Partial Liquid Ventilation Research Articles

The 2020 Joseph W. St Geme, Jr. Leadership Award Address: On Leadership and the Joy of Pediatrics

The 2020 Joseph W. St Geme, Jr. Leadership Award Address: On Leadership and the Joy of Pediatrics

Paediatrics: how to manage acute respiratory distress syndrome.

BackgroundAcute respiratory distress syndrome (ARDS) is a significant cause of mortality and morbidity amongst critically ill children. The purpose of this narrative review is to provide an up-to-date review on the evaluation and management of paediatric ARDS (PARDS).MethodsA PubMed search was performed with Clinical Queries using the key term “acute respiratory distress syndrome”. The search strategy included clinical trials, meta-analyses, randomized controlled trials, observational studies and reviews. Google, Wikipedia and UpToDate were also searched to enrich the review. The search was restricted to the English literature and children.DiscussionNon-invasive positive pressure ventilation, lung-protective ventilation strategies, conservative fluid management and adequate nutritional support all have proven efficacy in the management of PARDS. The Pediatric Acute Lung Injury Consensus Conference recommends the use of corticosteroids, high-frequency oscillation ventilation and inhaled nitric oxide in selected scenarios. Partial liquid ventilation and surfactant are not considered efficacious based on evidence from clinical trials.ConclusionPARDS is a serious but relatively rare cause of admission into the paediatric intensive care unit and is associated with high mortality. Non-invasive positive pressure ventilation, lung-protective ventilation strategies, conservative fluid management and adequate nutrition are advocated. As there has been a lack of progress in the management of PARDS in recent years, further well-designed, large-scale, randomized controlled trials in this field are urgently needed.

Effect of perfluorocarbon partial liquid ventilation-induced hypothermia on dogs with acute lung injury.

Acute lung injury (ALI) is the damage of alveolar epithelial cells and capillary endothelial cells caused by various direct and indirect injury factors, resulting in diffuse pulmonary interstitial and alveolar edema, resulting in acute hypoxic respiratory insufficiency. This study aimed to investigate the effects of hypothermia induced by partial fluid ventilation on dogs with ALI. The experimental dogs were randomly divided into a conventional mechanical ventilation group (CMV) group, a normal temperature perfluorocarbon liquid ventilation group (NPLV) group, and a hypothermic perfluorocarbon liquid ventilation group (HPLV) group. After induction of ALI, the dogs of the CMV group was treated with CMV for respiratory support, the HPLV group was given a 15 °C low-temperature perfluorocarbon partial liquid ventilation (PLV), and the NPLV group was given partial fluid permeation of perfluorocarbon (PFC) at a room temperature of 37 °C. Anesthesia was stable at 0.5 h (T0), and successful modeling (T1), at 1 h (T2), 2 h (T3), 3 h (T4) and 4 h (T5) was completed. Blood gas analysis was performed, and rectum temperature, peak airway pressure (PIP), and lung compliance were measured. We performed enzyme-linked immunosorbent assay (ELISA) for peripheral blood and postoperative bronchoalveolar lavage fluid (BALF), calculation of lung tissue wet weight/dry weight ratio, and Western blot detection of NF-κB p65. In the HPLV group, the blood gas index of dogs with ALI was close to normal. In T2¬-T5, the rectal temperature of the HPLV group was significantly lower than that of the NPLV group and the CMV group the lung compliance in the HPLV group and the NPLV group was lower than that in the CMV group at the T2-T5 time point, while the CLst value was significantly increased. The detection of peripheral blood and BALF in dogs showed that interleukin-10 (IL-10) was significantly increased and TNF-α was significantly decreased in the HPLV group compared with the CMV group and NPLV group. Compared with CMV group, the wet/dry ratio of lung tissue in the BALF of HPLV group was decreased. The results indicate that mild hypothermia caused by partial fluid ventilation can increase oxygenation capacity, oxygen partial pressure, the expression of anti-inflammatory factor IL-10 and improve lung compliance in dogs with ALI.

Neonatal Partial Liquid Ventilation for the Treatment and Prevention of Bronchopulmonary Dysplasia.

* Abbreviations: ARDS: : acute respiratory distress syndrome BPD: : bronchopulmonary dysplasia CHOP: : Children’s Hospital of Philadelphia ECLS: : extracorporeal life support FDA: : Food and Drug Administration FRC: : functional residual capacity HFOV: : high-frequency oscillatory ventilation PEEP: : positive end-expiratory pressure PFC: : perfluorocarbon PFOB: : perfluorooctyl bromide PLV: : partial liquid ventilation RDS: : respiratory distress syndrome TLV: : total (tidal) liquid ventilation Survival rates in extremely premature infants are increasing as are rates of bronchopulmonary dysplasia. Current therapeutic options are not sufficient to prevent or treat bronchopulmonary dysplasia in many infants. This presents a large cost, both human and economic. Perfluorocarbon liquids have been studied since the 1960s for various biomedical applications. After some promising studies in the 1990s, work in this field was halted. Despite considerable attention, including significant amounts of published data, the temporal gap has seen a generation of physicians who may not know about this potentially valuable therapy. This article will reintroduce partial liquid ventilation, a promising therapeutic option in acute and chronically ill infants, to clinicians by examining the history and presenting new data. After completing this article, readers should be able to: 1. Identify the physiologic function of perfluorocarbon liquid in the human lung. 2. Describe the historical development of partial liquid ventilation and contextualize the published literature. 3. Explain the limitations of partial liquid ventilation and roadblocks in the past. In their 1962 article entitled, “Of mice as fish,” Kylstra and colleagues wrote with excitement about the implications of a newfound mode of ventilation. In liquid ventilation using oxygenated saline solutions, these investigators saw a sort of reverse engineering of evolution—mammals regressing to their supposed piscine origins. Kylstra et al envisioned a world in which pool water, titrated to have an adequate saline concentration, would allow for more efficacious resuscitation from drowning. (1) In its most essential form, liquid ventilation involves filling the lungs of an animal with some kind of liquid. That liquid, at varying doses, may be cycled in and out of the lungs with the assistance of a ventilator. In 1966, Clark and Gollan first described the use of perfluorocarbons (PFCs) in liquid ventilation toward a similar end as did Kylstra and colleagues—undersea survival and …

Pulmonary stretch receptor activity during partial liquid ventilation with different pressure waveforms

BackgroundThe aim of the present study was to investigate pulmonary stretch receptor activity (PSR) under different peak inspiratory pressures (PIPs) and inspiratory pressure waveforms during partial liquid (PLV) and gas ventilation (GV). MethodsPSR instantaneous impulse frequency (PSRfimp) was recorded from single fibers in the vagal nerve during PLV and GV in young cats. PIPs were set at 1.2/1.8/2.2/2.7 kPa, and square and sinusoidal pressure waveforms were applied. ResultsPSRfimp at the start of inspiration increased with increasing PIPs, and was steeper and higher with square than with sinusoidal waveforms (p < 0.05). Total number of impulses, peak and mean PSRfimp were lower during PLV than GV at the lowest and highest PIPs (p < 0.025). Time to peak PSRfimp was shorter with square than with sinusoidal waveforms at all pressures and ventilations (p < 0.005). Irrespective of waveform, lower PIPs yielded lower ventilation during PLV. ConclusionAs assessed by PSRfimp, increased PIPs do not expose the lungs to more stretching during PLV than during GV, with only minor differences between square and sinusoidal waveforms.

Perfluorocarbons: Knowledge Gained From Clinical Trials.

Research into potential use of perfluorocarbons for liquid ventilation and as oxygen delivery agents in humans has been underway since the 1960s. While partial liquid ventilation with perfluorocarbons showed promise in animal models and early human investigation, randomized controlled human trials failed to show benefit and an elevated rate of adverse events. Initial approval of Fluosol-DA (Green Cross Corporation, Osaka, Japan) by the United States Food and Drug Administration as an oxygen delivery agent for use in high-risk coronary angioplasty represents the only approved application of these compounds to supplement tissue oxygenation, but the compound was rendered obsolete and removed from the market with the development of advanced angioplasty catheters in the 1990s. Second-generation perfluorocarbons were developed with a higher capacity to increase the amount of oxygen dissolved in the fluid phase of blood. Early clinical trials of perflubron emulsion in non-cardiac and cardiac surgery were promising, but dose restriction and the requirement for high inspired oxygen concentration to maximize oxygen delivery for prolonged periods of time limited the clinical utility as a replacement for the oxygen carrying capacity of red blood cells. Identification of excess serious adverse events in treated patients resulted in discontinuation of pivotal clinical trials. Continued research investigating different formulations of perfluorocarbons has shown promise in animal studies, but continued research is necessary to prove safety and efficacy in humans.

Partial liquid ventilation–induced mild hypothermia improves the lung function and alleviates the inflammatory response during acute respiratory distress syndrome in canines

Background Acute respiratory distress syndrome (ARDS), which is the severest form of pulmonary injury, is the leading cause of death in critical care. At present, the mortality remains high in ARDS. Partial liquid ventilation (PLV) using perfluorocarbon (PFC) has been proven to improve gas exchange and respiratory dynamics of the lungs during ARDS. However, PLV has not been shown to reduce the mortality of ARDS. Some studies have shown that mild hypothermia therapy can reduce lung injuries in animal models of ARDS by reducing inflammatory cytokine levels in lung tissues. However, hypothermia cannot produce a lung protection effect alone, and it may have a synergistic effect with other protective measures. To explore the possible role of PLV combined with mild hypothermia in the treatment of ARDS, in this study, we used PFC liquid ventilation to induce mild hypothermia in dogs suffering from ARDS and analyzed the effects of PFC liquid ventilation-induced mild hypothermia on the levels of inflammatory factors and lung histopathology in dogs with ARDS. The experimental dogs were randomly divided into conventional mechanical ventilation (CMV), normal temperature PFC liquid ventilation (NPLV), hypothermic PFC liquid ventilation (HPLV), and mechanical ventilation (MV) groups. After induction of ARDS, the CMV group was treated with CMV for respiratory support, the HPLV group was treated with PLV-induced mild hypothermia using 15 °C PFC and maintained the rectal temperature at 34–36 °C, the NPLV group was treated with PLV using 36 °C PFC and maintained the rectal temperature at 36–38 °C. The MV group served as the control group. Analyses of the pulmonary pathology, partial pressure of oxygen in the blood, and lung wet-dry weight ratio (W/T) of each dog revealed that PLV-induced mild hypothermia significantly increased the PaO2 values and attenuated lung injury, and there were no adverse effects on hemodynamics. Furthermore, treatment with PLV-induced mild hypothermia significantly increased the expression of the anti-inflammatory factor IL-10 in bronchoalveolar lavage fluid (BALF) and attenuated the expression of interleukin (IL-6) and tumor necrosis factor-α (TNF-α) in peripheral blood and in lung BALF. Moreover, the results showed that the expression of myeloperoxidase (MPO) and NF-κB p65 in lung tissues was significantly decreased by PLV-induced mild hypothermia compared with NPLV and CMV. Our results indicated that PLV combined with mild hypothermia can provide protection against oleic acid-induced ARDS in dogs.

Pharmacological agents for adults with acute respiratory distress syndrome.

Pharmacological agents for adults with acute respiratory distress syndrome.

Imaging Assessment of Partial Liquid Ventilation in Bronchopulmonary Dysplasia

Partial liquid ventilation is proposed as an alternative ventilation strategy to reduce surface tension, increase alveolar recruitment, and decrease inflammation. Studied in acute respiratory distress and other indications, liquid ventilation is being revisited for infants with bronchopulmonary dysplasia. Perfluorooctyl bromide used for liquid ventilation is radiopaque, allowing radiographic visualization of lung liquid ventilation patterns that may provide additional insight into pulmonary pathophysiology. Current protocols utilize reduced liquid dosing, resulting in unique imaging features. We discuss optimal radiographic technique and report initial ultrasound evaluation results. With renewed interest in partial liquid ventilation, it may be helpful for pediatric radiologists to familiarize themselves with the clinical use and radiographic appearance of liquid ventilation material.

Partial liquid ventilation for bronchopulmonary dysplasia: Visualizing ventilation patterns on chest radiographs

Despite the advances in neonatal intensive care, bronchopulmonary dysplasia (BPD) still remains a major cause of mortality and morbidity in many preterm infants. A definitive treatment still does not exist, and BPD has serious consequences, including poor cardiopulmonary function and development. Hence, to address this need, a randomized clinical trial (NCT03041740) is currently underway to assess the safety and feasibility of partial liquid ventilation (PLV) in preterm infants with severe BPD.

Special mechanical ventilation: heliox ventilation and partial liquid ventilation

Neonatal mortality has been significantly decreased because of the development of neonatal respiratory support techniques.Nevertheless, constant and high frequency ventilators have some limitations to solve all problems in neonatal respiratory failure.Special mechanical ventilation, mainly including heliox and partial liquid ventilation, provides new respiratory support for newborn infants.The clinical significance of heliox and partial liquid ventilation need further investigation. Key words: Heliox; Partial liquid ventilation; Special mechanical ventilation,

High-frequency oscillatory ventilation combined with partial liquid ventilation in experimental lung injury: effects on lung cell apoptosis

SummaryObjectiveTo investigate the effects of high-frequency oscillatory ventilation (HFOV) and partial liquid ventilation (PLV) on apoptosis of lung tissue induced by steam inhalation injury in rabbit.DesignA prospective, randomized, controlled, multiple-group study.SettingAn animal research laboratory centre in a university burns centre.SubjectsNew Zealand rabbits (n = 32; 2.25 ± 0.25 kg) of either sex.InterventionsThe animals were ventilated by HFOV with a mean airway pressure of 10 cm H2O, a frequency of 10 Hz, an amplitude of 20 cm H2O, an inspiratory:expiratory ratio of 1:1, and an FiO2 of 1.0. After the induction of acute lung injury (ALI) by steam inhalation, the animals were randomly divided into four groups: CMV, HFOV, CMV + PLV, HFOV + PLV group. Then they were ventilated for 4 h by CMV, HFOV, CMV + PLV and HFOV + PLV, respectively. After the experimental period, cell apoptosis and apoptosis indexes in the lung tissue were assessed with TUNEL FragELTM (Fragment End Labeling).ResultsLung tissue apoptosis indexes in HFOV group and HFOV + PLV group were lower than that of in CMV group and CMV + PLV group; between-group comparison had significant difference (P < 0.01). HFOV + PLV group showed lowest apoptosis indexes.ConclusionHFOV combined with PLV can suppress lung tissue apoptosis induced by steam inhalation.

Effects on lung stress of position and different doses of perfluorocarbon in a model of ARDS

We determined whether the combination of low dose partial liquid ventilation (PLV) with perfluorocarbons (PFC) and prone positioning improved lung function while inducing minimal stress. Eighteen pigs with acute lung injury were assigned to conventional mechanical ventilation (CMV) or PLV (5 or 10ml/kg of PFC). Positive end-expiratory pressure (PEEP) trials in supine and prone positions were performed. Data were analyzed by a multivariate polynomial regression model. The interplay between PLV and position depended on the PEEP level. In supine PLV dampened the stress induced by increased PEEP during the trial. The PFC dose of 5ml/kg was more effective than the dose 10ml/kg. This effect was not observed in prone. Oxygenation was significantly higher in prone than in supine position mainly at lower levels of PEEP. In conclusion, MV settings should take both gas exchange and stress/strain into account. When protective CMV fails, rescue strategies combining prone positioning and PLV with optimal PEEP should improve gas exchange with minimal stress.

The PulmoSphere™ Platform for Pulmonary Drug Delivery

Spray-dried PulmoSphere™ formulations comprise phospholipid-based small, porous particles. Drug(s) may be incorporated in or with PulmoSphere formulations in three formats: solution-, suspension-, and carrier-based systems. The multiple formats may be administered to the respiratory tract with multiple delivery systems, including portable inhalers (pressurized, metered-dose inhaler and dry-powder inhaler), nebulizers, and via liquid dose instillation in conjunction with partial liquid ventilation. The PulmoSphere platform (particles, formats, delivery systems) enables pulmonary delivery of a broad range of drugs independent of their physicochemical properties and lung dose. The engineered particles provide significant improvements in lung targeting and dose consistency, relative to current marketed inhalers.

The effect of partial liquid ventilation on inflammatory response in piglets with acute lung injury induced by lipopolysaccharide

To evaluate the effect of partial liquid ventilation (PLV) on pro-inflammatory and anti-inflammatory factors change in lipopolysaccharide (LPS)-induced piglets acute lung injury (ALI). Twelve Shanghai white piglets were randomly divided into mechanical ventilation (MV) group (n=6) and PLV group (n=6). 60 μg×kg(-1)×h(-1) LPS were intravenous infused continuously for 2 hours to induce ALI model. PLV model was set on the basis of the MV by endotracheal injection of perfluorodecalin (PFC, 10 mL/kg). The hemodynamic and respiratory parameters such as mechanics and arterial blood gas analysis were monitored at basic condition and after lung injury establishment (0, 1, 2, 4 hours). The serum levels of interleukin (IL-1β, IL-6, IL-8, IL-10) and tumor necrosis factor-α (TNF-α) were dynamically monitored by enzyme linked immunosorbent assay (ELISA). A lung injury score was used to quantify lung tissues change under light microscopic observations. Ventilation and oxygenation function were improved gradually after PFC endotracheal injection in PLV group, and there were significant difference compared with MV group at 4 hours [heart rate (HR): 144 ± 6 beats/min vs. 179 ± 9 beats/min, respiratory rate (RR): 58 ± 4 beats/min vs. 77 ± 6 beats/min, mean arterial blood pressure (MAP): 99 ± 7 mmHg vs. 75 ± 29 mmHg, dynamic lung compliance (Cdyn): 1.9 ± 0.3 mL×cmH(2)O(-1)×kg(-1) vs. 1.2 ± 0.4 mL×cmH(2)O(-1)×kg(-1), tidal volume (VT): 7.8 ± 0.4 mL/kg vs. 5.8 ± 0.9 mL/kg, mean airway resistance (Raw): 20.5 ± 6.6 cmH(2)O×L(-1)×s(-1) vs. 35.2 ± 4.0 cmH(2)O×L(-1)×s(-1), mean airway pressure (Paw): 1.0 ± 0.5 cmH(2)O vs. 3.0 ± 0.9 cmH(2)O, ventilation efficacy index (VEI): 0.18 ± 0.02 vs. 0.08 ± 0.02, pH value: 7.386 ± 0.143 vs. 7.148 ± 0.165, arterial partial pressure of oxygen (PaO(2)): 121.8 ± 12.5 mmHg vs. 73.6 ± 10.9 mmHg, arterial partial pressure of carbon dioxide (PaCO(2)): 39.6 ± 20.3 mmHg vs. 66.8 ± 23.5 mmHg, oxygenation index (PaO(2)/FiO(2)): 311 ± 35 mmHg vs. 184 ± 27 mmHg, P<0.05 or P<0.01]. All serum cytokines in both groups were significantly increased after LPS-induced ALI, and showed an elevated tendency. The serum pro-inflammatory factors of TNF-α, IL-1β, IL-6 and IL-8 in PLV group were significantly lower than those in MV group at 4 hours (TNF-α: 98.4 ± 21.1 ng/L vs. 178.0 ± 55.0 ng/L, IL-1β: 142.0 ± 38.0 ng/L vs. 226.0 ± 55.0 ng/L, IL-6: 763.0 ± 282.0 ng/L vs. 1 303.0 ± 260.0 ng/L, IL-8: 1 183.0 ± 403.0 ng/L vs. 1 876.0 ± 232.0 ng/L, P<0.05 or P<0.01). There was no significant difference in serum anti-inflammatory factor of IL-10 between PLV and MV groups at 4 hours (292.0 ± 40.0 ng/L vs. 208.0 ± 82.0 ng/L, P>0.05). The ratio of TNF-α/IL-10 in PLV group was significantly decreased compared with MV group at 2 hours (0.58 ± 0.13 vs. 1.13 ± 0.54, P<0.05). The ratio of IL-6/IL-10 in PLV group was significantly decreased compared with MV group at 4 hours (2.72 ± 1.27 vs. 7.17 ± 3.08, P<0.01). Microscopic changes in intra-alveolar and interstitial inflammation, hemorrhage and edema were better in PLV group than those in MV group. The lung injury score of PLV group was lower than MV group (independent lung regions: 9.8 ± 0.8 vs. 11.8 ± 1.0, t=3.956, P=0.003; dependent lung regions: 5.0 ± 0.6 vs. 14.7 ± 2.3, t=10.127, P=0.000). PLV can significantly reduce the levels of pro-inflammatory factors and the ratio of pro-inflammatory/anti-inflammatory factor, which may contribute to the protective effects of PLV on ALI.

Liquid ventilation.

Human have lungs to breathe air and they have no gills to breath liquids like fish. When the surface tension at the air-liquid interface of the lung increases as in acute lung injury, scientists started to think about filling the lung with fluid instead of air to reduce the surface tension and facilitate ventilation. Liquid ventilation (LV) is a technique of mechanical ventilation in which the lungs are insufflated with an oxygenated perfluorochemical liquid rather than an oxygen-containing gas mixture. The use of perfluorochemicals, rather than nitrogen as the inert carrier of oxygen and carbon dioxide offers a number of advantages for the treatment of acute lung injury. In addition, there are non-respiratory applications with expanding potential including pulmonary drug delivery and radiographic imaging. It is well-known that respiratory diseases are one of the most common causes of morbidity and mortality in intensive care unit. During the past few years several new modalities of treatment have been introduced. One of them and probably the most fascinating, is of LV. Partial LV, on which much of the existing research has concentrated, requires partial filling of lungs with perfluorocarbons (PFC's) and ventilation with gas tidal volumes using conventional mechanical ventilators. Various physico-chemical properties of PFC's make them the ideal media. It results in a dramatic improvement in lung compliance and oxygenation and decline in mean airway pressure and oxygen requirements. No long-term side-effect reported.

Effect of partial liquid ventilation on lung function in oleic acidinduced lung injury model of piglets

Background Pediatric patients are susceptible to lung injury that does not respond to traditional therapies. Partial liquid ventilation (PLV) has been developed as an alternative ventilatory strategy for treating severe lung injury. The aim of this study is to investigate the effect of PLV on lung function in immature piglets. Methods Acute lung injury was induced in 12 Chinese immature piglets by oleic acid (OA). The animals were randomly assigned to two groups (n=6 each group): (1) conventional mechanical ventilation (MV) group and (2) PLV with FC-77 (10 ml/kg) group. Mean arterial blood pressure (MAP), mean pulmonary arterial pressure (MPAP), central venous pressure (CVP), left atrial pressure (LAP), systemic vascular resistance (SVR), pulmonary vascular resistance (PVR), cardiac output (CO), mean pressure of airway (Paw), dynamic lung compliance (Cydn), and arterial blood gases were measured during the observation period. Results No piglet died in either group with severe lung injury. After four hours of ventilation, pH in the MV group gradually decreased to lower than 7.20, while in the PLV group, pH also gradually decreased but remained higher than 7.20 (P &lt;0.05). Partial pressure of oxygen in artery (PaO2) decreased in both groups, but with a significant difference between the PLV group and MV group (P &lt;0.05). Partial pressure of carbon dioxide in artery (PaCO2) increased in both groups, but with a significant difference between the PLV group and MV group (P &lt;0.05). Paw increased in both groups, but was not significantly different (P &gt;0.05). Cydn decreased in both groups, but without a significant difference (P &gt;0.05). At four hours, heart rate (HR) and MAP in both groups decreased. MPAP in both groups increased, and there was a significant difference between the two groups (P &lt;0.05). CVP was stable in both groups. At four hours, PVR and LAP were increased in both groups. CO was decreased in both groups (P &lt;0.05). SVR was stable during the observation time. Conclusion PLV did not improve outcome in changes of lung function.

Protective effect of partial liquid ventilation on non-heart-beating-donor lung

Objective To investigate the protection of non-heart-beating-donor lung with part liquid ventilation.Methods Thirty-six health SD rats were randomly divided into three groups,n =12:oxygen group (group C),salt water group (group B),and part liquid ventilation group (group A).Mechanical ventilation was done for 2 h after establishment of non-heart-beating donor lung model,and airway pressure was measured continuously during 2 h.After 2 h,P-V curve was measured.Resection the under leaves of the rats,observe the different pathological characteristics by electron microscopy of the lung.Right lung was taking irrigation,measurement of bronchial lung lavaged suffactant protein B,C (SP-B,the SP-C) concentrations.Cut the upper lobe toward the right lung and measurement SP-B and SP-C with real-time quantitative polymerase chain reaction (Real-time PCR) testing.Results The dynamic compliance and static compliance of group A are better than group B and C during 2 hours hot ischemia(P ＜0.05) ;Pathology organization score of group A is better than group B and C (P ＜ 0.05) ; SP-B and SP-C enzyme linked immunosorbent assay (ELISA) test and lung tissue of the Real-time PCR testing instructions protein and RNA content are difference,group A is higher than group B and C (P ＜ 0.05).Conclusion Part liquid ventilation protect pulmonary lung function and lung tissue well during heat during ischemia,and have very good protection effect to the SP-B and SP-C. Key words: Perfluorocarbon; Liquid ventilation; Non-heart-beating donor; Protection during warm ischemia

A comparison of conventional surfactant treatment and partial liquid ventilation on the lung volume of injured ventilated small lungs

As an alternative to surfactant therapy (ST), partial liquid ventilation (PLV) with perfluorocarbons (PFC) has been considered as a treatment for acute lung injury (ALI) in newborns. The instilled PFC is much heavier than the instilled surfactant and the aim of this study was to investigate whether PLV, compared to ST, increases the end-expiratory volume of the lung (VL). Fifteen newborn piglets (age <12 h, mean weight 678 g) underwent saline lung lavage to achieve a surfactant depletion. Thereafter animals were randomized to PLV (n = 8), receiving PFC PF5080 (3M, Germany) at 30 mL kg−1, and ST (n = 7) receiving 120 mg Curosurf®. Blood gases, hemodynamics and static compliance were measured initially (baseline), immediately after ALI, and after 240 min mechanical ventilation with either technique. Subsequently all piglets were killed; the lungs were removed in toto and frozen in liquid N2. After freeze-drying the lungs were cut into lung cubes (LCs) with edge lengths of 0.7 cm, to calculate VL. All LCs were weighed and the density of the dried lung tissue was calculated. No statistically significant differences between treatment groups PLV and ST (means ± SD) were noted in body weight (676 ± 16 g versus 679 ± 17 g; P = 0.974) or lung dry weight (1.64 ± 0.29 g versus 1.79 ± 0.48 g; P = 0.48). Oxygenation index and ventilatory efficacy index did not differ significantly between both groups at any time. VL (34.28 ± 6.13 mL versus 26.22 ± 8.1 mL; P < 0.05) and the density of the dried lung tissue (48.07 ± 5.02 mg mL−1 versus 69.07 ± 5.30 mg mL−1; P < 0.001), however, differed significantly between the PLV and ST groups. A 4 h PLV treatment of injured ventilated small lungs increased VL by 30% and decreased lung density by 31% compared to ST treatment, indicating greater lung distension after PLV compared to ST.

Partial liquid ventilation for preventing death and morbidity in adults with acute lung injury and acute respiratory distress syndrome

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are syndromes of severe respiratory failure that are associated with substantial mortality and morbidity. Artifical ventilatory support is commonly required and may exacerbate lung injury. Partial liquid ventilation (PLV) has been proposed as a less injurious form of ventilatory support for these patients. Although PLV has been shown to improve gas exchange and to reduce inflammation in experimental models of ALI, a previous systematic review did not find any evidence to support or refute its use in humans with ALI and ARDS. The primary objective of this review was to assess whether PLV reduced mortality (at 28 d, at discharge from the intensive care unit (ICU), at discharge from hospital and at one, two and five years) in adults with ALI or ARDS when compared with conventional ventilatory support.Secondary objectives were to determine how PLV compared with conventional ventilation with regard to duration of invasive mechanical ventilation, duration of respiratory support, duration of oxygen therapy, length of ICU stay, length of hospital stay, incidence of infection, long-term cognitive impairment, long-term health related quality of life, long- term lung function, long-term morbidity costs and adverse events. The following adverse events were considered: hypoxia (arterial PO2 <80 mm Hg), pneumothorax (any air leak into the pleural space requiring therapeutic intervention), hypotension (systolic blood pressure < 90 mm Hg sustained for longer than two minutes or requiring treatment with fluids or vasoactive drugs), bradycardia (heart rate < 50 beats per minute sustained for longer than one minute or requiring therapeutic intervention) and cardiac arrest (absence of effective cardiac output). In this updated review, we searched the Cochrane Central Register of Controlled Trials (CENTRAL Issue 10, 2012, in The Cochrane Library; MEDLINE (Ovid SP, 1966 to November 2012); EMBASE (Ovid SP, 1980 to November 2012) and CINAHL (EBSCOhost,1982 to November 2012) for published studies. In our original review, we searched until May 2004.Grey literature was identified by searching conference proceedings and trial registries and by contacting experts in the field. As in the original review, review authors selected randomized controlled trials that compared PLV with other forms of ventilation in adults (16 y of age or older) with ALI or ARDS, reporting one or more of the following: mortality; duration of mechanical ventilation, respiratory support, oxygen therapy, stay in the intensive care unit or stay in hospital; infection; long-term cognitive impairment or health-related quality of life; long-term lung function or cost. Two review authors independently evaluated the quality of the relevant studies and extracted the data from included studies. In this updated review, one new eligible study was identified and included, yielding a total of two eligible studies (including a combined total of 401 participants). Of those 401 participants, 170 received 'high'-dose partial liquid ventilation (i.e. a mean dose of at least 20 mL/kg), 99 received 'low-dose' partial liquid ventilation (i.e. a dose of 10 mL/kg) and 132 received conventional mechanical ventilation (CMV). Pooled estimates of effect were calculated for all those who received 'high'-dose PLV versus conventional ventilation. No evidence indicated that 'high'-dose PLV either reduced mortality at 28 d (risk ratio (RR) 1.21, 95% confidence interval (CI) 0.79 to 1.85, P = 0.37) or increased the number of days free of CMV at 28 d (mean difference (MD) -2.24, 95% CI -4.71 to 0.23, P = 0.08). The pooled estimate of effect for bradycardia in those who received PLV was significantly greater than in those who received CMV (RR 2.51, 95% CI 1.31 to 4.81, P = 0.005). Pooled estimates of effect for the following adverse events- hypoxia, pneumothorax, hypotension and cardiac arrest- all showed a nonsignificant trend towards a higher occurrence of these events in those treated with PLV. Because neither eligible study addressed morbidity or mortality beyond 28 d, it was not possible to determine the effect of PLV on these outcomes. No evidence supports the use of PLV in ALI or ARDS; some evidence suggests an increased risk of adverse events associated with its use.