Incidence of Acute Laryngeal Injury Following Endotracheal Intubation

In the United States, 55 000 patients receive care in more than 6 000 intensive care units
(ICUs) each day. The most common reason for ICU admission is respiratory failure and the need
for a mechanical ventilator. Although 50% to 70% of patients survive their acute illness, the
remainder are left with massive impairments in health and overall functioning. One of the
most severe post-ICU complications is airway scaring directly resulting from endotracheal
intubation.

Scarring of the vocal cords or trachea after intubation results from mucosal injury by an
endotracheal tube (i.e. breathing tube). The initial mucosal injury ultimately heals with
pathologic fibrotic contracture. This fibrosis physiologically restricts ventilation, and
produces life-threatening dyspnea and airway obstruction. Acute and chronic airway injury
following intubation is largely unappreciated owing to the fact that the long-term sequelae
of intensive respiratory support is rarely managed by practitioners providing acute care.
Treatments for chronic airway injury are suboptimal. They are largely surgical and offer
marginal improvement in breathing while causing permanently worsened voice. Preventative
efforts to preserve laryngeal and tracheal function (through identification of modifiable
risk factors) could reduce the incidence of this devastating complication of medical care.
Additionally, early identification of acute laryngeal injury after intubation may prevent the
development of chronic complications. Patients with acute post-intubation airway injury
treated with early endoscopic surgery require significantly fewer procedures, and may avoid
an invasive open surgical reconstruction compared with patients treated with chronic fibrotic
scars.

The development of airway fibrosis and ventilatory obstruction has been linked to
inflammatory processes. Macrolide antibiotics such as azithromycin has been shown to reduce
mucosal airway inflammation. IN addition the combination of a macrolide antibiotic and
budesonide an inhaled corticosteroid has been shown to work synergistically to reduce
inflammation and modify the disease process of tracheal stenosis in rabbit models.

The purpose of this investigation is to delineate the incidence of acute and chronic
laryngeal injury following intubation within our health system. In addition, this study seeks
to identify risk factors for airway injury that may provide information to help reduce the
incidence of injury or increase the speed of diagnosis through hospital based process
measures. Finally, in patients with acute laryngeal injury, this study seeks to investigate
the effects of azithromycin and budesonide to improve objective and subjective breathing
measures in patients with Acute Laryngeal injury (ALgI) following endotracheal intubation.

Overview: Patients will be recruited from adult patients in the surgical and medical
intensive care units of Vanderbilt Medical Center who were intubated for greater than 48
hours. Following informed consent and study enrolment, data will be stored in a secure REDCap
database housed within a server located behind the Vanderbilt University Medical Center
(VUMC) firewall. Data analysis will be performed by KSP at VUMC.

Protocol: Within 72 hours of extubation, ICU patients will be approached for participation by
study KSP (they will be clinically evaluated for the ability to provide informed consent). If
they are not able to consent for themselves an LAR will be approached for consent by study
KSP. Consent will be electronic, paper, or via phone.

Consented and enrolled patients will undergo routine medical examination of their larynx with
flexible nasolaryngoscopy after anesthetizing and decongesting the nose with 1% lidocaine
mixed in oxymetazoline. During the examination, patients will be asked to sniff (which
triggers opening of the vocal cords), and say "Eee" which (triggers closing). These maneuvers
allow assessment of vocal fold movement. The evaluation will be recorded for subsequent
blinded review. Recordings will be coded with a research identifier and stored digitally
securely on a harddisk locked within the principle investigators office. If acute laryngeal
injury is noted on examination, a repeat office-based examination of the larynx will be
scheduled in 8 to 12 weeks.

The second phase of this study will investigate the effects of azithromycin and budesonide to
improve objective and subjective breathing measures in patients with Acute Laryngeal injury
(ALgI) following endotracheal intubation. The consenting process for these patients will
mirror the first phase. In patients with ALgI, patients will be randomized to a medical
therapy group consisting azithromycin 250mg or budesonide of 0.5mg for 14 days or non-drug
placebo group. This study will be double blinded. For participants, a repeat examination will
be scheduled at 12 weeks and at that time patients will be asked to complete surveys (CCQ,
VHI-10, SF-12).

Consented patients will also have information abstracted from their medical record. Pertinent
information collected will include patient-specific covariates; i.e. medical co-morbidities,
laboratory values, and demographics as well as procedure-specific covariates; i.e.
endotracheal tube size, length of intubation, recorded endotracheal tube cuff pressures, and
the number of recorded intubation attempts. The initial and follow up examinations will be
non-billable and provided no-cost to the patients. If chronic laryngeal injury is noted on
follow-up examination, the patients will then be referred within the institution as a routine
patient and offered standard treatment options as directed by a fellowship trained
laryngologist.

Inclusion Criteria:

1. English-speaking

2. Greater than 24 hours and less than 7 days of intubation in the intensive care unit

Exclusion Criteria:

1. Age under 18 years on admission

2. Patients with anticipated discharge 5 days after extubation

3. Patients who are dependent for activities of daily living (ADLs) in the 30 days prior
to admission

4. Patients unable to consent

5. Patients with neck trauma

6. Patients with head and neck malignancies

7. Patients with pre-existing laryngeal or tracheal stenosis

8. Patients with other pre-existing respiratory conditions such as chronic obstructive
pulmonary disease (COPD), asthma, neuromuscular dystrophies, cystic fibrosis,
bronchiectasis

9. Patients who had been previously intubated for an extended period of time

10. Patients who are pregnant or currently breastfeeding

11. Patients with allergies to study medications

12. Patients with a resting heart rate greater than 100 beats per minute

13. Patients with a prolonged corrected QT (QTc) interval (>450 msec) or the use of
medications that prolong the QTc interval or are associated with Torsades de pointes
(with the exception of amiodarone)24

14. Patients with severe hearing impairment documented by audiometric testing