Post on 17-Dec-2015
Manifestations of respiratory system dysfunctions
M. Tatar, J. Hanacek
Cardinal respiratory symptoms and signs
cough
sputum
dyspnea
wheezing
cyanosis
chest discomfort
chest pain
Disorders of lung mechanics
Disorders of the lung mechanics
• Airway obstruction– nasal cavity: nasal congestion
– pharynx: collapse during sleep
– larynx: suffocation
– central aw:
• trachea: stridor
• main bronchi: dyspnea, wheezing
• lobar bronchi: asymptomatic or minor dyspnea
– peripheral aw: dyspnea
• Lung parenchyma ( or compliance): dyspnea
• Chest wall (abnormalities): dyspnea
• Respiratory muscles (fatigue): dyspnea
Disorders of airway defence mechanisms
Disorders of airways defence mechanisms
• Nasal cavity– sneezing
– nasal dyscharge
• Airways– Cough: acute respiratory infections, foreign body
aspiration, chronic bronchitis, chronic cough
– Expectoration - Sputum• mucoid (mainly macrophages) • purulent (neutrophils) • Pneumococcus - bloody or rust-colored • Pseudomonas, Haemophilus - green sputum
Hyperplasia and hypertrophy of submucosal glands
Disorders of gas exchange
Disorders of gas exchange
Respiratory insufficiency (failure)
– Hypoxemic• Decreased ventilation/perfusion ratio• Venous admixture• Diffusion impairment
– Hypercapnic • Overall alveolar hypoventilation• Limits for hyperventilatory compensation of decreased ventilation/perfusion ratio
Vznik hypoxémie vplyvom zníženia V/Q pomeru
?
2 0 4 0 6 0 8 0 1 0 0 1 2 0 m m H gP a O 2
C
C
D
CA
C
B
C
2 0
1 0
Vol
% O
2
V yso k ý V ´A = 1 1/2
V ´A /Q ´
Q ´= 1 V ´A = 1/ 2 N ízk y
V ´A /Q ´
Q ´= 1
Fy z io lo g ic k ý V ´A /Q ´
V ´A = 1 V ´A = 1
Q ´= 1 Q ´= 1
’
Kompenzačné mechanizmy pri hyperkapnii
50
25
mmHg 20 4060
PaCO2
Vol
% C
O 2
B
A
C
Nízky V´A=2/3
V´A/Q´
Q ́= 1
V´A=11/3
Vysoký Q´=1V´A/Q´ Fyziologický V´A/Q´
Q´=1 V´A=1 V´A=1 Q´=1
11/3 + 2/3 = 2
P
Z
Disturbed regulation of breathing
Cheyne-Stokes respiration
Sleep apnea
Hyperventilation
Gasping
Hypopnea
Shortness of breath
Cheyne-Stokes breathing
General body responses
Fever
Weakness, fatigue
Decreased exercise tolerance
Immunity: eosinophilia
Weight loss: advanced disease
Cough
• Physiologic reflex
• Pathologic reflex
• Acute cough
• Chronic cough– Rhinitis/sinusitis– Asthma– Gastroesophageal reflux disease
Dyspnea
• Air hunger, chest tighness
• Subject´s feelings – needs for increased ventilatory activity
• Tachypnoea with either shallow or deep breathing
• Increased workload of respiratory muscles – normal gas
exchange cannot be achieved without increased ventilatory
effort
Pathophysiology of dyspnea
• Hyperventilation – acute hypoxemia
• Relative hyperventilation - decreased ventilatory surfice (atelectasis, pleural effusion, lung congestion, pneumotorax)
• Disordered lung mechanics (most frequent cause)- Upper airways stenosis- Increased arways resistence = obstruction of peripheral
airways (asthma, COPD, heart failure)- Decreased muscle force (polyomyelitis, diaphragm
paralysis, myastenia gravis) - Limited chest movements (kyphoscoliosis)- !!! acute or chronic state; rest or physical activity
Causes of dyspnea
oxygen content in atmosphere
oxygen consumption during physical activity
Lung function disorders
Heart function disorders
Decreased hemoglobin content (during exercise)
Respiratory center dysfunction (Cheyne-Stokes, acidosis)
Stimulation of airway and lung nerve-endings (pneumonia, lung congestion)
Obesity
Emotive factors (chronic hyperventilatory syndrom)
Brain dysorders
Metabolic dysorders – hyperthyreosis
Hypoxemia
Tachycardia, tachypnea, dyspnea, mental status changes
Secondary polycythemia ( hematocrit)
Cyanosis
threshold for central cyanosis is a capillary reduced hemoglobin content of 5 g/dL
!!! ancillary nonspecific signs
Relation between SaO2 and arterial Hb
Cyanosis
• Central – hemiglobin – methemoglobin, sulphhemoglobin – hemoglobin - content of reduced Hb
• Heart disorders – lung congestion
• Lung disorders
– acute: pneumonia, lung edema
– chronic: COPD, severe lung fibrosis
• Peripheral– local perfusion disorders
• False– pigmentation (silver)
Peripheral and central cyanosis
Peripheral Central
Hypercapnia
Morning headaches
Papilledema, dilated conjunctival and superficial facial blood vessels
CO2 narcosis: anxiety may progress to delirium and
somnolency
Primary respiratory disorders can significantly affect the
function of other systems
Most frequently CVS
Cor pulmonale elevated jugular venous pulse, peripheral edema
Massive pulmonary embolism and tension pneumothorax circulatory shock – hypotension, weakness, pale, sweaty, oliguric, and develops impaired mentation
OSAS daytime sleepiness, right heart failure, systemic arterial hypertension