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Normal values for phrenic nerve latency in children

R I Russell1, B A Helps, P J Helms

  • 1Department of Paediatrics, Box 181, Addenbrooke's Hospital, Hills Road, Cambridge CB2 2QQ, UK. robert-ross-russell@addenbrookes.nhs.uk

Muscle & Nerve
|December 18, 2001
PubMed

Insights

This study presents the largest dataset on normal phrenic nerve latency in children, revealing a distinct age-related pattern. Phrenic nerve conduction time varies significantly across different pediatric age groups.

Area of Science:

  • Pediatric Neurology
  • Electrophysiology
  • Nerve Conduction Studies

Background:

  • Phrenic nerve latency is a crucial electrophysiological parameter.
  • Previous studies on normal pediatric phrenic nerve latency have shown inconsistencies.
  • Establishing normative data is essential for diagnosing phrenic nerve dysfunction in children.

Purpose of the Study:

  • To present comprehensive data on normal phrenic nerve latency in a large pediatric cohort.
  • To identify age-specific reference values for phrenic nerve conduction time.
  • To highlight discrepancies with existing literature.

Main Methods:

  • Phrenic nerve latency was measured in a large group of healthy children.
  • Data were collected across various age ranges from infancy to adolescence.
  • Statistical analysis was performed to determine normative values and relationships.

Main Results:

  • Phrenic nerve latency exhibits a curvilinear relationship with age in children.
  • Average latency is 6.0 ms (0-6 months), decreases to 4.8 ms (1-2 years), and increases to 6.3 ms (10-18 years).
  • Significant differences were observed compared to previous studies.

Conclusions:

  • The findings establish new, detailed normative data for pediatric phrenic nerve latency.
  • Age-specific reference ranges are crucial for accurate clinical interpretation.
  • This study provides the largest dataset to date for normal phrenic nerve latency in children.

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