What causes shortness of breath (SOB) after dialysis?

From the Guidelines

Shortness of breath (SOB) after dialysis is commonly caused by fluid overload, ultrafiltration-induced hypotension, or dialysis disequilibrium syndrome, and the immediate management includes supplemental oxygen and positioning the patient upright, as recommended by recent guidelines 1. The management of SOB after dialysis involves a comprehensive approach, including:

• Supplemental oxygen (2-4 L/min via nasal cannula) and positioning the patient upright to improve oxygenation and reduce respiratory distress
• Reassessing the patient's dry weight and adjusting the ultrafiltration rate in future sessions to prevent fluid overload
• Administering IV fluids (250-500 mL normal saline) and temporarily reducing or pausing ultrafiltration if hypotension is present
• Slowing the blood flow rate and considering prophylactic mannitol (0.5-1.0 g/kg) before future sessions if dialysis disequilibrium syndrome is suspected Other potential causes of SOB after dialysis include cardiac issues (arrhythmias, heart failure), pulmonary embolism, or allergic reactions to dialyzer components, which require specific treatments. Prevention strategies include:
• Gradual ultrafiltration to prevent rapid changes in fluid status
• Sodium modeling to optimize fluid removal and prevent hypotension
• Careful dry weight assessment to prevent fluid overload Patients should be educated to report pre-dialysis symptoms like weight gain, edema, or increased shortness of breath, which may indicate fluid overload requiring adjustment to the dialysis prescription, as emphasized by recent studies 1.

From the Research

Causes of Shortness of Breath after Dialysis

• Shortness of breath (SOB) after dialysis can be caused by various factors, including underlying chronic lung disease, fluid overload, and anemia 2, 3.
• Haemodialysis itself can worsen breathlessness, particularly if the patient is not in chronic fluid overload and the symptoms improve after termination of haemodialysis 2.
• The bicarbonate concentration in the dialysis fluid may also play a role in the development of shortness of breath and hypoxemia during haemodiafiltration (HDF) treatments 4.

Pathophysiology of Dyspnea in Chronic Kidney Disease

• Dyspnea is a common symptom in chronic kidney disease (CKD) patients and has a profound influence on their quality of life 3.
• The pathophysiology of dyspnea in CKD is complex and multifactorial, involving factors such as congestive heart failure, unrecognized chronic lung disease, pulmonary hypertension, and systemic inflammation 3.
• Anemia is also a potential cause of breathing disorders in CKD patients, and treatment with erythropoiesis-stimulating agents (ESAs) may be affected by inflammation 5, 6.

Treatment and Management

• Supplemental oxygen during haemodialysis may improve symptoms of shortness of breath, but shortening the dialysis duration may also be necessary in some cases 2.
• Adjusting the bicarbonate concentration in the dialysis fluid may help alleviate symptoms of shortness of breath during HDF treatments 4.
• Treatment of anemia with ESAs and iron supplements is crucial in managing dyspnea in CKD patients, but inflammation may reduce the response to ESA treatment 5, 6.