Material and Method: The present prospective study included Thai adults who underwent elective open laparotomy at the Department of Surgery, Faculty of Medicine Siriraj Hospital between August 2011 and May 2012. Patients who had previous laparotomy, intra-abdominal adhesions, or gross abnormality of SB were excluded. The length of SB was measured using an umbilical cord tape, from the duodeno-jejunal junction to the ileo-cecal valve.

Results: Sixty-four patients were enrolled during the study period. According to the exclusion criteria, only 48 patients were eligible for study. There were 27 men and 21 women, with an average age of 60 years (range 28-88). The average length of SB (only jejunum and ileum) was 428±105 cm (range 169-745). Male adults had about 90 cm longer SB than female adults (468±105 cm vs. 376±81 cm; p<0.01), particularly of the jejunum (179±78 cm vs. 106±38 cm; p<0.01). The ileum accounted for about two-third of the total SB length. There was no association between SB length and age, body weight, height, or body mass index.

Conclusion: Based on the present study, the total length of small bowel (jejunum and ileum) in Thai patients was approximately 430 cm. Male adults had significant longer SB than female adults, particularly the jejunal segment.

Keywords: Small bowel, Jejunum, Ileum, Anatomy, Length, Thailand