Pressures within air‐filled tracheal cuffs at altitude – an <i>in vivo</i> study

Henning, Jeremy; Sharley, Peter; Young, Robert J.

doi:10.1111/j.1365-2044.2004.03609.x

Cited by 21 publications

(9 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The helicopter flew at a maximum altitude of 3,000 feet above sea level, with an average altitude of 1,931 feet and an average increase in altitude of 1,420 feet. The studies reporting clinically significant changes in tube cuff pressure reported these results at altitudes of at least 3,000 feet 1, 17. In this study, the mean altitude was only 1,931 feet with only one air-medical mission reporting a maximum altitude of 3,000 feet above sea level.…”

Section: Discussionmentioning

confidence: 50%

Altitude-Related Change in Endotracheal Tube Cuff Pressures in Helicopter EMS

Weisberg

McCall

Tennyson

2017

WestJEM

View full text Add to dashboard Cite

IntroductionOver-inflation of endotracheal tube (ETT) cuffs has the potential to lead to scarring and stenosis of the trachea.1, 2,3, 4 The air inside an ETT cuff is subject to expansion as atmospheric pressure decreases, as happens with an increase in altitude. Emergency medical services helicopters are not pressurized, thereby providing a good environment for studying the effects of altitude changes ETT cuff pressures. This study aims to explore the relationship between altitude and ETT cuff pressures in a helicopter air-medical transport program.MethodsETT cuffs were initially inflated in a nonstandardized manner and then adjusted to a pressure of 25 cmH2O. The pressure was again measured when the helicopter reached maximum altitude. A final pressure was recorded when the helicopter landed at the receiving facility.ResultsWe enrolled 60 subjects in the study. The mean for initial tube cuff pressures was 70 cmH2O. Maximum altitude for the program ranged from 1,000–3,000 feet above sea level, with a change in altitude from 800–2,480 feet. Mean cuff pressure at altitude was 36.52 ± 8.56 cmH2O. Despite the significant change in cuff pressure at maximum altitude, there was no relationship found between the maximum altitude and the cuff pressures measured.ConclusionOur study failed to demonstrate the expected linear relationship between ETT cuff pressures and the maximum altitude achieved during typical air-medical transportation in our system. At altitudes less than 3,000 feet above sea level, the effect of altitude change on ETT pressure is minimal and does not require a change in practice to saline-filled cuffs.

show abstract

Section: Discussionmentioning

confidence: 50%

Altitude-Related Change in Endotracheal Tube Cuff Pressures in Helicopter EMS

Weisberg

McCall

Tennyson

2017

WestJEM

View full text Add to dashboard Cite

show abstract

“…The effect of altitude on air-filled tracheal tube cuffs is well documented with recommendations to evacuate air from the cuffs after increases in altitude of as little as 2000 -3000 feet (10,11). However, we were unable to find documentation of the effect altitude has on the LMA cuff.…”

Section: Introductionmentioning

confidence: 61%

The Laryngeal Mask Airway at Altitude

Wilson

Sittig

Schears

2008

The Journal of Emergency Medicine

View full text Add to dashboard Cite

“…Had the pressures not been normalized the risk of tracheal injury might have been even higher. Several papers have demonstrated that ETTCP is affected by altitude changes23 when patients are transported by aeromedical transport modes 24–27. This analysis of patients presenting for HEMS transport demonstrated that the majority began with pressure outside the safe range.…”

Section: Discussionmentioning

confidence: 94%

Endotracheal Tube Cuff Pressures in Patients Intubated Prior to Helicopter EMS Transport

Tennyson

Ford-Webb

Weisberg

et al. 2016

WestJEM

View full text Add to dashboard Cite

IntroductionEndotracheal intubation is a common intervention in critical care patients undergoing helicopter emergency medical services (HEMS) transportation. Measurement of endotracheal tube (ETT) cuff pressures is not common practice in patients referred to our service. Animal studies have demonstrated an association between the pressure of the ETT cuff on the tracheal mucosa and decreased blood flow leading to mucosal ischemia and scarring. Cuff pressures greater than 30 cmH2O impede mucosal capillary blood flow. Multiple prior studies have recommended 30 cmH2O as the maximum safe cuff inflation pressure. This study sought to evaluate the inflation pressures in ETT cuffs of patients presenting to HEMS.MethodsWe enrolled a convenience sample of patients presenting to UMass Memorial LifeFlight who were intubated by the sending facility or emergency medical services (EMS) agency. Flight crews measured the ETT cuff pressures using a commercially available device. Those patients intubated by the flight crew were excluded from this analysis as the cuff was inflated with the manometer to a standardized pressure. Crews logged the results on a research form, and we analyzed the data using Microsoft Excel and an online statistical analysis tool.ResultsWe analyzed data for 55 patients. There was a mean age of 57 years (range 18–90). The mean ETT cuff pressure was 70 (95% CI= [61–80]) cmH2O. The mean lies 40 cmH2O above the maximum accepted value of 30 cmH2O (p<0.0001). Eighty-four percent (84%) of patients encountered had pressures above the recommended maximum. The most frequently recorded pressure was >120 cmH2O, the maximum pressure on the analog gauge.ConclusionPatients presenting to HEMS after intubation by the referral agency (EMS or hospital) have ETT cuffs inflated to pressures that are, on average, more than double the recommended maximum. These patients are at risk for tracheal mucosal injury and scarring from decreased mucosal capillary blood flow. Hospital and EMS providers should use ETT cuff manometry to ensure that they inflate ETT cuffs to safe pressures.

show abstract

Pressures within air‐filled tracheal cuffs at altitude – an in vivo study

Cited by 21 publications

References 8 publications

Altitude-Related Change in Endotracheal Tube Cuff Pressures in Helicopter EMS

Altitude-Related Change in Endotracheal Tube Cuff Pressures in Helicopter EMS

The Laryngeal Mask Airway at Altitude

Endotracheal Tube Cuff Pressures in Patients Intubated Prior to Helicopter EMS Transport

Contact Info

Product

Resources

About