Objective      To explore the effect of different output parameters of argon plasma coagulation (APC) equipment on esophageal injury in dogs

and to investigate the safe range of APC treatment for esophageal diseases.       Methods      (1) Esophageal mucosa of three dogs was solidified with APC using different output power (50

60

70 and 80 W)

argon flow (1.6

2.0 and 2.4 L/min) and acting time (2 and 4 s). After slicing and HE staining

the depth of tissue damage was observed with an optical microscope. (2) Esophageal mucosa of two dogs was solidified with APC using argon flow of 2.0 L/min

acting time of 3 s and different output power (50

60

70

80

90 and 100 W). After slicing and HE staining

the depth of tissue damage was observed with an optical microscope. (3) Eight dogs were randomly divided into two groups. The esophageal mucosa at forty centimeters away from the incisor was annularly burned with APC using output power of 60 and 70 W. The mucosal scar formation and esophageal stenosis was observed by gastroscopy and ultrasound gastroscopy after 2 and 4 weeks.       Results      The depth of esophageal tissue damage was positively correlated with the APC output power

argon flow and acting time. The output power had the greatest effect on the depth of damage. In condition of fixed argon flow and acting time

pathological score of esophageal tissue damage increased with the rise of power. Within the range of 70 to 90 W

the variation of tissue injury was not significant. After 2 and 4 weeks

the scar formation and esophageal stenosis in esophageal injury site was observed with the APC output parameter of 70 W (2 L

3 s). However

the scar formation and esophageal stenosis was not obvious with the APC output parameter of 60 W (2 L

3 s).       Conclusion      By selecting the appropriate APC output parameters

we could control the degree of esophageal injury. The output power of 60 W or less can effectively prevent the occurrence of complications such as APC postoperative esophageal stenosis.