Effects of fentanyl on pain and hemodynamic response after retrobulbar block in patients having phacoemulsification.

PURPOSE

To determine the effects of systemic fentanyl analgesia in preventing the pain related to the administration of retrobulbar anesthesia and cataract surgery.

SETTING

Departments of Ophthalmology and Anesthesiology, School of Medicine, Kocatepe University, Afyon, Turkey.

METHODS

One hundred twenty patients with American Society of Anesthesiologists physical status I to III scheduled for cataract surgery were evaluated in a single-blind randomized study. Patients with a history of hypertension, hyperthyroidism, or neurologic or psychiatric disorders were excluded. In the study (fentanyl) group, an intravenous bolus of fentanyl 2 microg/kg was slowly given 5 minutes before retrobulbar anesthesia was administered. In the control group, fentanyl was not given. There were 60 patients in each group. Demographic data were not statistically different between the 2 groups. The intensity of pain during injection and intraoperatively was measured by verbal pain scores. Hemodynamic stability was assessed by the heart rate (HR) and mean arterial pressure (MAP). End-tidal carbon dioxide concentrations and oxygen saturations were also recorded.

RESULTS

The changes in HR and MAP at 0, 10, 20, and 30 minutes were statistically significant between the fentanyl and control groups (P<.05). Fentanyl reduced pain scores significantly at all evaluations (P<.05).

CONCLUSION

The results suggest that fentanyl preemptively decreases injection and intraoperative hyperalgesia and provides hemodynamic stability without affecting patient cooperation, resulting in cataract surgery with retrobulbar anesthesia that is comfortable for both surgeon and patient.