COPD & Breath Alcohol Testing
Counterpoint Journal, Volume 2; Issue 1 - Article 1 (April 2017)
Jan Semenoff, BA, EMA
Forensic Criminalist
Here is a quick take-away from this article:
- COPD is a blanket term for a group of progressive lung diseases affecting about 10% of the population.
- COPD's damage to the lungs is assessed by a simple lung function test.
- One of the lung function tests is called an FEV1 test.
- Numerous studies have concluded that a person with an FEV1 of about 1.5 - 2.3L or lower will be unable to provide a breath sample into a breath alcohol testing device.
- The person with a history of severe COPD may be able to blow long enough, but not hard enough, or vice versa, and therefore be unable to complete the breath test.
- Any "refusal" charge generated by a person with COPD warrants further investigation.
- There is no evidence to suggest that a person with COPD will deliver a falsely-inflated breath test result due to their condition.
- Practice tips are included at the end of the article.
What is COPD?
COPD - Chronic Obstructive Pulmonary Disorder
COPD is a blanket term used to describe various progressive lung diseases, including asthma, chronic bronchitis and emphysema.
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What is COPD?
Chronic Obstructive Pulmonary Disease (COPD) is an umbrella term used to describe progressive lung diseases including:
COPD is one of the most common lung disorders in adults world-wide and causes of death. COPD affects an estimated 30 million individuals in the U.S., and over half of them have symptoms of COPD but are unaware they have the condition. Early screening can identify COPD before major loss of lung function occurs. |
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COPD is characterized by limitations in air-flow
Air flow limitation can be caused by asthma, chronic bronchitis, or emphysema owing to inflammation and excess mucus that decreases airflow. Those suffering from COPD have reduced forced expiratory volumes and might be unable to satisfy the breath-sampling requirements with some breath-alcohol analyzers. (See below). COPD ranks as one of the leading causes of death in developed nations in both men and women and smoking is one of the primary causes. |
Figure 1 - The effect of asthma on the bronchiole (part of the airway in the lungs). During an asthma attack, the bronchioles swell, and can fill with mucus, making breathing very difficult.
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Figure 2 - Occupational exposure to fumes, dust, chemical vapours and smoke are one of the leading causes
of COPD.
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In 80-90% of cases, COPD is caused by smoking
Other causes of COPD can include:
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COPD develops over time.
In most cases, COPD is diagnosed in people over 40 years of age. Someone with COPD may not realize that they are becoming more short of breath until it becomes very hard to do simple tasks like walking up stairs. When you have COPD, your lungs are obstructed or blocked, making it hard to breathe.
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Figure 3 - A comparison of healthy alveolar sacs compared to those with COPD.
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Signs and symptoms of COPD
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COPD patients display the following signs (external observable issues) and symptoms (chief complaint of the patient):
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Patient assessment and diagnosis can be carried out in a doctor's office using a simple spirometer test.
Measuring COPD
FEV, VC, and FVCs
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Measuring Disability:
To measure the disability experienced by COPD patients, we need to look at the testing done to determine the degree of lung function impairment. Respiratory specialists measure lung function, among other ways, assessing three key parameters: FEV, VC, and FVC. These are all specific lung function assessments that are measured during spirometry tests. The measurements are performed during forceful exhalation. |
A modern Spirometer, used to assess a patient's COPD.
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FEV - Forced Expiratory Volume
Forced Expiratory Volume (FEV) measures the volume of air a person can exhale during a forced breath.
VC - Vital Capacity
Vital capacity (VC) is the maximum amount of air a person can exhale from the lungs after a completely full inhalation.
FVC - Forced Vital Capacity
Forced Vital Capacity (FVC) is the total volume of air exhaled during the FEV test.
Forced Expiratory Volume (FEV) measures the volume of air a person can exhale during a forced breath.
- The amount of air forcefully exhaled during the first (FEV1), second (FEV2), and/or third seconds (FEV3) of the forced breath.
- A person with asthma or COPD will have a lower FEV1 test compared to a healthy person.
VC - Vital Capacity
Vital capacity (VC) is the maximum amount of air a person can exhale from the lungs after a completely full inhalation.
FVC - Forced Vital Capacity
Forced Vital Capacity (FVC) is the total volume of air exhaled during the FEV test.
- In general, it is common in healthy individuals to be able to expel 75% - 80 % of their vital capacity in the first second of the FVC test.
- Establishing a “normal” FVC is not as simple as it seems, as it combines age, gender, predicted values, allowances for history of smoking, etc. In simple terms, a “normal” person will have a FVC between 3-5 litres, as a rule of thumb.
COPD's impact on breath alcohol testing
There is no evidence to suggest that a person who suffers from COPD will provide falsely-inflated BrAC results due to their condition. Simply put, having COPD (Chronic Bronchitis, Emphysema or Asthma) doesn't make your breath results higher than your blood alcohol content. In fairness - it hasn't been studied. However, what has been studied is the ability of persons with COPD to provide a breath sample suitable for analysis in a breath alcohol testing device. We aren't so concerned about the BrAC number generated, but in their ability to physically provide a sample.
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Breath Test Requirements
Breath test devices are designed to obtain a sample of deep lung air, analyze it for alcohol, and express the concentration of alcohol in a given unit of measure. Most modern units operate on the principle that a person, regardless of their physical state, must exhale with sufficient force to activate a pressure sensor or transducer of some sort. This action in turn activates a timing circuit. |
The test subject must maintain an even exhalation with sufficient force to maintain the minimum pressure set for the pressure transducer. As long as this minimum pressure is maintained, the timing circuit continues, and the sample will then be received, and subsequently analyzed, at the end of expiration. Specific parameters for time, pressure and volume are required to obtain a sample that can be analyzed by the instrument.
In order to achieve the desired target goal of a deep-lung air sample, the minimum requirements for most breath test instruments is set at:
- LONG ENOUGH - An exhalation of five to six seconds duration.
- HARD ENOUGH - A minimum exhalation force required is typically set at a pressure equivalent to a 15 cm (6”) column of water.
- EXHALED VOLUME - The target volume for exhalation is typically set at between 1.1 – 1.5 litres of breath.
Refusal to provide a suitable sample
The concern, of course, is the inability to provide a breath sample into a breath alcohol testing device which might result in a charge of "refusal", often considered a criminal offence in many jurisdictions. In Canada, as an example, failing to provide a suitable sample for analysis carries the same criminal consequences as driving while impaired, or with a blood alcohol level in excess of the legal limit. So, a refusal charge generated by a person with a history of COPD should be investigated further.
Keep in mind that this inability to provide a suitable sample might be the result of an actual lack of physical ability to provide the breath sample, as opposed to a wilful choice to not provide the breath sample.
The concern, of course, is the inability to provide a breath sample into a breath alcohol testing device which might result in a charge of "refusal", often considered a criminal offence in many jurisdictions. In Canada, as an example, failing to provide a suitable sample for analysis carries the same criminal consequences as driving while impaired, or with a blood alcohol level in excess of the legal limit. So, a refusal charge generated by a person with a history of COPD should be investigated further.
Keep in mind that this inability to provide a suitable sample might be the result of an actual lack of physical ability to provide the breath sample, as opposed to a wilful choice to not provide the breath sample.
Jones and Andersson reported that about 5% of women between 15-24 years of age, and about 8% of women between 25-34 years of age were unable to provide a sufficient sample into an Intoxilyzer 5000S. These were normal, healthy women. None were identified as diminutive in stature.
Odell, et al concluded in their 1998 study, Breath Testing in Patients with Respiratory Disability, that:
“Three of the five subjects had restrictive respiratory disease raising the possibility that it is the absolute lung volume rather than the respiratory flow rates which is the parameter.”
They found that, in some cases, a person with a Forced Expiratory Volume over 1 second (FEV1) greater than 1.5 and a Forced Vital capacity (FVC) greater than 1.75 was able to provide a sample. However, often the person could not complete the sampling requirements, as they ran out of exhaled breath. 45% of the patients tested could not maintain the exhalation flow sufficient to provide a sample suitable for analysis.
Odell, et al concluded in their 1998 study, Breath Testing in Patients with Respiratory Disability, that:
“Three of the five subjects had restrictive respiratory disease raising the possibility that it is the absolute lung volume rather than the respiratory flow rates which is the parameter.”
They found that, in some cases, a person with a Forced Expiratory Volume over 1 second (FEV1) greater than 1.5 and a Forced Vital capacity (FVC) greater than 1.75 was able to provide a sample. However, often the person could not complete the sampling requirements, as they ran out of exhaled breath. 45% of the patients tested could not maintain the exhalation flow sufficient to provide a sample suitable for analysis.
The Lion S-D2 handheld screening device used in the United Kingdom. The similar S-L2 was used in the Briggs study.
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A British study conducted by Briggs et al in 1990, concluded that in using the Alcolmeter, (Lion Alcolmeter S-L2) subjects with a FVC less than 1.5 litres were unlikely to be able to activate the pressure transducer. A study I participated in (Prabhu, et al; CHEST, 1991) concluded that about 75% of patients with a FVC less than 1.43 litres could do the test. Some patients with a FVC less than 1.0 litre may not be able to provide a sample. One particularly stubborn patient with a FVC of 0.75 litres was successful on his third attempt.
Remember, establishing a “normal” FVC is not as simple as it seems, as it combines age, gender, predicted values, allowances for history of smoking, etc. In simple terms, a “normal” person will have a FVC between 3-5 litres, as a rule of thumb. |
I participated in a study on the ability of people with COPD to provide a breath sample into a breath alcohol device (CHEST, 1991). We utilized the FVC values of 3-5 litres as "normal". In comparison with these FVC values, our study was conducted on severely affected patients with a long-term history of asthma or COPD. Yet, only 3/102 were unable to provide a suitable sample. Some of the patients studied, it should be noted, were during actual or artificially induced asthmatic attacks, and still able to provide samples.
We found that it was the test subject's overall lung volume (their Vital Capacity) that presented the greatest obstacle to providing a suitable sample. In short, some test subjects could blow hard enough to activate the pressure transducer, but no long enough to meet the minimum 5-second exhalation requirement. They simply ran out of breath as the Vital capacity of their lungs was too small to deliver the necessary sample (5-second, 1.1 – 1.5 litre of breath) required. It. was discovered that most persons with an FEV1 less than 1.5 and an FVC less than 1.43 was not able to provide a suitable sample under most circumstances. Less than these values, they were unable to provide a sample that the device could analyze.
We found that it was the test subject's overall lung volume (their Vital Capacity) that presented the greatest obstacle to providing a suitable sample. In short, some test subjects could blow hard enough to activate the pressure transducer, but no long enough to meet the minimum 5-second exhalation requirement. They simply ran out of breath as the Vital capacity of their lungs was too small to deliver the necessary sample (5-second, 1.1 – 1.5 litre of breath) required. It. was discovered that most persons with an FEV1 less than 1.5 and an FVC less than 1.43 was not able to provide a suitable sample under most circumstances. Less than these values, they were unable to provide a sample that the device could analyze.
Honeybourne, et al concluded that a person needed an FEV1 greater than 1.1 to provide a sample. However, they also noted than 8/9 patients with an FVC greater than 1.5 could NOT successfully provide a sample onto a police breath test device (the Intoxilyzer 6000, used in the United Kingdom.
Gomm, et al conducted two studies in 1991 and 1993 that dealt with the ability of persons with COPD or persons of very small stature to provide breath samples into police breath test devices. Both studies concluded that the test subject had to have an FEV1 greater than 2.0 – 2.3 and an FVC greater than 2.6 in order to successfully provide a breath sample.
The 1993 Gomm, et al study is also very interesting, as it is the only one to address the ability of small statured people to provide a sample. This study added an additional element – PEF, or Peak Expiratory Flow, measured in litres per minute. They concluded that the person would have to provide a PEF of at least 330 L/min to meet the sampling requirements.
The 1993 Gomm, et al study is also very interesting, as it is the only one to address the ability of small statured people to provide a sample. This study added an additional element – PEF, or Peak Expiratory Flow, measured in litres per minute. They concluded that the person would have to provide a PEF of at least 330 L/min to meet the sampling requirements.
Practice tips:
Where does this leave your client?
- This is a refuse breath test issue. All the studies here, including the CHEST study that I participated in, refer to patients with COPD to provide a measurable breath sample. None of them speak to the possibility of inflated breath test results due to a history of COPD.
- Although FEV1 and FVC are reliable measurands to assess the suitability to provide a sample, there were still some people in all the studies who had the lung functions exceeding the minimum values, who were still not able to keep the time and pressure necessary to provide a suitable sample.
- In general terms, a person with an FVC < 1.5 L has a fairly significant degree of lung function impairment. A slight history of COPD that is not dealt with by aggressive treatment will probably not preclude a person from providing a breath sample.
- When in doubt, recommend to your client that they seek medical assessment, and have a spirometry test performed.
- The ability to provide a breath sample capable of being analyzed must be assessed on a case-by-case basis, following a spirometry test. As such, "refusal" cases where the test subject has an FVC less than 2.3 litres must be considered suspect, and consideration for a valid medical reason for the refusal taken into account.
Send me your questions or comments:
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For further study:
- Briggs JE, Patel H, Butterfield K, Honeybourne D. “The Effects of Chronic Obstructive Airway Disease on the Ability to Drive and Use a Roadside Alcolmeter”, Respiratory Medicine 1990; 84:43-46.
- Hlastala, M.P. and Anderson, J.C., ”The Impact of Breathing Pattern and Lung Size on the Breath Alcohol Test”, Annals of Biomedical Engineering, Volume 35, No. 2, February 2007, pp. 264-272.
- Jones, A.W. and Andersson, L., “Variability of the Blood/Breath Alcohol ratio in Drinking Drivers”, Journal of Forensic Science, 1996; 41(6): 916-921.
- Odell, M.S., McDonald, C.F., Farrar, J, Natsis, J.S., and Pretto, J.F., “Breath Testing in Patients with Respiratory Distress”, Journal of Clinical Forensic Medicine (1998) 5, pages 45-48.
- Prabhu, M.B., Hurst, T.S., Cockcroft, D.W., Baule, C. and Semenoff, J., “Airflow Obstruction and Roadside Breath Alcohol Testing”, Chest 1991: Volume 100, pages 585-586.
- Gomm, P.J. and Broster, C.G., “Study into the Ability of Healthy People of Small Stature to Satisfy the Sampling Requirements of Breath Alcohol Testing Instruments”, Med. Sci. Law, Volume 33, No. 4, pages 311-314.
- Gomm, P.J., Osselton, M.D. and Broster, C.G., “Study into the Ability of Patients with Impaired Lung Function to Use Breath Alcohol Testing Devices”, Med. Sci. Law, Volume31, pages 221-225.
- Honeybourne, D., Moore, A.J., Butterfield, A.K. and Azzan, L., “A Study to Investigate the Ability of Subjects with Chronic Lund Disease s to Provide Evidential Breath Samples Using the Lion Intoxilyzer 6000UK Breath Alcohol Testing Device”, Respiratory Medicine (2000), Volume 94, pages 684-688.
