Outcomes of combined cardiac surgery and kidney transplant compared with kidney transplant after cardiac surgery Context—Patients with chronic renal failure have a high prevalence of coronary artery disease and cardiovascular death. The mortality and the morbidity rates of cardiac surgery are particularly high in these patients with end-stage renal disease. Performing cardiac surgery and kidney transplant in the same session can reduce these complications in the early postoperative period by normalizing renal function. Objective—To compare the mortality and morbidity rates between patients who had undergone cardiac surgery and kidney transplant separately and patients who had combined surgeries. Methods—This retrospective study consisted of 75 patients. One group of 60 patients underwent cardiac surgery and kidney transplant in separate sessions, and the other group of 15 patients had combined surgeries in the same session, between March 2008 and September 2012. Results—Patients who had combined surgeries achieved fluid electrolytic balance more easily, had shorter extubation times, used less blood and blood products, and had fewer major complications. The patients recovered faster and thus had shorter stays in the intensive care unit and hospital. This combined surgical approach allows normalized kidney function in patients with end-stage renal disease, so mortality and morbidity in the early postoperative period could be significantly reduced. (Progress in Transplantation. 2014;24:349-354) ©2014 NATCO, The Organization for Transplant Professionals doi: http://dx.doi.org/10.7182/pit2014806
T
he prevalence of cardiovascular disease in patients with end-stage renal disease is 40% to 52% higher than in patients with no renal disease, and cardiovascular disease is the leading cause of mortality in these patients.1-3 Presence of common risk factors such as hypertension and type 2 diabetes mellitus makes patients with end-stage renal disease more prone to cardiac events. Coronary atherosclerosis and left ventricular dysfunction are the most commonly seen cardiovascular abnormalities.4 In order to prevent cardiovascular death after transplant, cardiac screening of patients has been recommended.5 Thus, because patients with endstage renal disease are at high risk for cardiac events, revascularization of coronary stenosis has been recommended before transplant. On the other hand, coronary revascularization in these patients is associated with
Progress in Transplantation, Vol 24, No. 4, December 2014
Mehdi Zengin, PhD, Murat Bulent Rabus, MD, Sabri Tekin, MD, Levent Yucetin, MD, Alper Demirbas, MD, Omer Bayezid, MD Medicalpark Antalya Hospital (MZ, ST, LY, AD) and Akdeniz University School of Medicine (OB), Antalya, Turkey, Kosuyolu Heart Training and Research Hospital, Istanbul, Turkey (MBR) Corresponding author: Mehdi Zengin, PhD, Heart and Vascular Surgery Clinic, Medicalpark Antalya Hospital, Fener Mh, Tekelioglu Cd. No. 7, Lara, Antalya, Turkey (e-mail: [email protected]) To purchase electronic or print reprints, contact: American Association of Critical-Care Nurses 101 Columbia, Aliso Viejo, CA 92656 Phone (800) 899-1712 (ext 532) or (949) 448-7370 (ext 532) Fax (949) 362-2049 E-mail [email protected]
an in-hospital mortality 3.1 times greater for dialysis patients than for patients who do not require renal replacement therapy.6 In this retrospective study, we present the results of combined heart surgery and kidney transplant performed in the same session and compare the mortality and morbidity rates between those patients and patients who had undergone cardiac surgery and kidney transplant separately. Methods Seventy-five patients with end-stage renal disease who were awaiting a transplant and had coronary artery disease diagnosed after cardiac screening tests in our clinic between March 2008 and September 2012 were analyzed retrospectively and were included in the study.
349
Zengin et al The patients were arranged into 2 groups. The separate surgeries group consisted of 60 patients who had cardiac surgery at first and then had kidney transplant surgery in the following 1 to 6 months. The combined surgeries group consisted of 15 patients who underwent both surgeries in the same session. Patients in the combined surgeries group received kidney transplants from living donors. No deceased donor had been used. Renal function in the donors was evaluated on the basis of their creatinine clearance, 24-hour proteinuria, and ultrasound imaging of the kidneys. Special tests that involve blood type incompatibility, paired exchange, and positive cross-matching had been done. Serologic tests were done; patients testing positive for infection with hepatitis B virus, hepatitis C virus, or cytomegalovirus were considered for liver biopsy before transplant. All procedures had been described to the patients in detail by the surgeon before the surgery, and informed consent had been obtained from the patients. Preoperative Characteristics of Patients The mean (SD) age of patients in the separate surgeries group was 52.2 (8.6) years (Table 1). Most of the patients had hypertension (67%) or type 2 diabetes (65%). Eight (13%) of the patients had severe left ventricular function (ejection fraction .99
Cardiopulmonary bypass time, mean (SD), min
58 (16)
55 (11)
.50
42 (6)
41 (8)
.59
3.2
3.1
>.99
18 (4)
19 (7)
.47
Aortic valve replacement
0 (0)
0 (0)
Cross-clamp time, mean (SD), min
Mitral valve replacement
2 (3)
1 (7)
Number of vessels, mean (SD)
Coronary artery bypass grafting + mitral valve replacement
1 (2)
0 (0)
Coronary artery bypass grafting + aortic valve replacement
Hematocrit during cardiopulmonary bypass, mean (SD), %
1 (2)
0 (0)
Right atrial myxoma
0 (0)
1 (7)
P
control visits were called by phone and information was received. bypass. The left internal mammary artery was prepared and used for all patients who had coronary surgery. The hematocrit levels were similar in both groups. Postoperative Period (First 48 Hours After Surgery) Inotropic supports such as dobutamine, epinephrine, and/or dopamine were used routinely in the early postoperative period to stabilize the hemodynamics. Diuretics were added if necessary to have adequate diuresis. All patients’ creatinine clearance and their creatinine, serum urea nitrogen, urea, and electrolyte levels were monitored. If deemed necessary, hemodialysis was performed on the patients who did not have combined surgeries after consultation with a nephrologist about fluid volume and potassium levels. Patients’ kidney function was assessed periodically after surgery. Nephrotoxic medications such as angiotensin receptor inhibitors were prohibited. Cefazolin was used for prophylaxis for infections. Subcutaneous heparin was used if no gross drainage (>300 mL/h) was apparent, and leg stockings were used to prevent deep venous thrombosis of the lower limbs. Marked attention was paid to wound and patient care. Immunosuppressive Treatment One day before the kidney transplant surgery, oral immunosuppressive treatment (prednisolone + tacrolimus + azathioprine) was started in all patients. A high dose of steroid was given during the operation. On following days, the appropriate doses were adjusted according to serum levels of the drugs. If acute kidney failure was suspected because of decreased diuresis, immunosuppressive treatment was intensified. Long-Term Follow-up After discharge, patients were followed up by both the cardiac surgery service and the organ transplant service for 2 years. The patients who did not attend
Progress in Transplantation, Vol 24, No. 4, December 2014
Statistical Analysis All of the data were analyzed with SPSS for Windows 11.5. Descriptive statistics for continuing variables were shown as mean (SD) and nominal variables were shown as number of cases (n) and percentage. The significance of the differences between groups was assessed by using a Student t test. Nominal variables were analyzed with a Pearson χ2 test or a Fisher exact χ2 test. A P value less than .05 was considered significant. Results In-Hospital Mortality The overall early (30-day) mortality rate was 5% in the separate surgeries group (3 of 60 patients), and zero in the combined surgeries group. Three of the patients from the separate surgeries group died while in the hospital after the surgery. One of these patients was a 31-year-old woman being treated with insulin for type 2 diabetes; her ejection fraction was 42% and she had undergone CABG and mitral valve replacement. She had been dependent on dialysis for 8 years. Intense inotropic support and intra-aortic balloon support were achieved before cardiopulmonary perfusion was ended. Hypotension and metabolic acidosis developed in the postoperative intensive care unit. The second patient was a 60-year-old man who had type 2 diabetes, hypertension, and mid-left ventricular dysfunction (ejection fraction, 40%). During the surgery, it was observed that he had thin vessels and a diffuse atherosclerosis inside the coronary arteries. The third patient was a 65-year-old woman who had hypertension, hypercholesterolemia, and a history of transient ischemic attack. She had CABG of 3 coronary arteries. She was taken to the intensive care unit with inotropic support. Metabolic acidosis and fluid retention developed. Effective dialysis could not be performed. The
351
Zengin et al Table 4 Postoperative characteristics
Variable Early mortality, No. (%) Blood transfusions, mean (SD), units Erythrocyte suspension Plasma Thrombocyte Whole blood
Table 5 Hemodynamic and metabolic parameters
Separate Combined surgeries surgeries (n = 60) (n = 15) 3 (5)
5.8 (4.5) 7.4 (2.4) 1.1 (0.4) 3.8 (0.8)
0 (0)
P >.99
4.2 (2.7) .19 4.8 (2.1)
T
he prevalence of cardiovascular disease in patients with end-stage renal disease is 40% to 52% higher than in patients with no renal disease, and cardiovascular disease is the leading cause of mortality in these patients.1-3 Presence of common risk factors such as hypertension and type 2 diabetes mellitus makes patients with end-stage renal disease more prone to cardiac events. Coronary atherosclerosis and left ventricular dysfunction are the most commonly seen cardiovascular abnormalities.4 In order to prevent cardiovascular death after transplant, cardiac screening of patients has been recommended.5 Thus, because patients with endstage renal disease are at high risk for cardiac events, revascularization of coronary stenosis has been recommended before transplant. On the other hand, coronary revascularization in these patients is associated with
Progress in Transplantation, Vol 24, No. 4, December 2014
Mehdi Zengin, PhD, Murat Bulent Rabus, MD, Sabri Tekin, MD, Levent Yucetin, MD, Alper Demirbas, MD, Omer Bayezid, MD Medicalpark Antalya Hospital (MZ, ST, LY, AD) and Akdeniz University School of Medicine (OB), Antalya, Turkey, Kosuyolu Heart Training and Research Hospital, Istanbul, Turkey (MBR) Corresponding author: Mehdi Zengin, PhD, Heart and Vascular Surgery Clinic, Medicalpark Antalya Hospital, Fener Mh, Tekelioglu Cd. No. 7, Lara, Antalya, Turkey (e-mail: [email protected]) To purchase electronic or print reprints, contact: American Association of Critical-Care Nurses 101 Columbia, Aliso Viejo, CA 92656 Phone (800) 899-1712 (ext 532) or (949) 448-7370 (ext 532) Fax (949) 362-2049 E-mail [email protected]
an in-hospital mortality 3.1 times greater for dialysis patients than for patients who do not require renal replacement therapy.6 In this retrospective study, we present the results of combined heart surgery and kidney transplant performed in the same session and compare the mortality and morbidity rates between those patients and patients who had undergone cardiac surgery and kidney transplant separately. Methods Seventy-five patients with end-stage renal disease who were awaiting a transplant and had coronary artery disease diagnosed after cardiac screening tests in our clinic between March 2008 and September 2012 were analyzed retrospectively and were included in the study.
349
Zengin et al The patients were arranged into 2 groups. The separate surgeries group consisted of 60 patients who had cardiac surgery at first and then had kidney transplant surgery in the following 1 to 6 months. The combined surgeries group consisted of 15 patients who underwent both surgeries in the same session. Patients in the combined surgeries group received kidney transplants from living donors. No deceased donor had been used. Renal function in the donors was evaluated on the basis of their creatinine clearance, 24-hour proteinuria, and ultrasound imaging of the kidneys. Special tests that involve blood type incompatibility, paired exchange, and positive cross-matching had been done. Serologic tests were done; patients testing positive for infection with hepatitis B virus, hepatitis C virus, or cytomegalovirus were considered for liver biopsy before transplant. All procedures had been described to the patients in detail by the surgeon before the surgery, and informed consent had been obtained from the patients. Preoperative Characteristics of Patients The mean (SD) age of patients in the separate surgeries group was 52.2 (8.6) years (Table 1). Most of the patients had hypertension (67%) or type 2 diabetes (65%). Eight (13%) of the patients had severe left ventricular function (ejection fraction .99
Cardiopulmonary bypass time, mean (SD), min
58 (16)
55 (11)
.50
42 (6)
41 (8)
.59
3.2
3.1
>.99
18 (4)
19 (7)
.47
Aortic valve replacement
0 (0)
0 (0)
Cross-clamp time, mean (SD), min
Mitral valve replacement
2 (3)
1 (7)
Number of vessels, mean (SD)
Coronary artery bypass grafting + mitral valve replacement
1 (2)
0 (0)
Coronary artery bypass grafting + aortic valve replacement
Hematocrit during cardiopulmonary bypass, mean (SD), %
1 (2)
0 (0)
Right atrial myxoma
0 (0)
1 (7)
P
control visits were called by phone and information was received. bypass. The left internal mammary artery was prepared and used for all patients who had coronary surgery. The hematocrit levels were similar in both groups. Postoperative Period (First 48 Hours After Surgery) Inotropic supports such as dobutamine, epinephrine, and/or dopamine were used routinely in the early postoperative period to stabilize the hemodynamics. Diuretics were added if necessary to have adequate diuresis. All patients’ creatinine clearance and their creatinine, serum urea nitrogen, urea, and electrolyte levels were monitored. If deemed necessary, hemodialysis was performed on the patients who did not have combined surgeries after consultation with a nephrologist about fluid volume and potassium levels. Patients’ kidney function was assessed periodically after surgery. Nephrotoxic medications such as angiotensin receptor inhibitors were prohibited. Cefazolin was used for prophylaxis for infections. Subcutaneous heparin was used if no gross drainage (>300 mL/h) was apparent, and leg stockings were used to prevent deep venous thrombosis of the lower limbs. Marked attention was paid to wound and patient care. Immunosuppressive Treatment One day before the kidney transplant surgery, oral immunosuppressive treatment (prednisolone + tacrolimus + azathioprine) was started in all patients. A high dose of steroid was given during the operation. On following days, the appropriate doses were adjusted according to serum levels of the drugs. If acute kidney failure was suspected because of decreased diuresis, immunosuppressive treatment was intensified. Long-Term Follow-up After discharge, patients were followed up by both the cardiac surgery service and the organ transplant service for 2 years. The patients who did not attend
Progress in Transplantation, Vol 24, No. 4, December 2014
Statistical Analysis All of the data were analyzed with SPSS for Windows 11.5. Descriptive statistics for continuing variables were shown as mean (SD) and nominal variables were shown as number of cases (n) and percentage. The significance of the differences between groups was assessed by using a Student t test. Nominal variables were analyzed with a Pearson χ2 test or a Fisher exact χ2 test. A P value less than .05 was considered significant. Results In-Hospital Mortality The overall early (30-day) mortality rate was 5% in the separate surgeries group (3 of 60 patients), and zero in the combined surgeries group. Three of the patients from the separate surgeries group died while in the hospital after the surgery. One of these patients was a 31-year-old woman being treated with insulin for type 2 diabetes; her ejection fraction was 42% and she had undergone CABG and mitral valve replacement. She had been dependent on dialysis for 8 years. Intense inotropic support and intra-aortic balloon support were achieved before cardiopulmonary perfusion was ended. Hypotension and metabolic acidosis developed in the postoperative intensive care unit. The second patient was a 60-year-old man who had type 2 diabetes, hypertension, and mid-left ventricular dysfunction (ejection fraction, 40%). During the surgery, it was observed that he had thin vessels and a diffuse atherosclerosis inside the coronary arteries. The third patient was a 65-year-old woman who had hypertension, hypercholesterolemia, and a history of transient ischemic attack. She had CABG of 3 coronary arteries. She was taken to the intensive care unit with inotropic support. Metabolic acidosis and fluid retention developed. Effective dialysis could not be performed. The
351
Zengin et al Table 4 Postoperative characteristics
Variable Early mortality, No. (%) Blood transfusions, mean (SD), units Erythrocyte suspension Plasma Thrombocyte Whole blood
Table 5 Hemodynamic and metabolic parameters
Separate Combined surgeries surgeries (n = 60) (n = 15) 3 (5)
5.8 (4.5) 7.4 (2.4) 1.1 (0.4) 3.8 (0.8)
0 (0)
P >.99
4.2 (2.7) .19 4.8 (2.1)
