OBJETIVE: An experimental study was done to evaluate the effect of nicotine on the healing of abdominal wall. METHODS: Sexteen Wistar rats weighing 210± 8g were randomly separated into two groups of eight rats each. In the group A Nicotine (Nicotinel Ò) was implanted in the back subcutaneous 5mg/Kg each two days, begining at the fifth preoperative day. A 5cm median laparotomy was done, sutured with nylon 5-0 and the rats were observed in individual cages. The group B (control) didn’t use nicotine. A multiperfurated silicone tube was implanted subcutaneously near the abdominal sutured lesion. In the tenth postoperative day 1ml of serous liquid was harvested from the silicone tube and a pO2 dosage was done. The rats were killed with overdose of anesthetic. A 2cm width transversal segment of abdominal wall was submited to tensile strength test by a tensiometer. A biopsy of the sutured area including muscle, aporeurosis and peritoneum was processed for histopatologic analysis by a digitalised system. The data were processed by the ANOVA and Newman-Keuls tests, considering significant the differences when p<0,05. RESULTS: In the group A the pO2 on the tissue serous liquid reached 17,75± 3,4 mmHg and in the group B (control) the pO2 = 40,75± 6,4 mmHg (p<0,01). The tensile strength reached 728,5± 161,75gf in the group A and 1241,6± 232gf in the control one (p<0,01).The mean density of the histopatologic elements was 105± 17,1 in group A and 146,2± 8,8 in group B (p<0,01). CONCLUSION: after evaluation of tissue pO2 , tensiometry and histopatology, the data permited to conclude that the nicotine has a deleterious effect on the healing the abdominal wall of rats.
Nicotine; Healing; Abdominal wall; Tensiometry; Histopatology; Oxigen
