CCHT Dialysis Procedures 2 — Questions and Answers
Question 1: What is the correct sequence for initiating hemodialysis using a central venous catheter (CVC)?
- Connect blood lines, then remove caps and aspirate clots
- Clamp lines, remove caps aseptically, aspirate and discard blood/heparin, then connect blood lines (Correct answer)
- Open the catheter, flush with saline, then connect without aspiration
- Remove the dressing, clean the site, then attach blood lines directly
Correct answer: Clamp lines, remove caps aseptically, aspirate and discard blood/heparin, then connect blood lines
CVC initiation requires clamping lines, aseptic cap removal, aspiration of the heparin lock and any clots, then connection of blood lines to prevent air entry and catheter-related infections.
The proper CVC connection procedure: apply mask and sterile gloves, clamp catheter lumens, remove old caps aseptically, clean hubs with chlorhexidine or alcohol, aspirate 3 to 5 mL from each lumen and discard (removes heparin lock and any clot), check for blood return, connect blood lines, unclamp and initiate treatment. Strict aseptic technique is mandatory to prevent catheter-related bloodstream infections.
Question 2: A patient develops muscle cramps during hemodialysis. What is the most appropriate initial intervention?
- Discontinue treatment immediately
- Reduce ultrafiltration rate and administer a small normal saline bolus (Correct answer)
- Increase blood pump speed
- Apply heat packs to the affected muscles
Correct answer: Reduce ultrafiltration rate and administer a small normal saline bolus
Muscle cramps during dialysis are usually caused by excessive fluid removal or low plasma osmolality; reducing the UF rate and giving a small saline bolus corrects fluid shifts.
Dialysis-associated muscle cramps typically occur due to rapid UF (intravascular volume depletion), hypotension, electrolyte shifts (hyponatremia), or hypo-osmolality. Initial management: reduce or stop UF, give 100 to 200 mL normal saline bolus, and reduce blood flow rate if hypotensive. Prevention includes reassessing dry weight, reducing UF rate, or using sodium modeling.
Question 3: What is the recommended approach when a patient's arterial pressure alarm activates with a very negative reading (e.g., -250 mmHg)?
- Ignore it if the patient feels fine
- Reduce the blood pump speed and check for arterial access problems (Correct answer)
- Increase the blood pump speed to overcome the resistance
- Stop treatment and remove the patient immediately
Correct answer: Reduce the blood pump speed and check for arterial access problems
Extremely negative arterial pressure indicates inadequate blood flow from the access; reducing pump speed and assessing the arterial needle or access helps identify and correct the problem.
Normal arterial (pre-pump) pressure should be slightly negative (-50 to -150 mmHg). Excessively negative pressure (-250 mmHg or more) indicates inadequate blood delivery: the needle may be against the vessel wall, the access is stenotic, the patient has low blood pressure, or the needle is malpositioned. Increasing pump speed worsens the problem by increasing suction.
Question 4: How should a hemodialysis treatment be terminated at the end of a session using the saline rinse-back method?
- Stop the pump and clamp all lines simultaneously
- Connect saline to the arterial line, rinse blood back to the patient, then remove needles (Correct answer)
- Remove needles first, then drain blood from the circuit
- Stop the blood pump and leave lines attached until blood clots
Correct answer: Connect saline to the arterial line, rinse blood back to the patient, then remove needles
Saline rinse-back connects saline to the arterial port, uses the blood pump to push remaining blood back to the patient, then lines are clamped and needles removed.
The rinse-back procedure returns approximately 100 to 200 mL of blood to the patient: clamp the arterial blood line and connect saline, restart pump at reduced speed, watch blood return through venous line, clamp venous line when saline is visible, stop pump. Then remove needles and apply pressure for hemostasis. Returning blood to the patient prevents unnecessary blood loss and anemia.
Question 5: What is the purpose of recirculation assessment during hemodialysis, and when would it occur?
- Recirculation is normal and indicates the fistula is working
- It occurs when returned blood immediately re-enters the arterial needle, reducing treatment efficiency (Correct answer)
- Recirculation means the dialyzer is removing too much waste
- It is a technique to improve clearance of large molecules
Correct answer: It occurs when returned blood immediately re-enters the arterial needle, reducing treatment efficiency
Access recirculation occurs when already-dialyzed blood from the venous needle re-enters the arterial needle, reducing treatment efficacy by diluting the blood being presented to the dialyzer.
Normal recirculation should be less than 5%. High recirculation can occur due to reversed needle placement, needles too close together, or access dysfunction. It significantly reduces dialysis adequacy. Diagnosed by sampling blood from the arterial line during treatment and comparing BUN to peripheral blood. Treatment may require needle repositioning or access intervention.
Question 6: During needle removal after hemodialysis, what is the correct method to achieve hemostasis at the needle sites?
- Apply a tourniquet above the access site
- Apply firm digital pressure with gauze for 5 to 10 minutes without releasing (Correct answer)
- Use sutures to close the needle site
- Apply ice immediately to constrict blood vessels
Correct answer: Apply firm digital pressure with gauze for 5 to 10 minutes without releasing
Firm, continuous digital pressure on the needle sites for 5 to 10 minutes (or until bleeding stops) achieves hemostasis without disrupting clot formation.
After needle removal, apply sterile gauze and maintain firm continuous pressure for 5 to 10 minutes (longer for patients on anticoagulation or with clotting disorders). Do not peek as releasing pressure disrupts clot formation. Avoid proximal compression (no tourniquets) as it increases venous pressure and promotes bleeding. Once hemostasis is achieved, apply a small bandage.
CCHT Dialysis Procedures 2
What is the correct sequence for initiating hemodialysis using a central venous catheter (CVC)?