A local nebuliser guidance document has been designed with the aim of providing a framework for standardised prescribing and administration of nebulised therapies
Sarah Denman PGDipPharmP
Advanced Clinical Pharmacist for Adult Cystic Fibrosis and Immunology
Toby Capstick MRPharmS DipClinPharm
Lead Pharmacist for Respiratory Medicine
The Leeds Teaching Hospitals NHS Trust, Leeds, UK
A variety of drugs can be used to treat conditions and diseases of the respiratory tract and these can be given intravenously, orally, or can be inhaled. Such conditions include the treatment of bronchospasm with bronchodilators, airway inflammation with corticosteroids, and diseases such as mycobacterial infections with aminoglycosides and pseudomonal infections with aminoglycoside or polymyxin antibiotics.
Systemic routes of administration usually require the use of larger doses that could result in systemic adverse effects owing to their action elsewhere in the body. Consequently, it can be advantageous for certain drugs to be inhaled, allowing the drug to be targeted directly to the respiratory tract, using lower doses with a faster onset of action and less potential for systemic adverse effects. Nebulisers can be used to administer medicines directly to the respiratory tract, and they operate by allowing liquid medicines to be vapourised as air is driven through a nebuliser chamber, and which can then be inhaled. As a general rule, nebulisers should be considered in the following situations:(1,2)
Where a high dose of inhaled bronchodilator is required
Where no alternative administration method is available (for example, dornase alfa)
Where a patient may be unable to use alternative inhalation devices.
The issues with nebulised therapies
There is an increasing number of medicines available that can be administered via a nebuliser chamber, some of which are licensed for nebulised administration, and some that are used off-license using a preparation intended for administration as an intravenous injection. In the latter, there is often a lack of information provided by the manufacturer for healthcare professionals and patients about how to prescribe and administer these drugs via a nebuliser.
Furthermore, there is a wide range of available equipment for nebulising drugs, including compressors, nebuliser chambers, filters, masks and mouthpieces. It is often not appreciated that different compressors and nebulisers may have different drug delivery characteristics and administration times, resulting in significantly different lung deposition affecting the prescribed dose,1 and consequently some nebulised drugs are intended only for use with certain compressors and nebuliser systems.
For example, one million units of colistimethate sodium administered as the Promixin® brand will deliver 198,000 units over three minutes, 36 seconds to the patient via an I-neb (Philips Respironics) nebuliser system, compared with 214,000 units over seven minutes, four seconds via a Pari LC® Plus with a Pari TurboBoy® S compressor, or 182,000 units over five minutes, 18 seconds via a Philips Respironics Sidestream® with a Portaneb compressor.(3)
Additionally, different types of equipment are required to reduce or prevent adverse effects with certain classes of nebulised drug. For example, a filter attachment is required when nebulising antibiotics in order to prevent release of the drug into the atmosphere, which may increase the risk of antibiotic resistance and sensitisation of other individuals to the antibiotic.(1) Other drugs, such as corticosteroids, should only be nebulised using a mouthpiece rather than a mask to avoid deposition to the face that could cause local adverse effects.(1)
It is also important to understand that different manufacturers’ compressors may not be compatible with nebulisers manufactured by other companies. For example, a Pari LC® Plus nebuliser is not compatible with a Philips Respironics Portaneb compressor because the back pressure created by the nebuliser system may cause burnout in the compressor.
While some of the issues surrounding the use of nebulised drugs are well known by non-specialist healthcare professionals, those surrounding the use of the less common nebulised drugs may not. Studies have shown that there are frequent prescribing and administration errors with nebulised drugs, which may be caused by a lack of knowledge of healthcare professionals.(4) In Leeds, there have been recurring questions from both primary and secondary care healthcare professionals about how to prescribe and administer nebulised drugs. Typical questions include:
- What are the recommended doses for less commonly used nebulised drugs?
- What type of nebuliser equipment is required to administer different drugs?
- Can different drugs be nebulised at the same time by mixing them together in the nebuliser chamber?
Where are different nebuliser equipment obtained from for patients in hospital and at home?
The European Respiratory Society advises that local guidance on the administration of nebulised medicines can improve patient safety and the effectiveness of nebuliser use.(1) Consequently, a local nebuliser guidance document was designed with the aim of providing a framework for standardising nebuliser prescribing and administration, and to provide all healthcare professionals with the support, knowledge and evidence of good practice necessary to safely prescribe and administer nebulised therapies.
Why develop web-based guidance?
Web-based guidance allows a large audience to be able to access up-to-date information easily from most clinical settings, rather than having multiple print copies that can be difficult to remove or update when they are revised. Electronic documents allow ease of searching and can use hyperlinks to allow users to quickly locate information within the guideline.
Our guidance is available on an intranet-based system called Leeds Health Pathways, which is a web-based clinical decision support tool that links to healthcare-related information and is hosted by the NHS N3 network. Leeds Health Pathways is accessible to NHS staff in both primary and secondary care within Leeds, and is a frequently accessed resource for healthcare professionals to access local clinical guidelines. This system allows updates to be published online quickly to ensure that out-of date information is not used.
Additionally, the web-based approach allows healthcare professionals to submit any comments or queries about the guideline in order to improve and clarify future updates. One example of this was when the Philips Respironics Ventstream® nebuliser, used to administer nebulised antibiotics, was discontinued in the summer of 2012. We were able to inform staff quickly of its replacement, including details of order numbers, how and where it could be purchased, and with which compressors it was compatible.
How is the guidance structured?
The guidance is divided into several sections with hyperlinks incorporated in the contents listing, allowing users to quickly access the information they require. Specific sections include:
- Practical information
- Drug monographs
- Drug compatibility information
- Patient information leaflets.
The initial sections provide general information about nebulised therapy, including how to nebulise different drugs, and the preferred compressors, nebulisers and other equipment that should be used. A pictorial glossary is included to help users understand which equipment is used, to clarify terms and ensure that practice is consistent across primary and secondary care, and ordering information to instruct where, and how, to obtain the equipment required.
Different drugs require different methods of administration, including reconstitution or dilution of the drug, as well as different nebuliser chambers and compressors. Individual referenced drug monographs (brand specific where appropriate) have been written to provide detailed information, such as:
- Mode of action
- Available strengths
- Administration information, for example, type of compressor/nebuliser chamber required, whether a filter is needed, and air/oxygen flow rate
- Monitoring required
- Any other important information
- Links to the manufacturer’s Summary of Product Characteristics and local formulary documents.
Drug compatibility information
If patients are prescribed more than one nebulised drug, there are a number of advantages to mixing two drug solutions in nebuliser chambers, including:
1. The time spent nebulising mixed drugs is shorter than when nebulising drugs are given consecutively
2. This allows a greater dose to be delivered due to the fact that the residual volume (the volume of drug solution that cannot be nebulised) is a combination of two drugs rather than just one drug. As the residual volume is a fixed volume, this means that a smaller proportion of each of two drugs is not nebulised when mixtures are used than when nebulised individually.
Although mixing different combinations of nebulised drug is common practice, there is a lack of both chemical and physical stability data for mixing different nebulised medicines. Therefore, our web-based guideline incorporates a comprehensive, evidence-based, referenced compatibility table indicating which drugs can be mixed prior to nebulisation.
John has a 20-year history of non-cystic fibrosis bronchiectasis associated with past treatment for tuberculosis. His symptoms are characterised by dyspnoea and recurrent chest infections associated with expectoration of large volumes of purulent sputum. His lungs have been colonised with a mucoid strain of Pseudomonas aeruginosa, requiring daily chest physiotherapy, nebulised bronchodilators (salbutamol 2.5mg four times daily and ipratropium 500 micrograms four times daily), sodium chloride 0.9% 2.5ml four times a day as a mucolytic to aid expectoration and colistimethate sodium (Colomycin®) two million units twice a day (reconstituted with 2ml water for injection and 2ml sodium chloride 0.9%) as a long-term antibiotic. John complains to the pharmacist that taking all his nebulised drugs is very time consuming, and so he does not always use all his nebulisers every day. On questioning, he has been nebulising each drug in succession, creating a lengthy process of four nebulisation episodes four times a day, and this is affecting his adherence and, consequently, may negatively affect his quality of life.
The pharmacist accessed the web-based nebuliser guidelines to determine whether this could be simplified. The guideline provided information about the reconstitution of colistimethate sodium and about which drugs were compatible to be mixed together and nebulised at the same time. The following simplified treatment regimen was advised:
- Colistimethate sodium (Colomycin®) two million units twice a day, reconstituted with salbutamol 2.5mg (given in the morning and at night)
- Ipratropium 500 micrograms mixed with sodium chloride 0.9% 2.5ml four times a day
- Salbutamol 2.5mg twice a day (given at lunchtime and teatime).
This regimen allowed two, rather than four, different nebulisation episodes to be undertaken four times a day. Although this is still a time-consuming process, the time spent nebulising drugs is significantly reduced, and more efficient, as a greater percentage of each drug will be administered when mixing nebuliser solutions.
Patient information leaflets
The majority of nebulised medications have patient information leaflets within their packaging; however, some medications are not licensed for nebulised administration, such as amikacin, where the intravenous preparation is administered via a nebuliser for the treatment of patients who have Mycobacterium abscessus colonised within the lungs. Our guideline incorporates specific patient information leaflets for different nebulised drugs where no manufacturer patient information leaflet exists. These can be given to patients when they are educated on their new treatment and on discharge from hospital.
In addition to drug-specific leaflets, there is also a general patient information leaflet on the use of nebulisers, including information on the care of equipment, contact numbers for obtaining new nebuliser equipment (for example, nebuliser chambers, tubing, masks or mouthpieces) and servicing requirements of the compressors provided by healthcare facilities. Our medical physics department, which supplies compressors and nebuliser equipment to patients in primary and secondary care, also provides this leaflet.
The guidance was launched in April 2011, and the electronic format allowed a simple review and update in July 2012. It has received excellent feedback from a broad spectrum of users, and to date there has been no negative feedback. The guideline is used widely and logs record that it has been accessed 1200 times, with an average of 50 views per month across primary and secondary care.
- Administering a medication via the nebulised route allows the drug to be targeted directly to the respiratory tract, using lower doses with a faster onset of action and less potential for systemic adverse effects.
- There is a large number of medications (both licensed and unlicensed) that can be administered by a range of different nebuliser equipment, each with different characteristics and compatibilities. This can be very confusing for healthcare professionals, especially with medications that are nebulised less frequently.
- The nebuliser guidance aims to provide a framework for standardising nebuliser prescribing and administration, and to provide all healthcare professionals with the support, knowledge and evidence of good practice necessary to safely prescribe and administer nebulised therapies.
- Web-based guidance allows a large audience to be able to access up-to-date information easily from most clinical settings.
- Included within the guidance was practical information on administration, individual drug monographs, drug compatibility information and patient information leaflets.
- Boe J et al. European Respiratory Society guidelines on the use of nebulizers. Eur Respir J 2001;18:228-42.
- Kelly C, Lynes D. Best practice in the provision of nebuliser therapy. Nurs Stand 2011;25:50-6.
- Electronic Medicines Compendium. Datapharm Communications Ltd. Promixin 1 million International Units (IU) powder for nebuliser solution. Profile Pharma Ltd. http://emc.medicines.org.uk (accessed 24 May 2013; date of last text revision 20 June 2011).
- Khoo SM, Lim TK. Prescribing and administration of nebulised bronchodilators: a prospective audit in a university hospital. Respirology 2003;8:205-7.