Cuffed versus uncuffed endotracheal tubes for general anaesthesia in children aged eight years and under

Since the introduction of endotracheal intubation in paediatrics, uncuffed endotracheal tubes (ETTs) have been the standard of care for children under eight years old, based on the presumption that complications, particularly postoperative stridor, are higher with cuffed ETTs. The major disadvantages of uncuffed ETTs cited for this shift in procedure include the difficulty in achieving tidal volumes due to leakage around an uncuffed ETT. To seal the airway adequately, uncuffed tubes may need to be exchanged for another tube with a larger diameter, which sometimes requires several attempts before the appropriate size is found. Uncuffed tubes also allow waste anaesthetic gases to escape, contributing significantly to operating room contamination and rendering the anaesthetic procedure more expensive. Our review summarizes the available data, to provide a current perspective on the use of cuffed versus uncuffed endotracheal tubes in children of eight years old or less.

To assess the risks and benefits of cuffed versus uncuffed endotracheal tubes during general anaesthesia in children up to eight years old.

We searched CENTRAL, MEDLINE, Embase, CINAHL, LILACS and Google Scholar databases from their inception until March 2017. We also searched databases of ongoing trials, and checked references and citations. We imposed no restriction by language.

We included randomized and quasi-randomized controlled trials in which the effects of using cuffed and uncuffed tubes were investigated in children up to eight years old undergoing general anaesthesia. We excluded studies conducted solely in newborn babies.

We applied standard methodological procedures, as defined in the Methodological Expectations of Cochrane Intervention Reviews (MECIR).

We included three trials (2804 children), comparing cuffed with uncuffed ETTs. We rated the risks of bias in all three trials as high. Outcome data were limited. The largest trial was supported by Microcuff GmbH, who provided the cuffed tubes used. The other two trials were small, and should be interpreted with caution. Based on the GRADE approach, we rated the quality of evidence as low to very low.Two trials comparing cuffed versus uncuffed ETTs found no difference between the groups for postextubation stridor (risk ratio (RR) 0.93, 95% confidence interval (CI) 0.65 to 1.33; 2734 children; quality of evidence very low). However, those two trials demonstrated a statistically significantly lower rate of endotracheal tube exchange in the cuffed ETT group (RR 0.07, 95% CI 0.05 to 0.10; 2734 children; quality of evidence very low).One trial with 70 participants found that costs per case were lower in the cuffed ETT group (mean difference (MD) EUR 19.0 lower; 95% CI 24.23 to 13.77 lower; quality of evidence low), since the higher cost of the cuffed tubes may be offset by the savings made with anaesthetic gases.No clear evidence emerged to suggest any difference between cuffed and uncuffed tubes for outcomes such as the need to treat postextubation stridor with tracheal re-intubation (RR 1.85, 95% CI 0.17 to 19.76; 115 children; 2 trials; quality of evidence very low), epinephrine (RR 0.70, 95% CI 0.38 to 1.28; 115 children; 2 trials; quality of evidence very low) or corticosteroid (RR 0.87, 95% CI 0.51 to 1.49; 102 children; 1 trial; quality of evidence very low), or need for intensive care unit (ICU) admission to treat postextubation stridor (RR 2.77, 95% CI 0.30 to 25.78; 102 children; 1 trial; quality of evidence very low).None of the trials included in this review evaluated the ability to deliver appropriate tidal volume.

Implications for practiceWe are unable to draw definitive conclusions about the comparative effects of cuffed or non-cuffed endotracheal tubes in children undergoing general anaesthesia. Our confidence is limited by risks of bias, imprecision and indirectness. The lower requirement for exchange of tubes with cuffed ETTs was very low-quality evidence, and the requirement for less medical gas used and consequent lower cost was low-quality evidence. In some cases, tracheal re-intubation is required to guarantee an open airway when adequate oxygenation is difficult after removal of the tube, for a variety of reasons including stridor, muscle weakness or obstruction. No data were available to permit evaluation of whether appropriate tidal volumes were delivered. Implications for researchLarge randomized controlled trials of high methodological quality should be conducted to help clarify the risks and benefits of cuffed ETTs for children. Such trials should investigate the capacity to deliver appropriate tidal volume. Future trials should also address cost effectiveness and respiratory complications. Such studies should correlate the age of the child with the duration of intubation, and with possible complications. Studies should also be conducted in newborn babies. Future research should be conducted to compare the effects of the different types or brands of cuffed tubes used worldwide. Finally, trials should be designed to perform more accurate assessments and to diagnose the complications encountered with cuffed compared to uncuffed ETTs.