Acute Respiratory Distress Syndrome Caused by Occupational Exposure to Waterproofing Spray: A Case Report and Literature Review.

Background: Acute respiratory distress syndrome (ARDS) is a serious respiratory disease, caused by severe infection, trauma, shock, inhalation of harmful gases and poisons and presented with acute-onset and high mortality. Timely and accurate identification will be helpful to the treatment and prognosis of ARDS cases. Herein, we report a case of ARDS caused by occupational exposure to waterproofing spray. To our knowledge, inhalation of waterproofing spray is an uncommon cause of ARDS, and what makes our case special is that we ruled out concurrent infections with some pathogens by using metagenomic next-generation sequencing (mNGS) as an auxiliary diagnosis, which presents the most comprehensive etiological examination of similar reports. Case Presentation: A previously healthy 25 years old delivery man developed hyperpyrexia, chest tightness, cough and expectoration. The symptoms occurred and gradually exacerbated after exposure to a waterproofing spray. The chest computed tomography (CT) finding showed diffuse ground glass and infiltrative shadows in both lungs. The diagnosis of ARDS related to waterproofing spray was established on the basis of comprehensive differential diagnosis and etiological examination. The patient achieved good curative effect after proper systemic glucocorticoid therapy. Conclusions: The diagnosis and differential diagnosis of acute respiratory failure for outdoor workers, such as delivery drivers or hikers, should be considered whether toxic aerosol exposure exists from daily contacts. The case can educate the public that more attention should be paid to avoid exposure to these chemicals by aerosols/ingestion mode and some preventive strategies should be taken in occupational environment. The treatment effect of glucocorticoids is significant in ARDS patients with general chemical damage caused by inhaling toxic gases and substances.

Clinical Study of Acute Vasoreactivity Testing in Patients with Chronic Thromboembolic Pulmonary Hypertension.

BACKGROUND: The clinical significance of acute vasoreactivity testing (AVT) in patients with chronic thromboembolic pulmonary hypertension (CTEPH) remains unclear. We analyzed changes in hemodynamics and oxygenation dynamics indices after AVT in patients with CTEPH using patients with pulmonary arterial hypertension (PAH) as controls. METHODS: We analyzed retrospectively the results of AVT in 80 patients with PAH and 175 patients with CTEPH registered in the research database of Beijing Chao-Yang Hospital between October 2005 and August 2014. Demographic variables, cardiopulmonary indicators, and laboratory findings were compared in these two subgroups. A long-term follow-up was conducted in patients with CTEPH. Between-group comparisons were performed using the independent-sample t-test or the rank sum test, within-group comparisons were conducted using the paired t-test or the Wilcoxon signed-rank test, and count data were analyzed using the Chi-squared test. Survival was estimated using the Kaplan-Meier method and log-rank test. RESULTS: The rates of positive response to AVT were similar in the CTEPH (25/175, 14.3%) and PAH (9/80, 11.3%) groups (P > 0.05). Factors significantly associated a positive response to AVT in the CTEPH group were level of N-terminal pro-brain natriuretic peptide (≤1131.000 ng/L), mean pulmonary arterial pressure (mPAP, ≤44.500 mmHg), pulmonary vascular resistance (PVR, ≤846.500 dyn·s-1·m-5), cardiac output (CO, ≥3.475 L/min), and mixed venous oxygen partial pressure (PvO2, ≥35.150 mmHg). Inhalation of iloprost resulted in similar changes in mean blood pressure, mPAP, PVR, systemic vascular resistance, CO, arterial oxygen saturation (SaO2), mixed venous oxygen saturation, partial pressure of oxygen in arterial blood (PaO2), PvO2, and intrapulmonary shunt (Qs/Qt) in the PAH and CTEPH groups (all P > 0.05). The survival time in patients with CTEPH with a negative response to AVT was somewhat shorter than that in AVT-responders although the difference was not statistically significant (χ2 =3.613, P = 0.057). The survival time of patients with CTEPH who received calcium channel blockers (CCBs) was longer than that in the group with only basic treatment and not shorter than that of patients who receiving targeted drugs or underwent pulmonary endarterectomy (PEA) although there was no significant difference between the four different treatment regimens (χ2 =3.069, P = 0.381). CONCLUSIONS: The rates of positive response to AVT were similar in the CTEPH and PAH groups, and iloprost inhalation induced similar changes in hemodynamics and oxygenation dynamics indices. A positive response to AVT in the CTEPH group was significantly correlated with milder disease and better survival. Patients with CTEPH who cannot undergo PEA or receive targeted therapy but have a positive response to AVT might benefit from CCB treatment.

[The DNA binding activity of nuclear factor-ΚB in patients with severe pneumonia and the intervention effects of Xuebijing injection].

OBJECTIVE: To investigate the role of nuclear factor-ΚB (NF-ΚB) in severe pneumonia and observe the effects of Xuebijing injection in its treatment. METHODS: Thirty hospitalized patients with severe pneumonia were divided into the routine therapy group (n=14) and Xuebijing therapy group (n=16) in whom with Xuebijing injection 100 ml was given once daily for 7 days besides routine therapies, according to the random numeral. The DNA binding activity of NF-ΚB in human monocytes was detected before and 3 days and 7 days after administration, the contents of tumor necrosis factor-α (TNF-α), procalcitonin (PCT) and C-reactive protein (CRP) were determined, and the changes in coagulatory and fibrinolytic parameters were assayed at the same time. Acute physiology and chronic health evaluationII (APACHEII) score was also recorded. Ten healthy volunteers served as the healthy control group. RESULTS: The DNA binding activities of NF-ΚB, the contents of TNF-α, PCT, CRP, fibrinogen (Fib), D-dimer in hospitalized subjects with severe pneumonia were higher before treatment than those in healthy control group, while the prothrombin time (PT), thrombin time (TT) were significantly lower (P<0.05 or P<0.01). Compared with the routine therapy group, the DNA binding activity of NF-ΚB (grey level) at the 7 days (66.60±36.23 vs. 79.90±39.11) was notably decreased in Xuebijing therapy group; the levels of TNF-α (ng/L, 25.81±11.67 vs. 33.78±13.36), PCT (µg/L, 1.91±1.09 vs. 2.96±1.80), CRP (mg/L, 20.01±7.21 vs. 26.59±10.66), Fib (g/L, 4.02±1.26 vs. 5.09±1.43), D-dimer (mg/L, 0.24±0.06 vs. 0.31±0.11) were significantly lower in Xuebijing therapy group, and APACHEII score (15.81±3.47 vs. 17.93±3.05) was obviously lowered (all P<0.05). There was statistical difference of the TT (s) between two groups at 3 days (15.68±1.89 vs. 14.65±1.33,P<0.05). There was a significant positive correlation between NF-ΚB DNA binding activity and the levels of TNF-α (r(1)=0.373, r(2)=0.362, r(3)=0.419), PCT (r (1)=0.800, r(2)=0.716, r(3)=0.920) or CRP (r(1)=0.368, r(2)=0.441, r(3)=0.366, all P<0.05) before and 3 days and 7 days after the treatment. CONCLUSION: NF-ΚB activation and coagulopathy were observed in patients with severe pneumonia, and NF-ΚB was involved in the process of inflammatory response. Inflammatory response was partly alleviated by Xuebijing injection. These effects of Xuebijing injection may be mediated by inhibition of the activation of NF-ΚB and its anticoagulation property.

[Effects of ventilation in prone position combined with recruitment maneuver on lung injury in dogs with acute respiratory distress syndrome].

OBJECTIVE: To evaluate protective effect and its mechanism of prone position ventilation (PPV) combined with recruitment maneuver (RM) as a lung protective ventilation strategy on oleic acid-induced acute respiratory distress syndrome (ARDS) in dogs. METHODS: Twenty-four oleic acid-induced ARDS dogs were ventilated with volume controlled ventilation (VCV): 16 cm H2O (1 cm H2O=0.098 kPa) of positive end-expiratory pressure (PEEP) and 10 ml/kg of tidal volume (VT). All dogs were randomly divided by random digit table into four groups: supine position (SP group), prone position (PP group), supine position+RM (SPRM group), and prone position+RM (PPRM group, 6 in each group), and ventilated by VCV for 4 hours and then sacrificed by exsanguination. The serum levels of inflammatory mediators were measured respectively at 0.5, 2 and 4 hours. After they were sacrificed, the levels of cytokines in left lung tissue homogenate were measured. The wet/dry weight ratio of right lung was determined and histological sections of the lungs were prepared and examined. RESULTS: (1) At 4 hours, interleukin-8 (IL-8) in serum in the SPRM group was significantly higher than in other three groups (all P<0.05), tumor necrosis factor-alpha (TNF-alpha) in serum in the SPRM group was significantly higher than in the PP group and the PPRM group (all P<0.05). (2) IL-8 in lung tissue homogenate of the dorsal aspect of the lung in the SP group was higher than in the PP group and the PPRM group (both P<0.05). TNF-alpha in lung tissue homogenate at the dorsal aspect of the lung in the SPRM group was higher than in the PP group and the PPRM group (both P<0.05). (3) Wet/dry weight ratio of right lung in the PP group and the PPRM group were significantly lower than that in the SP group and the SPRM group (all P<0.05). (4)Pathology score of lung tissue at the dorsal aspect of the lung in the PP group and PPRM group was significantly lower than in the SP group and the SPRM group (all P<0.05). CONCLUSION: Protective ventilation strategy combined with RM is safer in prone position than supine position, and it alleviates lung injury in dog with ARDS.

[Effects of prone position ventilation combined with recruitment maneuver on oxygenation and shunt in canines with acute respiratory distress syndrome].

OBJECTIVE: To evaluate the effects of prone position ventilation (PPV) combined with recruitment maneuver (RM) on oxygenation and intrapulmonary shunting in oleic acid-induced acute respiratory distress syndrome (ARDS) in canines while ventilated with lung protective ventilation strategy. METHODS: ARDS was induced by oleic acid in 24 dogs, and the animals were ventilated with volume controlled ventilation (VCV), 16 cm H2O (1 cm H2O = 0.098 kPa) of positive end-expiratory pressure (PEEP) and small tidal volumes (V(T) 10 ml/kg). All the dogs were randomly divided by random digit table into 4 groups (6 each), a control group (supine position, SP group), a prone position group (PP group), a supine position + RM group (SPRM group), and a prone position + RM group (PPRM group), and then were ventilated by VCV for 4 h. Arterial and mixed venous blood gas analyses were measured. Data were analyzed using the SPSS for windows (version 11.5). Results were expressed as x +/- s. Homogeneity of variance test was performed. The differences in means were calculated using one-way ANOVA. Post-hoc multiple comparisons of means were performed using Least Significant Difference. Nonparametric tests for several independent samples were performed to compare differences between the ranks in the groups studied. P value of < 0.05 was considered statistically significant. RESULTS: (1) At 15 min, PaO2/FiO2 in the SPRM group, the PP group and the PPRM group [(368 +/- 45) mm Hg (1 mm Hg = 0.133 kPa), (349 +/- 80) mm Hg, ( 423 +/- 43) mm Hg, respectively] was significantly higher than that in the SP group [(269 +/- 72) mm Hg, q = 2.77, 2.23, 4.31, respectively, all P < 0.05]. At 2 h, PaO2/FiO2 in the PP group and the PPRM group [(401 +/- 82) mm Hg, (416 +/- 23) mm Hg, respectively] was significantly higher than that in the SP group [(232 +/- 40) mm Hg, q = 3.99, 4.35, respectively, all P < 0.05]. At 4 h, PaO2/FiO2 in the PPRM group [(384 +/- 68) mm Hg] was significantly higher than that in the SP group [(256 +/- 75) mm Hg], that in the SPRM group [(267 +/-92) mm Hg] and that in the PP group [(284 +/- 83) mm Hg, q = 2.75, 2.56, 2.17, respectively, all P < 0.05]. (2) Intrapulmonary shunt (Q(S)/Q(T)) in the PP group was significantly decreased compared with that in the SP group from 30 min to 2 h [30 min (9.9 +/- 4.4)% vs (15.0 +/- 1.6)%, 1 h (9.7 +/- 4.5)% vs (16.0 +/- 2.0)%, 2 h (8.3 +/- 4.6)% vs (16.2 +/- 1.8)%, q = 2.86, 3.00, 3.65, respectively, all P < 0.05]. The Q(S)/Q(T), in the PPRM group was significantly decreased compared with that in the SP group from 30 min to 4 h [30 min (10.0 +/- 1.0)% vs (15.0 +/- 1.6)%, 1 h (10.4 +/- 2.7)% vs (16.0 +/- 2.0)%, 2 h (10.2 +/- 0.7)% vs (16.2 +/- 1.8)%, 4 h (10.1 +/- 1.1)% vs (15.7 +/- 1.7)%, q = 2.80, 2.67, 2.75, 2.99, respectively, all P < 0.05]. CONCLUSIONS: On the basis of small tidal volume lung and PEEP protective ventilation strategy, combining prone position and recruitment maneuver was more effective and showed a synergistic effect on improving oxygenation and intrapulmonary shunt.