High frequency oscillation for preterm infants with severe respiratory failure

High frequency oscillation (HFO) as rescue treatment for preterm infants with severe respiratory failure has been assessed and prognostic factors identified. Thirty six infants with a median gestational age of 27 weeks were studied. Immediately before transfer to HFO, the infants were receiving an inspired oxygen concentration of > or = 85% and/or a mean airway pressure of > or = 12 cm H2O and had a median alveolar-arterial oxygen gradient (A-aDO2) of 73.28 kPa (range 49.34-89.91). Seventeen infants subsequently died. Comparison of those 17 with the remaining 19 infants demonstrated that respiratory distress syndrome and persistent fetal circulation were associated with a significantly better outcome than pulmonary airleak. The A-aDO2 after two and six hours on HFO was significantly higher in those infants who survived compared with those who died. We conclude that a diagnosis of pulmonary airleak and failure to show early improvement in respiratory status indicate a poor prognosis when HFO is used as rescue treatment.     

Prenatal dexamethasone and exogenous surfactant therapy: surface activity and surfactant components in airway specimens

To explain some of the effects of prenatal glucocorticoid treatment on lung function, surfactant parameters in the airway specimens of ventilator-dependent preterm infants were analyzed. In this double-blind study, the mothers of these infants had received dexamethasone (DEX) or placebo prenatally. Human surfactant was given for the treatment of moderate to severe respiratory distress syndrome. Seventy-six preterm infants with mean gestational age of 29 wk and mean birth weight of 1137 g were studied. The concentrations of surfactant components in epithelial lining fluid (ELF) were analyzed, and the surface activity was measured using a pulsating bubble method. Prenatal DEX treatment increased the responsiveness to exogenous surfactant and decreased the severity of respiratory failure during the first day of life. The treatment had no effect on the concentrations of surfactant phospholipids that were generally high. Prenatal DEX treatment increased the association between phospholipid concentration in ELF and the degree of respiratory failure. Prenatal DEX improved the surface activity of surfactant isolated from airway specimens and tended to increase the ratio of surfactant protein A to phosphatidylcholine among recipients of exogenous surfactant. A subgroup of infants, offspring of mothers with severe hypertension had an abnormally low concentration of surfactant protein A and a poor outcome, despite prenatal DEX treatment or surfactant substitution. Prenatal DEX decreased the concentration of nonsedimentable proteins in ELF and decreased the inhibition of surface activity by these proteins. Our results indicate that improved surfactant function during the first day of life explains some of the beneficial pulmonary effects of prenatal glucocorticoid treatment in preterm infants who are ventilator-dependent.     

Experiences with high-frequency oscillatory ventilation in premature infants with respiratory distress syndrome

BACKGROUND: High-frequency oscillatory ventilation (HFOV) has been used in treating premature infants with respiratory distress syndrome who have a low incidence of ventilation-associated lung injury. Herein, we report our initial clinical experience in using HFOV to treat such infants. METHODS: From October 1996 to February 1997, 10 premature infants with severe respiratory distress syndrome treated with HFOV were retrospectively evaluated. Clinical course and laboratory data collected during treatment were analyzed. Parameters evaluated included patient survival rate, incidence of chronic lung disease and morbidity associated with HFOV usage. RESULTS: The mean gestational age was 29 +/- 2 weeks; mean birth weight, 1,182 +/- 342 g; and mean period of HFOV treatment, 3.4 +/- 1.9 days. One patient died of sepsis due to infective pancarditis. Two patients developed moderate chronic lung disease at 30 days post delivery and in one of these patients, the disease persisted at 36 weeks' of age. The overall survival rate was 90%. No patient developed air-leak syndrome during the course of treatment. CONCLUSIONS: Our initial experience demonstrated that using HFOV in treating premature infants with severe respiratory distress syndrome was safe and effective. The incidence of moderate to severe chronic lung disease or air-leak syndrome following HFOV was low.     

Clinical response to inhaled nitric oxide in persistent pulmonary hypertension of the newborn

We observed clinical response to inhaled nitric oxide (iNO) in 12 neonates with persistent pulmonary hypertension of the newborn (PPHN). Clinical response was defined as a decrease in oxygenation index (OI) by 40%. Ten of 12 neonates had response to iNO showing decrease OI from 46.1+/-7.6 to 14.4+/-6.8 at 1 hour after inhalation. Sustained improvement of OI was achieved in 8 neonates and two neonates were relapsed. In the group of neonates who had OI above 40 (n=7), 6 of them showed the decrease of OI from 66.1+/-4.8 to 18.3+/-8.0 at 1 hour. In two groups, one had OI of 40 or greater, and the other OI of 40 or less, there were no differences in pattern of response and early death rate. The response rates according to underlying diseases were as follows; idiopathic PPHN 100%, respiratory distress syndrome 100%, and diaphragmatic hernia 66.7%. Relapse was observed in one neonate with sepsis caused by pneumonia and in one infant with meconium aspiration syndrome. Two infants showed no response to iNO (one diaphragmatic hernia and one suspected pulmonary hypoplasia). We conclude that iNO therapy could improve oxygenation in high percentage of newborn infants with severe PPHN of various underlying conditions except pulmonary hypoplasia.     

Combined effects of antenatal corticosteroids and surfactant supplementation on the outcome of very low birth weight infants

Antenatal corticosteroids in preterm pregnancy may result in the reduction of the incidence of respiratory distress syndrome (RDS) and neonatal mortality. It is well known that postnatal use of surfactant in very low birth weight (VLBW) infants with RDS results in decreased neonatal morbidity and mortality. To evaluate the additive beneficial effects of combined antenatal corticosteroids and postnatal use of rescue surfactant on the outcome of VLBW infants, we retrospectively reviewed 286 maternal/infant charts of preterm infants with gestational ages 23 to 32 weeks and birth weights 501 to 1500 gm who were born at our institution from 1991 through 1994. Of the 87 (30%) infants who were treated with corticosteroids before birth, 41 (47%) had RDS, and of the 199 (70%) infants who were not treated with corticosteroids before birth, 162 (81%) had RDS (p < 0.001). The infants who had RDS and who were treated with corticosteroids before birth had a decreased incidence of pulmonary air leaks and a decreased need for diuretic therapy. In addition, they had a significant reduction in O2 requirement and ventilator settings as reflected by FIO2, mean airway pressure, ventilator rate, O2 index, and A-aDO2 before they received the first dose of rescue surfactant (p < 0.05 to p < 0.01) in contrast to other VLBW infants who had RDS and who were not treated with corticosteroids before birth. We conclude that antenatal corticosteroid therapy in threatened premature labor combined with the use of postnatal rescue surfactant is associated with a decreased incidence of RDS and may be beneficial for reducing the severity of RDS and improving the eventual outcome of VLBW infants.     

Congenital diaphragmatic hernia: experience with preoperative stabilization and delayed surgery without ECMO and inhaled nitric oxide

Despite many advances in the management of congenital diaphragmatic hernia (CDH), the condition carries a mortality rate of 40-50% usually consequent to pulmonary hypoplasia and/or persistent pulmonary hypertension. Several centers have reported improved survival with preoperative stabilization and delayed surgery, which is now an accepted method of management. This is a retrospective analysis of all neonates with respiratory distress at birth due to CDH who were treated at our institution with neither extracorporeal membrane oxygenation nor nitric oxide being used. The medical records of all neonates with CDH and respiratory distress at birth who were treated at this institution from August 1, 1992 through March 1, 1997 were reviewed. There were 21 patients, 11 male and 10 female. There were 17 full-term and 4 premature infants; two premature infants at 30 and 34 weeks' gestation were not resuscitated because of severe associated congenital anomalies. Surgery was performed from 5 to 144 hr (mean 45 hr) in 18 infants. One infant died during preoperative stabilization from severe pulmonary hypoplasia and pulmonary hypertension and one infant died postoperatively from the same conditions. Seventeen of 19 infants (89.5%) survived and were discharged home. Three infants (17.6%) who failed to thrive due to severe gastroesophageal reflux (GER) required fundoplication. Eleven infants (64.7%) who had sepsis proven by blood culture responded satisfactorily to appropriate antibiotics. Preoperative stabilization and delayed surgery has been a satisfactory form of management in our series. The significant complication was sepsis, which must be addressed.     

Same-day pediatric surgery

HL surfactant was used for vital indications in 12 newborns with respiratory distress syndrome born at 28-36 weeks weighing 1000-2500 g at birth and postgestation age of up to 48 h, without apparent congenital diseases and evident signs of intrauterine infection and with intraventricular hemorrhages no more severe than of the second degree. Control group consisted of 12 babies with similar condition treated similarly but without surfactant. Surfactant HL was administered endotracheally in a dose of 50 mg/kg twice at 12-h interval. Good effect was attained in 4 newborns, stable deterioration in 2, and no effect in 6 children. The majority of artificial ventilation values were virtually the same in both groups, but 2 days after surfactant, FiO2 was significantly lower in the controls than in experimental group (0.37 +/- 0.05 vs. 0.64 +/- 0.4, p < 0.01), and VEI was higher in the controls (0.33 +/- 0.05 vs. 0.18 +/- 0.03, p < 0.05). VR, MAP, FiO2, and oxygenation index decreased slower in the test group than in the controls. The mean duration of treatment with hypoxic gaseous mixtures and artificial ventilation of the lungs in the test vs. control group were 143 +/- 60 and 288 +/- 45 h vs. 45.5 +/- 8.3 and 200.8 +/- 28.5 h, respectively. The incidence of air leakage syndrome was 83% (10 cases) in the test group and 17% (2 cases) in the control group, chronic pulmonary diseases developed in 3 (25%) babies in the test and in 1 (8.3%) in the control group. Seven (67%) children in the test group developed obstructive changes in the lungs vs. 1 child in the control group. One child (test group) died from causes other than pulmonary. Hospital stay was longer in the test group than in control (14.8 +/- 1.7 vs. 8.3 +/- 1.3 days, p < 0.01).     

Morphological investigation of the neonatal lung with respiratory distress syndrome which was maximally distended with Somentor 33 and formalin (author's transl)]

The importance of morphological immaturity of the lung in the development of the respiratory distress syndrome was investigated. Atelectatic lungs of newborns were maximally expanded with a mineral oil of low kinematic viscosity (Somentor 33) or 10% Formalin. With this method, surface active forces of peripheral air spaces should not impede expansion of the lungs. 27 lungs of neonates who died of respiratory distress syndrome and 10 lungs of neonates without primary respiratory problems were examined. Following maximal expansion of the lungs with the respiratory distress syndrome show a hypercellular densely cellular tissue of the pulmonary segments, much like glanduloid hyperplasia with small peripheral air spaces and long distances for diffusion of the respiratory gases. The lungs of newborns without respiratory distress syndromes are well alveolar following expansion and show an optimal morphology for gas diffusion. A lack of a surfactant should have significant consequences in small air spaces.     

The need for inotropic support in a subgroup of infants with severe life-threatening respiratory syncytial viral infection

BACKGROUND: We experienced an unusual complication of life-threatening respiratory syncytial viral disease cardiovascular compromise. Life-threatening respiratory syncytial virus (RSV) infection has predominancy involved with ventilatory support for respiratory distress and/or failure. We performed a retrospective chart review of 20 consecutive infants admitted to the pediatric intensive care unit (PICU) for impending respiratory failure. METHODS: Seventeen required ventilatory support. As part of the infants' initial assessment, blood pressure, distal perfusion [capillary refill time (CRT) > or = 3 sec], decreased peripheral pulses, and peripheral mottling were used to determine cardiovascular compromise. These infants received volume resuscitation either at the referring facility or the PICU until euvolemia was obtained, as determined by central venous pressure (CVP) monitoring (between 3 to 7 cm H20). Nine of the 20 infants did not respond to volume resuscitation alone and required vasopressor support in the form of: Dopamine (7 patients, 5-10 micrograms/kg/min), Dobutamine (2 patients, 5-7 micrograms/kg/min), and one who expired required both Epinephrine (600 ng/kg/min) and Dopamine (10 micrograms/kg/min). The mean ages of these 9 patients were 6.2 +/- 3.4 weeks (range 3-12 weeks), the mean duration of ventilation was 7.2 +/- 4.1 days (range 4-12 days). The mean duration of pharmacologic support was 69.7 +/- 47 hours (range 14-168 hours). The mean ages of RSV+ infants not requiring inotropic support was 19.4 +/- 27.4 weeks (range 1-90 weeks), and mean duration of ventilation was 5.5 +/- 5.9 days (range 2-20 days). RESULTS: The inotrope treated patients were weaned from pharmacologic support prior to extubation, without any hemodynamic deficits. Our experience with this rather high incidence of hemodynamic complications during this RSV epidemic was unexpected. CONCLUSION: These results substantiate the fact that younger patients with RSV disease are at both greater risk for pulmonary complications and cardiovascular deterioration and may thus benefit from pharmacologic support.     

Treatment of neonatal respiratory distress syndrome with Alveofact--results of a prospective observational study

AIM: After registration of the bovine Surfactant Alveofact (Fa. Thomae) for treatment of neonatal respiratory distress syndrome (RDS) an observational study was performed in 47 german neonatal departments to register indication, effectivity, mode of administration and unexpected side effects. METHODS: 680 ventilated preterm infants (gestational weeks 29.5 +/- 2.9; birth weight 1359 +/- 507 g) were enrolled in an uncontrolled clinical study with study-protocol, prospectively defined outcomes and covariates, manual of operation, central control system, biometrical control. RESULTS: Surfactant was applicated at a postnatal age of 2 hours 56 minutes (median). Only 2.9% of newborn infants got the first surfactant doses < 6 min postnatally, 19.4% between 6 ... 60 min and 77.7% > 60 min postnatally. Following 1338 instillations in 76% an improved lung function, in 21% no change and in 3% a worsening was observed. During the study the total dose of surfactant increased. Safety considerations determined by the rate of pulmonary and extrapulmonary complications were similar to data of the literature: pneumothorax 12%, pulmonary interstitial emphysema 11.6%, secondary pneumonia 20.4%, broncho-pulmonary dysplasia 27%, pulmonary hemorrhage 2.1%, peri/intraventricular hemorrhage (degree III/IV) 27.9%, ductus arteriosus persistens 24.4%, sepsis/meningitis 12.4%. During the study the mortality reduces from 31% (first period) to 18% (third period) the mean was 20%. In 44 infants (6.5%) a disturbed ventilation (airway obstruction, overdystension of pulmonary areas, atelectasis) after surfactant administration was observed. CONCLUSION: In RDS the surfactant Alveofact is preferably used therapeutically (rescue mode), it is effective but not free of risk. Its administration needs for a clear indication. New unknown side effects of Alveofact were not observed.     

Bronchopulmonary dysplasia: the pulmonary pathologic sequel of necrotizing bronchiolitis and pulmonary fibrosis

A light and electron microscopic study was carried out in 21 infants in whom the pathologic diagnosis of bronchopulmonary dysplasia had been made. All the infants except two had the respiratory distress syndrome at birth, and all 21 had been treated with respirator and oxygen therapy for various periods of time. The pathologic alterations observed in all the infants studied were primarily damage of the bronchial and bronchiolar ciliary apparatus and mucous membranes, severe necrotizing bronchiolitis, and marked bronchiolar and alveolar fibrosis. These changes were more pronounced in infants who survived the longest period of time. Such inflammatory and fibrotic changes are known to predispose to destruction of lung tissue, emphysema, and pulmonary hypertension. Six of these 21 infants developed symptoms and signs of cardiac atrial or ventricular stress, including cor pulmonale, prior to their demise. These infants were among those that survived the longest periods of time, had the longest exposure to supplemental oxygen, and showed histopathologically severe pulmonary fibrosis and emphysema.     

Diagnosis oligohydramnios-related pulmonary hypoplasia (Potter syndrome): value of portable voiding cystourethrography in newborns with respiratory distress

Potter renal nonfunctional syndrome is an association of facial and limb anomalies, pulmonary hypoplasia, and fetal renal anomalies which lead to marked oligohydramnios, including renal agenesis (true Potter syndrome), renal cystic dysplasia, and obstructive uropathies. Some infants survive long enough to develop severe respiratory distress secondary to pulmonary hypoplasia. The underlying renal disease is often noted only at autopsy. We studied four infants, only one of whom had clinical signs of the renal nonfunction syndrome. Portable voiding cystourethrography revealed a tiny bladder in three infants with cystic dysplasia kidneys (two of these infants had reflux into unused ureters). Bladder hypertrophy and vesicoureteral reflux secondary to posterior uretral valves were noted in the fourth infant.     

Soluble L-selectin plasma concentrations in infants undergoing heart surgery: no association with capillary leak syndrome or need for respiratory support

OBJECTIVE: In critical care patients at risk of developing the acute respiratory distress syndrome (ARDS), low soluble L-selectin (sCD62L) plasma concentrations have been shown to be associated with progression to ARDS and prolonged subsequent mechanical ventilation. This study aimed to determine the usefulness of sCD62L plasma concentrations to identify infants undergoing cardiovascular surgery who are at risk for postoperative pulmonary dysfunction and capillary leaks. DESIGN: Serial measurements of sCD62L plasma concentrations in a cohort of infants with congenital heart disease before, during, and after surgery for 4 consecutive days. SETTING AND PATIENTS: Infants aged 3-337 days undergoing cardiovascular surgery with (N = 27) or without (N = 12) cardiopulmonary bypass in a tertiary care center. RESULTS: sCD62L concentrations before surgery showed a strong correlation with the infant's age (r = 0.77, p < 0.001). During surgery, sCD62L levels dropped from 9.0 +/- 0.7 to 5.6 +/- 0.4 nmol/l (mean +/- SEM; p < 0.001). The minimum sCD62L concentration during and after surgery did not differ between infants operated upon with or without cardiopulmonary bypass (p > 0.1) or in infants who did (N = 10) or did not (N = 29) develop capillary leak syndrome. Whereas capillary leak syndrome was associated with prolonged mechanical ventilation (p < 0.01), there was no relationship between sCD62L concentrations at baseline or at any time thereafter and number of hours on the ventilator(p > 0.1). CONCLUSION: sCD62L concentrations before or after surgery are not apt to identify infants at increased risk of prolonged mechanical ventilation.     

High expression of leptin by human bone marrow adipocytes in primary culture

Inhaled nitric oxide (iNO) has been shown to improve oxygenation in severe persistent pulmonary hypertension of the newborn (PPHN). However, PPHN is often associated with various lung diseases. Thus, response to iNO may depend upon the aetiology of neonatal acute respiratory failure. A total of 150 (29 preterm and 121 term) newborns with PPHN were prospectively enrolled on the basis of oxygenation index (OI) higher than 30 and 40, respectively. NO dosage was stepwise increased (10-80 ppm) during conventional mechanical or high-frequency oscillatory ventilation while monitoring the oxygenation. Effective dosages ranged from 5 to 20 ppm in the responders, whereas iNO levels were unsuccessfully increased up to 80 ppm in the nonresponders. Within 30 min of iNO therapy, OI was significantly reduced in either preterm neonates (51+/-21 vs 23+/-17, P < .0001) or term infants with idiopathic or acute respiratory distress syndrome (45+/-20 vs 20+/-17, P < .0001), 'idiopathic' PPHN (39+/-14 vs 14+/-9, P < .0001), and sepsis (55+/-25 vs 26+/-20, P < .0001) provided there was no associated refractory shock. Improvement in oxygenation was less significant and sustained (OI=41+/-16 vs 28+/-18, P < .001) in term neonates with meconium aspiration syndrome and much less (OI=58+/-25 vs 46+/-32, P < .01) in those with congenital diaphragmatic hernia. Only 21 of the 129 term newborns (16%) required extracorporeal membrane oxygenation (57% survival). Survival was significantly associated with the magnitude in the reduction in OI at 30 min of iNO therapy, a gestational age > or =34 weeks, and associated diagnosis other than congenital diaphragmatic hernia. Conclusion, iNO improves the oxygenation in most newborns with severe hypoxaemic respiratory failure including preterm neonates. However, response to iNO is disease-specific. Furthermore, iNO when combined with adequate alveolar recruitment and limited barotrauma using exogenous surfactant and HFOV may obviate the need for extracorporeal membrane oxygenation in many term infants.     

Inhaled nitric oxide for adult respiratory distress syndrome after pulmonary resection

BACKGROUND: The adult respiratory distress syndrome (ARDS) developing after pulmonary resection is usually a lethal complication. The etiology of this serious complication remains unknown despite many theories. Intubation, aspiration bronchoscopy, antibiotics, and diuresis have been the mainstays of treatment. Mortality rates from ARDS after pneumonectomy have been reported as high as 90% to 100%. METHODS: In 1991, nitric oxide became clinically available. We instituted an aggressive program to treat patients with ARDS after pulmonary resection. Patients were intubated and treated with standard supportive measures plus inhaled nitric oxide at 10 to 20 parts/million. While being ventilated, all patients had postural changes to improve ventilation/perfusion matching and management of secretions. Systemic steroids were given to half of the patients. RESULTS: Ten consecutive patients after pulmonary resection with severe ARDS (ARDS score = 3.1+/-0.04) were treated. The mean ratio of partial pressure of arterial oxygen to the fraction of inspired oxygen at initiation of treatment was 95+/-13 mm Hg (mean +/- SEM) and improved immediately to 128+/-24 mm Hg, a 31%+/-8% improvement (p<0.05). The ratio improved steadily over the ensuing 96 hours. Chest x-rays improved in all patients and normalized in 8. No adverse reactions to nitric oxide were observed. CONCLUSIONS: We recommend the following treatment regimen for this lethal complication: intubation at the first radiographic sign of ARDS; immediate institution of inhaled nitric oxide (10 to 20 parts per million); aspiration bronchoscopy and postural changes to improve management of secretions and ventilation/perfusion matching; diuresis and antibiotics; and consideration of the addition of intravenous steroid therapy.     

Simultaneous determination of urinary catecholamines and 5-hydroxyindoleamines by high-performance liquid chromatography with fluorescence detection

OBJECTIVE: The relationship between bronchopulmonary dysplasia (BPD) and neurodevelopmental outcome after extracorporeal membrane oxygenation (ECMO) has not been extensively reported. We compared the outcomes in a large series of infants with and without BPD after ECMO. STUDY DESIGN: Hospital charts and follow-up records of 145 infants treated with ECMO (1985 through 1990) were reviewed. Complete long-term respiratory and follow-up outcome data were available in 64 infants. BPD occurred in 17 survivors; the remaining 47 did not have BPD. RESULTS: Babies with BPD were more likely to have had respiratory distress syndrome. Mean (+/- SD) age at ECMO initiation was later for the BPD group (127+/-66 vs 53+/-39 hours, p < 0.001), and the duration of ECMO treatment was longer (192+/-68 vs 119+/-53 hours, p < 0.001). Bayley Scales of Infant Development scores at <30 months were lower in infants with BPD (p < 0.001), as were three of four Mullen Scales of Early Learning scores (> or = 30 months, p < 0.001 or p = 0.01). At 57+/-16 months 11 (64%) patients with BPD had mild neurologic disabilities, and 3 (18%) had severe disabilities. At a similar age (53+/-16 months, p = NS) 16 (34%) patients without BPD had mild disabilities, whereas 2 (4%) had severe disabilities (p < 0.01). CONCLUSIONS: The occurrence of BPD after ECMO is associated with adverse neurodevelopmental outcome. Patients with BPD after ECMO merit close long-term follow-up.     

Repetitive conundrums of centromere structure and function

BACKGROUND: Adult participants in randomized controlled trials often have better outcomes than patients who are eligible but not enrolled. OBJECTIVE: To examine whether newborn infants who were allocated to placebo in an investigational drug trial had better outcomes than infants who were eligible but not randomized (eligible NR). Study design: During a randomized controlled trial of antithrombin therapy in premature infants with respiratory distress syndrome, data were collected prospectively on all 76 infants in the eligible NR group. Study outcomes were compared with those of all 61 infants who were randomized to placebo. The same exogenous surfactant was used in all patients. RESULTS: In the placebo group the mean (SD) birth weight was 1201 (314) g, mean (SD) gestational age was 28.8 (2.3) weeks, and 51% were male. In infants in the eligible NR group, mean (SD) birth weight was 1141 (262) g, mean (SD) gestational age was 28.3 (2. 3) weeks, and 58% were male; 57% of infants in both groups had been exposed to steroids before birth. The median duration of mechanical ventilation was reduced from 6.2 days in the eligible NR group to 4. 8 days in the placebo group (P =.008). There was also a trend toward less frequent and less severe intraventricular hemorrhage in trial participants. CONCLUSIONS: These data are consistent with the hypothesis that sick newborn infants may benefit from participation in a randomized controlled trial.     

A comparative study of human immunodeficiency virus culture, polymerase chain reaction and anti-human immunodeficiency virus immunoglobulin A antibody detection in the diagnosis during early infancy of vertically acquired human immunodeficiency virus infection

Asynchrony of delivered and spontaneous breaths in mechanically ventilated infants may impair gas exchange and prolong the need for assisted ventilation. We conducted a randomized, controlled trial of a patient-triggered, flow-synchronized ventilator on 30 preterm infants with respiratory distress syndrome who weighed between 1100 and 1500 gm at birth. Entry criteria included radiographic evidence of respiratory distress syndrome and the need for mechanical ventilation and surfactant replacement therapy. Patients were assigned to either conventional time-cycled, pressure-limited ventilation or patient-triggered, flow-synchronized ventilation in an assist/control mode. Otherwise clinical management was identical. Time to extubation was the primary outcome measure. Patients treated with flow-synchronized ventilation were weaned more rapidly and had a significantly shorter mean time to extubation than those treated with time-cycled, pressure-limited ventilation, 119 versus 271 hours, p = 0.0152. In addition, there was no difference in the rate of complications between the two groups. There were, however, considerable reductions in patient charges of $4344 per patient in the flow-synchronized ventilation group.     

Cell yield. ThinPrep vs. cytocentrifuge

The results of treatment of severe respiratory distress syndrome in premature infants with gestational age < or = 32 weeks are reported. During the two-year period 1991-92, the department participated in both the Osiris study (Exosurf) and the Curosurf 4 study (Curosurf). Five of the 23 infants treated with Exosurf died and 16 survived without major sequelae. 14 of the 25 infants treated with Curosurf died and six survived without major sequelae. Four of the infants treated with Curosurf developed severe retinopathy of prematurity. During the study period this complication occurred in one additional patient who was not eligible for inclusion in the study. The results show the need to study differences in the physiological effects of surfactants more closely, in order both to improve the basis for selection of surfactant for individual patients, and to define the indications for treatment. The results raise the question of whether such studies should continue to include control patients.