Intensive care medicine
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Intensive care medicine · Oct 2006
Effects of vertical positioning on gas exchange and lung volumes in acute respiratory distress syndrome.
Supine position may contribute to the loss of aerated lung volume in patients with acute respiratory distress syndrome (ARDS). We hypothesized that verticalization increases lung volume and improves gas exchange by reducing the pressure surrounding lung bases. ⋯ Vertical positioning is a simple technique that may improve oxygenation and lung recruitment in ARDS patients.
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Intensive care medicine · Oct 2006
Bedside echocardiographic evaluation of hemodynamics in sepsis: is a qualitative evaluation sufficient?
Transesophageal echocardiography (TEE) has proven its efficiency in assessing hemodynamics in patients by its ability to evaluate cardiac function and fluid responsiveness. Classically, it requires quantitative measurements, whereas in routine practice TEE is used in our unit especially as a qualitative procedure. We assessed the accuracy of this qualitative central hemodynamic evaluation obtained by TEE at the bedside. ⋯ By its ability accurately to evaluate hemodynamic status qualitative TEE could be useful for intensivists in managing circulatory failure in septic shock, rendering the more time-consuming quantitative evaluation useless.
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Intensive care medicine · Oct 2006
Renal failure in septic shock: predictive value of Doppler-based renal arterial resistive index.
Because acute renal failure (ARF) is frequent in septic shock, an early marker of ARF could impact on management of such patients. High renal arterial resistive index (RI) is associated with parenchymatous renal failure. We assessed whether Doppler-measured RI on day 1 (D1) of septic shock can predict ARF. ⋯ Doppler-based determination of RI on D1 in septic shock patients may help identify those who will develop ARF.
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Intensive care medicine · Oct 2006
Ability of pulse contour and esophageal Doppler to estimate rapid changes in stroke volume.
Two technologies to acquire beat-to-beat stroke volume values exist, pulse contour analysis and esophageal Doppler monitoring. Pulse contour analysis assumes fixed aortic impedance. Esophageal Doppler assumes a constant proportional descending aortic flow and diameter. These assumptions may not be correct as arterial tone or myocardial contractility vary. We tested these relationships in the setting of rapidly changing stroke volumes and different cardiovascular states over a period of 10-15 cardiac cycles. ⋯ Both pulse contour stroke volumes and esophageal Doppler derived stroke distance estimates yield significant correlations with aortic root flow probe. However, the absolute values, absolute changes, or proportional changes may not reflect actual stroke volumes as cardiovascular state varies, making their use in estimating absolute changes in stroke volume potentially inaccurate.