Stefan Hammerschmidt

Exhaled breath condensate acidification in acute lung injury

Lung injury in ventilated lungs may occur due to local or systemic disease and is usually caused by or accompanied by inflammatory processes. Recently, acidification of exhaled breath condensate pH (EBC-pH) has been suggested as marker of inflammation in airway disease. We investigated pH, ammonia, Lactate, pCO2, HCO3-, IL-6 and IL-8 in EBC of 35 ventilated patients (AECC-classification: ARDS: 15, ALI: 12, no lung injury: 8). EBC-pH was decreased in ventilated patients compared to volunteers (5.85 +/- 0.32 vs. 7.46 +/- 0.48; P < 0.0001). NH4+, lactate, HCO3-, pCO2, IL-6 and IL-8 were analyzed in EBC and correlated with EBC-pH. We observed correlations of EBC-pH with markers of local (EBC IL-6: r = -0.71, P < 0.0001, EBC IL-8: r = -0.68, P < 0.0001) but not of systemic inflammation (serum IL-6, serum IL-8) and with indices of severity of lung injury (Murrays Lung Injury Severity Score; r = -0.73, P < 0.0001, paO2/FiO2; r = 0.54, P < 0.001). Among factors potentially contributing to pH of EBC, EBC-lactate and EBC-NH4+ were found to correlate with EBC-pH. Inflammation-induced disturbances of regulatory mechanisms, such as glutaminase systems may result in EBC acidification. EBC-pH is suggested to represent a marker of acute lung injury caused by or accompanied by pulmonary inflammation.

Multiplex Analysis of Cytokines in Exhaled Breath Condensate

To improve monitoring of lung diseases, we analyzed cytokines in exhaled breath condensate (EBC). The main challenge in measurement of cytokines in EBC is the low protein content, which requires concentration steps that conflict with the need for excessive fluid required by most commonly used kits.

Effects of nasal high flow on ventilation in volunteers, COPD and idiopathic pulmonary fibrosis patients.

Background: A high flow of air applied by large bore nasal cannulae has been suggested to improve symptoms of chronic respiratory insufficiency. In pediatric patients, nasal high-flow (nHF) ventilation was similarly effective compared to noninvasive ventilation with a face mask. Objectives: The aim of this study was to describe changes in respiratory parameters. Methods: We measured pressure amplitudes during the respiratory cycle and mean pressures in patients with idiopathic pulmonary fibrosis (IPF) and COPD. In order to achieve tidal volume and minute volume measurements, we used a polysomnography device. Capillary blood was taken for blood gas analysis before and after nHF breathing (8 h). Results: nHF led to an increase in pressure amplitude and mean pressure in healthy volunteers and in patients with COPD and IPF in comparison with spontaneous breathing. In COPD, nHF increased tidal volume, while no difference in tidal volume was observed in patients with IPF. Interestingly, tidal volume decreased in healthy volunteers. Breathing rates and minute volumes were reduced in all groups. Capillary pCO2 decreased in patients with IPF and COPD. Conclusions: nHF resulted in significant effects on respiratory parameters in patients with obstructive and restrictive pulmonary diseases. The rise in pressure amplitude and mean pressure and the decrease in breathing rate and minute volume will support inspiratory efforts, helps to increase effectiveness of ventilation and will contribute to a reduction in the work of breathing. A CO2 wash-out effect in the upper airway part of the anatomical dead space may contribute to the beneficial effects of the nHF instrument.

Long-Term Bosentan in Chronic Thromboembolic Pulmonary Hypertension

Background: There is no approved pharmacological treatment for patients with chronic thromboembolic pulmonary hypertension (CTEPH) who are not suitable for pulmonary endarterectomy (PEA). Objective: The study investigates the effect of the dual endothelin receptor antagonist bosentan on exercise tolerance (6-min walking distance, 6MWD) and right ventricular function (Tei index) in patients with CTEPH over 24 months. Methods: Twelve consecutive patients (5 males and 7 females) with CTEPH not eligible for PEA or following partial or complete failure of PEA were included in a non-randomized, open-label prospective study. All patients were WHO class III. They were included, if progressive pulmonary hypertension was diagnosed despite best supportive treatment. Bosentan was started at 62.5 mg b.i.d. and increased to the final dose of 125 mg b.i.d. Results: 6MWD and the Tei index were assessed every 6 months. We observed a significant increase in 6MWD from 319 ± 85.0 m at baseline to 391 ± 76.9 m at 6 months and a significant decrease in the Tei index from 0.39 ± 0.10 at baseline to 0.34 ± 0.08 at 6 months. This improvement was maintained over 24 months (6 MWD: 381 ± 101 m; Tei index: 0.31 ± 0.03). Six patients exhibited an improvement in WHO class at 6, 12 and 18 months, 5 demonstrated improvement at the 24-month follow-up. The remainder were stable throughout the study period. Conclusion: This is the first study demonstrating a long-term beneficial effect of bosentan on exercise tolerance (6MWD) and right heart function (Tei index) in CTEPH.

Role of functional groups of human plasma and luminol in scavenging of NaOCl and neutrophil-derived hypochlorous acid

Hypochlorous acid HOCl/OCl- and other oxidants derived from stimulated polymorphonuclear leukocytes are involved in tissue damage during a number of pathological processes. In order to obtain more detailed information on possible reactions of HOCl/OCl- the effects of both NaOCl and PMN-derived hypochlorous acid on functional groups of amino acid solutions and human plasma are studied. In valine and lysine solutions NaOCl diminishes the number of amino groups in a molar ratio of 1:1 between NaOCl and amino groups. In cysteine and methionine samples the decrease of amino groups starts only after all sulfhydryl or thioether groups are oxidized by NaOCl. If freshly prepared human plasma is treated with increasing amounts of NaOCl all plasma SH groups are oxidized first, then probably the thioether groups and only after this the amino groups are affected. Furthermore, it was found, that the reactivity of luminol against NaOCl is similar to that of amino groups. Increasing amounts of SH groups of components of human plasma are oxidized by incubation with PMA-stimulated polymorphonuclear leukocytes dependent on the incubation time. Plasma amino groups are not affected under the same experimental conditions. The addition of plasma to FMLP-stimulated PMN in the presence of luminol decreases that part of chemiluminescence caused by extracellularly generated hypochlorous acid. Plasma samples pretreated with NaOCl cause a lower inhibition of light generation in FMLP-stimulated PMN only when more than 4.10(-8) mol NaOCl per mg protein are used to pretreat plasma. It is assumed that in the development of tissue injuries caused by infiltrated PMN the following sequence of damage occurs in accessible tissue regions. First, the sulfhydryl groups are oxidized, then the thioether groups, and only after this amino and other target groups are affected.

Angiogenic markers in breath condensate identify non-small cell lung cancer

Early recognition of lung cancer is a prerequisite for any strategy to improve lung cancer treatment outcome. Here we report a cross-sectional study intended as a proof of principle investigation using breath based detection (exhaled breath condensate, EBC) of angiogenic markers (VEGF, bFGF, angiogenin), TNF-alpha and IL-8 to discriminate 74 individuals, with confirmed presence or absence (X-ray, CT) of non-small lung cancer (NSCLC). Levels of angiogenic markers bFGF, angiogenin and VEGF in EBC significantly discriminated between 17 individuals with newly detected NSCLC versus stable and exacerbated chronic obstructive pulmonary disease (COPD) patients as well as healthy volunteers. Levels of IL-8 and TNF-alpha in EBC indicated acute inflammation, e.g. in acute exacerbated COPD (AECOPD) and were not indicative of lung cancer. In a different group of patients that were already treated with two cycles of chemotherapy and who responded with at least a 25% reduction in primary tumor diameter, levels of angiogenic markers were lower compared to patients with newly diagnosed NSCLC. We suggest that breath based detection of angiogenic markers may help in the early detection of lung cancer.

Lung Cancer: Current Diagnosis and Treatment

BACKGROUND Much progress has been made in the treatment of lung cancer in the last ten years (adjuvant chemotherapy, targeted therapy, individualized therapy). Nonetheless, lung cancer is still the leading cause of death due to cancer and thus remains a major medical, scientific, and social problem. METHOD This review is based on national and international recommendations and selected articles from the literature. RESULTS Cigarette smoking is the major pathogenic factor for lung cancer. Lung cancer can be divided into two major types that differ in their biological behavior, small cell lung cancer and non-small cell lung cancer. Whenever possible, the diagnosis should be confirmed by biopsy, the extent of disease should be documented in detail (international TNM classification/staging), and the patients functional level should be assessed with a view toward treatment planning. Surgery for non-small cell lung cancer with curative intent is possible up to stage IIIA, while stage IIIB is the domain of radiotherapy. Surgery for small cell lung cancer with curative intent is possible for rare cases in early stages (T1N0 and T2N0, i.e., stage IA and IB). As long as small cell lung cancer is restricted to one side of the chest, simultaneous radiation therapy and chemotherapy are indicated. If a malignant pleural effusion or distant metastases are present, both lung cancers are treated palliatively with platinum-based chemotherapy.

Inhaled iloprost for the control of pulmonary hypertension

Pulmonary arterial hypertension (PAH) is a life-threatening disease characterized by an elevated pulmonary arterial pressure and vascular resistance with a poor prognosis. Various pulmonary and extrapulmonary causes are now recognized to exist separately from the idiopathic form of pulmonary hypertension. An imbalance in the presence of vasoconstrictors and vasodilators plays an important role in the pathophysiology of the disease, one example being the lack of prostacyclin. Prostacyclin and its analogues are potent vasodilators with antithrombotic, antiproliferative and anti-inflammatory qualities, all of which are important factors in the pathogenesis of precapillary pulmonary hypertension. Iloprost is a stable prostacyclin analogue available for intravenous and aerosolized application. Due to the severe side effects of intravenous administration, the use of inhaled iloprost has become a mainstay in PAH therapy. However, owing to the necessity for 6 to 9 inhalations a day, oral treatment is often preferred as a first-line therapy. Numerous studies proving the efficacy and safety of inhaled iloprost have been performed. It is therefore available for a first-line therapy for PAH. The combination with endothelin-receptor antagonists or sildenafil has shown encouraging effects. Further studies with larger patient populations will have to demonstrate the use of combination therapy for long-term treatment of pulmonary hypertension.

Influence of tidal volume on pulmonary NO release, tissue lipid peroxidation and surfactant phospholipids.

Mechanical stress during ventilation may cause or aggravate acute lung injury. This study investigates the influence of low vs. high tidal volume (V(t)) on factors known to play key roles in acute lung injury: nitric oxide release, eNOS and iNOS gene expression, lipid peroxidation (LPO), and surfactant phospholipids (PL). Isolated rabbit lungs were subjected to one of three ventilation patterns for 135 min (V(t)-PEEP): 6 ml/kg-0 cm H(2)O. 12 ml/kg-0 cm H(2)O 6 ml/kg-5 cm H(2)O, 12 ml/kg-0 cm H(2)O, and 6 ml/kg-5 cm H(2)O resulted in comparable peak inspiratory pressure (PIP). This allowed comparing low and high V(t) without dependence on PIP. Ventilatory patterns did not induce changes in pulmonary artery pressure, vascular permeability (K(f,c)), PIP or pulmonary compliance. High V(t) in comparison with both of the low V(t) groups caused an increase in BALF-nitrite (30.6+/-3.0* vs. 21.4+/-2.2 and 16.2+/-3.3 microM), BALF-PL (1110+/-19* vs. 750+/-68 and 634+/-82 microg/ml), and tissue LPO product accumulation (0.62+/-0.051* vs. 0.48+/-0.052 and 0.43+/-0.031 nmol/mg), *P<0.05 each. Perfusate nitrite and BALF-PL composition (assessed by use of 31P-NMR spectroscopy and MALDI-TOF mass spectrometry) did not differ among the groups. High V(t) ventilation reduced eNOS gene expression but did not affect iNOS expression. The increased release of NO and the accumulation of LPO products may represent early lung injury while elevated BALF-PL may reflect distension-induced surfactant secretion.

Lipid analysis of bronchoalveolar lavage fluid (BAL) by MALDI–TOF mass spectrometry and 31P NMR spectroscopy

Despite the high clinical relevance, only the cellular moiety of bronchoalveolar lavage (BAL) has been intensively investigated and is used for diagnosis purposes. On the other hand, the cell-free fluid is, by far, less characterized. Although this fluid represents a relatively simple mixture of only a few different phospholipids (mainly phosphatidylcholine, phosphatidylglycerol and cholesterol), methods for the routine analysis of these fluids are still lacking. In the present investigation we have applied, for the first time, MALDI-TOF mass spectrometry, as well as 31P NMR spectroscopy to the analysis of organic extracts of bronchoalveolar lavage fluids. BAL from different mammals (rat, minipig, rabbit and man) were investigated and, for means of comparison, organic extracts of lung tissue were also examined. Both applied methods provide fast and reliable information on the lipid composition of the bronchoalveolar lavage. However, despite of its comparably low sensitivity, 31P NMR spectroscopy detects all phospholipid species in a single experiment and with the same sensitivity, whereas MALDI-TOF fails in the detection of phosphatidylethanolamine in the presence of higher quantities of phosphatidylcholine. In contrast, MALDI-TOF mass spectrometry is more suitable for the detection of cholesterol and the determination of the fatty acid composition of the individual phospholipids, especially lysolipids. It will be shown that all BALs exhibit significant, species-dependent differences that mainly concern the content of phosphatidylglycerol and lyso-phosphatidylcholine. It is concluded that both methods are suitable tools in lipid research due to the (in comparison to alternative methods) simplicity of performance.