NEW ORLEANS (AP) – Patients are spending extra hours in the emergency room because there’s no room in the hospital for those already admitted from the ER, a new study finds.

Each patient “boarding” in the emergency department until a bed opens in the appropriate ward adds about 30 minutes to the average time spent in the ER by other patients, according to a report presented Sunday to the American College of Emergency Physicians.

That means an extra 21/2 hours if five patients are boarding; nearly 6 3/4 if there are 15 boarders, said Dr. Ted Chan of the University of California at San Diego.

The report adds details about the effects of a problem all too frequent at U.S. hospitals. Three-quarters of hospitals report at least two patients boarded in the halls on a typical Monday evening, according to a June report by the Institute of Medicine.

Dr. A. Brent Eastman, chief medical officer at ScrippsHealth in San Diego and co-author of the Institute of Medicine report, said last week that he thinks Chan’s findings are important: “It shows the domino effect – it is affecting all of the patients coming through that crowded emergency department.”

Chan, a professor of clinical medicine at UCSD and medical director of its hospital’s emergency department, said his next step will be to look at whether the delays affect patients with heart attacks, pneumonia and other conditions for which speedy treatment is vital.

His study covered six months at the USCD Medical Center’s emergency department, which sees about 40,000 patients a year.

It looked at time waiting to see a doctor, time spent as an ER patient, and time to get all the paperwork dealt with after being discharged by a doctor.

Time waiting to see a doctor rose about 4 minutes for each boarded patient – more than 40 minutes when the ER had the most boarders, Chan found. Each boarder added an average of nearly 11 minutes to actual treatment time, and more than 15 minutes to time between the time a patient was discharged and he or she could actually leave.

Stony Brook University Medical Center has for years had a different approach: If a patient admitted through the emergency department is going to be staying in a hallway, the best hallway is in the appropriate ward.

Not everyone is a candidate for the hospital’s “full capacity protocol,” which – among other things – calls for privacy curtains around hallway beds and for the patients in them to get flowers once they’re moved into a room. Patients must be in reasonably good shape for people who must be in a hospital. Ordinarily, two hall patients per unit is the maximum.

Of 6,049 patients seen over the 23 weeks from October 2005 to March 2006, 4,638 could be considered, 2,696 met criteria for hall placement, and 484 actually wound up in hallways, Dr. Peter Viccellio reported in a study to be presented Monday.

The New York State Department of Health endorses the practice as a temporary emergency measure during peak periods of overcrowding, according to a “guidance document” released in 2002 and posted on Viccellio’s “hospital overcrowding” Web site.

Chan said, “We’re not allowed to do that in this state yet, in California. But we think that’s the right move. I’m taking care of patients in the hallway of the ED. There’s no difference between my hallway and an inpatient floor hallway.”