Presnted by: Dr. Abdullah Al-Harbi Supervised by: Dr. Wadha Al-Otaibi بسم الله الرحمن الرحيم.

Presnted by: Dr. Abdullah Al-Harbi

Supervised by: Dr. Wadha Al-Otaibi

الرحمن الله بسمالرحيم

The future of the cuffed endotracheal tube

Pediatric Anesthesia 2004

14: 38-42

Gavin F. Fine and Lawrence M Borland

Dept. of Anesthesiology, Children’s Hospital of Pittsburgh, USA.

Introduction

It has been traditionally taught that only uncuffed ETTs should be used

for intubation in children under age of 8 years regardless of

indication or duration of intubation.

Cont..Introduction

Recent literature suggests that the dictum to use only uncuffed ETTs in children may be oudated- Just

another myth of pediatric anesthesia.

Objectives of this Article

What is the basis of the teaching to use uncuffed ETTs in children?Alternatively, if the safety and

reliability of uncuffed ETTs is proved Why change?

Arguments for use of uncuffed ETTs in childrenThe major argument has been based on the fact that using an uncuffed ETT allows an ETT of larger internal diameter to be used. So lower resistance to airflow and less work of breathing in the patient who is breathing spontaneously , however this advantage doesn’t hold for ventilated patients.

Arguments for use of uncuffed ETTs in children

The second argumentTo avoid trauma to the subglottis caused by cuffed ETT.as it is the narrowest part of the airway.Battersby et al.1977, reported that prolonged nasoendotracheal intubation with uncuffed ETTs

did not lead to sbglottic stenosis.Black et al.1990, reported no evidence of subglottic stenosis in almost 3000 children managed long term with uncuffed ETTs.

Arguments for use of uncuffed ETTs in childrenSuch reports have supported the wide spread clinical acceptance of uncuffed ETTs as the standard of care for children whether for short or long term intubation.

Counterarguments to avoiding cuffed ETT in children

Although there is no counterargument to the advantage of using a larger size uncuffed tube to minimize the WOB in spontaneously breathing children.Most patients in the operating theatre and ICU who are intubated have some form of ventilatory support to over come resistance of ETT.

Counterarguments to avoiding cuffed ETT in children

There is no literature on adverse effects of using an ETT with smaller internal diameter in spontaneously breathing patients for short periods of time.

Trauma Argument: Studies have documented a causal relationship between the duration of intubation and the occurrence of laryngeal mucosal inflammation for cuffed as well as uncuffed ETTs.

Joshi et al. showed that the longer the duration of intubation the more severe the apparent damage to the laryngeal mucosa even when uncuffed ETTs were used.

Counterarguments to avoiding cuffed ETT in children

Counterarguments to avoiding cuffed ETT in children

So, The Risk of stenosis parallels duration of intubation for uncuffed as well as cuffed ETTs. And the occurrence of complications may be related to duration of intubation and not to the type of ETT.

Other studies show that ETT size , whether cuffed or not is the key factor in occurrence of complications.

Stocks stated that “ an appropriate sized ETT is fundamental to the success of prolonged nasotracheal intubation in children ”.

Stamm et al. showed that trauma is related to ETT size.

Counterarguments to avoiding cuffed ETT in children

The major arguments against cuffed ETTs are based on early experiences relating to laryngeal damage caused by the use of over inflated cuffed ETTs.which was reported by Hawkins and Honig,1977 and 1979.

.Counterarguments to avoiding cuffed ETT in children

Counterarguments to avoiding cuffed ETT in children

However in these reports the cuffed ETTs were of the High –pressure low –volume type. Newer types of cuffed ETTs are of the low-pressure high-volume type. Studies in which these types of tubes have been used show no difference in the rates of complications associated with long term use between cuffed and uncuffed ETTs. Deakers et al.1994, khine et al.1997.

Intraoperative and intensive care use of cuffed ETTs

Cuffed ETTs have several advantages over uncuffed ETTs for surgical anesthesia in children .

–More economical to use :because one may use lower fresh gas flow compared to uncuffed ETTs.–Leaking cuffed ETT can be managed by adding air to the cuff instead of laryngoscopy to place a different sized uncuffed ETT and multiple intubations are independent risk factor for trauma related to intubation.–Cuffed ETT may reduce the risk of aspiration and airway contamination.–Cuffed ETTs decrease air pollution.

Intraoperative and intensive care use of cuffed ETTs

Positioning the ETT to minimize the risk of mucosal damage can be difficult . The contours of the trachea and larynx are such that both cuffed and uncuffed ETTs exert maximal pressure on the posterolateral aspect of the laryngeal mucosa at the level of cricoid cartilage.

Intraoperative and intensive care use of cuffed ETTs

When an uncuffed ETT is used the tube not only exerts pressure posterolaterally but also exerts pressure where the tip touches the trachea anteriorly. James, recently suggested that the cuff on cuffed ETT may position the ETT away from the posterior wall and the tip away from the anterior wall of the trachea.

Precautions when using cuffed ETTs in children

When using cuffed ETTs for surgical anesthesia care must be taken not to inflate the cuff to a pressure of greater than 25cmH20. Care must be taken to maintain correct pressure especially when N2O is used. The cuff must be positioned below the level of cricoid cartilage, but not far inferiorly to the level that the tip enters bronchus.

Future Advances in ETTs

Several New Ultra Thin-walled cuffed ETTs are in the developmental stages. These ETTs have larger internal diameters compared with standard cuffed ETTs,which may obviate the argument againest using cuffed ETTs because of increased WOB.

Conclusions

A cuffed ETT is appropriate and should be the first choice when an ETT of greater than 3.5 mm inner diameter is contemplated for use. Advantages of using Cuffed ETTs.

Conclusions

Drawbacks to using an ETT of less than 3.5 mm inner diameter for prolonged periods include increased risk of tube blockage. Using smaller diameter ETTs increase WOB but this is overcome by appropriate ventilator settings.