An Observational Study of Adductor Canal Block Using Ropivacaine Alone and with Additives (Dexmedetomidine / Fentanyl) for Post Operative Analgesia in Patients Undergoing Knee Arthroscopic Surgeries

Abstract

Background:Knee arthroscopy surgery is associated with severe post-operative pain. Multimodal analgesia facilitates early ambulation and rehabilitation, reduced hospital stay and cost of treatment and increased patient satisfaction.

Aim: To assess the post-operative analgesia in adductor canal block in knee arthroscopy and ccompare the longevity and density of the block in plain ropivacaine with dexmedetomidine and fentanyl as additives.

Methods: In this observational study patients of either sex in the age group of 18-75 years, having body mass index (BMI) of 20-35 kg/m² and belonging to ASA (I & II), who were scheduled to undergo elective knee arthroscopic surgeries were included. A detailed history, thorough physical examination and relevant laboratory investigation were conducted in all patients. On the evening before surgery, the visual analogue scale (VAS) Scoring was explained to all patients. Patients were categorized into three group’s viz. GROUP A: patients received 20ml of 0.2% Ropivacaine + 2ml of Normal Saline (Total 22ml). GROUP B: patients received 20ml of 0.2% Ropivacaine + 0.25mcg/kg of Dexmedetomidine diluted in 2ml of Normal Saline (Total 22ml). GROUP C: patients receiving 20ml of 0.2% Ropivacaine + Fentanyl 1mcg/kg diluted in 2ml of Normal Saline (Total 22ml).

Results: There was no significant difference in demographic profile of the patients among various groups. Difference in the duration of analgesia was statistically significant among the three groups with longest duration in Group C (7.6+1.20 hours) followed by Group B (5.4+1.52 hours) and was least in Group A (4.3+1.70 hours), (p value<0.01). In our study fentanyl (1mcg/kg) has proven to be better than dexmedetomidine (0.25mcg/kg), as we have used a lower concentration of dexmedetomidine. Total consumption of analgesia (Injection Tramadol 1mg/kg, IV) over a period of 24 hours in Group A was 200+28.76mg, Group B was 142+41.53mg and Group C was 108.9+30.64mg. Total quantity of rescue analgesia consumed was maximum in Group A followed by Group B and was least in Group C among the three study groups (P value <0.001).

Conclusion: we conclude that addition of 1mcg/kg fentanyl to ropivacaine showed significantly better duration of postoperative analgesia in comparison to 0.25mcg/kg dexmedetomidine, without causing any significant side effects.