[Lung transplantation for pulmonary emphysema--who, when, how?]

End stage pulmonary emphysema is the most common indication for lung transplantation worldwide. The shortness of donor organs and the better natural prognosis compared to other diseases leading to transplantation such as pulmonary fibrosis and cystic fibrosis demands careful patient selection.Lung transplantation is considered in patients with declining lung function after receiving all conservative treatment options including smoking cessation and rehabilitation programmes. Preoperative evaluation using consensus criteria needs to be performed by a multidisciplinary team in specialized centres. Assessment of co-morbidities is crucial, as they may significantly increase transplant-related mortality. The largest survival advantage from lung transplantation has been shown for the subgroup of patients below 60 years of age presenting with end-stage obstructive lung disease (FEV1 < 20% predicted) and respiratory failure. Similarly, high risk patients with secondary pulmonary hypertension or cachexia (BMI < 20) will likely benefit from transplantation.The 5-year-survival rate averages 60 percent, with superior outcome following double versus single lung transplantation. A clear survival benefit can only be achieved in a subgroup of patients, whereas the impact on quality of life seems to be even more important in patients suffering from chronic obstructive pulmonary disease.

Olfactory detection thresholds and pleasantness of a food-related and a non-food odour in hunger and satiety

The primary aim of this study was to investigate whether olfactory detection thresholds are dependent on different states of satiety. Using the threshold test of the Sniffin' Sticks test battery (single-staircase, three alternative forced choice procedure), sensitivity to a non-food odour (n-butanol) and a food-related odour (isoamyl acetate) was investigated. Twenty-four healthy, female subjects (mean age 24.2 years, SD 2.7 years) with normal olfactory function performed the tests when hungry and when satiated. Additionally, they rated their emotional condition, arousal, alertness as well as the intensity and pleasantness of both odorants. No significant change in the detection thresholds for the non-food odour n-butanol, but a significant change in detection threshold for the food-related odour isoamyl acetate was found. The detection threshold for isoamyl acetate was significantly lower in the state of satiety compared to the hungry condition. As expected, the perceived pleasantness of isoamyl acetate was significantly lower in satiety. In summary, the results indicate that in our experimental setting the actual state of satiety has effects on detection thresholds of a food-related odour, but not of a non-food odour. Interestingly, the higher sensitivity was found during the state of satiety challenging the current hypothesis that control of food intake is supported by a decrease in sensitivity to food odours. Instead our findings that satiety decreases the pleasantness of a food-related odour support the hypothesis that both odour threshold as well as pleasantness play an important role in the control of food intake.

Effects of laserneedle acupuncture on olfactory sensitivity of healthy human subjects: a placebo-controlled, double-blinded, randomized trial

The aims of the present study were to investigate the influence of laserneedle acupuncture on olfactory sensitivity and to examine whether the attitude towards laserneedle acupuncture affects the outcome. Olfaction was tested repeatedly on two days using the olfactory detection threshold subtest of the Sniffin' Sticks test battery in sixty-four healthy subjects of which 32 showed a positive attitude towards the effects of laserneedle acupuncture and 32 were sceptic about its effects. Testing was accomplished three times on day one (T1 = 0 min, T2 = 35 min, T3 = 105 min) without laserneedle acupuncture and on day two (T1* = 0 min, T2* = 35 min, T3* = 105 min) when the subjects were randomized in a non-stimulation (placebo) and a stimulation (laserneedle acupuncture) group. Stimulation or non-stimulation was conducted in a double-blinded design. Following laserneedle acupuncture a significant decrease in olfactory detection thresholds was observed at both, T2* and T3*, whereas no significant changes were found in the baseline or placebo group. Effects of laserneedle acupuncture on the olfactory detection threshold did not differ between sceptic and non-sceptic subjects. In conclusion, laserneedle acupuncture is an effective method to improve olfactory sensitivity after one session of stimulation for at least one hour, independently of the attitude of subjects towards the stimulation method.

Investigation of breathing parameters during odor perception and olfactory imagery

Compared with visual and auditory imagery, little is known about olfactory imagery. There is evidence that respiration may be altered by both olfactory perception and olfactory imagery. In order to investigate this relationship, breathing parameters (respiratory minute volume, respiratory amplitude, and breathing rate) in human subjects during olfactory perception and olfactory imagery were investigated. Fifty-six subjects having normal olfactory function were tested. Nasal respiration was measured using a respiratory pressure sensor. Using an experimental block design, we alternately presented odors or asked the subjects to imagine a given smell. Four different pleasant odors were used: banana, rose, coffee, and lemon odor. We detected a significant increase in respiratory minute volume between olfactory perception and the baseline condition as well as between olfactory imagery and baseline condition. Additionally we found significant differences in the respiratory amplitude between imagery and baseline condition and between odor and imagery condition. Differences in the breathing rate between olfactory perception, olfactory imagery, and baseline were not statistically significant. We conclude from our results that olfactory perception and olfactory imagery both have effects on the human respiratory profile and that these effects are based on a common underlying mechanism.