Deciding When to Intubate a Patient

When should you intubate a patient?

Deciding when to intubate can be difficult. There are some instances when the indication for intubation is very clear, e.g. a comatose patient needs to be intubated immediately.

There are others in which intubation can be avoided. E.g. in patients who are alert and can protect their airway, such as patients with COPD or CHF (with pulmonary edema), Noninvasive positive pressure ventilation (NIPPV) may be used to avoid the need for intubation.

Patients who have at least one of the following 5 indications should be intubated.

1. Unable to maintain airway patency.
2. Unable to protect the airway against aspiration.
3. Failure to ventilate
4. Failure to oxygenate
5. Anticipation of a deteriorating course that will eventually lead to respiratory failure

5 questions that help you decide when to intubate a patient

Answering “yes” to any of the following 5 questions signifies the need to intubate the need to intubate the patient.

“A patient who can phonate clearly and answer questions appropriately demonstrates airway patency, adequate ventilation, vocal cord function, and cerebral perfusion with oxygenated blood. The level of alertness needed to maintain airway tone is the same required to maintain brisk protective reflexes to prevent aspiration of oral and gastric fluids. Aspiration of gastric contents can cause pneumonitis and result in prolonged mechanical ventilation ” UTD

The ability to phonate (produce speech sounds; vocalize.) and sense and swallow secretions is a more reliable sign of the patient’s capacity for airway protection than the gag reflex.
Patients who have secretions that are pooling, unable to swallow, should be intubated.

“Basic airway maneuvers, such as repositioning the patient’s head with a jaw-thrust or chin-lift, or placement of OPA and NPA can bypass flaccid, redundant upper airway tissue and provide an unobstructed passageway to the laryngeal inlet and trachea. In general, patients who require an OPA and tolerate its placement need intubation for airway protection.” UTD

Clinical Criteria for assessing oxygenation: “Clinically, hypoxic patients act restless and agitated, and with severe hypoxemia can appear cyanotic. As hypoxia worsens, confusion, somnolence, and obtundation occur. Patients are often tachycardic with mild to moderate degrees of hypoxia but exhibit profound bradycardia or agonal, non-perfusing rhythms with critically low oxygen saturations.”UTD

The gag reflex and the Decision to Intubate

Don’t use the gag reflex to determine when to intubate. It doesn’t reliably predict the need for intubation or the patient’s ability to protect their airway. “The gag mechanism does not contribute to laryngeal closure and airway protection, and a sizable segment of the normal adult population lacks a gag reflex.” Uptodate.com

* * Don’t wait too long to intubate. If you do that, you could miss the opportunity for a relatively safe intubation and wait to do it when the patient is crashing. E.g. Don’t delay intubation until the patient with anaphylaxis develops stridor or wait for worsening of hoarseness in the patient with smoke inhalation.

Factors to consider while deciding if to intubate difficult cases include “the patient’s respiratory status, the pathologic process, and the likelihood of deterioration, patient age and comorbidities, the need for transfer to another facility, and available resources.”

Don’t rely on the ABG in the emergent setting to determine the need for immediate intubation.

References

https://www.uptodate.com/contents/the-decision-to-intubate

http://emedicine.medscape.com/article/80222-overview