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Preclotting Grafts
CORRESPONDENCE
Preclotting Vascular Grafts To the Editor:
Preclotting Grafts To the Editor:
Fully cognizant of the occasional problems with bleeding that occur subsequent to insertion of prosthetic graft material while performing procedures requiring cardiopulmonary bypass, I could not help but be initially intrigued by the paper “A Technique for Preclotting Vascular Grafts” by Dr. M. F. X. Glynn and Dr. W. G. Williams (Ann Thorac Surg 29:182, 1980). However, a quick review of certain potential difficulties with this technique they describe proves rather discouraging. In Charleston, South Carolina, cryoprecipitate is provided to the patient through the American Red Cross. The final cost to the patient for each unit of cryoprecipitate is $93.00. Thus, the cost to the patient for the recommended 16 units of cryoprecipitate would be $1,488.00. The risk of hepatitis with an infusion of 1 unit of cryoprecipitate is the same as an infusion of 1unit of blood. Estimates of the risk of acquiring hepatitis from transfusion of 1 unit of blood depend on the marker chosen as a positive indicator of hepatitis. The incidence of overt posttransfusion hepatitis has been reported to be 0.0135% [l]. However, if sensitive laboratory procedures are used, the incidence of anicteric hepatitis has been found to be as high as 8.7% per unit transfused 121. Thus, the risk of hepatitis from the technique described requiring 16 units of cryoprecipitate may well range from 0.216% for icteric hepatitis to 100% for anicteric hepatitis. I certainly agree that a continual search for satisfactory techniques to prevent bleeding through graft material at the time of cardiopulmonary bypass must go on. However, the inordinate cost and risk of hepatitis in the technique proposed by Drs. Glynn and Williams would appear to make this approach unsatisfactory.
I am writing with reference to the article “A Technique for Preclotting Vascular Grafts” by Drs. Glynn and Williams (Ann Thorac Surg 29:182, 1980). Their technique is a resourceful way to preclot a graft in a patient who is already heparinized. However, the cost to the patient will run well over $200.00 for this technique, and I therefore suggest the use of several simple, alternate, known techniques. One is to thoroughly soak the graft in heparinized blood and autoclave it, following which it can be used. This makes the graft look terrible, but it works. A more logical method is to estimate by sonography or arteriography the patient’s aortic size, or merely estimate in advance the size of the graft needed (which will always be accurate enough except in the most unusual circumstances). Then do one of the following: draw blood from the patient before anesthesia is administered and preclot an appropriatesized graft accordingly; or use fresh blood from another patient donor, a doctor, or another patient under anesthesia, preclot the graft with this blood, and wash the graft liberally with normal saline solution. Three preclottings and washings are recommended. Donald L . Weeks, Jr., M . D 1235 S Orange A u e PO Box 8903 Orlando, FL 32856
Reply To the Editor:
The objections set out by Drs. Weeks and Kratz are serious and will be answered. First, the cost of a single bag of cryoprecipitate obtained from the Canadian Red Cross is between $5 and $10, Canadian. Second, in Canada the incidence of hepatitis John M . Kratz, M . D . after an infusion of blood products is not known with certainty. The incidence calculation is based on reDivision of Cardiothoracic Surgery porting by physicians, and any figure would cerMedical University of South Carolina tainly be an underestimate. Nevertheless, the avail171 Ashley A u e able figures are orders of magnitude less than those Charleston, SC 29403 quoted by Drs. Weeks and Kratz. The conclusion of 100% risk of anicteric hepatitis suggested by Dr. References Kratz should be regarded as just that-a suggestion 1. Polesky HF: Hepatitis associated with the transfu- rather than a conclusion. At one Canadian Red Cross sion of HB ag-negative blood. In Vyas GN, Perkins Centre, the incidence of icteric hepatitis is 8 cases per HA, Schmid R (eds): Hepatitis and Blood Transfu- 300,000 units of blood. A point that might have some sion. New York, Grune & Stratton, 1972, pp 363- bearing on the differences in the incidence of 364 hepatitis is that in Canada donors are unpaid. 2. Hampers CL, Prager D, Senior JR: Post-transThe costs and risks, however exaggerated, are fusion anicteric hepatitis. N Engl J Med 271:747, nonetheless formidable, and in order to overcome 1964 these impediments, at least in part, we have modified
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Preclotting Vascular Grafts To the Editor:
Preclotting Grafts To the Editor:
Fully cognizant of the occasional problems with bleeding that occur subsequent to insertion of prosthetic graft material while performing procedures requiring cardiopulmonary bypass, I could not help but be initially intrigued by the paper “A Technique for Preclotting Vascular Grafts” by Dr. M. F. X. Glynn and Dr. W. G. Williams (Ann Thorac Surg 29:182, 1980). However, a quick review of certain potential difficulties with this technique they describe proves rather discouraging. In Charleston, South Carolina, cryoprecipitate is provided to the patient through the American Red Cross. The final cost to the patient for each unit of cryoprecipitate is $93.00. Thus, the cost to the patient for the recommended 16 units of cryoprecipitate would be $1,488.00. The risk of hepatitis with an infusion of 1 unit of cryoprecipitate is the same as an infusion of 1unit of blood. Estimates of the risk of acquiring hepatitis from transfusion of 1 unit of blood depend on the marker chosen as a positive indicator of hepatitis. The incidence of overt posttransfusion hepatitis has been reported to be 0.0135% [l]. However, if sensitive laboratory procedures are used, the incidence of anicteric hepatitis has been found to be as high as 8.7% per unit transfused 121. Thus, the risk of hepatitis from the technique described requiring 16 units of cryoprecipitate may well range from 0.216% for icteric hepatitis to 100% for anicteric hepatitis. I certainly agree that a continual search for satisfactory techniques to prevent bleeding through graft material at the time of cardiopulmonary bypass must go on. However, the inordinate cost and risk of hepatitis in the technique proposed by Drs. Glynn and Williams would appear to make this approach unsatisfactory.
I am writing with reference to the article “A Technique for Preclotting Vascular Grafts” by Drs. Glynn and Williams (Ann Thorac Surg 29:182, 1980). Their technique is a resourceful way to preclot a graft in a patient who is already heparinized. However, the cost to the patient will run well over $200.00 for this technique, and I therefore suggest the use of several simple, alternate, known techniques. One is to thoroughly soak the graft in heparinized blood and autoclave it, following which it can be used. This makes the graft look terrible, but it works. A more logical method is to estimate by sonography or arteriography the patient’s aortic size, or merely estimate in advance the size of the graft needed (which will always be accurate enough except in the most unusual circumstances). Then do one of the following: draw blood from the patient before anesthesia is administered and preclot an appropriatesized graft accordingly; or use fresh blood from another patient donor, a doctor, or another patient under anesthesia, preclot the graft with this blood, and wash the graft liberally with normal saline solution. Three preclottings and washings are recommended. Donald L . Weeks, Jr., M . D 1235 S Orange A u e PO Box 8903 Orlando, FL 32856
Reply To the Editor:
The objections set out by Drs. Weeks and Kratz are serious and will be answered. First, the cost of a single bag of cryoprecipitate obtained from the Canadian Red Cross is between $5 and $10, Canadian. Second, in Canada the incidence of hepatitis John M . Kratz, M . D . after an infusion of blood products is not known with certainty. The incidence calculation is based on reDivision of Cardiothoracic Surgery porting by physicians, and any figure would cerMedical University of South Carolina tainly be an underestimate. Nevertheless, the avail171 Ashley A u e able figures are orders of magnitude less than those Charleston, SC 29403 quoted by Drs. Weeks and Kratz. The conclusion of 100% risk of anicteric hepatitis suggested by Dr. References Kratz should be regarded as just that-a suggestion 1. Polesky HF: Hepatitis associated with the transfu- rather than a conclusion. At one Canadian Red Cross sion of HB ag-negative blood. In Vyas GN, Perkins Centre, the incidence of icteric hepatitis is 8 cases per HA, Schmid R (eds): Hepatitis and Blood Transfu- 300,000 units of blood. A point that might have some sion. New York, Grune & Stratton, 1972, pp 363- bearing on the differences in the incidence of 364 hepatitis is that in Canada donors are unpaid. 2. Hampers CL, Prager D, Senior JR: Post-transThe costs and risks, however exaggerated, are fusion anicteric hepatitis. N Engl J Med 271:747, nonetheless formidable, and in order to overcome 1964 these impediments, at least in part, we have modified
97