Assessment of different positive airway pressure noninvasive ventilation modalities in patients with overlap syndrome

Background
Overlap syndrome (OS) is a challenging condition with an associated increased mortality. Noninvasive positive pressure ventilation is the main therapy in OS. Tri-level positive airway pressure (Tri-PAP) therapy is a new method of ventilatory support that was proposed to improve breathing during the cyclic breathing phases and correct the hypercapnia.


Objectives
To assess different noninvasive modalities of positive airway pressure including continuous positive airway pressure (CPAP), bi-level positive airway pressure (Bi-PAP), and Tri-PAP in the management of OS.


Patients and methods
This prospective interventional clinical trial was conducted on 45 patients with OS. After confirming the diagnosis of OS, patients were classified into three comparable groups, and in each group, we used one of the following three modalities of noninvasive ventilation: Tri-PAP, Bi-PAP, and CPAP. Arterial blood gas (ABG) was done after the use of the PAP. Data of sleep reports were recorded on each night and then analyzed.


Results
Patients were divided into three equal numbers and comparable groups in whom CPAP, Bi-PAP, and Tri-PAP were applied, correspondingly. Statistically significant improvement was observed regarding sleep parameters (apnea/hypopnea index, oxygen desaturation index, and snoring index) and ABG parameters [pH, partial pressure of carbon dioxide in arterial blood (mmHg), partial pressure of oxygen in arterial blood (mmHg), and arterial oxyhemoglobin saturation (%)] when Tri-PAP was compared with both Bi-PAP and CPAP.