Endotracheal intubation pt.2 Flashcards
What can the equipment needed for endotracheal intubation be divided into?
Preparation
Pre-oxygenation
Direct laryngoscopy
Video laryngoscopy
Back up
Equipment needed for preparation
- Intravenous access
- Hemodynamic monitoring
- Stethoscope
- Pulse oximeter
- End-tidal carbon dioxide (EtCO2) monitor
- Suction catheter attached to continuous suction
- Cardiac arrest cart with resuscitation medications
- Rapid sequence intubation medications (paralytic, sedative, and/or dissociative agent)
- Defibrillator
Equipment needed for pre-oxygenation
- Nasal cannula or high-flow nasal cannula (HFNC)
- Bag-valve mask with masks of various sizes
- Positive end-expiratory pressure (PEEP) valve
- Oral and nasal airways of various sizes
- Non-rebreather mask
- Supplemental oxygen
Equipment needed for direct laryngoscopy
- Laryngoscope handle with batteries
- Laryngoscope blades of various sizes and shapes
- Endotracheal tubes of various sizes+
- Malleable stylet+
- 10cc syringe+
- Tape+
Equipment needed for video laryngoscopy
Video laryngoscope connected to a power source
Rigid or malleable stylet (dependent on the brand of video laryngoscope)
Equipment needed for back up
Laryngeal mask airway (LMA)
Bougie
Cricothyrotomy tray
Magill forceps
Positioning of personnel during intubation
- The physician or another designated operator stands at the head of the bed
- The nurse in charge of medication administration should be to the patient’s left or in proximity to the site of medication administration.
- The respiratory assistant is in charge of ventilating the patient, manipulating the airway if required, and handing the endotracheal tube to the operator. They should stand to the right of the patient
- If in-line stabilization of the cervical spine is indicated, an additional assistant should be positioned to the left of the operator, ready to hold the neck in position.
Which may patients are more likely to cause more difficulties when intubating?
Patients with restricted cervical motion, obesity, and facial or neck trauma may present as difficult airways, and providers should anticipate alternative modes of intubation in these situations
- “Mallampati” class greater than or equal to 3 is predictive of difficult intubation. “Obstruction” or obesity may restrict visualization of the vocal cords. “Neck” mobility and any restriction of it can contribute to difficulty passing the endotracheal tube
What is the first step of endotracheal intubation?
- Time permitting, the first step in preparation is to perform an airway evaluation, which includes a history of intubation and difficult intubations.
- Evaluation of the external anatomy may be predictive of a difficult airway.
Mnemonic used to evaluate airway?
- “LEMON.” “Look” externally for signs of trauma, facial hair, neck masses, large tongue, or dentures
- “Evaluate” the 3-3-2 rule. Less than three fingers between the incisors, three fingers between the hyoid bone and the mental protuberance, and two fingers between the hyoid bone and the thyroid cartilage (Adam’s Apple) may be representative of a difficult airway
- M⫽Mallampati, O⫽Obstruction, N⫽Neck Mobility
What is the Mallampati score?
The Mallampati score is one assessment to describe the relative size of the base of the tongue compared to the oropharyngeal opening in hopes of predicting the difficult airway
When is the Mallampati score indicated?
The Mallampati score should be used in circumstances when a patient requires any type of anesthesia or is to be intubated. This will enable the proceduralist to prepare for airway anatomy challenges in advance of securing the airway
Percentage of patients with difficulties in masking, ventilate, or intubate
While the overall majority of patients are relatively easy to mask, ventilate and intubate, about 1 to 5% of patients are difficult to mask, ventilate, and 5% of patients are difficult to intubate
Mallampati scoring system
- The patient is seated and is asked to maximally extend/protrude their tongue without phonation
- The modified Mallampati score used routinely today is as follows:
Class 0: Any part of the epiglottis is visible
Class I: soft palate, uvula, and pillars are visible
Class II: soft palate and uvula are visible
Class III: only the soft palate and base of the uvula are visible
Class IV: only the hard palate is visible
Positioning when intubating
- Once the external evaluation of the patient is complete, the head position should be optimized to get the best possible view of the vocal cords
- The “sniffing position” has traditionally been considered the optimal position for direct laryngoscopy as it aligns the oral, pharyngeal, and laryngeal axes
- This position is achieved by elevating the patient’s head with a pillow or blanket, extending the head at the neck, and aligning the ears horizontally with the sternal notch.
- In morbidly obese patients, shoulder rolls may be utilized to elevate the head until the external auditory meatus aligns with the sternal notch
Preferred method of pre-oxygenation
- The preferred source of pre-oxygenation is a non-rebreather mask with 1-way valves that allow for delivery of close to 90% FiO2 and do not allow exhaled air to be re-inspired
- In apneic patients or patients with inadequate respiratory drive, bag-valve-mask ventilation with the highest possible level of FiO2 is the most appropriate method of pre-oxygenation
- Other oxygen masks without 1-way valves can provide up to 70% FiO2 with a tight seal around the patient’s face, and bag valve masks can often deliver a higher than ambient air FiO2
- Positive end-expiratory pressure (PEEP) using continuous positive airway pressure (CPAP) or non-invasive bilevel positive airway pressure (BiPAP) may be used in patients with pulmonary shunt pathologies as methods of pre-oxygenation
- Patients with underlying conditions causing alveoli to be perfused but not ventilated may benefit from increased PEEP using these mechanisms.
