Can voice hoarseness in a patient with End-Stage Renal Disease (ESRD) after hemodialysis (HD) indicate excessive fluid removal?

Voice Hoarseness After Dialysis and Fluid Removal

Yes, voice hoarseness after dialysis typically indicates excessive fluid removal, not insufficient removal. This occurs when ultrafiltration depletes extracellular volume too rapidly, causing dehydration of the vocal fold tissues (Reinke's space) and triggering autonomic nervous system responses that affect laryngeal function.

Mechanism of Post-Dialysis Hoarseness

The primary pathophysiology involves vocal fold dehydration from excessive ultrafiltration. When fluid is removed too aggressively during hemodialysis, the vocal folds lose tissue hydration, resulting in:

• Decreased vocal fold thickness documented on objective examination after dialysis sessions 1
• Incomplete glottic closure due to bowing of the vocal folds from volume depletion 2
• Increased phonation threshold pressure when body fluid is reduced by 3-4% of body weight, even without clinical dehydration 3

The American Academy of Otolaryngology guidelines specifically note that objective findings of hoarseness and vocal fold thickness changes were found in patients with post-dialysis dehydration 1.

Clinical Evidence Supporting Excessive Fluid Removal

Research demonstrates that hoarseness correlates directly with the degree of fluid removal:

• 15.2% of hemodialysis patients experience post-dialysis hoarseness, with duration ranging from 1 to 24 hours 4
• Fundamental frequency (Fo) increases significantly from 164.52±43.36 Hz to 193.19±47.08 Hz after dialysis, indicating vocal fold tension from dehydration 5
• Harmonic-to-noise ratio (HNR) decreases significantly from 16.10±4.06 dB to 4.6±3.23 dB, reflecting deteriorating voice quality 5
• Ultrafiltration volume shows highly significant correlation with voice changes—the more fluid removed, the greater the voice change 5

Risk Factors for Dialysis-Induced Hoarseness

Patients most vulnerable to post-dialysis hoarseness share characteristics of those prone to intradialytic hypotension:

• Older age is significantly associated with severe and moderate hoarseness 4
• Coronary artery disease increases risk of severe hoarseness 4
• Autonomic neuropathy (particularly in diabetic patients) strongly predicts hoarseness severity 4
• Severe intradialytic hypotensive episodes are the strongest predictor of hoarseness 4
• Cardiovascular compromise including congestive heart failure, valve abnormalities, and left ventricular diastolic dysfunction 4

The mechanism appears mediated by autonomic nervous control related to volume depletion—the same pathway that causes intradialytic hypotension 4, 3.

Distinguishing Excessive vs. Inadequate Fluid Removal

This is a critical clinical distinction. The question implies concern that hoarseness might indicate inadequate fluid removal (persistent volume overload), but the evidence overwhelmingly demonstrates the opposite:

• Hoarseness correlates with greater systolic blood pressure drops during dialysis—patients with severe hoarseness had significantly larger BP decreases than those with mild hoarseness 4
• Phonation threshold pressure increases with net ultrafiltration rates ≥1.0 L/hour, indicating rapid volume depletion 3
• Post-dialysis body weight shows highly significant correlation with voice changes—lower post-dialysis weight predicts worse voice parameters 5

If fluid removal were inadequate, patients would have persistent hypertension and volume overload signs, not hoarseness 1.

Management Approach

When a patient develops hoarseness after dialysis, this signals that ultrafiltration has exceeded physiologic tolerance:

1. Immediately increase the dry weight target by 0.3-0.5 kg for subsequent sessions 6
2. Reduce ultrafiltration rate to allow plasma refilling to compensate—target rates below 10 mL/h/kg 6
3. Extend dialysis session duration rather than accelerating ultrafiltration, as conventional 4-hour sessions may be too short for safe fluid removal 1, 6
4. Consider additional dialysis sessions (short daily or nocturnal regimens) to achieve volume goals without excessive ultrafiltration rates 1

Common Pitfall to Avoid

Do not interpret post-dialysis hoarseness as a sign to remove more fluid. This represents a dangerous misunderstanding of the physiology. The American Journal of Kidney Diseases guidelines emphasize that hypotension during dialysis signals that ultrafiltration has depleted intravascular volume faster than plasma refilling can compensate, meaning the patient has reached or gone below their actual dry weight 6.

Hoarseness functions as an early warning sign of excessive volume depletion, similar to but potentially preceding frank hypotension 4, 3.

Objective Voice Analysis as a Clinical Tool

Voice analysis may serve as a non-invasive method to assess adequacy of fluid removal:

• Fundamental frequency measurements can objectively document voice changes before patients develop symptomatic hypotension 5
• Harmonic-to-noise ratio reduction correlates with blood pressure changes during dialysis 5
• Research suggests objective voice analysis could help determine optimal dry weight by identifying the threshold where excessive fluid removal begins 5

However, this remains investigational and is not yet standard clinical practice 2.