Endotracheal Tube and Neonate

Archives of Otolaryngology -- head&neck surgery. vol.117 No.8,Augest 1991

100% with a leak pressure of less than 20 cm H2O --successfully extubated

100% with a leak of greater than 30 cm H2O --failure

60% with a leak pressure in the range of 21 to 30 cm H2O --successfully extubated

Archives of Otolaryngology -- head&neck surgery. 119(8):815-9, 1993 Aug.

Risk factors for acquired laryngotracheal stenosis in newborn infants are poorly known.

The size of the endotracheal tube appears to be a major risk factor for acquired laryngotracheal stenosis in the neonate.

Pediatric Pulmonology. 7(2):116-20, 1989

37 month period flexible fiberoptic bronchoscopies in 77

neonates Bronchoscopy has been found valuable in

the management of emergency situations such as suspected tube blockage or malposition and difficult intubations.

AANA Journal. 66(3):299-303, 1998 Jun.

The traditional age-base(AB) formula;(age in year+16) divided by 4

Using the Broselow pediatric resuscitation tape.

The AB formula is reliable and easily applied.

Age is not available, the Broselow pediatric resuscitation tape allows reliable.

Anesthesia & Analgesia. 97(6):1857-1858, 2003

ETT allow small air leak at peak inflation pressure of 20-30 cm H2O.

Inspiratory and expiratory tidal volume(ITV and ETV) 10-15 ml/kg tidal volume and an appropriate RR Apply PEEP of 4-5cm and increase gradually(1-2cm H2O

at a time) until the PIP to 25 cm H2O(PEEP<10 cm H2O)

A difference of 10% tidal volume but less than 5ml between the ITV and ETV→ suitability of the ETT.

No further increase in the difference between the ITV and ETV, the ETT is deemed an oversized one.

Endotracheal Intubation

and Tracheal Stenosis

Textbook-Miller’s AnesthesiaAge of Patient I D of ETT (mm)

Premature(<1250g) 2.5

Full term 3.0

1 ~ 6 m 3.5

6 ~ 12 m 4.0

4 yr 5.0

6 yr 5.5

8 yr 6.0

10 yr 6.5

12 yr 7.0

> 14 yr 7.0 female ; 7.5 male

Uncuffed endotracheal tubes have been used in children younger than 6 ~ 8 years

Gas leak in the peak inflation pressure：15~20 cmH2O (20~30 cmH2O)

If no leak is detected in the pressure of 40 cmH2O, shift to smaller size.

Cuff pressures that afford good (but not perfect) protection (20 to 25 mm Hg) are just below the perfusion pressure of the tracheal mucosa (25 to 35 mm Hg).

Laryngotracheal Stenosis

The most common cause : ischemia secondary to intubation.

SitesAdult : glottis, posterior siteChildren : subglottis

Risk factorsCuff pressure Tube size Tube shape Intubation

durationRepeated

intubation

GE reflux, Bacterial

colonization, Systemic illness MalnutritionHypoxia, AnemiaMovement

Normal Subglottic Area

elliptical congenital subglottic stenosis (SGS)

Spiral subglottic stenosis

4-month-old infant with acquired grade III subglottic

stenosis from intubation

Literature Search

12% incidence of laryngeal stenosis in patients with tracheal intubation for 11 days or longer, a 5% incidence between 6-10 days of intubation, and a 2% incidence with less than 6 days intubation.

Whited RE. Laryngeal dysfunction following prolonged intubation. Ann Otol Rhinol Laryngol 1979;88:474-8

19% of the patients who had translaryngeal intubation developed significant stenosis, which was defined as >>10% reduction in the air column diameter, with stenosis occurring either at the subglottic area or the cuff.

Stauffer JL, Olson DE, Petty TL. Complications and consequences of endotracheal intubation and tracheotomy: a prospective study of 150 critically ill

adult patients. Am J Med 1981;70:65-76

Almost all patients who undergo translaryngeal intubation suffer some degree of stenosis

Heffner JE. Timing of tracheotomy in ventilator-

dependent patients. Clin Chest Med 1991;12:611-25

Histologic study demonstrated 1.Focal or complete loss of mucosal epithelium

in contact with the orotracheal tube for even one hour.

2.The ischemic nature of the necrosis.

3.That perichondritis of the vocal process is increasingly frequent after 48 hours of intubation.

4.The infestation of the ulcer site by microorganisms is common after 24 hours of intubation.

( 15 min ~ 176 hrs of intubation duration )William H. Donnelly. Histopathology of endotracheal

Intubation. An Autopsy study of 99 cases. Arch Path.

88;1969.

Contencin P, Narcy P. Size of endotracheal tube and neonatal

acquired subglottic stenosis. Arch Otolaryngol Head Neck Surg.

1993 Aug;119(8):815-9

In the 1970s and 1980s, estimates of the incidence of subglottic stenosis were in the range of 0.9% ~ 8.3% of intubated neonates.

All studies published after 1983 reported an incidence of neonatal subglottic stenosis as < 4.0%, and all studies published after 1990 reported an incidence as < 0.63%.

The current incidence of neonatal subglottic stenosis is likely between 0.0% ~ 2.0%.

Walner, David L.; Loewen, Mark S. ; Kimura, Robert E. Neonatal Subglottic Stenosis-Incidence and Trends.

Laryngoscope. 111(1):48-51, January 2001