Έλεγχος της λειτουργικής ικανότητας των αναπνευστικών μυών

The functional capacity and presence of respiratory muscle fatigue of 36 patients suffering from chronic obstructive pulmonary disease (COPD) and 9 normal individuals were studied using the diaphragmatic pressure-time index (PTdi). Which is the product of the ratios of inspiratory time/total respiratory cycle (Ti/Ttot) and mean Pdi per breath/maximum static Pdi (Pdi/Pdimax). a. The patients who were hypercapnic (PaCO₂ > 45cmH₂O) presented with lower mouth and transdiaphragmatic pressures compared to the normocapnic patients (PaCO₂ < 45cmH₂O), even though they did not have significant changes in lung volume and expiratory flow. Diaphragmatic fatigue demonstrated by the PTdi was more frequent in patients with hypercapnia (PTdi= 0.27±0.42) compared to the normocapnic patients (PTdi=0.14±0.10). b. The patients who had respiratory muscle fatigue exhibited slightly lower FEV₁ and FVC compared to those who did not have respiratory muscle fatigue. Blood gas pressures did not differ significantly. On the contrary, the patients with respiratory muscle fatigue had significant decreases of Pm and Pdimax, and increase of the ratio Pdi/Pdimax. c. The routine tests of respiratory function such as lung volume, expiratory flow, PaO₂ and PaCO₂ were not able to distinguish the patients who had respiratory muscle fatigue. d. The ratio RL/Pdimax can possibly predict respiratory muscle fatigue. However the measurement of total pulmonary resistances (RL) is rather difficult. e. Lung hyperinflation is a significant factor causing impairment of respiratory muscle function. If we take this into consideration the impairment of Pm in significant number of COPD patients can be attributed to an improper position of the diaphragm. z. Respiratory effective time (Ti/Ttot) and mean inspiratory flow (VT/TΙ) are factors which are easily modified (position of the patient, mouthpiece, catheters) and can affect the PTdi. An increased TI/Ttot and VT/TI of the patients that we studied could explain the fact that a significant number of our patients with normal PaCO₂ were found to be in the muscle fatigue zone. However picture 18 demonstrates that the main factor determining the distribution of our values in the fatigue or non fatigue zone is the change in Pdi/Pdi max.

Grantor dc:publisher

Aristotle University Of Thessaloniki (AUTH)

Year dc:date

1990

Authors dc:creator

• Maniki, E.
• Μανίκη, Ευριδίκη

• Ιατρική και Επιστήμες Υγείας
• Κλινική Ιατρική
• Medical and Health Sciences
• Clinical Medicine

Language dc:language

gre

Identifier

10.12681/eadd/1428

OAI identifier oai:identifier

oai:10442/1428