Symptoms of pulmonary edema

The lungs of our human body play a very important role. Our lungs are used for breathing. It is conceivable that if there is a problem with our lungs, it will have a serious impact on our breathing and cause various problems in our body. Therefore, we need to understand some common lung diseases, which will help us protect our lungs.

Pulmonary edema is a common lung disease. Once we have pulmonary edema, it will cause serious damage to our body, so we must understand some symptoms of pulmonary edema. Once the symptoms of pulmonary edema appear, we must seek treatment in time.

Pulmonary edema refers to the imbalance in the production and reflux of tissue fluid in the lungs caused by some reason, which makes a large amount of tissue fluid unable to be absorbed by the pulmonary lymphatic and pulmonary venous systems in a very short time. It seeps out of the pulmonary capillaries and accumulates in the alveoli, pulmonary interstitium and small bronchi, thus causing serious obstruction of pulmonary ventilation and gas exchange function. Clinically, the disease manifests as extreme dyspnea, orthopnea, cyanosis, profuse sweating, paroxysmal coughing accompanied by large amounts of white or pink foamy sputum, and symmetrical moist rales in both lungs.

During the interstitial stage of pulmonary edema, patients often have cough, chest tightness, and mild shallow and rapid breathing. Physical examination may reveal wheezing in both lungs, and signs of heart disease may be found in cardiogenic pulmonary edema. Both PaO2 and PaCO2 decreased slightly. After pulmonary edema fluid infiltrates into the alveoli, the patient may appear pale, cyanotic, have severe breathing difficulties, cough up large amounts of white or bloody foamy sputum, and have moist rales in both lungs. Blood gas analysis showed worsening hypoxemia, even CO2 retention and mixed acidosis.

The causes of pulmonary edema can be divided into two categories according to the anatomical location: cardiogenic and non-cardiogenic. The latter can be divided into several types according to different pathogenesis.

Symptoms of pulmonary edema

1. Cardiogenic pulmonary edema

In certain pathological conditions, such as a sharp increase in the amount of blood returning to the heart and the right heart output or a sudden and severe decrease in the left heart output, a large amount of blood accumulates in the pulmonary circulation, causing the pulmonary capillary venous pressure to rise sharply. When it rises to a level that exceeds the colloid osmotic pressure in the pulmonary capillaries, on the one hand, the hemodynamics in the capillaries change, and on the other hand, the pulmonary circulation becomes congested, the permeability of the pulmonary capillary walls increases, and fluid is filtered out through the capillary walls, forming pulmonary edema. Clinically, acute pulmonary edema caused by hypertensive heart disease, coronary heart disease and rheumatic heart valvular disease accounts for the vast majority of cardiogenic pulmonary edema. Myocarditis, cardiomyopathy, congenital heart disease and severe tachyarrhythmia can also cause it.

2. Non-cardiogenic pulmonary edema

(1) Increased permeability of pulmonary capillaries ① Infectious pulmonary edema: caused by systemic and/or pulmonary infections such as bacteria, viruses, fungi, mycoplasmas, protozoa, etc. ② Inhalation of harmful gases: such as phosgene (COCl2), chlorine, ozone, carbon monoxide, nitrogen oxides, etc. ③Blood circulating toxins and vasoactive substances: such as alloxan, snake venom, organophosphorus, histamine, 5-hydroxytryptamine, etc. ④ Diffuse capillary leak syndrome: such as endotoxemia, large-scale use of biological agents, etc. ⑤ Severe burns and disseminated intravascular coagulation. ⑥ Allergic reaction, plus drug-specific reaction, allergic alveolitis, etc. ⑦ Radiation pneumonitis: High-dose radiotherapy for chest malignant tumors can cause pulmonary edema. ⑧Uremia: Uremic pneumonia is a manifestation of pulmonary edema. ⑨Drowning: Drowning in both fresh water and sea water can cause pulmonary edema. ⑩Acute respiratory distress syndrome: the most serious acute pulmonary interstitial edema caused by various reasons. ?Oxygen poisoning: Long-term inhalation of high-concentration oxygen (>60%) can lead to an increase in reactive oxygen free radicals, causing lung damage and pulmonary edema.

(2) Increased pulmonary capillary pressure ① Pulmonary venous occlusive disease or pulmonary vein stenosis. ② Overdose of infusion.

(3) Decreased plasma colloid osmotic pressure ① Liver and kidney diseases cause hypoproteinemia. ② Protein-losing enteropathy. ③ Malnutrition-induced hypoproteinemia.

(4) Lymphatic circulation disorder

(5) Increased negative pressure in tissue compartments ① Pulmonary edema after re-expansion: If pneumothorax, pleural effusion or lung collapse occurs after thoracic surgery, the lung will re-expand rapidly after rapid venting and fluid extraction, and the negative pressure in the tissue compartment will increase, resulting in acute pulmonary edema. ② Post-obstructive pulmonary edema: acute pulmonary edema that occurs rapidly after upper airway obstruction caused by various reasons, such as endotracheal intubation and tracheotomy, is relieved.

(6) Other complex factors ① High altitude pulmonary edema: Pulmonary edema caused by high altitude hypoxia environment is called high altitude pulmonary edema. ② Drug-induced pulmonary edema: such as aspirin, heroin, lidocaine, furantidine, chlordiazepoxide, terbutaline, methadone, etc. In addition to some drugs being related to allergic factors, some drugs mainly cause direct damage to lung tissue or direct effects on the central nervous system, causing acute pulmonary edema. ③ Neurogenic pulmonary edema: Acute pulmonary edema caused by increased intracranial pressure due to craniocerebral trauma, surgery, subarachnoid hemorrhage, cerebral embolism and intracranial tumors.

Above, we introduced the important role of lungs in our human body. Our lungs are organs used for breathing. Once there is a problem with our lungs, it will affect our breathing and our physical health. The pulmonary edema mentioned above is a common lung disease. We have introduced the symptoms of pulmonary edema in detail.