Outcomes of Percutaneous Nephrolithotomy Under Local Anesthesia: Outcomes of a Systematic Review of Literature

Abstract

Background:

Several studies have reported on the safety and feasibility of percutaneous nephrolithotomy (PCNL) under local anesthesia (LA). The aim of this systematic review is to assess the perioperative outcomes of PCNL under LA.

Methods:

Three electronic databases, including MEDLINE, EMBASE, and Web of Science, were searched for relevant English-language studies published from January 1980 to March 2023. The systematic review has been performed according to the Cochrane style and the Preferred Reporting Items for Systematic Reviews and Meta-Analysis. The primary outcomes include stone-free rate (SFR) and conversion to general anesthesia (GA). Secondary outcomes include postoperative complications.

Results:

Of 301 articles that were extracted, 42 full-text articles were selected, of which 36 were excluded, yielding a total of 6 articles in our results. A total of 3646 patients were included in this review. The SFR of PCNL under LA ranged between 69.9% and 93.3%. PCNL under LA was not tolerated by 19 (0.5%) patients: 6 patients had conversion to general anesthesia, 2 had conversion to epidural anesthesia, and 11 had their procedure terminated. The overall complication rates varied from 4.8% to 21% across studies. Grade I–II complications were reported in 2.4%–16.7% of cases, while grade III–IV complications were encountered in 0.5%–5% of patients.

Conclusions:

In this review, we found a few studies that examined the outcomes of PCNL under LA, which highlight the feasibility and safety of PCNL under LA and the low conversion rate to GA.

Introduction

Percutaneous nephrolithotomy (PCNL) is considered a first-choice treatment for large renal stones (>2 cm) as it offers the best stone-free rate (SFR) compared with other modalities such as shock wave lithotripsy and retrograde intrarenal surgery (RIRS).¹ PCNL is associated with postoperative complications that are more pronounced in frail and morbidly obese patients and patients with advanced chronic obstructive pulmonary disease (COPD).^2
–4

PCNL is usually performed under general anesthesia (GA) due to pain and the perceived risks of sudden patient movements, resulting in kidney parenchyma injury or pelvicaliceal system perforation; better control of breathing; and better tolerability for patients.^5,6 The disadvantages of GA are associated with pulmonary, vascular, and neurologic systems—problems associated with electrolyte balance and the endotracheal tube especially during the change of position from lithotomy to prone.⁵

Moreover, there are no robust data to support conservative management of staghorn stones.⁷ Therefore, several efforts have been attempted to explore the safety and feasibility of PCNL under local anesthesia (LA), where the side effects of GA itself might affect the outcomes of the surgery, such as in frail patients, elderly patients, and patients with severe COPD. In 2011, Chen et al. reported their early experience of PCNL under LA.⁸ Subsequently, larger studies utilizing different mixtures of LA anesthesia have evaluated SFRs and the tolerability of the procedure.^9
–11

The aim of this systematic review is to assess the outcomes of PCNL under LA. The primary outcomes include SFR and conversion to GA. Secondary outcomes include operative time and complications.

Methods

Evidence acquisition: criteria for considering studies

Inclusion criteria

All studies reporting on PCNL for kidney stone disease, performed under LA with or without sedation.

Studies in the English language reporting on a minimum of 20 patients.

Patients of all age groups.

Exclusion criteria

Animal studies, case reports, and laboratory studies.

Studies of PCNL under GA or neuraxial anesthesia, where data on LA could not be separated for those who underwent general or neuraxial anesthesia.

Studies examining PCNL for nonurolithiasis conditions or ureteral stones.

Studies on PCNL under LA using a previously established tract.

Studies using the same data as a more recent study, where the longest follow-up or largest number of patients were included.

Studies that explicitly did not report SFRs.

Search strategy and study selection

The present systematic review has been performed according to the Cochrane style and the Preferred Reporting Items for Systematic Reviews and Meta-Analysis. Bibliographic databases, namely MEDLINE, EMBASE, and Web of Science, were searched for relevant English-language studies published from January 1980 to March 2023.

The search terms included combinations of “local,” “regional,” “locoregional,” “loco-regional,” “nerve” with “anesthesia,” “anesthesia,” “analgesia,” “block” and “PCNL,” “percutaneous nephrolithotomy,” “percutaneous nephrolithotomy,” “percutaneous nephrolithotripsy,” “percutaneous stone lithotripsy,” “ECIRS,” “endoscopic combined intrarenal surgery,” “miniPCNL,” “mini-PCNL,” “microPCNL,” and “micro-PCNL.” Boolean operators (AND, OR) were used to refine the search.

Filters were applied as appropriate in each search engine to include only human subject studies and articles in English and exclude conference abstracts. A chain search of the references of all included articles was done to identify further relevant articles. Authors of individual studies were contacted if data were unclear or unavailable. A cutoff of 20 patients was decided to include centers with minimum endourological experience in this procedure.

Two reviewers (M.S. and A.F.) independently identified all the studies that fit the inclusion criteria, and discrepancies were resolved after consultation with the senior author (B.K.S.).

Level of evidence, data extraction, and analysis

The levels of evidence and grades of recommendation were assigned according to the Centre for Evidence-Based Medicine (CEBM) guidelines.¹² The following variables were extracted from the studies: the year of publication, country, study type, total number of patients, number of subjects in each arm if applicable, patient age, gender, body mass index, American Society of Anesthesiologists (ASA) score, presence of complete or incomplete staghorn stones, type of LA used, use of sedation, conversion to GA, patient position, and access type (ultrasound [US] vs fluoroscopic vs endoscopic guidance).

These data were collated using Microsoft Excel (version 12.2.4). Because of the heterogeneity of data, a meta-analysis could not be performed and a narrative synthesis was therefore carried out.

Results

Following our search criteria, 301 articles were extracted, of which 131 articles were excluded as they were duplicates and 128 were excluded by title and abstract screening. The remaining 42 full-text articles were reviewed, of which 36 were excluded, yielding a total of 6 articles in our results (Fig. 1, Table 1).

FIG. 1.

Evidence acquisition flow chart.

Table 1.

Study Characteristics and Demographic Information

Study	Type	Country	Age (years)	Male gender	BMI (kg/m²)
Yu et al.¹⁴	Prospective	China	53.6 ± 13.9 (mean, SD)	52 (62.7%)	23.4 ± 4 (mean, SD)
El-shaer et al.¹³	Prospective randomized	Egypt	39.5 (30.3–46) (median, IQR)	42 (70%)	27 (25–30) (median, IQR)
Chen et al.¹¹	Retrospective	China	48.1 ± 13.8 (mean, SD)	547 (56%)	24.9 ± 2.8 (mean, SD)
Ecke et al.¹⁰	Retrospective	Germany	59 (14–90) (median, range)	247 (56.3%)	27.8 (14.7–57.7) (median, range)
Li et al.⁹	Retrospective	China	46.6 (16–87) (mean, range)	1122 (56.1%)	28.4 (18.9–32.6) (mean, range)
Chen et al.⁸	Retrospective	China	39.5 ± 11.7 (mean, SD)	53 (60.2%)	Not reported

BMI = body mass index; IQR = interquartile range; SD = standard deviation.

This review includes one randomized control trial, one prospective study, and four retrospective studies. None of the studies reported power or sample size calculations (Tables 1 and 2). The number of patients included were 3646 (Tables 1 –3). Study characteristics and demographic data are found in Table 1.

Table 2.

Access, Fragmentation Device, and Exit Strategy in the Included Studies

Study	n	Sedation	Position	Sheath size	Access	More than 1 tract	Lithotripsy	Nephrostomy	Double-J stent
Yu et al.¹⁴	83	No	Prone	18–20F	Ultrasound	19 (22.9%)	Laser	28 (33.7%)	100%
El-shaer et al.¹³	60	Yes	Valdiva supine	16F	Ultrasound and fluoroscopy	0 (0%)	Pneumatic	100%	For complications in 3 patients (5%)
Chen et al.¹¹	976	Yes	Prone	18F	Ultrasound	92 (9.4%)	Laser/pneumatic	100%	100%
Ecke et al.¹⁰	439	Yes	Lateral	28F	Ultrasound and fluoroscopy	32 (7.3%)	Ultrasonic	100%	Not reported
Li et al.⁹	2000	Yes	Prone	16–30F	Ultrasound	57 (2.9%)	Laser/pneumatic	100%	100%
Chen et al.⁸	88	Yes	Lateral	18F	Ultrasound	0 (0%)	Pneumatic	100%	100%

Table 3.

Procedural Outcomes in the Reported Studies

Study	n	Operative time	LOS	Complications (grades I–II)	Complications (grades III–IV)	Blood transfusions	SFR	Second look or auxiliary procedure
Yu et al.¹⁴	83	55.1 ± 23.6 minutes	4.1 ± 1.2 days	Total cases: 2 (2.4%)—fever and perirenal hematoma	Total cases: 1 (1.2%)—bleeding requiring transfusion and renal artery embolization	1 (1.2%)	69.9%	Not reported
El-shaer et al.¹³	60	60 (50–76) minutes	1.5 (1.5–2) days	Total cases: 10 (16.7%)—6 fever, 6 UTI, and 6 headache	Total cases: 3 (5%)—needed Double-J stents	0 (0%)	93.3%	4 (6.7%)
Chen et al.¹¹	976	49.7 ± 16.1 minutes	5 ± 1.8 days	Total cases: 74 (7.6%)— transient fever: 28 (2.8%); renal collecting system injury: 8 (0.9%); perirenal hematoma: 3 (0.3%); and blood transfusion: 34 (3.5%)	Total cases: 4 (0.4%)—3 selective renal artery embolization (0.3%) and 1 (0.1%) pleural injury requiring drainage	34 (3.5%)	85.7%	Not reported
Ecke et al.¹⁰	439	42 (9–250) minutes	Not reported	Total cases: 70 (15.9%)—including 55 (12.6%) fever, 2 (0.5%) perirenal hematoma, and 10 (2.3%) blood transfusion	Total cases: 6 (1.4%)—1 colon perforation (0.2%), 2 pleural perforation (0.5%), 2 AV fistula (0.5%), and 1 skin fistula (0.2%)	10 (2.3%)	78.4%	Not reported
Li et al.⁹	2000	48 (20–125) minutes	Not reported	Total cases: 133 (6.7%)— 58 fever (2.9%), 16 renal collecting system injury (0.8%), 4 perirenal hematoma (0.2%), and 65 transfusion (3.3%)	Total cases: 11 (0.55%)— 10 selective renal artery embolization (0.5%) and 1 pleural injury requiring drainage (0.05%)	65 (3.3%)	85.8%	Not reported
Chen et al.⁸	88	89 (56–145) minutes	Not reported	Total cases: 28.9% (both first and second look—n = 121) transient fever: 13.5%; clinically insignificant bleeding: 5.8%; renal colic: 5.8%; and UTI: 3.8%		2 (2.3%)	88.3%	26 (29.5%)

AV = arteriovenous fistula; LOS = length of stay; SFR = stone-free rate; UTI = urinary tract infection.

Use of LA in PCNL

The procedure starts with infiltration of the skin with LA. Thereafter, using a spinal needle (some authors utilize US guidance), the muscle and perirenal capsule are infiltrated with LA.^{8

–11,13,14} A variety of LA mixtures were used, but most studies relied on lidocaine as the main component of the anesthetic mixture. Five of six studies reported on the use of intravenous (IV) sedation as an adjunct to LA (Table 4).

Table 4.

Intraoperative Anesthesia Used and Pain Control

Study	Anesthetic used	Intraoperative pain score (mean VAS score)	Additional analgesia/conversion to GA
Yu et al.¹⁴	Lidocaine (1%, 10 mL) and ropivacaine hydrochloride (1%, 10 mL) from the skin until renal fascia under US guidance	3.9 ± 1	None reported
El-shaer et al.¹³	Lidocaine (2 mL) at the entry point, then LA comprising 9 mL of 2% lidocaine with epinephrine, 9 mL of 0.5% bupivacaine with epinephrine, and 0.8 mL of NaHCO3 is mixed into the renal subcapsular space and then the same mixture is injected along the needle (tract)	2.5 (2–4) (median, IQR)	Required conversion: 1 case
Chen et al.¹¹	Lidocaine (1%, 15–20 mL) from the skin to renal capsule and underlying parenchyma	3.58	Required conversion (excluded): 1 case
Ecke et al.¹⁰	Ropivacaine (7.5 mg/mL, 15–20 mL) from the skin to renal parenchyma along the puncture direction	Reported as the need for IV analgesia or sedation	Required additional IV analgesia or sedation intraoperatively: 213 (48.5%) cases
Li et al.⁹	Lidocaine (1%, 15–20 mL) from the skin to renal capsule and underlying parenchyma	3.62	None reported
Chen et al.⁸	Lidocaine (1%) solution from the skin to renal capsule along the intended tract, total usage <400 mg	3.1	Converted to GA: 4 (4.4%) cases, and converted to epidural anesthesia: 2 (2.2%) cases

GA = general anesthesia; IV = intravenous; LA = local anesthesia; US = ultrasound; VAS = visual analog scale.

Surgical procedure

Position

The most frequent position used during PCNL under LA was the prone position, followed by the lateral position.^8

–11,14 El-Shaer and colleagues reported on the outcomes of PCNL under LA using the modified supine Valdivia position.¹³ None of the included studies examined the feasibility and safety of performing PCNL under LA in the supine position.

Access type

US guidance was used in four studies and two reported using a combination of US and fluoroscopy.^{8

–11,13,14}

Sheath size

Three studies used a standard access sheath (≥22F) and three used a miniaccess sheath (14–20F). None of the procedures were performed using ultramini- or micro-PCNL.^{8

–11,13,14}

Number of tracts

Most of the patients included in this review were treated with single-tract access. However, several authors reported on the use of multiple tracts (as many as five tracts) to complete the procedure without the need for additional anesthesia.^{8

–11,13,14}

Subcostal vs intercostal vs supracostal access

A substantial number of cases were completed using subcostal access; however, supracostal access was obtained in selected cases to perform PCNL under LA without increasing the complication rate or the need to convert to GA.^8–9,11

Lithotripter

A combination of pneumatic and ultrasonic lithotripter and laser was used for PCNL under LA. There was no clear contraindication to the use of any lithotripter under LA.^{8

–11,13,14}

Standard vs tubeless vs totally tubeless

While five of the six studies relied on the use of a nephrostomy tube after PCNL, Yu and colleagues used vacuum-assisted sheaths and reported that 66.7% of their procedures were tubeless.¹⁴ On the other hand, none of the reported cohorts were totally tubeless (Table 1).^{8

–11,13,14}

Perioperative outcomes

Stone-free rate

The SFR of PCNL under LA ranged between 69.9% and 93.3% (Table 2). The need for a second-look PCNL or an auxiliary procedure to treat residual stones was reported by two studies, which ranged between 6.7% and 29.5%.^{8

–11,13,14}

Postoperative complications

Most of the studies used Clavien-Dindo classification to report postoperative complications. The overall complication rates varied from 4.8% to 21% across studies. Grade I–II complications were reported in 2.4%–16.7% of patients, while grade III–IV complications were encountered in 0.5%–5% of patients. There were no reported perioperative mortality rates. The reported blood transfusion (1 unit or more) rates ranged between 0% and 3.5% (Table 2).^{8

–11,13,14}

Operative time and length of stay

The operative time of PCNL under LA ranged between 42 and 89 minutes; however, it was not clear if this included time from anesthesia induction to establishing the PCNL tract.^{8

–11,13,14} Only four studies reported on length of stay (LOS), which varied between 1.5 and 5 days.

Postoperative pain

Several studies used the visual analog scale (VAS) to assess intraoperative pain during the procedure.^{8

–11,13,14} The mean intraoperative VAS ranged between 3.1 and 3.9. PCNL under LA was not tolerated by 19 (0.5%) patients: 6 patients had conversion to general anesthesia, 2 had conversion to epidural anesthesia, and 11 had their procedure terminated. Complete anesthetic and intraoperative pain control details are found in Table 4.

Discussion

Our systematic review is the first article reporting on outcomes of PCNL performed under LA. We identified six articles that described the outcomes of PCNL under LA.^{8

–11,13,14} The SFR ranged from 69.9% to 93%. On the other hand, postoperative complication rates ranged between 2.4% and 16.7% for grade I–II complications and 0.5% and 5% for grade III–IV complications.

Most of the studies included patients with ASA score ≤3; only two studies that assessed the feasibility of PCNL under LA included patients with ASA grade.^4,10,11 Treatment of staghorn stones in highly comorbid and frail patients is a controversial issue among endourologists. While conservative management of staghorn stones might be an option in a select group of patients, staged flexible ureteroscopy has been described to treat staghorn stones in high-risk patients.^7,15

Nevertheless, with the increase in collective experience in performing PCNL, across the globe, there are emerging data showing the safety and feasibility of PCNL under LA, which might be an underutilized treatment modality for these patients.

In a prospective randomized study, there were no significant differences in operative times, LOSs, SFRs, or complication rates of PCNL performed under spinal anesthesia compared with PCNL performed under LA.¹³ While the spinal anesthesia group reported less pain during the surgery compared with the LA group, the latter group had lower postoperative pain at 6 and 12 hours after surgery. In another study, Wang and colleagues compared the outcomes of PCNL under GA and LA and found no significant differences in operative times, LOSs, SFRs, or complication rates of PCNL.¹⁶

Of the 3646 patients included in this review, 8 patients required conversion to another anesthesia modality and 11 cases were terminated due to intraoperative chills.^{8

–11,13,14} This low conversion rate is consistent with what has been previously reported for RIRS procedures under LA. In addition,¹⁷ it emphasizes the importance of pre-op counseling of the patient to manage their intraoperative expectations.

There is increasing evidence that elderly patients might benefit from avoiding exposure to GA as it is linked to an increase in the risk of cognitive dysfunction and metabolic derangements.¹⁸ For example, Balentine and his colleagues utilized the American College of Surgeons National Surgical Quality Improvement Project to compare the perioperative outcomes of elective inguinal hernia repair under local or GA in elderly patients.

They found that elective inguinal hernia repair under LA was associated with a reduction in postoperative complications in patients aged 75+ years (95% CI −0.11 to −1.13) as well as shortened operative time in patients <75 years.¹⁹ In addition, they projected national cost savings for greater use of LA, ranging from $9 million to $45 million annually.¹⁹

The American College of Surgeons and the American Geriatrics Society recommendations for the care of elderly encouraged surgeons from all subspecialities to identify procedures where avoidance of GA might be linked to improved perioperative outcomes.²⁰ While data on PCNL under LA are scarce, this comprehensive review highlights the feasibility and safety of PCNL under LA.

However, we failed to identify ideal candidates for PCNL under LA. This is due to lack of an explicit objective description of patients' comorbidities and stone complexity using validated scores such as the Charlson Comorbidity Index and Guy's stone score.^21,22 Moreover, the lack of data on stone complexity hindered our efforts to conduct a meaningful comparison of different perioperative outcomes and SFRs between different modalities of anesthesia used during PCNL.

Furthermore, the coronavirus disease 2019 pandemic has changed surgical practice in large parts of the world, with emphasis on shifting toward outpatient/ambulatory surgeries for different conditions.²² In concert with these changes, the burden of stone disease and cost of treatment is on the rise.²³ Therefore, there has been heightened interest in exploring the safety and feasibility of ambulatory PCNL to mitigate the cost of PCNL as well as increase patient access to this procedure.²²

While LA ureteroscopy has been well described, the use of LA as an alternative for GA in PCNL procedures might also help hasten the process of establishing the ambulatory PCNL pathway.¹⁷

Future directions

In this review, we found a few studies that examined the feasibility and outcomes of PCNL under LA. There is a need for clinical trials comparing the safety and effectiveness of PCNL under LA and other different regional anesthetic techniques that emphasize including enhanced recovery after surgery protocols as an integral part of the study design.

Moreover, these trials should report on stone complexity, perioperative comorbidity, and frailty using validated scores and tools.^24,25 In addition, efforts are needed to identify novel outcome measures such as patient mobility, functional recovery, and inflammatory biomarkers.

Future studies should focus on determining the proper dose and type of local anesthetic used in PCNL and identification of a suitable patient population for these procedures.

Footnotes

Authors' Contributions

M.S. was involved in article writing, data collection, and data interpretation. A.F. was involved in article writing and data collection. P.M. and S.P. were involved in article editing and project supervision. B.S. was involved in concept and design of the study, article editing, and project supervision.

Author Disclosure Statement

No competing financial interests exist.

Funding Information

No funding was received for this article.

Abbreviations Used

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