Complications can be encountered with long-term hemodialysis

The article was professionally consulted by Specialist Doctor I Nguyen Hung - Endocrinologist - Department of Medical Examination & Internal Medicine - Vinmec Danang International Hospital

Patients with stage 5 chronic kidney failure need regular hemodialysis to help filter blood, clean waste, and remove excess water. However, during dialysis, many hemodialysis complications can occur.

Hemodialysis is a method of filtering blood outside the body, the patient's blood will be sucked into the dialysis machine to filter waste and excess water, after being cleaned, the blood will be returned to the patient's circulation. Hemodialysis is one of the methods of renal replacement therapy for patients with stage 5 chronic renal failure, that is, end stage chronic renal failure, when the glomerular filtration rate is ≤ 15ml/min/1.73 m2. Once hemodialysis is indicated, patients with chronic kidney failure will need to be on dialysis for the rest of their lives. Normally, patients will have dialysis 3 times a week, performed every other day, each dialysis takes place at least 4 hours.

2.1 Hypotension This is the most common complication of hemodialysis, the rate is 20-30% of patients. There are many causes of low blood pressure during hemodialysis such as:
Decrease or excessive increase in blood volume: Short duration of dialysis, patients gain a lot of weight between dialysis sessions, dry weight, calculated kilograms incorrect,... The filtrate temperature is higher than the patient's blood temperature, the patient's skin will expand to release heat. Vasodilation reduces vascular resistance, increasing the risk of hypotension. The patient eats while on dialysis. When eating, the amount of blood will flow to the veins of the digestive system, the amount of blood to the heart is poor, causing the risk of low blood pressure. The patient took antihypertensive drugs before dialysis. Patients with cardiovascular diseases such as heart failure, myocardial infarction, arrhythmia, ischemic heart disease, etc. In patients with cardiovascular disease, the compensatory mechanism in the heart is disturbed causing the risk of hypertension. Rare causes: Diaphragm allergy, thromboembolism, sepsis 2.2 Cramping is the second most common complication of hemodialysis after hypotension, the incidence is 5-20% of patients. Predisposing factors for cramps are:
Low blood pressure High weight gain Decreased circulating volume Low Na+ concentration in dialysis fluid Low concentration of Mg+, Ca++ in patient's blood before dialysis 2.3 Nausea and vomiting Occurs Occurs in 5-15% of patients on dialysis, the causes of nausea and vomiting are:
Hypotension Unbalance syndrome Reaction to the dialysis membrane Gastroparesis Contaminated dialysis or dialysis fluid has high concentrations of these substances. unsuitable substance. When the patient has nausea and vomiting, the patient's blood pressure must be checked, and antihypertensive treatment should be instituted, if any. Administer anti-nausea agents such as metoclopramide if necessary. Prevention of hypertension is the most important antiemetic measure.

2.4 Headache A complication of hemodialysis occurring in 5% of patients. The cause of the headache is unknown, but it may be a symptom of imbalance or other neurological causes. For patients addicted to coffee, when dialysis will quickly reduce the concentration of coffee in the blood, causing headaches.
2.5 Chest pain, back pain 2-5% of dialysis patients have mild chest pain with back pain. It is usually caused by first-time filter syndrome or myocardial ischemia. There is no specific treatment or prevention for this symptom. Closely monitor the patient and treat on a case-by-case basis.
2.6 Itching Itching is a common symptom in patients with renal failure. Causes of itching can be caused by:
Allergic to the filter membrane or some substances in the filtrate. Secondary hyperparathyroidism Deposits on the skin crystals of Mg2+, Ca2+, Phosphorus,... Drug or viral hepatitis 2.7 Unbalanced syndrome Usually occurs in patients who are elderly, have severe metabolic acidosis, or have previous brain damage. The disease has symptoms such as nausea, headache, restlessness, high blood pressure, disorientation, seizures, coma,...
When severe imbalance syndrome occurs, stop dialysis. , resuscitation to keep airway open, giving patients blood breathing, anti-epileptic treatment, high blood pressure,...