Clinical Trial: Remifentanil Without Muscle Relaxant for Thoracotomy

Study Status: Completed
Recruit Status: Completed
Study Type: Interventional

Official Title: Target-Controlled Infusion of Remifentanil Without Muscle Relaxant Allows Acceptable Surgical Conditions During Thoracotomy

Brief Summary:

Although the administration of muscle relaxation is essential standard of care for thoracic procedures, it could cause long-reversal times and postoperative residual curarization (PORC) increasing length of post-anesthesia care unit (PACU) stay and hospital costs. Sugammadex offers new perspectives to reduce the incidence of PORC. Unfortunately it is not available in many countries because of its significantly high cost. We hypothesized that the use of target-controlled remifentanil infusion (TCI) with the non-muscle relaxant (NMR) would be associated with comparable surgical conditions and reduced total costs compared with the use of neuromuscular blockers during thoracotomy.

After ethical approval, 66 patients scheduled for elective thoracotomy under sevoflurane anesthesia with TCI remifentanil will be included in this prospective, randomized, single-blind, controlled study.

Patients will be randomly assigned to receive cisatracurium or saline (n = 33 for each group) throughout the procedure. Laryngoscopy and intubating conditions, intraoperative modified thoracic surgery rating scale (Table below), incidence of light anesthesia, and use of vasopressors and anesthetics, clinical recovery, incidence of PORC, PACU and hospital stays, and total costs will be recorded.


Detailed Summary:

Administration of muscle relaxation is essential standard of care in thoracic surgery as it causes an improvement of surgical conditions. The concept of "Fast-track thoracic anesthesia" requires the use of either short or intermediate-acting nondepolarising neuromuscular blocking drugs, to provide a sufficient neuromuscular blockade during surgery and to restore the normal neuromuscular transmission immediately at the end of surgery.1

However, long-reversal times and postoperative residual curarization (PORC) are still a problem in 30%-60% of the anesthetized patients even with the use of new intermediate-acting neuromuscular blockers.2-3 PORC could cause aspiration of the lungs and respiratory failure4 after thoracic surgery that may prolong the post anesthesia care unit (PACU) and hospital stays.

Although, sugammadex, a modified gamma-cyclodextrin, offers new perspectives to reduce the incidence of PORC,4 it is not available in many countries because of its significantly high cost.5

Therefore, in fast-track cardiac surgery, it seems unnecessary to maintain paralysis by repetitive bolus injection or continuous infusion of neuromuscular blockers with overall surgeons' satisfaction.6

The use of remifentanil without muscle relaxants provides excellent intubating conditions and short recovery duration.7 The effective concentration range of remifentanil for tracheal intubation without muscle relaxant is 4.5-5.5 ng/ml.8 The use of non-muscle relaxant (NMR) anesthetic techniques using remifentanil with either propofol or sevoflurane allows early extubation after trans-sternal or video-assisted thymectomy in myasthenic patients.9-10

The use of NMR technique on the surgical
Sponsor: Dammam University

Current Primary Outcome: Modified surgical rating scale [ Time Frame: for 3 hours after start of surgery ]

A four-point ordinal scale adopted from the surgical rating scale of Martini et al.,ranging from 1 (extremely poor conditions) to 4 (optimal conditions).

Extremely poor (Score 1) indicates that the surgeon is unable to work because of coughing, bucking, diaphragmatic contractions or movements, or the inability to spread or approximate the ribs during chest opening and closure, respectively, because of inadequate muscle relaxation;

poor (Score 2) indicates that there is a visible field, but the surgeon is severely hampered by continuous muscle contractions, spontaneous movements of the surgical lung, or both that could cause hazard of tissue damage;

good (Score 3) indicates that there is an acceptable field with sporadic muscle contractions causing some interference with the surgeon's work;

excellent (Score 4) indicates a wide working field without any lung movement or muscle contractions.



Original Primary Outcome: Same as current

Current Secondary Outcome:

  • heart rate [ Time Frame: 5 min after induction of anesthesia, 1 min after chest opening, 30 min after start of surgery, 60 min after start of surgery, 90 min after start of surgery, 120 min after start of surgery, 1 min after start of chest closure, 5 min after extubation ]
    heart rate
  • Mean blood pressure [ Time Frame: 5 min after induction of anesthesia, 1 min after chest opening, 30 min after start of surgery, 60 min after start of surgery, 90 min after start of surgery, 120 min after start of surgery, 1 min after start of chest closure, 5 min after extubation ]
    Mean blood pressure
  • Train-of-four ratio [ Time Frame: 5 min after induction of anesthesia, 1 min after chest opening, 30 min after start of surgery, 60 min after start of surgery, 90 min after start of surgery, 120 min after start of surgery, 1 min after start of chest closure, 5 min after extubation ]
    Train-of-four ratio
  • laryngoscopy conditions [ Time Frame: 1 min after laryngscopy ]
    laryngoscopy conditions
  • intubating conditions [ Time Frame: 1 min after intubation ]
    intubating conditions
  • Cost of medications [ Time Frame: after surgery ]
    cost of the used medications
  • Need for vasoactive drugs [ Time Frame: for 3 hour during surgery ]
    use of ephedrine, and norepinephrine
  • Recovery Times [ Time Frame: for 1 hours after surgery ]
    the times to spontaneous eye opening, obey verbal command, tracheal extubation and post-anesthesia care unit discharge


Original Secondary Outcome: Same as current

Information By: Dammam University

Dates:
Date Received: January 7, 2014
Date Started: January 2014
Date Completion:
Last Updated: September 8, 2014
Last Verified: September 2014