Let’s simplify oxygen delivery devices. Nasal cannulas fit inside the patient’s nose to deliver a little extra FiO2, like for patients having chest pain. Simple face masks are great for patients needing extra FiO2 but tend to breathe through their mouths. Non-rebreathers have one-way valves preventing re-breathing room air thus delivering a very high amount of FiO2 in emergencies for patients in respiratory distress. Venturi masks are perfect for COPD patients because they deliver a very specific amount of FiO2. The respiratory drive for COPD patients is hypoxemia, so if we give them too much O2, they stop breathing! Trach masks fit over tracheostomy openings and deliver humidified O2. T-pieces are used for patients who have passed a series of weaning trials and are almost ready to come off the ventilator. CPAP and BiPAP give the patient positive airway pressure. “C” stands for continuous meaning the patient gets the same amount of pressure on inspiration and expiration. Sleep apnea patients use these at night. “Bi” means there are two levels of pressure. Patients with CHF exacerbations benefit from positive pressure via bi-pap. SIMV is synchronized intermittent mandatory ventilation and we use this to start ventilator weaning. In SIMV the patient gets a pre-set tidal volume on vent-initiated breaths but their own tidal volume on breaths they initiate. Finally, assist-control is maximum ventilator support where the patient gets a pre-set tidal volume on vent and patient-initiated breaths. We’ll see this used for newly-intubated, post-code patients for example.
Date Published - May 31, 2018
Date Modified - May 21, 2018