In hospitals, ventilators are among the MVPs for patients in need of both acute and long-term care.
Ventilators keep people in comas alive, help those who cannot breathe get enough oxygen and those who have suffered heart attacks recuperate, and ease normal breathing in asthma patients, among a multitude of other uses.
Adding fuel to these concerns is a report, published this morning in the Journal of the American Medical Association, showing that the pandemic virus has already strained intensive-care unit resources in other North American countries.
Specifically, intensive-care units in Canada and Mexico were at full stretch during the peaks of the spring pandemic H1N1 flu outbreak, researchers said.
In Winnipeg -- site of the largest cohort of pandemic patients in Canada -- all intensive-care beds were occupied with H1N1 flu patients when the outbreak peaked in June, according to a study led by Dr. Anand Kumar, ICU attending physician for the Winnipeg Regional Health Authority.
And, in Mexico city, six major hospitals were so busy that admission to intensive care was delayed, and four patients died in the emergency department before they could get to the the ICU, according to a study led by Dr. Guillermo Domínguez-Cherit of Instituto Nacional de Ciencias Médicas y Nutrición "Salvador Zubirán."
The papers are the first to report on a large group of critically ill H1N1 patients treated during the early days of the pandemic in North America.
Meanwhile, Australian and New Zealand researchers reported last week that their intensive-care units were also under pressure as a result of the pandemic.
The papers underscore an unsettling reality -- that in an effort to ration resources during an emergency, health officials may be in the difficult position of determining, essentially, who lives and who dies.
"We have a lot of ventilators in the U.S., but somebody's on them all the time," said Arthur Caplan, director of the Center for Bioethics at the University of Pennsylvania. "You're basically talking about taking somebody off a ventilator to give it to somebody else."
Late last month, the Institute of Medicine released guidelines for crisis standards of care that included recommendations on how to allocate life-saving resources -- such as ventilators -- in an emergency while maintaining ethical standards.
"Depending on the disaster, ventilators are something you could need and could run out of," said Dr. Tia Powell, director of the Montefiore-Einstein Center for Bioethics and one of the authors of the IOM report. "But no one thinks that is likely with H1N1."
Other resources, Powell said, that may need to be rationed carefully include oxygen, tubing of various sizes and antibacterial or antiviral medications.
Public health experts agree that swine flu will not be an overwhelming pandemic in the way that the 1918 influenza pandemic, which killed more than 50 million people, was. Antiviral vaccine development is well under way, and public awareness about H1N1 influenza is increasing.
But disaster situations require doctors to make decisions where providing the best individual care may conflict with the duty to steward resources to save the greatest number of lives.
Part of the Institute of Medicine's potentially controversial guidelines recommends careful allocation of ventilators, which can be critical for those with swine flu but are limited in number and require skilled staff to operate. Hospitals may need to make those with acute conditions a priority over those with chronic conditions, such as cancer, when it comes to who gets a ventilator.
"It's loony, immoral madness not to plan for that kind of emergency," Caplan said. "But it's one thing to have a plan and another thing to have doctors comply."
Caplan said the conflict lies in a health care provider's ethical obligation to not abandon a patient he or she cares for. And if doctors won't reallocate the resources at their disposal, it can be difficult for a third party to force them.
In a declared emergency, it is often the responsibility of a hospital administrator -- who may or may not be a medical doctor -- to set reallocation protocols in motion.
Still, experts bristle at the thought that groups or individuals who are stewards of resources could be thought of as "death panels."
"The group providing the recommendations is not deciding who lives and dies," said Dr. David Cronin, director of liver transplantation at Froedtert Memorial Lutheran Hospital in Milwaukee. "They are setting a decision tree and allocation system to provide the scarce resources in as just and fair a way as possible. It is the disease that is responsible for the deaths ... I would consider these 'life panels.'"
While the IOM's report does not endorse a particular way to allocate ventilators, it does favor evidence-based triage over first-come, first-serve systems.
"During a catastrophic disaster with insufficient medical and health resources to meet patient needs, we shift our goal for maximizing individual outcomes to helping the most people we can in the entire population," said Dr. Kristi Koenig, director of Public Health Preparedness at the University of California at Irvine School of Medicine. "Therefore, if one person is in cardiac arrest and has almost no chance of survival despite aggressive care and 10 other people need a simple intervention such an unblocking their airway so they can breathe, we would save 10 people and provide only palliative [comfort] care to the person who has almost no chance of survival."
The report emphasized that hospital and state officials should strive to keep crisis standards as consistent as possible and as transparent as possible to help allay confusion in an emergency.
"An allocation system has to be transparent to be fair," said Robert Field, professor of law and health management and policy at the Drexel University School of Public Health. "Otherwise, lives could be saved, and lost, based on favoritism. We shouldn't base life and death decisions on rolling the dice as to where the closest ventilator is located."
The report also addressed potential legal concerns of health care professionals who provide care under duress, which Powell said was an emerging and controversial area of law.
"If you want health care providers to show up to work in a disaster, endure physical risk for themselves, work around the clock in austere conditions and take on hardship duties, you have to make sure their sacrifice doesn't leave them at unnecessary risk," Powell said. "If they are making good faith choices and following guidelines, they should be protected from unnecessary harm as well as unnecessary legal harm."
But Powell maintained that patients need to be legally protected as well if they receive negligent care or treatment from an unqualified person.
While neither state officials nor hospitals need to adhere to the guidelines outlined in the IOM, they may be a useful planning tool for the challenging decisions about resource allocation necessitated by pervasive situations, such as pandemic influenza, or catastrophic disasters, such as hurricane or earthquake.
"These guidelines can't be lightly invoked ... your whole facility has to be up against a wall," Powel said. "Disaster has to be declared by a government entity and even then you need permission to operate under a crisis standard of care."
ABC News' Courtney Hutchison contributed to this report.