Masui. The Japanese journal of anesthesiology
-
Since the advent of ultrasound-guided peripheral nerve block, it has been thought that this new technique has many advantages over conventional ones. However, few of them have been confirmed yet. Nor is it free from problems that are associated with peripheral nerve block itself. ⋯ There are clearly some limitations today for imaging smaller and deeper nerves. The needle placement with ultrasound guidance requires skills which conventional techniques do not. Therefore, it would be prudent to think that this new technique carries a similar risk of complications and requires similar amount of training to conventional ones.
-
The ultrasound waves (> 20 kHz) are high-frequency sound waves that are not audible to the human ear. As the ultrasound waves move through body tissues of different acoustic impedances, they are attenuated, reflected, or scattered. Reflected waves are transformed back into an electrical signal that is processed by the ultrasound machine to generate an image on the screen. ⋯ The recent advance of ultrasonography has provided close-sectional images of the body in real time. Ultrasound imaging has been useful to visualize neural anatomical structures and the surrounding structures, and navigate the needle toward the target nerves. This review introduces the theories and practices of ultrasonography for the peripheral nerve blocks.
-
During several months of 2002, severe acute respiratory syndrome (SARS) caused by SARS-coronavirus (SARS-CoV) spread rapidly from China throughout the world causing more than 800 deaths due to the development of acute respiratory distress syndrome (ARDS). Interestingly, a novel homologue of angiotensin converting-enzyme (ACE), termed angiotensin converting enzyme 2 (ACE2) has been identified as a receptor for SARS-CoV. ACE and ACE2 share homology in their catalytic domain and provide different key functions in the renin-angiotensin system. ⋯ Importantly, our recent studies using ACE2 knockout mice have demonstrated that ACE2 protects murine lungs from ARDS. Furthermore, SARS-CoV infections and the Spike protein of the SARS-CoV reduce ACE2 expression. Notably, injection of SARS-CoV Spike into mice worsens acute lung failure in vivo that can be attenuated by blocking the renin-angiotensin pathway, suggesting the activation of pulmonary RAS influences the pathogenesis of ARDS and SARS.
-
In this decade, the molecular mechanism of sepsis has been strikingly clarified. Especially, the identification of toll-like receptors as the pivotal molecules for the recognition of the stimulation of the inflammatory products of microorganisms has contributed to the elucidation of intracellular signaling pathways which result in severe systemic inflammatory response in sepsis. The production and release of a variety of pro-inflammatory mediators have been found to be associated with severe systemic inflammation and multiple organ dysfunction syndrome (MODS). ⋯ Despite of the advance in the basic research regarding molecular pathophysiology of sepsis, sepsis is still accompanied by high mortality in clinical settings. Almost all clinical trials targeting sepsis-associated mediators have failed, except the substitution therapy of activated protein C. However, further trials based on the basic findings, including the therapies targeting the multiple mediators, will contribute to the improvement of outcome of clinical sepsis. ple organ dysfunction syndrome (MODS), pro-inflammatory mediator, disseminated intravascular coagulopathy (DIC).
-
Review Comparative Study
[Pharmacodynamics and pharmacokinetics of remifentanil: overview and comparison with other opioids].
In this review, the authors tried to summarize the characteristics and main differences of remifentanil with other opioids, and to overview its pharmacodynamics and pharmacokinetics. Clearance and volume of distribution of remifentnail are extremely different from other conventional opioids. ⋯ As remifentanil is metabolized by a non-specific esterase, excretion of remifentnil is predictable in basically all patients undergoing general anesthesia and surgery. Therefore, remifentanil is considered to be an optimal opioid as an analgesic combined either with inhalational anesthetics or intravenous hypnotics in balanced general anesthesia.