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Defining the Normal Range for Maximal Sniff Diaphragm Thickening Fraction (SNIFF II)

University Health Network, Toronto logo

University Health Network, Toronto

Status

Completed

Conditions

Diaphragm

Study type

Observational

Funder types

Other

Identifiers

NCT03129386
15-8998-AE

Details and patient eligibility

About

This study is investigating the normal range of maximal diaphragm thickness during a sniff inspiratory manoeuvre using ultrasound in healthy subjects stratified by age and gender.

Full description

Diaphragm dysfunction is associated with poor clinical outcomes in critically ill patients but is difficult to diagnose. Traditionally, diaphragm function is measured by evaluating inspiratory muscle strength via maximal inspiratory pressure (MIP). However, this technique relies on a volitional maximal effort and can be challenging for patients to perform.

An alternative to measuring inspiratory muscle strength is the sniff inspiratory pressure approach. During short, sharp sniffs, the diaphragm is maximally activated.

Currently, there are no reported values of the normal range of maximal diaphragm thickness during a sniff maneuver. This study will define the normal range of values for sniff maximal diaphragm thickening fraction, maximal thickening against an occluded airway, and diaphragm thickening during resting tidal breathing in healthy subjects.

Enrollment

60 patients

Sex

All

Ages

18+ years old

Volunteers

Accepts Healthy Volunteers

Inclusion criteria

  • Over 18 years of age

Exclusion criteria

  • Antecedent history of neuromuscular or cardiorespiratory disease

Trial contacts and locations

1

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Data sourced from clinicaltrials.gov

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