Treatment Of Meconium Aspiration Syndrome Research Articles

Role of budesonide inhalation in treatment of meconium-aspiration syndrome

Background and aim Meconium-aspiration syndrome (MAS) is a common cause of respiratory distress. MAS is a serious disease that affects neonates born through meconium-stained amniotic fluid. The pathophysiology of MAS is multifactorial, inflammation has an important role in MAS, so anti-inflammatory drugs like corticosteroids may be effective in the treatment of MAS. Budesonide is a nonhalogenated glucocorticoid that can reduce vascular permeability, inhibit secretion of mucus, relieve edema and spasm, and help pulmonary ventilation. In this study we aimed to find out the effect of early nebulized budesonide in the treatment of MAS. Patients and methods This was a prospective study conducted during the period from October 2017 to July 2018 at El-Minia General Hospital and Al-Azhar University Hospital, Assiut. Intervention: budesonide inhalation in a dose of 50 mg every 12 h till clinical recovery, whichever was earlier. Results The present study revealed that nebulized budesonide improves the clinical outcome of newborns with MAS in terms of lowering the duration of O2 dependency, duration of respiratory distress, duration of hospital stay, duration of radiograph clearance, time for full feeding (P<0.001), and thus early discharge from the NICU. Conclusion Early nebulized budesonide is effective in treating MAS and has high safety with almost no short-term complications.

Surfactant Lung Lavage versus Standard Treatment for Meconium Aspiration Syndrome

Abstract Background: To evaluate diluted surfactant lung lavage as a therapy for severe meconium aspiration syndrome. Aim of Study: The aim of this study is to evaluate the efficacy and outcome of lung lavage using diluted surfactant compared to standard protocol for treatment of meconium aspiration syndrome. Patients and Methods: This was a prospective interven-tional study involved 24 patients with severe meconium aspiration syndrome divided into two equal groups one received the standard care in the form of high frequency ventilation and the second group received pulmonary lavage using diluted surfactant in addition to the standard care. Pulmonary lavage was done using of 15ml/kg of surfactant diluted to concentra-tion of 5mg of phospholipids/1ml of 0.9% NaCl divided into four equal aliquots. Results: On comparing both groups patients managed by pulmonary lavage using diluted surfactant showed significant improvement in PCO2 and mean airway pressure occurred 6 hours after lavage while improvement in PO2, oxygenation index and arterial-alveolar oxygen gradient occurred 24 hours after lavage. The duration of mechanical ventilation, oxygen therapy and hospital stay were shorter in the surfactant group. There was no difference between both groups in the incidence of complications, need for ECMO or death. Conclusion: Surfactant lung lavage is a safe and effective therapy for severe meconium aspiration syndrome.

High Frequency Oscillatory Ventilation Versus Conventional Ventilation in Management of Neonatal Meconium Aspiration syndrome

Meconium aspiration syndrome (MAS) is complex respiratory disease of the term and near-term neonate, which keeps on putting a significant weight on neonatal escalated care assets around the world. The point of this examination was appraisal of high recurrence oscillatory ventilation versus traditional ventilation in administration of neonatal meconium desire, Method: This imminent randomized controlled preliminary included 50 infants admitted to NICU with meconium yearning (MAS), were isolated into 2 gatherings: Group 1: 25 cases treated by customary mechanical ventilation (CMV), Group 2: 25 cases treated by high-recurrence oscillatory ventilator (HFOV). All included patients were exposed to full history taking, total clinical assessment, and research center appraisal. Changes in the oxygenation work markers was utilized for checking patients' reaction as: Fraction of motivation O2 (FiO2), Oxygenation list (OI), blood vessel oxygen pressure/alveolar blood vessel oxygen strain (a/ApO2), at 2, 12, 24, 48 h of treatment. Results: This investigation included 27 guys (54%) and 23 females (46%), the mean gestational age was 37.82±2.6 weeks, CMV gathering, had a measurably longer span of ventilation time (CMV: 7.24±0.65 days, HFOV: 4.23±1.37 days, p < 0.001), longer oxygen treatment (CMV: 15.39±2.44 days, HFOV: 11.76±5.32 days, p < 0.001), and longer season of hospitalization (CMV: 22.17±4.53 days, HFOV: 17.92±12.6 days, p < 0.001). End: Our outcomes demonstrated that HFOV seems to offer extra favorable circumstances contrasted with CMV in the treatment of MAS, by lessening the length of mechanical ventilation, and span of hospitalization, anyway it didn't influence the death rate.

Bronchoalveolar Lavage to Treat Neonatal Meconium Aspiration Syndrome Under Monitoring of Lung Ultrasound Based on a Prospective Case Series Study

Objectives: This study investigated the efficacy and safety of bronchoalveolar lavage (BAL) under lung ultrasound (LUS) monitoring for the treatment of meconium aspiration syndrome (MAS). Methods: A total of 120 patients were randomly divided into 2 groups: a BAL group (70 patients) and a control group (50 patients). Patients in the BAL group received an injection of lavage fluid through an endotracheal tube. After each lavage, LUS was performed to assess lung pathological changes. The control group underwent the traditional treatment. The rate of invasive and/or noninvasive ventilator use, time of ventilator use, incidence of pulmonary hypertension of the newborn (PPHN) and/or incidence of pneumothorax, duration of hospitalization of pediatric patients, hospitalization expenses and mortality were compared between the 2 groups. Results: Compared with the control group, MAS patients in the BAL group had (1) a significantly lower rate of invasive ventilator use (reduced by 57.7%, P < 0.001), (2) a significantly shortened duration of invasive ventilator treatment (reduced by 84.6%, P < 0.001), (3) a significantly reduced incidence of PPHN and/or pneumothorax (reduced by 84.6%, P < 0.001), (4) a reduced rate of mortality (from 2% to 0%), (5) a significantly shortened duration of hospitalization (reduced by 30.1%, P < 0.001), (6) significantly reduced hospitalization expenses (reduced by 42.6%, P < 0.001), and (7) stable vital signs during lavage among all patients, with no adverse effects. Conclusions: Treatment of MAS using BAL under LUS monitoring showed remarkable efficacy without adverse effects.

Recombinant Human Superoxide Dismutase and N-Acetylcysteine Addition to Exogenous Surfactant in the Treatment of Meconium Aspiration Syndrome.

This study aimed to evaluate the molecular background of N-acetylcysteine (NAC) and recombinant human superoxide dismutase (rhSOD) antioxidant action when combined with exogenous surfactant in the treatment of meconium aspiration syndrome (MAS), considering redox signalling a principal part of cell response to meconium. Young New Zealand rabbits were instilled with meconium suspension (Mec) and treated by surfactant alone (Surf) or surfactant in combination with i.v. NAC (Surf + NAC) or i.t. rhSOD (Surf + SOD), and oxygen-ventilated for 5 h. Dynamic lung-thorax compliance, mean airway pressure, PaO2/FiO2 and ventilation efficiency index were evaluated every hour; post mortem, inflammatory and oxidative markers (advanced oxidation protein products, total antioxidant capacity, hydroxynonenal (HNE), p38 mitogen activated protein kinase, caspase 3, thromboxane, endothelin-1 and secretory phospholipase A2) were assessed in pulmonary tissue homogenates. rhSOD addition to surfactant improved significantly, but transiently, gas exchange and reduced levels of inflammatory and oxidative molecules with higher impact; Surf + NAC had stronger effect only on HNE formation, and duration of treatment efficacy in respiratory parameters. In both antioxidants, it seems that targeting reactive oxygen species may be strong supporting factor in surfactant treatment of MAS due to redox sensitivity of many intracellular pathways triggered by meconium.

Protection of Meconium-Induced Lung Epithelial Injury by Protease Inhibitors

Earlier work form this laboratory showed that exposure of alveolar epithelial cells (AECs) to meconium caused significant cell detachment and that meconium-induced detachment of cells was prevented by a protease inhibitor cocktail. Therefore, it was hypothesized that protease inhibitors might protect AEC monolayers against meconium-induced collapse of epithelial barrier function both in vitro and in vivo. To investigate this theory in vitro, albumin flux was measured across cultured, confluent monolayers of human type II derived cell line A549 on microporous filter inserts. Human meconium was collected from seven healthy full-term neonates and the samples were pooled and diluted prior to analysis. Exposure of AECs to 5% human meconium increased albumin flux across the cultured AEC monolayers, but the increase was significantly blocked by protease inhibitors (P<0.001). In C57/BL6 mice, intratracheal instillation of 5% human meconium increased the passage of Evans Blue Dye (EBD) from the vascular compartment into the alveolar spaces, measured in bronchoalveolar lavage (BAL) fluid after intravenous injection of EBD. Moreover, intratrachial coinstillation of protease inhibitors prevented the meconium-induced increase in EBD passage into BAL fluid (P<0.01). The data presented herein clearly demonstrate that protease inhibitors protect AEC barrier function against meconium-induced injury, and suggest the future possibility of using protease inhibitors in the treatment of meconium aspiration syndrome.

Clinical efficacy of porcine pulmonary surfactant combined with budesonide suspension intratracheal instillation in the treatment of neonatal meconium aspiration syndrome

To study the clinical efficacy of porcine pulmonary surfactant (PS) combined with budesonide suspension intratracheal instillation in the treatment of neonatal meconium aspiration syndrome (MAS). Seventy neonates with MAS were enrolled for a prospective study. The neonates were randomly assigned to PS alone treatment group and PS+budesonide treatment group (n=35 each). The PS alone treatment group was given PS (100 mg/kg) by intratracheal instillation. The treatment group was given budesonide suspension (0.25 mg/kg) combined with PS (100 mg/kg). The rate of repeated use of PS in the PS+ budesonide group was significantly lower than that in the PS alone group 12 hours after treatment (p<0.05). The improvement of PaO2/FiO2, TcSaO2, PaO2, and PaCO2 in the PS+ budesonide group was significantly greater than that in the PS alone group 6, 12, and 24 hours after treatment (p<0.05). The chest X-ray examination showed that the pulmonary inflammation absorption in the PS+ budesonide group was significantly better than that in the PS alone group 48 hours after treatment (p<0.05). The incidence of complications in the PS+budesonide group was significantly lower than that in the PS alone group (p<0.05), and the average hospitalization duration was significantly shorter than that in the PS alone group (p<0.01). PS combined with budesonide suspension intratracheal instillation for the treatment of neonatal MAS is effective and superior to PS alone treatment.

The Role of Surfactant Therapy in Nonrespiratory Distress Syndrome Conditions in Neonates.

While treatment of respiratory distress syndrome (RDS) with surfactant in premature neonates is well established, evidence for its use in non-RDS conditions, especially in the term neonate, has been less abundant. The last published review on a PubMed search was in 2001. In this review, we comprehensively and critically evaluated the evidence from the literature regarding the use of surfactant in specific non-RDS disorders in neonates. Surfactant administered as a bolus should be considered in the treatment of meconium aspiration syndrome with progressive respiratory failure. While controversial in congenital diaphragmatic hernia, it should be considered in Group B streptococcal pneumonia. As evidence evolves, we anticipate the broader application and more routine use of surfactant therapy for respiratory failure because of causes other than RDS.

Antibiotic administration for prevention or treatment of meconium aspiration syndrome in neonates: A systematic review

Objectives: To conduct a systematic review of the clinical trials evaluating the role of antibiotics for prevention or treatment of meconium aspiration syndrome (MAS). Methods: We searched several electronic databases including MEDLINE, EMBASE, CINAHL, SCOPUS (until September 2013), and CENTRAL (until August 2013). Additional citations were retrieved from the bibliographies of the selected articles. Studies were included if they were: Randomized or quasi-randomized trials, compared use of antibiotics with no antibiotics for treatment or prevention of MAS, and reported on clinical outcomes in the neonatal period. Results: Four randomized controlled trials (RCTs) were identified; three studies enrolled subjects for treatment of MAS and one study evaluated the prophylactic use of antibiotics in infants exposed to meconium stained amniotic fluid (MSAF). These trials enrolled 695 infants, with the duration of antibiotics between 3 and 7 days. All studies excluded subjects considered to be at higher risk for neonatal sepsis at onset. There were no differences noted for the outcomes of infection rates (relative risk [RR] [95% confidence interval: 0.85 [0.42, 1.73] for clinical sepsis, and 0.93 [0.36, 2.40] for culture-proven sepsis), need for mechanical ventilation (RR: 1.39 [0.68, 2.82]), air leaks syndrome (RR: 1.65 [0.68, 3.99]), hospital stay (mean difference − 0.34 days [−1.13, 0.45]), or mortality (RR: 1.25 [0.36, 4.39]) between the intervention and control groups. Conclusions: In neonates at low-risk for sepsis, insufficient evidence exists to support the routine use of antibiotics following exposure to MSAF or for the treatment of for suspected MAS. We discuss the implications and limitations of review findings for clinical practice.

Anti-inflammatory treatment of meconium aspiration syndrome: Benefits and risks

Meconium aspiration syndrome (MAS) is a major cause of respiratory insufficiency in the term and post-term newborns. There are several pathomechanisms participating in this disorder, particularly the airway obstruction, surfactant dysfunction, inflammation, lung edema, pulmonary vasoconstriction and bronchoconstriction. Inflammatory changes resulting from meconium aspiration cause severe impairment of lung parenchyma and surfactant, and influence the reactivity of both vascular and airway smooth muscle. Therefore, anti-inflammatory drugs may be of benefit in the management of MAS. This article reviews the pharmacological actions and side effects of various anti-inflammatory drugs used up to now in the experimental models of MAS and in the treatment of newborns with meconium aspiration.

Surfactant Lavage Therapy for Meconium Aspiration Syndrome: A Systematic Review and Meta-Analysis

Background: Lung lavage with diluted surfactant has emerged as an innovative treatment for meconium aspiration syndrome (MAS). However, the treatment effect has not yet been fully established. Objective: To investigate the effects of surfactant lavage therapy for MAS by a systematic meta-analysis. Methods: Relevant studies were identified by database searches in MEDLINE (from 1950), EMBASE (from 1980), and CENTRAL, up to June 2010, and by additional hand searches. Meta-analyses were separately conducted for randomized controlled trials (RCTs) and non-randomized controlled studies (NRSs). Risk of bias was assessed and clinical as well as statistical heterogeneities were also investigated in explaining the potential bias. Results: Two RCTs (87 patients) and eight NRSs (178 patients) were identified. From the results of the meta-analysis of RCTs, surfactant lavage significantly decreased death or the need for extracorporeal membrane oxygenation (RR 0.34, 95% CI 0.11, 0.99). An interventional benefit was indicated for other outcomes, although it was not statistically significant based only on the two RCTs. Results from the analysis of outcomes from NRSs are consistent with those from RCTs and demonstrated a beneficial effect, which could be considered as supporting evidence. Conclusions: Lung lavage with diluted surfactant appeared to improve the clinical outcome in infants with MAS. Given that less than 100 infants were included in the two RCTs, the findings of this study may still be regarded as insufficient evidence. Further research will be needed to confirm the benefit as well as to refine the lavage technique.

Anti-Inflammatory Drugs in the Treatment of Meconium Aspiration Syndrome

Anti-Inflammatory Drugs in the Treatment of Meconium Aspiration Syndrome Meconium aspiration syndrome (MAS) is a major cause of respiratory distress in both the term and post-term neonates. Obstruction of the airways, dysfunction of pulmonary surfactant, inflammation, lung edema, pulmonary vasoconstriction and bronchoconstriction participate in the pathogenesis of this disorder. Since the inflammatory changes associated with meconium aspiration cause a severe impairment of the lung parenchyma including surfactant and influence the reactivity of both vascular and airway smooth muscle, administration of anti-inflammatory drugs may be of benefit also in the management of MAS. This article reviews effects of various anti-inflammatory drugs used in experimental models of MAS as well as in the treatment of newborns with meconium aspiration.

Newborn Respiratory Disorders

Newborn Respiratory Disorders

Effective Lavage Volume of Diluted Surfactant Improves the Outcome of Meconium Aspiration Syndrome in Newborn Piglets

Meconium aspiration syndrome (MAS) is one of the top causes of severe respiratory failure in neonates. This study was designed to investigate the effective volume of therapeutic bronchoalveolar lavage (BAL) with diluted surfactant in the treatment of MAS in newborn piglets. Human meconium was instilled in 24 piglets to induce MAS, and the piglets were randomly divided into four groups: 1) control, no lavage; 2) lavage-10, BAL with diluted surfactant (5 mg/mL, Survanta) 10 mL/kg in two aliquots; 3) lavage-20, 20 mL/kg in two aliquots; 4) lavage-30, 30 mL/kg in two aliquots. Cardiopulmonary parameters were monitored, and the lung tissue was histologically examined after experiments. The changes in oxygenation and lung compliance of lavage-20 and lavage-30 groups were significantly better than control and lavage-10 groups (p < 0.05), but there was no significant difference between lavage-20 and lavage-30 groups. The lung injury scores were significantly lower in the dependent site of lavage-20 and lavage-30 groups than the other two groups. In conclusion, using 20 mL/kg diluted surfactant in two aliquots to perform therapeutic BAL was as effective as 30 mL/kg in improving the pathophysiological outcomes in MAS and may warrant consideration clinically in treating MAS.

Effects of dexamethasone on cardiovascular functions in acute phase in meconium‐injured rabbits

Because cardiovascular functions and their control mechanisms may be influenced by meconium aspiration and by treatment, cardiovascular parameters including heart rate variability (HRV) were evaluated after meconium instillation and treatment with dexamethasone. Adult rabbits were anesthetized, paralyzed, and artificially ventilated. Meconium suspension (25 mg/mL, 4 mL/kg) was instilled intratracheally to induce respiratory failure. Thirty minutes later, animals received i.v. dexamethasone (0.5 mg/kg; dexa group, n = 6) or were left without treatment (control group, n = 5). All animals were ventilated for an additional 5 h. Mean heart rate (MHR), mean blood pressure (MBP), central venous pressure (CVP), and time and spectral analyses of HRV were registered and evaluated. Blood gases were measured and right-to-left pulmonary shunts (RLS) calculated. Immediately after meconium instillation, MBP, CVP, and RLS increased and MHR decreased (P < 0.05). MHR and MBP were restored within several minutes, while CVP and RLS remained high until the end of experiment. Thirty minutes after meconium instillation, slightly but non-significantly higher spectral powers in all frequency bands of HRV were found (P > 0.05). Dexamethasone treatment enhanced oxygenation (P < 0.05) and slightly reduced PaCO(2) (P > 0.05), increased parasympathetic activity expressed by mean squared successive difference and decreased spectral power in the very low frequency band (P < 0.05) compared to controls, but had no significant effect on MHR, MBP, CVP, and RLS. Single-dose i.v. dexamethasone showed a trend to improve gas exchange, however, increased parasympathetic activity, what should be considered in use of corticosteroids in the treatment of meconium aspiration syndrome.

Continuous positive airway pressure and conventional mechanical ventilation in the treatment of meconium aspiration syndrome

Meconium aspiration syndrome (MAS) is a complex syndrome that ranges in severity from mild respiratory distress to severe respiratory failure, persistent pulmonary hypertension of the newborn and sometimes death. Understanding of the syndrome's complicated pathophysiology will help determine the appropriate treatment strategy, including the use of continuous positive airway pressure (CPAP), conventional mechanical ventilation (CMV) and other therapies. Approximately 30 to 50% of infants diagnosed with MAS will require CPAP or mechanical ventilation. The optimum modes of ventilation for MAS are not known. Very few studies have been conducted to determine 'best' ventilatory strategies. Despite the introduction, over the last two decades, of innovative ventilatory treatments for this disease (for example, surfactant, high-frequency ventilation, inhaled nitric oxide, extracorporeal membrane oxygenation), the majority of infants can be successfully managed with CPAP or mechanical ventilation alone.

Treatment of MAS with PPHN using combined therapy: SLL, bolus surfactant and iNO

The objective of the study was to compare the effectiveness of surfactant treatment either by bolus or surfactant lung lavage followed by inhaled nitric oxide (iNO) therapy in infants with meconium aspiration syndrome (MAS) complicated by persistent pulmonary hypertension (PPHN). In this study, thirteen infants with diagnosis of MAS and PPHN were first treated with conventional respiratory support. Then between 2 and 22h of life they were randomized either to bolus surfactant treatment (n=6) or surfactant lung lavage (SLL, n=7) treatment. Then all infants were treated with iNO therapy. The groups were compared with regard to their clinical course: changes in PaO(2), FiO(2), MAP, OI, A-a oxygen gradient, duration of iNO therapy, length of ventilation and hospitalization. Complications and mortality were also compared. The results showed that infants treated with SLL had significant improvements in oxygenation, decreases in MAP and A-a gradients. But there were no significant differences in duration of ventilation, iNO treatment, length of hospitalization or complications. In conclusion these data show no advantage of SLL therapy over bolus surfactant treatment in infants with MAS complicated by PPHN.

Rapid cardiovascular effects of dexamethasone in rabbits with meconium-induced acute lung injury

Glucocorticoids may improve lung function in newborns with meconium aspiration syndrome (MAS), but information on the acute side effects of glucocorticoids in infants is limited. In this study using a rabbit model of MAS, we addressed the hypothesis that systemic administration of dexamethasone causes acute cardiovascular changes. Adult rabbits were treated with 2 intravenous doses of dexamethasone (0.5 mg/kg each) or saline at 0.5 h and 2.5 h after intratracheal instillation of human meconium or saline. Animals were oxygen-ventilated for 5 h after the first dose of treatment. Blood pressure, heart rate, and short-term heart rate variability (HRV) were analyzed during treatment, for 5 min immediately after each dose, and for the 5 h of the experiment. In the meconium-instilled animals, dexamethasone increased blood pressure, decreased heart rate, increased HRV parameters, and caused cardiac arrhythmia during and immediately after administration. In the saline-instilled animals, the effect of dexamethasone was inconsistent. In these animals, the acute effects of dexamethasone on blood pressure and cardiac rhythm were reversed after 30 min, whereas heart rate continued to decrease and HRV parameters continued to increase for 5 h after the first dose of dexamethasone. These effects were more pronounced in meconium-instilled animals. If systemic glucocorticoids are used in the treatment of MAS, cardiovascular side effects of glucocorticoids should be considered.

Refining the Method of Therapeutic Lung Lavage in Meconium Aspiration Syndrome

Background: Therapeutic lung lavage is an emerging treatment for meconium aspiration syndrome (MAS), but the ideal fluid volume and lavage technique remain unclear. Objective: To evaluate the impact of suction technique, chest squeeze and aliquot volume on the efficacy of lung lavage in MAS. Methods: MAS was induced in ventilated 2-week-old piglets using 4 ml/kg of 20% human meconium. Lung lavage with either two 8 ml/kg saline aliquots (n = 5) or a single 15 ml/kg aliquot (n = 6) was performed soon after meconium instillation. Lavage fluid was recovered by three methods performed in sequence: closed suction via a suction adaptor; open suction with the ventilator disconnected, and open suction with manual vibratory chest squeezing. Return fluid was collected separately with each method. Recovery of meconium and lavage fluid was determined and expressed as a proportion of the amount instilled. Results: Closed suction resulted in poor meconium and fluid returns, with recovery of meconium being only 5.2 ± (SD) 2.5% with 2 × 8 ml/kg lavage and 19 ± 11% with a single 15 ml/kg aliquot. Chest squeeze during suction increased recovery of both meconium and lavage fluid. Overall recovery of instilled meconium was greater with 15 ml/kg lavage (45 ± 17%) than with two 8 ml/kg aliquots (24 ± 4.5%, p = 0.028, repeated-measures ANOVA); the corresponding values for return of lavage fluid were 73 ± 10 and 49 ± 13%, respectively (p < 0.01). Conclusions: Open suction, vibratory chest squeezing and an aliquot volume of 15 ml/kg each improve the efficacy of lung lavage in MAS, and merit inclusion in the lavage technique in clinical trials of this therapy.

Bronchoalveolar lavage with pulmonary surfactant/dextran mixture improves meconium clearance and lung functions in experimental meconium aspiration syndrome

Surfactant lung lavage is a promising approach in the treatment of meconium aspiration syndrome (MAS). We hypothesise that the enrichment of modified natural surfactant with dextran will enhance meconium clearance from the airspaces during lung lavage and improve lung function in experimental MAS. Human meconium (30 mg/ml; 4 ml/kg) was instilled into the tracheal cannula of anaesthetised and paralysed adult rabbits to induce respiratory failure. The animals were then lavaged with saline (Sal), surfactant without (Surf) and with dextran (Surf+dex). Lung lavage (10 ml/kg in three portions) was performed with diluted surfactant (Curosurf, 10 mg/ml, 100 mg/kg) without or with dextran (3 mg/mg of surfactant phospholipids) or saline and the animals were conventionally ventilated with 100% O(2) for an additional hour. Lung functions were measured prior to and after meconium instillation, and 10, 30 and 60 min after lavage. The recovery of meconium in bronchoalveolar lavage (BAL) fluid was quantified. More meconium solids was recovered in the surfactant-lavaged than in the saline-lavaged groups (Surf: 12.4 +/- 3.9% and Surf+dex: 17.5 +/- 3.5% vs. Sal: 4.8 +/- 1.0%; both P < 0.01). Moreover, more meconium solids was obtained by Curosurf/dextran than by Curosurf-only lavage (P < 0.05). In the Surf group, the values for PaO(2)/FiO(2) were significantly higher than in the controls (at 60 min: 24.5 +/- 4.2 kPa vs.9.1 +/- 2.2 kPa, P < 0.01). An additional increase in oxygenation was seen in the Surf+dex group (at 60 min: 34.2 +/- 8.1 kPa, P vs. Surf group <0.01). The lung-thorax compliance was higher in the Surf+dex group in comparison with the Sal and Surf groups (at 60 min: 9.6 +/- 0.9 vs.7.6 +/- 1.2, P < 0.01 and 8.0 +/- 0.7 ml/kPa/kg, P < 0.05). The enrichment of Curosurf with dextran improves meconium clearance and lung functions in surfactant-lavaged rabbits with meconium aspiration.