Racial and Socioeconomic Disparities in the Presence of Acute Type A Aortic Dissections

Nonadherence to hypertensive medications is the most common predisposing factor associated with acute aortic dissections. Acute dissections are more likely to occur in African Americans due to higher rates of uncontrolled hypertension. Through a patient case study, the effects of racial and socioeconomic disparities will be illustrated. Through discussing the case of a 39-year-old African American man who presented with hypertensive crisis and nonadherence to hypertension treatment resulting in the diagnosis of an acute aortic dissection. His case exemplifies the effect of health disparities on postoperative outcomes, morbidity, and mortality in the African American population diagnosed with aortic dissections.     

超声引导下腹横肌平面阻滞在腹腔镜下胆囊切除术术后镇痛的疗效与评价

目的 探讨超声引导下腹横肌平面阻滞在腹腔镜下胆囊切除术术后镇痛的疗效与评价。方法 将2018年1月～2019年3月在我院肝胆外科行腹腔镜下胆囊切除术的60例患者随机分为两组,对照组使用气管插管全身麻醉,观察组使用气管插管全身麻醉联合超声引导下腹横肌平面阻滞,比较两组患者术后静息及咳嗽时的疼痛情况、术后镇静程度、不同时间点血压及心率变化、不良反应情况。结果 在静息及咳嗽状态下,观察组出PACU时、术后4 h、术后24 h的VAS疼痛评分均明显低于对照组(P0.05);观察组入PACU后5 min、10 min、15 min的镇静评分低于对照组(P0.05),而入PACU后30 min的镇静评分无明显差异(P0.05);两组在术中及入PACU后各时间点的MAP无明显差异(P0.05),观察组在入PACU 10 min的心率慢于对照组(P0.05),其他时间点无明显差异(P0.05);观察组术后头痛、头晕、嗜睡、恶心呕吐、皮肤瘙痒、颤抖等不良反应发生率与对照组相比无明显差异(P0.05)。结论 超声引导下腹横肌平面阻滞在腹腔镜下胆囊切除术术后镇痛的疗效显著,对血流动力学影响小,安全性高,具有积极的临床意义。     

Expression and effect of sodium-potassium-chloride cotransporter on dorsal root ganglion neurons in a rat model of chronic constriction injury

Sodium-potassium-chloride cotransporter 1 (NKCC1) and potassium-chloride cotransporter 2 (KCC2) are associated with the transmission of peripheral pain.We investigated whether the increase of NKCC1 and KCC2 is associated with peripheral pain transmission in dorsal root ganglion neurons.To this aim,rats with persistent hyperalgesia were randomly divided into four groups.Rats in the control group received no treatment,and the rat sciatic nerve was only exposed in the sham group.Rats in the chronic constriction injury group were established into chronic constriction injury models by ligating sciatic nerve and rats were given bumetanide,an inhibitor of NKCC1,based on chronic constriction injury modeling in the chronic constriction injury + bumetanide group.In the experiment measuring thermal withdrawal latency,bumetanide (15 mg/kg) was intravenously administered.In the patch clamp experiment,bumetanide (10 μg/μL) and acutely isolated dorsal root ganglion neurons (on day 14) were incubated for 1 hour,or bumetanide (5 μg/μL) was intrathecally injected.The Hargreaves test was conducted to detect changes in thermal hyperalgesia in rats.We found that the thermal withdrawal latency of rats was significantly decreased on days 7,14,and 21 after model establishment.After intravenous injection of bumetanide,the reduction in thermal retraction latency caused by model establishment was significantly inhibited.Immunohistochemistry and western blot assay results revealed that the immune response and protein expression of NKCC1 in dorsal root ganglion neurons of the chronic constriction injury group increased significantly on days 7,14,and 21 after model establishment.No immune response or protein expression of KCC2 was observed in dorsal root ganglion neurons before and after model establishment.The Cl^– (chloride ion) fluorescent probe technique was used to evaluate the change of Cl^– concentration in dorsal root ganglion neurons of chronic constriction injury model rats.We found that the relative optical density of N-(ethoxycarbonylmethyl)-6-methoxyquinolinium bromide (a Cl^– fluorescent probe whose fluorescence Cenintensity decreases as Cl– concentration increases) in the dorsal root ganglion neurons of the chronic constriction injury group was significantly decreased on days 7 and 14 after model establishment.The whole-cell patch clamp technique revealed that the resting potential and action potential frequency of dorsal root ganglion neurons increased,and the threshold and rheobase of action potentials decreased in the chronic constriction injury group on day 14 after model establishment.After bumetanide administration,the above indicators were significantly suppressed.These results confirm that CCI can induce abnormal overexpression of NKCC1,thereby increasing the Cl^– concentration in dorsal root ganglion neurons;this then enhances the excitability of dorsal root ganglion neurons and ultimately promotes hyperalgesia and allodynia.In addition,bumetanide can achieve analgesic effects.All experiments were approved by the Institutional Ethics Review Board at the First Affiliated Hospital,College of Medicine,Shihezi University,China on February 22,2017 (approval No.A2017-169-01).     

Dynamic Indicators That Impact the Outcomes of Thoracic Endovascular Aortic Repair in Complicated Type B Aortic Dissection

PurposeTo investigate dynamic variables obtained from retrospective computed tomography angiography for ability to predict thoracic endovascular aortic repair (TEVAR) outcomes in patients with complicated type B aortic dissection (cTBAD).Materials and MethodsSeventy-nine patients with cTBAD who received TEVAR from March 2009 to June 2018 were retrospectively enrolled. Relative true lumen area (r-TLA) was computed at the level of tracheal bifurcation every 5% of all R-R intervals. Parameters that reflect the state of intimal motion were evaluated, including difference between maximum and minimum r-TLA (D-TLA) and true lumen collapse. The endpoints comprised early (≤ 30 days) and late (> 30 days) outcomes after intervention.ResultsOverall early mortality rate was 13.9% (11/79), and early adverse events rate was 24.1% (19/79). Patients who received TEVAR within 2 days of symptom onset demonstrated the worst outcomes. A longer time of r-TLA < 25% in 1 cardiac cycle (P = .049) and larger D-TLA (P < .001) were correlated to an increased early death. In addition, D-TLA was an independent predictor of early mortality. Area under the curve of D-TLA was 0.849 (95% confidence interval 0.730–0.967) for predicting early mortality and 0.742 (95% CI 0.611–0.873) for predicting early adverse events. Survival and event-free survival rates during follow-up were decreased in the D-TLA > 21.5% group compared with the D-TLA ≤ 21.5% group (all P < .001).ConclusionsLarger D-TLA is correlated with worse postoperative outcomes and might be a crucial parameter for future risk stratification in patients with cTBAD.     

Spectrally‐selective measurements of reversible and irreversible transverse relaxation rates from single spin‐echo PRESS acquisitions in muscle

The goal of this study was to test a new formalism for extracting reversible and irreversible transverse relaxation rates from resonances within typical proton muscle spectra using only a single spin echo as acquired with routine single‐voxel, point‐resolved echo spectroscopy (PRESS) acquisitions. Single‐voxel, non‐water‐suppressed PRESS acquisitions within the calf muscles of four healthy subjects were performed at 1.5 T using six echo times ranging from 30 to 576 ms. Novel transverse relaxation analyses of water, choline, creatine, and lipid resonances were performed based upon the disparate relaxation sensitivities of the left versus the right sides of spectroscopically sampled spin echoes. Irreversible and reversible transverse relaxation rates R₂ and R₂′ were extracted for water, metabolites, and lipids using echo times of 288 ms and longer. The R₂ values so obtained were compared with more conventional “gold standard” Hahn values, R_2Hahn, evaluated from the echo‐time dependence of spectral peak areas generated from right‐side sampling alone. Water resonances displayed biexponential Hahn signal decays, consistent with observations of decreasing R₂ values with increasing echo time via the new approach. Choline and creatine resonances displayed monoexponential echo‐time decays, with R_2Hahn values in reasonable agreement with R₂ values obtained from the single‐echo analyses at the longer echo times. Lipid methylene and methyl R₂ values extracted from the new approach were also in reasonable accord with R_2Hahn values. Further validation of the technique was provided through PRESS acquisitions on a water phantom to which various levels of gadolinium were added in order to manipulate transverse relaxation rates, yielding excellent agreement between water‐resonance R_2Hahn and single‐echo R₂ values. In summary, this work demonstrates the feasibility of measuring reversible and irreversible transverse relaxation rates for individual spectral peaks from single‐echo PRESS acquisitions, enabling a reduction in overall scan time relative to the use of multiple acquisitions with varying echo time.