3D-quantitated lung perfusion SPECT/CT: Impact on intended management compared to lung perfusion scan in marginal candidates for lung resection surgery

Objective

Based on previous studies, single-photon emission computed tomography/computed tomography (SPECT/CT) has been proven to be more accurate and reproducible than planar lung perfusion scintigraphy. We conducted a study to evaluate the impact of 3D-quantitated lung perfusion SPECT/CT on intended management in candidates for lung resection surgery.

Methods

Retrospective study including candidates for lung resection surgery with lung perfusion imaging. Patients underwent preoperative evaluation according to ERS/ESTS algorithm. The lobar contribution to the total lung perfusion was estimated using planar antero-posterior, posterior oblique and three-dimensional anatomical SPECT/CT method (CT Pulmo 3D and xSPECT- Quant, Siemens). The difference in lobar perfusion with resulting changes in the extent of lung resection were analyzed to reveal possible changes in operability.

Results

120 patients (46 females) with known lung cancer or pulmonary lesion considered for resection with available lung perfusion scintigraphy and SPECT/CT were enrolled. The mean age (±SD) of patients was 68 ±9 years, the target lesions were located in upper lobe in 57.7% and in lower lobe in 33.5%. The median [IQR] FEV1 was 70.5% [52–84] and median DLCO 56.6% [47.1–67.4]. The planar posterior oblique method, compared to 3D-quantitated SPECT/CT, underestimated the perfusion of upper lobes by a median difference of 5% (right [2–9; IQR]; left [2.5–8], p= < 0.0001), while it overestimated the both lower lobes (left by 4% [2–7]; right by 6% [2–9], p= < 0.0001). In contrast to the planar scintigraphy based evaluation, 4(3.3%) patients with upper lobe lesions were classified as inoperable when 3D-quantitated SPECT/CT was used for calculation of predicted postoperative lung function.

Conclusion

In selected patients with upper lobe lesions, 3D-quantitated SPECT/CT would have changed the treatment strategy from operable to inoperable. Importantly, post-operative mortality in this particular subgroup was disproportionally high. 3D-quantitated SPECT/CT shall be further evaluated as it might improve preoperative risk stratification in marginal lung resection candidates.

Telehealth mitigates COPD disease progression compared to standard of care: a randomized controlled crossover trial

BACKGROUND

We showed excellent adherence and satisfaction with our telehealth care (TC) approach for COPD. Here, the results of a consecutive randomized controlled trial are presented.

METHODS

Patients were randomly assigned to TC or standard care (SC). During TC, patients answered six daily questions online, and focused on the early recognition of exacerbations, in addition to SC.

RESULTS

The mean increase in COPD assessment test (CAT) was 1.8 vs. 3.6 points/year in the TC and SC groups, respectively (P = 0.0015). Satisfaction with care (VAS) at baseline was 8.2; at the end of SC, 8.5 (P = 0.062); and after TC, 8.8 (P < 0.001). We detected significantly more moderate exacerbations during TC.

CONCLUSION

Whilst receiving TC, the slope of the CAT increase - an indicator of the naturally progressive course of COPD - was reduced by 50%. Satisfaction with care increased with TC. The higher number of detected moderate exacerbations probably indicates a higher diagnostic sensitivity than without TC.

Chronological Bias in Randomized Clinical Trials Arising from Different Types of Unobserved Time Trends

Background: In clinical trials patients are commonly recruited sequentially over time incurring the risk of chronological bias due to (unobserved) time trends. To minimize the risk of chronological bias, a suitable randomization procedure should be chosen.

Objectives: Considering different time trend scenarios, we aim at a detailed evaluation of the extent of chronological bias under permuted block randomization in order to provide recommendations regarding the choice of randomization at the design stage of a clinical trial and to assess the maximum extent of bias for a realized sequence in the analysis stage.

Methods: For the assessment of chronological bias we consider linear, logarithmic and stepwise trends illustrating typical changes during recruitment in clinical practice. Bias and variance of the treatment effect estimator as well as the empirical type I error rate when applying the t-test are investigated. Different sample sizes, block sizes and strengths of time trends are considered.

Results: Using large block sizes, a notable bias exists in the estimate of the treatment effect for specific sequences. This results in a heavily inflated type I error for realized worst-case sequences and an enlarged mean squared error of the treatment effect estimator. Decreasing the block size restricts these effects of time trends. Already applying permuted block randomization with two blocks instead of the random allocation rule achieves a good reduction of the mean squared error and of the inflated type I error. Averaged over all sequences, the type I error of the t-test is far below the nominal significance level due to an overestimated variance.

Conclusions: Unobserved time trends can induce a strong bias in the treatment effect estimate and in the test decision. Therefore, already in the design stage of a clinical trial a suitable randomization procedure should be chosen. According to our results, small block sizes should be preferred, but also medium block sizes are sufficient to restrict chronological bias to an acceptable extent if other contrary aspects have to be considered (e.g. serious risk of selection bias). Regardless of the block size, a blocked ANOVA should be used because the t-test is far too conservative, even for weak time trends.

Influence of Rhodiola rosea on the heat acclimation process in young healthy men

The adaptogen Rhodiola rosea (RR) may mitigate stress responses and have beneficial effects on endurance capacity (EC) and mental performance. Heat acclimation (HA) improves EC in the heat, but the potential impact of RR on the HA process is unknown. Therefore, our intent was to determine if RR has a positive impact on HA. Twenty male subjects (age, 22.5 ± 3.0 years) completed 2 EC tests involving walking (6 km·h^-1) until volitional exhaustion in a climate chamber (air temperature, 42 °C; relative humidity, 18%) before (H1) and after (H2) an 8-day HA period. One group (SHR; n = 10) ingested standardised extract SHR-5 of RR (a single daily dose of 432 mg), while a second group (PLC; n = 10) administered a placebo prior to each HA session. Efficacy of HA was evaluated on the basis of changes that occurred from H1 to H2 in the time to exhaustion (TTE), exercise heart rate (HR), core and skin temperatures (T_c, T_sk), stress hormones, ratings of perceived exertion (RPE) and fatigue (RPF), and thermal sensation (TS). HA significantly increased TTE (133.1 ± 44.1 min in H1; 233.4 ± 59.8 min in H2; p < 0.0001) and decreased (p < 0.0001) HR, T_c, T_sk, stress hormones as well as RPE, RPF, and TS. However, the magnitude of all these changes was similar (p > 0.05) in the SHR and PLC groups. These results suggest that the use of RR during HA has no beneficial performance, physiological, or perceptual effects in young healthy males.

Effects of caffeine on endurance capacity and psychological state in young females and males exercising in the heat

Acute caffeine ingestion is considered effective in improving endurance capacity and psychological state. However, current knowledge is based on the findings of studies that have been conducted on male subjects mainly in temperate environmental conditions, but some physiological and psychological effects of caffeine differ between the sexes. The purpose of this study was to compare the physical performance and psychological effects of caffeine in young women and men exercising in the heat. Thirteen male and 10 female students completed 2 constant-load walks (60% of thermoneutral peak oxygen consumption on a treadmill until volitional exhaustion) in a hot-dry environment (air temperature, 42 °C; relative humidity, 20%) after caffeine (6 mg·kg–1) and placebo (wheat flour) ingestion in a double-blind, randomly assigned, crossover manner. Caffeine, compared with placebo, induced greater increases (p < 0.05) in heart rate (HR) and blood lactate concentrations in both males and females but had no impact on rectal or skin temperatures or on walking time to exhaustion in subjects of either gender. Caffeine decreased (p < 0.05) ratings of perceived exertion and fatigue in males, but not in females. In females, but not in males, a stronger belief that they had been administered caffeine was associated with a shorter time to exhaustion. In conclusion, acute caffeine ingestion increases HR and blood lactate levels during exercise in the heat, but it has no impact on thermoregulation or endurance capacity in either gender. Under exercise-heat stress, caffeine reduces ratings of perceived exertion and fatigue in males but not in females.

Eigenvalue tunneling and decay of quenched random network

We consider the canonical ensemble of N-vertex Erdős-Rényi (ER) random topological graphs with quenched vertex degree, and with fugacity μ for each closed triple of bonds. We claim complete defragmentation of large-N graphs into the collection of [p^{-1}] almost full subgraphs (cliques) above critical fugacity, μ_{c}, where p is the ER bond formation probability. Evolution of the spectral density, ρ(λ), of the adjacency matrix with increasing μ leads to the formation of a multizonal support for μ>μ_{c}. Eigenvalue tunneling from the central zone to the side one means formation of a new clique in the defragmentation process. The adjacency matrix of the network ground state has a block-diagonal form, where the number of vertices in blocks fluctuates around the mean value Np. The spectral density of the whole network in this regime has triangular shape. We interpret the phenomena from the viewpoint of the conventional random matrix model and speculate about possible physical applications.

Analgesia by telemedically supported paramedics compared with physician-administered analgesia: A prospective, interventional, multicentre trial

BACKGROUND

In German emergency medical services (EMS), the analgesia is restricted to physicians. In this prospective, interventional, multicentre trial, complications with and quality of telemedically delegated analgesia were evaluated.

METHODS

If prehospital analgesia was necessary, five telemedically equipped paramedic ambulances from four different districts could consult a telemedicine centre. Analgesics were delegated based on a predefined algorithm. Telemedically assisted cases were compared with local historical regular EMS missions using matched pairs. The primary outcome was the frequency of therapeutic complications (respiratory/circulatory insufficiency, allergic reactions). Secondary outcomes were quality of analgesia (11-point numerical rating scale, NRS) and the frequency of nausea/vomiting.

RESULTS

Analgesia was necessary in 106 telemedically assisted missions. In 23 cases, the telemedical procedure was used until an EMS physician arrived. Of the remaining 83 cases, 80 could be matched to comparable controls. Complications did not occur in either the study group or the control group (0 vs. 0; p = N/A). Complete NRS documentation was noted in 65/80 (study group) and 32/80 (control group) cases (p < 0.0001). Adequate initial pain reduction (quality indicator: reduction of NRS ≥ 2 points or NRS < 5 at end of mission) occurred in 61/65 versus 31/32 cases (p = 1.0); NRS reduction during mission was 3.78 ± 2.0 versus 4.38 ± 2.2 points (p = 0.0159). Nausea and vomiting occurred with equal frequency in both groups.

CONCLUSIONS

Telemedical delegation of analgesics to paramedics was safe and led to a pain reduction superior to the published minimum standard in both groups. The documentation quality was better in the telemedicine group. WHAT DOES THIS STUDY ADD?: Little is known about the safety and quality of prehospital analgesia carried out by emergency medical services (EMS). Beside potential quality problems, in some countries meaningful pain reduction is limited by legal regulations that allow only physicians to administer analgesics. This first multicentre prospective trial for telemedically delegated analgesia demonstrates that remote analgesia is possible and safe and retains equivalent analgesic quality compared with that administered by onsite EMS physicians.

[Evaluation of the German version of the caregiver reaction assessment questionnaire for informal caregivers of patients with neovascular age-related macular degeneration]

BACKGROUND

Informal caregivers of patients with loss of vision often have to give physical and emotional support because of the high level of dependence induced. Although it is known that these informal caregivers suffer a higher risk of being affected by burn-out syndrome or depression, the various dimensions of burden, especially of informal caregivers of patients with neovascular age-related macular degeneration (nv-AMD) have not yet been investigated.

OBJECTIVE

The objective of this study was the evaluation of the German version of the caregiver reaction assessment (CRA) questionnaire in a collective of informal caregivers of patients with nv-AMD. In this context the positive and negative influences on the informal caregivers were assessed.

MATERIAL AND METHODS

Between January 2013 and July 2014 a total of 150 informal caregivers of patients with nv-AMD filled out the CRA independently using a questionnaire survey which had been translated into German. Based on this collective, the psychometric characteristics of the translated questionnaire were evaluated.

RESULTS

The informal caregivers of the current collective reported a lower burden in the five subgroups disrupted schedule, lack of family support, self-esteem, health problems and financial problems, compared to the previous CRA studies with caregivers of patients with other diseases. The informal caregivers saw the greatest burden as the disruption of their schedule. Through a principal component analysis the five subgroups could be identified as five factors. It was shown that 19 out of the 24 items could be assigned to the same factors as in the original English version. The internal consistency of the five subgroups was acceptable except for the subscale on self-esteem.

CONCLUSION

In this study the CRA has been confirmed as a suitable instrument to assess both positive and negative reactions of informal caregivers related to caregiving of patients with nv-AMD. The results provide support for a five subscale structure of the CRA in the original English version but five items of the questionnaire could be assigned to another subscale.

Emotional modulation of attention affects time perception: evidence from event-related potentials

Emotional effects on human time perception are generally attributed to arousal speeding up or slowing down the internal clock. The aim of the present study is to investigate the less frequently considered role of attention as an alternative mediator of these effects with the help of event-related potentials (ERPs). Participants produced short intervals (0.9, 1.5, 2.7, and 3.3s) while viewing high arousal images with pleasant and unpleasant contents in comparison to neutral images. Behavioral results revealed that durations were overproduced for the 0.9s interval whereas, for 2.7 and 3.3s intervals, underproduction was observed. The effect of affective valence was present for the shorter durations and decreased as the target intervals became longer. More specifically, the durations for unpleasant images were less overproduced in the 0.9s intervals, and for the 1.5s trials, durations for unpleasant images were slightly underproduced, compared to pleasant images, which were overproduced. The analysis of different ERP components suggests possible attention processes related to the timing of affective images in addition to changes in pacemaker speed. Early Posterior Negativity (EPN) was larger for positive than for negative images, indicating valence-specific differences in activation of early attention mechanisms. Within the early P1 and the Late Positive Potential (LPP) components, both pleasant and unpleasant stimuli exhibited equal affective modulation. Contingent Negative Variation (CNV) remained independent of both timing performance and affective modulation. This pattern suggests that both pleasant and unpleasant stimuli enhanced arousal and captured attention, but the latter effect was more pronounced for pleasant stimuli. The valence-specificity of affective attention revealed by ERPs combined with behavioral timing results suggests that attention processes indeed contribute to emotion-induced temporal distortions, especially for longer target intervals.

Anatomic changes of target vessels after fenestrated and branched aortic aneurysm repair

AIM

Objective of this study was to evaluate the anatomic changes of the stented target vessels after endovascular repair of complex aortic aneurysms.

METHODS

Between July 2011 and December 2013, 53 aortic aneurysms were treated in our department with fenestrated and branched stent-graft devices. Forty-two of these patients were pre- and postoperatively scanned with a high resolution computer tomography (CT) (Cook Zenith® fenestrated or branched, Australia Pty. Ltd., Brisbane, Australia: N.=19; AnacondaTM fenestrated, Vascutek, Glasgow, Scotland, UK: N.=23). The other 11 out of the 53 patients did not receive a CT scan, because of a pre-existing renal failure. In the CT scans we retrospectively evaluated the anatomic vessel deviation at the origin of the target vessel and the vessel shift distal to the stent. For the first measurement the CT scans were loaded into OsiriX MD®, and the pre- and postoperative angles of the target vessels were measured and subtracted. For matching, the CT-scans were normalized at vertebral body lumbar 2. The second measured angle was the maximal measured angle distal to the target vessel stent-graft.

RESULTS

Altogether, 113 target vessels were stented (celiac trunk [CT] 15, superior mesenteric arteries [SMA] 26, renal arteries [RA] 72), with 97 balloon-expandable PTFE stents: 90 Atrium V12 (Maquet Getinge group, Hudson, NH, USA), 7 BeGrafts (Bentley InnoMed, Hechingen, Germany) and 16 self-expandable fluency PTFE stents (Bard, Karlsruhe, Germany). The mean anatomic deviation at the target vessel origin was 28±17.3 and the mean vessel shift distal to the stent was 36.3±18.8. There were no significant differences between the main device and the target vessel stent types.

CONCLUSION

Fenestrated and branched stent-graft solutions for aortic aneurysm repair induce changes of the target vessel anatomy. We did not observe significant differences between the several devices.

Heat acclimation decreases the growth hormone response to acute constant-load exercise in the heat

OBJECTIVE

The major objective of this study was to elucidate the effect of heat acclimation on blood growth hormone (GH) response to moderate intensity exhausting exercise in the heat. In addition, the potential relationship between inter-individual differences in GH response to exercise and variability in exercise-induced sweat loss was investigated.

DESIGN

Twenty young men completed three exercise tests on a treadmill: H1 (walk at 60% VO₂peak until exhaustion at 42 °C), N (walk at 22 °C; duration equal to H1) and H2 (walk until exhaustion at 42 °C after a 10-day heat acclimation program). Core temperature (T(c)) was recorded continuously and venous blood samples were taken before, during and after each exercise test. Exercise-induced sweat production was calculated on the basis of body mass change taking into account water intake and the volume of blood samples drawn.

RESULTS

Lower pre-exercise T(c), lower rate of rise in T(c) during exercise, and prolonged time to exhaustion in H2 compared with H1 revealed that the subjects successfully achieved an acclimated state. Overall, serum GH level was higher in H1 compared with both N and H2 (p<0.001) but did not differ between the two latter trials (p>0.05). T(c) correlated with serum GH concentration (r=0.615, p<0.01). Analysis of the individual data revealed a group (n=9) possessing a threshold-like pattern of the relationship between T(c) and blood GH response, whereas a plateau-like pattern was evident in the rest of the subjects (n=11). Both sweat production (r=0.596; p<0.001) and the rate of sweat production (r=0.457; p<0.001) correlated with the growth hormone area under the curve.

CONCLUSION

Heat acclimation decreases the GH response to moderate intensity exhausting exercise in the heat. GH may have a modest stimulating effect on whole-body sweat production during exercise.

Visual evoked potentials to change in coloration of a moving bar

In our previous study we found that it takes less time to detect coloration change in a moving object compared to coloration change in a stationary one (Kreegipuu etal., 2006). Here, we replicated the experiment, but in addition to reaction times (RTs) we measured visual evoked potentials (VEPs), to see whether this effect of motion is revealed at the cortical level of information processing. We asked our subjects to detect changes in coloration of stationary (0(°)/s) and moving bars (4.4 and 17.6(°)/s). Psychophysical results replicate the findings from the previous study showing decreased RTs to coloration changes with increase of velocity of the color changing stimulus. The effect of velocity on VEPs was opposite to the one found on RTs. Except for component N1, the amplitudes of VEPs elicited by the coloration change of faster moving objects were reduced than those elicited by the coloration change of slower moving or stationary objects. The only significant effect of velocity on latency of peaks was found for P2 in frontal region. The results are discussed in the light of change-to-change interval and the two methods reflecting different processing mechanisms.

Unintentionality of affective attention across visual processing stages

Affective attention involves bottom-up perceptual selection that prioritizes motivationally significant stimuli. To clarify the extent to which this process is automatic, we investigated the dependence of affective attention on the intention to process emotional meaning. Affective attention was manipulated by presenting affective images with variable arousal and intentionality by requiring participants to make affective and non-affective evaluations. Polytomous rather than binary decisions were required from the participants in order to elicit relatively deep emotional processing. The temporal dynamics of prioritized processing were assessed using early posterior negativity (EPN, 175–300 ms) as well as P3-like (P3, 300–500 ms) and slow wave (SW, 500–1500 ms) portions of the late positive potential. All analyzed components were differentially sensitive to stimulus categories suggesting that they indeed reflect distinct stages of motivational significance encoding. The intention to perceive emotional meaning had no effect on EPN, an additive effect on P3, and an interactive effect on SW. We concluded that affective attention went from completely unintentional during the EPN to partially unintentional during P3 and SW where top-down signals, respectively, complemented and modulated bottom-up differences in stimulus prioritization. The findings were interpreted in light of two-stage models of visual perception by associating the EPN with large-capacity initial relevance detection and the P3 as well as SW with capacity-limited consolidation and elaboration of affective stimuli.

The compression of perceived time in a hot environment depends on physiological and psychological factors

The human perception of time was observed under extremely hot conditions. Young healthy men performed a time production task repeatedly in 4 experimental trials in either a temperate (22 °C, relative humidity 35%) or a hot (42 °C, relative humidity 18%) environment and with or without a moderate-intensity treadmill exercise. Within 1 hour, the produced durations indicated a significant compression of short intervals (0.5 to 10 s) in the combination of exercising and high ambient temperature, while neither variable/condition alone was enough to yield the effect. Temporal judgement was analysed in relation to different indicators of arousal, such as critical flicker frequency (CFF), core temperature, heart rate, and subjective ratings of fatigue and exertion. The arousal-sensitive internal clock model (originally proposed by Treisman) is used to explain the temporal compression while exercising in heat. As a result, we suggest that the psychological response to heat stress, the more precisely perceived fatigue, is important in describing the relationship between core temperature and time perception. Temporal compression is related to higher core temperature, but only if a certain level of perceived fatigue is accounted for, implying the existence of a thermoemotional internal clock.

Dietary sodium citrate supplementation enhances rehydration and recovery from rapid body mass loss in trained wrestlers

This study assessed the effects of dietary sodium citrate supplementation during a 16 h recovery from 5% rapid body mass loss (RBML) on physiological functions, affective state, and performance in trained wrestlers. Sixteen wrestlers performed an upper body intermittent sprint performance (UBISP) test under three conditions: before RBML, after RBML, and after a 16 h recovery from RBML. During recovery, the subjects ate a prescribed diet supplemented with sodium citrate (600 mg·kg(-1); CIT group, N = 8) or placebo (PLC group, N = 8) and drank water ad libitum. RBML reduced (p < 0.05) UBISP mean power and increased urine specific gravity (USG). Reduction in mean power was associated with changes in plasma volume (PV) (r = 0.649, p = 0.006) and USG (r = -0.553, p = 0.026). During the 16 h recovery, increases in body mass (BM) and PV were greater (p < 0.05) in the CIT group than in the PLC group. BM gain was associated with water retention in the CIT group (r = 0.899, p = 0.002) but not in the PLC group (r = 0.335, p = 0.417). Blood pH, HCO(3)(-) concentration, and base excess increased (p < 0.05) only in the CIT group. Changes in UBISP, general negative affect, and general positive affect did not differ in the two groups. In conclusion, ingestion of sodium citrate increases blood buffering capacity and PV and stimulates BM regain during a 16 h recovery from RBML in trained wrestlers. However, sodium citrate does not improve UBISP nor does it have an impact on the affective state.

[Occupational rhinitis and asthma]

Allergic rhinoconjunctivits and asthma are frequent diseases. About one in ten asthma cases is caused by an occupational hazard, either by an allergic or a non-immunologic mechanism. Primary or secondary preventive measures should be able to prevent these cases. Often, occupational rhinitis precedes the development of occupational asthma. Important causative agents are flours, plant and enzyme powders, laboratory animals, latex, isocyanates and hardeners, epoxy resins, acrylates, formaldehyde and welding fumes. Early diagnosis and the installation of protective measures are decisive for the prognosis of occupational respiratory disease.

Influence of selection bias on the test decision. A simulation study

BACKGROUND

Selection bias arises in clinical trials by reason of selective assignment of patients to treatment groups. Even in randomized clinical trials with allocation concealment this phenomenon can occur if future assignments can be predicted due to knowledge of former allocations.

OBJECTIVES

Considering unmasked randomized clinical trials with allocation concealment the impact of selection bias on type I error rate under permuted block randomization is investigated. We aimed to extend the existing research into this topic by including practical assumptions concerning misclassification of patient characteristics to get an estimate of type I error close to clinical routine. To establish an upper bound for the type I error rate different biasing strategies of the investigator are compared first. In addition, the aspect of patient availability is considered.

METHODS

To evaluate the influence of selection bias on type I error rate under several practical situations, different block sizes, selection effects, biasing strategies and success rates of patient classification were simulated using SAS.

RESULTS

Type I error rate exceeds 5 percent significance level; it reaches values up to 21 percent. More cautious biasing strategies and misclassification of patient characteristics may diminish but cannot eliminate selection bias. The number of screened patients is about three times larger than the needed number for the trial.

CONCLUSIONS

Even in unmasked randomized clinical trials using permuted block randomization with allocation concealment the influence of selection bias must not be disregarded evaluating the test decision. It should be incorporated when designing and reporting a clinical trial.

Cigarette smoke inhibits lung fibroblast proliferation by translational mechanisms

Cigarette smoke is a major cause of chronic obstructive pulmonary disease (COPD) and emphysema. Although cigarette smoke represses cellular proliferation, the molecular mechanisms underlying this phenomenon are unknown. CCAAT/enhancer-binding proteins (C/EBPs) are key regulators of cell cycle progression, differentiation and pro-inflammatory gene expression, are regulated predominantly at the translational level and may be involved in the pathogenesis of COPD. The aim of this study was to assess the effect of cigarette smoke on proliferation and the expression and translational regulation of C/EBPα and C/EBPβ in nondiseased primary human lung fibroblasts. Fibroblasts were exposed to cigarette smoke-conditioned medium (10% and 20% for 24 h). Proliferation was determined by [(3)H]thymidine incorporation. Protein expression levels were determined by immunoblotting and translation was monitored using a translation control reporter system. Cigarette smoke significantly reduced fibroblast proliferation and significantly upregulated full-length C/EBPα and C/EBPβ proteins due to a shift in the translational control of CEBPA and CEBPB mRNAs. This shift involved the re-initiation of mRNA translation via the regulatory upstream open reading frame, which coincided with increased interleukin-8 release and a decrease in functional elastin level. These findings provide a novel mechanism to understanding the tissue remodelling observed in the lungs of COPD patients.

Propofol versus propofol plus hydrocodone for flexible bronchoscopy: a randomised study

Propofol and the combination of a benzodiazepine and an opiate have been established for sedation in flexible bronchoscopy. It is as yet unknown whether propofol in combination with an opiate is superior to propofol alone to suppress cough during the procedure. 300 consecutive patients undergoing flexible bronchoscopy at a tertiary care university hospital were randomly allocated to receive either the combination propofol and hydrocodone or propofol alone in a double-blind fashion. The primary end-point was the cough score during the procedure as estimated by the physician using a visual analogue scale. Demographics were similar in both groups. Compared with propofol alone, median (interquartile range) cough scores assessed by physicians, nurses and patients were significantly lower in the group randomised to the combination propofol and hydrocodone (2.5 (1.5-4.0) versus 2.0 (1.0-3.0), respectively, p=0.011). Additionally, patients receiving the combination required significantly lower doses of propofol than those receiving propofol alone (200 mg (140-280) versus 260 mg (180-350), p<0.0001). Complex examinations, including bronchoalveolar lavage or transbronchial biopsy, benefited more from additional opiate. The duration of the procedure, time to discharge and complication rate were similar in both groups. The combination of propofol and hydrocodone is safe and superior to propofol alone for cough suppression in flexible bronchoscopy.

House dust mite extract downregulates C/EBPα in asthmatic bronchial smooth muscle cells

Reduced translation of CEBPA mRNA has been associated with increased proliferation of bronchial smooth muscle (BSM) cells of asthma patients. Here, we assessed the effect of house dust mite (HDM) extracts on the cell proliferation ([(3)H]-thymidine incorporation), inflammation (interleukin (IL)-6 release) and upstream translation regulatory proteins of CCAAT/enhancer-binding protein (C/EBP)α in human BSM cells of healthy controls and asthmatic patients. HDM extract significantly increased IL-6 protein and proliferation of BSM cells of asthma patients only. HDM extract reduced the C/EBPα expression in BSM cells of asthma patients, which coincided with significantly increased levels of calreticulin (CRT) protein, an inhibitor of CEBPA mRNA translation. HDM extract elicited both protease-dependent and -independent responses, which were mediated via protease-activated receptor (PAR)2 and CRT, respectively. In conclusion, HDM extract reduced CEBPA mRNA translation, specifically in asthmatic BSM cells, and 1) upregulated CRT, 2) activated PAR2, and increased 3) IL-6 expression and 4) the proliferation of asthmatic BSM cells. Hence, HDM exposure contributes to inflammation and remodelling by a nonimmune cell-mediated mechanism via a direct interaction with BSM cells. These findings may potentially explain several pathological features of this disease, in particular BSM cell hyperplasia.

General practitioner's adherence to the COPD GOLD guidelines: baseline data of the Swiss COPD Cohort Study

PRINCIPLES: Chronic obstructive pulmonary disease (COPD) is a major burden on patients and healthcare systems. Diagnosis and the management of COPD are often administered by general practitioners (GPs). This analysis investigated the adherence of GPs in Switzerland to the Global Initiative for Chronic Obstructive Lung Diseases (GOLD) guidelines. METHODS: As part of an ongoing investigation into the effect of GPs prescriptions on the clinical course of COPD, 139 GPs submitted a standardised questionnaire for each COPD patient recruited. Information requested included spirometric parameters, management and demographic data. Participating GPs were provided with and received instruction on a spirometer with automatic feedback on quality. Patients were grouped by the investigators into the GOLD COPD severity classifications, based on spirometric data provided. Data from the questionnaires were compared between the groups and management was compared with the recommendations of GOLD. RESULTS: Of the 615 patients recruited, 44% did not fulfil GOLD criteria for COPD. Pulmonary rehabilitation was prescribed to 5% of all patients and less than one-third of patients exercised regularly. Less than half the patients in all groups used short-acting bronchodilators. Prescribing long-acting bronchodilators or inhaled corticosteroids conformed to GOLD guidelines in two-thirds of patients with GOLD stage III or IV disease, and approximately half of the less severe patients. Systemic steroids were inappropriately prescribed during stable disease in 6% of patients. CONCLUSIONS: Adherence to GOLD (COPD) guidelines is low among GPs in Switzerland and COPD is often misdiagnosed or treated inappropriately. This is probably due to poor knowledge of disease definitions.

Midregional pro-atrial natriuretic peptide and procalcitonin improve survival prediction in VAP

Ventilator-associated pneumonia (VAP) affects mortality, morbidity and cost of critical care. Reliable risk estimation might improve end-of-life decisions, resource allocation and outcome. Several scoring systems for survival prediction have been established and optimised over the last decades. Recently, new biomarkers have gained interest in the prognostic field. We assessed whether midregional pro-atrial natriuretic peptide (MR-proANP) and procalcitonin (PCT) improve the predictive value of the Simplified Acute Physiologic Score (SAPS) II and Sequential Related Organ Failure Assessment (SOFA) in VAP. Specified end-points of a prospective multinational trial including 101 patients with VAP were analysed. Death <28 days after VAP onset was the primary end-point. MR-proANP and PCT were elevated at the onset of VAP in nonsurvivors compared with survivors (p = 0.003 and p = 0.017, respectively) and their slope of decline differed significantly (p = 0.018 and p = 0.039, respectively). Patients with the highest MR-proANP quartile at VAP onset were at increased risk for death (log rank p = 0.013). In a logistic regression model, MR-proANP was identified as the best predictor of survival. Adding MR-proANP and PCT to SAPS II and SOFA improved their predictive properties (area under the curve 0.895 and 0.880). We conclude that the combination of two biomarkers, MR-proANP and PCT, improve survival prediction of clinical severity scores in VAP.

Quality of spirometry in primary care for case finding of airway obstruction in smokers

BACKGROUND

Diagnosis of chronic obstructive pulmonary disease (COPD) and its severity determination is based on spirometry. The quality of spirometry is crucial.

OBJECTIVES

Our aim was to assess the quality of spirometry performed using a spirometer with automated feedback and quality control in a general practice setting in Switzerland and to determine the prevalence of airflow limitation in smokers aged > or =40 years.

METHOD

Current smokers > or =40 years of age were consecutively recruited for spirometry testing by general practitioners. General practitioners received spirometry training and were provided with an EasyOne spirometer. Spirometry tests were assigned a quality grade from A to D and F, based on the criteria of the National Lung Health Education Program. Only spirometry tests graded A-C (reproducible measurements) were included in the analysis of airflow limitation.

RESULTS

A total of 29,817 spirometries were analyzed. Quality grades A-D and F were assigned to 33.9, 7.1, 19.4, 27.8 and 11.8% of spirometries, respectively. 95% required < or =5 trials to achieve spirometries assigned grade A. The prevalence of mild, moderate, severe and very severe airway obstruction in individuals with spirometries graded A-C was 6, 15, 5 and 1%, respectively.

CONCLUSION

Spirometries in general practice are of acceptable quality with reproducible spirometry in 60% of measurements. Airway obstruction was found in 27% of current smokers aged > or =40 years. Office spirometry provides a simple and quick means of detecting airflow limitation, allowing earlier diagnosis and intervention in many patients with early COPD.

Procalcitonin for reduced antibiotic exposure in ventilator-associated pneumonia: a randomised study

In patients with ventilator-associated pneumonia (VAP), guidelines recommend antibiotic therapy adjustment according to microbiology results after 72 h. Circulating procalcitonin levels may provide evidence that facilitates the reduction of antibiotic therapy. In a multicentre, randomised, controlled trial, 101 patients with VAP were assigned to an antibiotic discontinuation strategy according to guidelines (control group) or to serum procalcitonin concentrations (procalcitonin group) with an antibiotic regimen selected by the treating physician. The primary end-point was antibiotic-free days alive assessed 28 days after VAP onset and analysed on an intent-to-treat basis. Procalcitonin determination significantly increased the number of antibiotic free-days alive 28 days after VAP onset (13 (2-21) days versus 9.5 (1.5-17) days). This translated into a reduction in the overall duration of antibiotic therapy of 27% in the procalcitonin group (p = 0.038). After adjustment for age, microbiology and centre effect, the rate of antibiotic discontinuation on day 28 remained higher in the procalcitonin group compared with patients treated according to guidelines (hazard rate 1.6, 95% CI 1.02-2.71). The number of mechanical ventilation-free days alive, intensive care unit-free days alive, length of hospital stay and mortality rate on day 28 for the two groups were similar. Serum procalcitonin reduces antibiotic therapy exposure in patients with ventilator associated pneumonia.