301
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Lacaze-Masmonteil T, Feldmann D, Walti H, Bourbon J. [Neonatal pulmonary alveolar proteinosis and SP-B deficiency: pulmonary surfactant at the time of molecular pathology]. Arch Pediatr 1996; 3:309-12. [PMID: 8762949 DOI: 10.1016/0929-693x(96)84682-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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302
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Hudak ML, Farrell EE, Rosenberg AA, Jung AL, Auten RL, Durand DJ, Horgan MJ, Buckwald S, Belcastro MR, Donohue PK, Carrion V, Maniscalco WW, Balsan MJ, Torres BA, Miller RR, Jansen RD, Graeber JE, Laskay KM, Matteson EJ, Egan EA, Brody AS, Martin DJ, Riddlesberger MM, Montgomery P. A multicenter randomized, masked comparison trial of natural versus synthetic surfactant for the treatment of respiratory distress syndrome. J Pediatr 1996; 128:396-406. [PMID: 8774514 DOI: 10.1016/s0022-3476(96)70291-3] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To compare the efficacy and safety of two surfactant preparations in the treatment of respiratory distress syndrome (RDS). METHODS We conducted a randomized, masked comparison trial at 21 centers. Infants with RDS who were undergoing mechanical ventilation were eligible for treatment with two doses of either a synthetic (Exosurf) or natural (Infasurf) surfactant if the ratio of arterial to alveolar partial pressure of oxygen was less than or equal to 0.22. Crossover treatment was allowed within 96 hours of age if severe respiratory failure (defined as two consecutive arterial/alveolar oxygen tension ratios < or = 0.10) persisted after two doses of the randomly assigned surfactant. Four primary outcome measures of efficacy (the incidence of pulmonary air leak (< or = 7 days); the severity of RDS; the incidence of death from RDS; and the incidence of survival without bronchopulmonary dysplasia (BPD) at 28 days after birth) were compared by means of linear regression techniques. RESULTS The primary analysis of efficacy was performed in 1033 eligible infants and an analysis of safety outcomes in the 1126 infants who received study surfactant. Preentry demographic characteristics and respiratory status were similar for the two treatment groups, except for a small but significant difference in mean gestational age (0.5 week) that favored the infasurf treatment group. Pulmonary air leak (< or = 7 days) occurred in 21% of Exosurf- and 11% of infasurf-treated infants (adjusted relative risk, 0.53; 95% confidence interval, 0.40 to 0.71; p < or = 0.0001). During the 72 hours after the initial surfactant treatment, the average fraction of inspired oxygen (+/-SEM) was 0.47 +/- 0.01 for Exosurf- and 0.39 +/- 0.01 for infasurf-treated infants (difference, 0.08; 95% confidence interval, 0.06 to 0.10; p < 0.0001); the average mean airway pressure (+/-SEM) was 8.6 +/- 0.1 cm H2O; for Exosurf- and 7.2 +/- 0.1 cm H2O for Infasurf-treated infants (difference, 1.4 cm H2O; 95% confidence interval, 1.0 to 1.8 cm H2O; p < 0.0001). The incidences of RDS-related death, total respiratory death, death to discharge, and survival without bronchopulmonary dysplasia at 28 days after birth did not differ. The number of days of more than 30% inspired oxygen and of assisted ventilation, but not the duration of hospitalization, were significantly lower in Infasurf-treated infants. CONCLUSION Compared with Exosurf, Infasurf provided more effective therapy for RDS as assessed by significant reductions in the severity of respiratory disease and in the incidence of air leak complications.
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Affiliation(s)
- M L Hudak
- Department of Pediatrics, Children's Hospital of Buffalo, State University of New York, USA
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303
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Wiedemann HP. Surfactant and acquired lung diseases. THE JOURNAL OF LABORATORY AND CLINICAL MEDICINE 1996; 127:239-41. [PMID: 9273354 DOI: 10.1016/s0022-2143(96)90089-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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304
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Hummler E, Barker P, Gatzy J, Beermann F, Verdumo C, Schmidt A, Boucher R, Rossier BC. Early death due to defective neonatal lung liquid clearance in alpha-ENaC-deficient mice. Nat Genet 1996; 12:325-8. [PMID: 8589728 DOI: 10.1038/ng0396-325] [Citation(s) in RCA: 661] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The amiloride-sensitive epithelial sodium channel, ENaC, is a heteromultimeric protein made up of three homologous subunits (alpha, beta and gamma) (1,2). In vitro, assembly and expression of functional active sodium channels in the Xenopus oocyte is strictly dependent on alpha-ENaC--the beta and gamma subunits by themselves are unable to induce an amiloride-sensitive sodium current in this heterologous expression system (2). In vivo, ENaC constitutes the limiting step for sodium absorption in epithelial cells that line the distal renal tubule, distal colon and the duct of several exocrine glands. The adult lung expresses alpha, beta and gamma ENaC (3,4), and an amiloride-sensitive electrogenic sodium reabsorption has been documented in upper and lower airways (3-7), but it is not established whether this sodium transport is mediated by ENaC in vivo. We inactivated the mouse alpha-ENaC gene by gene targeting. Amiloride-sensitive electrogenic Na+ transport was abolished in airway epithelia from alpha-ENaC(-/-) mice. Alpha-ENaC(-/-) neonates developed respiratory distress and died within 40 h of birth from failure to clear their lungs of liquid. This study shows that ENaC plays a critical role in the adaptation of the newborn lung to air breathing.
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Affiliation(s)
- E Hummler
- Institut de Pharmacologie et de Toxicologie de l'Université, Lausanne, Switzerland
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305
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Tashiro K, Yamada K, Li WZ, Matsumoto Y, Kobayashi T. Aerosolized and instilled surfactant therapies for acute lung injury caused by intratracheal endotoxin in rats. Crit Care Med 1996; 24:488-94. [PMID: 8625639 DOI: 10.1097/00003246-199603000-00020] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
OBJECTIVE To compare the effects of surfactant replacement by aerosol inhalation and bolus instillation on acute lung injury caused by the intratracheal injection of endotoxin in rats. DESIGN Prospective, randomized study. SETTING University Laboratory. SUBJECTS Male Wistar rats weighing 368 +/- 31 (SD) g. INTERVENTIONS Escherichia coli endotoxin (57 +/- 20 mg/kg) was injected into the tracheas of 36 anesthetized and mechanically ventilated rats (FIO of 1.0). When the PaO2 had decreased to <200 torr (<26.7 kPa), the rats were randomly assigned to one of three groups: a control group (n=12)given no material; a bolus group (n=12) given a modified natural surfactant suspension (100 mg/kg in 2.0 mL/kg saline) by bolus instillation into the trachea; and an aerosol group (n=12) given surfactant aerosolized with an ultra-sonic nebulizer for 60 mins. MEASUREMENTS AND MAIN RESULTS Bolus instillation transiently decreased the mean blood pressure by approximately 30%. However, aerosol inhalation did not. The PaO2 values of the control group remained <90 torr (<12.0 kPa) until the end of the experiment (180 mins). In contrast, the PaO2 of the bolus group increased to 387 +/- 134 torr (51.6 +/- 17.9 kPa; p<.05 vs. other groups) 15 mins after surfactant replacement, and remained at approximately 400 torr (approximately 53.3 kPa) throughout the experiment. The PaO2 values of the aerosol group increased slowly, peaked at 240 +/- 109 torr (32.0 +/- 14.5 kPa; p<.05 vs. the control group) 60 mins after the start of surfactant replacement, and remained at approximately 200 torr (approximately 26.7 kPa). CONCLUSIONS Bolus instillation was superior to aerosol inhalation concerning maximum efficacy, the rapid onset of therapeutic effects, and the necessary dose of surfactant. However, aerosol that does not cause hypotension may be of use in the treatment of adult respiratory distress syndrome in patients with circulatory instability.
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Affiliation(s)
- K Tashiro
- Department of Anesthesiology and Intensive Care Medicine, School of Medicine, Kanazawa University, Japan
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306
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Walti H. [Natural or artificial surfactants? Arguments in favour of natural surfactants]. Arch Pediatr 1996; 3:165-75. [PMID: 8785540 DOI: 10.1016/0929-693x(96)85071-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The use of exogenous surfactant (ES) is an essential component for prevention and treatment of hyaline membrane disease (HMD). The ES available for clinical use are of two therapeutic classes: natural surfactants prepared from mammalian lung and artificial surfactants. The choice between these two classes of ES is controversial. In this overview, we present the arguments in favour of the preferential use of natural ES. The presence of hydrophobic specific proteins (SP-B and SP-C) provides to natural ES better surface tension properties than artificial ES. The in vitro greater efficacy of natural ES has been confirmed in vivo in experimental models of surfactant deficiency, human pharmacodynamic studies, and comparative clinical trials. Furthermore, the excellent clinical tolerance and harmlessness of natural ES has been firmly established. A meta-analysis of the comparative clinical trials between natural ES and one artificial ES (enrolling as many as 4400 babies treated for HMD) suggests that the use of natural ES compared to this artificial ES significantly reduces the neonatal mortality by 20%. In conclusion, all these arguments are in favor of the preferential use of natural ES for prevention and treatment of HMD.
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Affiliation(s)
- H Walti
- Service de médecine néonatale, hôpital Cochin-Port-Royal, Paris, France
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307
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Bevilacqua G, Parmigiani S, Robertson B. Prophylaxis of respiratory distress syndrome by treatment with modified porcine surfactant at birth: a multicentre prospective randomized trial. J Perinat Med 1996; 24:609-20. [PMID: 9120744 DOI: 10.1515/jpme.1996.24.6.609] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The objective of this prospective, multicentre trial, carried out at 18 third level hospitals in Italy, was to evaluate efficacy of modified porcine surfactant (Curosurf), administered at birth to prevent the development of respiratory distress syndrome (RDS) in premature infants. 287 babies with a gestational age of 24-30 weeks were randomized to prophylactic treatment with Curosurf (80 mg/ml; dose 20 mg/kg) or to a control group receiving no surfactant treatment in the delivery-room. Babies in both groups were eligible for rescue treatment with surfactant (200 mg/kg) if they developed clinical symptoms of RDS and required mechanical ventilation. The main end-point was to obtain, in the prophylaxis group, a 30% reduction in the incidence of grade 3-4 RDS. Median gestational age was 28 weeks in both groups and mean birth weight 1010 and 1002 g, respectively for prophylaxis and control babies. There was a 32% reduction in the incidence of grade 3-4 RDS in the prophylaxis group (p < 0.05). This was associated with a significant reduction in mean maximum fraction of inspired oxygen (0.57 vs 0.66%; p < 0.01), a decreased incidence of pulmonary interstitial emphysema (7 vs 14%; p < 0.05) and a lowered mortality (21 vs 35%; p < 0.01). Combined unfavourable outcome (mortality + bronchopulmonary dysplasia and/or grade 3-4 intraventricular hemorrhage and/or grade 2-4 retinopathy of prematurity) was significantly lower in the prophylaxis than in the second group (41 vs 58%; p < 0.01). The favourable effects of prophylactic treatment were equally recorded in all the age groups, including the babies with the lowest gestational age (24-25 weeks). Multiple and logistic regression analysis confirmed that high gestational age and surfactant prophylaxis were, independently, associated with a lower degree of RDS (p = 0.0001 and p = 0.0008, respectively) and a lower mortality (p = 0.0001 and p = 0.0045, respectively). We conclude that prophylaxis with modified natural surfactant effectively prevents RDS in newborn babies between 24 and 30 weeks' gestation.
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Affiliation(s)
- G Bevilacqua
- Institute of Child Health and Neonatal Medicine, University of Parma, Italy
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308
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Affiliation(s)
- M Haas
- Division of Neonatology, Children's Hospital Medical Center, Cincinnati, OH 45229-3039, USA
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309
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Abstract
OBJECTIVE To review the pathophysiology, epidemiology, and therapy of patients with acute respiratory distress syndrome (ARDS). DATA SOURCES Articles pertaining to the pathophysiology, epidemiology, and supportive therapy of ARDS were chosen from a computerized literature search. Recent review articles addressing the specifics of treatment in an intensive care unit are cited rather than restating these specific aspects. DATA EXTRACTION Primary literature was chosen in reference to the pathophysiology, epidemiology, and supportive therapy of ARDS. Both human and animal studies were included. Review articles were cited regarding areas of ARDS supportive therapy rather than citing the primary literature. STUDY SELECTION Only peer-reviewed primary literature sources were chosen to describe the specifics of pathophysiology and epidemiology. When human data were unavailable, animal studies were cited. Recent review articles were cited for specifics on supportive therapy. DATA SYNTHESIS Consensus regarding the definition of ARDS and the difficulties of performing large controlled trials in patients with ARDS has made development of new modalities problematic. Understanding the underlying pathophysiology and risk factors for mortality are key to supportive therapy. Although many pharmacologic agents are being tested in patients with ARDS, attention to the aspects of supportive therapy is the only method to decrease mortality. CONCLUSION The mortality of ARDS continues to be 70%. Pharmacists can play an active role in the supportive therapy of patients with ARDS, which is currently the only way to impact mortality.
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Affiliation(s)
- S M Watling
- Department of Medicine, University of Missouri, Columbia 65212, USA
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310
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311
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Wei Y, Yarus S, Greenberg NM, Whitsett J, Rosen JM. Production of human surfactant protein C in milk of transgenic mice. Transgenic Res 1995; 4:232-40. [PMID: 7655513 DOI: 10.1007/bf01969116] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Respiratory distress syndrome (RDS), caused by lack of pulmonary surfactant, affects 65 000 infants annually in the USA. Surfactant replacement therapy reduces the morbidity and mortality associated with RDS. Human surfactant protein C (SP-C) is an important component of pulmonary surfactant. To produce human SP-C, a construct using the rat whey acidic protein (WAP) promoter and 3' untranslated regions to target expression of the human SP-C gene to the mammary gland of transgenic mice was created. WAP/SP-C mRNA expression was detected in all transgenic lines analysed. SP-C was expressed in a copy-number-dependent and integration-site-independent fashion, with levels of expression ranging from 0.01% to 36.0% of the endogenous mouse WAP mRNA, and WAP/SP-C mRNA expression levels were greater than those of of the endogenous mouse lung SP-C mRNA. Expression at the RNA level was specific to the mammary gland and paralleled the endogenous WAP expression pattern during mammary gland development. Expression and secretion of the SP-C protein in the lactating mammary gland was demonstrated by western blots performed on whole milk using an anti-SP-C polyclonal antibody. Immunoreactive proteins of MW 22 and 12-14 kDa appeared only in transgenic milk. The 22 kDa protein represents the proprotein, and the 12-14 kDa is a processed form of SP-C.
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Affiliation(s)
- Y Wei
- Department of Cell Biology, Baylor College of Medicine, Houston, TX 77030, USA
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312
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Border JR. Death from severe trauma: open fractures to multiple organ dysfunction syndrome. THE JOURNAL OF TRAUMA 1995; 39:12-22. [PMID: 7636902 DOI: 10.1097/00005373-199507000-00002] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- J R Border
- Department of Surgery, University at Buffalo, Erie County Medical Center, New York 14215, USA
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313
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Kliegman RM. Neonatal technology, perinatal survival, social consequences, and the perinatal paradox. Am J Public Health 1995; 85:909-13. [PMID: 7604911 PMCID: PMC1615530 DOI: 10.2105/ajph.85.7.909] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Exogenous surfactant therapy for premature infants with respiratory distress syndrome has had a significant impact on infant mortality and on some complications of prematurity. Yet the total number of low-birthweight infants has not declined, resulting in a high-risk population who would require surfactant therapy and long-term child care. Surviving low-birthweight infants (despite surfactant therapy) remain at risk for the consequences of premature birth, such as neurosensory impairment, cerebral palsy, and chronic lung disease. In addition, because of the close association between poverty and low birthweight, surviving premature infants are at increased risk for the new morbidities such as violence, homelessness, child abuse and neglect, and addictive drug use. A goal should be to reduce the risk of being born with a low birthweight, rather than having to treat the consequences of premature gestation. Despite the marvelous advances that permit us to treat respiratory distress syndrome, the continuing high low-birthweight rate places a significant strain on our health care system. The goal should be redirected to identifying large population-based efforts to reduce the number of low-birthweight infants.
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Affiliation(s)
- R M Kliegman
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee 53226, USA
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314
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Anwar MU, Clark RH. Section Review: Prevention and treatment of respiratory distress syndrome: Pulmonary-Allergy, Dermatological, Gastrointestinal & Arthritis. Expert Opin Investig Drugs 1995. [DOI: 10.1517/13543784.4.7.581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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315
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Lázár G, Lázár G, Husztik E, Duda E, Agarwal MK. The influence of antiglucocorticoids on stress and shock. Ann N Y Acad Sci 1995; 761:276-95. [PMID: 7625726 DOI: 10.1111/j.1749-6632.1995.tb31384.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- G Lázár
- Institute of Pathophysiology, Albert Szent-Györgyi Medical University, Hungary
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316
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Corbet A, Gerdes J, Long W, Avila E, Puri A, Rosenberg A, Edwards K, Cook L. Double-blind, randomized trial of one versus three prophylactic doses of synthetic surfactant in 826 neonates weighing 700 to 1100 grams: effects on mortality rate. American Exosurf Neonatal Study Groups I and IIa. J Pediatr 1995; 126:969-78. [PMID: 7776110 DOI: 10.1016/s0022-3476(95)70226-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
At 33 hospitals in the United States, a double-blind, randomized clinical trial was performed to compare one versus three prophylactic doses of synthetic surfactant in 700 to 1100 gm inborn infants. All 826 infants received an initial prophylactic dose of surfactant within 30 minutes of birth. Subsequently 410 infants received two doses of placebo (air) 12 and 24 hours later, and 416 infants received two additional doses of surfactant. By the age of 28 days, 70 infants who received one dose of surfactant and 40 infants who received three doses were dead, a 43% relative reduction in the mortality rate (30 fewer deaths; p = 0.002). By the age of 1 year after term, 87 infants who received one dose and 62 infants who received three doses were dead: a 29% relative reduction in the mortality rate (25 fewer deaths; p = 0.027). Infants who received three doses of surfactant required significantly less oxygen and less mean airway pressure for the first week of life. Necrotizing enterocolitis (9 vs 25 infants; p = 0.005), and use of high-frequency ventilation (13 vs 26 infants; p = 0.037); pancuronium (43 vs 62 infants; p = 0.045); and leukocyte transfusions (0 vs 4 infants; p = 0.042) were less frequent in the three-dose group, but air leak, bronchopulmonary dysplasia, intraventricular hemorrhage, patent ductus arteriosus, pulmonary hemorrhage, and infections were not different. These results indicate that physiologic findings, mortality rates, and probably morbidity rates are improved by two additional prophylactic doses of synthetic surfactant.
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Affiliation(s)
- A Corbet
- Department of Pediatrics, Emory University, Atlanta, Georgia, USA
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317
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Kinsella JP, Abman SH. Recent developments in the pathophysiology and treatment of persistent pulmonary hypertension of the newborn. J Pediatr 1995; 126:853-64. [PMID: 7776084 DOI: 10.1016/s0022-3476(95)70197-4] [Citation(s) in RCA: 172] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Successful management of severe PPHN depends on the application of appropriate strategies to manage the cardiopulmonary interactions that characterize this syndrome. Manifestations of PPHN often involve dysfunctional pulmonary vasoregulation, with suprasystemic pulmonary vascular resistance causing extrapulmonary shunting, pulmonary parenchymal disease causing intrapulmonary shunting, and systemic hemodynamic deterioration. Inhaled NO can cause marked improvement in oxygenation when optimal lung inflation is achieved and systemic blood volume and vascular resistance are adequate. Although concern has been expressed regarding potential increases in costs associated with this new therapy, we have found that the successful application of inhaled NO in PPHN has reduced costs of hospitalization and duration of hospital stay by approximately 50% and 40%, respectively. However, inhaled NO alone is unlikely to cause sustained improvement in oxygenation in neonatal hypoxemic respiratory failure associated with severe parenchymal lung disease without extrapulmonary shunting. Inhaled NO may be an important tool in the management of severe PPHN when its application is limited to patients with severe extrapulmonary shunting and vigilant attention is given to changes in the clinical course.
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Affiliation(s)
- J P Kinsella
- Department of Pediatrics, Children's Hospital, Denver, CO 80218-1088, USA
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318
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Walther FJ, Mullett M, Schumacher R, Sundell H, Easa D, Long W. One-year follow-up of 66 premature infants weighing 500 to 699 grams treated with a single dose of synthetic surfactant or air placebo at birth: results of a double-blind trial. American Exosurf Neonatal Study Group I. J Pediatr 1995; 126:S13-9. [PMID: 7745506 DOI: 10.1016/s0022-3476(95)70003-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
In a multicenter, double-blind, placebo-controlled trial that enrolled 215 premature infants with birth weights of 500 to 699 gm, 106 infants were treated prophylactically with a single 5 ml/kg dose of synthetic surfactant and 109 infants were given an equivalent dose of air placebo shortly after birth. In each group, 40 children survived infancy: 36 children in the air placebo group and 30 children in the synthetic surfactant group were available for follow-up. Weight, height, and head circumference measurements were similar for both groups at 1-year adjusted age. Infants who received synthetic surfactant at birth had statistically similar Bayley Scales of Infant Development scores (mental developmental index, 92 vs 83; psychomotor developmental index, 87 vs 82) compared with controls. Mild to moderate impairments in the synthetic surfactant group were 7% versus 29% in the control group; these differences were not statistically significant. The incidence of retinopathy of prematurity, the number of hospital readmissions, the need for surgery after day 28, evidence of chronic lung disease, the need for respiratory support at 1-year adjusted age, and the incidence of allergies were also not different between the two groups. However, the proportion of infants surviving without impairment was modestly higher in the synthetic surfactant group (8%, air placebo group; 23%, synthetic surfactant group). The findings from this small study indicate that infants weighing 500 to 699 gm who receive a single prophylactic dose of synthetic surfactant at birth have neurodevelopmental outcomes at least equivalent to those of infants given air placebo at 1-year follow-up.
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Affiliation(s)
- F J Walther
- Department of Pediatrics, King/Drew Medical Center, Los Angeles, CA 90059, USA
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319
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Affiliation(s)
- W Long
- Department of Pediatrics, School of Medicine, University of North Carolina at Chapel Hill 27599-7220, USA
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320
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Sell M, Cotton R, Hirata T, Guthrie R, LeBlanc M, Mammel M, Long W. One-year follow-up of 273 infants with birth weights of 700 to 1100 grams after prophylactic treatment of respiratory distress syndrome with synthetic surfactant or air placebo. American Exosurf Neonatal Study Group I. J Pediatr 1995; 126:S20-5. [PMID: 7745507 DOI: 10.1016/s0022-3476(95)70004-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A single dose of synthetic surfactant was administered prophylactically to premature neonates with birth weights between 700 and 1100 gm. The effects of this treatment on neurodevelopmental, neurologic, and ophthalmologic outcomes, impairments, and general health status were examined during a follow-up evaluation at 1-year adjusted age. The study was a multicenter, parallel, randomized, double-blind comparison of 446 infants who received either air placebo (n = 222) or synthetic surfactant (n = 224). Follow-up evaluations were completed for 82% of surviving infants in both treatment groups. Neurodevelopmental outcome and growth were equivalent in the infants treated with synthetic surfactant and in the infants given air placebo. Impairments occurred in 38% of the infants treated with air placebo compared with 31% of those given synthetic surfactant; the difference was not statistically significant (relative risk 0.809, 95% confidence interval 0.585, 1.119). The incidence of asthma was significantly higher in the group of infants given air placebo (4% vs 10% for surfactant and air placebo, respectively, relative risk 0.391, 95% confidence intervals 0.157, 0.972). Other outcomes, including retinopathy of prematurity, hospital readmissions, surgery, and evidence of chronic lung disease, were not different. Administration of a single prophylactic dose of synthetic surfactant increases survival in infants with birth weights between 700 and 110 gm without increasing the number or proportion of impaired survivors.
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Affiliation(s)
- M Sell
- Department of Pediatrics, St. Luke's Regional Medical Center, Boise, Idahd, USA
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321
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Saigal S, Robertson C, Sankaran K, Bingham W, Casiro O, MacMurray B, Whitfield M, Long W. One-year outcome in 232 premature infants with birth weights of 750 to 1249 grams and respiratory distress syndrome randomized to rescue treatment with two doses of synthetic surfactant or air placebo. Canadian Exosurf Neonatal Study Group. J Pediatr 1995; 126:S61-7. [PMID: 7745513 DOI: 10.1016/s0022-3476(95)70009-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A randomized, double-blind, placebo-controlled trial was performed in 13 hospitals in Canada to assess whether two rescue doses of a synthetic surfactant (Exosurf Neonatal) would reduce mortality and morbidity rates in neonates with respiratory distress syndrome who weighed from 750 to 1249 gm. As part of the original trial design, double-blind follow-up evaluations were performed at 1-year adjusted age. A total of 118 patients who received air placebo and 114 patients who received synthetic surfactant were evaluated at 1 year. Growth and development in the two groups were equivalent. Scores on the Bayley Scales of Infant Development were within the normal range for both groups (mental development index, 90 +/- 22 vs 92 +/- 22; psychomotor development index, 81 +/- 19 vs 87 +/- 22 for the air placebo and synthetic surfactant groups, respectively). However, in both groups the proportion of infants with any impairment (air placebo group, 43 of 118 (36%); synthetic surfactant group, 41 of 114 (36%) and severe impairment (air placebo group, 29 of 118 (25%); synthetic surfactant group, 21 of 114 (18%)) was substantial. We conclude that two rescue doses of synthetic surfactant in infants with RDS who weighed 750 to 1249 gm had no detrimental effect on developmental outcome or late morbidity. No long-term benefits to 12-months corrected age were observed with the use of surfactant in this weight class. Larger studies or meta-analyses of existing trials will be required to determine if there are any late outcome advantages associated with rescue use of synthetic surfactant in infants weighing 700 to 1249 gm.
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Affiliation(s)
- S Saigal
- Children's Hospital, McMaster University, Hamilton, Ontario, Canada
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322
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Courtney SE, Long W, McMillan D, Walter D, Thompson T, Sauve R, Conway B, Bard H. Double-blind 1-year follow-up of 1540 infants with respiratory distress syndrome randomized to rescue treatment with two doses of synthetic surfactant or air in four clinical trials. American and Canadian Exosurf Neonatal Study Groups. J Pediatr 1995; 126:S43-52. [PMID: 7745510 DOI: 10.1016/s0022-3476(95)70007-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Synthetic surfactant has been shown to reduce neonatal and 1-year mortality and neonatal morbidity in infants with respiratory distress syndrome. However, less is known about the effects of synthetic surfactant on developmental outcome and long-term morbidity. Four multicenter, randomized, placebo-controlled trials of synthetic surfactant administered as rescue therapy were conducted in the United States and Canada, with a total enrollment of 2224 patients. Double-blind developmental evaluations of survivors were conducted at 1 year of age (adjusted for prematurity) in all four trials. Of the 1802 patients enrolled in the placebo-controlled rescue trials who survived to 1 year, 1540 (85%) completed the 1-year follow-up evaluation. Height, weight, and head circumference measurements were not different in the treatment and control groups. Mean and median Bayley Scores of Infant Development for both the Mental Development Index and the Psychomotor Development Index were also equivalent. The incidence of impairments was not different in the two groups (mild to moderate impairment, 12% (92 of 745) for the air placebo group vs 11% (86 of 771) for the synthetic surfactant group; severe impairment, 15% (114 of 745) for the air placebo group vs 13% (102 of 771) for the synthetic surfactant group). No differences in rates of retinopathy of prematurity or hearing impairment were found in the treatment groups. The need for surgery after day 28 of life (relative risk, 0.779; 95% confidence interval, 0.665, 0.927) and the need for respiratory support at 1 year (relative risk, 0.525; 95% confidence intervals, 0.303, 0.911) were both reduced in the synthetic surfactant group. These results indicate that developmental outcome at 1 year of age is at least as good among infants with respiratory distress syndrome who received rescue therapy with synthetic surfactant as it is in infants who received air placebo; the results also indicate that the incidence of long-term morbidity is reduced.
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Affiliation(s)
- S E Courtney
- Department of Pediatrics, Children's Medical Center, Dayton, Ohio, USA
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323
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Temmesfeld-Wollbrück B, Walmrath D, Grimminger F, Seeger W. Prevention and therapy of the adult respiratory distress syndrome. Lung 1995; 173:139-64. [PMID: 7616757 DOI: 10.1007/bf00175656] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The complex pathophysiology of adult respiratory distress syndrome (ARDS) makes preventive and therapeutic concepts difficult. Ample experimental evidence indicates that ARDS can be prevented by blocking systemic inflammatory agents. Clinically, only heparin, for inhibition of coagulation phenomena, is presently used among this array of approaches. Corticosteroids have not proven to be beneficial in ARDS. Alternative antiinflammatory agents are being proposed and are under current clinical investigation (e.g. indomethacin, acetylcysteine, alpha 1-proteinase inhibitor, antitumor necrosis factor, interleukin 1 receptor antagonist, platelet-activating factor antagonists). Symptomatic therapeutic strategies in early ARDS include selective pulmonary vasodilation (preferably by inhaled vasorelaxant agents) and optimal fluid balance. Transbronchial surfactant application, presently tested in pilot studies, may be available for ARDS patients in the near future and may have acute beneficial effects on gas exchange, pulmonary mechanics, and lung hemodynamics; its impact on survival cannot be predicted at the present time. Strong efforts should be taken to reduce secondary nosocomial pneumonia in ARDS patients and thus avoid the vicious circle of pneumonia, sepsis from lung infection, and perpetuation of multiple organ dysfunction syndrome. Optimal respirator therapy should be directed to ameliorate gas-exchange conditions acutely but at the same time should aim at minimizing potentially aggravating side effects of artificial ventilation (barotrauma, O2 toxicity). Several new techniques of mechanical ventilation and the concept of permissive hypercapnia address these aspects. Approaches with extracorporeal CO2 removal and oxygenation are being used in specialized centers.
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324
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Smyth J, Allen A, MacMurray B, Peliowski A, Sankaran K, Volberg F, Shukla A, Long W. Double-blind, randomized, placebo-controlled Canadian multicenter trial of two doses of synthetic surfactant or air placebo in 224 infants weighing 500 to 749 grams with respiratory distress syndrome. Canadian Exosurf Neonatal Study Group. J Pediatr 1995; 126:S81-9. [PMID: 7745516 DOI: 10.1016/s0022-3476(95)70012-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
In a multicenter, double-masked, placebo-controlled rescue trial conducted at 12 Canadian hospitals, two 5 ml/kg doses of a synthetic surfactant or air placebo were administered to 224 infants with birth weights of 500 to 749 gm who had established respiratory distress syndrome and an arterial/alveolar oxygen tension ratio of less than 0.22. The first dose was given between 2 and 24 hours of age; the second dose was given 12 hours later to the infants continuing to receive mechanical ventilation. Infants were stratified at study entry by birth weight and gender. Infants receiving synthetic surfactant showed significant improvements in alveolar-arterial oxygen tension gradient, arterial/alveolar oxygen tension ratio, and oxygen and ventilator requirements through day 7. In the group randomized to synthetic surfactant, significant improvements were seen in oxygen requirements at the first time point measured (2 hours; p = 0.02), in the alveolar-arterial oxygen tension gradient by the second time point measured (6 hours; p = 0.03), and in mean airway pressure after 6 hours. Overall mortality at 28 days was not significantly different in the two groups (50% vs 46%, air placebo group vs synthetic surfactant group; p = 0.586). Similarly, neither the incidence of bronchopulmonary dysplasia (37% vs 30%, air placebo group vs synthetic surfactant group; p = 0.089) nor the incidence of survival without BPD through 28 days (17% vs 26%, respectively; p = 0.070) was significantly different in the two groups. No significant differences in the incidence of safety-related outcomes or in adverse effects such as apnea or pulmonary hemorrhage were noted. These findings indicate that rescue therapy with synthetic surfactant results in physiologic improvements in very tiny premature infants, but improvements in overall mortality or other complications of respiratory distress syndrome were not documented in the sample evaluated.
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Affiliation(s)
- J Smyth
- British Columbia's Children's Hospital, Vancouver, Canada
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325
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326
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Furman L, Hack M, Watts C, Borawski-Clark E, Baley J, Amini S, Hook B. Twenty-month outcome in ventilator-dependent, very low birth weight infants born during the early years of dexamethasone therapy. J Pediatr 1995; 126:434-40. [PMID: 7869207 DOI: 10.1016/s0022-3476(95)70464-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
We sought to examine the effect of the introduction of dexamethasone therapy on health, growth, and neurodevelopmental outcome in very low birth weight (VLBW) infants at 20 months of age. We compared outcomes in all 86 VLBW infants (mean birth weight 871 gm, mean gestational age 26.4 weeks) who were ventilator dependent on day 21 of life during the 2 years preceding October 1988 (period 1), when dexamethasone therapy became accepted clinical practice in our unit, with outcomes in all 124 infants (mean birth weight 891 gm, mean gestational age 26.9 weeks) with similar ventilator status during the subsequent 2 years (period 2). In addition, we compared outcomes in infants who received dexamethasone during period 2 with those in a concurrent cohort of less ill infants who were not given dexamethasone. There were no significant differences between periods 1 and 2 in mortality rates after 21 days (17% vs 21%), need for home oxygen (23% vs 25%), oxygen dependence at 20 months of corrected age (11% vs 10%), rate of neurosensory impairment (24% vs 25%), and mean Bayley Mental scores (81.5 vs 77.2) or Psychomotor Development Index (81.6 vs 71.1). Infants who received dexamethasone during period 2 had significantly more severe lung disease and poorer respiratory, growth, and developmental outcomes. We conclude that VLBW infants with ventilator-dependent chronic lung disease have very poor outcomes, even when treated with dexamethasone. More information is needed from prospective, randomized trials before dexamethasone can be accepted as routine therapy for chronic lung disease.
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Affiliation(s)
- L Furman
- Department of Pediatrics, Case Western Reserve University, Cleveland, Ohio
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327
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Hack M, Wright LL, Shankaran S, Tyson JE, Horbar JD, Bauer CR, Younes N. Very-low-birth-weight outcomes of the National Institute of Child Health and Human Development Neonatal Network, November 1989 to October 1990. Am J Obstet Gynecol 1995; 172:457-64. [PMID: 7856670 DOI: 10.1016/0002-9378(95)90557-x] [Citation(s) in RCA: 166] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
OBJECTIVE Our purpose was to describe the neonatal outcomes of 1804 very-low-birth-weight (< or = 1500 gm) infants delivered between November 1989 and October 1990 in the participating centers of the National Institute of Child Health and Human Development Neonatal Research Network. STUDY DESIGN In an observational study sociodemographic, pregnancy, and delivery data were collected soon after birth, and neonatal and outcome data at discharge, at 120 days, or at death. RESULTS Maternal and birth weight characteristics included 64% black, 29% white; 71% single mothers; 18% no prenatal care; 17% antenatal steroids; and 12% multiple gestations. Birth weight distributions included 18% weighing 501 to 750 gm, 23% 751 to 1000 gm, 28% 1001 to 1250 gm, and 31% 1251 to 1500 gm. Survival was 39% at < 751 gm birth weight, 77% at 751 to 1000 gm, 90% at 1001 to 1250 gm, and 93% at 1251 to 1500 gm. Survival was 15% to 18% at < or = 23 weeks' gestation, 54% at 24 weeks, 59% at 25 weeks, and 71% at 26 weeks. Surfactant was administered to 45% of the 56% of infants with respiratory distress syndrome. Morbidity, including intraventricular hemorrhage (40%), septicemia (24%), symptomatic patent ductus arteriosus (22%), and necrotizing entercolitis (8%), increased with decreasing birth weight. Oxygen was administered for > or = 28 days to 82% of < 751 gm infants, 49% of 751 to 1000 gm infants, and 10% of > 1001 gm infants. Steroids were administered to 28% of infants who required oxygen for > or = 28 days. Mean hospital stay was 62 days for survivors and 18 days for infants who died. There were large intercenter variations in mortality and morbidity. CONCLUSION Mortality and morbidity in very-low-birth-weight infants improved in 1989 to 1990 without an increase in morbidity or length of hospital stay. The threshold of the improved survival was > or = 24 weeks and 601 to 700 gm. Although such data are reassuring, the rate of major morbidity in < 1001 gm birth weight infants continues to be high.
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Affiliation(s)
- M Hack
- Case Western Reserve University, Cleveland, Ohio
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328
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Speer CP, Gefeller O, Groneck P, Laufkötter E, Roll C, Hanssler L, Harms K, Herting E, Boenisch H, Windeler J. Randomised clinical trial of two treatment regimens of natural surfactant preparations in neonatal respiratory distress syndrome. Arch Dis Child Fetal Neonatal Ed 1995; 72:F8-13. [PMID: 7743295 PMCID: PMC2528411 DOI: 10.1136/fn.72.1.f8] [Citation(s) in RCA: 99] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
AIMS To compare treatment regimens of two widely used natural surfactant preparations Curosurf and Survanta in respiratory distress syndrome (RDS). METHODS The effects of the two treatment regimens on gas exchange, ventilatory requirements, and 28 day outcome in infants with RDS were compared. Seventy five preterm infants (birth weight 700-1500 g) with RDS requiring artificial ventilation with an FIO2 of > or = 0.4, were randomly selected at 1-24 hours of age. One group received an initial dose of Curosurf (200 mg/kg); the other group Survanta (100 mg/kg). Patients who remained dependent on artificial ventilation with an FIO2 of > or = 0.3 received up to two additional doses of Curosurf (each of 100 mg/kg) after 12 and 24 hours or up to three additional doses of Survanta (each of 100 mg/kg) between six and 48 hours after the initial dose. RESULTS There was a rapid improvement in oxygenation and ventilatory requirements were reduced in both groups. However, infants treated with Curosurf had a higher arterial:alveolar oxygen tension ratio and required a lower peak inspiratory pressure and mean airway pressure at several time points within 24 hours of randomisation (p < 0.05-0.001). The incidences of pneumothorax in the Curosurf and Survanta groups were 6% and 12.5%, respectively; the corresponding figures for grades 3-4 intracerebral haemorrhage were 3% and 12.5%, respectively. Mortality was 3% in the Curosurf group and 12.5% in the Survanta group. However, these differences did not reach significance. CONCLUSION The Curosurf treatment regimen resulted in a more rapid improvement in oxygenation than Survanta and reduced ventilatory requirements up to 24 hours after start of treatment. This was associated with a trend towards reduced incidence of serious pulmonary and non-pulmonary complications.
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Affiliation(s)
- C P Speer
- Department of Paediatrics, University of Göttingen, Germany
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329
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Mauskopf JA, Backhouse ME, Jones D, Wold DE, Mammel MC, Mullett M, Guthrie R, Long WA. Synthetic surfactant for rescue treatment of respiratory distress syndrome in premature infants weighing from 700 to 1350 grams: impact on hospital resource use and charges. J Pediatr 1995; 126:94-101. [PMID: 7815233 DOI: 10.1016/s0022-3476(95)70509-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
To determine the impact of the use of synthetic surfactant on hospital resource use and charges, we analyzed the economic data from a multicenter, randomized, placebo-controlled clinical trial of synthetic surfactant in infants with neonatal respiratory distress syndrome and birth weights between 700 and 1350 gm. Two 5 ml/kg doses of a synthetic surfactant (Exosurf Neonatal) or air placebo were administered to 419 infants who were receiving mechanical ventilation and had an arterial/alveolar oxygen tension ratio < 0.22. In addition to the clinical endpoints for safety and efficacy, data were collected on length of hospital stay, days in the neonatal intensive care unit, days of mechanical ventilation, days of oxygen supplementation, and hospital charges until the infant reached 1 year adjusted age. Growth and development of infants who received synthetic surfactant therapy in the study and survived to 1 year adjusted age were equivalent to those of the survivors in the air placebo group. For 1-year survivors, synthetic surfactant reduced the average length of stay at the different levels of care needed during the hospitalization such as neonatal intensive care unit days, days of mechanical ventilation, and days of oxygen supplementation. For nonsurvivors, synthetic surfactant increased the average length of stay, especially at more intense levels of care. Total hospital charges for the initial hospitalization and through 1 year adjusted age for a hypothetic cohort of 100 infants treated with synthetic surfactant were, on average, the same as those for a comparable cohort of infants in the air placebo group. These results indicate that rescue therapy with synthetic surfactant in infants with respiratory distress syndrome and birth weights from 700 to 1350 gm can result in significantly improved survival without significant increases in hospital charges.
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Affiliation(s)
- J A Mauskopf
- Burroughs Wellcome Co., Wellcome Research Labs, Research Triangle Park, North Carolina
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330
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Abstract
Considerable progress has been made in the development of defined mixtures of proteins or peptides with phospholipids which mimic the activity of natural pulmonary surfactants. Several of these biomimetic surfactants are active in animal models and clinical syndromes of surfactant deficiency. This review summarizes the structure and composition of natural surfactants and the development of defined mixtures of peptides and lipids that may be useful in the treatment of respiratory distress.
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Affiliation(s)
- L R McLean
- Marion Merrell Dow Research Institute, Cincinnati, Ohio
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331
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Billman D, Nicks J, Schumacher R. Exosurf rescue surfactant improves high ventilation-perfusion mismatch in respiratory distress syndrome. Pediatr Pulmonol 1994; 18:279-83. [PMID: 7898965 DOI: 10.1002/ppul.1950180503] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
OBJECTIVE To assess ventilation/perfusion (VA/Q) mismatch of the high type, following rescue surfactant therapy for respiratory distress syndrome. HYPOTHESIS Surfactant therapy reduces such mismatch. DESIGN Randomized, double-blind, placebo-controlled study, assessing VA/Q with the arterial-alveolar difference of CO2 tension (P(a-A)CO2). This difference was determined with capnometry and arterial blood gases, using the equation: P(a-A)CO2 equals arterial CO2 minus alveolar CO2 partial pressure. SETTING A level III nursery. PATIENTS Ten intubated infants with respiratory distress syndrome. INTERVENTION Infants were randomized to each receive two doses of surfactant or two doses of air placebo. RESULTS P(a-A)CO2 improved after surfactant and worsened after placebo (P = 0.0021), comparing slopes of 12-hr regression lines. A similar pattern occurred with oxygenation. These changes in P(a-A)CO2 and in oxygenation were minimally correlated within the surfactant group. CONCLUSION Exosurf rescue surfactant reduced VA/Q mismatch of the high type, over several hours.
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Affiliation(s)
- D Billman
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee
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332
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Herting E, Gefeller O, Speer CP, Harms K, Halliday HL, Curstedt T, Robertson B. Intracerebral haemorrhages in surfactant treated neonates with severe respiratory distress syndrome: age at diagnosis, severity and risk factors. Eur J Pediatr 1994; 153:842-9. [PMID: 7843201 DOI: 10.1007/bf01972895] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
UNLABELLED Within a randomized European multicentre trial the time of onset, severity and progression of intracerebral haemorrhages (ICH) were investigated prospectively by serial cranial ultrasonography in 343 ventilated infants with severe respiratory distress syndrome (RDS) following instillation of single or multiple doses of a natural porcine surfactant (Curosurf). In 148/343 infants (43%) ICH was diagnosed (grade I or II: 22%, grade III or IV: 21%). In 26 cases (8%) ICH was present on the ultrasound scan prior to surfactant instillation at a median age of 6 h. Incidence and severity of ICH was similar after single- or multiple-dose surfactant treatment. Using a logistic regression model the following risk factors predictive of ICH were defined: low birth weight, allocation to certain hospitals, vaginal delivery, Apgar score < or = 6, rectal temperature on admission < or = 36 degrees C, primary anaemia, acidosis prior to treatment, RDS grade IV in pre-treatment chest films and poor response to surfactant treatment. CONCLUSION Our study provides supportive evidence that multiple doses of Curosurf do not increase the risk for ICH as compared to single-dose administration.
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Affiliation(s)
- E Herting
- Research Unit for Experimental Perinatal Pathology, Karolinska Hospital, Stockholm, Sweden
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333
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Corcoran JD, Berggren P, Sun B, Halliday HL, Robertson B, Curstedt T. Comparison of surface properties and physiological effects of a synthetic and a natural surfactant in preterm rabbits. Arch Dis Child Fetal Neonatal Ed 1994; 71:F165-9. [PMID: 7820710 PMCID: PMC1061118 DOI: 10.1136/fn.71.3.f165] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
AIMS To compare the physical and physiological properties of a synthetic surfactant (Exosurf, Wellcome Foundation) and a natural surfactant (Curosurf, Chiesi Farmaceutici). METHODS Surface properties of the surfactant suspensions (10 mg phospholipid/ml) were evaluated using the pulsating bubble surfactometer. Lung-thorax compliance was determined in 47 immature newborn rabbits with a gestational age of 27 days, treated with recommended clinical doses of either surfactant (Exosurf 67.5 mg/kg; Curosurf 200 mg/kg). The lungs were examined histologically. RESULTS The mean (SD) contractile forces of the surface at maximum and minimum bubble size were significantly lower for Curosurf than for Exosurf: 31 (2) and 0 (0) mN/m v 53 (5) and 29 (4) mN/m, respectively. Mean (SD) lung-thorax compliance after one hour of ventilation was significantly higher in rabbits treated with Curosurf compared with animals receiving Exosurf or those serving as controls: 0.60 (0.15) ml/cm H2O.kg v 0.44 (0.03) and 0.34 (0.18) ml/cm H2O.kg, respectively. Both surfactants increased alveolar volume density compared with results for control animals, but only Curosurf significantly reduced the incidence of moderate or severe bronchiolar epithelial disruption. CONCLUSIONS The natural surfactant, Curosurf, reduced the contractile force at an air-liquid interface to a greater extent than the synthetic surfactant, Exosurf, and led to a greater improvement in compliance and less airway epithelial damage when given in clinical treatment doses to immature rabbits.
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Affiliation(s)
- J D Corcoran
- Department of Child Health, Queen's University, Belfast
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334
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Verder H, Robertson B, Greisen G, Ebbesen F, Albertsen P, Lundstrøm K, Jacobsen T. Surfactant therapy and nasal continuous positive airway pressure for newborns with respiratory distress syndrome. Danish-Swedish Multicenter Study Group. N Engl J Med 1994; 331:1051-5. [PMID: 8090164 DOI: 10.1056/nejm199410203311603] [Citation(s) in RCA: 253] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
BACKGROUND In southern Scandinavia most babies with respiratory distress syndrome are initially treated with nasal continuous positive airway pressure. We performed a multicenter trial to investigate whether the addition of a single dose of porcine surfactant administered during a short intubation before the occurrence of serious deterioration could reduce the subsequent need for mechanical ventilation. METHODS We randomly assigned 35 infants with moderate-to-severe respiratory distress syndrome to surfactant therapy (Curosurf, 200 mg per kilogram of body weight) plus nasal continuous positive airway pressure and 33 infants to nasal continuous positive airway pressure alone. The study was not blinded. The indications for mechanical ventilation were a ratio of arterial to alveolar oxygen tension of less than 0.15, severe apneic attacks, or both. RESULTS Six hours after randomization, when the median age of the babies was 18 hours, the mean ratio of arterial to alveolar oxygen tension was 0.37 in the surfactant-treated babies, as compared with 0.25 in the controls (P < 0.001). The need for subsequent mechanical ventilation was reduced with surfactant therapy (to 43 percent of the surfactant-treated babies as compared with 85 percent of the controls; P = 0.003). When 17 infants with ratios of arterial-to-alveolar oxygen tension of less than 0.15 at randomization were excluded, the need for mechanical ventilation was still significantly reduced in the surfactant-treated group (to 33 percent [9 of 27 babies], as compared with 83 percent [20 of 24 babies] in the control group; (P < 0.001). After 28 days, two of the surfactant-treated babies had died, as compared with five of the control babies. CONCLUSIONS In babies with moderate-to-severe respiratory distress syndrome treated with nasal continuous positive airway pressure, a single dose of surfactant reduced the need for subsequent mechanical ventilation.
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Affiliation(s)
- H Verder
- Department of Pediatrics, Holbaek Central Hospital, Denmark
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335
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336
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Wiseman LR, Bryson HM. Porcine-derived lung surfactant. A review of the therapeutic efficacy and clinical tolerability of a natural surfactant preparation (Curosurf) in neonatal respiratory distress syndrome. Drugs 1994; 48:386-403. [PMID: 7527760 DOI: 10.2165/00003495-199448030-00006] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Porcine-derived lung surfactant (PLS; Curosurf) has shown efficacy in neonatal respiratory distress syndrome. PLS consists of phospholipids, mainly dipalmitoylphosphatidylcholine, the primary surface-active agent of natural lung surfactant, and pulmonary surfactant-associated proteins which facilitate spreading and adsorption of the surface-active agent at the air-alveolar interface. Intratracheal administration of a single dose of PLS 200 mg/kg significantly improves the survival rate and reduces the incidence of bronchopulmonary dysplasia at 28 days in premature infants (birthweight 700 to 2000g) with severe respiratory distress syndrome (fraction of inspired oxygen > or = 0.60). PLS also reduces the incidence of air leak events such as pulmonary interstitial emphysema and pneumothorax. The response rate may be further improved by administration of additional 100 mg/kg doses at 12-hour intervals to infants showing a poor response or relapse after a single dose. PLS prophylaxis reduces the incidence and severity of respiratory distress syndrome in premature infants at high risk of developing the disease; however, it remains unclear whether the eventual clinical outcome is similar or superior to that observed in infants who receive rescue treatment. PLS is well tolerated and does not appear to increase the incidence of complications of prematurity or respiratory distress syndrome, including patent ductus arteriosus and intraventricular haemorrhage. Although its effect on long term development require further investigation, early indications are that PLS is not associated with any long term adverse sequelae. Comparative trials are clearly warranted to determine the efficacy and tolerability of PLS relative to that of other available surfactant preparations, particularly to explore preliminary indications that a more rapid effect of natural surfactants such as PLS (compared with synthetic products) may correlate with improved clinical outcomes, and that PLS may result in fewer complications than synthetic preparations. Thus, available data show PLS to be a very effective agent for the treatment and prophylaxis of neonatal respiratory distress syndrome, and that it may have some advantages over synthetic preparations.
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Affiliation(s)
- L R Wiseman
- Adis International Limited, Auckland, New Zealand
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337
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Pinar H, Makarova N, Rubin LP, Singer DB. Pathology of the lung in surfactant-treated neonates. PEDIATRIC PATHOLOGY 1994; 14:627-36. [PMID: 7971582 DOI: 10.3109/15513819409023337] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Respiratory distress syndrome (RDS) is associated with prematurity-related deficiency of surfactant. Surfactant replacement therapy has been used in premature infants to prevent RDS or reduce its severity. In this study we describe the pathology of the lungs after surfactant replacement therapy. All the neonatal autopsies during the years 1989 and 1990 (n = 235) were examined. Infants > or = 31 weeks gestation, with congenital anomalies or who lived more than 2 weeks were excluded from the study. Infants who had received intratracheal Survanta, a modified surfactant extracted from cow lung (n = 14), were compared with infants who did not receive exogenous surfactant (n = 20). The two groups were statistically comparable in terms of weight, gestational and postnatal age, gender, and clinical management. H&E-stained lung sections were examined independently by two pathologists without knowledge of surfactant treatment status; any discrepancies in histological evaluation were resolved by joint review. Nine histological features were evaluated including hyaline membranes, necrosis of the epithelium, hemorrhage, edema, inflammation, metaplasia, arteriolar muscular hyperplasia, interstitial fibrosis, and pulmonary interstitial emphysema (PIE). Histological changes were graded from 0 to 3+. When it was present, cerebral periventricular-intraventricular hemorrhage (PVH-IVH) was graded 1-4. The presence or absence of sepsis and necrotizing enterocolitis (NEC) were also determined. Comparisons between patient groups were performed using the Mann-Whitney U, Student's t and chi 2 tests. The severity of hyaline membrane disease, PIE, and epithelial necrosis was less severe in the surfactant-treated group than in the untreated group. There were no differences between the two groups in the degree of pulmonary hemorrhage or in the incidence of PVH-IVH, sepsis, or NEC.
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Affiliation(s)
- H Pinar
- Department of Pathology and Laboratory Medicine, Women and Infants' Hospital of Rhode Island, Providence 02905
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338
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Knight DB, Liggins GC, Wealthall SR. A randomized, controlled trial of antepartum thyrotropin-releasing hormone and betamethasone in the prevention of respiratory disease in preterm infants. Am J Obstet Gynecol 1994; 171:11-6. [PMID: 8030684 DOI: 10.1016/s0002-9378(94)70070-2] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
OBJECTIVE The objective was to investigate whether the addition of thyrotropin-releasing hormone to antepartum betamethasone further reduces the incidence of respiratory disease in preterm infants. STUDY DESIGN A randomized, placebo-controlled, double-blind trial of antepartum thyrotropin-releasing hormone (400 micrograms given intravenously four times) and betamethasone (5 mg given intramuscularly four times) was conducted in 378 mothers likely to be delivered between 24 and 32.6 weeks' gestation. Statistical analysis was by relative risk, chi 2, t tests, and multiple logistic regression analysis. RESULTS Four hundred five live-born infants were delivered. In infants without lethal abnormalities delivered between 24 hours and 10 days from entry (n = 175) the incidence of respiratory distress syndrome was reduced from 52% to 31% (relative risk 0.61, 95% confidence interval 0.41 to 0.89) and that of severe respiratory distress syndrome from 42% to 20% (relative risk 0.48, 95% confidence interval 0.29 to 0.78) in the placebo and thyrotropin-releasing hormone groups, respectively. The number of deaths fell from 14 to one (relative risk 0.08, 95% confidence interval 0.01 to 0.63). The incidence of chronic lung disease was not significantly different, but that of an adverse outcome (chronic lung disease or death by 36 weeks' gestation) fell from 29% in the placebo group to 16% with thyrotropin-releasing hormone (relative risk 0.55, 95% confidence interval 0.31 to 0.99). CONCLUSION The addition of thyrotropin-releasing hormone to antepartum glucocorticoid treatment reduces the incidence of respiratory distress syndrome and improves survival in preterm infants.
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Affiliation(s)
- D B Knight
- Department of Paediatrics, National Women's Hospital, Auckland, New Zealand
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339
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Scheffers EC, IJsselstijn H, Tenbrinck R, Lachmann B, de Jongste JC, Molenaar JC, Tibboel D. Evaluation of lung function changes before and after surfactant application during artificial ventilation in newborn rats with congenital diaphragmatic hernia. J Pediatr Surg 1994; 29:820-4. [PMID: 8078029 DOI: 10.1016/0022-3468(94)90379-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Patients with congenital diaphragmatic hernia (CDH) have unilateral or bilateral hypoplasia of the lungs including delayed maturation of the terminal air sacs. Because these lungs are highly susceptible to barotrauma and oxygen toxicity, even in full-term newborns, continued research into optimal ventilatory regimen is essential to improve survival rate and to prevent ongoing lung damage. Against this background, the effect of exogenous surfactant application is evaluated. In newborn rats, CDH was induced after a single dose of 2,4 dichloro-4'-nitrophenyl (Nitrofen) (400 mg/kg) on day 10 of gestation. The newborn rats were intubated immediately after hysterotomy, transferred to a heated multichambered body plethysmograph, and artificially ventilated. Inspiratory peak pressures were initially set at 17 cm H2O, with positive end-expiratory pressure at 0 cm H2O and FIO2 at 1.0. The pressure was raised in steps of 5 cm H2O, from 5 to 30 cm H2O, to obtain pressure-volume diagrams at 0, 1, and 6 hours of artificial ventilation. These measurements were obtained in controls and in CDH rats with and without endotracheal installation of bovine surfactant (n = 4 to 10 in each group). Significant differences in lung volume between CDH and control rats were observed at all time-points. Surfactant application had a positive effect on lung volume, especially in control rats at t = 1 hour. No significant differences were observed between the CDH groups at t = 1 or t = 6 hours. In this animal model, the effect of artificial ventilation as well as the beneficial short-term effect of exogenous surfactant application have been evaluated. A continued positive effect on lung volume in CDH lungs could not be determined. Routine administration of exogenous surfactant in human CDH patients is not supported by these experimental results.
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Affiliation(s)
- E C Scheffers
- Department of Paediatric Surgery, Sophia Children's Hospital, Rotterdam, The Netherlands
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340
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Zimmerman JJ, Farrell PM. Advances and issues in bronchopulmonary dysplasia. CURRENT PROBLEMS IN PEDIATRICS 1994; 24:159-70. [PMID: 7915224 DOI: 10.1016/0045-9380(94)90033-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- J J Zimmerman
- Department of Pediatrics, University of Wisconsin, Madison
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341
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Pappin A, Shenker N, Hack M, Redline RW. Extensive intraalveolar pulmonary hemorrhage in infants dying after surfactant therapy. J Pediatr 1994; 124:621-6. [PMID: 8151480 DOI: 10.1016/s0022-3476(05)83145-2] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
To assess the possible relationship between exogenous surfactant therapy and pulmonary hemorrhage in premature infants, we compared autopsy findings in 15 infants treated with exogenous surfactant and in 29 who died before the introduction of surfactant therapy. Infants who met the following criteria were included: birth weight 501 to 1500 gm, survival 4 hours to 7 days, and no congenital anomalies. Average birth weight, gestational age, and age at death were equivalent for the two groups. High rates of pulmonary hemorrhage were present in both groups (treated 80% vs untreated 83%). The untreated group had higher incidences of interstitial hemorrhage and lung hematomas and significantly more large interstitial hemorrhages: 31% untreated versus 0% treated (p < 0.05). The overall rate of intraalveolar hemorrhage was similar in the two groups, but surfactant-treated infants were more likely to have extensive intraalveolar hemorrhage: 53% versus 14% (p < 0.05). Most surfactant-treated infants who survived more than 24 hours had extensive intraalveolar hemorrhage (8/9). Patients who had extensive intraalveolar hemorrhage, with or without prior surfactant therapy, frequently had clinically significant pulmonary hemorrhage (7/12). These findings indicate that infants who die after surfactant therapy have higher rates of a specific type of pulmonary hemorrhage--extensive intraalveolar hemorrhage.
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Affiliation(s)
- A Pappin
- Department of Pathology, Case Western Reserve University School of Medicine, Cleveland, Ohio
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342
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343
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Inder TE, Graham P, Sanderson K, Taylor BJ. Lipid peroxidation as a measure of oxygen free radical damage in the very low birthweight infant. Arch Dis Child Fetal Neonatal Ed 1994; 70:F107-11. [PMID: 8154902 PMCID: PMC1061010 DOI: 10.1136/fn.70.2.f107] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
(ABSTRACTOxygen free radical mediated tissue injury is implicated as a major factor in the pathogenesis of the long term complications seen in the premature infant, and direct evidence of their role in the development of these long term problems is lacking. A prospective observational study of 78% of very low birthweight infants admitted to a level III neonatal intensive care unit in 1992 was undertaken to determine the relationship between lipid peroxidation products, antioxidant activity, and outcome. Lipid peroxidation (malondialdehyde-thiobarbituric acid, MDA-TBA) and antioxidant activity (vitamin E and glutathione peroxidase activity) were measured in 22 very low birthweight infants in the cord blood and the infant's blood at 24 hours, 48 hours, and 1 week of age and correlated with outcome measures. The normal range for these measures was established in the cord blood samples of 48 consecutive healthy full term infants. The concentration of MDA-TBA at 1 week correlated with the number of days of oxygen treatment and number of days of positive pressure ventilatory support. Controlling for gestational age and antenatal complications simultaneously the MDA-TBA concentration remained significantly associated with the number of days of oxygen treatment and the number of days of positive pressure ventilatory support. Glutathione peroxidase was low in the premature and full term infants consistent with the low concentrations of selenium known to be present in southern New Zealand. There was evidence of a quadratic relationship between vitamin E at 1 week and the total number of days of supplementary oxygen requirement, with both high and low values associated with increased oxygen requirement. This association, however, did not remain after controlling for gestational age and antenatal complications. These results support the role of oxygen free radicals in mediating tissue damage associated with the development of chronic lung disease in the premature infant.
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Affiliation(s)
- T E Inder
- Department of Paediatrics and Child Health, Dunedin Hospital, Dunedin, New Zealand
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344
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345
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Zarowitz BJ, Gonzalez E, Dasta J. Recent advances in critical care. Ann Pharmacother 1994; 28:245-7. [PMID: 8173145 DOI: 10.1177/106002809402800217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Affiliation(s)
- B J Zarowitz
- Department of Pharmacy Services, Henry Ford Hospital, Detroit, MI 48202
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346
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Wood RE, Knowles MR. Recent advances in aerosol therapy. JOURNAL OF AEROSOL MEDICINE : THE OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY FOR AEROSOLS IN MEDICINE 1993; 7:1-11. [PMID: 10147056 DOI: 10.1089/jam.1994.7.1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- R E Wood
- Department of Pediatrics, University of North Carolina at Chapel Hill 27514
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347
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Merritt TA, Amirkhanian JD, Helbock H, Halliwell B, Cross CE. Reduction of the surface-tension-lowering ability of surfactant after exposure to hypochlorous acid. Biochem J 1993; 295 ( Pt 1):19-22. [PMID: 8216215 PMCID: PMC1134814 DOI: 10.1042/bj2950019] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The reactive species hypochlorous acid (HOCl/OCl-) is a major product of the respiratory burst in activated neutrophils. We studied the effects of HOCl/OCl- on human surfactant and upon surfactants Survanta, KL4 and Exosurf, utilizing a pulsating surfactometer for measuring surface tension. HOCl/OCl- induced a marked dose-dependent decrease in the surface-tension-lowering activity of human surfactant. The surfactant containing surfactant proteins B and C (Survanta) was less sensitive; however, synthetic surfactants with or without peptides were not affected by HOCl/OCl- (KL4, Exosurf). Ascorbic acid and GSH protected human surfactant against inactivation by HOCl/OC1-. We suggest that HOCl/OCl- produced by activated phagocytes in the alveolar compartment of the lung could damage endogenous surfactant and affect the function of exogenously administered natural or other surfactants, especially if ascorbic acid and GSH levels in the lung lining fluids are subnormal, as is known to be the case in some inflammatory lung diseases.
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Affiliation(s)
- T A Merritt
- Division of Neonatology, University of California, Davis, Medical Center, Sacramento 95817
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