Respiratory Physiology Flashcards
What is pulmonary function testing used for?
Assess lung volumes and capacities and airway function
How is pulmonary function tested?
Forced expiration and compared to normative data
What are lung volumes?
Air being moved during a breath
1) Tidal volume (VT) 500 ml
2) Inspiratory Reserve Volume (IRV) 3000ml
3) Expiratory Reserve Volume (ERV) 1100 ml
4) Residual volume (RV) 1200ml
What are lung capacities?
Sum of two or more volumes
1) Vital capacity = VT + IRV + ERV 4600ml
2) Total lung Capacity = VC + RV 5800ml
3) Inspiratory Capacity = VT + IRV 3500ml
4) Functional residual capacity = RV + ERV 2300 ml
What is FEV1 and FVC?
FVC is force vital capacity = the max amount of air forcefully exhaled
FEV1 is forced expiratory volume = the max amount of air exhaled in one second (80% is normal)
What are Obstructive Lung Diseases?
Chronic obstructive pulmonary disease Reduced airflow due to increased airway resistance Airway narrow after exhaustion -Asthma -Obstructive Sleep Apnea -Chronic Obstructive Pulmonary Disease (COPD) - Chronic bronchitis - Emphysema
Characteristics of asthma
Inflammatory condition Bronchocontriction Symptoms are shortness of breath Caused by change in temp or humidity and exercise Treated with medication
What is COPD
Obstruction due to airway inflammation and excess mucus
Decreases O2 delivery
Emphysema there is a destruction of alveoli
S/S
-Shortness of breath, cough, sputum, wheezing, decreased O2 and exercise intolerance
Treatment
-Stop smoking
- Medication
What is restrictive lung disease
Volume and flow is reduced due to restriction in the expansion of the lung
Increased work of breathing and inadequate ventilation
Alterations of the parenchyma or the pleura, chest wall or nueromuscular disease
S/S
- Shortness of breath
Treatments
- Stop smoking
-Vary
-Medication/ O2 therapy
-Lung transplant
Lung Cancer
Uncontrolled cell growth of lung tissue
Treatment
-Lobectomy or Pneumonectomy
-Chemo/radiation
Regulation of ventilation
Autonomic process
Regulated by a network of neurons in the pons and medulla
Contraction of the diaphragm and other respiratory muscles are initiated by spontaneously firing neurons
Pacemaker neurons have unstable membrane potential which make up central pattern generators with intrinsic rhythmic activity
Central and peripheral chemo-receptor regulation of ventilation
CO2 is primary stimulus
O2 and pH play lesser role
Homeostatic reflexes are continuous to keep PCO2 and PO2 and pH normal
Neural Control of Ventilation
Higher Brain Center
Cerebral cortex and hypothalamus alter activity of central pattern generator
Breathing can be voluntary
Not required for ventiliation
Neural Control of Ventilation
Limbic System
Emotional responses alter respiration
Ventilatory Response to Exercise
Exchange O2 and CO2 with blood
Allows for normal PO2 and PCO2 in arterial blood
Exercise increases O2 uptake and CO2 clearance due to increased metabolism
When VO2 and VCO2 differ, VA cannot meet demand = cannot regulate simultaneously
