Related Experiment Videos
Infection risks associated with spirometry
D R Rutala1, W A Rutala, D J Weber
1Department of Hospital Epidemiology, University of North Carolina Hospitals, Chapel Hill.
Objectives:
Spirometry is a widely used pulmonary function test that allows measurement of forced vital capacity and time-related measures of dynamic pulmonary function. This study was designed to identify the risk of cross-transmission associated with two commonly used dryrolling seal spirometers.
Design:
Using a prospective study design, we examined whether microbial contamination of spirometers occurred following use by patients with a heavily colonized or infected respiratory tract. Prior to spirometry evaluation, a patient's sputum culture and equipment samples (i.e., mouthpiece, proximal tubing, piston surface) were obtained. After patient evaluation, a sterile 2 L ventilation bag and sterile tubing were used to simulate the risk of infection of subsequent patients. Simulation 1 was performed immediately after patient testing and Simulation 2, representing a second patient was conducted approximately 18 hours later.
Setting:
This study was conducted at the University of North Carolina Hospitals, a large university teaching facility.
Patients:
Fourteen patients with underlying pulmonary disease were studied.
Results:
Our study revealed that the mouthpieces became contaminated with the patients' oral flora and with the associated respiratory pathogen. Fourteen percent of the associated tubing after patient testing contained the respiratory pathogen. All other equipment samples (e.g., interior surfaces of the machine, Simulation 1, Simulation 2 samples) were negative for the respiratory pathogen.
Conclusions:
These data suggest that mouthpieces and spirometry tubing may become contaminated with microorganisms and should not be shared between patients. Since there is little or no bacterial contamination of the surfaces inside the spirometers and cross transmission is unlikely, it is unnecessary to routinely clean the interior surfaces of the spirometers.
Insights
Spirometry mouthpieces and tubing can become contaminated with respiratory pathogens. To prevent cross-transmission, these components should not be shared between patients. Cleaning the internal spirometer surfaces is unnecessary.
Area of Science:
- Pulmonary Medicine
- Infectious Disease Control
- Medical Device Safety
Background:
- Spirometry is a crucial pulmonary function test.
- Assessing cross-transmission risk from spirometers is vital for patient safety.
- Dry-rolling seal spirometers are commonly used in clinical settings.
Purpose of the Study:
- To evaluate microbial contamination of spirometers after patient use.
- To identify the risk of cross-transmission of respiratory pathogens via spirometers.
- To inform best practices for spirometer hygiene and reprocessing.
Main Methods:
- Prospective study design involving 14 patients with pulmonary disease.
- Sputum and equipment samples (mouthpiece, tubing, piston) collected pre-spirometry.
- Simulations performed post-patient testing to assess potential for cross-transmission.
Main Results:
- Mouthpieces showed contamination with oral flora and respiratory pathogens.
- 14% of associated tubing samples tested positive for respiratory pathogens.
- Internal spirometer surfaces and simulated patient samples remained negative for pathogens.
Conclusions:
- Spirometry mouthpieces and tubing pose a risk for microbial contamination.
- Sharing of spirometry mouthpieces and tubing between patients should be avoided.
- Routine cleaning of internal spirometer surfaces is not indicated due to low contamination risk.