Evaluation of residual vascularisation in oesophageal substitution gastroplasty by surface oximetry-capnography and photoplethysmography. An experimental study.

OBJECTIVE

To evaluate residual vascularisation in gastroplasty and its possible relation to the development of anastomotic fistulas or dehiscences after oesophageal resection.

DESIGN

Experimental open study.

MATERIAL

Eleven mongrel dogs.

INTERVENTIONS

Gastric parietal blood flow was evaluated by photoplethysmography and measurement of surface oxygen and carbon dioxide tensions under basal conditions and after Akiyama's tubular gastroplasty. Temperature, heart rate, and electrocardiogram; arterial pressure, pulmonary arterial pressure, pulmonary capillary pressure, central venous pressure, cardiac output, venous oxygen saturation, and arterial blood gas tensions were monitored under stable haemodynamic conditions.

RESULTS

After gastroplasty, the mean serosal oxygen tension (pO2) of 8.6 mmHg and carbon dioxide tension (pCO2) of 99.5 mmHg and residual photoplethysmographic wave amplitude (8%) indicated considerable severe ischaemia at the fundus. There was relative ischaemia of the mid-stomach with residual mean values of 52.7 mmHg, 77.8 mmHg, and 57% for pO2; pCO2 and PPG wave amplitude, respectively.

CONCLUSIONS

Important devascularisation of the fundus, theoretically incompatible with healing, occurs after gastroplasty. Operative photoplethysmography and surface measurements of pO2 and pCO2 are good ways of evaluating the level and degree of ischaemia in gastric tubes for oesophageal replacement.