Tesi di specializzazione (5 anni)
Adhesive Small Bowel Occlusion: which CT signs predict surgery?
RICERCA TRASLAZIONALE E DELLE NUOVE TECNOLOGIE IN MEDICINA E CHIRURGIA
Corso di studi
relatore Prof. Caramella, Davide
correlatore Dott. Tonerini, Michele
correlatore Dott. Tonerini, Michele
- Surgery due to ischemia
- Gastrografin® test
- Non Operative Management
- Emergency surgical treatment.
- Adhesive Small Bowel Occlusion
Data inizio appello
- Objectives: To determine in adhesive small bowel occlusion (ASBO), which MDCT findings are predictive for the failure of a non-operative management (NOM), of Gastrografin® test outcome and finally for the need of surgery.<br><br>- Methods and Materials: From January 2015 to April 2017 we examined 137 admissions for ASBO: 71 Females, 66 Males, mean age 69 years (10-97), at our first level Emergency Department (ED). We excluded the patients without an adherential occlusion and those patients with spontaneous resolution of the bowel occlusion before the Gastrografin® test. This test is based on administration of the water soluble contrast (per os or via NGT) and to follow the progression of the contrast by means of seriated abdominal X-rays. It is considered successful if the cecum is opacified within eight hours.<br>The MDCT parameters, taken in consideration, were twelve: maximum caliber of the bowel; wall thickness greater than 5mm; parietal pneumatosis; presence or absence of peritoneal free abdominal fluid (FAF), peritoneal fluid density (measured in Hounsfield Units-H.U.); whirl sign; number of transition points; closed loop obstruction; small bowel feces sign; reduced bowel wall enhancement (RBE); mesenteric fluid congestion and fat notch sign.<br>The peritoneal fluid density has been considered measurable in the 84 admissions in which FAF, identified on MDCT, resulted to be sized >3cm2. The HU was measured by a round region of interest (ROI) positioned in the largest and lower pool of FAF (to include eventual blood stratifications) avoiding adjacent structures. A sensitivity analysis was performed to determine a high-density HU threshold. The FAF density in patients who underwent therapeutic laparotomy due to ischemia was compared with those successfully discharged without surgical approach. <br>We evaluated the previously mentioned MDCT parameters: a) in all the patients that underwent surgery (n=86), b) in the group of patients treated surgically owing to ischemia (n=22), c) in the patients treated successfully with NOM implemented by Gastrografin® test (n=51) and d) in patients that underwent failed NOM implemented by Gastrografin® test (n=56) to find out any MDCT sign predictive of NOM failure.<br><br>- Results: The RBE resulted to be the more significant MDCT parameter (p value: <0,025) in predicting the surgical approach in general. Wall thickness greater than 5mm (p value: <0,0001); presence of peritoneal fluid (p value: 0,013); closed loop obstruction (p value: 0,044); RBE (p value: <0,0001) resulted to be significant in the prediction of surgery due to ischemia. Peritoneal fluid density (measured in HU) resulted to be significant for ischemia too and a best cut off value of 13,5-14,5 HU has been found with an AUC of 0,69 and a p value of 0,012. In fact, all patients with FAF density >14,5 UH resulted to need surgery due to ischemia with a sensitivity of 79% and specificity of 55%, PPV of 34% and NPV 90% an accuracy of 60% and a Youden Index of 0,34. The other MDCT parameters did not show any significant correlation.<br>In our study no MDCT sign resulted to be significant in prediction of a failure of NOM performed with Gastrografin® test. <br><br>- Conclusions: In ASBO, MDCT is fundamental for the management of the patients. Among the MDCT findings, RBE resulted significant in predicting the need of a surgical approach in general; while thickness greater than 5mm, presence of peritoneal fluid, closed loop obstruction, RBE and an increased peritoneal fluid density ( >14,5 UH) are useful to elaborate a model to predict surgery due to ischemic complications. No MDCT parameter resulted to be significant in prediction of a failure of NOM implemented with Gastrografin® test.<br>