Matteo Bruschettini, Simona Zappettini, Lorenzo Moja, Maria Grazia Calevo

Endotracheal suctioning consists of the mechanical aspiration of pulmonary secretions from the endotracheal tube (ETT) to prevent obstruction. The optimal frequency of ETT suctioning has not been defined. To determine the effect of specific ordered frequency of ETT suctioning ('as scheduled') versus ETT suctioning only in case of indications ('as needed') and of more frequent ETT suctioning versus less frequent ETT suctioning on respiratory morbidity in ventilated newborns. We used the standard search strategy of the Cochrane Neonatal Review group to search the Cochrane Central Register of Controlled Trials (CENTRAL 2015, Issue 10), MEDLINE via PubMed (1966 to 31 October 2015), EMBASE (1980 to 31 October 2015), and CINAHL (1982 to 31 October 2015). We checked the reference lists of retrieved articles and contacted study authors to identify additional studies. We also searched clinical trials databases, conference proceedings, and the reference lists of retrieved articles for randomized controlled trials and quasi-randomized trials. Randomized, quasi-randomized, and cluster randomized controlled trials comparing different strategies regarding the frequency of ETT suctioning of newborn infants receiving ventilator support. We used the standard methods of the Cochrane Neonatal Review Group. Two review authors independently extracted data and assessed the risk of bias of trials. The primary outcome was bronchopulmonary dysplasia or chronic lung disease. We identified one randomized controlled study recruiting 97 low birthweight infants that met the inclusion criteria. The study was conducted in the UK in 1987 and 1988. Randomized infants received ETT suctioning every six or 12 hours during the first three days of life. The quality of reporting was limited and we rated the trial at high risk of bias. Furthermore, the trial lacked adequate power. There were no statistically significant differences in any of reported outcomes: bronchopulmonary dysplasia (defined as oxygen at more than 30 days; risk ratio (RR) 0.49, 95% confidence interval (CI) 0.20 to 1.20); incidence of pneumothorax (RR 0.70, 95% CI 0.24 to 2.05); intraventricular hemorrhage (RR 1.12, 95% CI 0.44 to 2.85); neonatal death (RR 1.40, 95% CI 0.58 to 3.37); and time on ventilation (median time 39 hours in the 12-hourly group and 28 hours in the six-hourly group; RD not applicable for this outcome as mean and standard deviation were not reported). Tests for heterogeneity were not applicable as only one study was included. There was insufficient evidence to identify the ideal frequency of ETT suctioning in ventilated neonates. Future research should focus on the effects in the very preterm newborns, that is, the most vulnerable population as concerns the risk of both lung and brain damage. Assessment should include the cases of prolonged ventilation, when more abundant, dense secretions are common. Clinical trials might include comparisons between 'as-scheduled' versus 'as-needed' endotracheal suctioning, that is, based on specific indications, as well frequent versus less frequent suctioning schedules.