Fiberoptic Intubation - An Insight

Introduction:

Since the inception of the flexible fiberoptic bronchoscope, a variety of new airway tools have emerged, necessitating clinicians' comprehension of their functions and limitations to ensure appropriate selection. With numerous contemporary airway adjuncts available, our objective was to delineate the significance of flexible fibreoptic intubation in decision-making and the handling of both expected and unexpected difficult airways. They also conducted a review of recent literature on the application of flexible fibreoptic intubation in specific patient demographics prone to difficult intubation, affirming its continued importance in difficult airway management.

What Is Fiber Optic Technology?

Thin, flexible glass fibers with a diameter of 8 to 25 micrometers that can transfer light throughout their length are the basis of fiber optic technology. Through internal reflection, light can pass through these fibers because they are isolated by a layer of glass with varying optical densities. Images are sent through the scope by a coherent bundle of fibers that maintains exact orientation at both ends. A focused image is produced via lenses at the scope's tip and eyepiece, and illumination is further provided by a separate fiberoptic bundle that is connected to a light source. An eyepiece mounted atop a control handle featuring a focusing ring is usually attached to a thin, flexible fiberscope to form the fiberoptic bronchoscope. The distal tip of the scope can be flexed or extended using a thumb control lever. Different processes are facilitated by a distinct port along the scope. A separate port along the scope facilitates various procedures such as suction, saline injection, or diagnostic tool passage.

The integration of a charge-coupled device (CCD) camera, which sends digital images to an external monitor, is a more recent development. With hybrid technology, bronchoscope diameters can be reduced, working channels can be expanded, and flexibility is increased by combining fiberoptic bundles with a CCD camera at the handle. Although stiff or semirigid fiberscopes, such as the Bonfils and UpsherScope, have also demonstrated efficacy in managing problematic airways, they are not the subject of this review. The components of flexible fiberoptic bronchoscopes have been the subject of much discussion.

What Is the Patients Preparation for Fiberoptic Intubation?

• Informed Consent: Obtain the patient's informed permission by explaining the procedure to them and outlining its goals, advantages, and any hazards.

• Preoperative Evaluation: Conduct a comprehensive preoperative evaluation of the patient's medical history, allergies, prescriptions, airway, and past anesthetic experiences.

• NPO Status: To lower the risk of aspiration, make sure the patient has been NPO (nothing by mouth) for the necessary amount of time before the treatment.

• Preoperative Drugs: Give the patient any preoperative drugs that the anesthesiologist prescribes, such as sedatives or anxiolytics, to help them unwind and cooperate during the procedure.

• Positioning: To maximize airway alignment and visualization during fiberoptic intubation, position the patient appropriately. This is often in a semi-Fowler's posture with the head slightly elevated.

• Monitoring: Use common monitoring tools, such as a blood pressure cuff, pulse oximeter, and electrocardiogram (ECG), to keep an eye on the patient's vital signs while it goes through the process.

• Topical Anesthesia: To reduce discomfort during fiberoptic intubation, topical anesthesia is applied to the patient's nasal passages and oropharynx.

• Preoxygenation: To boost the oxygen reserve and reduce the chance of hypoxemia (low oxygen levels) during the procedure, oxygenate the patient with 100 percent oxygen using a facemask or nasal cannula.

• Assistance: Make sure the right people are there to help with the process and handle any potential difficulties, such as anesthesiologists, anesthesia assistants, and nursing staff.

• Equipment Check: Before beginning the process, make sure the fiberoptic bronchoscope and any accompanying equipment are operational and well assembled.

• Documentation: Keep a record of the patient's initial vital signs, the results of any airway assessment, any prescribed preoperative drugs, and any other pertinent data in the patient's medical file.

What Is the Procedure of Fiberoptic Intubation?

• Preparation: Assemble the patient and ensure all necessary monitors, such as blood pressure, pulse oximetry, and ECG, are connected. The fiberoptic bronchoscope, endotracheal tube, lubricating jelly, topical anesthetic, and suction should all be ready.

• Placing the Patient: To maximize airway alignment, place the patient appropriately, usually in a sniffing position.

• Topical Anesthesia: To lessen discomfort and the gag reflex, apply topical anesthetic to the patient's mouth cavity or nasal passages.

• The Bronchoscope Fiberoptic Insertion: Depending on the patient's anatomy and the clinician's preference, insert the fiberoptic bronchoscope into the mouth cavity or nasal channel.

• Visualization of the Airway: Move the fiberoptic bronchoscope gently and cautiously while they observe the trachea, bronchi, and voice cords, among other airway structures.

• Advancing the Endotracheal Tube: The endotracheal tube is advanced by passing it over the fiberoptic bronchoscope, passing it over the vocal cords, and guiding it into the trachea once the vocal cords have been visualized.

• Confirmation of Tube Placement: Verify that the endotracheal tube is positioned correctly by checking the CO2 waveform capnography, auscultating both sides of the chest, and monitoring the rise and fall of the chest.

• Securing the Endotracheal Tube: After the placement has been verified, use the proper techniques to secure the endotracheal tube in place, such as tying it to the patient's face or using adhesive tape.

• Post-Intubation Care: After intubation, the patient's vital signs, oxygen saturation, and airway condition should be continuously monitored. Secure the tube and make sure the patient's medical record has documentation of the procedure and tube placement.

• Management of Complications: Be ready to handle possible side effects before and after the surgery, such as bleeding, hypoxia, and laryngospasm.

What Are the Indications and Contraindications of Fiberoptic Intubation?

Indications

• A history of awake fiberoptic intubation or known problematic intubation.

• Expected challenging intubation.

• Following unsuccessful intubation in an unexpectedly challenging airway.

• Known or believed to be problematic mask ventilation.

• C-spine instability.

• Abnormal anatomy, such as head and neck malignancies and congenital airway abnormalities.

• Upper airway, face, and neck trauma.

Contraindications:

Complete Contraindications:

• Refusal of the patient or lack of cooperation.

Associated Contraindications:

• Absence of personnel with training.

• The danger of an imminent blockage in the airway.

• Coagulopathy (blood clotting is impaired), or airway hemorrhage.

• Sensitivity to a local anesthetic.

• The base of fracture (for nasal passage) in the skull.

What are the Complications of Fiberoptic Intubation?

• Oversedation.

• Apnea.

• Trauma.

• Bleeding.

• Laryngospasm (difficult to breathe or speak for a short duration due to vocal cord spasm).

• Vomiting.

• Respiratory depression.

• Airway obstruction.

• Local anesthetic allergy.

• Toxicity.

• Risk of aspiration due to loss of laryngeal reflexes.

Conclusion:

Flexible FOI is becoming less common as a result of the introduction of new airway instruments such as indirect laryngoscopes. Still, it is essential to managing difficult airways because it gives the anesthetist a safe management plan for expected difficult airways and a rescue plan for unexpected difficult airways. When it comes to utilizing FOI, anesthetists ought to have a low bar, and if they do decide to do so, they need to give careful thought to doing so on an awake patient. For many patients, especially those with challenging laryngoscopy (direct and indirect) and cervical spine injuries, awake FOI is still a vital option for managing their airway.