This study aimed to establish an animal model of decompression-induced lung injury (DILI) secondary to repetitive diving in mice and explore the role of macrophages in DILI and the protective effects of high-concentration hydrogen (HCH) on DILI. Mice were divided into three groups: control group, DILI group, and HCH group. Mice were exposed to hyperbaric air at 600 kPa for 60 min once daily for consecutive 3 d and then experienced decompression. In HCH group, mice were administered with HCH (66.7% hydrogen and 33.3% oxygen) for 60 min after each hyperbaric exposure. Pulmonary function tests were done 6 h after decompression; the blood was harvested for cell counting; the lung tissues were harvested for the detection of inflammatory cytokines, hematoxylin and eosin (HE) staining, and immunohistochemistry; western blotting and polymerase chain reaction (PCR) were done for the detection of markers for M1 and M2 macrophages. Our results showed that bubbles formed after decompression and repeated hyperbaric exposures significantly reduced the total lung volume and functional residual volume. Moreover, repetitive diving dramatically increased proinflammatory factors and increased the markers of both M1 and M2 macrophages. HCH inhalation improved lung function to a certain extent, and significantly reduced the pro-inflammatory factors. These effects were related to the reduction of M1 macrophages as well as the increase in M2 macrophages. This study indicates that repetitive diving damages lung function and activates lung macrophages, resulting in lung inflammation. HCH inhalation after each diving may be a promising strategy for the prevention of DILI.
Animals ; Cell Polarity ; Diving/adverse effects* ; Lung/physiology* ; Lung Injury/etiology* ; Macrophages/physiology* ; Male ; Mice ; Mice, Inbred BALB C ; Pulmonary Edema/etiology*

OBJECTIVETo appraise the significance of extravascular lung water index (EVLWI), pulmonary vascular permeability index (PVPI), and intrathoracic blood volume index (ITBVI) in the differential diagnosis of the type of burn-induced pulmonary edema.

METHODSThe clinical data of 38 patients, with severe burn hospitalized in our burn ICU from December 2011 to September 2014 suffering from the complication of pulmonary edema within one week post burn and treated with mechanical ventilation accompanied by pulse contour cardiac output monitoring, were retrospectively analyzed. The patients were divided into lung injury group ( L, n = 17) and hydrostatic group (H, n = 21) according to the diagnosis of pulmonary edema. EVLWI, PVPI, ITBVI, oxygenation index, and lung injury score ( LIS) were compared between two groups, and the correlations among the former four indexes and the correlations between each of the former three indexes and types of pulmonary edema were analyzed. Data were processed with t test, chi-square test, Mann-Whitney U test, Pearson correlation test, and accuracy test [receiver operating characteristic (ROC) curve].

RESULTSThere was no statistically significant difference in EVLWI between group L and group H, respectively (12.9 ± 3.1) and (12.1 ± 2.1) mL/kg, U = 159.5, P > 0.05. The PVPI and LIS of patients in group L were respectively 2.6 ± 0.5 and (2.1 ± 0.6) points, and they were significantly higher than those in group H [1.4 ± 0.3 and (1.0 ± 0.6) points, with U values respectively 4.5 and 36.5, P values below 0.01]. The ITBVI and oxygenation index of patients in group L were respectively (911 197) mL/m2 and (136 ± 69) mmHg (1 mmHg = 0.133 kPa), which were significantly lower than those in group H [(1,305 ± 168) mL/m2 and (212 ± 60) mmHg, with U values respectively 21.5 and 70.5, P values below 0.01]. In group L, there was obviously positive correlation between EVLWI and PVPI, or EVLWI and ITBVI (with r values respectively 0.553 and 0.807, P < 0.05 or P < 0.01), and there was obviously negative correlation between oxygenation index and EVLWI, or oxygenation index and PVPI (with r values respectively -0.674 and -0.817, P values below 0.01). In group H, there was obviously positive correlation between EVLWI and ITBVI (r = 0.751, P < 0.01) but no obvious correlation between EVLWI and PVPI, oxygenation index and EVLWI, or oxygenation index and PVPI (with r values respectively -0.275, 0.197, and 0:062, P values above 0.05). The total area under ROC curve of PVPI value for differentiating the type of pulmonary edema was 0.987 [with 95% confidence interval (CI) 0.962-1.013, P < 0.01], and 1.9 was the cutoff value with sensitivity of 94.1% and specificity of 95.2% . The total area under ROC curve of ITBVI value for differentiating the type of pulmonary edema was 0.940 (with 95% CI 0.860-1.020, P < 0.01), and 1,077. 5 mL/m2 was the cutoff value with sensitivity of 95.2% and specificity of 88.2%.

CONCLUSIONSEVLWI, PVPI, and ITBVI have an important significance in the differential diagnosis of the type of burn-induced pulmonary edema, and they may be helpful in the early diagnosis and management of burn-induced pulmonary edema.

Blood Gas Analysis ; Blood Volume ; Burns ; complications ; Capillary Permeability ; Diagnosis, Differential ; Extravascular Lung Water ; Humans ; Lung ; blood supply ; Lung Injury ; physiopathology ; therapy ; Monitoring, Physiologic ; Pulmonary Edema ; diagnosis ; etiology ; ROC Curve ; Respiration, Artificial ; Retrospective Studies

Pulmonary edema frequently occurs after severe burn. It not only impairs pulmonary function directly, but also can induce or exacerbate other pulmonary complications such as lung infection, acute lung injury ( ALI), and ARDS. Extravascular lung water (EVLW) is closely related to the pulmonary edema. Dynamical monitor of EVLW has been used to predict and quantify the degree of pulmonary edema clinically. This review focuses on the recent progresses at home and abroad on the formation mechanism, monitoring approach, and prevention and treatment of EVLW after severe burn injury.
Acute Lung Injury ; etiology ; physiopathology ; Burns ; Extravascular Lung Water ; Humans ; Pulmonary Edema ; diagnosis ; etiology ; Severity of Illness Index ; Shock, Septic ; complications ; physiopathology ; Thermodilution ; Trauma Severity Indices

OBJECTIVETo observe and study the effects of sivelestat on acute lung injury in dogs with severe burn-blast combined injury.

METHODSThirty-two male beagle dogs of clean grade were divided into 4 groups: uninjured group (U), combined injury control group (CIC), combined injury+low dose of sivelestat group (CI+LS), combined injury+high dose of sivelestat group (CI+HS), with 8 dogs in each group. Except for the dogs in group U which were not injured, the dogs in the other 3 groups were inflicted with severe burn-blast combined injury. According to the Parkland formula, the dogs in groups U and CIC were infused with physiological saline, and the dogs in groups CI+LS and CI+HS received sivelestat with the dosage of 0.5 and 2.0 mg·kg(-1)·h(-1) respectively in addition. The 24 h continuous intravenous infusion was carried out for 2 days. At post injury hour (PIH) 6, CT scanning was conducted to observe the lung damage. At PIH 2, 6, 12, 24, and 48, mean arterial pressure (MAP), respiratory rate (RR), extra vascular lung water (EVLW), pulmonary vascular permeability index (PVPI), PaO2, and PaCO2 were measured; the contents of neutrophil elastase (NE), IL-8, and TNF-α were determined by ELISA. At PIH 48, all the dogs were sacrificed, and the lung tissues were harvested to measure the wet to dry lung weight ratio. The same examination was carried out in the dogs of the group U at the same time points. Data were processed with analysis of variance of repeated measurement and LSD test.

RESULTS(1) CT images showed some exudative lesions in the dogs of groups CIC and CI+LS but not in the dogs of groups U and CI+HS. (2) No statistically significant differences were observed in MAP at each time point between every two groups (with P values above 0.05). The RR values in group U were significantly different from those of the other 3 groups at all time points (with P values below 0.05). The values of EVLW and PVPI in 3 combined injury groups were significantly different from those in group U at PIH 6, 12, 24, and 48 (with P values below 0.05). The values of RR and EVLW in group CI+LS were significantly different from those in group CI+HS at PIH 12, 24, and 48 (with P values below 0.05). The values of PVPI in group CI+LS were significantly different from those in group CI+HS at PIH 24 and 48 (with P values below 0.05). (3) The levels of PaO2 and PaCO2 showed significant differences between group U and the other 3 groups at each time point (with P values below 0.05). The levels of PaO2 in group CI+LS were significantly different from those in CI+HS group at PIH 12, 24, and 48 (with P values below 0.05). The level of PaCO2 showed significant differences between group CI+LS and group CI+HS at PIH 24 and 48 (with P values below 0.05). (4) The contents of NE (except for PIH 2), TNF-α, and IL-8 showed significant differences between group U and the other 3 groups at each time point (P < 0.05 or P < 0.01). At PIH 2, 6, 12, 24, and 48, the contents of NE in groups U, CIC, CI+LS, and CI+HS were respectively (69 ± 21), (83 ± 24), (80 ± 20), (75 ± 17), (72 ± 27) pg/mL; (66 ± 24), (196 ± 20), (231 ± 26), (252 ± 25), (266 ± 22) pg/mL ; (71 ± 22), (180 ± 27), (214 ± 21), (194 ± 24), (218 ± 20) pg/mL; (68 ± 22), (136 ± 24), (153 ± 22), (146 ± 26), (150 ± 28) pg/mL. NE values in group CI+HS were statistically different from those in groups CIC and CI+LS at PIH 6, 12, 24, and 48 (with P values below 0.05). The contents of TNF-α in group CI+LS were statistically different from those in groups CIC and CI+HS at PIH 24 and 48 (with P values below 0.05). The contents of IL-8 in group CI+LS were statistically different from those in group CI+HS at PIH 24 and 48 (with P values below 0.05). (5) At PIH 48, the wet to dry lung weight ratio of group CIC was statistically different from that in group CI+LS or group CI+HS (with P values below 0.05); there was also difference between group CI+LS and group CI+HS (P < 0.05).

CONCLUSIONSSivelestat, especially in a high dose, exerts a protective effect in acute lung injury after burn-blast combined injury through improving the index of blood gas analysis, ameliorating pulmonary edema, and lowering the production of pro-inflammatory mediators.

Acute Lung Injury ; complications ; drug therapy ; Animals ; Blood Gas Analysis ; Burns ; complications ; Capillary Permeability ; Dogs ; Extravascular Lung Water ; Glycine ; administration & dosage ; analogs & derivatives ; Infusions, Intravenous ; Interleukin-8 ; Male ; Pulmonary Edema ; etiology ; Serine Proteinase Inhibitors ; administration & dosage ; Sulfonamides ; administration & dosage ; Tumor Necrosis Factor-alpha

OBJECTIVETo analyze the clinical characteristics of negative pressure pulmonary edema (NPPE).

METHODA retrospective investigation of the clinical manifestation, imageology, clinical course and outcome of 4 children with NPPE seen between June 2012 and July 2013 in a children's hospital. The causation of the airway obstruction was also explored.

RESULTAll the 4 cases were boys, the range of age was 40 days to 9 years. They had no history of respiratory and circulatory system disease. In 3 cases the disease had a sudden onset after the obstruction of airway, and in one the onset occurred 1.5 hours after removing the airway foreign body. All these cases presented with tachypnea, dyspnea, and cyanosis, none had fever. Three cases had coarse rales. Chest radiography was performed in 3 cases and CT scan was performed in 1 case, in all of them both lungs displayed diffuse ground-glass-like change and patchy consolidative infiltrates. Three cases were admitted to the ICU, duration of mechanical ventilation was less than 24 hours in 2 cases and 39 hours in one. Oxygen was given by mask to the remaining one in emergency department, whose symptoms were obviously improved in 10 hours. None was treated with diuretics, glucocorticoids or inotropic agents. Chest radiographs were taken within 24 hours of treatment in 2 cases and 24-48 hours in the other 2; almost all the pulmonary infiltrates were resolved. All the 4 cases were cured. The causes of airway obstruction were airway foreign bodies in two cases, laryngospasm in one and laryngomalacia in the other.

CONCLUSIONNPPE is a life-threatening emergency, which is manifested by rapid onset of respiratory distress rapidly (usually in several minutes, but might be hours later) after relief of the airway obstruction, with findings of pulmonary edema in chest radiograph. The symptoms resolve rapidly by oxygen therapy timely with or without mechanical ventilation. In children with airway obstruction, NPPE should be considered.

Acute Disease ; Airway Obstruction ; complications ; Child ; Child, Preschool ; Foreign Bodies ; complications ; Humans ; Infant ; Intensive Care Units ; Intubation, Intratracheal ; methods ; Laryngismus ; complications ; Larynx ; Lung ; diagnostic imaging ; pathology ; Male ; Oxygen Inhalation Therapy ; Positive-Pressure Respiration ; methods ; Pulmonary Edema ; diagnosis ; etiology ; therapy ; Radiography, Thoracic ; Retrospective Studies ; Tomography, X-Ray Computed

OBJECTIVETo investigate the clinical characteristics and treatment of negative pressure pulmonary edema (NPPE) with upper airway obstruction (UAO) in children.

METHODData of 3 cases with NPPE and UAO in pediatric intensive care unit (PICU) from Mar, 2007 to May, 2013 were analyzed.

RESULT(1) Two cases were male and 1 was female with age respectively 6, 16 and 30 months.One had airway foreign body , 1 laryngitis , and 1 retropharyngeal abscess. The onset of NPPE varied from 5 to 40 minutes following relief of obstruction. (2) NPPE presented with acute respiratory distress with signs of tachypnea, tachycardia, 2 of the 3 with pink frothy pulmonary secretions, progressively decreased oxygen saturation, rales on chest auscultation and wheezing. (3) NPPE chest radiograph showed diffuse interstitial and alveolar infiltrates, images confirmed pulmonary edema. (4) All these patients received these therapeutic measures including mechanical ventilation, retaining high PEEP, diuretics, limiting the fluid input volume to 80-90 ml/ (kg×d) on the basis of circulation stability. The rales on chest auscultation disappeared after 10, 6, 12 hours. The ventilators of 2 patients were removed within 24 hours, in another case it was removed 50 hours later because of secondary infection. All patients were cured and discharged without complication.

CONCLUSIONNPPE progresses very fast, characterized by rapid onset of symptoms of respiratory distress after UAO, with pulmonary edema on chest radiograph. The symptoms resolve rapidly if early support of breath and diuretics are applied properly.

Acute Disease ; Airway Obstruction ; complications ; Child, Preschool ; Diuretics ; therapeutic use ; Female ; Foreign Bodies ; complications ; Humans ; Infant ; Laryngismus ; complications ; Male ; Positive-Pressure Respiration ; Postoperative Complications ; etiology ; physiopathology ; therapy ; Pulmonary Edema ; diagnosis ; etiology ; physiopathology ; therapy ; Radiography, Thoracic ; Retrospective Studies

Brain Infarction ; diagnosis ; etiology ; therapy ; Cerebral Angiography ; Child ; Echocardiography, Doppler, Color ; Heart Atria ; Heart Neoplasms ; complications ; diagnosis ; surgery ; Humans ; Intracranial Embolism ; diagnosis ; etiology ; therapy ; Male ; Myxoma ; complications ; diagnosis ; surgery ; Pulmonary Edema ; diagnosis ; etiology ; therapy ; Thrombosis ; diagnosis ; etiology ; therapy

OBJECTIVETo observe and compare the effects of natural colloid and artificial colloid on pulmonary edema of swine during shock stage of severe burn injury.

METHODSTwelve Guangxi Bama miniature swine were inflicted with 40% TBSA full-thickness burn on the back, and then they were divided into natural colloid group (N) and artificial colloid group (A) according to the random number table, with six swine in each group. At post injury hour (PIH) 2, fluid resuscitation was begun. The main part of electrolyte was lactic acid Ringer's solution. The colloids included swine plasma and hydroxyethyl starch 130/0.4. Before injury and at every hour within PIH 48, heart rate, blood pressure, urine volume, central venous pressure (CVP), and pulmonary arterial wedge pressure (PAWP) were recorded. The mean heart rate, blood pressure, urine volume per hour per kg of body weight, CVP, PAWP, resuscitation liquid volume, and the ratio of fluid intake to output during the first and second PIH 24 were calculated. At PIH 48, lung tissue was harvested for histopathological observation and calculation of lung water ratio. Data were processed with one-way analysis of variance, analysis of variance of repeated measurement, LSD test and independent sample t test.

RESULTS(1) There were no statistically significant differences between two groups in heart rate, blood pressure, and urine volume before injury and during the first and second PIH 24 (P values all above 0.05); during the first PIH 24, the CVP and PAWP of group A were significantly higher than those of group N (P values all below 0.05). Compared with those before injury, the heart rate, CVP and PAWP of two groups during the first and second PIH 24 were significantly higher (P < 0.05 or P < 0.01); the urine volume of group N was decreased during the first PIH 24 (P < 0.05), while there was no significant change in group A (P > 0.05); the urine volumes of two groups during the second PIH 24 were increased, while no statistically significant differences were observed (P values all above 0.05). There were no statistically significant differences in blood pressure of two groups between the first, second PIH 24 and before injury (P values all above 0.05). (2) There were no statistically significant differences in the resuscitation liquid volume and fluid intake to output ratio between two groups during the first and second PIH 24 (P values all above 0.05). (3) The alveolar septum was found widened in varying degrees, and there were edema fluid accumulating and inflammatory cell infiltrating within the pulmonary interstitial of lung tissue sections in both two groups. (4) The lung water ratio of group N [(71 ± 10)%] was not statistically significant different from that of group A [(79 ± 4)%, t = -1.753, P > 0.05].

CONCLUSIONSThe natural colloid or artificial colloid (hydroxyethyl starch 130/0.4) applied during shock stage had similar effects on pulmonary edema in swine with severe burn.

Animals ; Burns ; complications ; Disease Models, Animal ; Fluid Therapy ; methods ; Pulmonary Edema ; etiology ; Shock ; complications ; therapy ; Swine

PURPOSE: Several risk factors for development of reexpansion pulmonary edema (REPE) after drainage of pneumothoraces have been reported, but the association between the method of thoracostomy and the development of REPE is unknown. The aim of this study was to compare the frequency of REPE after treatment of spontaneous pneumothorax with trocar or hemostat assisted closed thoracostomy. MATERIALS AND METHODS: We performed a prospective, observational study including 173 patients with spontaneous pneumothorax who visited the emergency department from January 2007 to December 2008. In 2007, patients were treated with hemostat-assisted drainage, whereas patients in 2008 were treated with trocar-assisted drainage. The main outcome was the development of REPE, determined by computed tomography of the chest 8 hours after closed thoracostomy. Outcomes in both groups were compared using univariate and multivariate analyses. RESULTS: Ninety-two patients were included, 48 (42 males) of which underwent hemostat-assisted drainage and 44 (41 males) underwent trocar-assisted drainage. The groups were similar in mean age (24+/-10 vs. 26+/-14 respectively). The frequencies of REPE after hemostat- and trocar-assisted drainage were 63% (30 patients) and 86% (38 patients) respectively (p=0.009). In multivariate analysis, trocar-assisted drainage was the major contributing factor for developing REPE (odds ratio=5.7, 95% confidence interval, 1.5-21). Age, gender, size of pneumothorax, symptom duration and laboratory results were similar between the groups. CONCLUSION: Closed thoracostomy using a trocar is associated with an increased risk of REPE compared with hemostat-assisted drainage in patients with spontaneous pneumothorax.
Adult ; Female ; Hemostatic Techniques ; Humans ; Male ; Multivariate Analysis ; Pneumothorax/*complications/*surgery ; Prospective Studies ; Pulmonary Edema/*diagnosis/etiology/*surgery ; Risk Factors ; Surgical Instruments ; Thoracostomy/*adverse effects/*methods ; Tomography, X-Ray Computed ; Treatment Outcome ; Young Adult

Occurrence of dynamic left ventricular outflow tract (LVOT) obstruction is not infrequent in critically ill patients, and it is associated with potential danger. Here, we report a case of transient heart failure with hemodynamic deterioration paradoxically induced by extreme dehydration. This article describes clinical features of the patient and echocardiographic findings of dynamic LVOT obstruction and significant mitral regurgitation caused by systolic anterior motion of the mitral valve in a volume-depleted heart.
Cardiac Volume ; Dehydration/*complications ; Echocardiography/methods ; Female ; Heart Failure/*etiology/therapy ; Humans ; Middle Aged ; Mitral Valve Insufficiency/complications/*etiology ; Pulmonary Edema/etiology ; Ventricular Outflow Obstruction/*complications/etiology