RESUMO
Dexamethasone in a dose of 1mg/kg has been proved to be effective in prevention of PONV. Smaller dose [0.5mg/kg] of dexamethasone was applied in the present study. One twenty children, 5-15 years old, scheduled for strabismus surgery, were randomly allocated to 3 groups. Patients in groups A and B received dexamethasone 1mg/kg and 0.5 mg/kg respectively, immediately after induction while group C received saline. Induction with sevoflurane, fentanyl and cistracurium followed by LMA insertion and mechanical ventilation. Incidence and severity of PONV, ondansetrone requirements, duration of stay in PACU and parental satisfaction were recorded for every patient. Statistical analysis was done using Kruskal-Wallis followed by Mann-Whitney U test for non-parametric data and ANOVA for parametric data. There was no significant difference between groups as regard the risk factors for PONV. Incidence of PONV during early [0-6h] postoperative periods was significantly lower in both dexamethasone groups A and B compared with control group C [12.5% and 15% Vs 30% with P value c 0.01]. Incidence of PONV during late postoperative period [6-24 h] was also significantly less in groups A and B compared so group C [7.5% and 12.5% Vs 223% with P value of 0.01 and 0.03 respectively]. Severe PONV [score=3] was found in 23% of patients in groups A and B compared to 7.5% in group C during early post operative period [P value = 0.04] Nausea alone [score=l] was also less in group A and B compared with C [5% and 73% Vs 12.5% with P value of 0.01 and 0.04 respectively] in early postoperative period. Rescue antiemetic drug [ondansetrone] was given to 323% of patients in control group [group C] compared with 123% and 173% in groups A and B with P value of 0.01 and 0.02 respectively. Duration of stay in PACU was significantly shorter in group A and B [128.3[35.7 and 130.6[41.9 min] compared with control group [147.5[33.2min] with P value of 0.02 and 0.03 respectively. Parental satisfaction was also less in control group. We concluded that dexamethasone could decrease PONV and ondansetrone requirements. Smaller dose of dexamethasone [0.5 mg/Kg was as effective as that dose already used by others [1 mg/Kg] especially during early postoperative period