What assessments should be performed before initiating in‑center hemodialysis?

Pre-Hemodialysis Patient Assessment

Before initiating hemodialysis, assess vascular access patency, volume status, vital signs (especially blood pressure), and review laboratory parameters including baseline BUN for adequacy monitoring, while screening for hepatitis C and evaluating cardiac function with ECG and echocardiography. 1, 2

Vascular Access Evaluation

Assess the access site for patency and signs of infection or complications at every session. 2 This is critical because access dysfunction is a leading cause of inadequate dialysis delivery.

• Examine arteriovenous fistula or graft integrity to determine if recirculation may be present using hydraulic compression testing. 1, 2
• Review A/V needle placement, proximity, and orientation with patient care staff to optimize blood flow and minimize recirculation. 1, 2
• Verify graft flow configuration to ensure proper access function. 1
• For catheter access, examine the exit site for signs of infection after performing hand hygiene. 3

Volume Status and Hemodynamic Assessment

Evaluate for signs of volume overload or dehydration as achieving euvolemia is fundamental to successful dialysis and preventing complications. 1, 2

• Measure blood pressure, but do not rely solely on pre-dialysis readings as they are imprecise estimates of interdialytic blood pressure. 2
• Document baseline weight and compare to target dry weight to guide ultrafiltration goals. 2
• Assess for peripheral edema, jugular venous distension, and pulmonary congestion as markers of volume overload. 1

Laboratory Baseline Assessment

Obtain predialysis BUN sample immediately before dialysis using a technique that avoids dilution with saline or heparin. 1, 2, 3 This establishes baseline for adequacy monitoring.

• Draw the specimen from the arterial needle prior to connecting arterial blood tubing or flushing the needle when using AV fistula/graft. 1
• For venous catheters, withdraw any heparin and saline from the arterial port following unit protocol, then withdraw 10 mL of blood (3-5 mL for pediatrics) before obtaining the sample. 1
• Measure baseline hemoglobin using predialysis samples, as it is more stable and accurate than hematocrit. 4, 3
• Check serum ferritin and transferrin saturation to establish iron status before initiating erythropoiesis-stimulating agents. 4, 3
• Measure electrolytes including sodium, potassium, calcium, phosphorus, magnesium, and bicarbonate to identify metabolic derangements requiring correction. 4, 3
• Obtain serum albumin as a baseline marker of nutritional status and mortality predictor. 4, 3

Infection Screening

Screen all incident hemodialysis patients for hepatitis B and C before admission to the outpatient dialysis facility. 1, 3

• Test for HBsAg, anti-HBs, and anti-HBc to determine hepatitis B status and vaccination needs. 3
• Screen for hepatitis C using anti-HCV antibody with confirmation by nucleic acid testing (NAT) if positive. 1
• In high HCV prevalence units, consider initial testing with NAT as HCV-RNA can be positive in 10% of anti-HCV-negative patients during the window period. 1
• Draw NAT samples before dialysis because hemodialysis reduces viremia levels. 1
• Obtain baseline serum ALT level for monthly monitoring to detect acute HCV infection, which has 83% sensitivity and 90% specificity. 1, 3

Cardiac Evaluation

Obtain baseline 12-lead ECG and echocardiogram within 1-3 months after achieving dry weight to assess for left ventricular hypertrophy, systolic dysfunction, and diastolic dysfunction. 1, 4, 3

• Perform echocardiography once patients have achieved dry weight (ideally within 1-3 months of dialysis initiation) as the prevalence of systolic or diastolic dysfunction or overt LVH is at least 75% at dialysis initiation. 1
• Evaluate for cardiomyopathy as patients with significant reduction in LV systolic function (EF <40%) should be evaluated for coronary artery disease. 1
• Plan for annual ECGs after dialysis initiation for ongoing cardiac surveillance. 4, 3

Clinical Status Review

Review the patient's clinical status including vital signs with special attention to symptoms of uremia, protein-energy wasting, and ability to manage metabolic abnormalities. 1, 2, 3

• Assess for uremic symptoms including nausea, vomiting, altered mental status, pericarditis, or bleeding diathesis that indicate need for dialysis initiation. 1
• Evaluate for protein-energy wasting as this influences the decision to initiate dialysis independent of GFR level. 1
• Document any history of heart failure, low serum albumin, elevated BUN/creatinine ratio, or hyperuricemia as these predict need for dialysis at higher GFR levels and may require earlier vascular access creation. 5

Treatment Parameters Documentation

Review and document prescribed treatment parameters including dialyzer type, blood flow rate (Qb), dialysate flow rate (Qd), and treatment duration. 1, 2

• Check dialysis machine maintenance log for last calibration date and results to ensure equipment accuracy. 1
• Verify prescribed versus actual parameters to establish baseline for adequacy monitoring. 1
• Document extracorporeal pressures to compare with subsequent sessions and identify access problems. 1, 2, 3

Common Pitfalls to Avoid

Do not draw predialysis BUN samples after hemodialysis has been initiated or if saline/heparin is present in the lines, as this causes sample dilution and falsely low Kt/V calculations. 1

Avoid relying solely on eGFR to determine dialysis initiation timing, as the decision should be based primarily on uremic symptoms, protein-energy wasting, and inability to manage metabolic abnormalities rather than a specific GFR threshold. 1 Patients with heart failure, hypoalbuminemia, high BUN/Cr ratio, or hyperuricemia often require dialysis at higher GFR levels and need earlier preparation. 5