Sniff Nasal Inspiratory Pressure in Healthy Individuals in Ahmadabad

Conventional method to assess inspiratory muscle strength is performed using mouth pressure measurements obtained during maximal inspiratory effort against an occlusion for at least 1 sec (PImax).¹ Sniff Nasal Inspiratory Pressure (SNIP) is an accurate and noninvasive approximation of esophageal pressure swing during sniff maneuvers. Though it underestimates inspiratory muscle strength in some subjects, since SNIP is noninvasive and is easier to perform than PImax, it can be considered as the first simple test to assess inspiratory muscle weakness. SNIP and PImax may reflect the different aspect of inspiratory muscle function² and it is reported that activity and strength of diaphragm is better evaluated by SNIP than PImax.^{3, 4, 5} SNIP can be used to measure inspiratory pressure in patients with neuromuscular or musculoskeletal disease in whom it is impossible to measure VC and PImax.⁶

To determine normal values of sniff nasal inspiratory pressure for healthy individuals in ahmadabad

Cross-sectional observational study was carried out on 100 randomly selected healthy subjects aged between 18 to 40 years (43 males & 57 females) who were either student or staff of Govt. physiotherapy college, Ahmadabad and fulfilled the inclusion and exclusion criteria. SNIP was measured using Micro Respiratory Pressure Measurement (Micro RPM) device. Data analysis was done using Microsoft excel-2003. Mean and SD were calculated.

Mean and SD values of SNIP are 55.0±28.9 cm H₂O for men and 38.0±20.0 cm H₂O for women. The mean SNIP is significantly lower for women than for men.

The present study provides useful normative data for assessing sniff nasal inspiratory pressure in Ahmadabad population which may be used as an additive tool to measure inspiratory muscle strength in future.