COMPARATIVE STUDY OF CRITICAL MOMENT HYPOTENSION VERSUS CONTROLLED HYPOTENSION ON INTRA-OPERATIVE BLOOD LOSS DURING BILATERAL SAGITTAL SPLIT OSTEOTOMY SURGERY: A RANDOMIZED CONTROLLED TRIAL

Abstract

Introduction:  Despite the fact that orthognathic surgery is generally regarded as safe, it does result in significant blood loss. Numerous pharmacological and non-pharmacological approaches have been utilised to address this issue. Controlled hypotensive anaesthesia administered throughout surgery and critical moment hypotension anaesthesia administered at a specific time, such as during the LeFort down fracture or the Sagittal Split, have both been used effectively to limit blood loss. There is currently no research that contrasts these two techniques to determine which is more applicable at minimising the loss of blood throughout the procedure of orthognathic surgery.; however, numerous authors have examined the use of both procedures. This study's objective is to compare the effects of general versus critical moment hypotension anaesthesia on the loss of blood throughout the procedure of orthognathic surgery.

Materials and methods- Eighteen adults with dentofacial deformities necessitating the orthognathic procedure Bilateral Sagittal Split Osteotomy were considered. They were split into three categories using a simple randomization strategy. Throughout the operation, Group I received a 10mg/kg body weight intravenous infusion of controlled hypotension anaesthesia. Group II received normotensive anaesthesia during surgery, while Group III received critical moment hypotension anaesthesia. Blood loss is estimated by calculating the total amount of blood suctioned, excluding saline solution and gauze saturated with blood.  Also compared were haemoglobin and hematocrit levels before and after surgery.

Results-There were no statistical significant disparities between the sexes in hematocrit, surgical duration/time, bleeding/blood loss, or HB loss. Age was found to have a weak negative correlation (-0.19) with postoperative blood loss and hematocrit decrease (-0.30). There was no significant disparity among the interventions' total durations/time taken for surgery. There were statistically significant disparities in postoperative loss of blood, Hb loss, and haematocrit decrease between the groups. Loss of blood was found to correlate positively with hematocrit and Hb loss, whereas hematocrit loss was found to correlate positively with hematocrit loss. In the controlled hypotension group, mean blood loss was less than in the critical moment hypotension group.

Conclusion-Both critical moment hypotension anaesthesia and controlled hypotension anaesthesia are superior to full normotensive anaesthesia for minimising intraoperative blood loss. In addition, the effectiveness of critical moment hypotension anaesthesia was comparable to that of controlled hypotension anaesthesia. Therefore, it is possible to reduce the use of controlled hypotension anaesthesia in orthognathic surgeries

Keywords: Bilateral sagittal split surgery, Quality of life, hypotension anesthesia , Blood loss.