Effect of 6% Hydroxyethyl Starch Pre-Administration for Reduction of Pain on Propofol Injection: A Randomized Controlled Trial

Background: Pain on propofol injection has been a matter of concern over the years. However, even with multi-modal techniques, pain on propofol injection is not abolished completely. Colloids modify the vascular endothelium and prevent contact activation of various substances. Pre administration of colloids may prevent contact activation of vascular endothelium by propofol. Aims and Objectives: To study the effect of 6% HES on the incidence of pain on propofol injection, and occurrence of any adverse reaction. Materials and Methods: This double blinded randomized study included 68 patients of the ASA I and II patients and 18-65 years old who underwent elective surgery. The patients were randomised into two groups: who received either 100ml bolus of 6% HES (n=34) or 100 mL bolus of placebo 0.9% normal saline (n=34). Comparison of demographic characteristics, pain during propofol injection, and adverse effects was done. P-value <0.05 was considered statistically significant. Results: Both groups had similar age, gender, ASA, and weight distribution. Compared to Group B, Group A has a statistically comparable propofol dose distribution (Mean &plusmn; SD: 102.79 &plusmn; 31.6 mg vs 103.68 &plusmn; 31.07 mg, p=0.908). In terms of heart rate compared to placebo, HES group had comparable heart rate before induction at 1, 2, 3, and at 4 minutes. SBP, DBP, and respiratory rate were also comparable. Compared to placebo group, HES group showed significant lesser pain at 10 seconds (0.29 &plusmn; 0.58 vs. 1 &plusmn; 0.98, p = 0.001); at 20 seconds (0.18 &plusmn; 0.46 vs. 0.85 &plusmn; 0.89, p = 0.0003); and at 30 seconds (0.12 &plusmn; 0.41 vs. 0.59 &plusmn; 0.66, p = 0.0003). There were no significant adverse effects in any group. Conclusion: It can be concluded that 6% HES is efficacious and safe for controlling pain on propofol injection. It brings about a significant reduction in the pain as assessed by VAS at various time points without causing any significant side effects.