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Use of dopamine for shock in neonates
852
Editorial correspondence
The Journal of Pediatrics May 1979
Table
3.
Subjects (No.)
No. of
No. of
4.
Proteus mirabilis (%)
E. Coli (%)
5. 6.
Circumcised (16)
I l (69)*
5 (3 l)i-
Not circumcised (25)
14 (56)*
11 (44)t
7. *P = 0.3. tP = 0.1. infection (UTI) in a group of boys of whom 85% had been circumcised. Investigators reporting a higher incidence 1-5 of P. mirabilis, comparable to our own, studied predominantly uncircumcised boys or failed to mention the presence or absence of foreskin. The need to relate the type of organism to circumcision on UTI is appropriate. Our data were not analyzed for the presence of foreskin, but now have been (Table). There was no difference in distribution of P. mirabilis or E. coli in the two groups. Hence, the presence of foreskin was not the determinant factor in selecting this organism in our series. The possible role of prepucial colonization by P. mirabilis and other organisms in the pathogenesis of UTI has been the subject of a few inconclusive studies?. ~ It is also not known if the foreskin affects urethral meatal flora as suggested by Dr. Cohen. Maskell et ale determined the prepucial and meatal flora of 49 boys with UTI and 51 controls. Only four circumcised subjects were included in this study, and apparently no organism(s)" was isolated from these four, or at least not mentioned. Our observations indicate the need to elucidate factor(s) other than foreskin for the variation in prevalence of P. mirabilis reported in California (Dr. Cohen) and other parts of the world. This seems important since the incidence among girls (3%), reported by Dr. Cohen previously, 7 is also much lower than found elsewhere. ~-4 It seems reasonable to speculate that" the relatively warm climate of California favors a lower incidence (2 to 3%) of P. mirabilis; the cold weather of northern areas on either side of the Atlantic seems conducive to higher incidence rates such as 23% in Norway, 3 32% Sweden) 38, 2 591 and 75%' in the United Kingdom, and 58% in New York.
Abdul J. Khan, M.D. Ramesh S. Ubriani, M.D. Edith Bombach, M.D. Melanie M. Agbayani, M.D. Harold Ratner, M.D. Hugh E. Evans, M.D. Department of Pediatrics Jewish Hospital and Medical Center of Brooklyn 555 Prospect Place Brooklyn, NY 11238 REFERENCES 1. Hallet RJ, Pead L, Muskell R: Urinary tract infection in boys, Lancet 2:1107, 1976. 2. Saxena SR, and Bassett DC: Sex related incidence in Proteus infection of urinary tract in childhood, Arch Dis Child 50:899, 1976.
Bahna SL, and Torp KH: The sex variable in childhood urinary tract infection, Acta Pediatr Scand 64:581, 1975. Mann PG: Proteus mirabilis urinary infections in childhood, J Clin Pathol 25:551, 1972. Bergstrom T: Sex differences in childhood urinary tract infections, Arch Dis Child 47:227, 1972. Maskell R, Pead L, and Hallett R J: Urinary tract pathogens in the male, Br J Urol 47:691, 1975. Cohen M: Urinary tract infection in children I. Females aged 2 through 14, first two infections, Pediatrics 50:271, 1972.
Use of dopaminefor shock in neonates To the Editor: The report by Driscoll et al' on the use ofdopamine in children seems to be carefully done; attention is given to the spectrum of responses to dopamine in various organ systems, at dose ranges from 2 to 20/~g. The authors point out that, in critically/ll infants suffering from cardiovascular collapse, the use of dopamine increases urine output, peripheral perfusion, and blood pressure. To be sure, careful attention must be paid to use of the appropriate rate of infusion. Kliegman and Fanarofl~ point out that, in a spontaneously breathing neonate, dopamine may depress peripheral chemoreceptor activity and minute volume. Even should this occur, respiratory depression would not represent a contraindication to the use of dopamine in an infant in shock; the infant could always be intubated if necessary. Kliegman and Fanaroff further state that dopamine may adversely affect pulmonary circulation by increasing pulmonary vascular resistance. No mention is made of the dopamine infusion rate at which pulmonary vasoconstriction would occur, but this effect would be observed at higher infusion rates, owing to the alpha adrenergic, norepinephrinelike property of dopamine. The beneficial effects on urine flow, gut perfusion, and blood pressure are generally observed at lower doses than those at which vasoconstriction is manifest. Kliegman and Fanaroff correctly point out that many sick neonates already have elevated pulmonary vascular resistance, resulting in persistence of the fetal circulation, and in these infants dopamine could worsen the situation. These infants should in any case be treated with Priscoline (tolazoline) given by central venous line to reduce pulmonary vasuclar resistance. Dopamine could be added to the regimen to increase urinary output, and gut and peripheral perfusion. Kliegman and Fanaroff propose the use of isoproterenol instead of dopamine, because of the presumed disadvantages of dopamine, and the ability of isoproterenol to decrease pulmonary vascular resistance. As noted, tolazoline would be an effective means to reduce the pulmonary vascular resistance. Furthermore, many animal studie# have shown that isoproterenol does not increase renal and mesenteric blood flow and in fact reduces both, by shunting of blood to skin and skeletal muscle. By the same mechanism, bypotension often results from the use of
Volume 94 Number 5
Editorial correspondence
iosproterenol, a situation clearly disastrous in the face of preexisting shock. In summary, Driscoll et al have presented data indicating the usefulness of dopamine in the treatment of shocky infants. The disadvantages pointed out by Kliegman and Fanaroff are real, but by no means contraindications to the use of dopamine. Dopamine, like all other pharmacologic agents, must be used with careful attention to dosage and possible side effects. Paul H. Volkman, M.D. Ph.D. Departments of Pediatrics and Pharmacology Loyola University Medical Center Maywood, IL 60153 REFERENCES
1. Driscoll DJ, Gillette PC, and McNamara DC: The use of dopamine in children, J PEDIATR 92:309, 1978. 2. Kliegman R, and Fanaroff AA: Caution in the use of dopamine in th e neonate, J PEDIATR 93:541, 1978 3. McNay JL, and Goldberg LI: Comparison of the effects of dopamine, isoproterenol, and norepinephrine, and bradykinin on canine renal and femoral blood flow, J Pharmacol Exp Ther 151:23, 1%6.
nepty To the Editor: As Dr. Volkman indicates, the cardiovascular response to dopamine is quite dose dependent; increased cardiac output and renal blood flow can occur at doses of the drug insufficient to cause systemic vasoconstriction. I share Dr. Kliegman's and FanaroWs L concern about using dopamine in sick neonates with cardiovascular shock and elevated pulmonary vascular resistance. Although there are unpul~lished anecdotal reports of the efficacy of tolazoline and dopamine for treatment of these infants, it would be important to document the usefulness of this therapy. David J. Driscoll, M.D. Pediatric Cardiology Texas Children's Hospital 6621 Fannin Houston, Texas 77030 REFERENCE 1. Kliegman R, and Fanaroff AA: Caution in the use of dopamine in the neonate, J PEDIATR 93:541, 1978.
Urinary catecholamines and metabolites in children To the Editor: This letter is in reference to the paper by De Schaepdryver et aP in the August issue Of THE JOURNAL. The authors state "Specimens containing tess than 1 gm creatinine/24 hours were assumed to reflect incomplete collections and were not included
853
in the study." This statement is based on studies carried out by Epstein et al.'-' Although it was not stated explicitly, it seems that these studies were performed in adults and not in children. Urinary creatinine excretion reflects muscle mass? Furthermore, calculation of normal plasma creatinine and glomerular filtration for the respective age group will demonstrate expected values of urinary creatinine well below those found by the authors. It is highly unlikely that the infants and children studied will, indeed, have urinary creatinine excretion of 1 gm and above. A more accurate determination of urinary creatinine may prove to be helpful in using urinary creatinine excretion as.a reference value in expressing urinary catecholamines excretion. Mordechay Aladjem, M.D. Pediatric Renal Unit The Chaim Sheba Medical Center, Tel-Hashomer, Israel Affiliated to the TeI-A viv University Sackler School of Medicine, Ramat-A viv REFERENCES
1. De Schaepdryver AF, Hooft C, Delbeke M J, and Van der Noortgaete M: Urinary catecholamines and metabolites in children, J I~DIATR 93:266, 1978. 2. Epstein SE, and Schriever HG: Creatinine excretion, Lancet 1:i92, 1970. 3. Black D, editor: Urinalysis and assessment of renal function, Chapter 9, in Renal disease, 3 ed, London, 1972 Blackwell Scientific Publications, p 261.
Reply To the Editor: Dr. Aladjem is perfectly right: the incriminated sentence: "Specimens... in the study," reflects our reasoning when handling 24-hour urine samples from adults and was in fact not adopted in this study: it simply is not possible to adopt this reasoning since almost all samples did not contain 1 gm creatinine/24 hours; there were a few exceptions.which contained more than 1 gm creatinine and which for this reason were not included in the study, since they in all probability reflected samples of a collection extending over more than 24 hours. Although this mistake does not invalidate the actual values reported in the paper, we apologize for this error. A. De Schaepdryver, M.D. Heymans Institute of Pharmacology University of Ghent Medical School De Pintelaan 135 B-9000 Ghent, Belgium
Differentiation of adrenal and renal carcinoma To the Editor: We read with interest the report of Andler et aP in the October, 1978, issue of THfi JOURNAL. We question the evidence presented
Editorial correspondence
The Journal of Pediatrics May 1979
Table
3.
Subjects (No.)
No. of
No. of
4.
Proteus mirabilis (%)
E. Coli (%)
5. 6.
Circumcised (16)
I l (69)*
5 (3 l)i-
Not circumcised (25)
14 (56)*
11 (44)t
7. *P = 0.3. tP = 0.1. infection (UTI) in a group of boys of whom 85% had been circumcised. Investigators reporting a higher incidence 1-5 of P. mirabilis, comparable to our own, studied predominantly uncircumcised boys or failed to mention the presence or absence of foreskin. The need to relate the type of organism to circumcision on UTI is appropriate. Our data were not analyzed for the presence of foreskin, but now have been (Table). There was no difference in distribution of P. mirabilis or E. coli in the two groups. Hence, the presence of foreskin was not the determinant factor in selecting this organism in our series. The possible role of prepucial colonization by P. mirabilis and other organisms in the pathogenesis of UTI has been the subject of a few inconclusive studies?. ~ It is also not known if the foreskin affects urethral meatal flora as suggested by Dr. Cohen. Maskell et ale determined the prepucial and meatal flora of 49 boys with UTI and 51 controls. Only four circumcised subjects were included in this study, and apparently no organism(s)" was isolated from these four, or at least not mentioned. Our observations indicate the need to elucidate factor(s) other than foreskin for the variation in prevalence of P. mirabilis reported in California (Dr. Cohen) and other parts of the world. This seems important since the incidence among girls (3%), reported by Dr. Cohen previously, 7 is also much lower than found elsewhere. ~-4 It seems reasonable to speculate that" the relatively warm climate of California favors a lower incidence (2 to 3%) of P. mirabilis; the cold weather of northern areas on either side of the Atlantic seems conducive to higher incidence rates such as 23% in Norway, 3 32% Sweden) 38, 2 591 and 75%' in the United Kingdom, and 58% in New York.
Abdul J. Khan, M.D. Ramesh S. Ubriani, M.D. Edith Bombach, M.D. Melanie M. Agbayani, M.D. Harold Ratner, M.D. Hugh E. Evans, M.D. Department of Pediatrics Jewish Hospital and Medical Center of Brooklyn 555 Prospect Place Brooklyn, NY 11238 REFERENCES 1. Hallet RJ, Pead L, Muskell R: Urinary tract infection in boys, Lancet 2:1107, 1976. 2. Saxena SR, and Bassett DC: Sex related incidence in Proteus infection of urinary tract in childhood, Arch Dis Child 50:899, 1976.
Bahna SL, and Torp KH: The sex variable in childhood urinary tract infection, Acta Pediatr Scand 64:581, 1975. Mann PG: Proteus mirabilis urinary infections in childhood, J Clin Pathol 25:551, 1972. Bergstrom T: Sex differences in childhood urinary tract infections, Arch Dis Child 47:227, 1972. Maskell R, Pead L, and Hallett R J: Urinary tract pathogens in the male, Br J Urol 47:691, 1975. Cohen M: Urinary tract infection in children I. Females aged 2 through 14, first two infections, Pediatrics 50:271, 1972.
Use of dopaminefor shock in neonates To the Editor: The report by Driscoll et al' on the use ofdopamine in children seems to be carefully done; attention is given to the spectrum of responses to dopamine in various organ systems, at dose ranges from 2 to 20/~g. The authors point out that, in critically/ll infants suffering from cardiovascular collapse, the use of dopamine increases urine output, peripheral perfusion, and blood pressure. To be sure, careful attention must be paid to use of the appropriate rate of infusion. Kliegman and Fanarofl~ point out that, in a spontaneously breathing neonate, dopamine may depress peripheral chemoreceptor activity and minute volume. Even should this occur, respiratory depression would not represent a contraindication to the use of dopamine in an infant in shock; the infant could always be intubated if necessary. Kliegman and Fanaroff further state that dopamine may adversely affect pulmonary circulation by increasing pulmonary vascular resistance. No mention is made of the dopamine infusion rate at which pulmonary vasoconstriction would occur, but this effect would be observed at higher infusion rates, owing to the alpha adrenergic, norepinephrinelike property of dopamine. The beneficial effects on urine flow, gut perfusion, and blood pressure are generally observed at lower doses than those at which vasoconstriction is manifest. Kliegman and Fanaroff correctly point out that many sick neonates already have elevated pulmonary vascular resistance, resulting in persistence of the fetal circulation, and in these infants dopamine could worsen the situation. These infants should in any case be treated with Priscoline (tolazoline) given by central venous line to reduce pulmonary vasuclar resistance. Dopamine could be added to the regimen to increase urinary output, and gut and peripheral perfusion. Kliegman and Fanaroff propose the use of isoproterenol instead of dopamine, because of the presumed disadvantages of dopamine, and the ability of isoproterenol to decrease pulmonary vascular resistance. As noted, tolazoline would be an effective means to reduce the pulmonary vascular resistance. Furthermore, many animal studie# have shown that isoproterenol does not increase renal and mesenteric blood flow and in fact reduces both, by shunting of blood to skin and skeletal muscle. By the same mechanism, bypotension often results from the use of
Volume 94 Number 5
Editorial correspondence
iosproterenol, a situation clearly disastrous in the face of preexisting shock. In summary, Driscoll et al have presented data indicating the usefulness of dopamine in the treatment of shocky infants. The disadvantages pointed out by Kliegman and Fanaroff are real, but by no means contraindications to the use of dopamine. Dopamine, like all other pharmacologic agents, must be used with careful attention to dosage and possible side effects. Paul H. Volkman, M.D. Ph.D. Departments of Pediatrics and Pharmacology Loyola University Medical Center Maywood, IL 60153 REFERENCES
1. Driscoll DJ, Gillette PC, and McNamara DC: The use of dopamine in children, J PEDIATR 92:309, 1978. 2. Kliegman R, and Fanaroff AA: Caution in the use of dopamine in th e neonate, J PEDIATR 93:541, 1978 3. McNay JL, and Goldberg LI: Comparison of the effects of dopamine, isoproterenol, and norepinephrine, and bradykinin on canine renal and femoral blood flow, J Pharmacol Exp Ther 151:23, 1%6.
nepty To the Editor: As Dr. Volkman indicates, the cardiovascular response to dopamine is quite dose dependent; increased cardiac output and renal blood flow can occur at doses of the drug insufficient to cause systemic vasoconstriction. I share Dr. Kliegman's and FanaroWs L concern about using dopamine in sick neonates with cardiovascular shock and elevated pulmonary vascular resistance. Although there are unpul~lished anecdotal reports of the efficacy of tolazoline and dopamine for treatment of these infants, it would be important to document the usefulness of this therapy. David J. Driscoll, M.D. Pediatric Cardiology Texas Children's Hospital 6621 Fannin Houston, Texas 77030 REFERENCE 1. Kliegman R, and Fanaroff AA: Caution in the use of dopamine in the neonate, J PEDIATR 93:541, 1978.
Urinary catecholamines and metabolites in children To the Editor: This letter is in reference to the paper by De Schaepdryver et aP in the August issue Of THE JOURNAL. The authors state "Specimens containing tess than 1 gm creatinine/24 hours were assumed to reflect incomplete collections and were not included
853
in the study." This statement is based on studies carried out by Epstein et al.'-' Although it was not stated explicitly, it seems that these studies were performed in adults and not in children. Urinary creatinine excretion reflects muscle mass? Furthermore, calculation of normal plasma creatinine and glomerular filtration for the respective age group will demonstrate expected values of urinary creatinine well below those found by the authors. It is highly unlikely that the infants and children studied will, indeed, have urinary creatinine excretion of 1 gm and above. A more accurate determination of urinary creatinine may prove to be helpful in using urinary creatinine excretion as.a reference value in expressing urinary catecholamines excretion. Mordechay Aladjem, M.D. Pediatric Renal Unit The Chaim Sheba Medical Center, Tel-Hashomer, Israel Affiliated to the TeI-A viv University Sackler School of Medicine, Ramat-A viv REFERENCES
1. De Schaepdryver AF, Hooft C, Delbeke M J, and Van der Noortgaete M: Urinary catecholamines and metabolites in children, J I~DIATR 93:266, 1978. 2. Epstein SE, and Schriever HG: Creatinine excretion, Lancet 1:i92, 1970. 3. Black D, editor: Urinalysis and assessment of renal function, Chapter 9, in Renal disease, 3 ed, London, 1972 Blackwell Scientific Publications, p 261.
Reply To the Editor: Dr. Aladjem is perfectly right: the incriminated sentence: "Specimens... in the study," reflects our reasoning when handling 24-hour urine samples from adults and was in fact not adopted in this study: it simply is not possible to adopt this reasoning since almost all samples did not contain 1 gm creatinine/24 hours; there were a few exceptions.which contained more than 1 gm creatinine and which for this reason were not included in the study, since they in all probability reflected samples of a collection extending over more than 24 hours. Although this mistake does not invalidate the actual values reported in the paper, we apologize for this error. A. De Schaepdryver, M.D. Heymans Institute of Pharmacology University of Ghent Medical School De Pintelaan 135 B-9000 Ghent, Belgium
Differentiation of adrenal and renal carcinoma To the Editor: We read with interest the report of Andler et aP in the October, 1978, issue of THfi JOURNAL. We question the evidence presented