Ventilator-associated pneumonia in patients admitted to intensive care units, using open or closed endotracheal...

Critically ill patients under mechanical ventilation require frequent suctioning of airway secretion. Closed suction permits suctioning without disconnection from ventilator; so it might decrease hypoxemia and infection rate.

This study aimed to evaluate the effect of closed tracheal suction system (CTSS) versus open tracheal suction system (OTSS).

This is a prospective randomized study, which was carried on 100 patients in surgical Intensive Care Unit requiring mechanical ventilation for more than 48 hours from June 2012 to November 2013. In two groups, suction was performed based on the patients' need as well as physician's or nurses' decision on tracheal secretions. Patients randomly allocated into two groups (50 patients each): CTSS group and OTSS group. Patients were monitored for developing ventilator-associated pneumonia (VAP) during the study. Throat samples were taken on admission and two times per week from each patient. Tracheal samples were performed during endotracheal intubation, two times per week during mechanical ventilation and during extubation.

Drainage of subglottic secretions decreased the incidence of VAP (P < 0.05). Also type of the pharmacologic medicine for stress ulcer prophylaxis has significant effect on VAP incidence. Among the patients in OTSS and CTSS groups, 20% and 12% developed VAP, respectively. Use of CTSS compared with OTSS did not show statistically significant effect on VAP incidence in multivariate analysis; however, OR (odds ratio) tended to identify OTSS as an exposure factor for the development of VAP (OR = 1.92; CI = 0.45-8.30; = 0.38) compared with the CTSS. Higher levels of APACHE II score, sinusitis and tracheostomy put the patients at the risk of VAP. However, using heat and moisture exchanger (HME) instead of humidifier decreased this risk.

Based on the results obtained from our study, impact of suctioning is similar between CTSS and OTSS regarding the occurrence of VAP. It seems that physicians must consider many factors such as duration of mechanical ventilation, comorbidities, oxygenation parameters, number of required suctioning, and the cost prior to using each type of tracheal suction system.