Experimental, autopsy and clinical studies show that prolonged intubation can lead to edema, inflammation and ulceration esp. at the level of the cords and at the cuff site 21/39(54%) intubated patientrs had ulcers on the posterior vocal cords and 49/52 (93%) had mucosal inflammation and/or edema at autopsy 15
One of the most frequent complications following tracheal extubation Incidence 2-22% of patients intubated >24 hrs 1,2 Increases mortality rate and prolongs ICU stay3,4,5 Typically occurs shortly after extubation6,7,8 Usually occurs after 36 hrs of intubation6 One of the main causes of resp distress after extubation3 In a series of 700 consecutive extubations, 5 percent developed clinically significant laryngeal edema. However, only 1 percent of patients required reintubation, all of whom had been intubated for more than 36 hours (Darmon)
Heliox Normal laminar flow is dependent on gas viscosity; when airway obstruction is present, flow is turbulent Turbulent air flow is dependent on gas density Heliox has a density 1/3 of oxygen or air so it decreases airway resistance and improves ventilation