Background Multidisciplinary treatment of short bowel syndrome (SBS) has been a success story for paediatric surgery. Longitudinal intestinal lengthening and tailoring (LILT) is the archetypal autologous gastrointestinal reconstruction procedure, but despite it being performed routinely in intestinal rehabilitation departments, the physiological basis behind it is poorly understood. We attempt to analyse the features that improve intestinal adaptation and offer a LILT theoretical model.
Methods Based on our clinical experience on 59 LILT procedures over 30 years, we set up a concise theoretical model that describes post-LILT bowel adaptation in a holistic way.
Results Intestinal adaptation is affected by many factors, including remaining bowel length, the presence of the ileocaecal valve and colon, underlying disease process, nutritional status, hepatobiliary function, and bacterial flora. Lengthening techniques do not affect the absorptive surface, although changes in the microvilli have been observed in animal models. Dilated dysmotile intestinal segments benefit from tapering because reduction in the intestinal lumen calibre allows better peristalsis, as demonstrated by improvements in intestinal transit time. Tapering also helps prevention of stasis and subsequently reduction of bacterial overgrowth. Additionally, reduction in bowel diameter decreases the volume to surface ratio, theoretically allowing for more effective contact of the chime with the absorptive surface.
Conclusions LILT has become an essential component in the management of SBS. The physiological principles described above provide a theoretical basis that explains the absorptive advantage offered by the LILT. Further research is necessary to quantify the effect of these procedures on the microscopic and hormonal levels.