ISMJ

Background: In order to provide better hemodynamic control in patients with known ischemic  heart disase in phacoemulsification surgery under general anesthesia. In this study we compared Cutaneous Nitroglycerin and Intravenous Nitroglycerin on hemodynamic stability in this procedure under general anesthesia.

Material and Methods: In this randomized, prospective clinical trial study, 50 patients with 50- 70 years old candidate for phacoemulsification surgery under general anesthesiadivided two groups: 25 patients in control group received intravenous nitroglycerin and 25 ones in case group received cutaneous nitroglycerin. For the intravenous nitroglycerin patients group, before induction of anesthesia, 0.25–0.5 mcg/kg/min intravenous nitroglycerin started and the dose was adjusted according to the hemodynamic changes. All patients underwent cardiac monitoring for arrhythmia detection and S-T segment and T changes during anesthesia by NIBP and ECG monitoringwith a specified time (before induction of anesthesia 1 and 3 minutes after induction after the placement of laryngeal mask after the incision of surgery and after removal of the mask) were recorded.A nitroglycerin skin patch (ointment 2%) of up to 2 cm was applied  in the anterior chest wall 40 minutes before the induction of anesthesia.All patients operated with same method in phacoemulsification surgery without epinephrine solution.A statistical analysis was performed with SPSS software (version 16).A p-value less than 0.05 was considered statistically significant.

Results: There were no difference between groups in Mean age and sex, baseline hemodynamic values including: systolic blood pressure, diastolic blood pressure, heart rate, and mean arterial pressure.The systolic blood pressure in the intravenous nitroglycerin group in the third minute after induction of anesthesia, insertion of laryngeal mask, and removal of the mask and one hour after surgery was lower than that of the nitroglycerin skin group this difference was statistically significant.Diastolic blood pressure in the intravenous nitroglycerin group was lower than other groups after removal of the laryngeal mask than that of the nitroglycerin skin group this difference was statistically significant.Heart rates in the intravenous nitroglycerin group at the third minute after induction of anesthesia, insertion of the laryngeal mask, and stimulation surgery were higher than in those of the nitroglycerin skin groups this difference was statistically significant.No statistical significances were discovered in mean arterial blood pressure in both groups. A statistical analysis was performed with SPSS software (version 16).A p-value less than 0.05 was considered statistically significant.

Conclusion: In this study our findings demonstrate that the nitroglycerin skin patch in patients with known ischemic heart disease undergoing phacoemulsification surgery under general anesthesia induces hemodynamic stability. Intraoperative events such as systolic hypertension, diastolic hypotension, and persistent tachycardia  does not  affect  known ischemic patients with cutaneous nitroglycerin.