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Updated: May 17, 2026
09:47
Standardized Measurement of Nasal Membrane Transepithelial Potential Difference (NPD)
Published on: September 13, 2018
Influence of perfusate temperature on nasal potential difference
Inez Bronsveld1, François Vermeulen, Dorotha Sands
1University Medical Centre Utrecht, Utrecht, The Netherlands.
The European Respiratory Journal
|October 27, 2012
Summary
Room temperature solutions are recommended for nasal potential difference (NPD) measurements in cystic fibrosis research. Warmed solutions increase variability, potentially impacting the power of clinical trials investigating new therapies.
Area of Science:
- Pulmonary Medicine
- Physiology
- Medical Diagnostics
Background:
- Nasal potential difference (NPD) is a key diagnostic tool for cystic fibrosis, reflecting abnormal ion transport.
- NPD is increasingly utilized as an outcome measure in clinical trials for novel cystic fibrosis therapies.
Purpose of the Study:
- To investigate the impact of solution temperature on NPD measurements.
- To determine optimal conditions for reliable NPD assessment in cystic fibrosis research.
Main Methods:
- NPD was measured in subjects using both room temperature (20-25°C) and warmed (32-37°C) solutions.
- Solution temperature effects were assessed by switching temperatures during perfusion steps and by repeating full protocols at different temperatures within the same subjects.
Main Results:
- Solution temperature changes had minimal effect on NPD during Ringer's solution perfusion.
- Switching to warmed solutions during zero chloride perfusion tended to decrease NPD, while switching back to room temperature increased it (p<0.05).
- Warmed solutions during isoprenaline perfusion significantly altered NPD (p<0.01), and increased variability in chloride response measurements.
Conclusions:
- Room temperature solutions are recommended for NPD measurements to minimize variability.
- Standardizing solution temperature to room temperature may enhance the statistical power of cystic fibrosis clinical trials.
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