PD56-06 TRANSFUSION RATES AFTER 800 AQUABLATION PROCEDURES USING VARIOUS HEMOSTASIS METHODS

Dean Elterman*, Thorsten Bach, Enrique Rijo, Vincent Misrai, Paul Anderson, Kevin C. Zorn, Naeem Bhojani, Albert El Hajj, Bilal Chughtai, and Mihir Desai

Objective

To determine if athermal methods are as effective in preventing blood transfusions as the use of

cautery across various prostate volumes following prostate tissue resection for benign prostatic

hyperplasia using Aquablation

Methods

The current commercial AQUABEAM robot that performs

Aquablation therapy was first used in 2014.

Since then, numerous clinical studies have been conducted in

various countries:§ Spain§ New Zealand§ United Kingdom§ United States

§ Australia§ Canada§ Germany§ India§ Lebanon

Determine the effectiveness of hemostatic techniques in reducing the transfusion rate

in patients after Aquablation

ALL CLINICAL TRIAL DATA SINCE 2014

EARLY COMMERCIAL PROCEDURES IN FRANCE, GERMANY & SPAIN

Definitions

HEMOSTASIS METHODS

Athermal: without the use of electrocautery

Bladder neck cautery: focal electrocautery around the bladder neck region

TRACTION

Robust: catheter tension of > 600 g (5.9N) with a catheter tension device (CTD)

Standard: taping the catheter to the leg, gauze knot synched up to the meatus or no traction at all

All patients received

continuous bladder irrigation

as per hospital standard practice

Baseline Characteristics

CHARACTERISTICNO TRANSFUSION

SUBGROUP(N = 770)

TRANSFUSION SUBGROUP

(N = 31)P

Prostate volume*, mL 66.3 (32.4, 20-280) 88.3 (34.4, 37-160) 0.001

Baseline hemoglobin*, g/dl 14.5 (1.4, 7.5-19) 13.6 (1.6, 8.7-16) 0.002

Resection time*, min 4.6 (2.7, 1-17) 6.7 (3.7, 2.4-17) 0.015

Bladder neck cautery, n (%) 141 (18) 8 (26) 0.343

Robust traction, n (%) 454 (59) 25 (81) 0.015

PSA*, ng/mL 4.9 (4.9, 0.1-36) 6.2 (3.7, 0.48-15) 0.082

*mean (SD, range)

Results: Chronological Transfusion Rates

PRE-WATER WATER* WATER II COMMERCIAL

Standard Robust Standard Robust Standard Robust Standard Robust

N 79 0 135 0 0 101 108 378

Prostate size, mL, median (range) 38 (28-133) 52 (25-80) 105 (80-150) 60 (20-160) 60 (20-280)

Transfusion rate, % 1.3 1.5 9.9 2.8 4.0

*includes roll-in and randomized patients

Results: Bladder neck cautery lowers transfusion rates in medium / large prostates - no impact on HGB

PROSTATE VOLUME TERTILE

PRO

PORT

ION

TRA

NSF

USE

D

0%

2%

4%

6%

8%

20-48

1.4%0.8%

48-77

2.5%

5.6%

77-280

1.7%

7.8%

PROSTATE VOLUME, mL

CHAN

GE

IN H

EMO

GLO

BIN

, g/d

l

-3

-2

-1

0

50 100 150 200

= standard traction without cautery= standard traction with cautery= robust traction

= standard traction with optional bladder neck cautery = robust traction

Hemostasis 5 Year Evolution: Optimal hemostasis method identified in 2019 after 800 patient analysis

Data on files as of 31Dec2019

N2014 – 2018

(n = 801)

0%

8%

6%

4%

2%

801

3.9%

322

CAU

TERY

1.9%

479

5.2%

7.8% in largest tertile (77-280 mL) prostates

No increase as prostates grow larger

CTD

(93%

ath

erm

al)

ALL

AVER

AGE

Hemostasis 5Y Evolution: Optimal hemostasis method identified in 2019 after 800 patient analysis

Data on files as of 31Dec2019

0%

8%

6%

4%

2%

N2014 – 2018

(n = 801)

801

3.9%

ALL

AVER

AGE

322

CAU

TERY

1.9%

479

5.2%CT

D (9

3% a

ther

mal

)

7.8% in largest tertile (77-280 mL) prostates

No increase as prostates grow larger

2019 (n = 952)

952

2.4%

ALL

AVER

AGE

266

PRO

PER

FLU

FFY

TISS

UE

(4 S

ITES

)

0.0%

670

3.4%

NO

FLU

FFY

TISS

UE

TRAI

NIN

G

16

PRO

SPTE

CTIV

E FL

UFF

Y TR

AIN

ING

(7 S

ITES

)

0.0%

O P T I M A L M E T H O D

I D E N T I F I E D

Transfusion results: Modified “Fluffy Tissue” protocol

NEW 3/188 (1.6%)0/16 (0.0%) 3/172 (1.7%)

EXPERIENCED

0/439 (0.0%)0/266 (0.0%) 0/173 (0.0%)

ALL 3/627 (0.5%)0/282 (0.0%) 3/345 (0.9%)

T O T A L(prostate size 20 – 230mL)2019 2020

New sites defined as 20 or less Aquablation casesExperienced sites defined as more than 20 Aquablation cases

Data as of 01Apr2020

Summary

• An evolution in understanding optimal hemostasis for Aquablation has led to the technique of clearing fluffy tissue at the bladder neck and applying focal cautery across various prostate volumes.

• This has resulted in a recent transfusion rate of 0.5% (3/627).