Laparoscopic partial nephrectomy in cold ischemia: renal artery perfusion

PURPOSE: Laparoscopic partial nephrectomy represents a feasible option for patients with small renal masses. We describe our initial experience with laparoscopic partial nephrectomy in cold ischemia achieved by renal artery perfusion. MATERIALS AND METHODS: From November 2001 to March 2003 laparoscopic partial nephrectomy in cold ischemia was performed in 15 patients with renal cell carcinoma. Cold ischemia was achieved by continuous perfusion of Ringers lactate at 4C through the renal artery, which was clamped. Tumor excision was performed in a bloodless field with biopsy taken from the tumor bed. The collecting system was repaired if needed. Renal reconstruction was performed by suturing over hemostatic bolsters. RESULTS: All procedures were successfully completed laparoscopically by our new technique. Mean operative time was 185 minutes (range 135 to 220). Mean ischemia time was 40 minutes (range 27 to 101). Estimated mean intraoperative blood loss was 160 ml (range 30 to 650). Entry to the collecting system in 6 patients was repaired intraoperatively. Additional vascular repair was done in 2 patients. There were no significant postoperative complications. Postoperative followup in 8 patients showed that the renal parenchyma was not damaged by the ischemic period. CONCLUSIONS: Our initial experience of incorporating cold ischemia via arterial perfusion into laparoscopic partial nephrectomy shows the feasibility and safety of the technique. We believe that this approach has the potential to make laparoscopic partial nephrectomy for renal cell carcinoma safe and reliable.     

Hypothermic renal protection using cold histidine-tryptophan-ketoglutarate solution perfusion in suprarenal aortic surgery

We examined data of 21 patients who were treated with selective perfusion of both renal arteries with 500 mL of 8 degrees C histidine-tryptophan-ketoglutarate (HTK) solution each for renal protection during aortic surgery. Only the data from aortic surgeries with unavoidable suprarenal aortic cross-clamping for juxtarenal or suprarenal abdominal aortic aneurysms (AAAs) or high Leriche syndrome accompanied with stenosis of renal arteries are presented. Five patients underwent immediate surgery because of perforation of an AAA; the other 16 patients went through elective surgeries. In three cases (14%) stenosis of the renal arteries was diagnosed; nevertheless, implantation of an aortorenal bypass was necessary in seven patients. In total, 14 aortorenal bypasses were implanted (five venous grafts and nine prosthesis grafts). Four (19%) patients needed catecholaminergic support to establish stable circulatory conditions; in two (9%) of these cases additional ischemia of the colon was observed and sigmoidectomy was performed. All of these four patients underwent immediate surgery, and one died after surgery because of severe sepsis. In four cases postsurgical renal insufficiency was observed. Three of these patients were admitted for emergency surgery because of their hemodynamic situation due to perforation of the AAA. None of the patients needed chronic dialysis after surgery. Whereas in all patients who underwent elective surgery the renal function remained stable as judged by postoperative serum creatinine values, in five out of seven patients with aortorenal bypass surgery the renal function improved. Perfusion with cold HTK solution offers an additional procedure to protect renal function in patients undergoing elective surgery with suprarenal cross-clamping of the aorta.     

Aortic arch repair with right brachial artery perfusion

Background. To determine the effectiveness of unilateral selective cerebral perfusion for aortic arch repair and to discuss possible modifications to enhance technical simplicity.

Methods. In the period between January 1996 and April 2001, 104 patients underwent aortic arch repair with the use of right brachial artery low flow (8 to 10 mL/kg per minute) antegrade selective cerebral perfusion under moderate hypothermia (26°C). Mean patient age was 52 ± 12 years. Sixty-four patients presented with Stanford type A aortic dissection, including 12 with acute dissection; 38 patients had aneurysmal dilatation of the ascending aorta and aortic arch; and 2 patients had isolated arch aneurysm. Ascending and partial arch replacement was performed in 50 patients; ascending and total arch replacement in 33 patients; ascending and descending arch replacement in 19 patients; and isolated arch replacement in 2 patients.

Results. Mean antegrade cerebral perfusion time was 39 ± 22 minutes. One patient with acute proximal dissection died because of cerebral complications. One other patient developed right hemiparesis, which resolved during the second postoperative month without sequela. Other than these 2 cases (1.9%), no other neurologic event was observed.

Conclusions. The technique of low flow antegrade selective cerebral perfusion through the right brachial artery may be used for a vast majority of aortic aneurysms and dissections requiring arch repair. This technique does not necessitate deep hypothermia, requires shorter cardiopulmonary bypass and operation times, has the advantage of simplicity, provides optimal vascular repair without time restraints and, in terms of clinical results, is as safe as other techniques for cerebral protection.     

Myocardial protection by intermittent perfusion with cardioplegic solution versus intermittent coronary perfusion with cold blood

The myocardial protection provided by cardioplegic solution using buffered, isosmotic potassium (30 mEq. per liter) was compared with intermittent cold coronary perfusion for 2 hours of aortic cross-clamping in dogs. The cardioplegic solution (Group CS) or cold blood (Group CB) was infused every 15 minutes through a cooling coil to reduce the perfusate temperature to 5 degrees C. Myocardial function after 30 minutes of reperfusion and rewarming was reduced in Group CB with a significant reduction in peak systolic pressure at a left ventricular (LV) balloon volume of 20 ml. and a significant reduction of dp/dt. In contrast, in Group CS, LV function was unchanged from the base-line period. LV compliance also was significantly reduced in Group CB while being unchanged in Group CS. Myocardial extravascular water content, obtained by dessication, was significantly higher in Group CB than in Group CS, which may explain the reduction in compliance. Electron microscopy showed normal ultrastructure in Group CS but extracellular edema in Group CB. Total coronary blood flow showed a sustained increase during reperfusion in both groups. Oxygen consumption rose with rewarming to base-line levels in both groups, whereas lactate and pyruvate consumption was reduced in both groups, particularly Group CB. Cardioplegic solution thus appears to be superior to the intermittent perfusion of cold blood for myocardial protection. The addition of potassium arrest, by markedly reducing myocardial metabolism, improves the protection afforded by cold blood perfusion alone.     

Influence of normothermic systemic perfusion temperature on cold myocardial protection during coronary artery bypass surgery.

OBJECTIVE: To determine the effect of normothermic systemic perfusion on myocardial injury when using cold cardioplegic techniques in patients undergoing coronary artery bypass surgery. METHOD: Sixty six patients with stable angina pectoris were prospectively randomized into three groups according to cardiopulmonary bypass temperature: hypothermia (28 degrees C, n = 22), moderate hypothermia (32 degrees C, n = 22) and normothermia (37 degrees C, n = 22). All patients received cold antegrade crystalloid cardioplegia and topical cooling with saline at 4 degrees C. Serum samples were collected for troponin T and I estimation preoperatively, 4 hours after removal of the aortic cross clamp, and 12, 24, 36 and 48 hours postoperatively. In addition, serial electrocardiographic studies were undertaken on days 1, 3 and 5. RESULTS: Patients were similar with regard to preoperative and intraoperative characteristics Four patients showed ECG changes typical of perioperative myocardial infarction but remained clinically well (28 degrees C, one; 32 degrees C, one; 37 degrees C, two). In the remaining 62 patients, serum troponin T increased significantly from a mean baseline value of 0.02 ng/ml to 1.5+/-0.9 ng/ml 4 hours after removal of the aortic cross-clamp (P<0.0001). Similarly, troponin I increased from 0.06 ng/ml to 0.63+/-0.47 ng/ml 12 hours after reperfusion (P<0.0001). Serum concentrations of both markers subsequently declined with time but remained higher than preoperative values at 48 hours. There were no differences between the three groups with respect to peak and cumulative serum troponin release. Normothermic cardiopulmonary bypass did not compromise the efficacy of cold myocardial protection when assessed by serum troponin concentrations in low risk patients undergoing coronary revascularization.     

原位肾低温灌注腹腔镜下肾部分切除术

目的 探讨一种改进的原位肾低温灌注方法在腹腔镜下肾部分切除术中的临床价值.方法 2009年3-5月,对5例解剖性或功能性孤立肾患者行原位肾低温灌注腹腔镜下肾部分切除术.男3例,女2例;平均年龄49(39～63)岁;肿瘤位于左侧2例,右侧3侧;肿瘤直径平均5.6(3.8～7.0)cm.慢性肾功能不全2例,孤立肾1例,对侧肾萎缩1例,较大良性肿瘤1例.术前经皮穿刺经股动脉介入方法在患侧肾动脉留置带球囊契压导管1根,术中契压导管的球囊注水以阻断患侧肾动脉,并通过契压导管在加压泵下持续向肾动脉内灌注4℃冰盐水约200 ml,以实现患侧肾脏低温原位灌注,同时行腹腔镜下肾部分切除术,术后抽出球囊水以解除肾动脉阻断.结果 5例均成功施行原位肾低温灌注腹腔镜下肾部分切除术,手术时间平均102(80～120)min,肾动脉阻断时间平均35(29～39)min,术中出血量平均190(50～300)ml.低温灌注后皮肤温度平均降低0.6℃,肾脏表面温度降低10.0℃,肿瘤表面温度平均降低9.8℃.术前、术后第1、3、5和10天患者肌酐清除率分别为(64.7±16.9),(48.9±14.5)、(52.1±12.4)、(54.5±13.8)和(54.6±11.7)ml/min,多个相关样本检验显示,各组之间肌酐清除率比较差异有统计学意义(P=0.001).术后第5天和第10天比较差异无统计学意义(P=0.125),其余组间比较差异有统计学意义(P=0.043),术后第5天肌酐清除率基本稳定.结论 原位肾低温灌注腹腔镜下肾部分切除术安全可行,同时解决了腹腔镜下动脉阻断和低温灌注难题,有利于延长肾缺血时间、保护肾功能.     

Neurocognitive functions after aortic arch repair with right brachial artery perfusion

Background

Satisfactory neurologic outcome following aortic arch repair through right brachial artery perfusion is well established. However, how neurocognitive functions are affected following selective cerebral perfusion, still needs to be elucidated.

Methods

In a period between April 2002 and March 2003, 22 patients (19 male, 3 female, with a mean age of 46.8 ± 12; range: 26 to 70 years old), underwent aortic arch repair using right brachial artery low flow (8 to 10 mL · kg⁻¹ · min⁻¹) selective antegrade cerebral perfusion under moderate hypothermia (26°C). There were 6 Stanford type-A dissections and 16 ascending aortic aneurysms. All patients were evaluated preoperatively and postoperatively (at seventh day and second month) for neurocognitive functions.

Results

There was no operative mortality. The average cardiopulmonary bypass time was 115.0 ± 24.2 minutes and the average antegrade cerebral perfusion time was 29.8 ± 7.1 minutes (19 to 38 minutes). No major neurologic deficit was observed in the postoperative period. In terms of neurocognitive test results, between the preoperative and postoperative assessments for both hemispheric cognitive functions no deterioration was detected.

Conclusions

The low-flow selective antegrade cerebral perfusion technique through the right brachial artery may safely be used for the great majority of patients undergoing aortic arch repair without causing deteriorations in neurocognitive functions.     

Extracorporeal renal artery repair and autotransplantation

Seven renal artery lesions in 6 patients have been corrected by extracorporeal repair of the renal artery followed by autotransplantation. Short-term renal presevation was accomplished using readily available perfusion solutions. Six of the seven procedures were technically successful. One of the six technically successful procedures was a functional failure, with the patient ultimately receiving a cadaver kidney transplant. Five of the 6 patients are well and free symptoms, and 1 patient has recurrent disease in branches of the autotransplanted kidney and is again hypertensive.     

Embolic protection for renal artery stenting

A renal artery stenosis (RAS) is frequent and usually caused by atherosclerosis. Percutaneous renal artery angioplasty (PTRA) and stenting gives good immediate and long-term RESULTS: Concern has arisen in the postprocedural deterioration of the renal function (RF), which may occur in 20-40% of the patients therefore limiting the immediate benefits of the technique. Atheroembolism seems to play an important role in postprocedural deterioration. The authors postulated that the use of renal embolic protection devices could reduce the risk of renal embolism and avoid deterioration of the RF. One hundred forty-eight PTRA and stenting procedures were performed under protection in 121 hypertensive patients (M: 85), mean age: 64.5+/-11.8 years (22-87) with atherosclerotic renal artery stenosis. Eleven patients had solitary kidneys and 48 had renal insufficiency. Both occlusion balloons (N=46) and filters (N=95) were used. Of the 95 filters, the new FiberNet EP system (Lumen Biomedical) was included. This filter has the ability to capture particles as small as 30-40 microns without compromising flow. Generated debris was then removed and analysed, and blood pressure and serum creatinine levels were followed. Immediate technical success: was achieved in 100% os the cases. 112/141 lesions were stented directly. Visible debris with Percusurge (Medtronic) was aspirated and removed under aspiration from all patients and in 80% of the cases with filters. Debris was aspirated in 100% of the cases completed with the FiberNet). The mean particulate retrieved with the Percusurge system was 98.1+/-60.0 mu with a mean diameter ranging from 201+/-76 m (38-6 206). Mean occlusion time was 6.55+/-2.46 min and mean time in situ (filters) 4.2+/-1.1 min. Five times more particulate was removed with the FiberNet than with current available filters. One acute RF deterioration was observed. The mean follow-up was 29.6+/-14 months and the mean creatinine level remained constant during follow-up. At 6 months (101 patients) one deterioration of the RF in a patient with renal insufficiency at baseline was observed, 25 improvements in patients with renal insufficiency were noted, and 73 stabilizations. In conclusion 99% of the patients were stabilized or improved. After 2 years (84 patients) 95% of the patients remained stabilized (N=60) or showed improvements (N=20), and 4 patients had deterioration of RF (5%). The preliminary results suggest the feasibility and safety of distal protection during renal interventions to protect against atheroembolism and consequential deterioration of RF after the procedure. The beneficial effects of this technique should be evaluated further in randomized studies.     

Simultaneous bilateral renal artery reconstruction and intraoperative renal protection

A 22-year-old Japanese man with bilateral renal artery stenosis associated with hypertension underwent successfull surgery of simultaneous bilateral renal artery reconstruction under conditions of intraoperative renal perfusion with St. Thomas Hospital solution which is used for cardioplegia in open heart surgery. Circulation in the left kidney was interrupted for 58 minutes and that of the right kidney for 35 minutes. The patient fully recovered with no serious impairment of renal function. In addition to these stenotic lesions of the renal artery, there were medial necrosis of the aorta and fibromuscular dysplasia of the superior mesenteric artery. Administration of SQ14,225, an angiotensin I converting enzyme inhibitor, was effective in controlling hypertension during the preoperative period.     

Surgical repair of transplant renal artery stenosis with preserved cadaveric iliac artery grafts

OBJECTIVE: To review the authors' experience with ABO-matched, preserved, cadaveric, iliac artery grafts for treatment of transplant renal artery stenosis (TRAS). SUMMARY BACKGROUND DATA: TRAS is an important and treatable cause of hypertension and graft dysfunction in renal allograft recipients. Surgical treatment is reserved for lesions that are not amenable to percutaneous transluminal angioplasty (PTA) or for recurrence after PTA. Various surgical options for reconstruction of the transplant renal artery exist, although no single technique has been demonstrated to be superior. The authors have used preserved, blood type-matched, iliac artery grafts procured from cadaver organ donors to reconstruct transplant renal arteries in patients with specific lesions and following unsuccessful PTAs. METHODS: Between 1991 and 2001, 21 patients underwent reconstruction of allograft renal arteries using cadaveric iliac artery as conduit. Charts, operative notes, and imaging studies of all patients were reviewed. A successful intervention for TRAS was defined as technical success as well as a decrease in serum creatinine and/or blood pressure 6 weeks after the procedure. Development of a hemodynamically significant lesion following renal artery reconstruction was considered a recurrence. RESULTS: In patients treated with surgical reconstruction, hemodynamically significant TRAS occurred at or within 1 to 2 mm of the anastomosis in 13 patients, in the middle of the renal artery in 4, and secondary to a kink in 2 patients. Surgical treatment was undertaken in seven patients following unsuccessful PTA. Two patients had aneurysms of the iliac artery. Reconstruction using cadaveric iliac artery was successful in 19 of 21 (90%) patients, and only 1 these patients (4.8%) failed due to recurrence, with a median follow-up of 42 months. Graft loss secondary to TRAS occurred in two patients. The authors have not seen any long-term complications related to cadaveric iliac artery grafts, and the majority of the allografts continue to function well. CONCLUSIONS: Surgical reconstruction of the transplant renal artery with blood type-matched iliac artery grafts should be considered a viable option for patients with specific anatomic lesions, those who have had an unsuccessful PTA, and those with recurrence following PTA.     

Extended cadaver renal preservation with combined simple cold storage and hypothermic pulsatile perfusion

Although simple cold storage and hypothermic pulsatile perfusion are each accepted methods of cadaver kidney preservation the efficacy of combining these techniques for extended renal preservation is unclear. In 18 patients cadaver allografts were used that had been preserved with combined simple cold storage (range 6 to 20 hours) and hypothermic pulsatile perfusion (range 9 to 38 hours). The total interval of preservation for these kidneys ranged from 25 to 48 hours. Excellent post-transplant graft function was achieved in all cases, with a mean serum creatinine nadir of 1.4 mg./dl. In 14 patients (78 per cent) grafts continued to function at intervals of 3 to 38 months after transplantation. Of the remaining 4 patients 3 lost the grafts to rejection, while 1 died 7 months after transplantation with a well functioning graft. These data suggest that the combination of simple cold storage and hypothermic pulsatile perfusion provides a safe and effective method for extended renal preservation.     

Extracorporeal repair of renal artery branch lesions

Complex renal artery lesions which formerly would have been treated by nephrectomy may now be reconstructed by extracorporeal surgery and autotransplantation. Our experience in 15 patients (17 operations) with renal artery lesions extending into its branches or confined to them is described. Two patients underwent separate operations on both sides. The indications for surgery were severe renovascular hypertension (10 cases), renal artery aneurysm, (5 cases) and deteriorating renal function (2 cases). Overall clinical results after a mean follow up of 3 years were considered excellent in 13 procedures (11 patients). Improvement in 2 patients and failure in the other 2, who ultimately underwent nephrectomy. Discussion is focussed on results, vascular indications, (namely aneurysm, stenosis, dissecting aneurysm and trauma) and surgical techniques. Preservation of functioning renal tissue should be the ultimate goal of renovascular surgery where the ex vivo technique, when indicated, will achieve favorable results in most patients.     

Inadequate myocardial protection with cold cardioplegic arrest during repair of tetralogy of Fallot

Postoperative low cardiac output is the most common cause of death in patients undergoing elective repair of tetralogy of Fallot. The incidence is much higher than in elective adult bypass operations for coronary artery disease. To explain this difference, we investigated 16 children having elective repair of tetralogy (mean age 6.3 years). Myocardial biopsy specimens obtained during bypass before arrest, at the end of cold arrest by blood cardioplegia, and after 30 minutes of reperfusion were studied for adenosine triphosphate and lactate levels. Myocardium was submitted for microscopic study shortly after the onset of ischemia. The operation was successful in reducing right ventricular-pulmonary artery gradients from 82 +/- 28 to 9 +/- 1 mm Hg, yet seven patients required significant inotropic support (dopamine, greater than 5 micrograms/kg/min) for more than 24 hours and 12 patients needed prolonged use of digoxin and diuretics for right ventricular failure. Tissue levels of adenosine triphosphate and lactate in the tetralogy groups were compared with those in 20 adults with coronary artery disease having similar myocardial protection techniques. Adenosine triphosphate levels in the tetralogy group decreased during cross-clamping (41 +/- 8 minutes) from 24 +/- 3 to 16 +/- 2 mmol/kg dry weight (mean +/- 1 standard error), with a marked further drop after reperfusion to 9 +/- 2 mmol/kg (p less than 0.01). Adenosine triphosphate levels in the group with coronary disease also decreased from 20 +/- 1 to 16 +/- 1 mmol/kg after a longer cross-clamp time (70 +/- 17 minutes) but remained at 15 +/- 2 mmol/kg after reperfusion. Tissue lactate levels in the tetralogy group rose markedly during ischemia and remained elevated after reperfusion. In contrast, lactate levels in the group with coronary disease rose moderately during ischemia and returned to normal early on reperfusion. Microscopic study revealed focal myocyte necrosis in tetralogy of Fallot. Our findings, which demonstrate inadequate myocardial protection of patients with tetralogy during repair, with depression of adenosine triphosphate and increased lactate during ischemia and reperfusion, suggest a defect in oxidative metabolism. The drop in adenosine triphosphate after reperfusion in the patients with tetralogy implicates reperfusion injury as a mechanism of myocardial damage.     

Normothermic renal artery perfusion: A comparison of perfusates

Hypothermia and preservative perfusates have been used to decrease ischemic renal injury. This study was performed to identify the preservative function of perfusates independent of the effects of hypothermia. Rats underwent 45 minutes of renal ischemia. Rectal and renal parenchyma temperatures were monitored and maintained within 1° C of normal. Perfusates were University of Wisconsin solution (UW), Euro-Collins solution, normal saline solution, and Ringer's lactate solution. A nonperfused ischemic control and a nonischemic control group were also evaluated. Parameters evaluated included serum creatinine and blood urea nitrogen levels, renal ischemic injury grade, renal weight, and gross appearance of the injured kidney. Rats treated with UW solution were found to have a significantly lower creatinine, blood urea nitrogen, and injury grade than the other three perfused groups. The external gross appearance of the UW-treated kidneys was normal, whereas that of the other groups demonstrated moderate to severe injury. Although the mean right/left renal weight difference of the UW-treated group was lower than that of the other three groups, this was not statistically significant. Under normothermic conditions in rats, UW solution affords significant renal protection from ischemia. Euro-Collins, normal saline, and Ringer's lactate solutions display no significant protective effect.Presented at the Twentieth Annual Meeting of the Peripheral Vascular Surgery Society, New Orleans, La., June 10, 1995.