During Oahu's Dec. 26 blackout, which left most of the island without power for 12 hours, hundreds of those relying on medical equipment had limited options: wait it out at home or wait it out in a busy hospital.

Toby Clairmont, director of Emergency Services for the Healthcare Association of Hawaii, said there were no reports of Oahu residents with serious health risks because of the blackout, but added that the consequences would have been greater if the power outage were longer.

Most medical equipment—from oxygen tanks to ventilators—has some sort of backup battery that automatically kicks in during power failures.

“;Once the power outage goes beyond four to six hours, the backup battery begins to die, and when they do, people don't know what to do,”; said Clairmont, who coordinates with all the hospitals during emergency situations. “;There's no place for these people to go other than hospitals. What's available today is not acceptable.”;

There was an influx of residents on medical equipment at hospitals during the blackout, Clairmont said. In one case, two residents went to hospitals without their machines because they did not know what else to do.

Clairmont suggests the state help create community-based centers during emergencies for residents to plug in their medical equipment.

“;One of the things we learned is we don't believe the reliability of our power system in Hawaii is going to get any better,”; Clairmont said. “;We did better this time than years ago, but there's still reoccurring issues that need intense work.”;

Clairmont will testify at a state Senate committee hearing this week to discuss the power failure. One of the things Clairmont will suggest is for officials to refrain from advising residents on life support systems to go to the hospital immediately.

“;The information that's given to the public needs to be more precise,”; Clairmont said.

The hospitals did not turn any of these patients away, but if the outage had lasted longer or if there were accidents, more critical patients would receive priority, Clairmont said.

Clairmont recommends that residents have a “;meaningful”; plan in case of emergencies—whether it involves going to a family member's home, relying on a generator or going to the hospital. If residents do need to go to a hospital, they should bring their medical equipment as well.

Hawaiian Electric Co. estimates that 800 customers rely on medical machinery at home.

Storms and natural disasters give the problem national scope.

When ice downed electric lines last month in Epping, N.H., police found 60-year-old Richard Lapoint dead, hooked to his powerless oxygen machine. The town's rescue workers had not known he depended on power.

A generator and stack of batteries could not keep up with Gatlan Graham's ventilator and other life-supporting equipment when Hurricane Ike knocked out power to his Houston home for 14 days in September. The family fled in search of electricity, spending more than $1,500 to keep the 17-year-old alive.

Roughly 2 million people in the United States use home oxygen machines, mostly “;concentrators”; that make oxygen on the spot as long as electricity flows.

At least another 10,000 people breathe with home ventilators, and thousands more have implanted heart pumps called VADs, or ventricular assist devices.

Millions more use other at-home equipment: dialysis machines, nebulizers, IV and nutrition pumps, CPAP breathing masks. But power failures bring the most immediate risk for users of ventilators, heart pumps and oxygen.

Utilities in every state operate “;medical priority lists”; designed to track who depends on power for life. But an Associated Press survey found huge state-to-state variations that suggest only a fraction of patients know they can sign up.

Illinois' biggest utilities together report 10,000 patients on critical-care lists, for example. Neighboring Indiana's biggest list carries just 2,000 names.

Even if patients did sign up, in large outages companies do not have the ability to restore power to one home before another down the street. So the lists could offer false hope.

This spring, the Food and Drug Administration plans to issue the first checklist for device recipients to receive when leaving the hospital.

“;It's incumbent upon us over the next 4 1/2 months, before we get into hurricane season again, to have a better plan than we had going into Ike,”; said Terry Moore, Houston's deputy emergency management coordinator.

Under consideration are mobile “;charging stations”; that could rotate through Houston neighborhoods for patients to recharge depleted batteries, or perhaps evacuating the power-dependent.

“;This is a huge vulnerability,”; added Dr. Lewis Rubinson of the University of Washington, who advises the government on disaster preparations and separately is preparing guidelines for emergency oxygen supplies. “;This is something that patients should demand.”;