Please select the eligibility criteria that correspond to the clinical trial below.
Title: Randomised Controlled Trial of Intubation With the McGrath Series 5 Video Laryngoscope vs the Macintosh Laryngoscope
Brief Summary: The simplicity of use and intuitive function of the McGrath video-laryngoscope suggests it may have a bigger role than as a back-up to conventional direct laryngoscopy and could possibly be the first-line laryngoscope for situations where difficult intubations are more likely or more hazardous. The incidence of difficult or failed intubation for an individual anaesthetist is related to their experience, decreasing as experience increases. The purpose of this trial is to evaluate the McGrath laryngoscope when used by relatively inexperienced anaesthetists, who are those most likely to encounter difficulties.

The null hypotheses to be tested is that there is no difference between the Macintosh and McGrath laryngoscope in terms of ease and success in intubation.


Options:
A: Inclusion Criteria:

* Adults (18 years and over) scheduled for elective surgery whose anaesthetic plan would normally include oral intubation using a Macintosh laryngoscope blade after induction of general anaesthesia and who have given valid informed consent.

Exclusion Criteria:

* Patients requiring special techniques for intubation such as rapid sequence induction
* Adults who have learning difficulties
* Are unconscious or very severely ill
* Have a terminal illness; are in an emergency situation
* Have a mental illness
* Have dementia
* Prisoners
* Those who could be considered to have a particularly dependent relationship with the investigator and other vulnerable groups.
B: Inclusion Criteria:

* Any patient over the age of 16 years, requiring urgent (within 30 minutes) endotracheal intubation, who are attended to by the critical care team will be eligible for enrolment

Exclusion Criteria:

* Patients who require intubation within 5 minutes or have contraindications to either of the study intubation technique will be ineligible
* cardiac arrest
* cardiopulmonary instability (oxygen saturation \<90% or systolic blood pressure \< 80 mmHg despite oxygen or fluid therapy)
* any clinical deterioration while awaiting randomization
* known prior or anticipated difficult intubation
* need for awake intubation (defined by sedation, topicalization and avoidance of neuromuscular blockade)
* pregnancy
* cervical spine precautions
* any patient deemed inappropriate for enrolment by the attending physician
C: 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.
D: Inclusion Criteria:

* Any patient who is ≥ 18 yrs. coming for elective surgery.
* Endotracheal tube is indicated for the procedure in the opinion of the attending anesthesiologist.
* Any operator who has performed ≥ 10 GlideScope intubations.

Exclusion Criteria:

* Any patient in whom the use of the GlideScope is contraindicated in the opinion of the attending anesthesiologist.
* Any patient with cervical spine abnormalities.
* Any patients with known or probable difficult airways (this rare occurrence is unlikely to be evenly distributed between the groups and could skew the data).
* Any patient requiring rapid sequence induction.

Answer: A