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Acid-base balance and renal function following total body perfusion
Volume 61 Number 2
istics that Dr. Zipursky has shown you. This would be an important value to know; that is why I mention it here. Our calculations indicate that the cell content of fetal hemoglobin must be 7 to 15 per cent of the total hemoglobin before it will show acid resistance. While I'm mentioning this (and this was derived from calculations very similar to the kind that Dr. Zipursky has shown), I might say something that he did not mention but that I'm sure he is very much aware of. There are gradations in the staining intensity which permit us to make a rough guess; that these cells are not all uniform. The second point, and again I am sure that Dr. Zipursky is aware of it, is that in the type of hematologic disorders that he has mentioned, there is variability, not only from patient to patient as he has shown, but also from time to time. For example, in some cases which we think are homozygous sickle cell anemia all the cells will contain some fetal hemoglobin as shown by staining reaction, while in other cases that otherwise seem to behave very similarly, only some of the cells will contain fetal hemoglobin but these will be rather densely stained. We interpret this, then, as evidence that environmental factors have to do with the rate of hemoglobin synthesis that is forced on the bone marrow or even Oll the individual erythrocyte precursor at the time when it discharges these particular cells in the circulation. A. ZIPURSKY, WINNIPEG. We have observed also gradations in staining intensity of the cells containing fetal hemoglobin. This is evident both in the blood smears of infants and in the patients described today. Although such observations are qualitative only, they suggest that the concentration of hemoglobin F may vary greatly from cell to cell. We have no information regarding time to time variation in our thalassemia patients. D. SMITH, MADISON. I wonder if you have any information regarding the fetal hemoglobin content of cells in the nonresponsive anemias, the congenital erythroid hypoplasias, the aplastic anemias, etc., particularly before and after erythropoietic activity associated with hormone administration. A. ZIPURSKY,WINNIPEG. We have studied one patient with congenital erythroid hypoplasia; this patient had elevated levels of hemoglobin F with a distribution of fetal hemoglobin similar to that of the patients described today. We have not studied any patients with aplastic anemia.
Abstracts Midwest Soc. Pediat. Res. 2 8 7
Acid-base balance a n d renal function following total body perfusion James G. Calene, William H. Weidman, Khalil G. Wakim, John W. Rosevear, John W. Kirklin, and Gunnar B. Stickler. F r o m the M a y o Clinic a n d M a y o F o u n d a tion, Rochester, M i n n . Acidemia is known to occur during" the postoperative period in patients who have had cardiac operation involving total body perfusion. Not alI the factors contributing to the disturbed acid-base balance are known. Therefore, we studied 12 patients who had a cardiac operation with extracorporeal circulation and 8 patients who had a major operation without total body perfusion to determine the acid-base disturbance and its possible relation to renal function in the preoperative and postoperative periods. All patients in the perfusion group were on the same fluid regimen. The glomerular filtration rate and renal plasma flow, the levels of titratable acidity and ammonium in the urine, and the values for the pI-I, pCO2, standard bicarbonate, actual bicarbonate, and buffer base of the venous blood were determined immediately before operation and 2 to 4 hours, 20 to 24 hours, and 40 to 44 hours after operation. The patients who had operations without extracorporeal circulation showed only minor changes in the pH of the blood 2 to 4 hours postoperatively and a slight increase in renal plasma flow and urinary excretion of hydrogen ion 20 to 24 hours after operation. A pronounced difference was noted in the group of patients who had extracorporeal circulation compared with the other group. Two hours postoperatively, a significant metabolic acidosis was present, with a fall in pH much greater than that seen in the general operative patients. This was accompanied by a definite fall in the level of standard bicarbonate in the venous blood and by a moderate increase in urinary excretion of hydrogen ion. The glomerutar filtration rate was unchanged, but there was a significant diminution of renal plasma flow. The glomerular filtration rate and renal plasma flow increased after 24 and 44 hours, respectively, with an increase in urinary excretion of hydrogen ion, a rise in the level of standard blcarbo-
Abstracts--Midwest Soc. Pedlar. Res,
August 1962
nate, and a return of the pH of-the Mood toward normal. The values for glomerular filtration rate, urinary excretion of hydrogen ion, and the rapidity with which the pH of the blood returned toward normal showed some correlation. The pCO 2 of mixed venous blood was normal immediately after operation, but it became elevated in the ensuing 40 hours, indicating an associated respiratory acidosis. In conclusion, patients who had total body perfusion differed from patients with thoracic or abdominal operations without extracorporeal circulation in that they exhibited more severe acidemia. Metabolic acidosis was present, although at decreasing levels, throughout the postoperative period. In some patients acidemia was aggravated after 2 to 4 hours postoperatively by the retention of carbon dioxide. The severity of the metabolic acidosis appeared to be related, at least, in part, to an inadequate increase in urinary excretion of hydrogen ion.
you speculate on whether a higher flow rate (about 3 L. per minute per square meter) would obviate the findings that you have presented. W. WEIDMAN, ROCHESTER. Dr. Kaplan, we could not relate severity of acidosis to the duration of extracorporeal circulation. Nor was there any noticeable difference between those patients under hypothermia and those operated on under normothermic conditions. Of course, there is a possibility that the acidosis could be more severe in the first two postoperative hours, but we have no measurements in that peroid. I don't know whether flow rates higher than we used would have an effect on the metabolic acidosis. M. HOLLIDAY, PITTSBURGH. Dr. William Schwartz showed that the nature of the anion associated with the acid load was a very important determinant in the rate of hydrogen ion secretion by the kidney. I wondered if this couldn't be a factor in the difference you imply between your patients and the ones that Elkington loaded with ammonium chloride which is a fairly rapidly excreted anion. Ammonium chloride increases the rate of hydrogen ion excretion. W. WEIDMAN,ROCHESTER. I 'm sure this may be true, but we did not determine the anion.
288
DISCUSSION A. HARTMANN,JR., ST. LouIs. Do you have any information with regard to cardiac output at the time the renal plasma flow was low? Do you have any correlation between the type of case or the amount of operation that was performed with regard to the amount of acidosis which was present postoperatively? W. WEIDMAN,ROCHESTER. In answer to the first question, we did not measure cardiac output. In answer to the second question, there was no correlation between type of operation and severity of acidosis. S. KAPLAN, CINCINNATI. I wondered if you could relate the severity of metabolic acidosis to the duration of perfusion; that is, the longer the perfusion the more severe the acidosis. Also, have you studied the acid-base balance of patients in whom hypothermia was induced during the perfusion? In our experience, the severity of acidosis can increase during the first two hours after total body perfusion or in some instances recovery toward normal may occur in this two hour period. In other words, it is possibIe that the pH may have been more acid than suggested by the data obtained 2 hours after cardiopulmonary bypass. We have used tris buffer during the perfusion of 12 patients when the continuous arterial pH record indicated a trend toward the development of acidosis. It is our impression that this buffer has modified the severity of acidosis. Last, would
S. FOMAN, IOWA CITY. Because of the presumably significant difference in renal plasma flow of the two groups before operation, it would seem difficult to interpret the change in renal plasma flow after perfusion. W. WEIDMAN, ROCI-IESTER. The low mean preoperative renal plasma flow in the control group was the result of the inclusion of one severely ill patient who had a very low renal plasma flow. If this patient were excluded, the mean value would approach that of the perfusion group.
External calcium and phosphorus balances in vitamin D--resistanl rickets Gunnar B. Stickler, M.D. From the Mayo Clinic, Rochester, Mi n n . Albright, in his first publication on vitamin D-resistant rickets, in 1937, described the defect in absorption of calcium from the gastrointestinal tract that could be reversed by the administration of very large doses of vitamin D. Subse-
istics that Dr. Zipursky has shown you. This would be an important value to know; that is why I mention it here. Our calculations indicate that the cell content of fetal hemoglobin must be 7 to 15 per cent of the total hemoglobin before it will show acid resistance. While I'm mentioning this (and this was derived from calculations very similar to the kind that Dr. Zipursky has shown), I might say something that he did not mention but that I'm sure he is very much aware of. There are gradations in the staining intensity which permit us to make a rough guess; that these cells are not all uniform. The second point, and again I am sure that Dr. Zipursky is aware of it, is that in the type of hematologic disorders that he has mentioned, there is variability, not only from patient to patient as he has shown, but also from time to time. For example, in some cases which we think are homozygous sickle cell anemia all the cells will contain some fetal hemoglobin as shown by staining reaction, while in other cases that otherwise seem to behave very similarly, only some of the cells will contain fetal hemoglobin but these will be rather densely stained. We interpret this, then, as evidence that environmental factors have to do with the rate of hemoglobin synthesis that is forced on the bone marrow or even Oll the individual erythrocyte precursor at the time when it discharges these particular cells in the circulation. A. ZIPURSKY, WINNIPEG. We have observed also gradations in staining intensity of the cells containing fetal hemoglobin. This is evident both in the blood smears of infants and in the patients described today. Although such observations are qualitative only, they suggest that the concentration of hemoglobin F may vary greatly from cell to cell. We have no information regarding time to time variation in our thalassemia patients. D. SMITH, MADISON. I wonder if you have any information regarding the fetal hemoglobin content of cells in the nonresponsive anemias, the congenital erythroid hypoplasias, the aplastic anemias, etc., particularly before and after erythropoietic activity associated with hormone administration. A. ZIPURSKY,WINNIPEG. We have studied one patient with congenital erythroid hypoplasia; this patient had elevated levels of hemoglobin F with a distribution of fetal hemoglobin similar to that of the patients described today. We have not studied any patients with aplastic anemia.
Abstracts Midwest Soc. Pediat. Res. 2 8 7
Acid-base balance a n d renal function following total body perfusion James G. Calene, William H. Weidman, Khalil G. Wakim, John W. Rosevear, John W. Kirklin, and Gunnar B. Stickler. F r o m the M a y o Clinic a n d M a y o F o u n d a tion, Rochester, M i n n . Acidemia is known to occur during" the postoperative period in patients who have had cardiac operation involving total body perfusion. Not alI the factors contributing to the disturbed acid-base balance are known. Therefore, we studied 12 patients who had a cardiac operation with extracorporeal circulation and 8 patients who had a major operation without total body perfusion to determine the acid-base disturbance and its possible relation to renal function in the preoperative and postoperative periods. All patients in the perfusion group were on the same fluid regimen. The glomerular filtration rate and renal plasma flow, the levels of titratable acidity and ammonium in the urine, and the values for the pI-I, pCO2, standard bicarbonate, actual bicarbonate, and buffer base of the venous blood were determined immediately before operation and 2 to 4 hours, 20 to 24 hours, and 40 to 44 hours after operation. The patients who had operations without extracorporeal circulation showed only minor changes in the pH of the blood 2 to 4 hours postoperatively and a slight increase in renal plasma flow and urinary excretion of hydrogen ion 20 to 24 hours after operation. A pronounced difference was noted in the group of patients who had extracorporeal circulation compared with the other group. Two hours postoperatively, a significant metabolic acidosis was present, with a fall in pH much greater than that seen in the general operative patients. This was accompanied by a definite fall in the level of standard bicarbonate in the venous blood and by a moderate increase in urinary excretion of hydrogen ion. The glomerutar filtration rate was unchanged, but there was a significant diminution of renal plasma flow. The glomerular filtration rate and renal plasma flow increased after 24 and 44 hours, respectively, with an increase in urinary excretion of hydrogen ion, a rise in the level of standard blcarbo-
Abstracts--Midwest Soc. Pedlar. Res,
August 1962
nate, and a return of the pH of-the Mood toward normal. The values for glomerular filtration rate, urinary excretion of hydrogen ion, and the rapidity with which the pH of the blood returned toward normal showed some correlation. The pCO 2 of mixed venous blood was normal immediately after operation, but it became elevated in the ensuing 40 hours, indicating an associated respiratory acidosis. In conclusion, patients who had total body perfusion differed from patients with thoracic or abdominal operations without extracorporeal circulation in that they exhibited more severe acidemia. Metabolic acidosis was present, although at decreasing levels, throughout the postoperative period. In some patients acidemia was aggravated after 2 to 4 hours postoperatively by the retention of carbon dioxide. The severity of the metabolic acidosis appeared to be related, at least, in part, to an inadequate increase in urinary excretion of hydrogen ion.
you speculate on whether a higher flow rate (about 3 L. per minute per square meter) would obviate the findings that you have presented. W. WEIDMAN, ROCHESTER. Dr. Kaplan, we could not relate severity of acidosis to the duration of extracorporeal circulation. Nor was there any noticeable difference between those patients under hypothermia and those operated on under normothermic conditions. Of course, there is a possibility that the acidosis could be more severe in the first two postoperative hours, but we have no measurements in that peroid. I don't know whether flow rates higher than we used would have an effect on the metabolic acidosis. M. HOLLIDAY, PITTSBURGH. Dr. William Schwartz showed that the nature of the anion associated with the acid load was a very important determinant in the rate of hydrogen ion secretion by the kidney. I wondered if this couldn't be a factor in the difference you imply between your patients and the ones that Elkington loaded with ammonium chloride which is a fairly rapidly excreted anion. Ammonium chloride increases the rate of hydrogen ion excretion. W. WEIDMAN,ROCHESTER. I 'm sure this may be true, but we did not determine the anion.
288
DISCUSSION A. HARTMANN,JR., ST. LouIs. Do you have any information with regard to cardiac output at the time the renal plasma flow was low? Do you have any correlation between the type of case or the amount of operation that was performed with regard to the amount of acidosis which was present postoperatively? W. WEIDMAN,ROCHESTER. In answer to the first question, we did not measure cardiac output. In answer to the second question, there was no correlation between type of operation and severity of acidosis. S. KAPLAN, CINCINNATI. I wondered if you could relate the severity of metabolic acidosis to the duration of perfusion; that is, the longer the perfusion the more severe the acidosis. Also, have you studied the acid-base balance of patients in whom hypothermia was induced during the perfusion? In our experience, the severity of acidosis can increase during the first two hours after total body perfusion or in some instances recovery toward normal may occur in this two hour period. In other words, it is possibIe that the pH may have been more acid than suggested by the data obtained 2 hours after cardiopulmonary bypass. We have used tris buffer during the perfusion of 12 patients when the continuous arterial pH record indicated a trend toward the development of acidosis. It is our impression that this buffer has modified the severity of acidosis. Last, would
S. FOMAN, IOWA CITY. Because of the presumably significant difference in renal plasma flow of the two groups before operation, it would seem difficult to interpret the change in renal plasma flow after perfusion. W. WEIDMAN, ROCI-IESTER. The low mean preoperative renal plasma flow in the control group was the result of the inclusion of one severely ill patient who had a very low renal plasma flow. If this patient were excluded, the mean value would approach that of the perfusion group.
External calcium and phosphorus balances in vitamin D--resistanl rickets Gunnar B. Stickler, M.D. From the Mayo Clinic, Rochester, Mi n n . Albright, in his first publication on vitamin D-resistant rickets, in 1937, described the defect in absorption of calcium from the gastrointestinal tract that could be reversed by the administration of very large doses of vitamin D. Subse-