi Hospital) in Sudan, Khartoum.The target population was all patients presented to Al-rebat Urology Center (Omer Sawi Hospital) who were subjected to PCNL. which included 28 patients who met the Inclusion criteria( stone more than 2 cm in diameter, residual post-open surgery, multiple kidney stones, and high-density stones) and exclusion criteria(patients having coagulopathy, pregnancy, and patients who refuse to participate).
A multistage strati ed random sampling method was used.The sample size for this study was calculated via The following equation n = z2 P(1-P)/d2.With a 95% Con dence Interval (CI), 50% response distribution and 0.05 margin of error, a sample of 28 participants can be considered as a minimal sample to represent the population The data was collected by a pre-designed questionnaire lled out inside the theater during the surgery and 1-month follow-up by phone calls.The data collected was analyzed using The SPSS Statistics version 23 (IBM Corporation, Armonk, NY, USA).Descriptive statistics were done.Categorical variables were described as numbers and percentages.The Pearson Chi-square was used, and P was less than 0.05.Verbal consent was obtained from participants before data collection, con dentially concern considering data as it was only used for research Issues.Hospital permissions were obtained before data collection.

Results
Different age groups are present in our study, the youngest patient was 6 years old while the eldest was 75 years old with a mean age of 23.9 years.There were 17 males (60.7%) and 11 females (39.3%)Patients in our study came from different parts of Sudan.Various stone sizes are recorded most of them are between 2-4 the rest of them are above 4cm and the mean stone size of 2.25cm.The calculi were on the right side in 13 patients (46.4%) and on the left side in 15 patients (53.6%).The calculi were in the upper pole in 10.7 percent, the pelvis in 53.6 percent, the lower pole in 28.6 percent, and both the upper and middle pole in 7.1 percent of the cases.Out of 28 stones recorded in our study, 22 of them were rounded (78.6%) and 6 of them were Staghorn in shape (21.4%).Hard Stones were recorded in 25 patients (89.3%) and Matrix (muddy or like clay) Stones in 3 patients (10.7%).Stones can present according to visibility under X-ray as Radiopaque (visible under X-ray) or radiolucent (Not visible under Xray nor CT)Both are presented in our study as follows.They were solitary in 53.6 percent and multiple in 46.4 percent of the cases.All 28 patients underwent the surgery under uoroscopy guidance.The majority of patients were treated in the prone position (75.0%), and others were treated supine position (25.0%).Access was gained through the lower pole in 15 cases (53.6%).Puncture of the middle pole was performed in 7 cases (25%) and of the upper pole in 6 cases (21.4%).The time of the overall procedure ranges from less than 20 minutes to 120 minutes with an average time of 27.9 minutes calculated from the time of puncture not including retrograde and positioning.For PCNL a rigid nephroscope with a caliber of 12 F was used in 12 patients (42.9%) and a caliber of 26 F was used in 16 patients (57.1%).Placement of a nephrostomy after the completion of PCNL was done on 16 out of 28 patients (57.1%).
Placement of a nephrostomy after the completion of PCNL was done on 16 out of 28 patients (57.1%).Placement of a double J after the completion of PCNL was done on 16 out of 28 patients (57.1%).In 12 out of 28 patients (42.9%), there was no need for the placement of a nephrostomy tube or double J. Out of 28 patients who underwent the surgery 19 of them were stone-free (67.9%) from the rst look, 7 of them required a second session (25.0%) and 2 patients required more than 2 sessions (7.1%).Stone-free rate was achieved in 26 patients (85.7%) and the rest of the cases required more than 2 sessions that we did not record it.Serious complications such as injury to neighboring organs (lung, intestine, liver, spleen, jejunum, pleura) or loss of the kidney did not occur.Mild bleeding occurred in 3 patients 10.7% for which blood transfusion was necessary and no surgical intervention for bleeding since any hemorrhage ceased spontaneously.Extravasation is a common incident during PCNL, which can potentially lead to untoward consequences and it occurred in 3 patients 10.7%.Fever is the most common postoperative complication and only one spike of fever postoperatively is considered positive for pyrexia.Another post-operative complication in our study is postoperative leak from the wound which includes either urine leakage or blood leakage occurs in 4 patients 14.3%.Arterio-venous stula is a rare complication which does not occur.Most of the patients stayed in the hospital for 1 day 57.1%, 25% stayed for 3-4 days and the rest stayed for more than 4 days 17.9% with a mean time of 2.03 days for patients' age groups.

Discussion
This study included 28 patients, 17 of them were males 60.7% and 11 were females 39.3%.WJ Lee (14), report 312 men 53.6%, and 270 women 46.4% in contrast to J.E. A. WICKHAM (17) where he demonstrated that 66% of the patients included in his study were males and 34% were females.In our study the age range is between 6-75 years with a mean age of 23.9 years Shahzad Ali (19) reported that in his study the mean age was 35 ± 9.56 years and WJ Lee (14) reported that the average age in his study was 57 years.*Stonessize was ranging from 2cm to 12cm with a mean stone size of 2.25 in comparison to Sven Lahme (20) who report a mean stone size of 2.4cm which is very similar to our stones recorded in our study.The calculi recorded in our study were on the right side in thirteen patients (46.4%) and on the left side in 15 patients (53.6%), in contrast to Mohanad Moawia Mustafa's ( 13) study who reported that the stones were on the right kidney on 53.6% and left kidney on 46.4%.J.E. A. WICKHAM (17) reported that out of 50 patients, the calculi were on the right side in 21 patients 42%, and on the left side in 29 patients 58% which is quite similar to our study.Access was gained through the lower pole (53.6%), the middle pole (25%), and the upper pole (21.4%) of cases.J.E. A. WICKHAM (17) reports that the upper pole was punctured in 2%, the middle pole in 24% and the lower pole in 74% of the cases.All 28 patients underwent the surgery under uoroscopy guidance because the ultrasound machine was not working.
The mean operative time was 27.9 minutes and this is by far less than the time recorded in other studies.Tolga Akman (22) reported that the mean operative time was 64.9 ± 27.6 minutes.Eduardo Mazzucchi (23) reported that the Mean operative time was 164.6 minutes in the prone and 120.3 minutes in the supine position.Sven Lahme (20) reported that the mean operative time was 99.2 minutes.Nephrostomy was used in (57.1%) of the patients which is less than Mohanad Moawia Mustafa(13) who reported 92.8% of the patients had both DJ (double j) nephrostomy drainage tubes.In our study, the post-operative stone clearance rate was 92.9% which is considered an excellent result when compared to other studies.Similar to our ndings, Jean de la Rosette (18) reported an 89.8% stone-free rate.Whereas Mohanad Moawia Mustafa(13) reports a stone-free rate of 60.8%.Moreover, Mayank Agarwal (21) showed better results all patients were rendered stone free.-Intra-operativecomplications that related to the administration of nephroscope such as pleura, liver, Spleen, Colon, Duodenum and Jejunum injury did not occur and were considered an excellent result in contrast to Maurice Stephan Michel (15) who reported colonic injury in (0.2-0.8%) and pleural injury in (0.0-3.1%).Also, Shahzad Ali (19) reported colonic injury in 0.57%.Mild bleeding occurred in 10.7% for which he received a blood transfusion.This rate is quite acceptable.Mohanad Moawia Mustafa (13) reported that 16.5% of his patients had bleeding and needed blood transfusion.WJ Lee (14) experienced bleeding necessitating transfusion in (12%) of their patient Abdominal extravasation of uid occurred in 10.7% of the patients which is quite acceptable in contrast to WJ Lee (14) who reported that extravasation occurred in 7% of their patients.Maurice Stephan Michel (15) reported that 7% of their patient had extravasation in this study, and fever was seen in 42.9% of the patients.Other literature reported a lower incidence of fever post-operatively Mohanad Moawia Mustafa (13) had less fever as one of PCNL complications than this study, he found that fever occurred in 16.5% of his patients.WJ Lee (14) Reported fever in (23%) of his patients.Maurice Stephan Michel (15) found that fever occurred in 32.1% of the patients.One of the drawbacks of our study was that we did not document the etiology of fever as TWBCs count and our criteria were very strict that only one spike of fever is considered positive for pyrexia.Fever after surgery is the most common complication in our study.This complication is probably related to the poor sterilization technique and It is not a serious complication unless it is associated with other complaints or abnormal investigations.Fever accompanied by several other complications such as infections requiring additional antibiotics as well as a side effect of blood transfusion.-PostoperativeLeak from wound occurred in 14.3% of our patients which is quite high; Shahzad Ali (19) demonstrates that urinary leakage in 8.57% of their patients.-Arterio-venousstula did not occur in our study, in contrast to Gremmo E (16) who reported that arteriovenous stulas occurred in 0.39% of their patients.Most of the patients in this study stayed at the hospital postoperatively for 1 day, the mean postoperative hospital stay was 1.47 days.Mohanad Moawia Mustafa (13) reported that most of the patients (57.7%) stayed for 1-3 days in the hospital, Whereas J.E. A. WICKHAM (17) reported that the mean hospital stay was 8.3 days.

CONCLUSION
This study highlights the safety, good outcomes, and lower incidences of major complications of PCNL.
Small size of stones were found to have better outcome clearance than large size or stag horn stones (p = .030).92.9% of assessed patients had complete stone clearance.Fever was the most common postoperative complications complication and we recommend that better sterilization of equipment and safety hygienic measures should be applied.

Recommendations
We recommend that better sterilization of equipment should be applied and safety hygienic measures should be applied more strictly.PCNL as a surgical procedure has good outcomes and fewer complications and it's better to expand it to all tertiary hospitals with urology departments in Sudan by availing all needed resources in the form of availability of all investigations and treatment even for suggested post-operative complications, skilled and trained health workers and equipped theaters.