A Comparative Study of Glidescope Versus Macintosh Laryngoscope in Adult Hypertensive Patients
Condition: Hypertensive Patients
Study type: Interventional

Summary: 
      Hemodynamic response to laryngoscopy and tracheal intubation remain of utmost concern in
      anesthesia practice. Sympathetic stimulation and adverse physiologic events could be
      tolerated by healthy individuals, but they may be detrimental in hypertensive patients.

      The magnitude of hemodynamic response of intubation is related to the degree of manipulation
      of the oropharyngeo-laryngeal structures. Unlike Macintosh laryngoscope,Glidescope is a
      device that does not require alignment of oropharyngeal axis to visualize the glottis.It
      needs less upward lifting force with less manipulation of pharyngeal structures during the
      intubation.

      It was reported that Glidescope had no significant advantage over Macintosh in attenuating
      circulatory response to endotracheal intubation in normotensive patients.Till now no clinical
      trials investigate the hemodynamic effects of Glidescope in hypertensive patients.The
      investigators hypothesized that the Glidescope will induce less hemodynamic changes among
      hypertensive patients during endotracheal intubation.So the study was designed to compare
      effects of Glidescope versus Macintosh laryngoscope in hypertensive patients with special
      regard to hemodynamics and intubation conditions.
    

Detailed description: 
      This is prospective randomized study will performed at Urology and Nephrology Centre,
      Mansoura University after approval from Institutional Research Board, Mansoura
      University.Patients were interviewed and written informed consent will be obtained from
      selected patients scheduled for different urological surgeries.

      Eligible adult patients will be randomly allocated by a computer-generated randomization
      sequence into 2 equal groups:

      Macintosh group: 45 patients will be intubated by Macintosh laryngoscope(Group M).

      Glidescope group: 45 patients will be intubated by Glidescope(Group G).

      Preoperative assessment:

      All patients will be assessed preoperatively by:

        1. History taking (for medical and surgical history)

        2. Physical examination (including heart, blood pressure, electrocardiogram, chest
           auscultation and difficult airway assessment)

        3. Laboratory investigation (complete blood picture, renal and liver function tests and
           bleeding profile).

      The day before surgery, the study protocol will explained to all patients and the patients
      will fast for 6 hours before the surgery. All the patients will receive their
      antihypertensive medications till the morning of surgery

      On arrival to the operation room:

      Routine monitoring including: electrocardiogram, non-invasive blood pressure and pulse
      oximetry will be set, Peripheral intravenous cannula will be inserted and acetated Ringer
      will be started at rate of 4ml/kg/h.

      Anesthetic management:

      The induction will be similar in both groups; Pre-oxygenation for 5 minutes will be done in
      all patients and then they will receive 0.02 mg/Kg midazolam, 1μg/Kg fentanyl, 2mg/kg
      Propofol slowly until loss of verbal contact and rocurronium 0.6 mg/kg intravenously.Till the
      establishment of adequate neuromuscular block, the patients' ventilation will be assisted
      manually using a face mask. During this period the patients' lungs will be ventilated with
      100% oxygen.

      After establishment of adequate neuromuscular block after 3 minutes, the trachea will be
      intubated using either glidescope or Macintosh laryngoscope.The patient will be intubated by
      suitable sized tube (in males 8 mm and in females 7.5 mm internal diameter). In Macintosh
      group we will use a blade size 3, the laryngoscope will be advanced in patient mouth
      displacing the tongue laterally till the laryngoscope reach the vallecula and then gentle
      lifting will be applied till visualization of the laryngeal inlet then the tube will be
      advanced.For endotracheal intubation with glidescope, size 3 blade will be used in all of the
      cases. Glidescope will be advanced gently in the oral cavity (in the midline) and walked down
      the tongue. The scope will be further advanced into the vallecula and gentle lifting force
      will be applied for visualization of the glottis. Endotracheal tube will be loaded on
      specific rigid stylet with 60 degree bent and will be advanced into the trachea by the same
      operator.

      External pressure to the front of the neck will be applied on request of the operator by
      another anesthetist.After placement of the endotracheal tube, the cuff of the tube will be
      inflated gradually with and the chest will be auscultated to ensure proper tracheal
      positioning and to exclude bronchial intubation and then the tube will be fixed.

      All the intubations will be performed by a well-trained anesthetist. The intubation attempt
      failure will be defined when the intubation time exceed 120 seconds, esophageal intubation
      occurred or desaturation with arterial oxygen saturation dropped below 90%. Three attempts
      will only allow,then anesthesia will be carried out according to decision of the attending
      anesthetist with exclusion of the case from the study. Face-mask intermittent positive
      pressure ventilation will be carried out in-between the attempts.

      The intubation condition will be assessed using first attempt success rate, number of
      attempts, intubation time and Cormack Lehane score. The intubation time is defined as the
      period from termination of face mask oxygenation till the appearance of carbon dioxide trace
      after positive pressure ventilation.

      Cormack Lehane score is based on the laryngoscopic view as following: grade 1 full view of
      the glottis, grade 2 partial view of the glottis, grade 3 only the epiglottis appear and
      grade 4 neither the glottis nor the epiglottis appear

      Monitoring:

      Systolic, diastolic, mean arterial blood pressure and heart rate will be recorded at the
      following time points: T1: before anesthesia, T2: after induction and immediately before
      intubation, T3: immediate after completion of intubation, T4: after 1 minute of intubation,
      T5: after 2 minutes of intubation, T6: after 3 minutes of intubation, T7: after 5 minutes of
      intubation, T8: after 10 minutes of intubation.Maximal blood pressure and heart rate changes
      will be recorded

      Postoperative follow up:

      The patient will be assessed 24 hours postoperatively for the sore throat and hoarseness of
      voice according to the 4-point score
    

Intervention name(s): Glidescope; Macintosh
Intervention type(s): Device; Device
Intervention description(s): The patient will be intubated by suitable sized tube (in males 8 mm and in females 7.5 mm internal diameter).
For endotracheal intubation with glidescope, size 3 blade will be used in all of the cases. Glidoscope will be advanced gently in the oral cavity (in the midline) and walked down the tongue. The scope will be further advanced into the vallecula and gentle lifting force will be applied for visualization of the glottis. Endotracheal tube will be loaded on specific rigid stylet with 60 degree bent and will be advanced into the trachea by the same operator.
Systolic, diastolic, mean arterial blood pressure and heart rate will be recorded at the following time points: T1: before anesthesia, T2: after induction and immediately before intubation, T3: immediate after completion of intubation, T4: after 1 minute of intubation, T5: after 2 minutes of intubation, T6: after 3 minutes of intubation, T7: after 5 minutes of intubation, T8: after 10 minutes of intubation.; The patient will be intubated by suitable sized tube (in males 8 mm and in females 7.5 mm internal diameter). In Macintosh group we will use a blade size 3 at first. The laryngoscope will be advanced in patient mouth displacing the tongue laterally till the laryngoscope reach the vallecula and then gentle lifting will be applied till visualization of the laryngeal inlet then the tube will be advanced.Systolic, diastolic, mean arterial blood pressure and heart rate will be recorded at the following time points: T1: before anesthesia, T2: after induction and immediately before intubation, T3: immediate after completion of intubation, T4: after 1 minute of intubation, T5: after 2 minutes of intubation, T6: after 3 minutes of intubation, T7: after 5 minutes of intubation, T8: after 10 minutes of intubation.Maximal arterial blood pressure and heart rate changes will be recorded
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: Eligible 90 adult patients will be randomly allocated by a computer-generated randomization sequence into 2 equal groups:
Macintosh group: 45 patients will be intubated by Macintosh laryngoscope (Group M).
Glidescope group: 45 patients will be intubated by Glidescope (Group G).
Masking: Single (Participant)
Primary purpose: Other
Keywords: Glidescope,Macintosh, Laryngscope, intubation,Hypertension.