Eight asthma myths you need to recognize

When treating asthmatics, keep in mind these eight myths:

Myth 1: If patients have already used beta agonists at home, there is no reason to give beta agonist therapy. "Failure of beta agonist therapy at home does not translate to failure of beta agonist in the ED," says Rita Cydulka, MD, residency director for the department of emergency medicine at Case Western Reserve University in Cleveland.

Myth 2: A silent chest is not an ominous sign. "Those people are probably near moribund," Cydulka says. "When you listen to the chest of asthmatics, you usually hear wheezing. But sometimes you hear nothing, which means they’re so obstructed they aren’t able to generate a sound. You need to be very worried about these patients."

Myth 3: A normal PCO2 in an asthmatic that is breathing rapidly is not cause for concern. "Actually, you should be concerned. One would expect that an asthmatic with a rapid respiratory rate would have diminished PCO2," says Cydulka. "You would see a PCO2 of 40 to 42 in an otherwise healthy person without asthma."

But in an asthmatic with an increased respiratory rate, that is considered a CO2 retention, because they should have a PCO2 in the 25 to 30 range, Cydulka explains. "If the level is normal, it means they are failing to blow it off and having signs of ventilatory failure," she says.

Myth 4: You shouldn’t treat pregnant asthmatics with steroids. "Actually, the opposite is true," advises Cydulka. "You need to be very vigilant in caring for pregnant asthmatics and give them steroids very readily. Asthmatics who do poorly have lots of maternal and fetal complications. They tend to be eclamptic and wind up with abruptions and babies small for gestational age babies. So you need to be extra careful rather than withholding treatment from them."

Myth 5: Clinical judgment and physician exam are just as good an indicator of the state of the airways as pulmonary functions. "We have done studies where physicians were asked to guess the pulmonary functions of patients, and the results were not good," Cydulka says. "You really need pulmonary functions to assess the level of obstruction. There have been multiple studies showing that vital signs and breath sounds normalize long before pulmonary function does."

Myth 6: Metered-dose inhalers (MDIs) don’t work as well as nebulized aerosols during exacerbation. "If patients are properly educated in the correct use of MDIs or given a spacer device to use, MDIs are just as effective for treating exacerbation as aerosolized beta agonists," says Cydulka.

• Myth 7: Most asthma patients will not be able to live a normal life. That is a common misconception, says Richard Nowak, MD, FACEP, vice chairman of the department of emergency medicine at Henry Ford Health System in Detroit. "The guidelines clearly show that when asthmatics are appropriately managed, they can live a totally normal life," Nowak says. "That includes not waking up at night, being able to exercise, and not being impaired in lifestyle. That is a realistic goal with appropriate strategies and avoidance of triggers."

Myth 8: Asthmatics don’t belong in the ED. "It’s not that every asthmatic is incorrigible. Some can’t get to see their doctors; others are mismanaged or just don’t take their meds," says Nowak. "If we can’t educate people to take inhaled corticosteroids steroids, maybe it’s our problem and we’re not doing it right. It’s a real challenge, but the more you know about the disease, the better you can educate the patient. You don’t want people to stay at home and die of an acute exacerbation of the disease."

Asthmatics with very severe exacerbations should never hesitate to come to the ED, stresses Cydulka.

"When you have an asthmatic with acute ventilatory failure and respiratory failure, you may need to intubate and ventilate to maintain their oxygenation. However, that is not a cure, and it’s fraught with many complications," she says. "Those are very frightening patients."