Blackouts on Hawaii and across the nation are bringing attention to the need for emergency plans to help the increasing number of people who rely on electrically powered life-support equipment in their homes.

Utility companies in every state have lists of critical-care customers, but there appear to be gaps in the registries and networks that are supposed to help people on ventilators, heart pumps and oxygen devices when the power goes out.

In view of the prolonged electrical failures in Hawaii's population center as well as outages on the neighbor islands, state and county emergency agencies should devise aid and informational strategies to go along with conventional service programs.

Advances in medical technology have allowed more and more people to use assisting equipment in their homes. While hospitals, care homes and other facilities operate on their own generators in emergencies, most households aren't similarly prepared and even with batteries cannot keep equipment going for extended periods.

During the blackout across Oahu the day after Christmas, an influx of people on medical equipment arrived at hospitals, according to Toby Clairmont, director of Emergency Services for the Healthcare Association of Hawaii, which represents health care providers in the islands.

No one was turned away and there were no reports of health risks due to the outage, but had there been a wider disaster, their presence could have made a bad situation worse. If the outage lasted longer - days instead of 12 to 18 hours - the consequences could have been greater.

Clairmont suggests the state create community-based centers, such as shelters or fire stations, where power-dependent residents can plug in their medical equipment. Emergency officials should consider this proposal.

A survey by the Associated Press found huge variations in utility companies' medical priority lists that are supposed to track who depends on power for life-support machinery, indicating the lists are incomplete and that many people aren't even aware of them.

In any event, companies don't have the ability to restore power one home at a time. However, the lists can direct emergency workers and be used to provide equipment-dependent people with instructions.

Hawaiian Electric Co., which estimates that 800 of its customers rely on medical equipment at home, says it cannot avoid power failures caused by uncommon events like the multiple lightning strikes it suspects caused the most recent blackout. With that in mind, people who need power for life-support devices should have contingency plans, either generators or alternate plug-in sites if the outage isn't widespread.