Circulaire II Hybrid is Westmed’s solution to providing high-efficiency aerosol drug delivery in the home care environment. This is especially important when patients are discharged and scripted for a nebulizer and air compressor for home use.  Many times, the nebulizer and compressor combinations supplied by home care companies do not meet the same standards and performance as the aerosol therapy administered in the hospital using 50 psig piped gases and calibrated medical flowmeters. Consequently, it is possible that many home care patients receive poor aerosol treatments that may be one of the factors that contributes to untimely readmission.

When it comes to reducing untimely readmissions of chronic asthma and COPD patients, why take chances?  

Like the Circulaire II, the Circulaire II Hybrid uses the conserver principle to prevent aerosol drug waste and increase the amount of drug inhaled on each breath.  However, the Hybrid utilizes an elastomeric reservoir ball that is easily detached for cleaning, along with the other parts of the system, making it perfect for use in the home.  The Hybrid is also recommended for use in the hospital when “sticky” medications such as Mucomyst or Tobi are used because, unlike the thin-film reservoir bag supplied with the Circulaire II, the elastomeric reservoir ball of the Hybrid is easily removed for rinsing along with the nebulizer at the conclusion of each treatment.

Superior aerosol delivery. The Hybrid’s reservoir is like a “holding chamber for a nebulizer,” and ensures superior aerosol delivery, even at home, by instantly compensating for the low output pressure commonly found with home nebulizer compressors.1

Figure (above). Example of Inhaled Mass of aerosolized albuterol delivered at 3 minutes and 6 minutes of treatment time with the Pari Vios air compressor and 8 different nebulizers. The Circulaire II Hybrid is color-coded dark purple.  All nebulizers were charged with 3 mL of 0.083% albuterol (2.5 mg/3 mL). Inhaled mass for Circulaire II Hybrid was 0.733 mg.  See the Gardenhire Study PowerPoint Slide Set for the complete study and results for other air compressors.

Protect the patient. Protect the caregiver.

In addition to being a holding chamber that enhances aerosol delivery, the reservoir also prevents room air dilution of aerosol to achieve the highest Fraction of Inhalable Aerosol (FIA) in the industry. In fact, multiple studies confirm, the Circulaire System delivers more drug mass in less time than any other conventional nebulizer.

Distinctive by design, the Hybrid system’s unique safety features include an integral expiratory filter that protects the caregiver from inhaling patient medications, as well as droplets that may be exhaled or coughed out. Plus, the system’s internal one-way “flapper” valve virtually eliminates the risk of the patient re-breathing into the nebulizer, to protect both the nebulizer and the reservoir from contamination by exhaled organisms.

As an added therapy advantage, a simple setting of the Hybrid system’s unique Variable Expiratory Resistor enables the user to administer Positive Expiratory Pressure (PEP) during drug delivery. An optional Pressure Manometer plus adult and pediatric Non-vented Masks are also available. 


Download the Circulaire II Hybrid Brochure



1. Gardenhire, “Circulaire II Hybrid with 6 Different Air Compressors” (Abstract for AARC Open Forum 2013). Optimal function of an SVN is dependent on proper driving pressure and flow, which apparently cannot be uniformly achieved by some air compressor and nebulizer combinations. The conserving effect of the Circulaire II Hybrid appears to compensate for marginally performing home air compressors and outperforms other SVNs tested. The Circulaire II Hybrid delivered from 1.6 to 2.8 times more medication than other nebulizers operated with the same air compressors, which was statistically significant.
⬇︎ Download, PDF, 164 Kb.

2. Grzeskowiak, “Evaluation of the Circulaire II Aerosol Drug Delivery System for Microbiological Contamination” (Abstract for AARC Open Forum 2013). Abstract of a clinical study, submitted to AARC 2013 Open Forum, in which Circulaire II and Circulaire II Hybrid nebulizers and reservoirs were cultured daily for up to 4 consecutive days while in use. The study concluded that, despite using minimal post-treatment practices, in 252 cultures, no significant organism growth was found in either the nebulizer or reservoir of the Circulaire II devices. These findings suggest that the valved conserver device may isolate the nebulizer and reservoir and protect them from contamination.
⬇︎ Download, PDF, 77 Kb.

Additional Reading:

“Understanding the Hess Paper.” This Westmed Clinical Education Bulletin dissects the classic Hess and colleagues paper wherein they compare functional performance of 17 different small volume nebulizers and determine that the Westmed VixOne is a top performer.
⬇︎ Download, PDF, 5 Mb.

Gardenhire, “An In Vitro Comparison of Dosimetric and Constant Output Nebulizers VixOne versus AeroEclipse” (Respir Care 2007). This bench study documents that the VixOne nebulizer outperforms the AeroEclipse II nebulizer in both continuous mode and breath-actuated mode with respect to inhaled mass, and shows that there is no statistically significant different between the two devices.
⬇︎ Download, PDF, 102 Kb.

Dennis, Test Report, “Circulaire II vs AeroEclipse II BAN” (SolAeroMed 2009).  This bench study using the European Nebulizer Standards methodology demonstrates greater aerosol output and shorter delivery times for the VixOne nebulizer when compared to the AeroEclipse nebulizer at two different breathing patterns.
⬇︎ Download, PDF 435 Kb.

McPeck, “In Vitro Inhaled Aerosol Comparison of a Conserver Nebulizer (Circulaire II) vs a Breath-Actuated nebulizer (AeroEclipse II)” (Respir Care 2010). This bench study demonstrated that the Circulaire II outperforms the AeroEclipse II with respect to greater Inhaled Mass and shorter treatment times measured during 4 different breathing patterns.
⬇︎ Download, PDF, 817 Kb.

McPeck, “Financial Impact Spreadsheet AARC” (Respir Care 2010). This spreadsheet analysis demonstrates how the treatment time savings of the Circulaire II can be applied on a larger scale to achieve significant department time savings during different treatment scenarios and against other common nebulizers.
⬇︎ Download, PDF, 1.8 Mb.

Gardenhire, “In Vitro Comparison of Dosimetric Nebulizers” (Am J Respir Crit Care Med 2011). This bench study demonstrates that the Circulaire II outperforms the AeroEclipse II and delivers 53% more medication over a 5 minute treatment. These results were statistically significant.
⬇︎ Download, PDF, 408 Kb.

Gardenhire, “Circulaire II Hybrid with 6 Different Air Compressors” (Poster at North American Cystic Fibrosis Conference, 2013).
⬇︎ Download, PDF, 1.7 Mb.

Grzeskowiak, “Evaluation of the Circulaire II Aerosol Drug Delivery System for Microbiological Contamination” (Poster at AARC Open Forum 2013).
⬇︎ Download, PDF, 2.9 Mb.

“Protect the Patient; Protect the Caregiver with Circulaire.”  This Westmed Clinical Education Bulletin reminds practitioners of the risks of aerosol therapy and discusses a recent study that proved that the Circulaire II system, with its unique “flapper valve” actually protects the nebulizer and the aerosol reservoir from becoming contaminated by exhaled patient droplets contained microorganisms. In addition, the CEB also discusses the importance of the integral exhalation filter in preventing exposure of healthcare workers to inhalable airborne medication particles and exhaled patient droplets that could cause illness, infection or untoward medication reactions.
⬇︎ Download, PDF, 358 Kb.

Grzeskowiak, “Adding Value to Aerosol Therapy.”  (RT Magazine, March 2014).
⬇︎ Download, PDF, 2.4 Mb.