Proposal of a novel method to evaluate anastomotic tension in esophageal atresia with a distal tracheoesophageal fistula

Anastomotic tension with the potential to lead to post-operative complication is usually evaluated using gap length before anastomosis in patients with esophageal atresia and a distal tracheoesophageal fistula (EA with a TEF). However a uniform, accurate measurement of gap length is not possible and estimation of the length the delicate distal esophageal stump is stretched by the anastomosis may have greater utility. The aim of this paper was to propose a novel method to evaluate the anastomotic tension in EA with a TEF. Forty consecutive patients having EA with a TEF were studied. Primary anastomosis without gastrostomy was performed in all cases. When the TEF was cut off, the most proximal site of the tracheal side was marked using a tiny metallic clip. When anastomosis was completed, the distance from the clip to the anastomotic site was measured as the stretched length. On the esophagram taken subsequently, the same distance was measured, together with the distance from the clip to the esophago-cardiac junction as the original distal esophageal length. The stretching ratio was calculated by dividing the former by the latter. The stretched length on esophagram (median: 3.0 mm, range: −12 to 21) was significantly correlated with that measured during surgery (median: 2.3 mm, range; −14 to 15) (r=0.96, P<0.0001). The median of original distal esophageal lengths was 60.0 mm (range: 35–80). The stretching ratio was significantly correlated with the stretched length, and the number of the stretching ratio as a percentage corresponded to about double the number of the stretched length on esophagram in millimeters (y=1.91x+0.58, r=0.98, P<0.0001). Anastomotic leakage and recurrence of TEF were not experienced. In patients complicated with gastroesophageal reflux (GER), the site of TEF was significantly more distal as compared with the other cases [median (range): 5.0th (4.0–6.0) vs 3.5th (1.5–5.0) thoracic vertebral level, P<0.009]. The stretched length and the stretching ratio were also longer and larger, respectively [median (range): 10.0 mm (6–21) vs 2.0 (−12 to 14) mm, P<0.008, 17.3% (12.7–47.7) vs 2.9% (−16.4 to 29.8)%, P<0.018). Similar tendencies were observed for patients complicated with stricture. Estimation of the stretched length of the distal esophageal stump is useful to evaluate the anastomotic tension. If the stretched length is more than 10 mm, it will be necessary to consider the possibility that stricture or GER may arise afterwards.