72-year-old Xu was diagnosed with lung adenocarcinoma two years ago. Because he was inoperable, he received chemotherapy, radiotherapy, anti-angiogenesis and other treatments to control his condition for two years. CT revealed liver metastasis. The old man was very resistant to hospitalization. After the liver metastasis, there was no standardized treatment. Gradually, his lower extremities became swollen. Go to the hospital immediately.
Why does swelling occur in late stage tumors? This is like the three-year natural disaster in the country around 1960. Everyone did not eat or drink, and edema gradually appeared. The edema is due to malnutrition and the albumin in the body is too low, which is what we call hypoalbuminemia. Hypoalbuminemia manifests as a drop in total protein, albumin, or prealbumin on the laboratory sheet.
Blood flows in the blood vessels of the human body. 70% of the blood is water. There are actually gaps between the epithelial cells of the blood vessel walls. Will the water in the blood vessels leak out? Yes, but under normal circumstances, the internal and external pressures of blood vessels are in a dynamic equilibrium. This balance mainly depends on the colloid osmotic pressure, and the osmotic pressure formed by albumin, globulin, and fibrinogen in the plasma is the colloid osmotic pressure. , colloid osmotic pressure can change the fluid balance inside and outside the blood vessels. Once the albumin is too low, the colloid osmotic pressure decreases and the vascular permeability increases, and the water in the blood vessels will leak to the subcutaneous tissue outside the blood vessels through the space of the blood vessel wall. It accumulates under the skin, and there is a puffy edema that is pressed into a pit. This is called dystrophic edema.
Under normal circumstances, adult plasma albumin is about 35-55 g/L. When the patient’s plasma albumin is less than 35 g/L, hypoalbuminemia can be diagnosed. Hypoalbuminemia is very common in critically ill patients such as advanced cancer. The causes of hypoalbuminemia mainly include four aspects:
1. Insufficient intake
Inappetence and anorexia caused by various reasons in advanced cancer patients, malabsorption caused by congestion in the gastrointestinal tract, or obstruction of the digestive tract, and difficulty in eating, the three major nutrients that patients consume daily There is a serious shortage of substances, and there is not enough raw materials to synthesize enough albumin.
2. No output
The liver is the main organ for protein synthesis. Under normal conditions, approximately 0.2 g/kg of albumin is synthesized per day and then transported outside the liver by the intravenous system. When the disease causes liver damage, it will lead to a decrease in the ability of the liver to synthesize protein, and a decrease in plasma protein synthesis, resulting in a decrease in serum albumin levels. The vast majority of cancer patients with liver metastases will have varying degrees of hypoalbuminemia, which is related to the decreased synthesis capacity of the liver.
3. Loss and excessive consumption
Nausea, vomiting, diarrhea and other adverse reactions cause protein loss. In addition, tumor patients often experience ascites and pleural effusion, and repeated puncture and discharge will lead to a large loss of albumin. As a wasting disease, the catabolism of nutrients, including albumin, is accelerated in cancer patients, resulting in excessive consumption of nutrients.
4. Abnormal distribution
In the advanced stage of malignant tumor, capillary endothelial cells will be destroyed. At this time, the permeability of systemic capillaries increases, and intravascular albumin penetrates into the interstitial space, resulting in hypoalbuminemia.
What should I do if a patient with advanced cancer develops edema?
For edema caused by hypoalbuminemia, the main thing is to strengthen nutrition and supplement high-quality protein foods (fish and shrimp protein, etc.). For patients with loss of appetite, artificial homogenate meal and whey protein complete nutrition enteral nutrition can be given. Severe hypoalbuminemia combined with pleural and ascites and edema can be directly infused with albumin, and appropriate diuresis to reduce swelling. Generally speaking, it is recommended to supplement 8g of human serum albumin for every 1L of ascites drained.