The Effect of Deep Neuromuscular Blockade on Requirement of Intravenous Anesthetic Agent

The Effect of Deep Neuromuscular Blockade on Requirement of Intravenous Anesthetic Agent During Laparoscopic Colorectal Surgery

Recently, deep neuromuscular blockade during general anesthesia has been studied by many authors regarding various effects upon patients' outcomes and surgical conditions. We believe deep neuromuscular blockade can be especially beneficial in laparoscopic surgery, because it can expand surgical space and prevent patients' minute movements that can disturb precise operations. In clinical situations, anesthetists tend to compensate the insufficiency of neuromuscular blockade by increasing the dose of other anesthetic agents, which can prolong patients' recovery time and impair the surgical condition. In this study, we plan to divide the patients into 2 groups according to the depth of neuromuscular blockade, and compare the dose of anesthetic agent used to maintain surgical condition.

Patients undergoing elective laparoscopic colorectal surgery are going to be recruited and divided into 2 groups: Group D will receive deep neuromuscular blockade, and Group M will receive moderate neuromuscular blockade using continuous infusion of rocuronium. Acceleromyography(TOF-watch SX) will be used to monitor the depth of blockade. In both groups, the anesthesia will be maintained with TIVA(total intra-venous anesthesia) including continuous target-controlled infusion of propofol and remifentanil. During the surgery, the number of patient movement and restoration of self respiration will be recorded. At the end of anesthesia, the dose of propofol and remifentanil used will be assessed and compared between the groups. Also, the satisfaction score of surgeons regarding the surgical condition, the anesthesia time, the operation time will be documented. After the patients are discharged, their charts are going to be reviewed and whether any pulmonary or surgical complications occurred will be documented.

Inclusion Criteria:

• Patients undergoing elective laparoscopic colorectal resection due to benign or malignant neoplasm of colon or rectum
• ASA class I or II

Exclusion Criteria:

• Patients receiving medications known to have drug-drug interaction with neuromuscular blocking agents
• Patients who have significantly impaired cardiac, pulmonary, hepatic, renal function
• Patients who are pregnant
• Patients who are known to have hypersensitivity to the anesthetic/analgesic/neuromuscular blocking agents which are going to be used in the study
• BMI < 18.5 or > 35.0 kg/m2
• Patients with previous history of open abdominal surgery
• Patients with previous history of malignant hyperthermia