The Effect of Deep Block Versus Moderate Block on the Stress Response After Laparoscopic Gastrectomy
Condition: Neuromuscular Blockade
Study type: Interventional
Phase: Phase 4

Summary: 
      This study is a multicenter, randomized, controlled, double-blinded, and parallel design
      study. A total of 96 patients were decided to be recruited considering a 10% dropout rate.
      Patients are randomized to receive a deep block or a moderate block. The randomization
      numbers are generated using a computer-generated randomization code (1) and are sealed in the
      opaque envelope until they are handed over to the anesthesiologist in charge of anesthesia
      management after the induction of anesthesia. Patients, surgeons reporting the scale of
      surgical status, and another researcher analysing the cytokines levels are blinded to the
      patient group. Patients aged 18-65 yr, ASA 1 or 2, and are scheduled for elective
      laparoscopic gastrectomy are included. Patients with severe respiratory or cardiac disease,
      hepatic or renal function impairment, on medications affecting neuromuscular function, and
      with known allergy to the drugs to be used are excluded.
    

Detailed description: 
      Induction and maintenance of anesthesia

      Premedication is done with midazolam 0.03 mg/kg IV at reception area. Anesthesia is induced
      and maintained with intravenous propofol, remifentanil, and rocuronium. The dose of propofol
      is adjusted to maintain BIS value to 40-60, remifentanil to maintain blood pressure within
      20% of preoperative value, and rocuronium to maintain PTC 1-2 (deep block) or TOF1-2
      (moderate block). The monitoring consists of ECG, NIBP, pulse oximetry, temperature, ETCO2,
      BIS, and neuromuscular monitoring with acceleromyography (TOF-Watch SXTM, Organon Ltd.,
      Dublin, Ireland).

      Management and monitoring of neuromuscular block

      After induction of anesthesia, continuous neuromuscular monitoring is started after
      calibration and stabilization of the signal as recommended by good clinical research
      practice; 50 Hz tetanic stimulation for 5 s, calibration, stabilization for at least 2 min 2.
      After stabilization, rocuronium 0.6 mg/kg is administered IV within 5 s for tracheal
      intubation. Maintenance dose of 0.1-0.2 mg/kg rocuronium is administered as needed for the
      maintenance of PTC1-2 (deep block) or TOF1-2 (moderate block). At the end of surgery,
      sugammadex 4 mg/kg for deep block group or neostigmine 50 ㎍/kg with glycopyrrolate 10 ㎍/kg
      for moderate block group are administered IV for reversal of neuromuscular block.

      Evaluation of surgical conditions

      A 5-point surgical rating scale (1 = excellent, 2 = good, 3 = acceptable, 4 = poor, 5 =
      extremely poor) is rated by the surgeon who is in charge of the patient's operation and is
      blind to the patient's group assignment. Intraoperative patient movement reported by surgeon,
      checked by restoration of spontaneous respiration or sudden increase in PIP, and any other
      movement are also recorded.

      Measurement of cytokines and acute phase reactants

      Blood samples are collected from the antecubital vein of the arm not used for IV infusion
      preoperatively, at the end of peritoneal closure, and 1, 2, & 48 hr after the end of
      operation for analysis of TNF-α, IL-1β, 6, 8 and CRP. The blood samples are collected at test
      tubes and sent to the laboratory on ice. Cytokines are analyzed with enzyme-linked
      immunosorbent assay and CRP is determined by an institutional chemistry analyzer.

      Postoperative pain measurement

      Postoperative pain is evaluated by verbal numerical rating scale (VNRS, 0 = no pain, 10 = the
      severest pain imaginable) at postoperative 1, 2, 6, 24, and 48 hr. Postoperative pain is
      controlled by IV patient controlled analgesia using fentanyl. If patient complain of severe
      pain (VNRS score of 7 or more), additional analgesics can be used according to the attending
      physician. The amount of fentanyl used and additional analgesic drugs used are reported.
    

Intervention name(s): deep block
Intervention type(s): Drug
Intervention description(s): sugammadex 4 mg/kg are administered IV for reversal of neuromuscular block
Other intervention name(s): bridion
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Other
Keywords: Neuromuscular blockade; Sugammadex; Laparoscopic surgery; IL-6