Longer flights, more passengers with medical conditions raise risks

While airlines are meeting requirements for in-flight emergency oxygen, it may be time to review the standards and to upgrade the technology. Airliners are making longer flights and the passenger population is growing older, suggesting that more people may be flying with medical conditions that could result in the need for supplemental oxygen during the flight.

“It’s time to look at today’s requirements,” said Joan Sullivan Garrett, chief executive officer of MedAire. Her Tempe, Ariz.-based company provides in-flight medical support to client airlines, primarily through specialist physicians on-call to advise aircrews faced with in-flight medical emergencies.

“Many airlines are providing supplemental oxygen through their reservations departments, but some passengers are not disclosing their medical condition,” she added. Should such a passenger become stricken in-flight, the cabin attendants must rely solely on the supplemental oxygen equipment with which the carrier has equipped its aircraft as a matter of course.

Sullivan believes the circumstances are now such that an industry commitment is needed to deploy more modern technology. Indeed, she is not alone in this view. A 2001 report on the safety risk of in-flight oxygen by the Oxygen Working Group of the Flight Safety Foundation raised the issue, asking “if current oxygen systems are sufficient in scope and the training extensive enough to counter the new propensities for in-flight emergencies.” Five other experts, representing a spectrum of industry expertise, joined Garrett in authoring this report.

Many corporate aircraft are equipped to a higher standard, showing what can be done.

The cockpit crews, Garrett said, generally are provided with adequate emergency oxygen equipment. In a telephone interview, she focused her remarks on the emergency equipment cabin attendants may need in the event of a decompression, smoke and/or fire emergency, and on the equipment at hand for passenger first aid:

For cabin attendants: The walk around portable oxygen bottles (POBs) presently available for flight attendants, which some carriers provide in addition to the required portable emergency breathing (PEB) hoods, typically contain 360 liters (11 ft.3) of oxygen under pressure. However, the current POBs are not designed to use for on-demand purposes; rather, they flow continuously, delivering only 2-4 liters per minute (LPM).

“If the capability existed to have 100 percent oxygen on demand for fire fighting or smoke-filled environments or decompression, this POB would only last about 15 minutes,” Garrett said, adding, “That is, if you’re sitting down and reading a newspaper.” However, a cabin attendant is more likely to be actively involved in calming passengers, attempting to locate the source of smoke or actively engaged in fighting a fire – activities that accelerate the consumption rate.

It would be preferable, Garrett said, if the POBs provided 45 minutes to an hour’s supply of emergency oxygen for long-range aircraft performing over water or polar flights.

For passenger treatment: At the 2-4 LPM flow for POBs, it would be better to use a nasal cannula to deliver the oxygen rather than the “Dixie cup” mask. “In a serious medical emergency, it would be preferable to have a minimum flow capacity of 6 LPM, possibly up to 10 LPM by reservoir mask for treatment of frequent events like chest pain,” Garrett said. And supplemental oxygen is almost universally one of the first actions taken during an in-flight medical emergency to counter hypoxemia. “If the oxygen isn’t on [the passenger] by the time they call us, it is when our doctors get involved,” Garrett said.

Given the duration of some flights, and perhaps the need to continue the flight to reach an adequate medical facility, supplemental oxygen may have to be administered to a passenger for hours, not just for a few tens of minutes. Rather than carrying more oxygen bottles, Garret suggested that for this purpose “a therapeutic oxygen outlet could be a standard feature on all passenger- carrying aircraft.”

These outlets are being installed as an optional feature on more corporate aircraft, and might be offered as a manufacturer’s option for airliners.

Inadequate oxygen equipment could increase an operator’s liability exposure. Supplemental oxygen is an essential part of some of the most sophisticated “treatment modalities” on the ground. “The airlines are legally being measured against ground standards,” Garrett pointed out.

Given these developments, Garrett said the time has come for a reconsideration and review of emergency in-flight oxygen requirements and regulations. Some of the needed oxygen equipment is being manufactured for the medical industry, but not for the aviation industry. She pointed out that more older and ailing passengers are flying, increasing the need for adequate, reliable and properly administered supplemental oxygen during flight. The problem is not restricted to the old. Children with chronic pulmonary disease are flying.

The term “properly administered” oxygen relates to a training issue. Cabin staff may not be practicing oxygen-related drills often enough for assured proficiency. As an example, it may be useful to look at the time it takes for flight attendants to break out emergency or supplemental oxygen and get it to the passenger. >> MedAire, tel. 480/333-3700; http://www.medaire.com <<

The Edge of Danger

Hypoxemia: the state of oxygen deficiency in the blood, tissues, and cells, sufficient to cause impairment of body functions – essentially any condition that interferes with the normal path of oxygen to the cells.

  • Hypoxemia is a commonly occurring but rarely noted aspect of air travel. Identification of hypoxemia for the individual traveler remains difficult.
  • Cabin altitudes reach levels that can cause significant hypoxemia in a small subgroup of travelers.
  • Virtually every study regarding hypoxemia calls for administering oxygen during flight, and during nearly every area of rescue the most valuable therapeutic component was oxygen.

Source: In-Flight Oxygen: An Increasing Safety Risk, Flight Safety Foundation Oxygen Working Group Report, 2001