Effect of ringer lactate preloading on induction dose requirement of propofol and its haemodynamic stability at a tertiary center

Abstract

Abstract: Background The induction of anaesthesia is a critical step in the management of patients undergoing surgical procedures. Propofol is a commonly used anaesthetic agent due to its rapid onset and short duration of action, making it ideal for procedures. However, Propofol administration can result in significant hypotension, which can be detrimental to haemodynamic stability. Ringer lactate is a crystalloid solution commonly used for volume replacement in perioperative settings.

Objective:

To evaluate the effect of Ringer lactate preloading on the induction dose requirement of Propofol and its haemodynamic stability at a tertiary center.

Methodology:

This study was a hospital-based comparative study conducted for one year (1st April 2023 to 31st March 2024) after obtaining ethical clearance from the Institutional Review Committee of the National Medical College (PG-NMC/565/079-080), Nepal Health Research Council (519/2022 MT) and also registered at ClinicalTrials.gov (NCT05777135). A total of 60 patients were selected in the study and allocated into two groups of 30 each (Group I and Group II) by ballot method and patient code was given. Group I (n = 30) preloading with Ringer lactate 10 ml/kg over 30 minutes before surgery was done and the Propofol dose requirement for induction of anaesthesia with visualization of loss of eyelash reflex was noted. In Group II (n = 30) no preloading was done and the Propofol dose requirement for induction of anaesthesia with visualization of loss of eyelash reflex was noted. The effect (heart rate, systolic blood pressure, diastolic blood pressure and mean arterial pressure) was recorded in both groups.

Results: The mean dose of Propofol required for induction was significantly lower in Group I preloading 1.80 ± 0.18 mg/kg compared to Group II without preloading 2.46 ± 0.44 mg/kg with a P value of < 0.001 which was statistically highly significant. Propofol dose required to achieve the loss of eyelash reflex in Group I (17.17 ± 4.67 seconds) compared to Group II (21.50 ± 5.74 seconds), with a P value of 0.002. Haemodynamic stability, as indicated by heart rate and mean arterial pressure, was better maintained in the preloading group, suggesting that Ringer lactate contributes to improved haemodynamic stability during induction. Although the incidence of coughing and involuntary movements was not statistically significant between groups, the overall reduction in Propofol requirement was notable.

Conclusion:

These findings support the routine use of Ringer lactate preloading to optimize Propofol dosing and maintain haemodynamic stability, potentially improving patient safety and cost-effectiveness in clinical practice. Preloading with Ringer lactate significantly reduces the induction dose of Propofol required to achieve the loss of eyelash reflex and enhances haemodynamic stability during anaesthesia induction. Further studies with larger sample sizes and diverse patient populations are recommended to confirm these results and refine anaesthesia protocols.