Effect of Khat (Qat) consumption on pain during and after local anesthesia for patients undergoing cataract surgery

The leaves of the Khat (Qat) plant (Catha edulis), which contain amphetamine-like compounds, are widely chewed in Yemen and East Africa for their pleasurable stimulant properties and for their psychostimulative effects. Khat consumption has a number of unwanted side-effects. This study investigates effects of Khat consumption on the quality of local anesthesia with peribulbar injection and patient perception of pain after administration of local anesthesia for routine cataract extraction.

This single-center, prospective trial included 323 consecutive patients undergoing routine cataract extraction for senile cataract. Cataract surgery was performed within 10 minutes of the administration of local anesthesia. The patients were divided into 2 groups: Group A for those who are consuming Khat on a regular basis and Group B for those who had not consumed Khat within the last 3 months. To assess pain experience during injection, intraoperatively, and postoperatively, each patient was asked to use a 10-point pain score chart.

The study included 164 males and 159 females. There were 121 patients (37.5%) in Group A and 202 patients (62.5%) in group B. All patients had peribulbar local anesthesia by 2-site injections. Group A had significantly greater pain scores during injection (p=0.000821) and intraoperatively (p=0.000001), but there was no difference in pain score postoperatively.

Khat consumption decreases pain threshold and affects patients' comfort during local anesthesia and during surgery in routine cataract surgery. Patients consuming Khat need more care during local anesthesia to make the surgery comfortable.