Frequency of suctioning inside the tube that is used to ventilate newborn babies

Review question

We reviewed the evidence about the effects of different strategies in the frequency of suctioning of newborn babies that are on ventilators. Our main interest was prevention of lung damage.

Background

Newborns might need help with breathing as their lungs are still maturing. An airway catheter (tube) is inserted into the mouth or nose in order to maintain an open airway (patency) in newborns who are unable to breathe on their own. This procedure is called endotracheal intubation. Endotracheal tube suction is necessary to clear secretions and to maintain airway patency, therefore ensuring that the baby receives enough oxygen. The goal of endotracheal intubation suction should be remove as much of the secretions as possible with minimal side effects associated with the procedure. However, suctioning causes stress, pain, and inflammation (swelling) of the windpipe in newborns. The optimal frequency of suctioning has not been defined. Suctioning inside the airway tube might be performed 'as scheduled' by the specialist or only 'as needed'. Moreover, the 'as scheduled' approach might be more or less frequent. We explored the current evidence, up to October 2015, supporting one schedule or another.

Study characteristics

We searched medical databases for clinical studies comparing different strategies regarding the frequency of endotracheal tube suction in newborn babies on ventilators. We found only one study recruiting 97 newborns with bodyweights under 2.5 kg (these are called low birthweight infants). Suctioning was performed every six or 12 hours during the first three days of life.

Key results

There were no important differences on the time the babies were on the ventilator, occurrence of pneumothorax (collapsed lung), need for ventilation or oxygen at more than 30 days, bleeding in the brain, and death in the first month of life. In addition, the study reported no side effects.

Quality of the evidence

We only identified one study, which was conducted in 1987 and 1988 and had several shortcomings. We cannot advise health professionals and parents about the optimal frequency of suctioning when newborns are ventilated.

Authors' conclusions: 

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.

Read the full abstract...
Background: 

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.

Objectives: 

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.

Search strategy: 

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.

Selection criteria: 

Randomized, quasi-randomized, and cluster randomized controlled trials comparing different strategies regarding the frequency of ETT suctioning of newborn infants receiving ventilator support.

Data collection and analysis: 

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.

Main results: 

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.