Objective Measurement of Adequacy of Vascular Anastomosis in Renal Transplant

Dr Ajay Aspari RaghunathDr Dilip C DhanpalDepartment of Nephro-Urology and Transplantation

Sagar Hospitals, Jayanagar

Bangalore

IntroductionProblems with Inadequate Vascular

Anastomosis

◦Thrombotic complications Renal Artery Thrombosis

◦Stenotic Complications Renal Artery Stenosis

◦Haemorrhagic Complications

AFFECTING GRAFT AND PATIENT SURVIVALOsmany , Shokeir A , Ali-el Dein B et al [2003]Vascular Complications After Live Donor Renal

Transplantation: Study of Risk Factors And Effects on Graft and Patient survival. Journal of Urology 169, 859–862

Introduction contd.

Criteria for assessment of Adequacy of Vascular Anastomosis in Renal transplant

Subjective Criteria◦ Thrill◦ Pulsations

Surrogate Criteria◦ Colour of Kidney◦ Turgidity of Kidney◦ Immediate urine output via transplanted kidney

NO OBJECTIVE CRITERION FOR A GOOD ANASTOMOSIS INTRAOPERATIVELY

1 2

3 4

If the above are NOT satisfied,◦ Systemic Measures

Central Venous Pressure Blood Pressure

◦ Local Measures Intra arterial Papaverine Periarterial Lignocaine spray On table USG Doppler Biopsy of Kidney [ in case of suspected rejection ]

A redo anastomosis is in order if the above are not satisfactory

. John M Barry, Transplantation as Treatment of End-Stage Renal Disease and Technical Aspects of Renal transplantation

AimTo define an objective

measurement of Vascular Anastomotic adequacy

Pilot study

First ever Objective Criteria to be described

Materials and MethodsRecruitment

◦ Every consecutive patient undergoing transplant◦ End to End anastomosis [Internal Iliac A. to Tx Renal

A. ]

Exclusion◦ Pediatric◦ End to side [External Iliac A. To Tx Renal A.]◦ Thromboendarterectomy [ 1 case ]

22G Cannula for intra arterial pressure◦ Why 22 Gauge ??◦ Measurement across anastomosis

Technique

Study period – January 2011 to Date

SITE OF ANASTOMOSIS

PRE ANASTOMOTIC PRESSURE

Follow upUSG Doppler studies

◦Post Operative Day -1Evaluation of Renal Blood flow

◦From Renal artery upto Arcuate arteries

Resistive Index Criteria Main Renal Artery

Divisional Artery◦ Anterior◦ Posterior

Segmental Artery

Interlobar Artery

Lobular Artery

Arcuate Artery

Resistive Index CriteriaTool for assessing changes in

renal perfusion

Line H , Naesens M , Lerut E et al [2013] Intrarenal Resistive Index after Renal Transplantation. New England Journal of Medicine.  369:1797-1806

M Darnel, D Schnell, F Zeni [2010] Doppler-Based Renal Resistive Index: A Comprehensive Review. Yearbook of Intensive Care and Emergency Medicine. pp 331-338

Resistive Index Criteria

Accepted RI Criteria –◦0.6 – 0.8

Line H , Naesens M , Lerut E et al [2013] Intrarenal Resistive Index after Renal Transplantation. New England Journal of Medicine.  369:1797-1806

Resistive Index

Pulsatility index◦ [ Systolic Velocity – Diastolic Velocity] /

Mean Velocity

Results13 casesLeast gradient = 6 mm HgHighest Gradient = 17 mm Hg

◦Mean Pressure gradient = 10.76 mmHg

◦Median Pressure Gradient = 9 mm Hg

◦Mode = 12 mm Hg

Pressure Gradient

Resistive Index -Hilar

Resistive Index- Segmental Arteries

Resistive Index –Arcuate Arteries

1 12 0.76 0.70 0.69

2 14 0.78 0.73 0.7

3 9 0.67 0.51 0.54

4 11 0.64 0.53 0.52

5 14 0.73 0.7 0.67

6 12 0.7 0.67 0.65

7 8 0.6 0.51 0.51

8 7 0.59 0.54 0.52

9 6 0.54 0.58 0.55

10 8 0.57 0.61 0.58

11 10 0.74 0.68 0.61

12 12 0.71 0.66 0.57

13 17 0.79 0.77 0.74

Correlation Coefficients◦Pressure gradient vs Resistive index

Hilarr = 0.9

Segmental Arteriesr = 0.81

ArcuateArteriesr = 0.85

DiscussionCorrelation between Pressure

gradient and Vascular resistive index

◦Higher the gradient, higher the resistance

Utility of pressure gradient

DiscussionWhy not Doppler On Table??

◦Doppler may pick up readings only for stenosis beyond 60-70%

◦Not reflective of mild to moderate stenosis

Doppler studies are no longer done to diagnose Renal Artery Stenosis

DiscussionSuch a technique has been recommended

for Lung transplant

Has been carried out in Coronary artery surgeries◦ > 30mm Hg is unacceptable warranting a

redo anastomosisNo literature for Renal transplant

◦ Since Renal Vessels are bigger than Coronary vessels, we arbitrarily propose a cut off of 20 mmHg

Siddiqui A ,Bose A K, Ozalp F et al [2013] Vascular anastomotic complications in lung transplantation: a single institution’s experience. Interactive CardioVascular and Thoracic Surgery 17 - 625–631

DiscussionTo define the Criterion based on

Pressure Gradient

◦Require further studies and also animal experiments

ConclusionSimple method for measurement of

Vascular Adequacy

Application of Pressure gradient measurement will reflect:

◦Lesser rates of failed transplant

◦Criterion useful for Young Transplant surgeons Eg. at high volume centres and teaching institutes

where in inadequate anastomosis on table is quickly detected and a redo is done rather than flogging a tired horse

References Osmany , Shokeir A , Ali-el Dein B et al [2003]Vascular

Complications After Live Donor Renal Transplantation: Study of Risk Factors And Effects on Graft and Patient survival. Journal of Urology 169, 859–862

John M Barry, Transplantation as Treatment of End-Stage Renal Disease and Technical Aspects of Renal Transplantation

Line H , Naesens M , Lerut E et al [2013] Intrarenal Resistive Index after Renal Transplantation. New England Journal of Medicine.  369:1797-1806

M Darnel, D Schnell, F Zeni [2010] Doppler-Based Renal Resistive Index: A Comprehensive Review. Yearbook of Intensive Care and Emergency Medicine. pp 331-338

Siddiqui A ,Bose A K, Ozalp F et al [2013] Vascular anastomotic complications in lung transplantation: a single institution’s experience. Interactive CardioVascular and Thoracic Surgery 17 - 625–631

Thank You