Temperatures hit 102 degrees (39 Celsius) during the final round as Tiger Woods claimed victory at Southern Hills Country Club.
Frank Mitchell, head of the tournament medical committee, told reporters so many people were being treated yesterday that it was hard to keep count.
''It was overwhelming in the last couple of hours,'' Mitchell said. ''It was like a war zone. People were out here for a long time and they wanted to stick around to see Tiger.'' Some 85 people were treated at the course yesterday, the hottest day of the tournament. Temperatures hit at least 100 degrees on each of the four days of the championship.
Nearly 40 people were hospitalised for heat-related complaints during the week, with one woman's vital signs being critical before she was revived and taken to hospital, Mitchell said.