Perioperative management of kidney transplants

Preoperative management

Necessary labs

• Rapid-turnaround preoperative COVID screening should be performed immediately upon arrival
• Human leukocyte antigen (HLA) at time of transplant
• Comprehensive metabolic panel (CMP)
• Complete blood count (CBC) with differential
• Coagulation factors: prothrombin time (PT), partial thromboplastin time (PTT)/international normalized ratio (INR)
• If a
  hemodialysis (HD)
  catheter is in place, culture all lumens of the HD catheter
• If on
  peritoneal dialysis (PD)
  , collect dialysate fluid cell count, gram stain and culture
  • After sample is collected, connect PD catheter to drain bag and allow to drain to gravity
• Urinalysis (UA) and urine culture if able to collect a urine sample (e.g., not anuric/severely oliguric)
• Girls ≥12 years of age:
• Urine hCG if able to collect a urine sample (e.g., not anuric/severely oliguric), otherwise blood hCG
• Unless precluded by state laws, OPTN policies dictate that for patients ≥12 years of age the following labs must be sent after admission but before anastomosis of the graft:
  • Patients who are <12 years of age will have these labs drawn as part of their transplant evaluation process or while they are on the waiting list
  • HIV using a CDC recommended laboratory HIV testing algorithm
  • Hepatitis B virus (HBV): [PDF: CDC interpretation guide]
    • HBcAb: hepatitis B core antibody (total, IgG + IgM),
    • HBsAb: hepatitis B surface antibody (quantitative), and
    • HBsAg: hepatitis B surface antigen
  • Hepatitis C virus (HCV):
    • Anti-HCV antibody (IgG)
    • HCV ribonucleic acid (RNA) by nucleic acid test (NAT), quantitative

Dialysis plan

• If on
  hemodialysis (HD)
  or
  peritoneal dialysis (PD)
  , will they require a dialysis treatment prior to going to the OR?
  • Ensure that up-to-date information is available regarding their dialysis prescription
• Does this patient require intraoperative
  CKRT
  ?

Immunosuppression plan

• Induction immunosuppression?
  • Typically anti-thymocyte globulin, mycophenolate mofetil, and methylprednisolone
  • For patients who will be going promptly to the OR, mycophenolate mofetil (CellCept®) is generally given intravenously immediately after IV access is established
  • Is plasmapheresis required?
  • Do they require a dose of eculizumab?
• Maintenance immunosuppression: steroid free or steroid based?

Consent

• Consent should be obtained by the transplant surgery team
  • If a donor is classified as high/increased risk, then a “high risk consent” must be obtained from the patient/family by the transplant surgery team

Diet

• Patients should be made NPO on arrival (and are often instructed to be NPO prior to arrival to the hospital)

Fluid management

• Strict I&Os: all intakes and outputs should be closely measured
  • Careful ongoing assessment of fluid balance is essential to ensure appropriate hydration status before going to the OR
  • For some patients, this data can be used to determine whether a patient is actively polyuric
• Continuous intravenous fluids
  • If they are dehydrated and require resuscitation, consider a fluid bolus (10-20 mL/kg, up to 1 L) with 0.9% normal saline
  • D5-NS is often an appropriate choice
    • If a patient is polyuric, monitor closely to keep their fluid balance net positive
      • If they have a urinary concentrating defect, D5-0.45% (“half normal”) or D5-0.225% (“quarter normal”) saline may be a more appropriate fluid choice
    • If a patient is oliguric/anuric, target a fluid balance that slightly exceeds insensible losses to maintain a gentle positive fluid balance
      • Estimate insensible losses at 400 mL/m²/day, and divide over 24 hours to get the hourly fluid rate

Medication management

• Discontinue ACE inhibitors
• Target blood pressures on the high end of normal (around 90th percentile)
• Consider discontinuing other antihypertensives

Nephrectomy

Patients may need to have one or both of their native kidneys removed at time of transplant:

• Uncontrolled kidney-related hypertension
• Difficult to control kidney-related hypertension (i.e., requiring ≥3 agents)
• Polycystic kidney disease, especially in patients with a history of infected cysts or very large kidneys
• Polyuria to a degree that the recipient would have difficulty keeping up enough fluid intake to balance the urine lost from the transplanted kidney and native kidneys
• Severe vesicoureteral reflux and megaureter that is not amenable to repair
• Recent history of recurrent UTIs
• Need for space

Transplant surgery

• The kidney allograft is placed extraperitoneally in the right or left iliac fossa (typically on the right)
• The donor renal vessels are usually anastomosed to the external iliac vessels of the recipient, though this may vary
• Urinary reconstruction is almost always via uretero-neocystostomy (donor ureter is connected to recipient bladder), although at times other types of reconstruction can be chosen
• After anastomosis, the surgery team will be able to note the blood pressure at which the kidney appears well perfused and has robust urine output; this information will be useful in the postoperative period
• Initial function of the allograft is enhanced by:
  • Short cold ischemia time
  • Short rewarming (anastomosis) time
  • Intravascular volume repletion

Postoperative ICU management

Immediate postoperative care

• Maintenance IV fluids (0.9% NaCl, normal saline) to cover insensible losses
  • Based on body surface area: 400 mL/m²/day, divided by 24 to get the hourly rate
  • See: kidney.wiki BSA calculator
• Strict monitoring of intake/output
  • Urine output goal typically 50 mL/h
• Urine replacement with 0.45% NaCl or 0.9% NaCl for 24 hours
  • Typically 1:1 replacement, assessed every hour, with max of 200-500 mL/h
• Check serum electrolytes on arrival to the ICU, then every 6 hours
• Monitor CVP for first 24 hours
  • Goal typically >8, but the transplant surgeon will note what CVP was associated with good intraoperative urine output and may adjust the postoperative CVP goal accordingly
  • If needing intravascular volume repletion, bolus 10 mL/kg with 0.9% NaCl (normal saline)
    • Consider 10 mL/kg of 5% albumin (colloid)
  • [OpenPediatrics: Interpreting CVP Waveforms]
• Avoid hypotension: SBP goals typically ~120-140 mmHg
  • May adjust goal to 100-140 mmHg if younger and/or no history of hypotension, as long as perfusion continues to be good (i.e., urine output is stable)
  • Vasopressor of choice: dopamine
  • Oral options for BP augmentation are available: midodrine, fludrocortisone
• If fluid overloaded:
  • Reduce urine output replacement, or stop replacement fluids and transition to maintenance fluids