By Joel Thomas, CBS 11 News

FORT WORTH (CBSDFW.COM) – A half-dozen dispatchers, surrounded by multiple computer screens which cast soft, colorful light on their faces, answer Fort Worth’s emergency medical calls at Medstar’s headquarters. From here, they’ll dispatch ambulances several hundred times a day.

“Is he conscious and alert?” a dispatcher asks into her headset microphone.

Medstar dispatchers are receiving up to 15% more emergency calls than usual during our arctic blast.

But they’re probably not the type of calls you’d expect.

“We’re only seeing about a 41% increase for traffic accident related calls which is very low for this kind of an incident,” said Suzy Miller, a spokeswoman for Medstar.  Emergency crews say drivers seem to have heeded warnings and stayed home. But calls for respiratory problems skyrocketed: up by 96%.

“Folks with asthma, congestive heart failure, they can experience problems when we have an abrupt shift in the weather like this,” said Miller. “It has to do with the pressure and the temperature of the air and that sort of thing.”

And medical personnel say dramatic atmospheric pressure changes also help account for a 150% increase in the number of birth and pregnancy related calls.

Perhaps not surprisingly — considering the icy sidewalks and streets — the calls for people who’d fallen soared 192%.

And when they’re making those calls, ambulance drivers are told not to use their lights and sirens when responding.  The icy roads are too dangerous.

“We try to institute some good driver training– tell those people to get control of those emotions, increase the following distance of the car in front of them,” said Mike Shelton, Medstar Risk and Safety Manager.