Intracranial pressure pulse amplitude during changes in head elevation: a new parameter for determining optimum cerebral perfusion pressure?

During short-term postural changes, the factors determining the amplitude of intracranial pulse pressure (ICPPA) remain constant, except for cerebrovascular resistance (CVR). Therefore, it may be possible to draw conclusions from the ICPPA onto the cerebrovascular resistance (CVR) and thus the relative change in cerebral perfusion pressure (CPP).

Pulse or hyaline ring granuloma. Review of the literature on etiopathogenesis of oral and extraoral lesions

Since the late 1950s, reports on an unusual giant-cell granulomatous lesion affecting the jaws, lungs, stomach and intestines have been published. Histopathologically, the lesions showed the presence of structureless hyaline rings with multinucleated giant cells. The aim of this review was to summarize the literature on the etiopathogenesis of the so-called oral and extraoral pulse or hyaline ring granuloma. Literature was searched using PubMed and Medline. In addition, hand search was performed. Search words were oral and extraoral hyaline ring granuloma, giant-cell hyaline angiopathy, pulse granuloma and chronic periostitis. Numerous terms for hyaline ring granuloma have been introduced over time (1971-2008). One hundred seventy-three cases of oral hyaline ring granuloma have been retrieved from the literature. In the mandible, 72.3% occurred . Two theories for etiopathogenesis have been proposed: (1) the origin of the hyaline rings is due to a foreign material (pulse and legumes) having penetrated the oral mucosa or gastrointestinal tract and lungs (exogenous theory) and (2) the rings are due to hyaline degenerative changes in walls of blood vessels (endogenous theory). Experimental production of oral and extraoral hyaline ring granulomas is consistent with the exogenous origin. Particles or remains of leguminous cells having been implanted or aspirated into human tissues whether located to the oral cavity or throughout the entire digestive tract and respiratory system are thought to be causative. Pulse or hyaline ring granulomas are rare but are well-defined oral and extraoral lesions due to implantation of the cellulose moiety of plant foods in contrast to the starch components.

Pulse-pressure variation and hemodynamic response in patients with elevated pulmonary artery pressure: a clinical study

Pulse-pressure variation (PPV) due to increased right ventricular afterload and dysfunction may misleadingly suggest volume responsiveness. We aimed to assess prediction of volume responsiveness with PPV in patients with increased pulmonary artery pressure.

Pulse pressure variation and volume responsiveness during acutely increased pulmonary artery pressure: an experimental study

We found that pulse pressure variation (PPV) did not predict volume responsiveness in patients with increased pulmonary artery pressure. This study tests the hypothesis that PPV does not predict fluid responsiveness during an endotoxin-induced acute increase in pulmonary artery pressure and right ventricular loading.

Comparison of non-calibrated pulse-contour analysis with continuous thermodilution for cardiac output assessment in patients with induced hypothermia after cardiac arrest

Induced mild hypothermia after cardiac arrest interferes with clinical assessment of the cardiovascular status of patients. In this situation, non-invasive cardiac output measurement could be useful. Unfortunately, arterial pulse contour is altered by temperature, and the performance of devices using arterial blood pressure contour analysis to derive cardiac output may be insufficient.

Chest pulse-wave velocity: a novel approach to assess arterial stiffness

Pulse-wave velocity (PWV) is considered as the gold-standard method to assess arterial stiffness, an independent predictor of cardiovascular morbidity and mortality. Current available devices that measure PWV need to be operated by skilled medical staff, thus, reducing the potential use of PWV in the ambulatory setting. In this paper, we present a new technique allowing continuous, unsupervised measurements of pulse transit times (PTT) in central arteries by means of a chest sensor. This technique relies on measuring the propagation time of pressure pulses from their genesis in the left ventricle to their later arrival at the cutaneous vasculature on the sternum. Combined thoracic impedance cardiography and phonocardiography are used to detect the opening of the aortic valve, from which a pre-ejection period (PEP) value is estimated. Multichannel reflective photoplethysmography at the sternum is used to detect the distal pulse-arrival time (PAT). A PTT value is then calculated as PTT = PAT - PEP. After optimizing the parameters of the chest PTT calculation algorithm on a nine-subject cohort, a prospective validation study involving 31 normo- and hypertensive subjects was performed. 1/chest PTT correlated very well with the COMPLIOR carotid to femoral PWV (r = 0.88, p < 10 (-9)). Finally, an empirical method to map chest PTT values onto chest PWV values is explored.

The ocular pulse amplitude at different intraocular pressure: a prospective study

To investigate changes in ocular pulse amplitude (OPA) during a short-term increase in intraocular pressure (IOP) and to assess possible influences of biometrical properties of the eye, including central corneal thickness (CCT) and axial length.