For Commercial Drivers With asthma: is a pulmonary function test required to check FEV1 ?

It is the medical examiner’s discretion as to whether or not to order pulmonary function testing in an asthmatic, depending on the degree of symptoms and control, but yes, generally you would order a pulmonary function test to check FEV1.

Is it mandatory or recommended to perform pulmonary functions tests on all smokers over the age of 35?

This is a guideline recommendation, not a requirement.  The rationale is that pulmonary function begins to deteriorate long before significant symptoms of COPD develop.  If you choose not to order PFTs on smokers over 35, you should document why you are not following guidelines in the comments section of the DOT form.

With COPD or chest wall deformities: hypoxemia at rest as evidenced by ?? (pulse ox or ABGs)

If oximetry is less than 92% (oximetry equals 70), the driver should have an ABG analysis.

Recommend not to certify the driver when ABG measurements reveal:

  • Partial pressure of arterial oxygen (PaO2) less than:
    • 65 millimeters of mercury (mm Hg) at altitudes below 5,000 feet.
    • 60 mm Hg at altitudes above 5,000 feet.
  • Partial pressure of arterial carbon dioxide (PaCO2) greater than 45 mm Hg at any altitude.

With respiratory conditions: if driver complains of dyspnea at rest, I get a pulmonary function test.  what if driver denies it but has a diagnosis of COPD, interstitial lung disease, etc; do I do yearly PFTs to check FEV1 or (other than with asthma), will drivers be seeing specialists from whom I would get a letter?

If there is dyspnea at rest, you would order both a pulse ox and a pulmonary function test, then proceed as above.  With the aforementioned respiratory ailments you would want to see these test results at least annually, whether you get it from the specialist or have to order it yourself.

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Obstructive sleep apnea: do I take the driver’s word for compliance use with CPAP?

Definitely NO!  There is a high level of non-compliance with treatment in drivers with obstructive sleep apnea (OSA).  You must see their compliance reports that show compliance with PAP treatment 4 hours per night, 5 out of 7 nights, and an Apnea/Hypopnea Index (AHI) of under 20.  This is another situation where non-compliance is DISQUALIFYING.  When this happens, I will bring the driver back in a week or two demonstrating compliance, then progressively increase the certification period when I am happy with the compliance reports.  The driver now knows there is a risk he/she will be disqualified and unable to work if they do not comply with treatment.

We now offer a full course on Obstructive Sleep Apnea in Commercial Drivers, including how to screen, full evaluation with home sleep testing (HST) vs. formal in-lab sleep center testing, interpretation of sleep test report in consultation with a sleep specialist, PAP prescription by the sleep specialist, when to certify, disqualify or issue temporary certification, and compliance and follow up issues.

Obstructive Sleep Apnea in Commercial Drivers

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Obstructive Sleep Apnea in Commercial Drivers Course

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