Background: 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.
Objectives: This study aimed to evaluate the effct of closed tracheal suction system (CTSS) versus open tracheal suction system (OTSS).
Patients and Methods: 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.
Results: Drainage of subglottic secretions decreased the incidence of VAP (P < 0.05). Also type of the pharmacologic medicine for stress
ulcer prophylaxis has signifiant effct 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 signifiant effct 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 humidifir decreased this risk.
Conclusions: 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.
Keywords:Intensive Care Unit; Suction; Pneumonia