Surfactant replacement therapy

OBJECTIVE: To analyze and update information about surfactant therapy replacement in newborns with lung diseases. SOURCES: Literature review, including textbooks, meta-analyses, prospective, randomized controlled trials, retrospective assessments and case studies. Literature was reviewed based on the authors clinical and scientific experience regarding surfactant replacement therapy in neonatal lung diseases. SUMMARY OF THE FINDINGS: Surfactant replacement therapy for the neonatal respiratory distress syndrome improves respiratory function, and reduces the need for oxygen supplementation and pressure support ventilation, in addition to minimizing the air leak syndrome. However, the use of surfactant did not prevent the occurrence of other intercurrent diseases such as patent ductus arteriosus, intraventricular hemorrhage, necrotizing enterocolitis, retinopathy of prematurity, and bronchopulmonary dysplasia. The surfactant treatment decreased neonatal mortality up to 40%. The effectiveness of exogenous surfactant on other respiratory diseases with surface film dysfunction, such as meconium aspiration syndrome, pneumonia, acute respiratory distress syndrome and congenital diaphragmatic hernia has not yet been widely accepted. CONCLUSIONS: Surfactant replacement is now considered the standard treatment for newborns with respiratory distress syndrome. We hope that, in the future, new synthetic surfactant preparations will be more effective in treating other infant respiratory diseases.     

Surfactant replacement therapy at birth: final analysis of a clinical trial and comparisons with similar trials

A randomized trial of surfactant replacement therapy at birth was conducted at the University of Rochester between June 1983 and November 1985. Thirty-four premature infants, 25 to 29 weeks' gestational age, received a preventilatory dose of a calf lung surfactant extract in saline prepared at the University of Rochester. A control group of 31 infants received a preventilatory dose of saline alone. The major finding of this trial is that a single preventilatory dose of calf lung surfactant extract reduces the severity of the respiratory distress syndrome during the first 24 hours of life. The beneficial effects, however, are not sustained in many infants and diminish after 24 hours of life. The survival rate was 71% in both the control and surfactant-treated groups. There was a lower incidence of pneumothorax in the surfactant-treated group. There were no differences in the incidence of bronchopulmonary dysplasia, patent ductus arteriosus, and intraventricular hemorrhage. No adverse effects of surfactant replacement therapy were identified. Results of this study suggest that multiple postventilatory doses of surfactant will be required for optimal therapy.     

Surfactant replacement therapy in a pediatric near-drowning case in manure

ABSTRACT: Drowning is defined as suffocation by submersion especially in water and is a leading cause of injury-related death in children. Age groups at greatest risk are toddlers and male adolescents. It is the second most common cause of accidental death in children after road accidents. Treatment consists of resuscitation and stabilization. The use of surfactant after near-drowning in water is reported in the literature in few case reports.We report here a boy whose condition did not get better with conventional treatment, but dramatically improved after surfactant treatment after near-drowning in a fluid with manure.     

Surfactant replacement therapy for neonatal respiratory distress syndrome

Conclusions Surfactant treatment of RDS improves oxygcnation and ventilation whether given immediately after birth or after the onset of the disease. There is also a decrease in associated morbidity (air leak), and improved survival with no significant short term side effects. Information about long term follow-up is limited, but encouraging. The future should bring better surfactants (recombinant DNA human surfactant) and optimization of timing, multiplicity and size of dose, and technique of ventilation. This will allow for the survival of most of the premature infants beyond 25 weeks gestation with minimal morbidity. Surfactant treatment of RDS will go down as a true landmark in the history of neonatology.     

Surfactant replacement therapy in neonatal respiratory distress syndrome

We conducted a prospective, randomized, controlled trial comparing the efficacy of two doses of a reconstituted bovine surfactant (Surfactant TA) in premature infants requiring mechanical ventilation shortly after birth for respiratory distress syndrome. Forty-six infants weighing 1000–1499 g were randomized into two groups: a low-dose group (23 infants given a single dose of 60 mg surfactant lipid/kg) and a high-dose group (23 infants given a single dose of 120 mg/kg). The mean (SD) age at which surfactant was given was 5.5 (±1.2) h in the low-dose group and 6.0 (±1.5) h in the high dose group. Both treatments improved oxygenation (increased arterial-alvcolar PO₂ ratio) with decreased mean airway pressure, the high-dose surfactant having a more beneficial effect in prolonging the response. Infants in the high-dose group had significantly less (P<0.05) incidence of both intraventricular haemorrhage and bronchopulmonary dysplasia. This prospective trial documents that a greater benefit can be obtained by increasing the dose of surfactant (120 mg/kg) beyond 60 mg/kg in the treatment of premature infants with severe respiratory distress syndrome (RDS).Abbreviations RDS respiratory distress syndrome - Surfactant TA Surfactant Tokyo-Akita - 5 kDa 5 kilodaltons - ELISA enzyme-linked immunosorbent assay - PDA patent ductus arteriosus - a/APO₂ arterial-alveolar oxygen tension ratio - MAP mean airway pressure - ^99mIc-DTPA 99m technetium diethylenetriamine pentacetate     

肺表面活性物质治疗新生儿呼吸窘迫综合征的临床对照研究

目的　探讨肺表面活性物质 (PS)治疗新生儿呼吸窘迫综合征 (NRDS)的有效性及临床价值。方法　采用气管内滴注单剂PS治疗NRDS患儿 2 5例 ,并与同期未用PS治疗的 2 5例NRDS患儿进行前瞻性临床对照研究。结果　治疗组在应用PS后 2～ 3h皮肤颜色转红 ,经皮血氧饱和度逐渐升高。 6h后动脉血氧分压 (PaO2 )、动脉 /肺泡血氧分压比值 (a/APO2 )及呼吸机有效指数 (VEI)分别由 ( 48± 14)mmHg( 1mmHg =0 .133kPa)、0 .14± 0 .0 6及 ( 0 .16± 0 .0 9)ml/ (mmHg·kg)上升到 ( 6 5±2 9)mmHg、0 .2 4± 0 .15及 ( 0 .2 9± 0 .16 )ml/ (mmHg·kg) ;而氧合指数 (OI)、吸入氧浓度 (FiO2 )及平均气道压 (MAP)由 11.6± 5 .7、0 .5 9± 0 .13及 ( 15 .6± 3.1)cmH2 O( 1cmH2 O =0 .0 98kPa)逐渐降低至 6 .3±3 .4、0 .47± 0 .10及 ( 13 .5± 2 .4)cmH2 O。经广义线性模型方差分析 ,主效应、分组因素及时间因素对两组PaO2 、a/APO2 、OI、FiO2 、MAP及VEI的值具有明显影响。而分组与时间因素的交互作用无显著影响。治疗组机械通气及氧疗时间较对照组明显缩短 ,二者差异有显著性。结论　PS能有效地改善NRDS患儿肺顺应性及氧合功能 ,缩短需要机械通气及氧疗时间。     

Surfactant replacement therapy: A new risk factor in developing retinopathy of prematurity?

We documented the prevalence of retinopathy of prematurity (ROP) in a group of 46 infants suffering from a moderate or severe respiratory distress syndrome and treated with surfactant replacement therapy (SRT) and 61 controls admitted in the year prior to the institution of SRT. Mortality in the treatment group was lower than in the control group (15.5% versus 23.8;P=0.29). The ROP prevalence in the treatment group was 47.8% and in the control group was 47.8% and in the control group 27.9%. To analyse the contribution of SRT alone to the prevalence of ROP, multivariate analysis using logistic regression technique was used. The odds ratio for SRT was 5.2 with a 95% confidence interval of 1.3–20.7,P=0.02. The prevalence of severe ROP in the surfactant treated group was not increased compared to the control group. From our data we conclude that SRT increases the risk of developing ROP but is not associated with more severe forms of ROP.     

Surfactant replacement therapy in neonates with respiratory failure due to bacterial sepsis

We describe four newborns (gestational ages 29-37 weeks; birthweights 1380-3040 grams) who were mechanically ventilated for respiratory insufficiency because of bacterial sepsis. A beneficial effect of bovine surfactant (Alvofact, dosages 50 or lOOmg/kg) was found, as shown by decreases in mean airway pressures and oxygen demands. No side effects were seen after instillation.     

改良式雾化吸入肺表面活性物质治疗极低体重儿肺炎

目的 观察改良式雾化吸入肺表面活性物质（PS）治疗极低体重儿肺炎的疗效。方法 用固尔苏采用改良式雾化吸入治疗极低体重儿肺炎6例，观察治疗前后血气、肺泡充气程度、临床症状的变化。结果 用药1hPO2和动脉－肺泡氧分压比值（a／APO2）较用药前明显升高，用药后6h，PO2和a／APO2仍高于用药前，差异均有显著意义（P均＜0．05）。用药1hPCO2下降不明显，用药后6hPCO2显著下降，与用药前比较，差异有显著意义（P＜0．05，同时胸部X线显示肺野靛度明显改善，临床症状明显好转。结论 采用改良式雾化吸入治疗极低体重儿肺炎能有效改善肺换气和通气，提高肺泡充气程度。     

Surfactant replacement therapy in neonates less than 32 weeks gestation: Effect on neonatal intensive care resource utilization

Abstract  The effect of synthetic surfactant (Exosurf) replacement on complications from hyaline membrane disease (HMD) in infants <32 weeks gestation and their resource utilization within a neonatal intensive care unit was studied in 1991-92. A control group was selected from infants admitted to the same unit during the preceding 3 years when Exosurf was not available. The infants were controlled for gestation, weight and severity of HMD.
Infants given Exosurf had a significant reduction in the incidence of pulmonary interstitial emphysema (PIE), and a marginal decrease in the incidence of pneumothorax. They required fewer days on the ventilator and consumed less of the scarce financial resources. There was no difference in the mortality rate among the two groups. The changes seen were more evident among those infants between 30 and 31 weeks gestation, compared to those <28 weeks.     

Chlorambucil dosage in frequently relapsing nephrotic syndrome: a controlled clinical trial

A controlled clinical trial was performed using two dosage regimens of chlorambucil to treat children with frequently relapsing nephrotic syndrome. All children concurrently received prednisone (60 mg/m2 on alternate days). Ten children (Group I) were given chlorambucil as a stable dose (0.2 mg/kg/day) for 56 to 60 days, and 11 children (Group II) received increasing doses (0.2 to 0.63 mg/kg/day) for 42 to 77 days. Two children in each group subsequently relapsed. Follow-up averaged 28.6 and 27.2 months in Groups I and II, respectively. Three children in Group II developed infectious complications. The data indicate that a stable dosage regimen for chlorambucil is as effective as an increasing dose regimen in achieving long-term remission of frequently relapsing nephrotic syndrome.