What is the best next step in evaluating a patient with a pituitary macroadenoma and no reported sleep-related issues before undergoing hypophysectomy?

Polysomnogram is the Best Next Step

This patient with acromegaly from a growth hormone-producing pituitary macroadenoma requires polysomnography before hypophysectomy, regardless of his reported sleep quality and lack of subjective symptoms. 1

Rationale for Sleep Study in Acromegaly

High Prevalence of Occult Sleep-Disordered Breathing

• Patients with acromegaly have a markedly elevated risk of obstructive sleep apnea (OSA), with prevalence rates exceeding 60-80% in this population, even when asymptomatic 2, 3
• The anatomical changes characteristic of acromegaly—including macroglossia (prominent tongue noted on exam), soft tissue hypertrophy, and craniofacial changes (frontal bossing documented)—predispose to upper airway obstruction during sleep 2
• The absence of a bed partner means this patient cannot report witnessed apneas or snoring, which are key symptoms that would otherwise raise clinical suspicion 2
• A normal Epworth Sleepiness Scale score does not exclude OSA, as many patients with acromegaly have OSA without excessive daytime sleepiness 2, 3

Critical Perioperative Implications

• Undiagnosed OSA significantly increases perioperative morbidity and mortality, including risks of difficult intubation, postoperative respiratory complications, and cardiovascular events 1
• Patients with acromegaly undergoing transsphenoidal hypophysectomy face additional airway management challenges due to their anatomical abnormalities, making preoperative identification of OSA essential for anesthetic planning 1, 2
• The endocrinologist's referral specifically for "evaluation of a possible sleep disorder before undergoing hypophysectomy" reflects appropriate recognition of this perioperative risk 1

Why Other Options Are Inadequate

• Overnight oximetry alone has insufficient sensitivity and specificity for diagnosing OSA, particularly in detecting hypopneas and respiratory effort-related arousals that are common in acromegaly 2
• Reassurance would be inappropriate given the high pretest probability of OSA in this population and the significant perioperative implications of missed diagnosis 1, 2

Clinical Approach

Polysomnography Protocol

• Full in-laboratory polysomnography is preferred over home sleep apnea testing in acromegaly patients due to the complexity of their sleep-disordered breathing patterns 2
• The study should assess for OSA severity, central sleep apnea (which can also occur in acromegaly), and nocturnal hypoventilation 2

Impact on Surgical Planning

• If OSA is diagnosed, perioperative management should include coordination with anesthesiology regarding difficult airway protocols and postoperative continuous positive airway pressure (CPAP) therapy 1
• Severe OSA may warrant preoperative CPAP initiation to optimize perioperative outcomes, though this should not significantly delay necessary surgery 1
• The surgical team should be alerted to anatomical findings that increase intubation difficulty 1, 2

Common Pitfall to Avoid

Do not rely on subjective sleep quality or the absence of classic OSA symptoms to exclude sleep-disordered breathing in acromegaly patients. The disease-specific anatomical changes create OSA risk independent of typical symptomatology, and the lack of a bed partner eliminates a crucial source of collateral history 2, 3