Indications for Intubation
Provided no contraindications, a short trial of non-invasive ventilation is justified in patients with acute hypercapnic respiratory failure due to acute exacerbation of COPD and in patients with acute cardiogenic pulmonary edema. Failure of non-invasive ventilation, determined clinically, is a common indication for escalation to mechanical ventilation.
|
Indication |
Definition |
Common Etiologies |
Special Considerations |
|---|---|---|---|
|
Hypoxemic Respiratory Failure |
Refractory hypoxemia PaO2 <55 with failure of non-invasive modes of oxygen delivery |
PNA, hemorrhage, pulmonary edema, ARDS |
|
|
Hypercapnic (Hypercarbic) Respiratory Failure |
Hypercapnia (PaCO2 >45) with acidemia (pH <7.35) |
COPD, asthma, obesity hypoventilation syndrome |
Patients with chronic hypercapnia often have compensated respiratory acidosis with PaCO2 >45 but without acidemia. Consider NIPPV (Bilevel) for ventilatory support for hypercapnia |
|
Airway Protection |
Clinical definition: in cases of low GCS (<8), apnea, or inability to clear secretions |
Intoxication, general anesthesia, head injury, encephalopathy, aspiration, UGIB, copious secretions not being cleared |
Consider naloxone prior to intubation if signs of opiate overdose |
|
Upper Airway Obstruction |
Tumor, tracheal stenosis, angioedema |
Consider oral/nasal airway for reversible obstruction. Consider back-up non-endotracheal modes of intubation by calling ENT and/or anesthesia |
|
|
Increased work of breathing
|
Often seen with severe metabolic acidosis requiring high minute ventilation which may exceed ability to compensate leading to tiring out and respiratory failure |
Any cause of severe metabolic acidosis (e.g., toxins, DKA), severe sepsis -> septic shock |
May consider intubating early when concerned for impending respiratory failure (patient can’t “keep up”) |
|
Neuromuscular weakness |
Reduced maximal inspiratory pressure (MIP) or FVC. Note: both are effort-dependent |
Neuromuscular diseases (e.g. ALS, GBS, myasthenia gravis), toxins (e.g. tetanus, tick bite) |
RT can measure and trend MIPs and FVCs at the bedside; absolute value and trajectory of trend are important when considering impending respiratory failure and proceeding with intubation |
There can be relative indications for intubation. These include: in the setting of hemodynamic instability or to safely perform a procedure or obtain an imaging study. The decision to intubate in these situations is considered based on risk/benefit discussion and patient-centered care.