Please select the eligibility criteria that correspond to the clinical trial below.
Title: Comparison of McGrath Videolaryngoscopy and Direct Laryngoscopy for Intubation in Patients With Morbid Obesity in Non-cardiac Surgery
Brief Summary: Our goal is to compare conventional direct laryngoscopy using a Macintosh blade with the McGrath videolaryngoscope for endotracheal intubation in very morbidly obese patients undergoing non-cardiac surgery. Specifically, we propose to test the primary hypotheses that videolaryngoscopy improves visualization of the vocal cords, defined with modified Cormack and Lehane classification, compared to direct laryngoscopy.


Options:
A: Inclusion Criteria:

* After signing of the informed consent,
* ASA physical status I and II
* Mallampati class 1\& 2,
* BMI \< 35,
* Undergoing elective surgical procedures (not exceeding two hours in duration) requiring ET intubation

Exclusion Criteria:

* Patients undergoing day case,
* bariatric, cardiac, nasal, oral or head \& neck surgeries,
* requiring placement of throat pack or nasogastric/ orogastric tube,
* patients assigned to rapid sequence induction,
* hoarseness,
* patients with anticipated difficult intubation,
* history of recent upper respiratory tract infection,
* history of difficult intubation
* psychiatric disorders hindering proper evaluation,
* use of steroids (oral or inhalational) or non-steroidal anti-inflammatory drugs within one week of surgery or previous surgery within last two weeks
B: Inclusion Criteria:

* ASA status I or II
* Mallampati class I or II
* Patients \> 18 years old
* Elective general, gynecological, neurological, orthopedic, plastic or urological surgery under general anesthesia
* Type of surgery that usually necessitate endotracheal intubation and controlled ventilation

Non-inlusion Criteria:

* Patient refusal
* History of psychiatric diseases or psychological problems (including mental retardation); inability to give consent; language barrier.
* Anticipated difficult airway (Mallampati class III and IV, thyromental distance \< 6 cm, mouth opening \< 3 cm, neck extension \<80° and neck flexion \<35°, inability to prognath, meaning bringing lower mandibular before the upper maxilla)
* Patient with history of neck rigidity or instability
* BMI \> 30
* Patient with beard (because of recognized risk for difficult ventilation)
* Patient with history of oropharyngeal or tracheal surgery (excluding adenoidectomy, amygdalectomy and teeth removal)
* Severe coronary artery disease
* Serious cardiac arrhythmias (including atrial fibrillation)
* Use of β-blockers (all types)
* History of opioid or illicit drug substance abuse
* Chronic use of psychotropic and/or opioid drugs
* Allergy to remifentanil or propofol
* Pregnancy
* Contraindications to mask ventilation (GI tract obstruction, pregnancy, active GERD, non-fasting patients)
* Difficult mask ventilation (before randomization at the first laryngoscopy)

Exclusion Criteria:

* Unexpected difficult airway requesting excessive, possibly painful airway manipulations
* Requiring hemodynamic support with vasopressors or inotropes 5 minutes before first laryngoscopy to 3 minutes after insertion of ETT
C: Inclusion Criteria:

* Elective surgery requiring oral endotracheal intubation for general anesthesia;
* Anticipated extubation in the operating room;
* American Society of Anesthesiologists (ASA) physical status 1-3;
* Age between 18 and 99 years;
* Body Mass index ≥ 40 kg/m2.

Exclusion Criteria:

* Refusal of participation by attending anesthesiologist;
* Indicated rapid sequence induction for any reason including, but not limited to high risk of aspiration
* Indicated fiberoptic awake intubation.
D: Inclusion Criteria:

The patients who will undergo general anesthesia for abdominal surgery, American Society of Anesthesiologists physical status I to III, The patients who were aged between 20 and 75

Exclusion Criteria:

Our exclusion criteria were to have a history of emergency intubation or a difficult intubation, to have a body mass index higher than 35 or a rheumatologic disease that cause limitation of cervical motion, to have a previous history of cervical operation or tumor, trauma or infection on upper airway, and to have no tooth.

Answer: C