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Small congenital nevocellular nevi and the risk of cutaneous melanoma
ABSTRACTS mental Studias in Newborn and Two-Week-Old Piglets.
Th. A. Angerpointner, 1t. S/a/linger, O. Linderkamp, et al. Z Kinderchir 36:12-19, 1982. Circulatory adaptation to hypoxemia under anesthetic and surgical conditions was studied in newborn and 2-wk-old piglets using electromagnetic aortic flow measurement. In both hypoxic groups a prompt compensatory, statistically significant increase of cardiac performance appeared within a few minutes of hypoxemia, reaching a maximum 30 min later. Thereafter, cardiac performance decreased steadily leading to cardiac failure. Newborns survived 197 +_96 min and 2-wk-old piglets 172 +_ 128 min. Peripheral vascular resistance decreased significantly at the time of compensatory increase of cardiac performance. This compensatory increase of cardiac performance was more distinct in newborns than in two-week-old animals. Heart rate increased steadily during exposure to hypoxemia in both groups reaching a maximum 110 rain later and falling back to preexperimental values at the end of the study. Newborn normoxic control animals tolerated the experimental model significantly longer (461 _+ 167 rain; p < 0,001) than newborn hypoxic piglets. Their response pattern, however, was basically similar. Two-wk-old normoxic controls responded qualitatively identically with respect to 2-wk-old hypoxic piglets. In all four groups severe metabolic acidosis appeared during the studies, irrespective of hypoxemia or uormoxemia. Stress tolerance depended on the delta pH/hr. In both hypoxic groups stress tolerance correlated well with the increase of heart rate during bypoxemia, whereas this correlation could not be found in the normoxic controls. The authors conclude that anesthetized newborn piglets tolerate surgical stress longer than 2-wk-old animals. When they are, in addition, subjected to hypoxemia, differences disappear. The authors suspect that metaboIic conditions including oxygen transport capacity favor circulatory adaptation to stressful events better shortly after birth than during early i n f a n c y . Thomas A. Angerpointner
The Ethics of In Utero Surgery. If/. R. Barclay, R. ,4.
McCormick, J. B. Sidbury, et al. JAMA 246:1550-1552, (October), 1981. This article is one in a series of "Clinical Perspectives" which appear in the JAMA. Three of the authors have done some very interesting work with the experimental production of hydrocephalus in monkeys and its treatment by the intrauterine insertion of a metal vent which, in the monkeys, successfully prevented the development of hydrocephalus. It is the reviewer's understanding, however, that this procedure has not been successful in humans and, if it were successful, the only thing that it would treat would be hydrocephalus. However, a reader of the "Clinical Perspective" would be left with the following impressions: (1) that the intrauterine vent procedure can be done at a cost of $1,000 (less than the cost of an inguinal herniorrhaphy in Southern California), and that (2) it will prevent all the expensive care required for the management of neural tube defects, the majority of which is incurred by the cost of caring for the paralysis due to the meningocele component that the cephalic vent would not be expected to correct. The participants in the conversation go on to suggest that those doing maternal care may be held
93 legally responsible in the future for failing to see that cephalic vents are inserted in all hydrocephalic fetuses before birth. Doctor Mark Ravich's editorial, "Tell Them More," in the September 1981 Surgical Rounds, should be read as an interesting counterpoint to the above reviewed a r t i c l e . David L. Collins
INTEGUMENT AND CONNECTIVE TISSUE Small Congenital Nevocellular Nevi and the Risk of Cutaneous Melanoma, A. R. Rhodes and J. W. Melski. J Pediatr
100:219-224, (February), 1982. The relative risk of melanoma associated with small congenital nevi was estimated by comparing the published frequency of histologically documented nevocellular nevi in newborn infants with the frequency of: (1) congenital nevi at the tumor site, ascertained by history in 134 patients with melanoma; and (2) tumor-associated nevi with congenital features in 234 melanoma specimens. A 21-fold increase in melanoma risk was estimated for persons with small congenital nevi when nevi were ascertained by history; and a threeto-tenfold increase in risk when nevi were ascertained by histology. The increased risk is related presumably to the markedly increased probability of melanoma arising in association with small congenital nevi.--George Holcomb, Jr.
HEAD AND NECK Nasopharyngeal Airways in Pierre Robin Syndrome. D, P.
Heaf, P. J. Helms, R. Dinwiddie, et al. J Pediatr 100: 698-703, (May), 1982. Nasopharyngeal (NP) airways have been assessed in the management of infants with severe Pierre Robin syndrome (PRS). In 12 such infants the positioning and subsequent maintenance of these tubes were found to be important in ensuring adequate relief of the airway obstruction. In five infants measurements of lung mechanics demonstrated the benefits of NP tube placement and confirmed the observed improvements in cyanotic episodes, heart failure, electrocardiograms, and arterial gas tensions. In a retrospective survey of 40 infants with PRS, failure to thrive was found to be significantly correlated with the severity of the airflow obstruction. This failure to thrive was reversed in the infants managed with NP tubes in comparison with an age-matched group nursed while prone. The lack of significant complications with the NP airway and its acceptability to nursing staff, patients, and their parents suggest that this method deserves more widespread use in PRS and perhaps in other situations in which high upper respiratory tract obstruction is predominant.--George Holcomb, Jr.
THORAX A Dual Approach to Tracheohronchial Foreign Bodies in Children. D. N. Campbell, E. K. Cotton, and J. R. Lilly.
Surgery 91:178-182, (February), 1982. Fifty-seven children were treated for foreign body aspiration, Twenty-nine patients had a foreign body in the trachea or mainstem bronchus which the authors arbitrarily designated central in location. Objects trapped distal to the mainstem bronchus were designated peripheral and occurred in 28 patients. The interval between foreign body aspiration
Th. A. Angerpointner, 1t. S/a/linger, O. Linderkamp, et al. Z Kinderchir 36:12-19, 1982. Circulatory adaptation to hypoxemia under anesthetic and surgical conditions was studied in newborn and 2-wk-old piglets using electromagnetic aortic flow measurement. In both hypoxic groups a prompt compensatory, statistically significant increase of cardiac performance appeared within a few minutes of hypoxemia, reaching a maximum 30 min later. Thereafter, cardiac performance decreased steadily leading to cardiac failure. Newborns survived 197 +_96 min and 2-wk-old piglets 172 +_ 128 min. Peripheral vascular resistance decreased significantly at the time of compensatory increase of cardiac performance. This compensatory increase of cardiac performance was more distinct in newborns than in two-week-old animals. Heart rate increased steadily during exposure to hypoxemia in both groups reaching a maximum 110 rain later and falling back to preexperimental values at the end of the study. Newborn normoxic control animals tolerated the experimental model significantly longer (461 _+ 167 rain; p < 0,001) than newborn hypoxic piglets. Their response pattern, however, was basically similar. Two-wk-old normoxic controls responded qualitatively identically with respect to 2-wk-old hypoxic piglets. In all four groups severe metabolic acidosis appeared during the studies, irrespective of hypoxemia or uormoxemia. Stress tolerance depended on the delta pH/hr. In both hypoxic groups stress tolerance correlated well with the increase of heart rate during bypoxemia, whereas this correlation could not be found in the normoxic controls. The authors conclude that anesthetized newborn piglets tolerate surgical stress longer than 2-wk-old animals. When they are, in addition, subjected to hypoxemia, differences disappear. The authors suspect that metaboIic conditions including oxygen transport capacity favor circulatory adaptation to stressful events better shortly after birth than during early i n f a n c y . Thomas A. Angerpointner
The Ethics of In Utero Surgery. If/. R. Barclay, R. ,4.
McCormick, J. B. Sidbury, et al. JAMA 246:1550-1552, (October), 1981. This article is one in a series of "Clinical Perspectives" which appear in the JAMA. Three of the authors have done some very interesting work with the experimental production of hydrocephalus in monkeys and its treatment by the intrauterine insertion of a metal vent which, in the monkeys, successfully prevented the development of hydrocephalus. It is the reviewer's understanding, however, that this procedure has not been successful in humans and, if it were successful, the only thing that it would treat would be hydrocephalus. However, a reader of the "Clinical Perspective" would be left with the following impressions: (1) that the intrauterine vent procedure can be done at a cost of $1,000 (less than the cost of an inguinal herniorrhaphy in Southern California), and that (2) it will prevent all the expensive care required for the management of neural tube defects, the majority of which is incurred by the cost of caring for the paralysis due to the meningocele component that the cephalic vent would not be expected to correct. The participants in the conversation go on to suggest that those doing maternal care may be held
93 legally responsible in the future for failing to see that cephalic vents are inserted in all hydrocephalic fetuses before birth. Doctor Mark Ravich's editorial, "Tell Them More," in the September 1981 Surgical Rounds, should be read as an interesting counterpoint to the above reviewed a r t i c l e . David L. Collins
INTEGUMENT AND CONNECTIVE TISSUE Small Congenital Nevocellular Nevi and the Risk of Cutaneous Melanoma, A. R. Rhodes and J. W. Melski. J Pediatr
100:219-224, (February), 1982. The relative risk of melanoma associated with small congenital nevi was estimated by comparing the published frequency of histologically documented nevocellular nevi in newborn infants with the frequency of: (1) congenital nevi at the tumor site, ascertained by history in 134 patients with melanoma; and (2) tumor-associated nevi with congenital features in 234 melanoma specimens. A 21-fold increase in melanoma risk was estimated for persons with small congenital nevi when nevi were ascertained by history; and a threeto-tenfold increase in risk when nevi were ascertained by histology. The increased risk is related presumably to the markedly increased probability of melanoma arising in association with small congenital nevi.--George Holcomb, Jr.
HEAD AND NECK Nasopharyngeal Airways in Pierre Robin Syndrome. D, P.
Heaf, P. J. Helms, R. Dinwiddie, et al. J Pediatr 100: 698-703, (May), 1982. Nasopharyngeal (NP) airways have been assessed in the management of infants with severe Pierre Robin syndrome (PRS). In 12 such infants the positioning and subsequent maintenance of these tubes were found to be important in ensuring adequate relief of the airway obstruction. In five infants measurements of lung mechanics demonstrated the benefits of NP tube placement and confirmed the observed improvements in cyanotic episodes, heart failure, electrocardiograms, and arterial gas tensions. In a retrospective survey of 40 infants with PRS, failure to thrive was found to be significantly correlated with the severity of the airflow obstruction. This failure to thrive was reversed in the infants managed with NP tubes in comparison with an age-matched group nursed while prone. The lack of significant complications with the NP airway and its acceptability to nursing staff, patients, and their parents suggest that this method deserves more widespread use in PRS and perhaps in other situations in which high upper respiratory tract obstruction is predominant.--George Holcomb, Jr.
THORAX A Dual Approach to Tracheohronchial Foreign Bodies in Children. D. N. Campbell, E. K. Cotton, and J. R. Lilly.
Surgery 91:178-182, (February), 1982. Fifty-seven children were treated for foreign body aspiration, Twenty-nine patients had a foreign body in the trachea or mainstem bronchus which the authors arbitrarily designated central in location. Objects trapped distal to the mainstem bronchus were designated peripheral and occurred in 28 patients. The interval between foreign body aspiration