Tracheal Cuff Pressure and Postoperative Complications

Hospital de Clinicas de Porto Alegre362 enrolled

Overview

This prospective observational study aims to identify risk factors for tracheal mucosal injuries caused by orotracheal tube use during the intraoperative period in patients undergoing elective surgeries at the Hospital de Clínicas de Porto Alegre. The study will recruit patients sequentially for elective procedures requiring general anesthesia and orotracheal intubation. Primary outcomes include symptoms such as hoarseness, pharyngolaryngeal pain, cough, and hemoptysis, assessed up to 30 days post-surgery. A risk score for tracheal injuries will be derived.

Orotracheal tubes are widely used in medical practice to secure the airway and enable invasive mechanical ventilation. Modern tubes are made of medical-grade PVC with an inflatable cuff at the distal end to isolate the lower airway, prevent gas leaks from ventilation, and reduce contamination risks from upper airway secretions or gastric content. Although current cuffs are high-volume, low-pressure, overinflation complications are common, leading to variable severity lesions (isolated or confluent lesions, tracheal mucosal edema, erosions, or ulcerations with bleeding), and symptoms like dysphonia/aphonia (15-80%), cough, pain, and hemoptysis (10-15%). Overinflation can compromise tracheal mucosal perfusion, causing ischemia, necrosis, tracheoesophageal fistulas, or tracheal rupture, especially in patients requiring prolonged intubation. Even short exposures (hours) can cause significant lesions. Many physicians rely on manual palpation or experience to set cuff pressure, often inaccurately. This study will evaluate risk factors in elective surgical patients at HCPA, using multivariate regression to identify independent variables and derive a risk score.

Study Type

OBSERVATIONAL

Enrollment

362

Conditions

Tracheal Intubation Postoperative Complications (Cardiopulmonary)

Eligibility

Sex: ALLMin age: 18 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Age greater than 18 years. * Patients scheduled for elective procedures requiring general anesthesia and orotracheal intubation. Exclusion Criteria: * Age less than 18 years. * Refusal to participate in the study. * Surgeries performed on an urgent or emergency basis. * Surgeries in pregnant women. * Cardiac surgeries. * Surgeries requiring single-lung ventilation. * Head and neck surgeries. * Surgeries on the cervical segment of the dorsal spine. * Surgeries requiring lateral or prone positioning. * Anticipated difficult airway (unanticipated difficult airways will be included). * Insufficient fasting time. * Surgeries in patients admitted to intensive care units. * Patients presenting the same symptoms included in the outcomes to be measured (pre-existing hoarseness, pain, cough, hemoptysis). * Tracheostomized patients or those with previous tracheobronchial segment lesions.

Outcomes

Primary Outcomes

Presence of Tracheal Injury Symptoms (Composite Outcome).

Composite of hoarseness, pharyngolaryngeal pain, cough, and hemoptysis related to orotracheal tube use during surgery. Hoarseness, pain, and cough assessed via verbal numerical scale (0 = absent, 10 = worst possible). Hemoptysis assessed as present/absent, and volume (\>100 ml/24h considered massive).

Time frame: First 24 hours post-op to 30 days post-op

Secondary Outcomes

Independent Variables for Tracheal Complications.

Identification of independent variables (e.g., sex, age, tube duration, tube diameter, intubation attempts, unanticipated difficult airway, surgical table position, vasopressor use, comorbidities like hypertension, myocardial infarction, diabetes, peripheral arterial disease).

Time frame: Intraoperative and up to 30 days post-op.