Poractant alfa versus beractant for respiratory distress syndrome in preterm infants: a retrospective cohort study

Comparison of porcine versus bovine surfactant in preterm respiratory distress syndrome: Evidence from real-world data. A multicentre collaboration from Karnataka

BACKGROUND & OBJECTIVES

Porcine surfactant (200 mg/kg initial dose) seems to be superior to bovine surfactants (100 mg/kg) in respiratory distress syndrome (RDS). There is limited data on the choice of surfactant from the developing world. Logically, using higher doses of porcine surfactant comes with an additional cost burden. We decided to evaluate the clinical effects of different types of surfactants.

METHODS

A retrospective analysis was conducted from August 2019 to December 2022 in six tertiary centers. Neonates 24-34 weeks of gestation with RDS requiring either porcine (200 mg/kg) or bovine surfactant (100 mg/kg) were enrolled. The proportion of BPD, redosing, and other morbidities in either group were analyzed. The outcomes in preterm ≥28 and <28 weeks subgroups were analyzed.

RESULTS

Of 1149 eligible babies, 302 (26%) received surfactant after stabilization with CPAP. One hundred fifty-eight received porcine, and 144 received bovine surfactant. There was a higher BPD in porcine compared to the bovine group on univariate analysis [24 (15%) vs. 6 (4%); OR: 4; 95% CI: 1.6-10; p = 0.002]. On logistic regression, the gestational age and PDA requiring treatment were independent predictors of BPD, and the type of surfactant and centres did not influence BPD. Redosing [27 (17%) vs. 18 (12%), OR: 1.4; 95% CI: 0.7-2.7; p = 0.2] was not different between both surfactant types. Other morbidities like mortality, air leaks, invasive ventilation, and CPAP duration were also not different between the groups.

CONCLUSION

We could not find a difference in the outcomes of BPD and redosing using porcine surfactant at 200 mg/kg compared to bovine surfactant. Considering the cost burden in the developing world, efficacy needs to be evaluated in randomized clinical trials.

Comparison of efficacy between beractant and poractant alfa in respiratory distress syndrome among preterm infants (28-33+6 weeks gestational age) using the less invasive surfactant administration (LISA) technique: A randomized controlled trial

OBJECTIVE

Exogenous surfactant therapy is vital in managing respiratory distress syndrome (RDS) in preterm infants, with less invasive surfactant administration (LISA) gaining popularity. This study aimed to assess the efficacy and short-term outcomes of LISA using beractant and poractant alfa.

STUDY DESIGN

In a randomized controlled trial, we enrolled preterm infants (28-33+6 weeks) with RDS requiring surfactant. LISA was employed, with beractant at 100 mg/kg or poractant-alfa at 200 mg/kg. Primary outcome was the need for intubation within 72 hours.

RESULTS

Among 120 infants, 3.3% in both groups required intubation within 72 hours (p value 1.00, 95% CI 0.14-6.86). No significant differences in secondary outcomes were noted. However, beractant was significantly more economical than poractant-alfa, with a significantly lower surfactant cost and total care cost for infant hospital stays.

CONCLUSION

Beractant and poractant-alfa exhibit similar efficacy in LISA for preterm infants with RDS. Economic considerations, especially in LMICs, favour beractant. CLINICAL TRIAL REGISTATION: (CTRI/2023/03/050375).

Pulmonary Complications in Premature Infants Using a Beractant or Poractant for Respiratory Distress Syndrome: A Retrospective Cohort Study

OBJECTIVE

Premature infants are at the risk of developing respiratory distress syndrome (RDS). Beractants and poractants are two commonly used natural surfactants. This retrospective cohort study aims to compare the incidence of pulmonary complications between beractant and poractant treatment groups.

STUDY DESIGN

This study evaluated 29 patients treated with beractant and 49 patients treated with poractant. The primary outcome was the incidence of air leak syndrome (ALS) and pulmonary hemorrhage. Secondary outcomes included mortality and pulmonary outcomes, such as mechanical ventilation duration, oxygen dependence duration, fraction of inspired oxygen, and mean airway pressure (MAP) requirement. Logistic regression analyses were conducted to identify independent risk factors for significant primary outcomes.

RESULTS

No significant difference was found in the demographics between the two groups. A significantly higher incidence of pulmonary hemorrhage was observed in the poractant group (14.3 vs. 0.0%, p = 0.038). The difference in the incidence of ALS between the groups was insignificant (p = 0.536). Logistic regression for the incidence of pulmonary hemorrhage identified coagulopathy as the only significant independent risk factor (odds ratio 39.855, 95% confidence interval [2.912-545.537]; p = 0.006). Secondary outcomes in both treatment groups were similar, except that patients in the poractant group had a higher MAP before surfactant therapy (9 vs. 8 cmH2O, p < 0.001).

CONCLUSION

This study showed a significantly higher incidence of pulmonary hemorrhage in the poractant group. Coagulopathy was identified as an independent risk factor for pulmonary hemorrhage. Future long-term prospective studies are essential to establish the temporal and causal relationships between coagulopathy and pulmonary hemorrhage in premature infants receiving surfactant therapy for RDS; hence, there is the need for a screening protocol before surfactant administration.

KEY POINTS

· A higher incidence of pulmonary hemorrhage was found in the poractant group.. · Coagulopathy was the only significant risk factor that was related to the incidence of pulmonary hemorrhage.. · A screening protocol might be useful to avoid pulmonary hemorrhage in infants receiving surfactant..

Comparing the clinical and economic efficiency of four natural surfactants in treating infants with respiratory distress syndrome

Surfactant therapy has revolutionized the treatment of respiratory distress syndrome (RDS) over the past few decades. Relying on a new method, the current research seeks to compare four common surfactants in the health market of Iran to determine the best surfactant according to the selected criteria. The research was a cross-sectional, retrospective study that used the data of 13,169 infants as recorded on the information system of the Iranian Ministry of Health. To rank the surfactants used, the following indicators were measured: re-dosing rate, average direct treatment cost, average length of stay, disease burden, need for invasive mechanical ventilation, survival at discharge, and medical referrals. The CRITIC (criteria importance through intercriteria correlation) method was used to determine the weight of the indicators, and MABAC (multi-attributive border approximation area comparison) was used to prioritize the surfactants. Based on the seven selected indicators in this research (re-dosing rate, average length of stay, direct medical cost per one prescription, medical referral rate, survival at discharge, disability-adjusted life years, number of newborns in need of invasive mechanical ventilation) and using multi-criteria analysis method, Alveofact was identified as the worst surfactant in infants with either more or less than 32 weeks' gestation. So that some criteria were worse in Alveofact group infants than other groups; for example, in the comparison of the Alveofact group with the average of the total population, it was found that the survival rate at discharge was 57.14% versus 66.43%, and the rate of re-dosing was 1.63 versus 1.39. BLES (bovine lipid extract surfactant) was the best alternative for infants more than 32 weeks' gestation, whereas Survanta was identified as best option for infants with less than 32 weeks' gestation. Curosurf showed an average level of functionality in the ranking. This study advises the policy makers in the field of neonatal health to increase the market share of more effective surfactants based on this study and other similar studies. On the other hand, neonatal health care providers are also advised to prioritize the use of more effective surfactants if possible, depending on the clinical conditions and desired improvements.

Poractant alfa versus bovine lipid extract surfactant: prospective comparative effectiveness study

OBJECTIVE

To compare short term respiratory outcomes in preterm infants treated with bovine lipid extract surfactant or poractant alfa.

STUDY DESIGN

Prospective comparative effectiveness cohort study of infants <32 weeks' gestational age requiring surfactant in thirteen centers. Each center provided bovine lipid extract surfactant for a set period of time in the year 2019 and then changed to poractant alfa for the remainder of the year. The primary outcome was total duration of respiratory support.

RESULT

968 infants were included. 494 received bovine lipid extract surfactant and 474 received poractant alfa. No difference was observed in the total duration of respiratory support (mechanical ventilation or non-invasive) (median 38 vs 40.5 days), need to re-dose surfactant, bronchopulmonary dysplasia, survival to discharge, or length of admission.

CONCLUSION

In this pragmatic study, we did not identify any difference in short term outcomes between the groups based on the type of surfactant received.

Comparative efficacy and safety of late surfactant preparations: a retrospective study

OBJECTIVE

Characterize the use, efficacy, and safety of poractant alfa and calfactant surfactants compared to beractant in preterm infants receiving late surfactant.

STUDY DESIGN

We included infants <37 weeks gestational age (GA) discharged from Pediatrix Medical Group-managed neonatal intensive care units (1997-2017). Efficacy and safety outcomes of interest were analyzed.

RESULTS

Of 184,770 infants administered surfactant at any time, 7846 (4.23%) received late surfactant at a median (25th, 75th percentile) PNA of 8 days (3, 22); specifically, 2976 received poractant alfa (38%), 2890 beractant (37%), and 1936 calfactant (25%). We identified no significant differences in composite efficacy or safety outcomes between surfactants in the primary analysis, but 33-36 week GA infants administered poractant alfa had significantly greater odds of developing a safety event.

CONCLUSIONS

Compared to beractant, there is no evidence of overall superior efficacy or safety of poractant alfa.

Evaluation of Different Types of Natural Surfactants by Lung Ultrasound in Respiratory Distress Syndrome

OBJECTIVE

This study aimed to compare the lung ultrasonography (LUS) scores after two different natural surfactant administration as a parameter reflecting lung inflation.

STUDY DESIGN

Preterm infants of 32 gestational weeks and below who were diagnosed with respiratory distress syndrome (RDS) were randomly assigned to be administered either poractant alfa or beractant, prospectively. Serial LUS scans were obtained by an experienced neonatologist in a standardized manner before and after (2 and 6 hours) surfactant administration. The LUS scans were evaluated by protocols based on scores and lung profiles.

RESULTS

Thirty-seven infants received poractant alfa and 36 received beractant. The baseline characteristics and presurfactant LUS scores were similar in groups. The scores were significantly decreased after surfactant administration in both groups (2 hours, p = < 0.001; 6 hours, p = < 0.001). LUS scores in poractant group were significantly lower than beractant group when compared at each time point. At the end of 6 hours, the number of infants with the normal profile was significantly higher in the poractant group (∼65%) than the beractant group (22%).

CONCLUSION

LUS is beneficial for evaluating lung aeration after surfactant treatment in preterm infants with RDS. A better lung aeration can be achieved in the early period with the use of poractant alfa.

Beractant and poractant alfa in premature neonates with respiratory distress syndrome: a systematic review of real-world evidence studies and randomized controlled trials

Findings from previous meta-analyses of randomized clinical trials (RCTs) in premature infants with respiratory distress syndrome (RDS) varied as to whether clinical outcomes differed by type of animal-derived pulmonary surfactant; real-world evidence (RWE) was excluded. We extracted study characteristics and outcomes from full-text articles from a systematic search for studies that compared beractant with poractant alfa for RDS in preterm infants. RWE data were tabulated; RCT data were subjected to meta-analyses. Designs, patient characteristics, and follow-up durations varied widely among studies (4 RWE, 15 RCT). RWE studies with adjusted odds ratios (ORs) found no statistically significant between-treatment differences in outcomes. In RCT meta-analyses, no statistically significant between-treatment differences were observed for death (OR [95% confidence interval], 1.35 [0.98-1.86]), bronchopulmonary dysplasia (1.25 [0.96-1.62]), pneumothorax (1.21 [0.72-2.05]), and air leak syndrome (2.28 [0.82-6.39]). Collectively, outcomes were similar with beractant and poractant alfa in RWE studies and pooled RCTs.

Effect of two different early rescue surfactant treatments on mortality in preterm infants with respiratory distress syndrome

INTRODUCTION

Although current evidence suggests that initial dose of 200 mg/kg poractant alfa reduces mortality in the treatment of respiratory distress syndrome (RDS), these data were obtained in a highly heterogeneous group of patients and neither of them addressed mortality as primary outcome.

OBJECTIVE

The aim of this study was to investigate the effects of poractant alfa and beractant on mortality when administered as early rescue surfactant therapy in very preterm infants.

METHODS

We retrospectively evaluated preterm infants followed in our unit between May 2017 and November 2018 whose gestational age (GA) was ≤28 weeks and received surfactant within the first 2 hours of life. Morbidities and mortality rates were compared between infants who received initial doses of 200 mg/kg poractant alfa and 100 mg/kg beractant.

RESULTS

Data from 200 infants who met the inclusion criteria were analyzed. There were 112 patients in the poractant alfa group and 88 patients in beractant group. Mean gestational age in these groups was 26 ± 2 and 25.8 ± 1.8 weeks (P = 0.45) and mean birth weight was 812 ± 243 and 840 ± 208 g (P = 0.39), respectively. The poractant alfa and beractant groups had similar rates of overall mortality (53.5% vs 56.8%), mortality in first 7 days (30.5% vs 25.8%), and beyond day 7 (16.4% vs 13.3%) (P > 0.05). There were no differences in the incidence of preterm morbidities among the two groups.

CONCLUSION

We were unable to demonstrate the superiority of poractant in terms of mortality in very preterm infants with RDS. These findings need to be supported by multicenter, randomized controlled trials.

Synthetic surfactants with SP-B and SP-C analogues to enable worldwide treatment of neonatal respiratory distress syndrome and other lung diseases

Treatment of neonatal respiratory distress syndrome (RDS) using animal-derived lung surfactant preparations has reduced the mortality of handling premature infants with RDS to a 50th of that in the 1960s. The supply of animal-derived lung surfactants is limited and only a part of the preterm babies is treated. Thus, there is a need to develop well-defined synthetic replicas based on key components of natural surfactant. A synthetic product that equals natural-derived surfactants would enable cost-efficient production and could also facilitate the development of the treatments of other lung diseases than neonatal RDS. Recently the first synthetic surfactant that contains analogues of the two hydrophobic surfactant proteins B (SP-B) and SP-C entered clinical trials for the treatment of neonatal RDS. The development of functional synthetic analogues of SP-B and SP-C, however, is considerably more challenging than anticipated 30 years ago when the first structural information of the native proteins became available. For SP-B, a complex three-dimensional dimeric structure stabilized by several disulphides has necessitated the design of miniaturized analogues. The main challenge for SP-C has been the pronounced amyloid aggregation propensity of its transmembrane region. The development of a functional non-aggregating SP-C analogue that can be produced synthetically was achieved by designing the amyloidogenic native sequence so that it spontaneously forms a stable transmembrane α-helix.

Three-year perinatal outcomes of less invasive beractant administration in preterm infants with respiratory distress syndrome

Objective: To assess the impact of beractant treatment using the less invasive surfactant administration (LISA) technique on perinatal outcomes in a prospective cohort of preterm infants with respiratory distress syndrome (RDS).Design: Single-center prospective study conducted in a Department of Neonatology of a tertiary care university-affiliated hospital in Madrid, Spain.Methods: Preterm infants born at <31 + 6 weeks' gestation attended in the neonatal intensive care unit (NICU) between 2012 and 2016. The main outcome was the need of invasive mechanical ventilation during the first 3 days of life. Beractant (100 mg; 4 mL/kg) was administered using the intubation-surfactant-extubation (INSURE) method during 2012 and 2013, and using the LISA procedure between 2014 and 2016.Results: The study population included 512 infants, 232 in the first period and 280 in the second period. Mechanical ventilation exposure during hospitalization showed a significant reduction in the second study period, with an adjusted OR of 0.61, 95% CI 0.39-0.96. Also, an increase of free-bronchopulmonary dysplasia (BPD) survival was found (adjusted OR 2.14, 95% CI 1.29-3.55). These significant differences in perinatal outcomes were observed only in the group of infants of 26 + 0 to 28 + 6 gestational weeks. The success rate of the first dose of beractant using LISA regarding no need of intubation during the first 3 days of life was 54% increasing to 69% in the group of 26 + 0-28 + 6 weeks of gestation. The success rate regarding free-BPD survival was 63.5% in the whole series of LISA treated patients and 72.4% in the group of 26 + 0-28 + 6 weeks. Oxygen reduction after surfactant administration (OR 39.6, 95% CI 6.1-255.8, p < .001) was predictor of LISA success, whereas LISA failure was an independent factor for air leak (OR 18.92, 95% CI 1.31-272.32, p = .031) and Death or BPD outcome (OR 19.3, 95% IC 2.5-147.4, p = .004). Gestational age was inversely associated with the need of intubation after LISA (OR 0.53, 95% CI 0.32-0.87, p = .013).Conclusions: Beractant administration by LISA technique effective reduced the need of intubation during the first 3 days of life and was associated with an increase in survival-free BPD in the group of infants born at 26 + 0 and 28 + 6 weeks' gestation.

Natural Derived Surfactant Preparation As a Carrier of Polymyxin E for Treatment of Pseudomonas aeruginosa Pneumonia in a Near-Term Rabbit Model

BACKGROUND

Pulmonary surfactant spreads rapidly over the airway epithelium, a property that could be harnessed to transport drugs into the lungs. For efficient drug delivery, an interaction between pulmonary surfactant and the drug to be administered is likely needed. On the other hand, the interaction should not compromise the activity of surfactant or the drug once delivered in vivo. The antibiotics gentamicin (an aminoglycoside) and polymyxin E represent drugs that could benefit from being delivered directly to the lung, thereby increasing local concentrations and reducing systemic side effects. Our aim was to study how the animal-derived surfactant poractant alfa (Curosurf^®) affects the activities of polymyxin E and gentamicin against Pseudomonas aeruginosa.

METHODS

In vitro antimicrobial assays and a neonatal near-term rabbit model were used to evaluate the combinations of antibiotics and surfactant against Pseudomonas aeruginosa.

RESULTS

The bactericidal activity of polymyxin E, but not of gentamicin, against P. aeruginosa was partly reduced in vitro in the presence of poractant alfa. In contrast, in the rabbit model of P. aeruginosa pneumonia, polymyxin E administrated together with surfactant was superior in lowering the bacterial load in the lungs compared to polymyxin E alone, without affecting plethysmographically recorded lung compliance.

CONCLUSIONS

The results suggest that polymyxin E interacts with poractant alfa, which reduces the antibacterial effect in vitro. However, when polymyxin E mixed with surfactant is used in the in vivo pneumonia model, increased bactericidal effect was observed. This may be due to a more efficient spreading mediated by interactions between polymyxin E and surfactant. These results warrant further studies of surfactant preparations for drug delivery against lung infections.

Poractant Alfa Versus Beractant for Neonatal Respiratory Distress Syndrome: A Retrospective Cost Analysis

OBJECTIVES The objectives of this study were to determine the average medication cost per patient of poractant alfa and beractant, and to compare the outcomes of treatment with these agents.

METHODS We conducted a retrospective, observational, cohort study of patients who received surfactant, before and after an institutional formulary change from beractant to poractant alfa. The primary outcome was the average medication cost per case. Secondary measures were clinical outcomes, including duration of respiratory support, length of hospital stay, and the occurrence of complications.

RESULTS A total of 114 patients were enrolled; 38 were treated with poractant alfa and 76 patients were treated with beractant. Baseline characteristics were similar between groups. The average medication cost per patient was $1756.44 ± $1030.06 and $1329.78 ± $705.64 for poractant alfa and beractant, respectively (p = 0.011). Patients treated with poractant alfa had a shorter length of stay (45.0 ± 30.5 days) than patients treated with beractant (65.1 ± 37.1 days) (p = 0.010). Rates of pneumothoraces, pulmonary hemorrhage, necrotizing enterocolitis, intraventricular hemorrhage, and mortality did not differ significantly between groups.

CONCLUSIONS We found an unanticipated increase in drug cost with poractant alfa compared to beractant.

Comparison of the Pharmacoeconomics of Calfactant and Poractant Alfa in Surfactant Replacement Therapy

OBJECTIVE To compare the pharmacy costs of calfactant (Infasurf, ONY, Inc.) and poractant alfa (Curosurf, Chiesi USA, Inc., Cary, NC).

METHODS The University of South Alabama Children's and Women's Hospital switched from calfactant to poractant alfa in 2013 and back to calfactant in 2015. Retrospectively, we used deidentified data from pharmacy records that provided type of surfactant administered, gestational age, birth weight, and number of doses on each patient. We examined differences in the number of doses by gestational ages and the differences in costs by birth weight cohorts because cost per dose is based on weight.

RESULTS There were 762 patients who received calfactant and 432 patients who received poractant alfa. The average number of doses required per patient was 1.6 administrations for calfactant-treated patients and 1.7 administrations for poractant alfa-treated patients, p = 0.03. A higher percentage of calfactant patients needed only 1 dose (53%) than poractant alfa patients (47%). The distribution of the number of doses for calfactant-treated patients was significantly lower than for the poractant alfa-patients, p &lt; 0.001. Gestational age had no consistent effect on the number of doses required for either calfactant or poractant alfa. Per patient cost was higher for poractant alfa than for calfactant in all birth weight cohorts. Average per patient cost was $1160.62 for poractant alfa, 38% higher than the average per patient cost for calfactant ($838.34). Using poractant alfa for 22 months is estimated to have cost $202,732.75 more than it would have cost if the hospital had continued using calfactant.

CONCLUSION Our experience showed a strong pharmacoeconomic advantage for the use of calfactant compared to the use of poractant alfa because of similar average dosing and lower per patient drug costs.

Comparison of efficacy and safety of two available natural surfactants in Iran, Curosurf and Survanta in treatment of neonatal respiratory distress syndrome: A randomized clinical trial

Introduction

The benefit of surfactant prescription for respiratory distress syndrome (RDS) has been approved. Curosurf and Survanta are two commonly used natural surfactants in Iran. Previous studies did not report priority for one of these two drugs. The present study aimed to compare the effectiveness and safety of Curosurf and Survanta in treatment of RDS.

Methods

In this randomized clinical trial, neonates were born with RDS diagnosis in two governmental and referral hospitals of Tehran (the capital of Iran) in 2014 were randomly selected. Neonates were randomly assigned into two groups receiving 100 mg/kg Curosurf or Survanta as soon as possible after randomization. Complications, mortality and needing the second dose were compared between the two groups.

Results

A total 112 patients with the mean gestational age of 32.59 ± 3.39 weeks were evaluated (56 patients in each group). There were no significant differences regarding birth weight, gestational age, delivery method, and parity between the two groups (P > 0.05). The complications were occurred in 18 neonates (32.1%) of Curosurf group and 20 neonates (35.7%) of Survanta group (RR = 0.922, 95% CI = 0.617–1.379). There were no significant differences regarding complications, mortality, and needing nasal CPAP and endotracheal tube between the two groups. In the neonates with gestational age of 29–32 weeks the IVH and NEC incidence were significantly more in Curosurf group compared to Survanta group (27.8% vs 0% and 22.3% vs 0%, P < 0.05).

Conclusion

There was no significant difference in complications or mortality between those two groups; however Curosurf was associated with less need of ET tube (in >32 birth weeks subgroup) and NCPAP (in 29–32 birth weeks subgroup) (p = 0.008). Further evaluations with longer follow-up duration are needed for comparing these two surfactants.

Comparison of Three Different Administration Positions for Intratracheal Beractant in Preterm Newborns with Respiratory Distress Syndrome

BACKGROUND

The aim of this study was to compare the efficacy and adverse effects of various intratracheal beractant administration positions in preterm newborns with respiratory distress syndrome.

METHODS

This study was performed on preterm newborns with respiratory distress syndrome. The inclusion criteria were being between 26 weeks and 32 weeks of gestational age, having a birth weight between 600 g and 1500 g, having received clinical and radiological confirmation for the diagnosis of respiratory distress syndrome (RDS) within 3 hours of life, having been born in one of the centers where the study was carried out, and having fractions of inspired oxygen (FiO2) ≥ 0.40 to maintain oxygen saturation by pulse oximeter at 88-96%. Beractant was administered in four positions to Group I newborns, in two positions to Group II, and in neutral position to Group III.

RESULTS

Groups I and II consisted of 42 preterm infants in each whereas Group III included 41 preterm infants. No significant differences were detected among the groups with regards to maternal and neonatal risk factors. Groups were also similar in terms of the following complications: patent ductus arteriosus (PDA), pneumothorax, intraventricular hemorrhage (IVH), chronic lung disease (CLD), retinopathy of prematurity (ROP), necrotising enterocolitis (NEC), death within the first 3 days of life, death within the first 28 days of life, and rehospitalization within 1 month after discharge. Neither any statistically significant differences among the parameters related with surfactant administration, nor any significant statistical differences among the FiO2 levels and the saturation levels before and after the first surfactant administration among the groups were determined.

CONCLUSION

In terms of efficacy and side effects, no important difference was observed between the recommended four position beractant application, the two position administration, and the neutral position.

Liposome Delivery Systems for Inhalation: A Critical Review Highlighting Formulation Issues and Anticancer Applications

This is a critical review on research conducted in the field of pulmonary delivery of liposomes. Issues relating to the mechanism of nebulisation and liposome composition were appraised and correlated with literature reports of liposome formulations used in clinical trials to understand the role of liposome size and composition on therapeutic outcome. A major highlight was liposome inhalation for the treatment of lung cancers. Many in vivo studies that explored the potential of liposomes as anticancer carrier systems were evaluated, including animal studies and clinical trials. Liposomes can entrap anticancer drugs and localise their action in the lung following pulmonary delivery. The safety of inhaled liposomes incorporating anticancer drugs depends on the anticancer agent used and the amount of drug delivered to the target cancer in the lung. The difficulty of efficient targeting of liposomal anticancer aerosols to the cancerous tissues within the lung may result in low doses reaching the target site. Overall, following the success of liposomes as inhalable carriers in the treatment of lung infections, it is expected that more focus from research and development will be given to designing inhalable liposome carriers for the treatment of other lung diseases, including pulmonary cancers. The successful development of anticancer liposomes for inhalation may depend on the future development of effective aerosolisation devices and better targeted liposomes to maximise the benefit of therapy and reduce the potential for local and systemic adverse effects.

[Apllication of nasal synchronous intermittent mandatory ventilation in premature infants with severe respiratory distress syndrome after extubation]

OBJECTIVE

To study the clinical efficacy of nasal synchronous intermittent mandatory ventilation (nSIMV) in premature infants with severe respiratory distress syndrome (RDS) after extubation.

METHODS

A retrospective analysis on the clinical date of 126 premature infants with severe RDS who were hospitalized in the NICU between January 2013 and May 2015 was performed. Sixty-one premature infants who were hospitalized in the NICU between January 2013 and March 2014 received nasal continuous positive airway pressure (nCPAP) (nCPAP group) and 65 premature infants who were hospitalized in the NICU between April 2014 and May 2015 received nSIMV (nSIMV group). The blood gas analysis indexes, the rate of extubation failure, the causes of extubation failure and the incidence of complications were compared between the two groups.

RESULTS

After 4 hours of treatment, the pH value, PaO2, SaO2 and oxygenation index in the nSIMV group were significantly higher than in the nCPAP group (P<0.05), meanwhile, the PaCO2 in the nSIMV group were significantly lower than in the nCPAP group (P<0.05). The rates of extubation failure in the nSIMV and nCPAP groups were 9% (6/65) and 30% (18/61) respectively (P<0.05). The extubation failure in the nSIMV and nCPAP groups was caused by hyoxemia (2% vs 5%; P>0.05), hypercapnia (6% vs 11%; P>0.05) and apnea (2% vs 13%; P<0.05). There were no differences in respirator support time, full enteral feeding time, the time to regain birth weight and the length of hospitalization between two groups (P>0.05). After treatment, the incidence of abdominal distension in the nSIMV group was significantly lower than in the nCPAP group (9% vs 30%; P<0.05) and there were no differences in the incidences of feeding intolerance, necrotizing enterocolitis, intraventricular hemorrhage, retinopathy of prematurity and bronchopulmonory dysplasia between the two groups.

CONCLUSIONS

nSIMV for premature infants with severe RDS after extubation not only significantly improves lung function and reduces the rate of extubation failure, also results in a lower incidence of gastrointestinal side effects and does not increase the incidence of complications.

Biophysical activity of animal-derived exogenous surfactants mixed with rifampicin

Exogenous pulmonary surfactant is a potential delivery system for topical medications via the conducting airways. Due to the sensitivity to inactivation of surfactant, mutual interaction with the shipped drug should be evaluated. Little is known about the interactions between surfactant and antimicrobial drugs. The aim of the present study was to evaluate whether biophysical properties of animal-derived surfactants are modified by the bactericidal antibiotic rifampicin. An intracellular activity and a broad antimicrobiotic spectrum toward Gram-negative and Gram-positive bacteria make rifampicin an interesting substance against pulmonary infections. Curosurf® (porcine surfactant from minced lungs) and Survanta® (bovine surfactant extract) were diluted to 2.5-5.0 mg/ml of phospholipids in 0.9 % NaCl and rifampicin (RIF) was added at 1, 5, and 10 % (w/w). Minimum (γ(min)) and maximum (γ(max)) surface tension of a cyclically compressed bubble in the mixture was assessed with a pulsating bubble surfactometer. After 5 min, γ(min) of Survanta at a concentration of 3 mg/ml was significantly increased after addition of 5 and 10 % RIF (both p < 0.001). At 1 % RIF, the γ(min) of Survanta was ≈10 mN/m and this value was not significantly different to that of Survanta alone. The γ(min) of Curosurf at 3 mg/ml was increased with 10 % RIF (p < 0.001), but not with 1 and 5 %. At 5 mg/ml Survanta was inhibited by 10 % RIF (p < 0.05), while γ(min) of Curosurf was low (<5 mN/m) in all mixtures. In conclusion, Curosurf and Survanta interfere with RIF in a concentration-dependent manner. At the appropriate phospholipid concentration, especially porcine-derived surfactant is able to retain good surface activity when mixed with antibiotics.