If intubation continues to be performed by paramedics, a smarter approach must be taken. Professional associations must advocate for more live clinical experience during school. EMS systems must monitor intubation performance and ensure each paramedic’s proficiency. Equipment must be available to help intubation and monitor tube placement after. Individual paramedics must recognize when intubation is appropriate, when it is not and when to stop an intubation attempt.
ETI should be considered one option for airway management that may not be best for some patients. For cardiac arrest, chest compressions and defibrillation should never be compromised to place any airway device. For patients with a pulse, other airway management options and transport time must be considered to determine if intubation should be done in the field.
Once the decision to proceed with intubation is made, steps should be taken to maximize the chance of first-pass success. The following steps provide a methodical approach to manage the airway of any intubation candidate. It emphasizes preparation, use of techniques that help intubation and when to use a supraglottic airway device instead. The problems that intubation is intended to help should never be made worse during the procedure. Remember, no intubation is always better than bad intubation, even if an ET tube is eventually placed.
Professional athletes would never swing a baseball bat or golf club in a game or tournament without taking practice swings first. Paramedics are called upon to perform complex skills in adverse conditions—skills they may only practice a few times each year. This is why paramedics must practice airway management as often as possible before the next call.
Intubation involves much more than passing an ET tube through vocal cords. Packages must be opened, equipment must be prepared, fine motor control is needed and critical thinking is required at each step. Repeatedly practicing each step will make them easier to complete during an emergency. Go through an entire airway management scenario, including intubation failure, with a mannequin at the beginning of each shift.
2. Determine if intubation is indicated
The use of basic adjuncts to manage a patient’s airway or placing a supraglottic device may be better than an ET tube for some patients. Some excellent EMS systems have high cardiac arrest resuscitation rates with supraglottic airway devices. Before intubating a patient in cardiac arrest, ask if it is possible to do so without interrupting chest compressions. For patients with a pulse, ask if adequate ventilation and airway protection can be achieved with a less invasive method until you get to the hospital. A successfully managed airway does not have to be intubated.
3. Prepare the patient
Since paramedics only intubate in emergencies, there is often a sense of urgency and need to rush through the procedure. Lack of preparation often leads to failure. Basic steps taken with each patient before the intubation attempt will increase the chance of first-pass success.
Start with the basic airway adjuncts. Insert a nasal airway and oral airway if the patient will tolerate it. Preoxygenate the patient before an intubation attempt to increase their reserve capacity, but never hyperventilate a patient to do this. Hyperventilation is harmful for a number of reasons.
Suction every patient’s mouth with a rigid suction catheter. It will much be easier to visualize the airway landmarks if secretions are suctioned before the laryngoscope is introduced. This can be done during chest compressions, between ventilation with the BVM or with an oxygen mask in place.
To align the airway landmarks for better visualization, position the patient’s head so the ears are level with their sternum. This is best done by placing blankets, towels or pillows under their head and shoulders.
4. Prepare your equipment
Assemble all of your equipment, including backup devices, before attempting intubation. Start by attaching the capnography circuit to the BVM. Assemble the ET tube with a stylette and syringe and check the light source on the laryngoscope. Have the bougie and supraglottic device out as well. All equipment that might be needed should be within reach and not have to be located in a bag after the attempt begins.
5. Advance the laryngoscope blade
With the patient’s head in position, their mouth suctioned and your equipment ready, introduce the laryngoscope blade. Imagine asking the patient to open their mouth wide. Advance the blade down the tongue and identify the epiglottis.
If using a curved blade, insert the tip into the vallecula, which is just above the epiglottis. With a straight blade, advance the tip just past the epiglottis. Gently lift the blade forward and aim for the patient’s left foot.
For novice intubators, there’s a tendency to panic if the vocal cords are not immediately visualized after the laryngoscope is introduced. Identifying the epiglottis first and recognizing other airway landmarks will prevent this. Think of it as a “You Are Here” mark on a map and the trachea is above and behind it. If the trachea can not be visualized after it is moved, proceed with the following steps.
Applying Backward, Upward, Rightward Pressure to the lower third of the thyroid cartilage may help bring the airway landmarks into view. While your left hand holds the laryngoscope, place the middle finger of your right hand just below the thyroid cartilage. Gently pull it toward the patient’s right ear.
Do not lose sight of the landmarks once they are found. Either have an assistant hold them in that position, or gently let go of the cartilage with your right hand while you manipulate the laryngoscope to keep them in view. Your right hand is now free to pass the tube.
The BURP maneuver is different from cricoid pressure. Pressing the cricoid cartilage downward is believed to close off the esophagus and help prevent aspiration. Its effectiveness has been questioned and it can impair the view of upper airway structures during intubation. Pressure is applied to the thyroid cartilage during the BURP maneuver, and is designed only to assist in viewing airway landmarks. If cricoid pressure is applied during ventilation with a BVM and landmark visualization is limited during intubation, consider releasing it and try the BURP maneuver.10
If you have sight of the epiglottis but a limited view of other airway landmarks, consider the bougie next. Also known as a flex-guide ET tube introducer, this is a curved tip stylette which is easier to place than a larger diameter ET tube. Place the upward tip behind the epiglottis and advance it.
When placed in the trachea, vibrations are usually felt as the tip passes against the tracheal rings. Resistance should also be met after it is advanced approximately 20 cm when the trachea narrows. This is marked with a black line. Slide the ET tube over the bougie, and rotate the tube if resistance is met. Assume the bougie is in the esophagus if no resistance is felt.
8. Abandon the attempt and reassess
An intubation attempt should be stopped if:
- Compressions must be interrupted on a patient in cardiac arrest
- A patient with a pulse desaturates or becomes bradycardic
- Airway landmarks are not located after the previous steps.
Resume basic airway management and assess why the attempt was unsuccessful. Then think about what would be different with a second intubation attempt. Success is unlikely if the same paramedic uses the same laryngoscope blade under the same conditions as the first attempt. At this point the smartest step is usually to place a supraglottic device.
9. Confirm placement
During episodes of “COPS,” viewers frequently see people get arrested after breaking the law. Although millions of viewers watch a suspect break the law, a narrator reminds viewers all suspects are innocent until proven guilty in a court of law. The same concept applies to confirming placement of an airway device. Even if the tube was visualized passing the landmarks, it must be proven by the following methods.
The most reliable method to confirm tube placement is waveform capnography. Each breath produces a waveform and a numeric value of the amount of carbon dioxide exhaled with each breath (called end-tidal CO2, or ETCO2). Continuous monitoring provides immediate feedback if the device becomes misplaced. A normal ETCO2 level is 35-45 mmHG. Expect it to be lower in patients in shock or cardiac arrest and higher in patients with respiratory failure. Having the circuit attached to the BVM prior to intubation will provide a baseline for what the post-intubation ETCO2 level should be.
Listen to the patient’s epigastrium with a stethoscope and look at the monitor during the first ventilation through the tube. A waveform should appear on the monitor and only faint sounds should be heard over the epigastrium. Gurgling sounds with a very small or absent waveform indicate the tube is misplaced. Remove it before another ventilation is delivered and resume basic management.
Listen to both sides of the patient’s chest next. Breath sounds should be equal on both sides. Breath sounds on the right side but not the left indicate the tube is too deep. Pull it back slowly until breath sounds are equal.
10. Secure the tube
Once tube placement is confirmed it must be secured with a commercial device or tape. Never rush this step and pay close attention to details. If vomit or blood are near the patient’s mouth, wipe it off before the tube is secured. A cervical collar can help keep the tube in place by limiting head movement during patient movement.
Like many things in EMS, the choice of device is less important than how it’s used. While securing the tube, imagine a worst-case scenario. Would it still be in place if the patient was accidentally dropped down stairs?
It is also important to be prepared if the tube becomes displaced. An assembled BVM should stay with any intubated patient.
A Note on Ventilation
Another problem associated with intubation is hyperventilation after the tube is placed. This causes a decrease in cardiac output and cerebral perfusion. Mechanical ventilation is complicated and beyond the scope of this article, but as a rule the ventilation rate and tidal volume should be titrated to maintain an ETCO2 reading of 35-45 mmHg and pulse-ox reading above 95%.