Vital capacity decreased in supine position
Returned blood volume increased pulmo edema
Sensitivity of respiratory center decreased after obvious hypoxia
Mechanism of left heart failure
Pulmo edema diffusion capacity decreased
Alveolar tension increased stimulating stretch receptor excitation of vagus nerve excitation of respiratory center
Expiratory dyspnea ____obstruction in small airway or alveolar elasticity
decreased – Prolonged expiratory time – Expiratory rhonchi
Mixed dyspnea ____deficient gas exchange
– Respiratory rate increased – Shallow breathing
supraclavicular fossa
suprasternal fossa
intercostal space
Three depression Heart failure
– Diaphragma movement disorder: obviously elevated pressure in abdominal cavity
Etiology
2 . Cardio-vascular system diseases
1 Heart failure 2 pericardial tamponade 3 pulmonary artery hypertension 4 Pulmonary thromboembolism
Characteristic: Respiration speeds up.
Mechanism: Volume of oxygen carried by red blood cells decreases. Blood oxygen content: ↓
Blood pressure after blood loss: ↓---reflection RR ↑.
mental factor
Expression
Dyspnea with Pulmonary Origin
1）Inhalation Dyspnea: Characteristics /Common Pathogeny
2）Exhalation Dyspnea: Characteristics /Common Pathogeny
expanded heart,
Treatment:
digitalis, drugs for blood
vessel expandion,
Teenager hyper-sensibility, family medical history winter, spring, autumn rhonchi heart（-） emphysema normal
Mechanism: metabolic acidosis drug-induced respiration restrain
Skull pressure↑respiratory center restraint
Mechanism and Expression
4. Dyspnea Induced by Blood Diseases
3. Toxication
Etiology
1）Uraemia 2） diabetes ketoacidosis 3）Drug-induced toxication: morphine,
organic phosphor, nitrite, cyanide
4）carbon monoxide poisoning
------Diaphragmatic muscle dyskinesia
•Congestive hepatomegaly and hydrothorax ascites
Mechanism and Expression
Identification of Cardiac-Origin Dyspnea from Asthma
III. Mechanism and Clinical feature of Dyspnea
Mechanism
1. With pulmonary origin 2. With cardiac origin 3. Induced by toxication 4. Induced by blood 5. Induced by neural or
– Obstruction: asthma, COPD, tumor
– Pulmo Diseases: pneumonia, interstitial lung disease,
– Chest wall or pleura: pleurisy, pneumothorax, trauma
– neuro-muscles: poliomyelitis ( 脊髓灰质炎), myasthenia gravis (重症肌无力)
Dyspnea
I. Definition
Subjective Awareness of difficulty breathing ; shortness of breath
Objective Expression: toilful breathing action (with nosewing inhaling and furling, mouth open, shoulders hunching, face turning dark purple, and accessory muscles of respiration participating in the action), abnormal frequency, depth and rhythm of breath.
spasm relief drugs.
Mechanism and Expression
3. Toxication-induced Dyspnea
Characteristics: Kussmoul（deep, slow）, Cheyne-Stokes（tidal breathing）, Biots（intermittent breathing）:
Nocturnal paroxysmal dyspnea
Characteristics
Awoken due to chest tightness or dyspnea Forced sitting position or orthopnea Severe sweat Tachycardia Moist crackles or rhonchi in both lungs Pink frothy sputum
Mechanism and Expression
5. Dyspnea Induced by Neural or Mental Factor
II. Etiology
1. Respiratory system diseases 2. Cardio-vascular system diseases 3. Toxication 4. Hemopathy 5. Neural and mental factors
Etiology
1. Respiratory system diseases
4. Hemopathy
Etiology
1）serious anemia 2）High-iron-content hemoglobin 3）Abnormal hemoglobin
Etiology
5. Neural and mental factors
1）Respiratory nerve center obstacle, cranial trauma, cerebral hemorrhage, cerebral tumor, encephalitis and meningitis 2）Mental factor: hysteria
Alveolar elasticity decreased vital capacity decreased
Increased pressure of pulmo circulation respiratory center
stimulating
Features of left heart failure
Nocturnal paroxysmal
Mechanism
dyspnea
Elevated excitation of vagus nerve
Contraction of coronary artery myocardium ischemia
Contraction of bronchiole decreased alveolar ventilation
reaction
Mechanism and Expression
2 . Dyspnea with Cardiac Origin-- Right Heart Failure:
Expression: extravasated blood
in body circulation
Mechanism: -----baroreceptor • pressure of right atrium↑ • pressure of superior cava vena ↑ ----SO2 •acidic product of metabolism ↑