Open Access: View PDF

DOI: http://dx.doi.org/10.21088/ijaa.2349.8471.5818.3

Abstract

Background and Aims: Moxonidine is a selective Imidazoline type 1 receptor agonist. It has a central sympatholytic action and it is used orally as an antihypertensive agent. Selective stimulation of I 1 receptors in the cardiovascular regulatory centers of the medulla oblongata, causes inhibition of central sympathetic activity, leading to a reduction in blood pressure. Laparoscopic procedures are becoming increasingly common in the current era of minimal- access surgeries and anesthesiologists need to be prepared for the perioperative challenges. Creation of pneumoperitoneum causes hemodynamic changes due to increased intra- abdominal pressures and hypercarbia. Several agents have been studied for attenuating the hemodynamic responses to pneumoperitoneum, including antihypertensives, opioids, alpha- 2 agonists, ventilatory strategies and positional alterations. This study aims to analyze the effect of oral Moxonidine premedication in the attenuation of hemodynamic responses during laparoscopic cholecystectomies.

Methods: Sixty ASA grade 1 and 2 patients were randomly selected after ethical approval. Patients were blinded by sealed envelope technique and randomly allocated into one of the two groups to receive either tablet Moxonidine 0.2mg at 8pm the day before surgery and at 8am on the day of surgery (group M, n=30) or placebo, control group (group C, n=30). The anesthesiologist was also blinded about the groups or medications received by the patients.Standard general anesthesia with endotracheal intubation and muscle relaxation was administered. All vital parameters were recorded at different time intervals as before induction (B), after intubation (AI), before pneumoperitoneum (BPN), after pneumoperitoneum (APN), and later at every 10 minutes (APN 10, APN 20, APN 30, APN 40, APN 50, APN 60, APN 90), at release of pneumoperitoneum (RPN), after reversal (AR) and at 15 and 30 minutes after reversal (AR 15 , AR 30 ). Any change in hemodynamic variables more than 20% from the baseline was considered significant. The observations were recorded and subjected to statistical analysis using SPSS statistical software. Student’s ‘t’ test was used for inter-group comparison, with P value < 0.05 considered significant.

Results: The preoperative baseline mean HR was lower in group M (85.90±17.60) as compared to group C (100.90±9.40). The preoperative basal values of mean (±SD) SBP were significantly lower in group M (121.70±10.10) as compared to group C (129.40±6.10). The preoperative basal values of mean (±SD) DBP were significantly lower in study group (78.80±8.30) when compared to control group (86.00±7.30).

Conclusion: Moxonidine is a new generation centrally acting anti-hypertensive, licensed for the treatment of mild to moderate essential hypertension. The use of oral Moxonidine in minimal-access procedures can be recommended as a routine premedication in view of its safety profile.

Keywords : Moxonidine; Hemodynamic Responses; Laparoscopic Cholecystectomy; Imidazoline Receptor; Pneumoperitoneum; Central Sympatholytics.

Corresponding Author : Uma Hariharan [MBBS, DNB, PGDHM, CCEPC, Fellowship Onco-anesthesia & Advanced Regional Anesthesia], Assistant Professor, Dept. of Anesthesiology & Intensive Care, Dr Ram Manohar Lohia Hospital & Postgraduate Institute of Medical Education and Research, Ne