Switching from CFC to HFA Inhalers: What NPs and Their Patients Need to Know

Abstract

The aim of this article is to provide nurse practitioners with a better understanding of the transition from chlorofluorocarbon (CFC) to hydrofluoralkane (HFA) metered-dose inhalers (MDIs). The authors discuss the differences in these products’ propellants; the proper use, cost, and efficacy of the HFA inhalers; and the implications of the switch for NPs and for their patients with asthma.

Asthma, the most prevalent chronic illness in childhood, affects 9 million US children <17 years old.¹ Approximately 19% of all US high school students have been diagnosed with asthma.² Asthma is responsible for 14 million lost school days and $14 billion in healthcare costs and lost-productivity costs.² With the 2008 US Food and Drug Administration (FDA) mandate banning all generic CFC-containing MDIs, which are less expensive than HFA-propelled MDIs, the cost of treating asthma is expected to rise.³ Without proper clinician education and dissemination of information, misuse and confusion about the new HFA inhalers will also increase. All MDI prescribers should understand the transition and provide the most useful and up-to-date information for their patients.

For the past 50 years, CFC has been used in pressurized MDIs to force asthma medication out of the canister and into a patient’s airway.^3,4 CFC, composed of chlorine, fluorine, and carbon, has been widely used in the pharmaceutical industry for decades because of its stability, non-flammability, and low toxicity.⁵ Although CFC works well, it is one of many chemicals that deplete the ozone layer of the atmosphere. The phase-out of CFC-propelled inhalers is the result of the Clean Air Act and an international environmental treaty, the Montreal Protocol on Substances that Deplete the Ozone Layer.⁶.⁷ Under this treaty, the United States has agreed to phase out production and importation of ozone-depleting substances, including CFC. The phase-out of CFC-containing products began in January 1993 and will end in January 2010.⁷

On a routine asthma visit, 13-year-old Ashley tells the nurse practitioner that she doesn’t like her new asthma inhaler and doesn’t think that it is working. Ashley states that she needs to use her new pump 4 or 5 times because she can’t feel the medication going in. Although Ashley knew that she was getting a new inhaler, she didn’t know why and wasn’t sure how to use it. Many patients face this same situation with the switch from CFC to HFA inhalers.

HFA MDI Characteristics and Types

In response to the CFC ban, pharmaceutical companies formulated an alternative propellant for use in albuterol MDIs. CFC is being replaced by HFA, an environmentally safe propellant. Several studies have shown that HFA MDIs deliver albuterol and other medications more effectively into the lung tissue than do CFC MDIs.^8–10 Each HFA inhalation device generates its drug aerosol differently; therefore, particle size, respirable dose, lung deposition, and distribution differ.⁸

Leach and colleagues used gamma camera imaging to study lung deposition of HFA beclo-methasone.⁹ Use of HFA beclomethasone resulted in ~60% of the medication being deposited to and distributed within the lung and the central, intermediate, and peripheral airways. By contrast, the use of CFC beclomethasone resulted in only 5% lung deposition, with little penetration in the peripheral airways. With proper HFA inhaler use, less medication is deposited in the oropharynx and more is deposited in the airway and the lungs.

NPs will need to educate patients using HFA inhalers regarding the correct administration technique, use of the device with an aerochamber-type spacer, and the proper cleaning procedure. Table 1 summarizes manufacturers’ instructions regarding the use and care of these products,¹¹ which vary in terms of priming and frequency of washing.

TABLE 1.

HYDROFLUORALKANE METERED-DOSE INHALERS¹¹

HFA Bronchodilators	Active Ingredient	Maximum Number of Sprays	Dose Counter	Shake Inhaler Before Each Use?	Priming Instructions	Frequency of Washing
ProAir HFA (Teva Specialty Pharmaceuticals; www.proairhfa.com)	Racemic albuterol 90 mg per dose	200	No	Yes	Before first use, 3 sprays; after 2 weeks of non-use, 3 sprays	Wash plastic actuator weekly with water; air dry
Proventil HFA (Schering Corporation; www.proventil.com)	Racemic albuterol 90 mg per dose	200	No	Yes	Before first use, 4 sprays; after 2 weeks of non-use, 4 sprays	Wash plastic actuator weekly with water; air dry
Ventolin HFA (GlaxoSmithKline; www.ventolin.com)	Racemic albuterol 90 mg per dose	200 (or replace 6 months after opening)	Yes	Yes	Before first use, 4 sprays; after 3 days of non-use, 4 sprays	Wash plastic actuator weekly with water; air dry
Xopenex HFA (Sepracor Inc.; www.xopenex.com)	Levalbuterol 45 mcg per dose	200	No	Yes	Before first use, 4 sprays; after 2 weeks of non-use, 4 sprays; if MDI is dropped, 1 spray; after washing, 1 spray	Wash plastic actuator weekly with water; air dry and prime once

Reprinted with permission from Allergy & Asthma Network Mothers of Asthmatics (www.aanma.org).

When an HFA MDI is used with a spacer, 75% of the medication delivered reaches the lungs because the particles are less likely to attach to the spacer walls.¹⁰ An evaluation of valved holding chambers (VHCs) used to deliver albuterol with an HFA propellant demonstrated that the VHC-type spacer did not change the dose delivered to the lungs—as determined by fine particle mass content and an Andersen cascade stack—compared with the dose delivered without the VHC.¹² Use of a static-free aerochamber with an MDI is recommended. Tests comparing HFA-and CFC-based aerosols have shown that HFA-based delivery of medications such as albuterol is as good as or better than that achieved with CFC-based inhalers.⁸

Although the international CFC ban was passed in 1987, replacement of CFC with HFA has occurred only recently in the United States. On May 30, 2008, the FDA issued a public health advisory indicating that patients using CFC MDIs needed to switch to HFA-propelled inhalers by December 31, 2008.³ Only four rescue medications serve in place of CFC albuterol: three of these products are albuterol-containing inhalers (ProAir HFA Inhalation Aerosol, Proventil HFA Inhalation Aerosol, and Ventolin HFA Inhalation Aerosol) and one of these products is a levalbuterol-containing inhaler (Xopenex HFA Inhalation Aerosol).

Inhaler Technique

Noteworthy to clinical practice is how the transition to HFA inhalers will affect medication use and adverse reactions. Several studies have assessed patients’ inhalator technique.^13–15 Most patients believe that they perform the technique correctly, but studies that have assessed performance of essential and non-essential steps of the process do not support this belief.^13–15 Instead, studies have shown that only 58%–78% of participants carried out all essential steps correctly.^13–15 Factors contributing to poor inhalation technique include (1) lack of practitioner education and ability to perform and teach the appropriate technique, (2) lack of practitioner time to educate patients regarding proper use of the inhaler, (3) patients’ lack of understanding about the reason for the medication, and (4) practitioners’ failure to routinely assess patients’ inhaler technique.¹⁶ Furthermore, MDIs are frequently used during periods of an acute asthma exacerbation, a situation that increases anxiety, which may complicate the coordination of breath and actuation of the medication, as well as the ability to hold one’s breath for the 5–10 seconds required by most inhalers.

Specific aspects of an HFA MDI may inhibit successful inhaler technique. For example, some patients do not think that they received the medication because the force of the delivery is less than that of their previously used CFC MDI.¹⁶ This perception may lead to unnecessary additional actuation of the medication, potentially increasing the amount deposited in the lungs and absorbed systemically, which could lead to adverse effects. In addition, frequent actuation of the device decreases the amount of medication available, which may lead to decreased time between medication refills, thereby exacerbating the increased cost associated with HFA MDI use. Ramifications of misuse—pumping greater than the recommended 2–4 puffs every 4–6 hours—will lead to more turnovers in MDIs. This misuse further supports the need for practitioner and patient education in all facets of asthma management. Also, insurance companies will deny refills too soon when improperly dosed, leaving patients without an inhaler.

Cost

The switch from CFC to HFA inhalers is beneficial from an environmental standpoint, but it does have financial ramifications. CFC albuterol inhalers were among the most trusted, readily available, and cost-effective medications on the market for >50 years. Generic CFC albuterol cost $13–$17 for one MDI. Table 2 lists the cost of various HFA inhalers as of October 2009. Prices may vary according to health insurance prescription plans.

TABLE 2.

MDI INHALER PRICES

Medication	Cost as of 10/09
ProAir HFA	$41.84/inhaler
Ventolin HFA	$37.99/inhaler
Proventil HFA	$52.02/inhaler
Xopenex HFA	$53.84/inhaler

Available at: www.drugstore.com

No FDA-approved generic albuterol or levalbuterol HFA MDIs are available. Until the HFA MDI patents expire, the cost of HFA quick-relief asthma inhalers will be higher than that of previous inhalers. The added cost of the HFA inhaler affects all concerned parties, including patients, insurers, and government health programs. The higher cost may be a hardship for many families, who must be given ample time to seek and apply for assistance from government-supplied programs or pharmaceutical patient assistance programs. Patients in need of financial aid may access The Partnership for Prescription Assistance by calling 1-888-477-2669 or visiting www.pparx.org.¹⁷

Asthma Control

Although the aim of this article is to inform NPs about the practical differences between CFC and HFA rescue inhalers, this information needs to be placed within the context of the most recent guidelines for the diagnosis and management of asthma. The Expert Panel Report 3: Guidelines on Asthma (EPR-3), commissioned by the National Asthma Education and Prevention Program and coordinated by the National Heart, Lung, and Blood Institute, released the most recent practice guidelines in 2007.¹⁸ Controlling asthma is still done via the stepwise approach, with short-acting beta-2 agonists (SABAs) such as albuterol or levalbuterol used for quick relief of symptoms.¹⁸ Table 3 summarizes the assessment, diagnosis, and treatment of patients with asthma in an office setting.¹⁹

TABLE 3.

ASSESSMENT, DIAGNOSIS, AND TREATMENT OF PATIENTS WITH ASTHMA IN AN OFFICE SETTING¹⁹

Assess severity and control	Prescribe rescue medication. Prescribe an inhaled corticosteroid for at least 4–6 weeks if warranted by patient symptoms.
▪ Current impairment
▪ Future risk
Address	Teach spacer device technique. HFA inhalers require static-free spacer.
▪ Inflammation
▪ Bronchoconstriction
Differentiate	Set up follow-up appointment in 4–6 weeks: step-up/step-down and modify asthma action plan.
▪ Controller medication
▪ Rescue medication
Write an Asthma Action Plan	Prescribe additional albuterol and spacer for school. Annual influenza vaccine, regardless of severity.
▪ Daily management and recognizing signs and symptoms of worsening
▪ Step-up “Yellow Zone” plan for home management

Essential Information from the 2007 NHLBI Guidelines for the Diagnosis and Treatment of Asthma Expert Panel 3 Report. Available at: http://www.getasthmahelp.org/Trifold_essentialinformation_85x11final.pdf. With special thanks to the Asthma Initiative of Michigan (http://www.getasthmahelp.org/).

Levels of asthma severity are divided into two main categories, intermittent and persistent. Within the persistent category, classifications of mild, moderate, and severe are determined based on symptoms. As with previous recommendations, treatment varies according to age and level of asthma severity. To manage asthma, NPs should assess daily symptoms, nocturnal symptoms, use of rescue medication, limitations in activity, and patient concerns.¹⁸

The EPR 3 emphasizes the need to assess patients’ level of impairment and risk for future exacerbations,¹⁸ which is best accomplished by asking them about asthma exacerbations, timing, triggers, and co-morbidities. To promote addressing asthma control at each visit, additional resources are available for quick reference in the clinical setting. A convenient reference tri-fold containing essential information for practitioners is found at http://www.getasthmahelp.org/EPR3AsthmaGuidelines.asp.¹⁹ Follow-up visits are critical when attempting to gain control. During this time, patients are monitored every 4–6 weeks. Once control is achieved, the EPR 3 panel suggests re-evaluation every 3–6 months.¹⁸

Implications for Practice

The best way in which NPs can serve their patients with asthma is to provide them with information about the disease and emphasize the importance of asthma control. Patients and their families must learn how to prevent acute exacerbations, how to recognize signs and symptoms of an exacerbation, and how to administer prescribed medications properly. NPs must spend additional time when beginning the transition from the CFC MDI to the HFA MDI to ensure that patients and family members understand the differences between the medication delivery devices. Patient education in the correct use of the device is essential to maximize therapeutic benefit.²⁰ The two main differences that patients and families need to be aware of are that (1) HFA-propelled systems deliver a softer spray and (2) the taste of the drug will be altered.²⁰ If patients say, “The medication isn’t working. I can’t feel it,” NPs must take time to validate their level of comprehension and review the medications and how to administer them correctly. Clinician education regarding the transition from CFC MDIs to HFA MDIs should also include school nurses because of their pivotal role with student health.

Because of the increased cost associated with the transition to HFA MDIs, many patients and families will question the need for the change, which could further increase noncompliance. Therefore, NPs must spend time educating interested parties with regard to the rationale behind the mandated inhaler change. The Internet is full of chat rooms and message boards that demean the efficacy of HFA MDIs, and a national petition to save CFC MDIs is gaining support.²¹ To counter this misinformation, the FDA and other asthma associations are disseminating useful information for patients. NPs need to help patients learn about reliable and trustworthy resources to facilitate the change. Four of these resources are listed here:

• Environmental Protection Agency: http://www.epa.gov/asthma/resources.html

• National Association of School Nurses: http://www.nasn.org/Default.aspx?tabid=144

• Allergy and Asthma Network, Mothers of Asthmatics: http://www.aanma.org/

• Kids Health (Nemours): http://kidshealth.org

Conclusion

Asthma is a chronic illness that requires multifactorial self-care measures to properly control the disease and prevent acute exacerbations, emergency department visits, hospitalizations, and asthma-associated deaths. Although often faced with a decrease in available time with patients and their families, NPs must take the time to thoroughly educate and assess patient/family knowledge of self-care measures and performance of proper inhalation techniques to optimize the benefit of inhaled medications.

One of the primary asthma self-care measures is the use of inhalers that deliver medication to the lungs to maintain their function and prevent or treat acute exacerbations. In the past, MDIs contained CFC to assist with propelling the medication from the canister to the lungs. However, because of scientific evidence showing the adverse effect of CFCs on the Earth’s atmosphere, use of CFC MDIs has been banned and patients must transition to new inhalation devices that use HFA as the medication propellant, which does not harm Earth’s ozone layer.

Although the FDA mandated the phasing out of CFC-propelled inhalation devices by 2008, this information has not sufficiently reached clinicians or the public. Lack of communication related to the phasing out of a widely used asthma treatment medication could lead to widespread concern and confusion. Informed NPs taking the lead in educating patients and the community can decrease inhaler misuse. Improving communication regarding the use of asthma medications will improve asthma outcomes.