Endotracheal Tube-Associated Laryngeal Injury

Epidemiology

Prevalence

  • Laryngeal Injury is the Most Common Complication Associated with Endotracheal Tube Placement
    • Fiberoptic Study of Endotracheal Intubation-Associated Laryngeal Injuries (Intensive Care Med, 2010) [MEDLINE]: prospective study of n = 136 patients extubated after >24 hrs of mechanical ventilation (median duration of intubation = 3 days)
      • Approximately 73% of Patients Demonstrated a Laryngeal Injury
      • The Most Common Lesions were Edema (67% of Cases) and Abnormal Vocal Mobility (67% of Cases)
  • Laryngeal Injuries are More Common in Females than Males (Anesthesiology, 1992) [MEDLINE]
  • Obesity Does Not Appear to Increase the Risk of Laryngeal Injury, Although it Increases the Risk for Difficult Intubation (Intern Emerg Med, 2013) [MEDLINE]

Risk Factors for Endotracheal Tube-Associated Laryngeal Injury (Otolaryngol Head Neck Surg, 1994) [MEDLINE] and (Intensive Care Med, 2010) [MEDLINE]


Etiology


Clinical Manifestations/Treatment

Early Clinical Manifestations

Laryngeal Edema/Inflammation

  • Epidemiology
    • Laryngeal Edema/Inflammation is Observed Post-Extubation in >50% of Intubations (Chest, 1989) [MEDLINE] and (Intensive Care Med, 2010) [MEDLINE]: however, not all cases are significantly symptomatic
    • Clinically Significant Laryngeal Edema Occurs in 5-13% of Extubated Patients, But Only 1% Require Reintubation (Anesthesiology, 1992) [MEDLINE]
    • Study of Cuff Leak Volume and Risk of Post-Extubation Stridor (Chest, 1996) [MEDLINE]
      • Approximately 6% of Extubations Resulted in Post-Extubation Stridor
    • Study of Cuff Leak Testing in Predicting Post-Extubation Laryngeal Edema (Intensive Care Med, 2002) [MEDLINE]: n = 76
      • Approximately 11% of Patients Required Reintubation for Laryngeal Edema
    • Study of Post-Extubation Stridor and Value of Cuff Leak Test (Intensive Care Med, 2003) [MEDLINE]
      • Incidence of Post-Extubation Stridor was 12%
      • Risk Factors for Post-Extubation Stridor were Elevated APACHE II Score, Medical Reason for Admission, Difficult/Traumatic Intubation, History of Self Extubation, Overinflated Endotracheal Tube Cuff at ICU Admission, and Prolonged Intubation
    • Study of Endotracheal Tube Cuff Leak Test and Risk for Post-Extubation Stridor (Respir Care, 2005) [MEDLINE]
      • Female Patients, Patients with ETT Size/Laryngeal Diameter Ratio >45%, and Patients Intubated for >6 Days Were More Likely to Develop Post-Extubation Stridor
    • Study of Endotracheal Tube Cuff Leak Tests and Prediction of Post-Extubation Stridor (J Intensive Care Med, 2017) [MEDLINE]: n= 362
      • Post-Extubation Stridor Occurred in 9.4% of Unselected Critically Ill Patients
      • Patients with Post-Extubation Stridor More Frequently Required Reintubation (17.6%), as Compared to Patients without Post-Extubation Stridor (7.9%)
      • Patients with Post-Extubation Stridor Had a Longer Duration of Ventilation (3-13 Days), as Compared to Patients without Post-Extubation Stridor (2-9 Days)
      • Patients with Post-Extubation Stridor Had a Longer ICU Stay (6-17.5 Days), as Compared to Patients without Post-Extubation Stridor (4-13 Days)
      • Similar ICU Mortality was Observed in Both Groups (Patients with Post-Extubation Stridor vs Patients without Post-Extubation Stridor)
  • Risk Factors for Post-Extubation Laryngeal Edema
    • Age >80 y/o
    • Aspiration
    • Elevated Acute Physiology and Chronic Health Evaluation (APACHE) II Score
    • Excessive Endotracheal Tube Mobility (Due to Inadequate Securement)
    • Female Gender
    • Glasgow Coma Scale (GCS) <8
    • History of Asthma
    • Insufficient Sedation
    • Prolonged Intubation (Studies Define this Variably as ≥36 hrs to ≥3-6 Days)
    • Ratio of Endotracheal Tube Tube Diameter/Laryngeal Diameter >45%
    • Small Ratio of Patient Height/Endotracheal Tube Diameter
    • Traumatic Intubation
    • Use of Large Endotracheal Tube
      • Male: >8 mm
      • Female: >7 mm
    • Use of Orogastric/Nasogastric Tube (see Nasogastric Tube, Nasogastric Tube)
  • Physiology
    • Direct Pressure on Larynx and Surrounding Tissues (with//without Associated Inflammation)
  • Diagnosis
    • Endotracheal Tube Cuff Leak Test (see Endotracheal Tube Cuff Leak Test, Endotracheal Tube Cuff Leak Test)
      • Study of Cuff Leak Volume and Risk of Post-Extubation Stridor (Chest, 1996) [MEDLINE]
        • Cuff Leak Volume = Inspiratory Tidal Volume – Expiratory Tidal Volume with Endotracheal Tube Cuff Deflated
        • Cuff Leak Volume was Significantly Lower in Those Who Developed Post-Extubation Stridor (180 +/- 157 mL), as Compared to Those Who Did Not (360 mL +/- 157 mL)
        • Positive Predictive Value for Cuff Leak <110 mL was 80%
        • Sensitivity for the Absence of Post-Extubation Stridor with a Cuff Leak Volume >110 mL was 98% and the Specificity was 99%
      • Study of Cuff Leak Testing in Predicting Post-Extubation Laryngeal Edema (Intensive Care Med, 2002) [MEDLINE]: n = 76
        • Best Cutoff Value for Cuff Leak was 15.5% of Tidal Volume with Sensitivity of 75%, Specificity of 72.1%, Positive Predictive Value of 25%, Negative Predictive Value of 96.1%
      • Study of Post-Extubation Stridor and Value of Cuff Leak Test (Intensive Care Med, 2003) [MEDLINE]
        • Low Cuff Leak Volume (<130 mL or 12% of Tidal Volume) Can Identify Patients at Risk for Post-Extubation Stridor with Sensitivity of 85%/Specificity of 95%
      • Study of Endotracheal Tube Cuff Leak Test and Risk for Post-Extubation Stridor (Respir Care, 2005) [MEDLINE]
        • Female Patients, Patients with ETT Size/Laryngeal Diameter Ratio >45%, and Patients Intubated for >6 Days Were More Likely to Develop Post-Extubation Stridor
        • Failing the Cuff Leak Test was Not an Accurate Predictor for Post-Extubation Stridor
      • Systematic Review and Meta-Analysis of Cuff Leak Test (Intensive Care Med, 2009) [MEDLINE]
        • Cuff Leak Test Had Pooled Sensitivity of 63% and Pooled Specificity of 86%
        • Cuff Leak Test Had Positive Likelihood Ratio of 4.04 (95% CI: 2.21-7.40) and a Negative Likelihood Ratio of 0.46 (95% CI: 0.26-0.82)
      • Study of Endotracheal Tube Cuff Leak Test and Prediction of Post-Extubation Stridor (J Intensive Care Med, 2017) [MEDLINE]: n = 362
        • Endotracheal Tube Cuff Leak Testing (4 Different Tests) Demonstrated Sensitivity of 27-46%/Specificity of 70-88%, Positive Predictive Value of 14-19%, and Negative Predictive Value of 92-93% for Post-Extubation Stridor
        • Given High Rate of False Positives, Routine Leak Testing May Expose Patients to Undue Prolonged Mechanical Ventilation
      • American Thoracic Society/American College of Physicians Clinical Practice Guideline for Liberation from Mechanical Ventilation in Critically Ill Adults with Meta-Analysis of Cuff Leak Test (Am J Respir Crit Care Med, 2017) [MEDLINE]
        • Cuff Leak Testing Decreased the Rate of Reintubation (2.4% vs 4.2%) and Post-Extubation Stridor (4% vs 7%), But at the Expense of Delayed Extubation (9% Absolute Increase)
    • Cough Testing: can be used in addition to cuff leak testing
      • Absence of Both an Audible Cough and Cuff Leak Indicates that the Patient is 10x More Likely to Develop Post-Extubation Stridor (J Crit Care, 2004) [MEDLINE]
    • Laryngeal Ultrasound (see Laryngeal Ultrasound, Laryngeal Ultrasound): promising, but requires further study (J Crit Care, 2013) [MEDLINE]
  • Clinical
  • Treatment
    • Laryngeal Edema/Inflammation Generally Resolves within 24-48 hrs After Extubation
    • Careful Consideration of Extubation Technique, in Case Reintubation is Required
      • Extubation Over an Airway Exchange Catheter Can Be Considered in Selected Patients (Anesth Analg, 2007) [MEDLINE]
    • Racemic Epinephrine (see Epinephrine, Epinephrine)
    • HELIOX (see Heliox, Heliox)
    • Corticosteroids (see Corticosteroids, Corticosteroids)
      • Study of Intravenous Methylprednisolone to Prevent Post-Extubation Stridor (Crit Care Med, 2006) [MEDLINE]
        • Decreased Cuff Leak Volume was a Reliable Indicator to Identify Patients at High Risk for Post-Extubation Stridor
        • Cuff Leak Volume Increased After Methylprednisolone Doses (After a 2nd Injection in the One Dose Group and After the 2nd-4th Injection in the Four Dose Group), as Compared to Control
        • Single/Four Methylprednisolone Doses Effectively Decrease the Occurrence of Post-Extubation Stridor: however, there was no difference between the single and four methylprednisolone dose groups
      • Prospective Randomized Trial of Prophylactic Multiple Dose Dexamethasone to Decrease the Incidence of Post-Extubation Stridor in Adult Patients at High Risk for Laryngeal Edema (Crit Care, 2007) [MEDLINE]: n = 86
        • Prophylactic Dexamethasone (q6hrs x 4 Doses Throughout the Day Prior to Extubation) was Effective in Increasing the Cuff Leak Volume and Decreasing the Incidence of Post-Extubation Stridor (10% vs 27.5%) in Adult Patients at High Risk for Laryngeal Edema (Patients Intubated >48 hrs and with Cuff Leak Volume <110 mL): increase in cuff leak volume continued to occur 24 hrs after the last dexamethasone dose
        • No Significant Difference in Reintubation Rate Between the Two Groups (2.5% vs 5%)
      • French Randomized Trial of Methylprednisolone for the Prevention of Post-Extubation Laryngeal Edema (Lancet, 2007) [MEDLINE]: n = 761
        • In Patients Ventilated >36 hrs and Undergoing Planned Extubation, Methylprednisolone (20 mg Given 12 hrs and Then q4hrs Until Extubation) Decreased the Incidence of Post-Extubation Laryngeal Edema (3% vs 22%) and Need for Reintubation
      • Meta-Analysis of Prophylactic Intravenous Steroids to Prevent Post-Extubation Airway Complications in Adults (BMJ, 2008) [MEDLINE]
        • Prophylactic Intravenous Steroids Before Planned Extubation Decreased the Incidence of Laryngeal Edema and the Reintubation Rate (with Few Adverse Events)
      • Systematic Review of Corticosteroids to Prevent or Treat Post-Extubation Stridor (Cochrane Database Syst Rev, 2009) [MEDLINE]
        • Multiple Doses of Corticosteroids Begun 12-24 hrs Prior to Extubation Appears to Be Beneficial in Patients with a High Likelihood of Post-Extubation Stridor
      • Randomized Trial of Methylprednisolone to Prevent Post-Extubation Stridor and Reintubation (Minerva Anestesiol, 2011) [MEDLINE]: n = 71
        • In Patients with Cuff Leak Percentage <24% of Tidal Volume, a Single Methylprednisolone Dose 4 hrs Prior to Planned Extubation Decreased the Incidence of Post-Extubation Stridor and the Reintubation Rate
    • Reintubation: may be required

Vocal Cord Granuloma (see Vocal Cord Granulomas, Vocal Cord Granulomas)

  • Epidemiology
    • Vocal Cord Granuloma(s) May Occur in 30-40% of Patients Intubated for >3-4 Days (Intensive Care Med, 2010) [MEDLINE]
    • Duration of Intubation and Severity of Initial Laryngeal Injury Do Not Predict the Formation of Vocal Cord Granulomas (Am Rev Respir Dis, 1992) [MEDLINE]
  • Diagnosis
  • Physiology
    • Likely a Consequence of Prior Inflammation/Ulceration
  • Clinical
    • Hoarseness (see Hoarseness, Hoarseness): hoarseness persisting for >7-10 days after extubation is suggestive of the diagnosis
  • Treatment
    • Surgical Resection: often required (although some resolve spontaneously)

Vocal Cord Paralysis

Vocal Cord Ulceration

  • Epidemiology
    • Occurs in Approximately 33% of Cases
    • Most Commonly Occurs with Intubations Lasting >4 Days (Intensive Care Med, 2010) [MEDLINE]
  • Physiology
    • Direct Pressure on Larynx and Surrounding Tissues (with//without Associated Inflammation): usually occurs at the posteromedial aspect of the vocal cords
  • Diagnostic
  • Clinical
  • Treatment
    • Vocal Cord Ulcers Usually Resolve Spontaneously, But May Progress to Granulomas, Nodules, Interarytenoid Adhesions

Late Clinical Manifestations

Laryngotracheal Stenosis (see Tracheal Stenosis, Tracheal Stenosis)

  • Epidemiology
    • Occurs Weeks-Months After Intubation
    • Incidence: 1-21%
    • Risk Factors
      • Prolonged Intubation >7 Days: rarely occurs in those intubated for <3 days
  • Physiology
    • Laryngeal (Glottic) Stenosis: due to pressure from the endotracheal tube itself with local ischemia, inflammation, tissue necrosis, and scarring
      • Usual Location: posterior glottis and interarytenoid regions (where the endotracheal tube exerts the most pressure)
    • Tracheal Stenosis: due to high endotracheal tube cuff pressure (at 20 cm H20, cuff pressure will exceed the mean capillary pressure in the mucosa), with obstruction of capillary blood flow and associated ischemia, inflammation, erosion of them mucosa, tissue necrosis, distorted tracheal architecture, and scarring
      • Usual Location:
  • Diagnosis
  • Clinical
    • Failure to Wean from Mechanical Ventilation: in patients on mechanical ventilation
    • Subacute/Progressive Dyspnea (see Dyspnea, Dyspnea)
      • Usually Becomes Symptomatic Approximately 5 wks-Months After Extubation
  • Treatment
    • Rigid Bronchoscopy with Dilation/Laser Resection/Stenting: may be required for tracheal stenosis
    • Mitomycin C (see Mitomycin, Mitomycin): has been used to prevent tracheal restenosis after local procedures
    • Surgical Resection: may be required in refractory cases of tracheal stenosis

References

  • Laryngeal injuries secondary to nasogastric tubes. Ann Otol Rhinol Laryngol. 1981;90(5 Pt 1):469 [MEDLINE]
  • Laryngeal complications of prolonged intubation. Chest. 1989;96(4):877 [MEDLINE]
  • Evaluation of risk factors for laryngeal edema after tracheal extubation in adults and its prevention by dexamethasone. A placebo-controlled, double-blind, multicenter study. Anesthesiology. 1992;77(2):245 [MEDLINE]
  • Resolution of laryngeal injury following translaryngeal intubation. Am Rev Respir Dis. 1992;145(2 Pt 1):361 [MEDLINE]
  • Airway considerations in the management of patients requiring long-term endotracheal intubation. Anesth Analg. 1992;74(2):276 [MEDLINE]
  • Risk factors associated with prolonged intubation and laryngeal injury. Otolaryngol Head Neck Surg. 1994;111(4):453 [MEDLINE]
  • Association between reduced cuff leak volume and postextubation stridor. Chest. 1996;110(4):1035 [MEDLINE]
  • Gastroesophageal reflux in patients with subglottic stenosis. Arch Otolaryngol Head Neck Surg. 1998 May;124(5):551-5 [MEDLINE]
  • The cuff leak test to predict failure of tracheal extubation for laryngeal edema. Intensive Care Med. 2002;28(9):1267 [MEDLINE]
  • Post-extubation stridor in intensive care unit patients. Risk factors evaluation and importance of the cuff-leak test. Intensive Care Med. 2003;29(1):69 [MEDLINE]
  • How to identify patients with no risk for postextubation stridor? J Crit Care. 2004;19(1):23 [MEDLINE]
  • The endotracheal tube cuff-leak test as a predictor for postextubation stridor. Respir Care. 2005;50(12):1632 [MEDLINE]
  • Vocal fold injury following endotracheal intubation. J Laryngol Otol. 2005 Oct;119(10):825-7 [MEDLINE]
  • The endotracheal tube cuff-leak test as a predictor for postextubation stridor. Respir Care. 2005;50(12):1632 [MEDLINE]
  • Intravenous injection of methylprednisolone reduces the incidence of postextubation stridor in intensive care unit patients. Crit Care Med. 2006;34(5):1345 [MEDLINE]
  • Association of airway abnormalities and risk factors in 37 subglottic stenosis patients. Otolaryngol Head Neck Surg. 2006 Sep;135(3):434-7 [MEDLINE]
  • Intravenous injection of methylprednisolone reduces the incidence of postextubation stridor in intensive care unit patients. Crit Care Med. 2006;34(5):1345 [MEDLINE]
  • Laryngeal ultrasound: a useful method in predicting post-extubation stridor. A pilot study. Eur Respir J. 2006;27(2):384 [MEDLINE]
  • Dexamethasone to prevent postextubation airway obstruction in adults: a prospective, randomized, double-blind, placebo-controlled study. Crit Care. 2007;11(4):R72 [MEDLINE]
  • 12-h pretreatment with methylprednisolone versus placebo for prevention of postextubation laryngeal oedema: a randomised double-blind trial. Lancet. 2007;369(9567):1083 [MEDLINE]
  • Age and comorbidity as risk factors for vocal cord paralysis associated with tracheal intubation. Br J Anaesth. 2007 Apr;98(4):524-30. Epub 2007 Mar 6 [MEDLINE]
  • Short-term effects of endotracheal intubation on voice. J Voice. 2007 Nov;21(6):762-8. Epub 2006 Aug 14 [MEDLINE]
  • Continuous airway access for the difficult extubation: the efficacy of the airway exchange catheter. Anesth Analg. 2007;105(5):1357 [MEDLINE]
  • Risk factors evaluation and the cuff leak test as predictors for postextubation stridor. J Med Assoc Thai. 2008;91(5):648 [MEDLINE]
  • Prophylactic administration of parenteral steroids for preventing airway complications after extubation in adults: meta-analysis of randomised placebo controlled trials. BMJ. 2008;337:a1841. Epub 2008 Oct 20 [MEDLINE]
  • Cuff-leak test for the diagnosis of upper airway obstruction in adults: a systematic review and meta-analysis. Intensive Care Med. 2009;35(7):1171 [MEDLINE]
  • Spiral CT virtual bronchoscopy with multiplanar reformatting in the evaluation of post-intubation tracheal stenosis: comparison between endoscopic, radiological and surgical findings. Eur Arch Otorhinolaryngol. 2009;266(6):863 [MEDLINE]
  • Corticosteroids for the prevention and treatment of post-extubation stridor in neonates, children and adults. Cochrane Database Syst Rev. 2009 [MEDLINE]
  • Post-intubation laryngeal injuries and extubation failure: a fiberoptic endoscopic study. Intensive Care Med. 2010 Jun;36(6):991-8. Epub 2010 Mar 18 [MEDLINE]
  • Postextubation obstructive pseudomembranes: a case series and review of a rare complication after endotracheal intubation. Lung. 2011 Feb;189(1):81-6. Epub 2010 Nov 17 [MEDLINE]
  • Methylprednisolone reduces the rates of postextubation stridor and reintubation associated with attenuated cytokine responses in critically ill patients. Minerva Anestesiol. 2011 May;77(5):503-9 [MEDLINE]
  • Laryngeal injury from prolonged intubation: a prospective analysis of contributing factors. Laryngoscope. 2011;121(3):596. Epub 2010 Dec 16 [MEDLINE]
  • The effect of body mass index on intubation success rates and complications during emergency airway management. Intern Emerg Med. 2013 Feb;8(1):75-82. Epub 2012 Nov 25 [MEDLINE]
  • Predicting laryngeal edema in intubated patients by portable intensive care unit ultrasound. J Crit Care. 2013 Oct;28(5):675-80. Epub 2013 Jun 24 [MEDLINE]
  • Cuff Leak Test for the Diagnosis of Post-Extubation Stridor. J Intensive Care Med. 2017 Jan 1:885066617700095. doi: 10.1177/0885066617700095 [MEDLINE]
  • An Official American Thoracic Society/American College of Chest Physicians Clinical Practice Guideline: Liberation from Mechanical Ventilation in Critically Ill Adults. Rehabilitation Protocols, Ventilator Liberation Protocols, and Cuff Leak Tests. Am J Respir Crit Care Med. 2017;195(1):120 [MEDLINE]