The cardiovascular response to lower body negative pressure in humans depends on seal location.
We tested whether seal location at iliac crest (IC) or upper abdomen (UA), before and during lower body negative pressure (LBNP), would affect thoracic electrical impedance, hepatic blood flow, and central cardiovascular responses to LBNP. After 30 min of supine rest, LBNP at -40 mm Hg was applied for 15 min, either at IC or UA, in 14 healthy males. Plasma density and indocyanine green concentrations assessed plasma volume changes and hepatic perfusion. With both sealing types, LBNP-induced effects remained unchanged for mean arterial pressure (-3.0+/-1.1 mm Hg), cardiac output (-1.0 l min(-1)), and plasma volume (-11 %). Heart rate was greater during UA (80.6+/-3.3 bpm) than IC (76.0+/-2.5 bpm) (p<0.01) and thoracic impedance increased more using UA (3.2+/-0.2 Omega) than IC (1.8+/-0.2 Omega) (p<0.0001). Furthermore, during supine rest, UA was accompanied by lower thoracic impedance (26.9+/-1.1 vs 29.0+/-0.8 Omega, p<0.001) and hepatic perfusion (1.6 vs 1.8 l.min(-1), p<0.05) compared to IC. The data suggest that the reduction in central blood volume in response to LBNP depends on location of the applied seal. The sealing in itself altered blood volume distribution and hepatic perfusion in supine resting humans. Finally, application of LBNP with the seal at the upper abdomen induced a markedly larger reduction in central blood volume and greater increases in heart rate than when the seal was located at the iliac crest. (+info)
Nitric oxide and cardiovascular and renal effects.
Realtime photoacoustic microscopy of murine cardiovascular dynamics.
Non-invasive visualization of cardiovascular dynamics in small animals is challenging due to their rapid heart-rates. We present a realtime photoacoustic imaging system consisting of a 30-MHz ultrasound array transducer, receive electronics, a high-repetition-rate laser, and a multicore-computer, and demonstrate its ability to image optically-absorbing structures of the beating hearts of young athymic nude mice at rates of approximately 50 frames per second with 100 microm x 25 microm spatial resolution. To our knowledge this is the first report of realtime photoacoustic imaging of physiological dynamics. (+info)
Safety and feasibility of aerobic training on cardiopulmonary function and quality of life in postsurgical nonsmall cell lung cancer patients: a pilot study.
Percutaneous cervical cordotomy is an invasive procedure to treat severe, opioid-resistant cancer pain. It is usually proposed for patients with a limited life expectancy. As a consequence, objective quantification of the long-term effects of this procedure is lacking. The present report describes a patient who was treated with a right-sided percutaneous cervical cordotomy for refractory cancer pain. Afterward, disseminated seminoma was diagnosed, which was cured with chemotherapy. Five years after the procedure, a qualitative and quantitative evaluation of the long-term effects was performed. Sensory dysfunction was observed in the left side of the body, but no motor neuron or autonomic dysfunction was observed. The influence of these long-term effects on the patient's daily activities was limited. (+info)