Asleep Fiberoptic vs Direct Laryngoscopy Effect on Hemodynamic Stability Using Opioid Free Anesthesia Induction

Background: Intubation has always been linked to a transient increase in blood pressure and heart rate that could be deleterious in elderly and hemodynamically unstable patients. Fiberoptic intubation, which is currently used for suspected difficult intubation, could cause less marked rise in blood pressure and heart rate. Furthermore, "opioid free anesthesia" has gained popularity lately to avoid opioid adverse effects ranging from respiratory depression, postoperative ileus, sedation, nausea, vomiting and urinary retention.

Specific aims: The primary objective of this study is to compare blood pressure and heart rate between the fiberoptic and direct oral intubation using opioid free anesthesia induction. Secondary objectives include comparing the time needed for intubation and the incidence of postoperative sore throat, hoarseness, and upper airway trauma.

Methods: In this prospective randomized clinical trial, 90 (45 in each group) adults aging between 18 to 55 years, scheduled for elective surgery under general anesthesia, will be recruited over 1 year of work. Patients will be randomly allocated to 2 groups: The direct conventional laryngoscopy group performed with N3 (for females) or N4 (for males) Macintosh laryngoscope blade, and the fiberoptic guided intubation group.

Significance: Studies comparing hemodynamic stability using fiberoptic intubation versus direct oral intubation in opioid free anesthesia are limited. The present study will assess whether fiberoptic intubation causes less hemodynamic instability than direct oral intubation in opioid free anesthesia induction, which will benefit patients with normal airways.

Inclusion criteria

• ASA (American Society of Anesthesiologists) physical status I and II
• Range age of 18-55 years' old
• Scheduled for elective surgery under general anesthesia.

Exclusion criteria

• History of cardiovascular diseases.
• History of lung disease.
• Hypertensive patient (BP> 140/90)
• Patient taking medications that affect blood pressure and heart rate
• Morbid obesity (BMI >30)
• Severe GERD
• Predicted difficult airway (Short TMD <6 cm, Upper li bite test grade III, Mallampati score

>III)

• Neck instability
• Patient planned to receive rapid sequence intubation
• Patient refusal to participate
• History of difficult intubation/ ventilation