Background:

Ondansetron and Dexmedetomidine are recently used effectively in preventing shivering following spinal anesthesia.

Aim: comparing the effect of weight adjusted dose of Ondansetron and Dexmedetomidine in preventing post spinal shivering and its subsequent hazards in cases who undergone elective transurethral resection of Prostate (TURP).

Methods:

In this prospective randomized double blind controlled trial, 132 ASA (1, II) patients, who were scheduled to undergo (TURP), divided into 3 equal groups (44 each): Control group: received 5ml normal saline (0.9 %) intravenously after SA, Group D: received (1ug/kg) Dexmedetomidine intravenously diluted in 5ml normal saline after SA, Group O: received (0.1mgl/kg) Ondansetron intravenously diluted in 5ml normal saline after SA. Shivering occurrences, intensity and duration (primary outcome), hemodynamics & core temperature changes, sedation level, total consumed rescue pethidine and intraoperative complications were evaluated.

Results:

There was statistically non-significant difference between Ondansetron and Dexmedetomidine as regard to shivering occurrences, intensity and duration while it was significant when compared to Control group, hemodynamics were significant decrease in heart rate in Dexmedetomidine while compared to Ondansetron and Control groups. Additionally, sedation level was significantly increased in Dexmedetomidine group while compared to other groups. However, there was significant increase in total consumed rescue pethidine in Control group when compared to other groups. When compared to both the Dexmedetomidine and control groups, the Ondansetron group had a significantly lower risk of hypotension.

Conclusion: IV weight adjusted dose of Ondansetron is associated with more hemodynamic stability compared to IV Dexmedetomidine with fewer incidences of bradycardia and hypotension