Premium
Effect of low‐dose ketamine on MAC BAR of sevoflurane in laparoscopic cholecystectomy: A randomized controlled trial
Author(s) -
Chen Changchun,
Pang Qiying,
Tu Ailing,
Wang Ji,
Tu Faping
Publication year - 2021
Publication title -
journal of clinical pharmacy and therapeutics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.622
H-Index - 73
eISSN - 1365-2710
pISSN - 0269-4727
DOI - 10.1111/jcpt.13263
Subject(s) - sevoflurane , ketamine , anesthesia , medicine , pneumoperitoneum , cholecystectomy , intubation , randomized controlled trial , laparoscopic cholecystectomy , surgery , laparoscopy
What is known and objective Low‐dose ketamine can reduce the minimum alveolar concentration of sevoflurane necessary to block the adrenergic response (MAC BAR ) in animals. However, the effects of low‐dose ketamine on the sevoflurane MAC BAR in patients undergoing laparoscopic surgery are unclear. The aim of this study was to investigate the effects of three different low doses of ketamine on the MAC BAR of sevoflurane in patients undergoing laparoscopic cholecystectomy. Methods One hundred patients who underwent laparoscopic cholecystectomy were enrolled. After general anaesthesia induction and tracheal intubation, patients received sevoflurane anaesthesia in combination with a loading dose of saline followed by infusion or a loading dose of 0.5 mg/kg ketamine followed by a continuous infusion of 5 (K 1 group), 10 (K 2 group) and 20 μg/kg/min (K 3 group). The target concentration of end‐tidal sevoflurane was maintained for at least 20 minutes before carbon dioxide pneumoperitoneum stimulus. The MAC BAR of sevoflurane in each group was determined by using an up‐and‐down sequential allocation technique. Results and discussion Seventy‐one patients completed the study. The values of MAC BAR for sevoflurane were 5.3% in the K 0 , 4.8% in K 1 , 3.3% in K 2 and 3.2% in K 3 groups. The use of ketamine significantly reduced the MAC BAR of sevoflurane compared to sevoflurane alone. The K 2 and K 3 groups showed significantly lower values of MAC BAR than that in the K 1 group. However, a higher dose of ketamine in the K 3 group did not further reduce the sevoflurane MAC BAR . The mean arterial blood pressure (MAP) values before pneumoperitoneum in the K 2 and the K 3 groups were significantly higher compared to those in the K 0 and K 1 groups. Compared with the values before pneumoperitoneum, the heart rate and MAP after pneumoperitoneum were significantly increased. Overall, the haemodynamics remained stable during the study period in all groups. What is new and conclusion A loading dose of 0.5 mg/kg ketamine followed by a continuous infusion of 10.0 μg/kg/min led to a significant decrease in the MAC BAR of sevoflurane in patients undergoing laparoscopic cholecystectomy.