ABSTRACT
BACKGROUND: To avert nausea and vomiting the 5-Hydroxytryptamine3 (5-HT3) antagonists have become the first line of treatment ifassociated with cardiovascular effects andappear to cause QT prolongation. OBJECTIVE: Evaluate the effect of 1 mg, 4 mg, and 8 mg bolus doses of intravenous Ondansetron, relative to placebo, in prevention of postoperative nausea and vomiting (PONV) and to find out the changes of QT interval corrected for heart rate (QTc). MATERIALS AND METHODS: This prospective randomized, placebo-controlled, double-blind study was carried out among 136 adult participants of both sexes in a tertiary care postgraduate teaching institute at Kolkata. mg, 4 mg or 8 mg inj. Ondansetron was diluted to 10 ml with normal saline, was infused 30 min before extubation in relation with a control group. Time to first rescue antiemetic medication and in QTc interval at different time intervals, in each group was noted in different in the various surgical operation theaters (OTs). RESULTS: Requirement of the first rescue antiemetic in the postoperative period between 60 to 120 min in the mg, 4 mg or 8 mg Ondansetron groups was in 28%, 24% and 7% participants respectively; between 120 to 240 min in 63%, 72% and 57% respectively; and within 360 min in 9%, 4% and 36% respectively. Significant and maximal QTc prolongation was observed in the participants with mg or 8 mg Ondansetron 3 and 5 min of drug administration. CONCLUSIONS: One mg Ondansetron in healthy adult participants can effectively prevent PONV causing no or insignificant prolongation of QTc interval.
ABSTRACT
SUMMARY: Hypomagnesaemia is a common complication after cardiopulmonary bypass (CPB) and predisposes to the development of cardiac arrhythmias. Previous studies showed that intravenous magnesium reduces the incidence of postoperative cardiac arrhythmias but it also inhibits platelet function. Our aim was to compare the postoperative blood loss in patients not receiving magnesium after CPB with the group who received magnesium and to compare the requirement of blood, fresh frozen plasma (FFP) and platelets within 24 hours after surgery. This prospective randomized controlled study was conducted in 80 adult patients on oral aspirin undergoing elective CABG requiring CPB. Group A patients had not received magnesium infusion after recovery from CPB. Group B patients received magnesium infusion after recovery from CPB. Postoperative bleeding was assessed in both the groups. All the data were statistically analyzed. There was a insignificant increase in 24 hours postoperative drainage in magnesium recipient group compared to control group (p>0.05). Requirements of blood and blood products to maintain haematocrit and coagulation profile revealed insignificant (p > 0.05). Increase in requirement of PRC, FFP and platelets in magnesium recipient patients than the control group. Incidence of atrial fibrillation (Gr A 2.5%, Gr B 2.5%) and atrial extrasystoles (Gr A 2.5%, Gr B 10%) revealed comparable (p > 0.05) between the groups, but incidence of ventricular arrhythmias were significantly (p<0.05) high in the patients of Gr A(17.5%) than Gr B(5%). To conclude, magnesium may be administered to patients who continue pre-operative aspirin to undergo on-pump CABG surgery.
