CONTINUOUS POSITIVE AIRWAY PRESSURE WITH A FACE CHAMBER IN EARLY TREATMENT OF IDIOPATHIC RESPIRATORY DISTRESS SYNDROME

CPAP treatment started early with a new face chamber was found to be convenient and, without risks. Treatment of IRDS applied early with the presented technique appears to radically improve the prognosis.     

ERYTHROPOIETIN LEVELS IN CORD BLOOD OF CONTROL INFANTS AND INFANTS WITH RESPIRATORY DISTRESS SYNDROME

Erythropoietin levels (ESF) were measured in premature infants with and without the respiratory distress syndrome in an effort to define the role of intrauterine hypoxia in the genesis of the disease. No difference in levels could be detected between infants with and without the: respiratory distress syndrome. This suggests that either intrauterine hypoxia plays no role in the genesis of the respiratory distress syndrome or that the hypoxia is (1) of short duration, (2) of relatively long duration, or (3) remote with respect to the time of birth. The higher levels found in full-term infants suggested that hypoxia before birth is a more common feature of the term delivery than the premature delivery.     

LONG TERM PROGNOSIS OF INFANTS WITH SEVERE IDIOPATHIC RESPIRATORY DISTRESS SYNDROME

ABSTRACT. 76 out of 77 children surviving IRDS with the aid of intermittent positive pressure ventilation have been folio ed-up by the age 2.6–7.6 years together with 68 matched controls. Moderate or severe neurological, developmental or mental abnormalities were present in 17% of all IRDS survivors. Statistical comparison of the matched pairs of IRDS survivors and controls revealed no significant differences in the prevalence of abnormalities. In the IRDS survivors the occurence of cerebral palsy related to prematurity while the development of psycho-motor and mental retardation related to low birth weight and low milk ìntake durìng the first week suggesting that both prenatal and postnatal growth retardation may have been of importance. Statistical analysis of a number of preventilatory and ventilatory parameters did not show significant differences between these groups of IRDS survivors and the remainder. Ventilator treatment is recommended as a promising adjunct to the therapy of severe IRDS in centers where the necessary experience and equipment is at hand.     

EARLY CLOSURE OF PATENT DUCTUS ARTERIOSUS WITH INDOMETHACIN IN PRETERM INFANTS WITH IDIOPATHIC RESPIRATORY DISTRESS SYNDROME

ABSTRACT. Thirty-seven preterm infants with idiopathic respiratory distress syndrome were prospectively studied for the effect of the early closure of patent ductus arteriosus with indomethacin on the course of idiopathic respiratory distress syndrome. Serial retrograde aortograms were performed in all infants in order to visualize the ductus arteriosus, apart from three patients, who died early and were evaluated aortographically only once. The ductus was initially open in 27 infants and closed in 10 infants. The infants with open ductus arteriosus were randomly divided into two groups. The first group consisted of 13 infants, in whom the ductus was closed with indomethacin at a median age of 18 hours. The other 14 infants served as controls. Total time on assisted ventilation and duration of exposure to additional oxygen were significantly shorter in medicated infants than in controls. Oxygenation of infants with an initially closed ductus was better from birth and duration of their ventilatory assistance and oxygen exposure were shorter than in infants with initial ductal shunting. The data suggest that the early closure of the patent ductus arteriosus with indomethacin in distressed preterm infants has a favourable effect on the course of idiopathic respiratory distress syndrome.     

RENAL FUNCTION IN IDIOPATHIC RESPIRATORY DISTRESS SYNDROME

ABSTRACT. Renal function was studied in 11 pre-term infants with idiopathic respiratory distress syndrome (IRDS) grade 1 according to Prod'hom's criteria. As a reference 16 healthy pre-term infants were studied. The groups did not differ with regard to mean gestational age (GA) and mean postnatal age (PNA). The studies were preformed twice, first at a PNA of 33–37 hours and then at 132–148 hours. GFR and C_PAH were determined with the single injection technique and the ability to excrete Na was determined following an oral Na⁺ load. GFR was higher in IRDS infants at the first investigation and slightly lower in IRDS infants at the second investigation. The GFR correlated to the lowest recorded P_ao2 r=0.45) in IRDS infants. C_PAH was similar in IRDS and controls at the first, and lower in IRDS infants at the second investigation. The urinary Na⁺ excretion was significantly higher in IRDS infants. Treatment with digitalis was in part responsible for the high urinary Na⁺ excretion. The IRDS infants had a higher Na⁺ and glucose intake than the control infants. It is suggested that this higher intake is in part responsible for the relatively high GFR and urinary Na⁺ excretion in the IRDS infants.     

LONG-TERM PROGNOSIS OF INFANTS WITH IDIOPATHIC RESPIRATORY DISTRESS SYNDROME Follow-up Studies in Infants Surviving after the Introduction of Continuous Positive Airway Pressure

Abstract. Fifty-one children surviving IRDS with CPAP alone or CPAP and IPPV were studied at the age of 2.5 to 4.0 years. One child had developed tetraplegia and mental retardation and 6 children were speech-retarded. Correlation with perinatal events showed that this group of children had a significantly lower gestational age and birth weight, a lower Apgar score and a higher P_ço2 prior to ventilatory treatment than the remainder. Re-examination by age 4.0 to 5.0 years showed persistent handicaps in only four of the seven children.     

THE FOAM STABILITY TEST ON GASTRIC ASPIRATE IN THE PREDICTION OF RESPIRATORY DISTRESS SYNDROME

Abstract. To evaluate the usefulness of the foam stability test (FST) on gastric aspirate for predicting respiratory distress syndrome (RDS) in premature infants, samples were collected at delivery or within 30 min from 194 infants ≤36 weeks gestation. Of 123 samples adequate for complete testing, 44 were positive at 1:2 dilution, 43 were positive only at dilutions <1:2 and 36 were negative at all dilutions. RDS was found in 2%, 21% and 25% of each group respectively. The FST on gastric aspirate at birth gives useful information only if positive at 1:2 when a very low incidence of RDS may be expected. However, a large proportion of infants with FST negative at 1:1 do not develop RDS, and hence the test is of limited value in screening for those with highest risk.     

肺表面活性物质预防早产儿RDS的临床观察

目的 探讨肺表面活性物质(PS)预防用药对预防早产儿呼吸窘迫综合征(RDS)及改善早产儿预后的可行性。方法 我院胎龄≤32W的早产儿12例,于生后预防应用PS(预防组);同期确诊为RDS 17例应用呼吸机和PS(治疗组),比例两RDS发生率、呼吸机参数、并发症及预后。结果 预防组RDS发生3例,发生率为25％,低于我院同期收治的≤32W早产儿RDS发生率(43％);预防组RDS 3例均为Ⅱ期,治疗组Ⅲ期、Ⅳ为52.9％(9/17)。预防组上呼吸机所需压力明显低于治疗组,(P<0.05);肺炎、感染、颅内出血等合并症有下降趋势;未有气漏及BPD的发生。结论 PS预防用药可降低早产儿RDS发生率及减轻发病程度,减少呼吸机的应用,减少并发症,改善早产儿预后。     

允许性高碳酸血症通气法治疗新生儿呼吸窘迫综合征

目的 探讨允许性高碳酸血症通气法(PHV)在治疗新生儿呼吸窘迫综合征(NRDS)中的价值。方法 随机选择两组需机械通气治疗的NRDS病人,对照组(n=25)以传统通气方式治疗,PHV组(n=31)降低PIP、PEEP、MAP等通气条件,允许血气中PaCO_2超过正常值,在45～55mmHg之间,比较两组通气条件、通气过程中血气值及并发症、病死率。结果 两组在通气过程中,PaCO_2/FiO_2及PaCO_2无显著性差异(P均>0.05),而pH值、PaCO_2有显著性差异(P<0.05和P<0.01),同时PHV组上机时间显著减少(P<0.05),气漏发生率和病人死亡率均降低(0/12％和12.9％/24％)。结论 PHV法在治疗NRDS中较传统通气方式能降低并发症的发生率及病死率,具有推广价值。     

THE TRANSCAPILLARY ESCAPE RATE OF T-1824 IN NEWBORN INFANTS OF DIABETIC MOTHERS AND NEWBORN INFANTS WITH RESPIRATORY DISTRESS OR BIRTH ASPHYXIA

ABSTRACT. Ingomar, C. Joh. and Klebe, J. G. (Diabetes Center of the Royal Maternity Hospital and the University Department for Newborn Infants, Rigshospitalet, Copenhagen, Denmark). The transcapillary escape rate of T-1824 in newborn infants of diabetic mothers and newborn infants with respiratory distress or birth asphyxia. Acta Paediatr Scand, 63: 565, 1974.—The influence of certain clinical conditions (idiopathic respiratory distress, birth asphyxia and diabetic embryopathy) on the transcapillary escape rate of human albumin, was investigated in 52 newborn infants. The dyestuff T-1824 (Evan's blue) was used for the labelling of plasma albumin in vivo, and its plasma concentration was determined spectrophotometrically using a micro-method. From serial measurements carried out during the first hour following the injection of T-1824, the escape rate (%/hour) was calculated. Among healthy newborn infants the escape rate was found to increase proportional to the magnitude of the placental transfusion. The same applied to infants with respiratory distress and infants of diabetic mothers, the escape rate of whom did not differ from that of healthy infants. By contrast, the escape rate of albumin was, among some cases of birth asphyxia, found to be increased out of proportion to the placental transfusion, which the infants had received. It is discussed whether the increased escape rate found in these cases is caused by an increased capillary permeability or an increased capillary surface area.     

ACTIVATION OF THE KALLIKREIN-KININ SYSTEM IN PREMATURE INFANTS WITH RESPIRATORY DISTRESS SYNDROME (RDS)

ABSTRACT. Plasma prekallikrein levels, kallikrein activity and antikallikrein levels were investigated in nine premature infants with respiratory distress syndrome (RDS) and six premature infants without. Plasma prekallikrein and kallikrein were determined with a chromogenic substrate measuring amidolytic activity. Antikallikrein was measured with a functional assay. In infants with severe RDS, prekallikrein levels were significantly reduced (median 58% of initial values ( p <0.01) about 48 hours after onset of symptoms. In infants with moderate RDS prekallikrein level was reduced less, while in babies without RDS there were no significant changes in prekallikrein levels the first 5-7 days of life. Antikallikrein levels did not change significantly in any babies. The results suggest that the kallikrein-kinin system might be involved in RDS. This could explain several features of this syndrom such as hypotension and edema. Furthermore the findings show that homeostatic functions are altered in this disease, and they suggest that other cascade systems as the coagulation, fibrinolytic and complement system may be involved as well. The findings emphasize that trauma might be a significant pathogenetical factor for development of this syndrome and indicate that RDS is not simply a biochemical disease with lack of surfactant as the only pathogenetic factor.     

FIBRINOGEN TURNOVER IN THE PREMATURE INFANT WITH AND WITHOUT IDIOPATHIC RESPIRATORY DISTRESS SYNDROME

Measurement of the elimination of small quantities of ¹²⁵I-fibrinogen (5–15 μCi) demonstrates shortened half-life and higher catabolic rates in premature infants, and particularly in those infants suffering from IRDS compared with adults. Turnover in the adult is 15%, in the premature 25 % and in the premature with IRDS 33 % per day. Equilibrium between intravascular and extravascular fibrinogen is not achieved before the third day of life. Later, elimination is linear. There is a highly significant difference between ^32rT-fibrinogen catabolism in the adult and the premature infant with and without the IRDS between the third and twelfth day. Measurement of activity over various organs demonstrates that slow efiux of ¹²⁵I-fibrinogen into the extravascular compartment causes a continuous fall in plasma activity during the first 2–3 days. In premature infants with IRDS the activity over the lungs rises during the first day of life. These results allow the conclusion that accelerated fibrinogen synthesis in infants with IRDS compensates for losses into the hyaline membranes and intravascular clots and even allows the physiological rise in plasma fibrinogen level during the first three days to take place.     

PULMONARY MECHANICS IN INFANTS SURVIVING SEVERE NEONATAL RESPIRATORY INSUFFICIENCY

Abstract. Ahlström, H. (Departments of Paediatrics and Clinical Physiology, University Hospital, Lund, Sweden). Pulmonary mechanics in infants surviving severe neonatal respiratory insufficiency. Acta Paediatr Scand, 64:69, 1975.–Pulmonary mechanics was studied in 24 survivors of severe neonatal ventilatory insufficiency, 15 infants had idiopathic respiratory distress syndrome (IRDS), 6 recurrent severe apnoeic spells, and 3 postasphyxia syndrome. Of the infants with IRDS, 5 were treated with intermittent positive pressure ventilation (IPPV), 3 with continuous positive airway pressure (CPAP) via an endotracheal tube and 7 with CPAP applied via a face chamber. The other infants were all treated with IPPV. IPPV-treated infants generally had lower than expected values of dynamic compliance and pulmonary conductance, particularly after prolonged treatment. All infants treated with CPAP via a face chamber had normal mechanics, but a trend towards obstruction of the airways after varying periods of time was observed in most infants, irrespective of diagnosis or treatment. One infant treated with CPAP via an endotracheal tube and given pure oxygen for a long time had gross abnormalities suggesting bronchopulmonary dysplasia. Measurement of pulmonary conductance appears to be a reliable prognostic tool as concerns pulmonary symptoms later in infancy.     

PITUITARY-ADRENAL AND TESTICULAR FUNCTION IN PRETERM INFANTS AFTER PRENATAL DEXAMETHASONE TREATMENT

ABSTRACT. Pituitary-adrenal and testicular function was monitored by plasma ACTH and testosterone (T) measurements in preterm newborns (gestational age below 36 weeks), exposed in utero to dexamethasone treatment for prevention of respiratory distress syndrome. A group of age-matched premature newborns and full-term infants served as controls. The cord-blood ACTH level was high in each group (logarithmic means 65-75 ng/l), but decreased within the first 2 days of life to mean levels between 20-30 ng/l on days 3 to 10 inclusive. Dexamethasone treatment had no effect on the postnatal ACTH concentrations when compared with preterm or full-term controls. Similarly, no differences in plasma ACTH were found between untreated preterm and full-term infants during the first 10 days of life. T levels in mixed cord blood were on average 2-3 nmol/l in the preterm male infants. An increase to a mean level of 10 nmol/l was seen in 1 h and 1d samples. Thereafter, the concentration of T decreased to 2-3 nmol/l on days 3-10 postnatally. No effect of dexamethasone treatment was seen on the postnatal pattern of plasma T. When preterm male and full-term male infants were compared, no difference was seen in the T peak in the first day of life. However, the 1-3, and 60-90 day concentrations of T were 2-fold ( p <0.01–0.05) higher in the preterm group. It is concluded that prenatal dexamethasone treatment of the mother does not influence the postnatal pituitary-adrenal function as monitored by ACTH measurements. Likewise, no effect of this treatment was observed on the postnatal testicular activity of preterm male infants. The immediate postnatal peak in plasma T levels persisted longer in the preterm than in the full-term male infants.     

CONTINUOUS NEGATIVE CHEST-WALL PRESSURE THERAPY FOR ASSISTING VENTILATION IN OLDER CHILDREN WITH PROGRESSIVE RESPIRATORY INSUFFICIENCY1

Abstract. Continuous negative chest-wall pressure (CNP) was used to assist ventilation in 14 children, 6 months to 14 years of age, who had progressive respiratory insufficiency caused by diffuse bilateral alveolar disease. Before the start of CNP therapy, each child had a respiratory rate>50/min, arterial oxygen tension (PaO₂)<70 mmHg (FIO₂≥50%), and arterial carbon dioxide tension (PaCO₂)<45 mmHg. The mean intrapulmonary right-to-left shunt was 28.7±3.8%. Within 6 hours after therapy was started, PaO₂ increased from 55.4±15.9 to 81.6±17.7 mmHg (p<0.005). This improvement was sustained and within 24 hours permitted a decrease in fractional concentration of inspired oxygen (FIO₂) from 51.8±6.2 to 41.0±8.4% (p<0.001) and in respiratory rate from 78.1±23.0 to 56.4±21.3 (p<0.01). There was a concomitant decrease in intrapulmonary right-to-left shunt. Four of the 14 patients developed pneumothorax that was successfully decompressed. Ten patients survived. These observations establish CNP therapy as an effective means of improving arterial oxygenation in spontaneously breathing older children. Of added significance, this mode of therapy eliminates the need for endotracheal intubation and prolonged use of muscle relaxants and sedatives. It also minimizes exposure to high FIO₂, thereby minimizing the hazards of pulmonary oxygen toxicity.     

THE EFFECT OF CHLORPROMAZINE IN SEVERE HYPOXIA IN NEWBORN INFANTS

ABSTRACT. Eighteen newborn infants with severe hypoxia during the course of idiopathic respiratory distress syndrome, pneumonia, persistent fetal circulation or right diaphragmatic hernia were treated with chlorpromazine with the aim of improving arterial oxygenation by a postulated vasodilatory action on the pulmonary circulation. Fourteen of the infants improved their P_SO2 during the treatment. Nine infants died. The systematic arterial blood-pressure and the urinary output were reduced and some infants were somnolent during the initial period of treatment. No other side effects were noted. Further studies of chlorpromazine as a possible pulmonary vasodilator in newborn infants are justified.     

RESPIRATORY INSUFFICIENCY SYNDROME (RIS) IN PRETERM INFANTS WITH GESTATIONAL AGE OF 32 WEEKS AND LESS

ABSTRACT: Carlsson, J. and Svenningsen, N. W. (Department of Paediatrics, University Hospital, Lund, Sweden). Respiratory insufficiency syndrome (RIS) in preterm infants with gestational age of 32 weeks and less. Neonatal management and follow-up study. Acta Paediatr Scand, 64: 813, 1975.–The clinical entity of respiratory insufficiency syndrome (RIS), i.e. irregular breathing leading to recurrent apnea and bradycardia in an otherwise healthy preterm infant, has been studied in respect of symptomathology and management with intensive case including ventilatory support. During a 4-year period 26 of 103 infants with gestational age 32 weeks and mean birth weight 1304 g (range 710 to 1830 g) developed RIS. In most infants the initial apnea occurred after 2 and before 72 hours post delivery but in some infants later. Because of progressive hypoxemia and acidosis IS of the 26 RIS infants required IPPV treatment. The 76 % survival rate of RIS infants seems to justify intensive care with ventilatory support even in the smallest preterm infants with RIS, especially as the follow-up study performed at 15 months to 3 ½ years of age showed neurological sequelae in only 3 of 20 surviving babies, i.e. 15 % sequelae rate.     

EDEMA FORMATION IN THE LUNGS AND ITS RELATIONSHIP TO NEONATAL RESPIRATORY DISTRESS

Bland, R. D. (Cardiovascular Research Institute and Department of Pediatrics, University of California, San Francisco, Ca, USA). Edema formation in the lungs and its relationship to neonatal respiratory distress. Acta Paediatr Scand, Suppl. 305: 92–99, 1983.—Pulmonary edema is an important feature of many newborn lung diseases, including respiratory distress from severe perinatal asphyxia, heart failure, hyaline membrane disease, pneumonitis from group B β–hemolytic streptococcus, and chronic lung disease (bronchopulmonary dysplasia). Neonatal pulmonary edema often results from increased filtration pressure in the microcirculation of the lungs. This occurs during sustained hypoxia, in left ventricular failure associated with congenital heart disease or myocardial dysfunction, following excessive intravascular infusions of blood, colloid, fat, or electrolyte solution, and in conditions that increase pulmonary blood flow. Low intravascular protein osmotic pressure from hypoproteinemia may predispose infants to pulmonary edema. Hypoproteinemia is common in infants who are born prematurely. Large intravascular infusions of protein-free fluid further decrease the concentration of protein in plasma and thereby facilitate edema formation. Lymphatic obstruction by air (pulmonary interstitial emphysema) or fibrosis (long-standing lung disease) also may contribute to the development of edema. Bacteremia, endotoxemia. and prolonged oxygen breathing injure the pulmonary microvascular endothelium and cause proteinrich fluid to accumulate in the lungs. The risk of neonatal pulmonary edema can be reduced by several therapeutic measures designed to lessen filtration pressure, increase plasma protein osmotic pressure, and prevent or reduce the severity of lung injury.