CONGRESSO FUNDACIONAL DE LA

SOCIEDAD ESPAŇOLA DEL ACCESO VASCULAR

SEDAV Madrid 7-8 Noviembre 2014

MICROCIRURGIA y HEMOSTASIA PREVENTIVA

Nicola Pirozzi

Roma

nicola.pirozzi@uniroma1.it

www.nefrologiainterventistica.com

Mortality (vs AVF):

CVC: RR 1.32;

95% CI, 1.22 to 1.42; P < 0.001

Graft: RR 1.15;

95% CI, 1.06 to 1.25; P < 0.001

Rodriguez, J. A. et al. Nephrol. Dial. Transplant. 2000 15:402-408;

Actuarial curve of primary patency of different modalities of A-V fistulae

Modified from L.Turmel Rodrigues, Marseille 2012, http://www.sfav.org/Publication/SFAV2012/002.pdfModified from L.Turmel Rodrigues, Marseille 2012, http://www.sfav.org/Publication/SFAV2012/002.pdf

AUTOLOGOUS ARTERIO-VENOUS FISTULA (AVF)

78.5% OF PREVALENT PTS IN ITALY

Distal AVF 88%

Proximal AVF 12%

Elderly, diabetic and dialysis vintage >10y included

DISTAL ACCESS

Early failure

Delayed maturation

- Inflow (proximal artery stenosis)

- Outflow (mid/distal vein stenosis)

Pre-operative evaluation

Post-operative intervention

- Early thrombosis*

- Anastomosis stenosis

- Juxta-anastomotic vein stenosis

* possible also: clotting defects, hypotension Turmel-Rodrigues, L. et al. Nephrol. Dial. Transplant. 2001

Surgery Technical refinements

DISTAL ACCESS SURGERY

Microsurgery:

Magnification of images (loop glasses, operating microscope)

Dedicated instruments (pince, forcep, needelholder, clamp)

Sutures: poliamide – polipropilene (8-0, 9-0..12-0)

Preventive haemostasis

Pneumatic tourniquet

- Operative field visualisation

- Sharpness of procedures

- Reduced vascular traumatism

MICROSURGERY

• Extreme precision even on small

and difficult vessel

• Favour the respect of the structure

anatomy

Loop (2x 3x..)

Operative Microscope ( >15x )

MicroSurgery

- Intima respect

- Sharp artery /vein wall apposition

- Avoiding adventitial “infiltration”

- Valvulectomy

- Avoiding twisting, kinking, narrowing …

• Operative field visualization

• Reduced traumatism of the vascular wall

- Vascular clamp unnecessary

- No dissection of radial artery

• Loco-regional anaesthesia (plexus block)

PREVENTIVE HAEMOSTASIS

BRACHIAL PLEXIC BLOCK

Hemodynamic effects

VPS (cm/sec)

VTD (cm/sec)

IR IR

Pre Post Pre Post Pre Post*

43,53 48,84 -5,23 13,59 1,16 0,71

Pirozzi et al GIN 2010 (27) S51 Pirozzi et al JVA 2012

* 360min

Long lasting vasodilatation (6h)

evidence based medicine

Arteriovenous angioaccesses in children:

major publications since 1990

Bourquelot

(E.U.)

Sanabia

(E.U.)

Lumsden

(USA)

Bagolan

(E.U.)

Sheth

(USA)

Year 1990 1993 1994 1998 2002

Microsurgery + + – + –

Number of

accesses

434 86 61 112 52

Failed to

mature AVF

10% 10% 30% 5% 33%

% Grafts 7% 14% 76% 0% 54%

AVF, Arteriovenous fistulas.

Bourquelot et al Ther.Aph.Dial 2003

MICROSURGERY

Adults: still an open debate

“…there are two different “schools of thinking”.

http://www.vascularaccesssociety.com

Guidelines: Create forearm A/V_fistula

RCT lack

EBPG KDOQI guide-lines: no mention about technique

Emerging evidence:..

Immediate thrombosis (24h after surgery): 0%

Early failure: 14.28% (4/28pts)

- Thrombosis 1pts (14° after surgery)

- Lack of maturation (patent VA):

juxta-anastomotic vein stenosis (2pts)

mid-vein stenosis (1pts)

95.8%

Pirozzi et al NDT 2010

RC-AVF A.RAD < 1.6mm

Radial artery

1.36 mm 0,16

(1-1.6mm)

Cephalic vein

1,91 mm 0,32

(1.2-2.5mm)

Bourquelot et al JVS 2011

UB-AVF

70 pts (63 adult, 7 children)

Immediate success

94% (adults)

100% (children)

- In use access 60% after 80 days

- 1y PP 42%

- 1y SP 60%

65 pts >70y: 70.8% RCAVF

Early failure: 13%

1y primary patency 63%

1y secondary patency 80%

No significant difference (EF, PP,SP) vs <70y pts

MICROSURGERY IN THE

ELDERLY

Pirozzi et al JVA 2014

MICROSURGERY = PATENT DISTAL ANASTOMOSIS

then

Multidisciplinary approach => help functional/patency

- OBESITY:

Lipectomy Bourquelot et al JVS 2009

- FOREARM ARTERY STENOSIS:

PTA Turmel Rodrigues NDT 2009 Raynaud et al JVS 2009

- IUXTA-ANASTOMOTIC VEIN STENOSIS:

Proximalisation / PTA Tessitore Clin J Am Soc Nephrol 2006, Long B et al JVS 2010

- MID-VEIN / OUTFLOW VEIN STENOSIS:

PTA +/- stenting Turmel Rodrigues et al NDT 2001, Nat Clin Pract Neph 2008

Multidisciplinary approach => help functional/patency

CONCLUSIONS

-The main challenge of distal anastomosis is the deal with small, thin,

fragile vessels.

Calcifications: sometimes impossible to create any anastomosis

- No definitive validation of any surgical procedure

- Microsurgery (and preventive haemostasis) seem to match

the needs of a correct surgical procedure able to lead to a patent

anastomosis

- Consistent results on children, emerging evidence on adults

CONCLUSIONS

- Cardiovascular and plastic reconstructive surgery moved to

microsurgical techniques long time ago (facing the same vessels)

- It is time to such a change in practice even for vascular access surgery?

- More evidence would be provided, stronger conclusion could be drawn

Muchas gracias

et SUERTE a la SEDAV!!

Nicola Pirozzi

nicola.pirozzi@uniroma1.it www.nefrologiainterventistica.com

Pirozzi et al GIN 2010 (27) S51

VIDEO 1

PREVENTIVE HAEMOSTASIS

CREATION: UB-AVF

Pirozzi et al GIN 2010 (27) S51

VIDEO 2

MICROSURGERY (Courtesy of Dr. Pierre Bourquelot)

Pirozzi et al GIN 2010 (27) S51

VIDEO 3

PREVENTIVE HAEMOSTASIS:

SUPERFICIALISATION BY LIPECTOMY