PubMed HealthSearch

PubMed · 9791782

Precipitous decrease in blood pressure in acute ischemic stroke patients during transesophageal echocardiography: a case study from the adult brain attack database.

Abstract

Transesophageal echocardiography is often the diagnostic modality used for evaluation of cardiovascular sources of cerebral emboli. While invasive, TEE has proven to be a safe diagnostic method. However, TEE may have hemodynamic consequences within the procedure that are potentially hazardous to the specific population of acute ischemic stroke patients. As the case study and resultant discussion illustrated, specific interventions may theoretically interrupt the possible mechanisms responsible for the precipitous decrease in blood pressure. Further investigation of methods to prevent precipitous decrease in blood pressure and to identify potential negative outcomes for ischemic stroke patients must continue within the clinical setting.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

T Shephard, H Shebelski. 1998. Precipitous decrease in blood pressure in acute ischemic stroke patients during transesophageal echocardiography: a case study from the adult brain attack database.. https://doi.org/10.1097/01376517-199808000-00008

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

IL-5 mediates eosinophilic rejection of MHC class II-disparate skin allografts in mice.

CD4 T cells play a crucial role in the acute rejection of MHC class II-disparate skin allografts, mainly by Fas/Fas ligand-mediated cytotoxicity. Because recent observations indicate that eosinophils may be found within allografts rejected by CD4 T cells, we evaluated the role played by IL-5, the main eosinophil growth factor, and by eosinophils in the rejection of MHC class II-disparate skin grafts. C57BL/6 mice rapidly rejected MHC class II-disparate bm12 skin grafts. Rejected skins contained a dense, aggressive eosinophil infiltrate. Lymphocytes isolated from lymph nodes draining rejected bm12 skin were primed for IL-5 secretion, and IL-5 mRNA was present within rejected grafts. The IL-5/eosinophil pathway played an effector role in allograft destruction, because the rejection of bm12 skin was significantly delayed in IL-5-deficient mice as compared with wild-type animals. The role of the IL-5/eosinophil pathway was further investigated in MHC class II-disparate donor-recipient strains unable to establish Fas/Fas ligand interactions. Fas ligand-deficient gld/gld mice rejected bm12 skins, and bm12 mice rejected Fas-deficient lpr/lpr C57BL/6 skins. Neutralization of IL-5 prevented acute rejection in both combinations. We conclude that MHC class II-disparate skin allografts trigger an IL-5-dependent infiltration of eosinophils that is sufficient to result in acute graft destruction.

Acute Disease

Treatment of HSV-1 infection with immunoglobulin or acyclovir: comparison of their effects on viral spread, latency, and reactivation.

We compared immunoglobulin (IgG) and acyclovir (ACV) therapies on the establishment, maintenance, and reactivation from latency of HSV-1(McKrae) in a mouse ocular infection model. Mice were given one intraperitoneal (IP) dose of human IgG 24 h after infection (Day 1 p. i.) or ACV in the drinking water from Days 1 to 7 p.i. Both treatments allowed similar percentages of mice to survive the infection and decreased ocular virus shedding as compared with untreated controls. At most time points, there were no differences between IgG- and ACV-treated animals with respect to tissue virus titers or in the rates of virus reactivation during explant cocultivation. However, after ultraviolet exposure, HSV reactivated in 30% of ACV-treated mice compared with 90% of IgG-treated mice (P = 0.02). Also by quantitative PCR, we found more latent HSV-1 DNA copies in IgG-treated mice compared with those given ACV (P = 0.02). IgG treatment protects mice from HSV-1 infection essentially as well as ACV does. Nonetheless, it permits higher levels of latent infection and subsequent in vivo reactivation. These studies have implications for the mechanism by which IgG functions to attenuate HSV infections and for its potential value as a therapeutic agent in humans.

Acute Disease

Neuronal activity and transcription of proinflammatory cytokines, IkappaBalpha, and iNOS in the mouse brain during acute endotoxemia and chronic infection with Trypanosoma brucei brucei.

Trypanosoma brucei brucei (Tbb) infection is a model of chronic immune response associated with severe neurological disorders believed to lead to coma and death. We hypothesized that exaggerated production of proinflammatory molecules within the cental nervous system (CNS) may be involved in the etiology of the disease, i.e., African Tripanosomiasis. The purpose of the present study was therefore to verify the effects of the parasite Tbb on the genetic expression of the immediate-early gene c-fos (index of cellular activity), tumor necrosis factor alpha (TNF-alpha), interleukin-6 (IL-6), inhibitory factor kappa B alpha (IkappaBalpha, index of the nuclear factor kappaB activity, the transcription factor of numerous proinflammatory molecules), and inducible nitric oxide synthase (iNOS) in the mouse brain. Adult male BALB/c mice received a single intraperitoneal injection of lipopolysaccharide (LPS, used as positive control for these markers that are induced in a transient manner by the endotoxin), Tbb, or vehicle solution and were sacrificed at multiple times (1 hr to 7 days) following the injection. Acute and chronic models induced a robust expression of c-fos in numerous regions of the brain, including the circumventricular organs (CVOs) and different nuclei involved in autonomic control. Although the effect of LPS was rapid and transient, Tbb pathogen stimulated c-fos only within 5 to 7 days. The genes encoding TNF-alpha and IL-6 cytokines were expressed in the CVOs and choroid plexus 1 and 3 hr after LPS injection, whereas no convincing hybridization signal was detected in the brains of Tbb-infected mice at any time. IL-6 and iNOS-expressing cells were also found along large blood vessels of LPS-treated mice, while scattered small TNF-alpha-expressing cells were observed across the brain 12 and 24 hr after the endotoxin treatment. Tbb caused a low to moderate expression of iNOS and IkappaBalpha genes in perivascular cells, but this effect was apparent only several days following the parasite infection. Taken together, these data indicate that LPS and Tbb stimulate c-fos expression in similar nuclei involved in autonomic control, an event occurring within the first 3 hr after the LPS insult and only 5 days post-Tbb injection. The mRNAs encoding proinflammatory cytokines were, however, not detected in Tbb-infected brains, which may be explained by the Tbb variant (MiTat 1.5) that caused high parasitaemias and mortality within 5 to 7 days.

Acute Disease