Consumption of Cisatracurium in different age groups, using a closed loop computer controlled system

BACKGROUND: We devised this study to quantify the effect of age on the consumption of cisatracurium under general anaesthesia, using a computer controlled closed loop infusion system. We further investigated this effect on, sufentanil and propofol consumption. METHODS: 74 patients of physical status I and II, requiring general anaesthesia for elective abdominal surgery, were assigned to three groups. Patients in group 1 were aged from 20 to 45, group 2 were from 46 to 64, and group 3 above 65 years old. General Anesthesia was maintained with propofol and muscle paralysis was maintained using a closed-loop computer controlled infusion of cisatracurium. For analgesia, intermittent bolus of sufentanil 10 μg was given. RESULTS: Cisatracurium consumption in group 1, 2 and 3 were 1.8 ± 0.3, 1.6 ± 0.4 and 1.3 ± 0.4 μg/kg/min respectively. There was significant difference of cisatracurium consumption between group 1 and 3 (P = 0.002), and the consumption of cisatracurium in group 3 was less as compared with group 2 (P = 0.04). The average recovery index of patients in group 1, 2 and 3 were 8.8 ± 2.6, 11.5 ± 2.9 and 12.7 ± 2.5 minutes respectively. There were difference between group 1 and 2 (P = 0.02). As compared with group 1, the recovery index was still longer in group 3 (P = 0.001). Patients in group 1, 2 and 3 consumed an average sufentanil 0.4 ± 0.1, 0.4 ± 0.1 and 0.3 ± 0.1 μg/kg/hr, respectively. There were statistical significant between group 1 and 3 (P < 0.0001), and the same trend was found between group 2 and 3 (P = 0.03). The Consumption of propofol in group 1, 2 and 3 were 5.1 ± 0.4, 4.3 ± 0.6 and 3.1 ± 0.5 mg/kg/hr. The difference in the propofol consumption was found statistically significant when comparing between any two groups. CONCLUSION: We concluded that the sensitivity of anesthetic agents increased with age. Less medication was required to achieve a desirable effect in older patients specially those above 65 years of age, and the drug effect was prolonged. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01785446.