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Intra-abdominal pressures during voluntary and reflex cough
Cough (London, England)
|May 2, 2008
Summary
The laryngeal cough reflex (LCR) generates significantly higher intra-abdominal pressure (IAP) over time compared to voluntary cough (VC). This study quantifies LCR
Area of Science:
- Urogynecology
- Respiratory Physiology
- Pulmonary Medicine
Background:
- The laryngeal cough reflex (LCR) involves coordinated muscle contractions to increase intra-abdominal pressure (IAP) for airway clearance.
- Intra-abdominal pressure (IAP) changes during voluntary cough (VC) and LCR can be measured using bladder pressure catheters.
- This study investigates the physiological characteristics of IAP during VC and LCR.
Purpose of the Study:
- To evaluate and compare the physiological characteristics of IAP generated during voluntary cough (VC) and the laryngeal cough reflex (LCR).
- To quantify peak, mean, and area under the curve (AUC) IAP values for both VC and LCR.
- To explore the potential clinical utility of these measurements for assessing airway protection.
Main Methods:
- Eleven female subjects (18-75 years) underwent urodynamic assessment with an intravesicular pressure transducer.
- IAP recordings were obtained during voluntary cough (VC) and reflex cough test (RCT) induced by inhaled tartaric acid.
- Area under the curve (AUC) was calculated by integrating intravesicular pressure over time.
Main Results:
- The mean AUC for LCR (986.6 cm H2O.s) was significantly higher than for VC (349.6 cm H2O.s) (p < 0.01).
- Mean IAP values were similar (VC: 45.6 cm H2O; LCR: 44.5 cm H2O).
- Peak IAP values showed a trend towards being higher during LCR (164.9 cm H2O) compared to VC (139.5 cm H2O) (p = 0.07).
Conclusions:
- The LCR represents a rapid, involuntary expiratory muscle activation sustaining elevated IAP for airway protection.
- VC and LCR have distinct neurophysiological functions.
- Quantifying LCR via AUC and IAP may serve as a clinical tool for assessing neurophysiological airway protection and patient recovery.
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