EMS is called to the house of a 12-year-old male patient in severe respiratory distress. He has a history of asthma and is on multiple controller medicines, including Flovent, Singulair and albuterol sulfate. On arrival to the house, you find the patient seated in a tripod position. He's tachypneic and in severe distress. His mother states he developed cold symptoms yesterday and has used his albuterol inhaler multiple times today without improvement.
A quick set of vital signs show a heart rate of 150, respiratory rate 45, BP 120/70 and oxygen saturations of 83% on room air. Examination of the patient shows him to have significant intercostal, abdominal and supraclavicular retractions. He also has diminished breath sounds bilaterally with only a faint expiratory wheeze. When you ask him to recite the alphabet, he can only get to the letter "D" before becoming exhausted.
What's the proper treatment during your 15-minute ride to the emergency department (ED)?
Asthma is a common childhood illness that affects nearly 9% of all children. The treatment of patients in severe status asthmaticus must be prompt and efficient. For most patients with mild to moderate asthma exacerbation, EMS treatment with nebulized albuterol is all that's required. Once the patient gets to the hospital, this therapy will be continued, and the patient will usually be discharged with a five-day course of steroids.
Therapy is dramatically different for the patient who is in extremis. In these critically ill patients, it's imperative that we be aggressive from the start. The prompt treatment of pediatric patients with severe asthma exacerbations starts in the field. It's the job of the EMS provider to determine the severity of the exacerbation and initiate life-saving treatments.
Determining the severity of the exacerbation is best done by such objective clinical findings as tachypnea, hypoxia, the presence of wheezing and retractions, and the amount of dyspnea present. The more positive the findings, the more severe the exacerbation.
In a pediatric patient with a severe asthma exacerbation, treatment should be initiated immediately on EMS arrival. This treatment consists of five potentially life-saving interventions. The speed at which they're initiated could determine whether the patient requires intubation or is able to maintain an airway on their own.
1. Secure the ABCs: As with any critical patient, securing the ABCs and placing the patient on a monitor should always be the first step. Pay particular attention to the patient's oxygen saturation because those with hypoxia are more likely to require systemic medications and admission to the hospital. Oxygen acts as a bronchodilator and should be applied soon after contact with the patient.
2. Administer albuterol (or albuterol and ipratropium) nebulizer treatment. Albuterol is an effective bronchodilator because of its direct action on beta-two receptors. Albuterol is often co-administered with ipratropium in the form of a Duoneb. The early and combined use of these medicines is effective and can decrease the need for hospitalization. The patient should be evaluated after every single-dose nebulized treatment. If the patient is still wheezing, repeat the treatment. There's no limit to the number of nebulized treatments a patient can receive. All patients will become tachycardic during their treatments, but this should not prevent further beta agonist therapy.
3. In patients with poor air movement, administer intramuscular epinephrine. In such patients, the delivery of aerosolized beta agonist to the distal bronchioles will be poor. For this reason, an intramuscular dose of epinephrine 1:1000 at 0.01 mg/kg (with a maximum dose of 0.5 mg) should be administered. Epinephrine is a potent alpha and beta agonist and is an effective bronchodilator. Intramuscular delivery of the epinephrine assists with bronchodilation throughout the lung tissue. In younger children, the medicine should be administered in the lateral thigh for optimal drug delivery. In older patients, the deltoid can be used.
4. Establish an IV and administer magnesium sulfate. Magnesium acts as a smooth muscle relaxant and is thought to promote bronchodilation. In severe exacerbations, several studies have suggested it may improve lung function for children and decrease admission. A dose of 50Ï75 mg/kg IV over 20 minutes is the generally accepted dose.
5. Consider intravenous epinephrine. In refractory patients who are not improving with IM epinephrine and IV magnesium, life-saving therapy with IV epinephrine may be indicated but only if expertly and carefully done. IV epinephrine must be given very cautiously and slowly. Add 1 mg of epinephrine (1 mg in 1 cc, 1:1000 dilution) to an IV bag of saline or D5W, and run this drip through a microdrip chamber at 15 micropdrops per minute. (This is .025 cc and contains one microgram of epi.) Piggyback this slow drip into a high-flow IV so it can get into the patient's circulation as quickly as possible. The drip should be titrated to effect at one-minute intervals. Usually, 15Ï30 drops per minute (1Ï2 micrograms of epi per minute) will provide dramatic relief. Slow or discontinue the drip as the patient improves or if cardiac toxicity occurs. Never give the epi by IV push, or ventricular tachycardia/ventricular fibrillation may occur without warning.
Although corticosteroids are a mainstay of treatment for status asthmaticus, many EMS agencies don't carry these medicines because the maximal effect is not seen until a few hours after administration. It's perfectly acceptable to wait until arrival at the ED to administer them to the patient.
Two therapies that are gaining popularity and have been shown to help in severe exacerbations are nebulized epinephrine and BiPAP. Nebulized 1:1000 epinephrine provides pure vasoconstrictor effects and acts as an effective bronchodilator and pulmonary vasodilator, thereby improving air movement and oxygen delivery. Recent studies have also shown that use of BiPAP in patients who don't respond to the first-line therapies described above improves delivery of bronchodilators and can prevent the need for intubation.
In pediatric patients in severe status asthmaticus, aggressive treatment should begin immediately on EMS arrival. Five steps should be initiated to prevent progression to respiratory failure: Place the patient on a full monitor and oxygen; start the patient on albuterol (or albuterol plus ipatropium) through a nebulizer; give epinephrine 1:1000 0.01 mg/kg IM (max 0.5 mg); administer magnesium sulfate 50Ï75 mg/kg IV over 20 minutes; and consider IV epinephrine with 1 mg in 250 cc at 15 microdrops per minute. --JEMS
Mark Meredith, MD, is an assistant professor of pediatrics and emergency medicine at Vanderbilt University Medical Center. He serves both as the director of pediatric EMS at Vanderbilt Children's Hospital and as an assistant medical director for Nashville Fire Department. Contact him at firstname.lastname@example.org.
Jeremy Brywczynski,MD, is an assistant professor of emergency medicine at Vanderbilt. He serves as an assistant medical director for both Nashville Fire Department and Vanderbilt_s aeromedical LifeFlight program.
Corey Slovis,MD, FACP, FACEP, FAAEM, is professor and chair of emergency medicine at Vanderbilt University Medical Center and serves as the medical director for Nashville Fire Department and Nashville International Airport. Slovis is also a member of the JEMS editorial board. Contact him email@example.com.
Learn more from Dr. Slovis at the EMS Today Conference & Expo, March 2Ï6 in Baltimore.
For more on asthma exacerbation:jems.com/wesley