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741.

Background

To determine the optimum chest compression site during cardiopulmonary resuscitation (CPR) with regard to heart failure (HF) by applying three-dimensional (3D) coordinates on computed tomography (CT).

Methods

This retrospective, cross-sectional study involved adults who underwent echocardiography and CT on the same day from 2007 to 2017. Incomplete CT images or information on HF, cardiac medication between echocardiography and CT, or thoracic abnormalities were excluded. Cases were checked whether they had HF through symptom/sign assessment, N-terminal pro-B type natriuretic peptide, and echocardiography. We set the xiphisternal joint's midpoint as the reference (0, 0, 0) to draw a 3D coordinate system, designating leftward, upward, and into-the-thorax directions as positive. The coordinate of the maximum LV diameter's midpoint (P_max.LV) was identified.

Results

Enrolled were 148 patients (63.0 ± 15.1 years) with 87 females and 76 HF cases. P_max.LV of HF cases was located more leftwards, lower, and deeper than non-HF cases (5.69 ± 0.98, ? 1.51 ± 1.67, 5.76 ± 1.09 cm vs. 5.00 ± 0.83, ? 0.99 ± 1.36, 5.25 ± 0.71 cm, all p < 0.05). Fewer HF cases had their LV compressed than non-HF cases (59.2% vs. 77.8%, p = 0.025) when being compressed according to the current guidelines. The aorta (vs. LV) was compressed in 85.5% and 81.9% of HF and non-HF cases, respectively, at 3 cm above the xiphisternal joint. At 6 cm above the joint, the highest allowable position according to the current guidelines, all victims would have their aorta compressed directly during CPR rather than the LV.

Conclusions

The lowest possible sternum just above the xiphisternal joint should be compressed especially for HF patients during CPR.  相似文献   
742.
Hofmann E  Choné L 《HNO》2011,59(1):9-15
Magnetic resonance imaging (MRI) is the diagnostic gold standard in vestibular schwannoma. Sensitivity and specificity are both close to 100%. MRI detects the tumour and describes its extension, thereby giving the potential surgeon prognostic clues. Prediction of tumour growth, however, is not possible. Careful analysis of imaging findings almost always enables differentiation from various other disease entities. Follow-up of surgical as well as non-surgical patients is another important role of MRI. Computed tomography (CT) is restricted to pre-surgical workup and to the immediate postoperative period.  相似文献   
743.
Cochlear implants are used worldwide for the treatment of severe to profound bilateral sensorineural hearing loss in both adults and children. A number of implantees are likely to be treated with radiosurgery later in life, but very little is known about the effects of radiosurgery on cochlear implants. We report a cochlear-implanted patient who underwent radiosurgery due to a recurrent meningioma. After radiosurgery, the impedance of the implant maintained a normal range, and auditory performance tests were unchanged as compared to before radiosurgery. This is the first report addressing the effects of radiosurgery in a patient with a cochlear implant.  相似文献   
744.
We aimed to test the hypothesis that brain large artery diameters relate to distal downstream arteriolar diameters. In a sample of 110 autopsied individuals (69% men, 76% HIV+, mean age 51), we used multilevel models to relate large artery lumen and lumen-to-wall ratio to left frontal lobe arteriolar lumen and lumen-to-wall ratio adjusting for demographics and vascular risk factors. Comparing the large artery characteristics of the whole brain did not disclose significant associations with frontal lobe arteriolar characteristics. However, restricting the comparison to large arteries upstream of the studied arterioles demonstrated an independent association between left-sided frontal lobe arteriolar luminal diameter with large artery luminal diameters (B?=?1.82?±?0.77, P?=?0.01) and with large artery lumen-to-wall ratio (B?=?0.58?±?0.29, P?=?0.05). In stratified models, the point estimates in the HIV+ subsample were larger than in the HIV? subsample. These finding suggest coupling between higher proximal blood flow represented by large artery diameter and lower distal resistance represented by arteriolar dilatation. The relationship between arteriolar dilatation and brain parenchyma homeostasis should be further studied.  相似文献   
745.
Autoimmune pancreatitis (AIP) is a rare disease clinically characterized by obstructive jaundice, unintentional weight loss, acute pancreatitis, focal pancreatic mass, and diabetes. AIP is classified into two subtypes - type 1 and type 2 - according to pathological findings, clinical features, and serology test results, but some cases may be defined as type not otherwise in the absence of pathological findings and inflammatory bowel disease. To address the differences in diagnostic criteria by country, standard diagnostic criteria for AIP were proposed in 2011 by an international consensus of expert opinions. Differential diagnosis of AIP from pancreatic ductal adenocarcinoma is important but remains challenging for clinicians. Fortunately, all subtypes of AIP show dramatic response to steroid treatment. This review discusses the current perspectives on the diagnosis and management of AIP in clinical practice.  相似文献   
746.
747.
The initial severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron subvariants, BA.1 and BA.2, are being progressively displaced by BA.5 in many countries. To provide insight on the replacement of BA.2 by BA.5 as the dominant SARS-CoV-2 variant, we performed a comparative analysis of Omicron BA.2.12.1 and BA.5.2 variants in cell culture and hamster models. We found that BA.5.2 exhibited enhanced replicative kinetics over BA.2.12.1 in vitro and in vivo, which is evidenced by the dominant BA.5.2 viral genome detected at different time points, regardless of immune selection pressure with vaccine-induced serum antibodies. Utilizing reverse genetics, we constructed a mutant SARS-CoV-2 carrying spike F486V substitution, which is an uncharacterized mutation that concurrently discriminates Omicron BA.5.2 from BA.2.12.1 variant. We noticed that the 486th residue does not confer viral replication advantage to the virus. We also found that 486V displayed generally reduced immune evasion capacity when compared with its predecessor, 486F. However, the surge of fitness in BA.5.2 over BA.2.12.1 was not due to stand-alone F486V substitution but as a result of the combination of multiple mutations. Our study upholds the urgency for continuous monitoring of SARS-CoV-2 Omicron variants with enhanced replication fitness.  相似文献   
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