1. BACKGROUND TO GI ANASTOMOSIS

The techniques of joining two pieces of bowel together are central to gastro-intestinal surgery and, as such, are skills that all general surgical trainees have to master. This may involve a simple end-end anastomosis of two pieces of jejunum, a more complex colo-anal anastomosis or alternatively a biliary enteric join. In all cases, the consequences of a failed anastomosis are severe and frequently life-threatening (Table 1).

Why do gastro-intestinal anastomoses fail?

There are many reasons, but very broadly these may be divided into the following categories:

• Poor selection, ie the clinical situation was not such that an anastomosis was the correct decision
• Poor preparation of the intestine for the anastomosis, ie the bowel ends were under tension, were of poor vascularity or there was a distal obstruction
• Poor technique, ie sutures were not inserted correctly, knots were tied too tightly and the ends rendered ischaemic or a staple gun was not used correctly
• Poor post-operative care such that the patient became hypoxic or hypotensive leading to tissue ischaemia and delayed healing

The first three reasons are probably the most common causes of anastomotic failure, but in all cases the occurrence of an anastomotic leak is a reflection on the operative skills of the surgeon, their decision-making and the skill of the surgical team. Anastomotic failure is an aspect of surgical practice that is directly dependent upon the skill and care of the operator - something that is frequently emphasised in peri-operative mortality audits.(1) It is also a complication that can potentially be reduced by better training. As such, it is essential that trainees be taught a safe, reliable and repeatable technique that works.

Once the basics have been mastered it is important to continue to pay the same meticulous attention to each anastomosis you perform and to monitor your results and outcomes. If you are to improve your skills you must be honest with yourself as to why any problems arose and, thereafter, take steps to correct these. Remember that even the best surgeons have problem cases, make decisions which in retrospect were wrong and have technical problems - but to improve you must learn from these. This is a continuous process throughout a surgical lifetime.

There are many techniques for gastro-intestinal anastomosis, including both mechanical stapled techniques and hand-sutured procedures. Good results are achievable with each technique provided that care is taken in the preparation of the bowel and if performed well in expert hands. For the purpose of this course we are going to demonstrate a single-layered, sero-submucosal sutured anastomosis. The basic technique will be demonstrated for an end-end small bowel anastomosis and thereafter you will be shown modifications which allow this technique to be applied to different situations that you may encounter.

The rationale for a sero-submucosal technique is that the sutures include the strong, submucosal tissue (composed largely of collagen) while not incorporating the mucosa with the risk of inducing ischaemia. The result will be an inverted anastomosis (Figure 1.1). The performance of this technique and its modifications have been shown to be safe in different anatomical sites.(2-8) Furthermore, the use of a single-layered technique has been shown to be superior to a two-layered anastomosis in terms of time to perform, outcome and ease of teaching.(9,10)

Figure 1.1 A single layer sero-submucosal anastomosis

In addition to the sutured anastomosis, you will be introduced to some basic stapling techniques.

It will not be possible in a single day to make each of the participants an expert in all aspects of anastomotic technique. It is, however, hoped to introduce you to the techniques involved and instill the realisation of the importance of gastro-intestinal anastomosis which should be further developed in your day-to-day surgical practice.

METHODS

This course will involve lectures and practical sessions in which you will be expected to perform a series of anastomoses. The emphasis will be on the practicalities and techniques. These chapters will provide additional materials and descriptions of how the demonstrations apply in clinical situations and more detailed, theoretical background.

As mentioned previously, this course is only a beginning and to be truly successful it should stimulate you to constantly improve your own technique. There are many ways in which this can be achieved but this will certainly involve observation of experienced surgeons, supervised operating and constant self-appraisal. We will be using self audit and peer review during the course as you will be asked to assess your own and your partner's performance throughout the day using a structured assessment form (Appendix 1). This form can be readily applied to your own clinical practice and will be of value in continued self-appraisal.