Non-conventional Modes of Mechanical Ventilation

Abstract

MV is a lifesaving intervention for patients with respiratory failure to maintain essential physiological functions of the organs of the body by oxygenation and ventilation. Effective management of patients requiring MV depends on the clinician’s knowledge of normal pulmonary physiology and mechanics of breathing. MV also requires monitoring of the patient response to assess the change in lung elastance and resistance to avoid the complications of barotrauma and VILI.

The conventional modes found to be inadequate to oxygenate patients with ALI or ARDS which has prompted extensive efforts to identify what are now known as alternative modes of ventilation. HFOV and APRV are the two commonly used alternative modes of MV in this patient population.

These alternatives modes use much smaller tidal volumes than conventional ventilation. So it avoids alveolar overdistentionand the potential risks of MV complications. The high mean airway pressure can improve the lung recruitment by prevent the alveolar collapse. It improves V/Q matching by ensuring uniform aeration of the lung.

In contrast, conventional mechanical ventilation complications, related to the intubationas well as to the risk of developing VAP.NIV was invented in the nineteen-eighties, which use a nasal or face mask instead of the endotracheal tube.

With the high mortality rate of ARDS, some centers proposed establishing an extracorporeal circuit, combining a centrifugal pump and a membrane oxygenator, assuring extracorporeal pulmonary assistance. Also LV is a technique of MV in which the lungs are insufflated with PFCs as inert carrier of O2 and CO2for the treatment of ALI.

TGI is supporting unconventional ventilation techniques, based on fresh air delivery to the endotracheal tube or to the airways using a thin TGI catheter. TGI increases exercise tolerance and reduces dyspnea in spontaneously breathing patients with chronic respiratory disease.