Case series – Liver injury during percutaneous nephrolithotomy

INTRODUCTION

Although percutaneous nephrolithotomy (PCNL) remains gold-standard treatment for large renal stones, there exists minimal reports describing management of liver injury during PCNL.^1–3 Here, we present a multi-institutional series of cases of liver injury during PCNL.

Endourologists across four academic medical centers reviewed procedure logs identifying cases of liver injury during PCNL. The authors received institutional review board approval/exemption from their respective institutions.

From January 1, 2017, to December 31, 2020, three cases of liver injury during PCNL were identified from a total of 1213 cases reviewed (0.25%).

CASE SERIES

Case 1

A 49-year-old female presented with computed tomography (CT) imaging demonstrating 2.4 cm of nephrolithiasis in right renal pelvis (liver unremarkable). She underwent PCNL in modified Galdako-Valdivia positioning with (subcostal) renal access obtained using endoscopic guidance combined with ultrasonography (US) and fluoroscopy. Rigid and flexible nephroscopy (with ultrasonic-lithotripsy and endo-basketing) were used to remove stones prior to placing a 5 Fr nephro-ureteral catheter. Operative time was 120 minutes with <100 mL estimated blood loss (EBL). At PCNL conclusion, the patient appeared free of stone/complications.

On postoperative-day (POD ) 1, the patient’s physical evaluation was unremarkable. Labs demonstrated hemoglobin (Hgb) of 10 g/dL (from 12.4 g/dL pre-operatively) and normal serum creatinine (SCr). She was discharged home POD1. Routine outpatient CT revealed the nephrostomy tube (NT ) traversing the liver (Figure 1) and the patient was readmitted. Except for Hgb of 7.7 g/dL, she remained clinically unremarkable for two days (during which the NT tube was removed). At six-week followup, the patient appeared well, with a CT demonstrating a resolving hematoma (Figure 1).

Figure 1.

Representative computed tomography scan images depicting nephrostomy tube traversing inferior caudate lobe of liver associated with hematoma.

Case 2

A 53-year-old female presented with CT imaging demonstrating bilateral nephrolithiasis, including a 2.2 cm right proximal ureterolith (liver unremarkable) (Figure 2A). The patient underwent right PCNL (prone positioning). Renal access was obtained via fluoroscopic bullseye technique (Figure 2B). Partial urinary tract duplication (to mid-right ureter) necessitated additional percutaneous access to the lower moiety. Nephroliths were removed using endo-graspers and ultrasonic impact lithotripter. A 14 Fr pigtail nephro-ureteral catheter was placed alongside an 8 Fr variable-length Jureteral stent. Operative time was 150 minutes, with 200 mL EBL. At PCNL conclusion, the patient appeared free of stone/complications.

Figure 2A.

Representative images from preoperative computed tomography scan 2.2 cm right obstructing proximal stone and smaller non-obstructing right kidney stones.

Figure 2B.

Representative intraoperative images depicting access sheath (left) and nephrostogram showing duplication (right).

On POD1, her physical evaluation was unremarkable. Routine CT imaging from POD1 revealed the nephro-ureteral catheter traversing 4 cm of the liver (Figure 2C). Labs revealed Hgb of 9.9 g/dL (from 11g/dL), with SCr of 0.6 mg/dL. The patient remained inpatient for PCN removal by interventional radiology (IR ) on POD4; discharge home occurred POD5. At outpatient followup (POD6), she appeared well, with resolving liver injury observed on repeat CT.

Figure 2C.

Representative postoperative images depicting nephrostomy tube going through the liver (first and second) and resolving liver injury after removal of nephrostomy tube on postoperative day 4 (third image).

Case 3

A 68-year-old male with horseshoe kidney presented for definitive treatment of right moiety nephrolithiasis (following 15 shockwave lithotripsy procedures). CT imaging revealed bilateral moiety nephrolithiasis, including a 5.9 × 2.8 cm nephrolith filling the middle- and lower-third of the right renal moiety (Figure 3A). CT also displayed two <3 cm liver cysts without hepatomegaly. The patient underwent a pre-PCNL NT placement (right moiety) by IR using fluoroscopic guidance (Figure 3B). The patient underwent a (prone) PCNL, accessing the kidney through indwelling NT. The nephrolith was fragmented/basketed. A 10 Fr NT was placed in the collecting system with an open-ended 5 Fr catheter extending from the ureter through flank incision. Operative time was 119 minutes, with 100 mL EBL. At PCNL conclusion, the patient appeared free of stone/complications.

Figure 3A.

Representative images from preoperative computed tomography scan depicting horseshoe kidney with a 5.9 × 2.8 cm complex shaped staghorn calculus in the right renal moiety and 1.5 × 1.0 cm stone burden in the lower third of the left renal moiety.

Figure 3B.

Representative images from preoperative interventional radiology placement of nephrostomy tube into right renal moiety.

On POD1, his physical evaluation was unremarkable. Routine CT imaging on POD1 revealed residual nephroliths and the percutaneous NT tract passing through the caudal tip of a posterior hepatic lobe, with trace amount of surrounding hemorrhage (Figure 3C). Hgb was 12.9 g/dL and SCr was 1.1 mg/dL. He was discharged on POD1 (with NT and open-ended catheter in place). On POD5, a repeat PCNL was performed using a flexible cystoscope to inspect the existing PCNL tract (without further dilation or sheath placement) and to retrieve the two residual nephroliths. The patient was left with a 10 Fr NT and open-ended ureteral catheter. On POD7, CT imaging and an antegrade nephrostogram were obtained, noting elimination of nephroliths, as well as antegrade drainage of contrast (all drains/catheters were then removed). Followup imaging demonstrated subsequent resolution of liver injury, without residual stone burden.

Figure 3C.

Representative images from postoperative computed tomography scan depicting percutaneous nephrostomy tube tract passing through the caudal tip of the posterior segment of right hepatic lobe with trace hemorrhage adjacent to the tubes, liver, and the right kidney.

DISCUSSION

Adjacent organ damage or violation of the pleura space are potential risks during PCNL. Known risk factors for liver injury include hepatomegaly and supracostal access during surgery.⁴

In addition to our series, we identified only three prior case studies published in peer-reviewed literature.

In the first report, the patient underwent a right PCNL (supracostal fluoroscopic access) for multiple upper pole nephroliths.¹ Postoperatively, the patient developed abdominal pain and gross hematuria through the NT. The NT was immediately capped, and the patient underwent resuscitation, including IV hemostatic agents (ethamyslate 250 mg every six hours and tranexamic acid 500 mg every 12 hours) and one unit of red blood cells. CT imaging demonstrated a 6 × 5 cm intrahepatic fluid collection and the NT traversing the inferior edge of the right hepatic lobe. On POD3, the NT was removed under fluoroscopy, with concurrent instillation of fibrin sealant across the liver parenchyma. The patient was discharged on POD5.

The second report involved a patient with a 2.2 cm stone in the lower pole of the right kidney.² On POD1 from PCNL, the patient developed right shoulder pain, with erythema noted around the nephroureteral catheter. CT imaging demonstrated a small, perihepatic free fluid collection. The patient became febrile POD2, with an elevated white blood cell (WBC) count of 17.7 × 10³/mL. The patient defervesced by POD4 while receiving antibiotic therapy and supportive care. CT imaging demonstrated a 19 × 5.8 cm right subhepatic fluid collection; however, vital signs were unremarkable and Hgb was stable at 10 mg/dL, thus the patient was discharged home. As an outpatient on POD7, interval CT imaging obtained for shortness of breath noted the persistent hepatic fluid collection. The fluid, drained by IR, had a bilirubin level consistent with bile. Endoscopic retrograde cholangiopancreatography allowed for placement of biliary stents and the patient was discharged on POD12. Repeat CT imaging one month later noted resolution of the fluid collection.

The third reviewed publication documented two patients with liver injury after PCNL.³ One patient underwent PCNL for 1.4 cm nephrolith accessed via upper pole posterior calyx. The second patient presented large nephroliths in the bilateral moieties of horseshoe kidney. In both cases, liver injury was incidentally detected on routine postoperative CT imaging. Neither patient exhibited excessive abdominal pain, abnormal laboratories, or hemodynamic concerns postoperatively. Both patients were managed with supportive treatment and delayed removal of NT on POD13 and POD7, respectively.

While patient positioning seems to play a role in PCNL-associated injuries, access location (supracostal) may present the greatest risk of liver injury, considering a review of CT scans suggesting that access obtained at/above the 11th rib during respiratory expiration have 14% risk of liver injury.^5,6 Although efforts are now made to standardize operative reports, the precise location of access in our case series was not clear for two of the liver injuries — limiting our ability to infer risk. Furthermore, US offers a means for real-time viewing of the access needle and adjacent organs during renal puncture, potentially reducing liver injury.⁷ Ng et al compared 184 PCNL patients, noting that while stone-free rate remained similar between fluoroscopy and US cohorts, the only organ injury occurred in the fluoroscopy cohort.⁷

Rassweiler-Seyfried et al reviewed PCNL renal access methods, considering safety/efficacy of novel techniques, such as electromagnetic tracking and real-time 3-D renal reconstruction.⁸

Overall, due to the uncommon nature of liver injury during PCNL, it is difficult to fully understand the risk factors. The primary lesson learned from our review appears to be that PCNL-related liver injuries may be managed non-operatively.

CONCLUSIONS

This series, and existing literature, suggest that liver injury during PCNL is uncommon and, although includes risk for severe bleeding, can generally be managed with observation/supportive care.

KEY MESSAGES.

• ■ Liver injury during PCNL is uncommon but does occur.

• ■ Liver injury secondary instrumentation during PCNL can generally be managed with observation and supportive care.