NMS. Casos Clínicos

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Chapter 1 ♦ Preoperative Care

Case 1.8  Surgery in a Patient with Chronic Kidney Problems A 52-year-old woman with aseptic necrosis of her right leg requires hip replacement. His history is significant for chronic renal failure for 10 years secondary to glomer- ulonephritis. Initial management involved a kidney transplant from a living relative and immunosuppression with cyclosporine and prednisone . Recently, the patient has experienced progressive chronic rejection and has a creatinine of 3.5 mg/dL. On physical examination, multiple stigmata of steroid management, including striae, moon facies, and easy bruisability, are evident. The patient has mild ankle edema. The patient experiences pain on passive motion of the right hip. Q: Would you recommend proceeding with the hip replacement at this time? A: The decision regarding the timing of hip replacement surgery is best made in conjunction with an orthopedist who is experienced in treating patients with renal problems. In patients with progressive deteriorating renal function, repair of the hip should be delayed until the transplant function has stabilized or the necessary dialysis has begun. Once a patient’s renal status is stable, the hip can be reassessed and a plan determined. Repairing the hip during transplant deterioration may complicate or aggravate the rejection process and hasten the need for dialysis. Q: How would you prepare the patient for surgery? A: The major objective is to resolve any correctable problems before taking a patient with chronic renal failure to the operating room. Thus, dialysis immediately before surgery is desirable. Transplant patients should be adequately hydrated and have well-controlled BP. Infection control is desirable in both types of patients. Many of these patients also have been on steroids in the recent past. If so, the preoperative dosage should be continued, and stress doses of hydrocortisone can be given if needed. Well-dialyzed patients have the most normalized platelet function, hydration state, BP control, and electro- lyte status.

Preoperative laboratory tests from 2 days ago reveal a serum potassium of 5.1 mEq/L, and the patient is in the holding area ready for the operating room. Q: Is a 2-day-old potassium value an adequate preoperative measurement? A: This measurement is too old to rely on for surgery because the potassium can rise to dan- gerous levels in short periods of time in chronic renal failure. A repeat potassium level needs to be obtained immediately—before the patient proceeds to the operating room. You decide to proceed with surgery and encounter intraoperative bleeding due to a “capillary ooze.” Q: How would you manage the bleeding? A: Platelet dysfunction due to uremia can contribute to intraoperative bleed- ing. Transfusion of platelets will not help. Correcting the uremia will help. Several substances can be used to improve platelet function. Desmopressin (ddAVP) may be used acutely. It has a rapid effect of short duration and may induce tachyphylaxis (loss of hemostatic effect with multiple doses); its action is related to release of von Willebrand SAMPLE