Adding to the repertoire of tests we offer we are hoping to be able to perform the Sniff Nasal Inspiratory Pressure (SNIP) test as soon as the nasal adaptors arrive.
SNIP has been shown useful in assessing inspiratory muscle strength, and is thought to more closely reflect changes in oesophageal pressure during inspiratory efforts.
The SNIP measurement appears to be better than MIP (Maximal inspiratory pressure) in monitoring the evolution of neuromuscular disease and may prove to be a better predictor of hypercarbia and subsequent intervention.
Indications:
To assess and quantify the degree of respiratory muscular weakness that may occur with neuromuscular disease, obstructive lung disease causing hyperinflation, chest deformities, and unexplained dyspnoea
To obtain clinical information about the potential for effective cough and ability for secretion clearance
As Maureen is demonstrating (whilst smiling I might add) in the photo, SNIP is the measurement of pressure through a plug occluding one nostril during a maximal sniff performed through the contralateral nostril. It is an accurate and non invasive approximation of oesophageal pressure swing during sniff manoeuvres but has been found to underestimate oesophageal pressure swing in subjects with nasal obstruction, patients with chronic obstructive pulmonary disease and severe neuromuscular patients.
Heritier et al[1] found that SNIP provides a reliable and noninvasive estimation of oesophageal pressure swing during sniff manoeuvres (sniffPes) in normal subjects and in patients with neuromuscular or skeletal disorders by simultaneously measuring the oesophageal pressure using an oesophageal balloon and the validity of this method may be impaired by severe nasal congestion.
In this study 10 normal subjects performed 338 sniffs of variable intensity and 12 patients with neuromuscular or skeletal disorders performed 181 maximal sniffs. Nasal mucosal congestion was induced by nebulization of increasing doses of histamine in four normal subjects.
In conclusion the SNIP manoeuvre has predicted normal values, is noninvasive and is easier to perform than MIP. It could be considered as the first simple test to use in order to assess inspiratory muscle weakness. In addition, because it is as reproducible as MIP, it can be suitable to follow inspiratory muscle function in chronic neuromuscular patients. Because, of the important limit of agreement between SNIP and MIP, these two methods are not interchangeable but complimentary.
Vanessa
[1] Heritier F, Rahm F, Pashe P & Fitting JW. 1994. Am. J. Respir. Crit Care Med., Vol 150, No 6, 12, 1678-1683.
SNIP has been shown useful in assessing inspiratory muscle strength, and is thought to more closely reflect changes in oesophageal pressure during inspiratory efforts.
The SNIP measurement appears to be better than MIP (Maximal inspiratory pressure) in monitoring the evolution of neuromuscular disease and may prove to be a better predictor of hypercarbia and subsequent intervention.
Indications:
To assess and quantify the degree of respiratory muscular weakness that may occur with neuromuscular disease, obstructive lung disease causing hyperinflation, chest deformities, and unexplained dyspnoea
To obtain clinical information about the potential for effective cough and ability for secretion clearance
As Maureen is demonstrating (whilst smiling I might add) in the photo, SNIP is the measurement of pressure through a plug occluding one nostril during a maximal sniff performed through the contralateral nostril. It is an accurate and non invasive approximation of oesophageal pressure swing during sniff manoeuvres but has been found to underestimate oesophageal pressure swing in subjects with nasal obstruction, patients with chronic obstructive pulmonary disease and severe neuromuscular patients.
Heritier et al[1] found that SNIP provides a reliable and noninvasive estimation of oesophageal pressure swing during sniff manoeuvres (sniffPes) in normal subjects and in patients with neuromuscular or skeletal disorders by simultaneously measuring the oesophageal pressure using an oesophageal balloon and the validity of this method may be impaired by severe nasal congestion.
In this study 10 normal subjects performed 338 sniffs of variable intensity and 12 patients with neuromuscular or skeletal disorders performed 181 maximal sniffs. Nasal mucosal congestion was induced by nebulization of increasing doses of histamine in four normal subjects.
In conclusion the SNIP manoeuvre has predicted normal values, is noninvasive and is easier to perform than MIP. It could be considered as the first simple test to use in order to assess inspiratory muscle weakness. In addition, because it is as reproducible as MIP, it can be suitable to follow inspiratory muscle function in chronic neuromuscular patients. Because, of the important limit of agreement between SNIP and MIP, these two methods are not interchangeable but complimentary.
Vanessa
[1] Heritier F, Rahm F, Pashe P & Fitting JW. 1994. Am. J. Respir. Crit Care Med., Vol 150, No 6, 12, 1678-1683.
This is something new I have learnt.
ReplyDeleteCan this be used in ventilated patients on a weaning mode; particularly to assess cough reflex and ability to clear secretions.