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Additional information on the Doppler blood pressure measurement technique
May, 1972 T h e Journal o[ P E D I A T R I C S 891
Letters to the Editor
Additional information on the Doppler blood pressure measurement technique To the Editor: There are a few minor points which should be cleared in regard to our article on blood pressure measurement (J. PEDIATR. 79: 300, 1971). Distinct and clear wall motion signals as detected by Doppler ultrasound for blood pressure measurement are best produced just distal to the point of maximal cuff pressure. As the Doppler transducer is moved further distally from the midportion of the cflff, more flow signal and less wall motion signal is noted. This becomes particularly true in the neonate and the patient in shock. The instrument used in our study was developed for blood flow determination. Experimental instruments, and more recently, the Arteriosonde (Hoffman-La Roche) are filtered to eliminate most of the flow signal and emphasize the wall motion signals. Dr. Ray Ware, who devised this technique of blood pressure determination, predicted the above findings on theoretical grounds. His original papers describe these physical phenomena (Third Natl. Biomed. Sci. Instrument. Symp., ISA-BM, 65, and Proc. Symp. Objective Recording of Blood Pressure, p. 37. Sponsored by the American Heart Association, New York, United States Public Health Service, and Chicago Heart Association, Chicago, 1966).
William T. Kemmerer, Colonel, USAF (MC) Department of the Air Force Lackland Air Force Base, Texas
Antibody response in patients with leukemia To the Editor: It is the opinion of this writer that the findings of Ogra and associates 1 are most significant. As they have suggested, immunosuppression as a
result of chemotherapy may have contributed to impaired antibody responses. The possibility that other factors are operative in leukemic patients is entertained. I had occasion to study three patients who developed acute leukemia in this local area within a 1 month period three years ago. Although all three had respiratory infection dating back at least three weeks previously, the IgM globulin levels before immunosuppression were as follows: in a 6-year-old child, 56 nag. per cent; in a 2-year-old child, 69 mg. per cent; and in a 7-year-old child, 42 mg. per cent. Eighteen months later in one of these patients, who had been on a particularly low dose of an immunosuppressive drug, there appeared to be an inverse relationship in fluctuation between the serum IgM level and the absolute number of blasts in the peripheral blood. This has been alluded to in correspondence elsewhere, z The nature of the blast cell and its relationship to IgM globulin deserves much speculation. The fortuitous investigation of Fialkow and associates, ~ in Seattle, in which they have documented leukemic transformation of engrafted human marrow cells in vivo, sheds new light on this. That the blast is part of the total immune reaction in these patients does not seem unlikely. It is my impression that the leukemic process may represent the orderly disintegration of the immune system under excessive antigenic stress. With the disappearance of the humoral IgM globulin response, the more primitive cell-mediated response becomes operative with an outpouring of blast cells. The work of Jarrett 4 in leukemia in lower animals is worthy of note. He found that in newborn cats injected with leukemia virus, there is a subsequent "viral thymectomy" in the next 6 to 8 weeks with histologic changes in the thymic-dependent areas of the lymph nodes. He expresses the opinion that there is no doubt that immunosuppression is produced by feline leukemia virus. The role of virus in the etiology of human leukemia is still unclear. In my experience with
Vol. 80, No. 5, pp. 891-897
Letters to the Editor
Additional information on the Doppler blood pressure measurement technique To the Editor: There are a few minor points which should be cleared in regard to our article on blood pressure measurement (J. PEDIATR. 79: 300, 1971). Distinct and clear wall motion signals as detected by Doppler ultrasound for blood pressure measurement are best produced just distal to the point of maximal cuff pressure. As the Doppler transducer is moved further distally from the midportion of the cflff, more flow signal and less wall motion signal is noted. This becomes particularly true in the neonate and the patient in shock. The instrument used in our study was developed for blood flow determination. Experimental instruments, and more recently, the Arteriosonde (Hoffman-La Roche) are filtered to eliminate most of the flow signal and emphasize the wall motion signals. Dr. Ray Ware, who devised this technique of blood pressure determination, predicted the above findings on theoretical grounds. His original papers describe these physical phenomena (Third Natl. Biomed. Sci. Instrument. Symp., ISA-BM, 65, and Proc. Symp. Objective Recording of Blood Pressure, p. 37. Sponsored by the American Heart Association, New York, United States Public Health Service, and Chicago Heart Association, Chicago, 1966).
William T. Kemmerer, Colonel, USAF (MC) Department of the Air Force Lackland Air Force Base, Texas
Antibody response in patients with leukemia To the Editor: It is the opinion of this writer that the findings of Ogra and associates 1 are most significant. As they have suggested, immunosuppression as a
result of chemotherapy may have contributed to impaired antibody responses. The possibility that other factors are operative in leukemic patients is entertained. I had occasion to study three patients who developed acute leukemia in this local area within a 1 month period three years ago. Although all three had respiratory infection dating back at least three weeks previously, the IgM globulin levels before immunosuppression were as follows: in a 6-year-old child, 56 nag. per cent; in a 2-year-old child, 69 mg. per cent; and in a 7-year-old child, 42 mg. per cent. Eighteen months later in one of these patients, who had been on a particularly low dose of an immunosuppressive drug, there appeared to be an inverse relationship in fluctuation between the serum IgM level and the absolute number of blasts in the peripheral blood. This has been alluded to in correspondence elsewhere, z The nature of the blast cell and its relationship to IgM globulin deserves much speculation. The fortuitous investigation of Fialkow and associates, ~ in Seattle, in which they have documented leukemic transformation of engrafted human marrow cells in vivo, sheds new light on this. That the blast is part of the total immune reaction in these patients does not seem unlikely. It is my impression that the leukemic process may represent the orderly disintegration of the immune system under excessive antigenic stress. With the disappearance of the humoral IgM globulin response, the more primitive cell-mediated response becomes operative with an outpouring of blast cells. The work of Jarrett 4 in leukemia in lower animals is worthy of note. He found that in newborn cats injected with leukemia virus, there is a subsequent "viral thymectomy" in the next 6 to 8 weeks with histologic changes in the thymic-dependent areas of the lymph nodes. He expresses the opinion that there is no doubt that immunosuppression is produced by feline leukemia virus. The role of virus in the etiology of human leukemia is still unclear. In my experience with
Vol. 80, No. 5, pp. 891-897