Macintosh Versus GlideScope Versus C-MAC for Double Lumen Endotracheal Intubation
Condition: Thoracic
Study type: Interventional

Summary: 
      The double lumen endotracheal tube (DLT) is the most widely-used device for single lung
      ventilation in current thoracic anesthesia practice. In recent years, the routine application
      of the videolaryngoscope for single lumen endotracheal intubation has increased; nevertheless
      there are few studies of the use of the videolaryngoscope for DLT. The authors wondered
      whether there were benefits to using the videolaryngoscope for DLT placement in patients with
      predicted normal airways. Therefore, this study was designed to compare the performances of
      the GlideScope®, the C-MAC®(D) videolaryngoscope and the Macintosh laryngoscope in DLT
      intubation.
    

Detailed description: 
      Patients randomly assigned into Macintosh group, GlideScope (Verathon Medical, Bothwell, UT,
      USA) group, or CMAC(D) (Karl Storz GmbHand Co.KG, Tuttlingen, Germany) group. This will be
      done using a closed envelope technique using a computer-generated block randomization method.
      Before the study, the computerized randomization will be performed and the allocation results
      will be placed in individual numbered and sealed envelopes. Patients remained blinded about
      their intubation technique until post-operative assessment was completed. The researcher
      responsible for recruitment will be blinded to the allocation result. After a patient will be
      consented for the study, allocation will be revealed. All endotracheal intubations will be
      performed by fthe same anesthesiologist with 10 years' working experience skilled in
      videolaryngoscopy. Left-side or right-side 32Fr/35Fr Mallinckrodt™ DLTs (Mallinckrodt
      Medical, Athlone, Ireland) will be selected for female patients and 35Fr/37Fr DLTs for male
      patients depending on whether their heights were below or above 155 cm for females and 165 cm
      for males. If the operation side will be the left, right-side DLT will be used; otherwise,
      the left-side DLT will be used. To facilitate intubation, the distal 10-12 cm concavity of
      the DLT (with the stylet in situ) will be molded along the blade convexity in each group. The
      tracheal and the bronchial cuffs of the DLT tubes will be lubricated with sterile Surgilube.
      No premedication will be given before induction. Standard monitoring prior to induction
      included ECG, invasive arterial blood pressure, SpO2, and end-tidal carbon dioxide. After
      pre-oxygenation with 100% oxygen, anesthesia will be induced with intravenous midazolam 0.05
      mg. kg- 1 , propofol 1.5 mg. kg- 1 , fentanyl 5 μg. kg- 1 , and rocuronium 0.6 mg. kg- 1 .
      Two minutes after rocuronium administration, DLT intubation will be performed using the
      allocated laryngoscope. The DLT will be inserted with the distal concavity facing anteriorly
      until the bronchial lumen cuff passed the vocal cords. The stylet will be then removed, and
      rotation will be performed while tube will be advanced. The left DLT rotated 90°
      counter-clockwise, and the right DLT will be rotated 90° clockwise to enter the respective
      mainstem bronchus. The number of intubation attempts, ease of laryngoscopy insertion, Quality
      of view, Assist maneuvers, Intubation difficulty will be recorded. Hemodynamic changes will
      be monitored during induction. If systolic blood pressure fell below 80 mmHg, ephedrine 5 mg
      will be administrated intravenously. Atropine 0.5 mg will be given for heart rate below 50
      beats per minute. After the tip of the DLT was located in the targeted bronchus, the tracheal
      cuff will be inflated and ventilation of the lungs started. Fiberoptic bronchoscopic
      assessment of adequate bronchial cuff placement will be followed by DLT placement. DLT
      insertion time will be defined as from the time the laryngoscope passed the patient's lips
      until three complete end-tidal carbon dioxide cycles were displayed on the monitor.
      Intubation success rate at the first attempt will be recorded by the same observer. The
      difficulty of DLT insertion and delivery will be assessed by the operator, using NRS ranging
      from 0 to 10. The NRS results will be grouped as 0 = none, 1-3 = mild, 4-6 = moderate, and
      7-10 = severe. C/L degrees were classified as four degrees (I, IIA, IIB, and III) and will be
      assessed by the same operator. If the degree will be not class I, external laryngeal pressure
      will be provided by an assistant. Time required to successful intubation. Intubation time is
      defined as the time taken for insertion of the blade between the teeth till the tracheal tube
      cuffٴ passed through the vocal cords. Failure of intubation was defined as any intubation
      attempt of >120 s or inability to intubate. Number of intubation attempts, Ease of
      laryngoscope insertion, Quality of view by Cormack and Lehane grade . Assist maneuvers.
      Intubation difficult score indicates the degree of difficulty of intubation using 7
      parameters (0=easy intubation, 0 ˂IDS≤5 =slight difficulty, 5 < IDS =moderate to major
      diffculty, IDS= ∞ impossible intubation) . The time taken for fiberoptic bronchoscopy was
      defined as the time from endobronchial intubation to placement confirmation using fiberoptic
      bronchoscopy. The operators examined blade surfaces for blood after removal. Hemodynamic
      parameters (mean arterial blood pressure and heart rate) will be recorded 10 min before
      induction and 1, 3, and 5 min after intubation. After the assessment by fiberoptic
      bronchoscopy, the oral cavity, pharynx, larynx and teeth will be examined for signs of
      laceration or bleeding by an independent investigator who will be unaware of the type of
      laryngoscope used. One day after surgery, an independent investigator will interview patients
      to assess the presence of sore throat and hoarseness of voice.
    

Intervention name(s): Intubation of the double lumen tube by Macintoch laryngoscope; Intubation of the double lumen tube by Glidescope videolaryngoscope; Intubation of the double lumen tube by C-MAC®(D) videolaryngoscope
Intervention type(s): Device; Device; Device
Intervention description(s): After induction of anesthesia insertion of the double lumen tube was done by Macintosh laryngoscope; After induction of anesthesia insertion of the double lumen tube was done by GlideScope® videolaryngoscope; After induction of anesthesia insertion of the double lumen tube was done by C-MAC®(D) videolaryngoscope
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: Patients randomly assigned into Macintosh group, GlideScope (Verathon Medical, Bothwell, UT, USA) group, or CMAC(D) (Karl Storz GmbHand Co.KG, Tuttlingen, Germany) group. After pre-oxygenation , anesthesia will be induced with intravenous midazolam 0.05 mg. kg- 1 , propofol 1.5 mg. kg- 1 , fentanyl 5 μg. kg- 1 , and rocuronium 0.6 mg. kg- 1 . . The DLT will be inserted with the distal concavity facing anteriorly until the bronchial lumen cuff passed the vocal cords. The stylet will be then removed, and rotation will be performed while tube will be advanced. The left DLT rotated 90° counter-clockwise, and the right DLT will be rotated 90° clockwise to enter the respective mainstem bronchus.
Masking: Single (Participant)
Primary purpose: Other
Keywords: Macintosh; laryngoscope; GlideScope; C-MAC; videolaryngoscope; double lumen tube