“Challenges In Peribulbar Anaesthesia Among Mishri Users Undergoing Cataract Surgery”

Mishri, a roasted tobacco powder used as a dentifrice, is widely consumed in central and southern regions of India. Its prevalence ranges from 17% to 45% in certain populations. The principal active component, nicotine, produces sympathetic stimulation and vascular effects that may alter the pharmacodynamics of the local anesthetic agent and, in turn, the efficacy of the same.Peribulbar anesthesia is a common regional block used in cataract surgery to provide both analgesia and akinesia. It remains the standard in teaching hospitals; however, many private practitioners prefer performing cataract surgeries under topical or sub-tenon’s anesthesia.

Prospective comparative study conducted at a tertiary care ophthalmology center in Nashik, India

This is a prospective interventional study. A total of 60 patients undergoing elective cataract surgery were included. Out of 60 patients, 30 were Mishri users and 30 were non-Mishri users. Exclusion criteria used—active smoking habits or chewing tobacco, those who were on anticoagulants or had high cardiac risks or high myopia were excluded from the study.A peribulbar block of 5 ml was given by using plain xylocaine 2% mixed with hyaluronidase. After 5 minutes and 10 minutes, muscle movements and pain sensation were checked. The akinesia score (0-8) was assessed at the end of 5 and 10 minutes. An additional block was given if the patient experienced pain or akinesia was not achieved. Post-operative pain was measured using VAS at 1 hour. 

The average amount of Anaesthetic drug required in Mishri users is 8 ml and in non-Mishri users, it is 5.2 ml.At 5 minutes, akinesia scores were significantly lower in Mishri users (4.8 +/- 1.3) compared to non-users (6.1 +/- 1.0). At 10 minutes, scores were 6.5 +/- 0.9 versus 7.2 +/- 0.8, respectively (p < 0.005). Post-operative VAS at 1 hour was higher in Mishri users (36% vs 12%; p < 0.005).

Chronic mishri use significantly delays the onset of akinesia and shortens sensory block duration. There is an early onset of postoperative pain. Preoperative identification of smokeless tobacco use is essential to optimize anesthetic management.