Tackling the Percutaneous Nephrolithotomy

Amy E. Krambeck, M.D. Associate Professor of Urology

Mayo Clinic Rochester, Minnesota

Outline

• Indications • Preoperative considerations • Challenges • Complications • Review of technical aspects

• Access • Equipment • Exit strategies

Indications for PCNL

• Stone volume/ staghorn • Stone location • Stone composition (struvite, cystine) • Renal anomalies • Distal obstruction (UPJ, stricture) • Failure of other modality • Patient comorbidities

Treatment Considerations Upper Urinary Tract Calculi

• Ureteral access concerns • Neobladder • Ureteral reimplantation • Bladder neck closure

• Surgeon experience • Ureteroscopy, PCNL, SWL

• Likelihood of rendering stone free

Treatment Decision by Stone Burden

• Stone Burden • Most important factor in determining

treatment modality outcome Stone Burden

Stone Free Rate

Ancillary Procedures Retreatment

Case Volume and Stone Free Rate

•HVol = >77 cases •LVol = <77 cases

•HVol SF 82.5% •LVol SF 75.1%

•120 cases/year

Opondo D, et al. Eur Urol 62:1181-7; 2012

Contemporary PCNL Evaluation of 1585 Procedures

• Medical co-morbidities in 48.8% • Simultaneous bilateral PNL in 6.3% • Access by the urologist

• LC 66.4%, MC 19.2%, UC 14.4% • Multiple access in 8%

Duvdevani, Denstedt et al. J Endo 21:824-829, 2007

Stone-Free Results

• KUB postoperative and 3 months • 89.1% at discharge • 94.8% at 3 months

• 24.7% required 2nd procedure • 342 2nd nephroscopy • 29 SWL • 20 ureteroscopy

Duvdevani, Denstedt et al. J Endo 21:824-829, 2007

Stone-Free Rates

Surface Area (mm2)

% Stone Free (by KUB)

1-500 97.9

501-1000 94.6

1001-1500 92.9

>1500 88.6

Duvdevani, Denstedt et al. J Endo 21:824-829, 2007

Length of Hospitalization

• Mean 4.0 days (range 1-30 days)

• Length of stay decreased over time • 6 to 3 days

Duvdevani, Denstedt et al. J Endo 21:824-829, 2007

Percutaneous Nephrolithotomy for Staghorn Calculi: A Single

Center’s Experience over 15 Years

Soucy F, Ko R, Duvdevani M, Nott L, Denstedt J, Razvi H. J Endourol 23:1669-73; 2009

Staghorn Stone Free Results

• 509 partial or complete staghorns • 84% single access tract • 9% secondary PCNL • Stone-free rates (varied imaging)

• 78% discharge • 9% at 3 months

• Transfusion rate 0.8%

Soucy F et al, J Endo 23:1669-73;2009

Developments in Technique and Technology: The Effect on the Results of

Percutaneous Nephrolithotomy for Staghorn Calculi

Desai M, Jain P, Ganpule A, Sabnis R, Patel S, Shrivastav P. BJU International 104: 542-8; 2009

Staghorn Stone Free Results • Largest PCNL staghorn series

• 834 procedures in 773 patients • Evaluated outcomes over 17 years • Time, experience and technology reduced:

• Operative and hospital duration • Tract number • Reintervention • Complications • Residual calculi

• Overall stone free 86%

Desai M et al, BJU Int 104:542-548; 2009

AUA Guidelines on Management of Staghorn Calculi

• PCNL should be the 1st treatment

• If combo (i.e. sandwich) therapy PCNL should be last procedure

• SWL should not be used

• Open surgery should not be used

Morbid Obesity • Limited options

• SWL & PCNL

• Comorbidities increase stone formation

• HTN, DM

• Increased excretion calcium, oxalate, sodium, uric acid

Skin to stone distance?

PCNL in the Obese Technical Challenges

• Anesthesia and prone positioning • Total lung & functional residual capacity reduced • IVC compression reduces preload & oxygenation

• Strategies to reduce

• Lateral or supine position1

• Conscious sedation/local anesthesia2

• Awake intubation/prone patient self positioning3

1. Gofrit O et al, J Endourol 16:383-6; 2002 2. Kanaroglou A et al, Can J Urol 13: 3153-5; 2006 3. Wu S, et al, J Endourol 23: 1599-602; 2009

PCNL in the Obese Technical Challenges

• Skin to stone distance • Skin cut down – larger incision • Extra long access sheath with

flexible scope •Sequential dilation

• Upper pole access

The Clinical Research Office of the Endourological Society Percutaneous Global Study: The Influence of Body

Mass Index on Outcomes

Fuller A, Razvi H, Denstedt JD, Nott L, Pearle M, Cauda F, Bolton D, Celia A, de la

Rosette J. J Urol 188: 138-144; 2012

PCNL Outcomes Based on BMI

• 3709 patients from 96 centers CROES • Obesity associated with

• Longer OR duration • Higher retreatment rates • Lower stone free rates • Greater comorbidities

• No difference in • Hospital stay • Complications • Transfusion

Fuller A, et al. J Urol 188: 138-144; 2012

Age and PCNL

• Matched • Stone # • Size • Location • Imaging

>70 <70 P-value N 334 334 Age 74.7 46.9 <0.001 eGFR 66.4 84.6 <0.001 Transfusion 6.0 3.0 0.099 SF 78.7 81.7 0.381 LOS 5.0 4.4 0.288 Postop eGFR 60.1 78.3 <0.001 Complication 19.9 6.6 <0.001

•HV center elderly longer LOS •3.9 vs 3.5 p=0.002

Okeke Z, et al. J Endourol 2012; 26: 996-1001

Anticoagulated or Coagulopathic Patients

• Condition must be corrected preoperatively

• If not possible consider ureteroscopic stone extraction

• 27 PCNL patients1 • Stone free rate 93% • 2 (7%) significant bleeding • 1 (4%) thromboembolic event

1. Kefer JC, et al. J Urol 2009; 181: 144-148

Renal Anatomy Stone Disease

• UPJ obstruction • Horseshoe kidney • Ectopic/fusion abnormalities • Calyceal diverticulum • Lower pole calyx • Urinary diversion

Horseshoe Kidney

• 1 in 400 individuals • Isthmus prevents ascent

resulting in malrotation • 60% may form stones • URS and SWL decrease

SF results

Yohannes P and Smith AD, J Urol 168: 5-8; 2002

Horseshoe Kidney-Technique • Abnormal calyceal orientation • Aberrant vasculature &

adjacent organs • Upper pole access

• Access to upper/lower calyces, pelvis, UPJ

• 60 procedures in 47 patients • Technical difficulties

• Lower calyceal and isthmus stones • Anteromedial calyces – consider

laparoscopic approach • Must have all modalities available to

maximize likelihood of success • Overall SFR 88%

• High rate of re-intervention • Single procedure in 30% of staghorns

Symons et al, BJU International 102: 1676-80; 2008

Urolithiasis in the Horseshoe Kidney: A Single Centre Experience

Urinary Diversion

• Increase risk of stones • 11% within 3 years

• Multifactorial • Chronic UTI • Urinary stasis • Foreign body • Hyperchloremic

acidosis • Urinary ammonium

absorption

Neobladder

Ileal Conduit

33 PCNL procedures Urinary diversion associated with

• Radiologist access (40% vs 0%, p<0.001) • 2nd look nephroscopy (36% vs 16%, p=0.046) • Struvite stones (80% vs 12.5%, p=0.006) • Post-operative sepsis (8% vs 0%, p=0.038)

No significant difference in

• Stone free rates • Complications • Transfusion rates • Length of hospital stay

Fernandez A, et al. J Endourol, October 25: 1615-1618; 2011

Percutaneous Nephrolithotripsy in Patients with Urinary Diversions A Case-Control Comparison of

Perioperative Outcomes

Francisco Sampaio & Renan Uflacker: Renal Anatomy Applied to Urology, Endourology and Interventional Radiology 1993

Intrarenal Anatomy

Lower Pole Calculi Stone-Free Rates by Stone Size

Lower Pole Study Group, J Urol 66:2082, 2001

% Stone Free

0102030405060708090

100

PCNL

SWL

100

63

93

23

86

14

< 10 mm 11 - 20 mm > 20 mm

p=0.003 p=0.001 p=0.029

Management of Lower Pole Calculi • < 1 cm

• Observation, SWL, ureteroscopy • 1-2 cm

• PCNL best • Ureteroscopy in select patients

• > 2 cm • PCNL

• Body habitus, anatomy, cost and patient preference must be considered

Raman J and Pearle M, Curr Opin Urol 18:214-9; 2008

Complications

Potential Complications • SIRS up to 23%

• Urosepsis 0.3-4.7% • Transfusion rate 0.8%-30.9%

• Intervention 0.6-1.4% • Pleural injury 0-3.1% • Organ injury 0.2-0.8%

• Colon injury 0.06% • Fluid over load – unusual with sheath • Death 0.12%

Rao, Preminger, Kavanagh Urinary Tract Stone Disease 2011 Duvdevani, Denstedt et al. J Endo 21:824-829, 2007

Blood Transfusion & Embolization

• 547 PCNL patients • 21 (3.8%) blood transfusion • 5 (0.9%) embolization, 1 nephrectomy • Risk factors

• Increasing age (60 vs 55) • OR time (119 min vs. 103) • Preop UTI (23.8% vs. 16.1%)

Keoghane SR, et al. BJU Int 2013; 111:628-632

CROES Study: Hemorrhage Rates

• 5803 patients • Transfusion rate 5.7%1

• ASA scores • Stone burden • Operative duration

• 0% in solitary kidneys • 5% anomalous kidneys

1. Lopes T, et al. J Endourol 25:755-762; 2011

Urologist Gained Access and AVF

• Study of 3338 PCNLs1 • IU Health & Mayo over 10 years

• 15 (0.48%) patients (16 kidneys) required angioembolization

• Time to bleed 7 days (1-15) • Transfusion required in 9 (60%) • No risk factors identified

1. El Tayeb MM, et al. Urology Pub Pending 2015

Supracostal Access: Puncture Site

16.7% of 5803 pts CROES

De la Rosette J, et al. J Endourol 2011; 25: 11-17

Supracostal Access and Pleural Injury

Author

Overall PNL

patient

No. of supracostal punctures

(%)

Overall pleural

complication (%)

Pleural complications

treated (%)

Stone free rate (%)

Young et al, Radiol 1985; 154:633

140 24 (17) 37 4.2 N/A

Picus et al, AJR 1986; 147:393

154 50 (32) 32 8 90

Fuchs and Forsythe, Urol Clin Am 1990; 17:99

344 106 (31) N/A 4.7 N/A

Narasimham et al, Acta Radiol 1991; 32:162

231 56 (24) 9 3.5 95

Lam et al, J Urol 1992; 148:1026-1029

91 25 (27)

28 2.2 N/A

Golijanin et al, J Endourol 1998; 12:403

320 104 (36) 8.7 4.3 87

Stening et al, J Endourol 1998; 12:359-362

N/A 21 None None 75

TOTAL 1280 386 (29) 16 3.8 92

Renal Function after PCNL • 87 PCNL patients followed 19.2 years1

• Vs. 288 SWL • Vs. 288 spontaneous passage

• New onset CKD • PCNL 9 (10.6%) • SWL 14 (5.2%) • SP 25 (8.7%)

• Risk CKD SF 5%2

P=0.09

1. Krambeck AE, et al J Urol 2008; 179: 2233-7 2. El-Zoghby ZM, et al Clin J Am Soc Nephrol 2012; 7: 1409-1415

Risk Factors for CKD Post PCNL

• 265 staghorn pts followed 12 months1 • CKD status:

• Stable 66.8% • Improved 12.8% • Declined 20.4%

• Immediate change in Cr postoperative only risk factor

1. Akman T, et al. J Urol 2012; 187: 1656-1661

Case Volume and Complications

• 120 cases/year

Opondo D, et al. Eur Urol 62:1181-7; 2012

Limiting Postoperative Complications

• Negative urine ctx1 • 162 - abx • Matched to + abx

• stone size • Comorbidities • Neph tube

• Other studies less SIRS with prophylactic antibiotics 1 week preoperatively2,3

Abx No abx P-value

Fever 2.5% 7.4% 0.04

SF 86.3% 74.4% 0.006

Retx 5.6% 11.8% 0.04

Comp 1.9% 22.0% <0.001

Clavian 1 2.5% 21% <0.001

>1 0 8.8%

1. Gravas S, et al. J Urol 188: 843-847; 2012 2. Mariappan P and Tolley DA et al. BJU Int 2006; 98: 1075-9 3. Bag S, et al Urology 2011; 77: 45

Technique

Pre-Operative Imaging

• CT Scan • Limit injury to

surrounding organs • Liver, spleen, colon,

lung • 1-2% retrorenal colon

• 25% scoliosis1 • IV contrast can be

beneficial

1. Onder H, et al. Surg Radiol Anat. 2014;36:67-70

• Placement of ureteral catheter

• C-arm fluoroscopy

• Precise calyceal puncture

• Safety wire as far into the urinary tract as possible

• Amplatz sheath - always

Access: General Principles

Operating Room Set-up

Separate imaging table with C-arm preferred

Under table x-ray source (reduces operator exposure)

Selection of Renal Access Site

• Most important factors - Stone location and burden

• Maximize stone removal via rigid scope

• Lower pole generally preferred

• decrease morbidity

Anesthesia Requirements

• General anesthesia preferred - Best airway protection when prone - Allows suspension of respiratory

excursions (end expiration)

• Local anesthesia is option1 - Adjunctive intravenous sedation - 8.3F anesthesia injection catheter - Delivers local anesthetic along tract

Grasso & Taylor Textbook of Endourology, 1997:99-113

Anesthesia Injection Catheter

8.3Fr

Fluoroscopically Guided Access

• Opacification of collecting system

• Ureteral catheter placed cystoscopically on side of stone

- 5F safety (open-ended) catheter - 7F ureteral occlusion balloon

catheter

• Prone position (flank inferior to post) • Arm on stone side on arm board (flexed

90°); opposite arm against patient • Pressure points padded

Patient Positioning

Other Patient Positions

• Supine • Lateral decubitus • Reverse lithotomy • Split-leg • Flexed-prone

Supine vs. Prone PCNL • Meta-analysis • 1,469 supine vs. 4,837 prone • No difference

• Stone-free rates (82.4 vs. 82.1%) • Bleeding • Colonic injury 0.5% • Pleural injury 0%

• Op times shorter supine--smaller stones

Wu P, et al. Int Urol Nephrol 43: 67-77, 2011

Principles of Access

• Posterior calyx to permit entry into collecting system

• Aim for calyx not infundibulum

• Avoid hemorrhage from interlobar artery

Accurate Calyceal Access

• Puncture site medial to posterior axillary line (avoids colon)

• Precise mid-calyx puncture required - Avoids peri-infundibular venous plexus

Anatomical Considerations Pleural Reflection

Supra-12th rib access is transthoracic but extrapleural

• 0/72 cases had hydro/pneumothorax

Supra-11th rib access is transthoracic & transpleural

• 5/26 (19%) incidence of hydro/pneumothorax

Insure sheath position Munver R, Delvecchio F, Newman G, Preminger G: J Urol 166:1242, 2001

Upper Pole Access • Often the optimal approach

- Staghorn stones - Large upper pole stone burden - Antegrade endopyelotomy - Proximal ureteral stones - Upper pole calyceal diverticulum - Complex lower pole stones - Horseshoe kidneys

Selection of Renal Access Site

Upper Pole Access Caveats

• Puncture during expiration

• Ensure working sheath remains in place for duration of procedure to avoid fluid accumulation in chest

• Post procedure chest flouro or x-ray

Imaging Modalities for Access in OR

• Fluoroscopic - Best delineation of calyceal anatomy - Use 18-gauge diamond-tipped needle

• Techniques:

- "Eye of Needle" - Triangulation

• AP plane:

• Visualize directly over both needle and calyx

• "bull's-eye" as visualize down shaft of needle

Imaging Modalities: “Eye of the Needle”

• Oblique plane:

• Allows evaluation of needle penetration depth

Imaging Modalities: “Eye of the Needle”

• Advantages: • Easier to keep access needle centered as

puncturing direct down onto calyx

• Disadvantages: • AP view includes surgeon's hand • Acute access angle may make wire

passage difficult, increases risk of torque injury

Imaging Modalities: “Eye of the Needle”

Imaging Modalities: Triangulation Technique

• C-arm angled away from pole of access Localize calyx of puncture in two planes

- Anterior-posterior (AP) to needle - Oblique to needle

Lower Pole Access Site

• AP plane (left - right adjustments):

Imaging Modalities: Triangulation Technique

• AP plane (left - right adjustments)

Too lateral Too medial Correct alignment

Imaging Modalities: Triangulation Technique

• Oblique plane (up - down adjustments)

Imaging Modalities: Triangulation Technique

• Oblique plane (up - down adjustments)

Correct alignment Too caudad Too cephalad

Imaging Modalities: Triangulation Technique

• Advantages - Keeps hands out of field - Calyceal access "end-on" - Access to any calyx from a single point

(i.e. subcostal upper pole) • Disadvantages

- More technically demanding to learn than "eye of needle" technique

- must center in two planes

Imaging Modalities: Triangulation Technique

• Place as much wire into the urinary tract as feasible - Ureteral placement is optimal - If unable to negotiate into ureter then

coil wire into peripheral portion of collecting system

Establishing Percutaneous Access

• Nearly frictionless • Kink-resistant • Initial wire for PNL

Hydrophilic, Nitinol Core Guidewire

Guide Wires

Securing Percutaneous Access

• Placement of safety wire - Once glidewire down ureter, feed

angiographic catheter over wire - Exchange glidewire with superstiff wire - Insert 8/10 coaxial catheter set - Secure safety wire (0.035" straight)

Percutaneous Access 3 Take Home Points

1. Thoughtful and accurate tract placement in most suitable calyx

2. Upper pole approach preferred - Staghorn, horseshoe

3. Know when to stop - Bleeding, infection

Tract Dilation

• Always monitor dilation process under fluoroscopy

• Methods: - Amplatz sequential dilators - Metal telescopic dilators - Balloon dilation catheter

Tract Dilation

• Inserted sequentially over 8F portion of coaxial set

• 30F sheath inserted over dilator

• Dilation process can be cumbersome

Amplatz sequential dilators (12 to 34F)

Tract Dilation

7F Balloon dilation catheter (Nephromax) • Inflate to 18 atm of pressure, 30F sheath placed

• Radial dilation in a single step

• Incomplete dilation if scar is present (seen by waist)

Tract Dilation: Caveats

Avoid dilation of infundibulum • Risks hemorrhage

Balloons may dilate beyond radiopaque marker

When in doubt • Err on side of

dilating short • ‘Scope to get the

“lay of the land”

Tract Dilatation: Balloon

CROES Tract Dilation Controversy • Original study indicated increased

hemorrhage with balloon dilation1

• Subsequent multivariate analysis2 • Balloon dilation NOT associated with

hemorrhage • Hemorrhage associated with

• Operative duration • Stone burden • Low volume institution • Larger sheath

1. Lopes T, et al. J Endourol 25:755-762; 2011 2. Yamaguchi A, et al. J Endourol 25:933-939; 2011

Variation in Tract Size: “Mini-”, “Ultra Mini-”, “Micro-”

Tract Size Benefits Cons Stone Removal

Mini1 13 Fr Limited blood loss & transfusion risk

Limited visualization, Longer OR time, technical limitations

Active

Ultra Mini2

11-12 Limited blood loss and transfusion risk

Longer OR time, technical limitations

Passage of fragments down ureter

Micro3,4 4.85 Fr all seeing needle

Limited blood loss Limit stone size and visualization, longer OR time

Passage of Fragments down ureter

1. Li L, et al. Urology 2010; 75:56-61 2. Desai J, et al. Biomed Res Int 2013; Epub 2013 Jul 24 3. Desai MR, et al. J Urol 2011; 186:140-5 4. Sabnis RB, et al. BJU Int 2013; 112:355-361

Other Types of Perc Access

• Ultrasound guided • CT guided

• complex anatomy • Laparoscopic guided

• Pelvic or ectopic kidney

• Retrograde endoscopic guidance

Ultrasound Guided Access

• 3.5/5 MHz probe with puncture attachment

• Advantages • Limits radiation exposure • Precise calyceal puncture • Avoid adjacent structure

• Disadvantage: steep learning curve

Desai M. J Endourol 23: 1641-1643, 2009

Removal of Stone • Ultrasonic lithotripsy

• Excellent suction • Not ideal for hard stones

• Pneumatic lithotripsy • Excellent stone breakage • Requires retrieval device

• Combination device • Suction limited

• Holmium laser lithotripsy • Requires retrieval device

Ultrasonic Lithotriptor Comparison

Efficiency ratios: Olympus LUS-2 1.0 ± 0.1 Circon-ACMI USL-2000 1.1 ± 0.3 Karl Storz Calcuson 1.4 ± 0.3 Olympus LUS-1 2.1 ± 0.5 Richard Wolf 2271.004 3.6 ± 0.8

LUS-2 = USL-2000 > Calcuson > LUS-1 > Wolf Mean penetration time differences were significant (p < 0.05)

Kuo RL et al. J Urol 170: 1101-1104, 2003

Outcomes of Combination Devices Compared to Ultrasound

Krambeck AE, et al. BJU Int 107:824-8, 2010

Flexible Nephroscopy

• Perform after stone removal

• Decrease need for additional treatments

• Limits access number

• Laser lithotripsy

• Baskets

• Amplatz sheath

• Pressurize irrigant to 300 mmHg

• Contrast plus fluoroscopy to assist in orientation, documentation

Flexible Nephroscopes: Set Up

Single vs. Multiple Access for Staghorn Calculi

• Single access • Upper pole, combo rigid & flexible with

holmium laser • Stone free rate 95%

• Advantages • 2.2% transfusion rate vs. 7.9-45% • Decrease renal damage/scarring?

• Disadvantage • Longer operative time

Williams SK et al. Cur Opin Urol 18: 224-8, 2008

Nephrostomy Tube • Smaller tube less discomfort1 • No influence on hemorrhage • More likely to occlude if

significant bleeding

• CROES large & small tube comparison2

• Large tubes less bleeding/ complications

1. Kim S et al. J Endourol 19:348-352; 2005 2. Cormio L et al. World J Urol Epub October 2012

8-10 Fr

Tubeless PCNL

• Replace NT with ureteral stent • Potential advantages

• Less pain • Quicker recovery

• Potential disadvantage • Loss of tract if 2nd PCNL necessary

Bellman GC, et al J Urol 157: 1578-82; 1997

Totally Tubeless PCNL

• No ureteral stent

• No nephrostomy tube

• Highly selected patients

Purpose of Nephrostomy Tube Post PCNL

• Aid in healing of tract • Promote hemostasis • Drain urine & prevent extravasation • Drain infection • Allow re-entry

Tubeless PCNL Conventional PCNL No intraoperative hemorrhage Intraoperative bleeding

No collecting system injury Perforation

Single or straightforward access Multiple or complex tracts

Subcostal access Supracostal access

Normal renal function CKD

Normalized coagulation profile Coagulopathy/bleeding diathesis

Normal platelet count Thrombocytopenia

Stone free status Residual calculi

Zilberman et al, J Urol 184:1261-6; 2010

Considering Tubeless PCNL

Conclusions

• Current era PCNL is in general a low morbidity procedure

• Consideration of anatomy, anomalies, and comorbidities should be made

• Multiple techniques and exit strategies exist and are considered safe

Thank you

Special Thank you to Dr. Lingeman for supplying video slide material