REVIEW

CURRENTOPINION Postpercutaneous nephrolithotomy bleeding:

aetiology and management

Copyright © Lippincott W

0963-0643 � 2014 Wolters Kluwer

Arvind P. Ganpule, Darshan H. Shah, and Mahesh R. Desai

Purpose of review

Postpercutaneous nephrolithotomy (PCNL) bleeding is the most dreaded complication following PCNL. Inthis article, we refer to risk factors contributing to post-PCNL bleeding and the criteria to decide the line ofmanagement in such cases. We further discuss the treatment algorithm for the management of thecomplication.

Recent findings

A perfect puncture is a ‘key’ to avoid post-PNL bleeding. Superselective angioembolization (SAE) is anefficacious and well tolerated method of controlling post-PCNL bleeding, and the success rate of SAE isfound to be greater than 80%. Pseudoaneurysm is the commonest finding of SAE, which is responsible forpost-PCNL bleeding. A recent study suggested that multiple percutaneous accesses, more than two bleedingsites identified during renal angiography, and the use of gelatine sponge alone as the embolic materialwere high-risk factors for the failure of SAE. A significant number of patients experience postinfarctionsyndrome in varying degree of severity after SAE.

Summary

Post-PCNL bleeding is a life-threatening complication. Most of the post-PCNL bleeds subside withconservative management, and SAE is an effective means of controlling post-PCNL bleeding. A skilledinterventionist can achieve successful control of bleeding with a variety of agents available. Multiplepunctures and evidence of more than two lesions predict high risk of failure of SAE.

Keywords

bleeding, embolization, percutaneous nephrolithotomy

Department of Urology, Muljibhai Patel Urological Hospital, Nadiad,

INTRODUCTION

Percutaneous nephrolithotomy (PCNL) for renalcalculi was first described by Fernstrom and Johans-son [1]. The complications of PCNL include fever,infection, and late complications, such as infundib-ular stenosis. The most dreaded one is bleeding thatoccurs in 14–24% of patients [2]. Simple supportivecare and transfusion control most episodes of bleed-ing. However in 0.8% of cases, surgical interventionwith angiographic embolization or open explora-tion is required [3]. The drop in haemoglobin levelmay exceed 2.1 mg% [4].

The key points in management of post-PCNLbleeding are as follows:

Gujarat, India

Correspondence to Dr Mahesh R. Desai, Medical Director, Muljibhai

(1)

Patel Urological Hospital, Dr Virendra Desai Road, Nadiad 387001,

Which patients are most prone to developthese problems?

Kheda, Gujarat, India. Tel: +91 2682520323; fax: +91 2682520248;

(2) e-mail: mrdesai@mpuh.org

Curr Opin Urol 2014, 24:189–194

DOI:10.1097/MOU.0000000000000025

What should be the criteria to decide whichsubset of patients would benefit from conserva-tive treatment and who benefit from aggressivesurgical management?

illiams & Wilkins. Unau

Health | Lippincott Williams & Wilk

(3)

tho

ins

What is the preoperative imaging modality ofchoice to decide the line of management?

In this article, we discuss the aetipathology andmanagement of post-PCNL bleeding.

Aetipathology of postpercutaneousnephrolithotomy bleeding

Bleeding after PCNL occurs as a result of eithertraumatized renal parenchyma or injury to the peri-nephric vessels [5]. Bleeding can also occur during

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KEY POINTS

� Most of the post-PCNL bleeds subside withconservative management.

� Superselective angioembolization (SAE) is an effectivemeans of controlling post-PCNL bleeding.

� Multiple punctures and evidence of more than twolesions predict high risk of failure of SAE.

Urolithiasis

needle puncture, tract dilatation, intraoperativeinstrument manipulation, or in the postoperativeperiod [6]. Renal vessel damage with subsequentdevelopment of arteriovenous fistulas or pseudo-aneurysms is a well known source of bleeding afterPCNL. Arteriovenous fistulas and pseudoaneurysmsof the renal arteries are formed by a high-pressureleak from a lacerated artery, which is transmittedthrough the tract into a lower-resistance system,such as a vein or a connective tissue space [7].PCNL-related bleeding is believed to be the resultof injury to either the anterior or the posteriorsegmental arteries rather than the smaller peripheralinterlobular arteries, which are surrounded by denseparenchyma and therefore easier to tamponade withthe nephrostomy tube [3].

A transparenchymal posterolateral puncture of amiddle or lower pole calyx is the safest place becausethe puncture is most likely to pass through the areaof Brodel’s avascular line.

Factors associated with postpercutaneousnephrolithotomy bleeding

The predictive factors for post-PCNL bleeding can beeither preoperative or intraoperative.

Preoperative factor

Various multivariate analysis have correlated theassociation of patient age, sex, BMI, the presenceof comorbidities, such as hypertension, diabetesmellitus, serum creatinine level, history of priorrenal surgery and the type of the stone, stoneburden, the degree of hydronephrosis, and the sur-geon’s experience [8].

Patients with arteriosclerosis of the renal arterybranches accelerated by ageing, hypertension, ordiabetes are at a higher risk for post-PCNL haemor-rhage. Arteriosclerosis may impair the self-healingproperties of the arterial wall because of the loss ofits normal muscle and elastic layers [9]. The presenceof infection also prevents the formation of bloodclot. Infections are also responsible for secondaryhaemorrhage.

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Operative factors

Data suggest that patient age, American Society ofAnesthesiology (ASA) grade, stone burden, andoperative duration are associated with an increasedrisk of vascular complication. It is postulated thatthe treatment of large stone burdens with multiplepunctures is associated with greater blood loss.Although extremely variable figures of between3 and 46% have been reported, Martin and cow-orkers [10–14] documented a 28% increase in theincidence of bleeding when the number of punctu-res rose above two. In a similar study, the authorsnoted that operation time was a risk factor for bothseptic shock and severe haemorrhage. The patientswithout hydronephrosis before operation weremore likely to suffer severe renal bleeding. Reducingintraoperative puncture time can reduce the pro-bability of severe post-PCNL haemorrhage. The useof a comparatively large nephroscope passage waslikely to result in severe renal bleeding [15

&&

].In one study, significant risk factors for severe

bleeding were upper caliceal puncture, solitarykidney, staghorn stone, multiple punctures, andinexperienced surgeon [16].

MANAGEMENT OF POSTPERCUTANEOUSNEPHROLITHOTOMY BLEEDING

The management of post-PCNL bleeding can beclassified as follows:

(1)

riz

Conservative management

(2) Endovascular treatment of post-PCNL bleeding (3) Surgical management.

Parameters that help in deciding the line ofmanagement are as follows:

(1)

Complete blood count:The comparison of haematocrit levels (preoper-ative and postoperative) helps in assessing theseverity of blood loss. Similarly, if there is ahistory of blood transfusion one should assessthe serum calcium levels and the bleedingparameters. Haematocrit is a better indicatorof postoperative blood loss than haemo-globin levels.

(2)

Imaging:(a) Colour Doppler ultrasound has the

advantage of diagnosing the cause of bleed-ing at the bedside; however, this is fraughtwith limitations of being subjective andhaving intraobserver and interobserver vari-ations. A simultaneously done greyscaleultrasound will also report the loculatedor generalized collection of residual calculi.

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FIGU

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Postpercutaneous nephrolithotomy bleeding Ganpule et al.

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(b) Computed tomography (CT) imaging:

pyri

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[18]

-064

The application of contrast CT for diagnosingthe cause of bleeding has been well described ingastrointestinal bleeding. The bleeding can beprecipitated by drugs such as papavarine. Thereis limited literature available on the applicationof this imaging modality in the management ofpost-PCNL bleeding.

Since the past year at our institute, we have beendeploying this imaging modality in the algorithmfor the management of post-PCNL bleeding. Com-parative studies are underway to assess the out-come.

The perceived advantages of CT angiographyinclude the following:

(1)

Noninvasive nature (2) Ability to identify the exact site of bleeding (3) The CT angiogram may act as a ‘road map’ for

the interventionalist to plan the intervention[17

&

].

MANAGEMENT

Bleeding after PCNL is a stressful situation for thepatient and the operating surgeon alike. The algor-ithm for the management of bleeding after PCNL isdescribed (Fig. 1) [18].

ght © Lippincott Williams & Wilkins. Unau

Life-threatening bleeding a

Conservative management (bed rest, crystallo

Assess haemodynamic

Stable haemodynamically

SelecContinue conservative treatment

Bleeding stops – continue same managem

If absolute indications – proceeds with

1. Algorithm for the management of postpercutaneous n.

3 � 2014 Wolters Kluwer Health | Lippincott Williams & Wilk

Conservative treatment

The management options depend upon whether thebleeding is arterial or venous. Venous haemorrhageis usually managed conservatively. The manage-ment depends on the time of presentation, namelyintraoperative, immediate postoperative, or delayedpostoperative.

Intraoperative

A perfect puncture is defined as a short, straight tractfrom the skin, subcutaneous tissue through the cupof calyx into the desired calyx. It generally avoidsinjury to anterior or posterior segmental branches. Ifthe puncture is not an end-on puncture, it is likely tobleed, which manifests as hypotension and tachy-cardia (suggestive of arterial bleeding). The surgeonmay also experience difficulty in intraopertaivevisualization of the stone. In such cases, the surgeonshould opt for placing a nephrostomy tube and stagethe procedure. A close watch on the vital signs isessential in such cases. The nephrostomy tube helpsin arresting the bleeding in the pelvicalyceal systemby the formation of clot and stops the bleeding inthe tract by tamponade. A stitch, which secures thenephrostomy, should be placed posterior to the siteof entry of the nephrostomy in the pelvicalycealsystem. A typical way of arresting an immediatepostoperative bleed from the tract is tamponadewith the help of the fists of two hands, one placed

thorized reproduction of this article is prohibited.

fter PCNL

ids, haemostatic drugs, etc.)

stability

Unstable haemodynamically

tive or superselective angioembolization

ent

angioembolization

ephrolithotomy (PCNL) bleeding. Reproduced with permission

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FIGURE 2. Method of compression following tubelesspostpercutaneous nephrolithotomy.

Urolithiasis

over the back and the other over the abdomen(Fig. 2). This is particularly useful if a tubelessapproach is employed.

USE OF HAEMOSTATIC AGENTS

Kumar et al. [19&

] used tranexamic acid in patientsundergoing PCNL. They concluded that it is welltolerated and associated with reduced blood loss andcomplication rate. They administered 1 g tranexa-mic acid followed by three oral doses of 500 mg in24 h. Mean haemoglobin drop was significantlylower in tranexamic acid group (1.39 vs. 2.31 g/dl,P<0.0001). Blood transfusion rate was lower in thetranexamic acid group (2 vs. 11%, P¼0.0180). Cau-terization of PCNL track at the end of procedure mayreduce the chances of bleeding [20].

There are various other locally applied haemo-static agents described in the literature. These all aimto reduce the track-site bleeding.

TachoSil is a sterile equine collagen matrixcoated with human fibrinogen, human thrombin,and fibrin glue. Studies showed that TachoSil-sealedtubeless PCNL significantly decreased urinary leak-age rate and perirenal haematoma rate. However,the decrease in perirenal haematoma formation wasnot statistically significant.

Various other studies used absorbable porcinegelatine sponge of fibrin (Spongostan), oxidizedcellulose (Surgicel), and bovine collagen granules(Floseal) for this purpose but did not achieve sig-nificance level. However, they significantly reducedanalgesic requirements [21,22].

Immediate postoperative

The colour of output from the nephrostomy isan indicator of the severity of bleeding from thekidney. The nephrostomy should be kept clamped

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for at least 6 h after insertion to ensure adequatehaemostasis if the surgeon suspects bleeding. At ourcentre, we declamp the nephrostomy after 6 h ifthe return from the urethral catheter is clear. Thisindicates that there is no bleed from the pelvicaly-ceal system.

Selective angioembolization and otheroptions

The absolute indications for angioembolization areas follows [18]:

(1)

riz

Haemodynamic instability due to life-threaten-ing bleeding

(2)

Repeated clot evacuations (3) Repeated blood transfusions (4) Renal Doppler showing vascular lesions (5) Continuing haemoglobin and haematocrit drop.

TECHNIQUE OF ANGIOEMBOLIZATION

The personnel performing angioembolizationvaries; at our centre it is performed by an interven-tional nephrologist specialized in endovascularinterventions. Angioembolization is usually doneby an interventional radiologist [23

&&

].

Access for vascular intervention

The access can be gained either through the ipsilat-eral femoral route or through the brachial approach.The choice of access depends on the preference ofthe interventionalist and the presence and absenceof peripheral vascular disease. The catheter is selec-tively advanced into ‘appropriate’ segmental renalartery; this is determined by flush arteriogram lat-eral and oblique views that are magnified. Thesehelp in exactly delineating the site of injury. The‘road map’ functions available on digital subtractionangiogram help in ascertaining the exact site ofbleed. The size and the number of embolic materialto be used depend on the site and size of the lesion.Once the coil is deployed the successful deploymentof coil is confirmed with intermittent angiograms.This step helps in embolization of the appropriateartery and inadvertent migration of the coil. Thevarious agents used for embolization are as follows:

(1)

Metallic coils alone (2) Gelatine sponge alone (3) Gelatine sponge and metallic coils (4) Gelatine sponge with autologous blood.

In the experience of Jain et al. [18], the com-monest embolization material used was gelatinesponge with metallic coils. When it is possible to

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Postpercutaneous nephrolithotomy bleeding Ganpule et al.

embolize a tertiary or quaternary branch of the renalartery it is called as SAE; if the main branch needs tobe embolized it is termed ‘complete embolization’.The aim of any endovascular intervention for post-PCNL bleeding is to achieve SAE.

Outcome and findings of superselectiveangioembolization

The success of SAE has been described as the arrestof bleeding by blocking the offending vessel andmaintaining normal vascularity to the surroundingnormal kidney [22]. The success rates exceed 80% inmost of the series [18,23

&&

]. In the series by Somaniet al. [24], SAE failed in one case requiring emer-gency nephrectomy. The histopathology sub-sequently showed renal cell carcinoma. A similarcase is reported by Richstone et al. [23

&&

], whereinafter nephrectomy the authors report the presenceof urothelial carcinoma. These cases highlight thefact that the treating physician should be aware thatthere can be a chance that a tumour is missed, whichmay be the cause for bleeding.

Angiographic findings

Richstone et al. [23&&

] reported pseudoaneurysm asthe commonest finding in 53% of the patients; thiswas followed by lacerated renal vessels and arterio-venous malformations. In their series, Richstonefound that in three patients, they could not noticeany abnormal angiographic findings. Interestingly,they noticed that the negative angiographic find-ings came down from 12 to 3.5%, suggesting alearning curve in performing and interpretingangiographic findings. Jain et al. [18] also foundarteriovenous fistula to be marginally commonerthan pseudoaneurysm (43.9 vs. 41.5%). Jain et al.[18] noted that among the common bleeding sitesidentified the commonest was lower pole (48.6%),followed by the upper pole (31.4%) and last themidpole (7%). In a series by El-Nahas et al. [16],upper pole calyx puncture was associated with ahigher incidence of vascular injury. The possiblereason put forth by the authors was the possibilitythat an oblique longer tract was used resulting intorque and resultant bleeding. It was also speculatedthat a tract through the thick parenchyma increasesthe possibility of bleeding and resultant vascularinjury.

In our opinion, the site of bleeding dependson the preference or choice of the surgeon to gainaccess. At our institute, the calyx of choice to gainaccess was the lower pole calyx and hence theincidence of vascular injury was skewed to thelower calyx.

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Risk factors predicting the outcome ofsuperselective embolization

A recent study suggested that multiple percutaneousaccesses, more than two bleeding sites identifiedduring renal angiography, and the use of gelatinesponge alone as the embolic material were high-riskfactors for the failure of SAE [25]. In the study byJain et al. [18], among the total 41 patients studied,35 patients (85.3%) underwent successful emboliza-tion. Among these six patients, two subsequentlyunderwent nephrectomy. The authors performed areview of these two patients; both patients had alarge bulk of stone (staghorn calculi) and more thanthree punctures. Thus, the authors suggest that largestone bulk and multiple punctures are predictors ofthe failure of angioembolization, concurring withthe findings of the recent study by Zeng et al.[18,25]. The second interesting finding noted byJain et al. [18] was that both these patients had acomparatively larger arteriovenous malformation(6 vs. 3.7 mm in others). According to Richstoneet al. [23

&&

] in approximately 5–7% of patients nodemonstrable angiographic findings were seen.

COMPLICATIONS OF SUPERSELECTIVEEMBOLIZATION

The complications of SAE include postembolizationsyndrome, coil migration, and risk of renal deteriora-tion.

Postembolization syndrome

This has been described as flank pain and raisedwhite blood cell count with nausea and vomiting[26]. Ninety percent of the patients experience thissyndrome in varying degree of severity. Jain et al.[18], in their series, noticed an infarction syndromein 63.4% but could not find any correlation to thematerial used for embolization. Somani et al. [24]described this syndrome in 50% of their cases. Themost common symptom of concern for the patientis severe pain, which has an onset within an hour ofembolization and may at times also require narcoticanalgesics.

Coil migration

A potential serious complication of SAE is coilmigration either into an undesired location or intoan extranatomic site. The migration into peripheralcirculation and the lungs has been reported [27]. Itcommonly presented after 1 year; however, in thecase by Bhageria et al., it presented within 3 monthswith renal colic. Bhageria et al. [28] reported coilmigration into the urinary tract, which caused

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Urolithiasis

urinary obstruction. Possible mechanisms for thiscoil migration are as follows: (1) the fistulous com-munication had a larger size than the embolizationcoil; (2) the artriocalyceal communication becamelarger over a period resulting in migration; and (3) arupture could have occurred in the pseudoaneur-ysm. The authors feel that the second mechanismwas more likely for the occurrence of migration [28].

Postinfarction renal function

The concern of postinfarction deterioration of renalfunction had been addressed by El-Nahas et al. Theynoted that DMSA renograms post SAE did not revealany photopenic areas in 20% of cases who under-went SAE and the DMSA uptake increased statisti-cally in these renal units. The findings suggest thatSAE, if selectively blocks the offending artery, isrenoprotective [29].

CONCLUSION

Post-PCNL bleeding is a life-threatening compli-cation. Most of post-PCNL bleeds subside with con-servative management. SAE is an effective means ofcontrolling post-PCNL bleeding. A skilled interven-tionist can achieve successful control of bleedingwith a variety of agents available, which include gelfoam and coils. Multiple punctures and evidence ofmore than two lesions predict high risk of failureof SAE.

Acknowledgements

None.

Conflicts of interest

There are no conflicts of interest.

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& of special interest&& of outstanding interest

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3. Kessaris DN, Bellman GC, Pardalidis NP, Smith AG. Management of hemor-rhage after percutaneous renal surgery. J Urol 1995; 153:604–608.

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22. Singh I, Saran RN, Jain M. Does sealing of the tract with absorbable gelatine(Spongostan) facilitate tubeless PCNL? A prospective study? J Endourol2008; 22:2485–2493.

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Richstone L, Reggio E, Ost MC, et al. Hemorrhage following percutaneousrenal surgery’ characterization of angiographic findings. J Endourol 2008;22:1129–1135.

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25. Zeng G, Zhao Z, Wan S, et al. Failure of initial renal arterial embolization forsevere post-percutaneous nephrolithotomy hemorrhage: a multicenter studyof risk factors. J Urol 2013; 190:2133–2138.

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29. El-Nahas AR, Shokeir AA, Mohsen T, et al. Functional and morphologicaleffects of postpercutaneous nephrolithotomy superselective renal angio-graphic embolization. Urology 2008; 71:408–412.

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