Search

Blood obtained by intraoperative autotransfusion is: 1) readily available 2) sterile 3) compatible 4) normothermic 5) inexpensive and may be infused rapidly for volume support. We have made extensive modifications to commercially available equipment in order to provide a safe, effective IAT. The effects of IAT in our series of 85 patients are outlined below. Red Cell Mass is reduced after IAT because of irretrievable blood loss and hemolysis, and may be controlled by homologous transfusion when necessary. Red Cell Survival is normal after IAT. Hemolysis. Plasma free hemoglobin is consistently elevated after IAT, but clears within 24 hours. Platelets are normal for patients autotransfused less than 3,500 ml; micropore filters should not be used in cases where greater than 3,500 ml blood is expected to be reinfused; in cases where greater than 3,500 ml is reinfused, 10 units of platelets are recommended for every 3,000 ml of blood reinfused; IAT does effect platelets function; however, platelets circulating within the patient function normally. Coagulation. We use local ACD to eliminate extracorporeal surface clotting. Even with massive IAT we have never demonstrated any clinical or laboratory evidence of intravascular coagulopathy. "Dilutional coagulopathy" may be procuced when greater than 5,000 ml are reinfused, and may be controlled with fresh frozen plasma and platelet concentrates. Bilirubin levels were normal after IAT despite gross hemoglobinuria. Fat emboli were not noted after IAT. Air emboli must be a concern in IAT; HOWEVER, PROPER OPERATION AND EQUIPMENT MODIFICATION MAY ELIMINATE EMBOLI. Renal Failure was not noted after IAT. Alveolar-arterial Oxygen Difference and Blood Gases were normal after IAT. We feel IAT is not necessary if a blood loss less than 1,000 ml is expected. Also, if greater than 3,500 ml is expected additional backup (i.e. homologous transfusions, platelets, fresh frozen plasma) may be required. As banked donor blood reserves become more limited, IAT may become a routine part of general surgical procedures.

Femoral artery pressure (FAP) measurements were carried out to evaluate the hemodynamic significance of aorto-iliac occlusive disease in 150 patients (173 limbs) at the time of transfemoral angiography. Clinical assessment based upon traditional criteria of claudication level, pulse examination, and monoplane angiography were at variance with the results of this physiologic testing in approximately one-third of the patients. Results were most variable, and FAP testing most helful in evaluating patients with moderate diffuse disease on angiography, who are usually difficult to evaluate clinically. Strong correlation existed between FAP evaluation and the results of arterial reconstructive surgery. Of the patients with a positive FAP result who underwent proximal vascular reconstruction, 96% had satisfactory relief of ischemic symptoms despite uncorrected distal disease in the majority. In contrast, 57% of the patients undergoing proximal operation despite a normal FAP result were unrelieved of symptoms and required subsequent distal procedures. Similar correlation existed with results of femoro-popliteal and femoro-femoral grafting. This simple physiologic test has been found of great value in selecting the proper level of arterial reconstruction and in accurately predicting the results of surgery.

The utility of transcutaneous oxygen tension measurements in selection of a reliable amputation level was evaluated. Measurements were made at the proposed level of amputation in 37 patients, 22 of whom underwent major limb amputation and in 15 amputation was confined to the forefoot or toes. In patients with successful amputation healing, mean transcutaneous oxygen tension on the anterior skin surface was 50 +/- 8 mm Hg (index 0.79 +/- 0.1 mm Hg). In contrast, patients with failure of healing had a mean transcutaneous oxygen tension of 22 +/- 16 mm Hg (index 0.32 +/- 0.19 mm Hg) (p less than 0.001). Measurements on the posterior or plantar skin surface and posteroanterior differences provided even greater separation between success and failure groups, with no overlap of transcutaneous oxygen tension values or index. Transcutaneous oxygen tension measurement is easily obtained and noninvasive, and can be applied to all patients irrespective of Doppler signals, noncompressible vessels, or painful lesions. Transcutaneous oxygen tension appears to predict successful healing with accuracy, and should be a useful addition to clinical judgment in selection of optimal amputation level.

Of 15 patients having revascularization of the right renal artery with the use of the hepatic circulation from May 1984 through March 1987 at the Massachusetts General Hospital, eight patients had this accomplished with end-to-end anastomosis of the gastroduodenal artery and right renal artery. Operative indications were acute azotemic renal failure (three patients), poorly controlled renovascular hypertension (four patients), and staged repair of bilateral renal artery disease (one patient). All revascularizations were successful in restoring renal function or rendering hypertension manageable and were assessed by means of renal flow scans, celiac angiography, or return of function in those patients with a solitary, functioning kidney. All patients survived the operation with one late death caused by myocardial infarction after abdominal aortic aneurysm repair. The gastroduodenal artery may be used as the source for arterial inflow in revascularization of the right renal artery by end-to-end anastomosis in approximately 50% of instances, conferring the advantage of the use of only one anastomosis and obviating the long-term possibility of vein graft failure.