Thenar oxygen saturation and invasive oxygen delivery measurements in critically ill patients in early septic shock

This prospective study was aimed to test the hypothesis that tissue hemoglobin oxygen saturation (StO?) measured noninvasively using near-infrared spectroscopy is a reliable indicator of global oxygen delivery (DO?) measured invasively using a pulmonary artery catheter (PAC) in patients with septic shock. The study setting was a 26-bed medical-surgical intensive care unit at a university hospital. Subjects were adult patients in septic shock who required PAC hemodynamic monitoring for resuscitation. Interventions included transient ischemic challenge on the forearm. After blood pressure normalization, hemodynamic and oximetric PAC variables and, simultaneously, steady-state StO? and its changes from ischemic challenge (deoxygenation and reoxygenation rates) were measured. Fifteen patients were studied. All the patients had a mean arterial pressure above 65 mmHg. The DO? index (iDO?) range in the studied population was 215 to 674 mL O?/min per m. The mean mixed venous oxygen saturation value was 61% ± 10%, mean cardiac index was 3.4 ± 0.9 L/min per m, and blood lactate level was 4.6 ± 2.7 mmol/L. Steady-state StO? significantly correlated with iDO?, arterial and venous O? content, and O? extraction ratio. A StO? cutoff value of 75% predicted iDO? below 450, with a sensitivity of 0.9 and a specificity of 0.9. In patients in septic shock and normalized MAP, low StO? reflects extremely low iDO?. Steady-state StO? does not correlate with moderately low iDO?, indicating poor sensitivity of StO? to rule out hypoperfusion.     

经皮氧分压监测在脓毒性休克患者中的临床应用

脓毒症和脓毒性休克是ICU患者最常见的死亡原因之一。液体治疗是治疗脓毒性休克的重要手段之一,如何进行液体治疗仍然存在很大争议,目前普遍以容量反应性来指导液体治疗。但也有学者发现,即使宏观血流动力学恢复,微循环仍可能存在障碍。休克的本质是微循环障碍,如何监测微循环状况及利用微循环监测对脓毒性休克患者进行早期诊断、病情评估,以及指导液体治疗可能是今后研究的方向。经皮氧分压（TcPO₂）监测技术是通过无创方法将皮肤表面电极加热来估测组织氧分压的技术手段。越来越多的学者研究发现TcPO₂在监测脓毒症和脓毒性休克患者局部组织灌注不足、预测患者预后、指导液体治疗等方面有重要的临床价值。因此本文对TcPO₂在脓毒性休克中的应用进行整理和总结。     

Clinical integrated ultrasound of the thorax including causes of shock in nontraumatic critically ill patients. A practical approach

A rapid identification of the causes of hemodynamic instability or cardiac arrest is crucial for correct treatment. In a critical care setting, ultrasound seems to be an ideal tool for a rapid diagnosis. A multiple-goal problem-based approach represents the main peculiarity of emergency ultrasound and may be considered an extension of physical examination. The integration of data that can rapidly be obtained from the heart, lung, inferior vena cava, abdomen and leg vein examination are often essential for the diagnosis and treatment in critically ill patients. The role and potentiality of integrated ultrasound in cardiac arrest, shock/hypotension and severe dyspnea are considered in this article.     

全心舒张末期容积预测脓毒性休克液体反应性的意义

目的 探讨全心舒张末容最(GEDV)能否作为一项反映心脏前负荷并预测液体反应性的指标,以指导脓毒性休克患者的容量复苏.方法 前瞻性地对南京大学医学院附属鼓楼医院2005年11月至2006年11月的12例脓毒性休克患者纳入研究后立即给予容量复苏共33次,容量复苏的方法为贺斯500 ml/30 min静脉滴注,ITBVI＞850 ml/m2为复苏终点,其他干预措施相同.分别于复苏前和复苏后通过脉搏指示剂连续心排量(PiCCO)监测全心舒张末容量指数(GEDVI)、中心静脉压(CVP)、平均动脉压(MAP)、心脏指数(CI)、每搏输出量指数(SVI)、体循环阻力指数(SVRI)等血流动力学指标,比较容量复苏前后血流动力学指标的变化和相关性.并根据SVI的变化是否大于15%分为容量复苏有反应组和无反应组,比较两组的GEDVI.血液动力学参数前后比较应用非参数检验,相关性分析采用斯皮尔曼等级相关分析.结果 容量复苏后MAP、CI、GEDVI、SVI、CVP较复苏前明显升高[(88.18+8.56和(76.64+6.55),(3.86+0.94)和(2.93+0.71),(737.45+124.23)和(618.82+90.36),(61.92+14.05)和(46.79+15.61),(16.45+6.35)和(12.27+5.82)],分别为P=0.04,P=0.03,P=0.01,P=0.02,P=0.04,SVRI降低[(1418.45+443.91)和(1896.82+759.23)],且差异具有统计学意义(P=0.03);GEDVI变化与SVI和CI的变化呈正相关,r=0.767,r=0.724;而CVP和PAWP与SVI相关性差,r=-0.148,r=～0.314;GEDVI的变化与复苏前GEDVI呈负相关,r=-0.595,容量复苏有反应者复苏前GEDVI相对较低,但差异无统计学意义(P＞0.05).结论 与中心静脉压等压力指标相比全心舒张末容量能够更好地反映脓毒性休克患者心脏前负荷,并可预测液体反应性.     

Venous oxygen saturation and lactate gradient from superior vena cava to pulmonary artery in patients with septic shock

Monitoring of central venous oxygen saturation (ScvO2) is considered comparable with mixed venous oxygen saturation (SvO2) in the initial resuscitation phase of septic shock. Our aim was to assess their agreement in septic shock in the intensive care unit setting and the effect of a potential difference in a computed parameter, namely, oxygen consumption (VO2). In addition, we sought for a central venous to pulmonary artery (PA) lactate gradient. We enrolled 37 patients with septic shock who were receiving noradrenaline infusions, and their attending physicians had placed a PA catheter for fluid management. Blood samples were drawn in succession from the superior vena cava, right atrium (RA), right ventricle, and PA. Hemodynamic and treatment parameters were monitored, and data were compared by correlation and Bland-Altman analysis. Mixed venous oxygen saturation was lower than ScvO2 (70.2% +/- 11.4% vs. 78.6% +/- 10.2%; P < 0.001), with a bias of -8.45% and 95% limits of agreement ranging from -20.23% to 3.33%. This difference correlated significantly to the noradrenaline infusion rate and the oxygen consumption and extraction ratio. These lower SvO2 values resulted in computed VO2v higher than the VO2cv (P < 0.001), with a bias of 104.97 mL min(-1) and 95% limits of agreement from -4.12 to 214.07 mL min(-1). Finally, lactate concentration was higher in the superior vena cava and RA than in the PA (2.42 +/- 3.15 and 2.35 +/- 3.16 vs. 2.17 +/- 3.19 mM; P < 0.01 for both comparisons). Thus, our data suggest that ScvO2 and SvO2 are not equivalent in intensive care unit patients with septic shock. Additionally, the substitution of ScvO2 for SvO2 in the calculation of VO2 produces unacceptably large errors. Finally, the decrease in lactate between RA and PA may support the hypothesis that the mixing of RA and coronary sinus blood is at least partially responsible for the difference between ScvO2 and SvO2.     

Mesenteric lymph from rats subjected to trauma-hemorrhagic shock are injurious to rat pulmonary microvascular endothelial cells as well as human umbilical vein endothelial cells

Previously, we have documented that gut-derived lymph from rats subjected to trauma/hemorrhagic shock (T/HS) is injurious to human umbilical vein endothelial cells (HUVEC). To verify these findings in an all rat systems, the ability of T/HS lymph to increase rat pulmonary microvascular endothelial cell (RPMVEC) monolayer permeability and kill RPMVEC was compared with that observed with HUVECs. RPMVEcs isolated from male rats or HUVECs were grown in 24-well plates for the cytotoxicity assays or on permeable filters in a two-chamber system for permeability assays. Mesenteric lymph was collected from male rats subjected to trauma (laparotomy) plus hemorrhagic shock (T/HS group) or to a laparotomy plus sham-shock (T/SS group). The T/HS group had their mean arterial pressure decreased to 30 mmHg and kept there for 90 min. Lymph samples centrifuged to remove the cellular component were incubated with the RPMVECs or HUVECs at a 10% concentration. Neither T/SS lymph nor post-T/HS portal vein plasma was toxic to or increased the permeability of the RPMVECs or HUVECs. The pattern of cytotoxicity observed in the HUVECs incubated with T/HS mesenteric lymph was similar to that observed in the RPMVECs, as reflected by trypan blue dye exclusion, with more than 95% of the HUVECs and RPMVECs being killed after a 16-h incubation with T/HS mesenteric lymph. However, at earlier time points the amount of LDH released from the HUVEC cells incubated with T/HS lymph was greater than that observed with the PRMVEC, although trypan blue dye exclusion was similar. Similarly, incubation with 10% T/HS lymph increased the permeability of both HUVEC and RPMVEC monolayers more than 2-fold, even with an incubation period as short as 1 h. In conclusion, these results provide further evidence that T/HS lymph, but not T/SS lymph or post-T/HS portal vein plasma, is injurious to endothelial cells and that RPMVECs are as susceptible to injury as HUVECs. Additionally, these studies support the emerging concept that gut-induced distant organ injury is mediated by factors contained in mesenteric lymph.     

Clinical utility of midodrine and methylene blue as catecholamine-sparing agents in intensive care unit patients with shock

Shock is common in the intensive care unit, affecting up to one third of patients. Treatment of shock is centered upon managing hypotension and ensuring adequate perfusion via administration of fluids and catecholamine vasopressors. Due to the risks associated with catecholamine vasopressors, interest has grown in using catecholamine-sparing agents such as midodrine and methylene blue. Midodrine is an orally administered alpha-1 adrenergic agonist while methylene blue is an intravenously administered blue dye used to restore vascular tone and increase blood pressure. Separate MEDLINE, Scopus, and Embase database searches were conducted to assess literature revolving around these agents. Examples of search terms included “midodrine”, “methylene blue”, “critically ill”, “shock”, and “catecholamine-sparing.” Several studies have evaluated their use in patients with shock and found potential benefits in terms of causing significant elevations in blood pressure and hastening catecholamine vasopressor discontinuation with few adverse effects; however, robust evidence is lacking for these off-label indications. Because of the variety of dosing strategies used and the incongruences between patient populations, it is also challenging to define finite recommendations. This review aims to summarize current evidence for the use of midodrine and methylene blue as catecholamine-sparing agents in critically ill patients with resolving or refractory shock.     

Intracellular delivery of liposome-encapsulated prolidase in cultured fibroblasts from prolidase-deficient patients.

Prolidase is a cytosolic exopeptidase whose deficiency causes the development of a rare autosomal recessive disorder known as Prolidase Deficiency (PD). The main manifestations of PD are intractable ulcerations of the skin, recurrent infections and mental retardation. At this time only a hazardous and expensive chronic therapy based on blood transfusions is the suggested treatment for PD. The aim of this work was to investigate the capability of utilizing liposomes as enzyme carriers: these vesicular systems have been recently evaluated as protein carriers for their potential in terms of "in vivo" localization, drug release and for protein stabilization in biological fluids. Liposomes were prepared, with a 1:1 PC:Col molar ratio with or without DSPE-PEG, by a thin-film hydration. Ex-vivo experiments were performed, incubating prolidase loaded liposomes with cultured fibroblasts from PD patients and from controls, to determine the amount of active enzyme delivered to cells. Evaluation of liposomes toxicity on cultured skin fibroblasts showed that liposomes did not interfere with cellular growth. Results showed that all the active prolidase encapsulated in the liposomes was completely vehiculated inside fibroblasts after 6 days incubation. SEM analysis suggests that prolidase is vehiculated inside the cell through liposome endocytosis.     

A microcomputer application for managing information used when weaning patients from mechanical ventilation.

This article describes a microcomputer application designed to manage data collected from patients assessed for weaning from mechanical ventilation. The application has menu options for obtaining individual summaries of serial weaning assessments. These summaries provide an overview of patients' progress during the weaning process. Users also have the option of obtaining information about procedures and problems often encountered during weaning. In addition, weaning summary data are easily transferred to mainframe computers for statistical analyses. The application is an efficient data manager and provides information that can be used during the patient care decision process, for staff and student instruction, and for research purposes.     

Clinical impact of stress dose steroids in patients with septic shock: insights from the PROWESS-Shock trial

IntroductionThe aim of our study was to evaluate the clinical impact of the administration of intravenous steroids, alone or in conjunction with drotrecogin-alfa (activated) (DrotAA), on the outcomes in septic shock patients.MethodsWe performed a sub-study of the PROWESS-Shock trial (septic shock patients who received fluids and vasopressors above a predefined threshold for at least 4 hours were randomized to receive either DrotAA or placebo for 96 hours). A propensity score for the administration of intravenous steroids for septic shock at baseline was constructed using multivariable logistic regression. Cox proportional hazards model using inverse probability of treatment weighting of the propensity score was used to estimate the effect of intravenous steroids, alone or in conjunction with DrotAA, on 28-day and 90-day all-cause mortality.ResultsA total of 1695 patients were enrolled of which 49.5% received intravenous steroids for treatment of septic shock at baseline (DrotAA + steroids N = 436; DrotAA + no steroids N = 414; placebo + steroids N = 403; placebo + no steroids N = 442). The propensity weighted risk of 28-day as well as 90-day mortality in those treated vs. those not treated with steroids did not differ among those randomized to DrotAA vs. placebo (interaction p-value = 0.38 and p = 0.27, respectively) nor was a difference detected within each randomized treatment. Similarly, the course of vasopressor use and cardiovascular SOFA did not appear to be influenced by steroid therapy. In patients with lung infection (N = 744), abdominal infection (N = 510), Gram-positive sepsis (N = 420) and Gram-negative sepsis (N = 461), the propensity weighted risk of 28-day as well as 90-day mortality in those treated vs. those not treated with steroids did not differ among those randomized to DrotAA vs. placebo nor was a difference detected within each randomized treatment.ConclusionsIn the present study of septic shock patients, after adjustment for treatment selection bias, we were unable to find noticeable positive impact from intravenous steroids for treatment of septic shock at baseline either in patients randomized for DrotAA or placebo.

Trial registration

Clinicaltrials.gov {"type":"clinical-trial","attrs":{"text":"NCT00604214","term_id":"NCT00604214"}}NCT00604214. Registered 24 January 2008.     

For better and for worse: Quality of life impaired in HF patients as well as in their partners.

BACKGROUND: Quality of Life (QOL) is known to be impaired in patients with Heart Failure (HF). The involvement of a key person, most often the spouse, enables the HF patient to manage the medical regimen and therefore to sustain Quality of Life (QOL). Yet little is known on the impact of caring for an HF patient on the QOL of the caregiving partner. This study aims to explore the QOL of partners of HF patients compared to the QOL of the patients. METHODS: The study population consisted of 38 couples of hospitalized HF patients and their partners. The Cantril Ladder of Life was used to rate QOL during hospitalization, with regard to the month prior to hospitalization and as projected 3 years in the future. Demographic and clinical variables were collected by patient interview and chart review. RESULTS: On a scale from 0-10, QOL scores of partners varied from 5.9 to 6.4. At some point the QOL score of partners was even lower than the QOL scores of HF patients. In the month prior to hospital admission the QOL of partners was significantly higher in comparison to the QOL of HF patients (6.1 vs. 4.9, respectively). However, this reversed during hospital admission, with QOL scores of partners being significantly lower compared to QOL scores of HF patients (5.9 vs. 6.8, respectively), even after correcting for age and gender. CONCLUSION: In our study the QOL of partners of HF patients was low. Whether this is explicitly due to having to live with a HF patient is not clear. Further research on what partners actually do and the relationship between being a caregiver and QOL is necessary in order to support these partners in giving optimal care and support.     

慢性肝病、肝癌组织中TS,hTERT的表达及其临床意义

目的研究慢性肝病和肝癌组织中胸腺嘧啶合酶 (TS)、人端粒酶反转录酶 (hTERT)表达及其临床病理意义。方法正常肝组织、慢性肝病和肝癌组织标本经 1 0 %中性福尔马林固定后常规制作石蜡包埋切片 ,TS和hTERT染色方法均为常规ABC免疫组化法。结果肝癌病例TS和hTERT阳性率均明显高于正常肝组织、慢性迁延性肝炎、慢性活动性肝炎和肝硬化 ,除肝硬化外均有显著或高度显著差异 (P <0 .0 5或P <0 .0 1 ) ;高分化、淋巴结未转移和肿块最大径≤ 5cm的肝癌其TS ,hTERT阳性率均较明显低于中低分化、淋巴结转移和肿块最大径 >5cm肝癌 ,但两者阳性率与肝癌病理类型及血清HBsAg、AFP状态无明显关系。结论TS或hTERT表达可能是反映肝癌发生发展、生物学行为及预后的重要标记物 ;检测慢性肝病组织中TS ,hTERT表达可能对预防和早期发现肝癌有较重要临床意义