An MSLT After Five Hours of Sleep and a Request to Omit a Medication
A 34-year-old woman is scheduled for a multiple sleep latency test following her overnight polysomnography. On intake she reports averaging 5–6 hours of sleep per night, rotating shift work with two night shifts in the past week, daily venlafaxine 150 mg for depression, and near-daily cannabis use at bedtime. Her overnight study shows a sleep efficiency of 78%, an AHI of 1.2/hour, and a REM latency of 68 minutes. She asks the technologist not to record the cannabis use because her employer will see the report, and she asks whether she can take a stimulant she has left over from an old prescription to "get through" the test day.
1. Should the MSLT proceed as scheduled? Identify the threats to validity and what you would do before the first nap.
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- Insufficient sleep is disqualifying. An MSLT is interpretable only after a preceding PSG documents adequate sleep (generally at least 6 hours in an adult; many protocols want 7–8). At 5–6 hours habitual sleep with 78% efficiency, a short mean sleep latency would be uninterpretable - it could reflect chronic sleep restriction rather than a central disorder of hypersomnolence.
- Shift work disrupts circadian timing; the protocol expects a stable sleep–wake schedule documented by actigraphy for the 1–2 weeks before testing. Two night shifts in the past week undermine that.
- Venlafaxine suppresses REM and can produce a false-negative MSLT (and REM rebound if stopped abruptly); cannabis also alters REM architecture and sleep onset. Both need to be reviewed by the interpreting physician, who decides whether testing should be deferred or the medication adjusted - that is not a technologist decision.
- Action: do not start the nap series on your own authority. Contact the interpreting physician before the first nap, document the conversation, and be prepared to defer.
2. How do you handle her request that the cannabis use be left out of the record?
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- You cannot omit it. The medication and substance history is part of the clinical data the interpreting physician needs, and an inaccurate record is a documentation violation regardless of the patient's reason.
- Explain the limits of disclosure calmly and factually: the polysomnogram report goes to the referring provider, and release to an employer requires the patient's authorization unless a specific legal exception applies. She can discuss those limits with the physician or the laboratory's privacy officer.
- Do not bargain or promise. Saying "I'll leave it off" to reduce her anxiety creates a false record and puts you in an indefensible position.
- Escalate if she insists or becomes distressed - involve the medical director or the privacy officer rather than resolving it at the bedside.
- Document the disclosure as given, in the patient's own terms, along with the fact that she raised a concern about employer access.
3. What is your response to the leftover stimulant, and what else must you address before she leaves?
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- Refuse, and explain why: stimulants taken on the test day will shorten sleep latencies and invalidate the MSLT, and taking a medication prescribed to her for a previous episode, without a current order, is not something the laboratory can sanction. All stimulants, wake-promoters, and REM-suppressing agents must be reviewed and withheld or continued only by physician order.
- Screen for other sources of stimulant - caffeine, decongestants, energy drinks - and record the last intake.
- Tell the physician that she asked, since it is relevant to the assessment (and to whether she is self-medicating for sleepiness).
- Address fitness to drive: a patient presenting for evaluation of excessive daytime sleepiness who has just driven to the laboratory may be unsafe on the road, and after a day of naps she will be no better. Arrange for someone to collect her or discuss alternatives, and document the conversation.
- Do not let the schedule pressure you into proceeding. A deferred, well-documented study is a better outcome than an uninterpretable one.