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Effects of diaphragmatic control on the assessment of sniff nasal inspiratory pressure and maximum relaxation rate.

Benício K, Dias FA, Gualdi LP, Aliverti A, Resqueti VR, Fregonezi GA - Braz J Phys Ther (2015)

Bottom Line: SNIP values were significantly different in maneuvers with and without diaphC [without diaphC: -100 (SD=27.1) cmH2O/ with diaphC: -72.8 (SD=22.3) cmH2O; p<0.0001], normalized MRR values were not statistically different [without diaphC: -9.7 (SD=2.6); with diaphC: -8.9 (SD=1.5); p=0.19].Without diaphC, 40% of the sample did not reach the appropriate sniff criteria found in the literature.However, there was no influence on normalized MRR.

View Article: PubMed Central - PubMed

Affiliation: Departamento de Fisioterapia, Universidade Federal do Rio Grande do Norte, Natal, RN, Brazil.

ABSTRACT

Objective: To assess the influence of diaphragmatic activation control (diaphC) on Sniff Nasal-Inspiratory Pressure (SNIP) and Maximum Relaxation Rate of inspiratory muscles (MRR) in healthy subjects.

Method: Twenty subjects (9 male; age: 23 (SD=2.9) years; BMI: 23.8 (SD=3) kg/m²; FEV1/FVC: 0.9 (SD=0.1)] performed 5 sniff maneuvers in two different moments: with or without instruction on diaphC. Before the first maneuver, a brief explanation was given to the subjects on how to perform the sniff test. For sniff test with diaphC, subjects were instructed to perform intense diaphragm activation. The best SNIP and MRR values were used for analysis. MRR was calculated as the ratio of first derivative of pressure over time (dP/dtmax) and were normalized by dividing it by peak pressure (SNIP) from the same maneuver.

Results: SNIP values were significantly different in maneuvers with and without diaphC [without diaphC: -100 (SD=27.1) cmH2O/ with diaphC: -72.8 (SD=22.3) cmH2O; p<0.0001], normalized MRR values were not statistically different [without diaphC: -9.7 (SD=2.6); with diaphC: -8.9 (SD=1.5); p=0.19]. Without diaphC, 40% of the sample did not reach the appropriate sniff criteria found in the literature.

Conclusion: Diaphragmatic control performed during SNIP test influences obtained inspiratory pressure, being lower when diaphC is performed. However, there was no influence on normalized MRR.

No MeSH data available.


Graphic representation of Sniff Nasal-Inspiratory Pressure (SNIP) kinetics.Figure (A) without diaphragmatic control and (B) with diaphragmatic control inthe same subject. On the left, there is a peak pressure of ~130cmH2O and a total duration time of sniff ~630 milliseconds; on theright, there is a peak pressure of ~103 cmH2O and a total durationtime of ~350 milliseconds. diaphC: diaphragmatic activation control.
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f03: Graphic representation of Sniff Nasal-Inspiratory Pressure (SNIP) kinetics.Figure (A) without diaphragmatic control and (B) with diaphragmatic control inthe same subject. On the left, there is a peak pressure of ~130cmH2O and a total duration time of sniff ~630 milliseconds; on theright, there is a peak pressure of ~103 cmH2O and a total durationtime of ~350 milliseconds. diaphC: diaphragmatic activation control.

Mentions: Figure 3 illustrates the kinetic pattern of SNIPtests for a single individual with and without DiaphCtrl, showing the shape of the SNIPcurve and Ttotal for the maneuver. Maneuvers with DiaphCtrl exhibited a lowerTtotal than those executed without DiaphCtrl. In maneuvers withoutDiaphCtrl, 40% (n=8) of subjects obtained a Ttotal higher than 500 ms.However, in maneuvers with DiaphCtrl (assessment B), 100% (n=20) of subjects achieved aTtotal lower than 500 ms, as shown in Table 2.


Effects of diaphragmatic control on the assessment of sniff nasal inspiratory pressure and maximum relaxation rate.

Benício K, Dias FA, Gualdi LP, Aliverti A, Resqueti VR, Fregonezi GA - Braz J Phys Ther (2015)

Graphic representation of Sniff Nasal-Inspiratory Pressure (SNIP) kinetics.Figure (A) without diaphragmatic control and (B) with diaphragmatic control inthe same subject. On the left, there is a peak pressure of ~130cmH2O and a total duration time of sniff ~630 milliseconds; on theright, there is a peak pressure of ~103 cmH2O and a total durationtime of ~350 milliseconds. diaphC: diaphragmatic activation control.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4835170&req=5

f03: Graphic representation of Sniff Nasal-Inspiratory Pressure (SNIP) kinetics.Figure (A) without diaphragmatic control and (B) with diaphragmatic control inthe same subject. On the left, there is a peak pressure of ~130cmH2O and a total duration time of sniff ~630 milliseconds; on theright, there is a peak pressure of ~103 cmH2O and a total durationtime of ~350 milliseconds. diaphC: diaphragmatic activation control.
Mentions: Figure 3 illustrates the kinetic pattern of SNIPtests for a single individual with and without DiaphCtrl, showing the shape of the SNIPcurve and Ttotal for the maneuver. Maneuvers with DiaphCtrl exhibited a lowerTtotal than those executed without DiaphCtrl. In maneuvers withoutDiaphCtrl, 40% (n=8) of subjects obtained a Ttotal higher than 500 ms.However, in maneuvers with DiaphCtrl (assessment B), 100% (n=20) of subjects achieved aTtotal lower than 500 ms, as shown in Table 2.

Bottom Line: SNIP values were significantly different in maneuvers with and without diaphC [without diaphC: -100 (SD=27.1) cmH2O/ with diaphC: -72.8 (SD=22.3) cmH2O; p<0.0001], normalized MRR values were not statistically different [without diaphC: -9.7 (SD=2.6); with diaphC: -8.9 (SD=1.5); p=0.19].Without diaphC, 40% of the sample did not reach the appropriate sniff criteria found in the literature.However, there was no influence on normalized MRR.

View Article: PubMed Central - PubMed

Affiliation: Departamento de Fisioterapia, Universidade Federal do Rio Grande do Norte, Natal, RN, Brazil.

ABSTRACT

Objective: To assess the influence of diaphragmatic activation control (diaphC) on Sniff Nasal-Inspiratory Pressure (SNIP) and Maximum Relaxation Rate of inspiratory muscles (MRR) in healthy subjects.

Method: Twenty subjects (9 male; age: 23 (SD=2.9) years; BMI: 23.8 (SD=3) kg/m²; FEV1/FVC: 0.9 (SD=0.1)] performed 5 sniff maneuvers in two different moments: with or without instruction on diaphC. Before the first maneuver, a brief explanation was given to the subjects on how to perform the sniff test. For sniff test with diaphC, subjects were instructed to perform intense diaphragm activation. The best SNIP and MRR values were used for analysis. MRR was calculated as the ratio of first derivative of pressure over time (dP/dtmax) and were normalized by dividing it by peak pressure (SNIP) from the same maneuver.

Results: SNIP values were significantly different in maneuvers with and without diaphC [without diaphC: -100 (SD=27.1) cmH2O/ with diaphC: -72.8 (SD=22.3) cmH2O; p<0.0001], normalized MRR values were not statistically different [without diaphC: -9.7 (SD=2.6); with diaphC: -8.9 (SD=1.5); p=0.19]. Without diaphC, 40% of the sample did not reach the appropriate sniff criteria found in the literature.

Conclusion: Diaphragmatic control performed during SNIP test influences obtained inspiratory pressure, being lower when diaphC is performed. However, there was no influence on normalized MRR.

No MeSH data available.