Blood Flow

Large doses of caffeine are known to constrict blood vessels supplying the brain. Now researchers have found that going without the brew for about a day and half increases blood flow to the brains of heavy coffee drinkers 30% more than it does in light coffee drinkers. "It's way above what a person normally experiences," study coauthor Dr. Paul J. Laurienti says of the increased blood flow. The surge may explain the headaches that plague people when they first give up coffee.

Elderly people who drink moderately are less likely to suffer dementia than teetotalers, though seniors who drink too much add to their risk, researchers said Tuesday. Seeking to explain their findings, the researchers said consuming moderate amounts of alcohol prevents hardening of the arteries that leads to damaging strokes, lessens the risk of brain lesions and helps blood vessels to function.

Brandy Eddins, 14, lost her forearm in a wood-shop accident on Jan. 11. Later that day, in surgery at Hartford Hospital that went late into the night, Dr. Andy Caputo reattached the forearm, which had been cut midway between wrist and elbow. The difficult surgery was a technical success, and there was every reason to be optimistic. But when it comes to reattaching upper limbs--"replanting," in medical jargon--the body has evolved a response that even sophisticated medicine can't always overcome.

Among the directorial challenges Dave Barton faced in staging "Frankenstein in Love," a sometimes funny, sometimes philosophical but altogether gory play by horror master Clive Barker, was the careful, trial-and-error calibration of how much blood to spill. During rehearsals, Barton said, spectators in the front row of the Rude Guerrilla Theater Company's tiny Empire Theater were getting splashed. He gradually found ways to make the spurting more sparing.

J. Harold Wayland, 91, Caltech scientist known internationally for his research on blood flow. Wayland taught engineering and applied science at Caltech from 1949 to 1979. He was an expert on blood flow whose research examined the impact of diabetes mellitus on circulation and the interaction between blood and tissues in the smallest vessels in the body. He also pioneered the development of microscopic measurements to investigate fundamental life processes.

The Food and Drug Administration on Wednesday approved a device designed to help women achieve sexual satisfaction, marking the first time that the federal government has licensed an aid for women with sexual dysfunction. In recent years, the market has seen a spate of products--including the blockbuster drug Viagra--aimed at enhancing sexual performance, but the emphasis has been primarily on helping men. The Eros device, made by UroMetrics Inc. of St. Paul, Minn.

Yale University scientists who monitored Mt. Everest climbers say they have new clues to what causes a rather ordinary affliction--the high-altitude headache. The evidence indicates that people don't get headaches at high altitudes because of less oxygen in the brain, as the researchers had believed, but because of overwhelming blood flow to the brain. "We know categorically that in high-altitude headaches, the mechanism is different than what we thought all along," said Dr.

Riding a typical bike seat can lead to impotence, researchers say. And as that word gets out, sales of nontypical bike seats have been increasing. Sitting on an ordinary narrow, pointed seat can crush an artery that controls the ability of the penis to fill with blood, said researcher Pedram Salimpour of Boston University School of Medicine. "When you sit on a bicycle seat, you are sitting on the artery," Salimpour said. "God did not mean for you to sit on a bicycle seat."

The medical odyssey of 14-year-old Jeff Thornton, who died after developing gangrene from frostbite, is a testament to how exposure to severe cold can lead to infection. Exposure to cold shrinks blood vessels in the feet and hands, pinching off circulation and leaving the limbs without enough blood flow to fight infection in those areas. Tissues also die because of the lack of blood, providing a fertile breeding ground for bacteria.

Dr. John Reinisch was about to sit down to a Mother's Day dinner with his family when he received a distressing call from Childrens Hospital, where he is chief of the plastic surgery unit. A 4-year-old boy's arm had been severed by a washing machine and he was at the hospital awaiting surgery. Reinisch was on call that night, so he raced to the hospital and examined the boy. He told the boy's parents that he would do his best, but he was very doubtful that he could successfully reattach the arm.