Anastomoses

Definition: the surgical connection of separate or severed tubular hollow organs to form a continuous channel (e.g. bowel to bowel, ureter to bowel, artery to artery).

Techniques

1. Hand-sewn

2. Stapled.

Currently there is no evidence to suggest that either is superior to the other, providing attention is paid to factors that influence successful healing of anastomoses.

Types of anastomosis (Figure 152)

Hand-sewn bowel anastomoses use absorbable suture material (e.g. Vicryl, polydioxanone (PDS)) and aim to invert sutured edges. Sutures can be interrupted or continuous. Previously, the two-layer technique was employed, when a full thickness suture layer was created, followed by a second seromuscular layer (see Figure 155) that buried the first suture line. Now, a single-layered anastomosis is advocated. This incorporates an inversion of the sero-submucosal layer, again using an absorbable material (e.g. Vicryl).

Vascular anastomoses use non-absorbable suture material (e.g. Prolene). Suturing is continuous in order to provide an equal distribution of tensile strength throughout the anastomotic line. As opposed to bowel anastomoses, vascular suturing aims to evert the anastomotic edges.

Stapling devices

These are commercially available disposable devices. They consist of a ‘gun’ that has a stapling mechanism and a cutting mechanism.

CIRCULAR STAPLING (E.G. CEEA CIRCULAR ENDOSCOPIC ANASTOMOTIC STAPLER)

For end–end anastomoses. Two ends of bowel are physically apposed within the staple gun. When fired, the gun forms two circular rows of staples joining the two bowel ends. Two ‘doughnuts’ of excess tissue are then cut with the gun's knife.