102例危重病患者有创血压和无创血压的对比

目的比较102例危重病患者有创血压（IBP）和无创血压（NBP）测量结果的一致性。 方法收集2016年3~9月在西安交通大学第二附属医院重症医学科住院治疗的102例危重病患者的尺/桡动脉IBP和同侧上臂NBP数据1072对,先对所有数据分别按收缩压、舒张压、脉压（PP）和平均动脉压（MAP）进行配对t检验;再将数据分为高血压组（MAP≥107 mmHg）（1 mmHg=0.133 kPa）、正常血压组（70 mmHg≤MAP<107 mmHg）和低血压组（MAP<70 mmHg）三个亚组,分别进行IBP和NBP的收缩压、舒张压、PP以及MAP间的配对t检验。以P<0.05为差异具有统计学意义。 结果有创收缩压和无创收缩压之间比较,差异具有统计学意义［（128.08±35.48）mmHg vs（122.56±24.84）mmHg,t=7.896,P<0.001）］;有创舒张压和无创舒张压之间比较,差异具有统计学意义［（65.66±13.69）mmHg vs（67.98±13.31）mmHg,t=-8.294,P<0.001］;有创PP和无创PP之间比较,差异具有统计学意义［（62.42±28.93）mmHg vs（54.58±20.00）mmHg,t=11.697,P<0.001］;有创MAP和无创MAP之间比较,差异无统计学意义［（86.47±18.94）mmHg vs（86.17±15.33）mmHg,t=0.867,P=0.386］。亚组分析显示高血压组（n=254）：有创收缩压和无创收缩压之间比较,差异具有统计学意义［（163.75±33.93）mmHg vs（152.16±16.78）mmHg,t=6.52,P<0.001］,有创舒张压和无创舒张压之间比较,差异具有统计学意义［（79.17±11.03）mmHg vs（83.69±9.50）mmHg,t=-6.85,P<0.001）］,有创PP和无创PP之间比较,差异具有统计学意义［（84.57±31.50）mmHg vs （68.47±20.72）mmHg,t=9.76,P<0.001］;正常血压组（n=687）：有创收缩压和无创收缩压之间比较,差异具有统计学意义［（122.66±24.74）mmHg vs（118.70±15.14）mmHg,t=5.071,P<0.001）］,有创舒张压和无创舒张压之间比较,差异具有统计学意义［（63.97±10.34）mmHg vs（65.60±8.49）mmHg,t=-5.049,P<0.001）］,有创PP和无创PP之间比较,差异具有统计学意义［（58.69±23.05）mmHg vs （53.10±11.90）mmHg,t=7.682,P<0.001］;低血压组（n=131）：有创收缩压和无创收缩压之间比较,差异无统计学意义［（87.35±24.33）mmHg vs（85.41±11.99）mmHg,t=1.109,P=0.269］,有创舒张压和无创舒张压之间比较,差异具有统计学意义［（48.32±8.27）mmHg vs（49.98±8.06）mmHg,t=-2.073,P=0.040］,有创PP和无创PP之间比较,差异具有统计学意义［（39.03±24.00）mmHg vs（35.43±13.97）mmHg,t=1.806,P<0.001］。 结论有创收缩压大于无创收缩压、有创舒张压小于无创舒张压、有创PP大于无创PP,而有创MAP等于无创MAP。采用MAP数值较采用收缩压和（或）舒张压数值可以消除IBP和NBP测量之间的差异。     

Intervention studies to reduce the prevalence and incidence of pressure sores: a literature review

Much has been written about the prevention of pressure sores. However, electronic and manual searches located only 10 studies within the literature in the UK that described interventions able to reduce either their incidence or prevalence. All the studies located contained serious methodological flaws. Apparent success in reducing the number or severity of pressure sores could have resulted because staff involved in data collection were aware that the study was being undertaken and thus took more interest in pressure area care. From the review findings it is apparent that there is a dearth of research evidence upon which to base practice in the sphere of pressure sore prevention and further research is urgently required.     

Hemodilution does not alter the aortic-to-femoral arterial pressure difference in dogs

Introduction.Distal arterial pressure normally differs from aorticpressure. This difference is modified by changes of vascular resistance.Hemodilution, due to decreased viscosity, decreases vascular resistance.Therefore, the difference between aortic and distal arterial pressures couldbe altered as well. We investigated whether acute hemodilution affected thisdifference in dogs. Methods.Eleven mongrel dogs weighing 16.6 ±4.4 kg were anesthetized with pentobarbital and sufentanyl and mechanicallyventilated. Arterial presssure was recorded using Millar catheter-tippedpressure transducers in the proximal aorta and in the distal femoral artery.An electromagnetic flowmeter probe was placed around the aorta. Effectivedownstream pressure was estimated by extrapolation of exponential arterialpressure decay during 3-second occlusion of the proximal aorta. Hemodilutionwas effected by removal of 30 ml/kg of blood and replacement with 60 ml/kg ofwarmed saline. In addition, the effects of 1 µg/kg phenylephrine and 4µg/kg of sodium nitroprusside were measured before and afterhemodilution. Results.Hemodilution decreased hematocrit from 39± 11.2% to 25.6 ± 4.95%. Systolic and mean pressures wereunchanged but aortic diastolic pressure decreased significantly, from 86± 17 to 79 ± 15 mmHg (p < 0.005). Peak systolicpressure was 13.5 ± 7.2 mmHg higher in the femoral artery than in theaorta before, and 16 ± 8.7 mmHg after, hemodilution (p >0.05). Nitroprusside decreased the femoral to aortic peak systolic pressuredifference from 14.3 ± 6.3 to 7.7 ± 15.3 mmHg, p = 0.05before hemodilution and from 14.3 ± 8.8 to 2.5 ± 11 mmHg,p < 0.005 afterwards. Hemodilution significantly decreased theeffective downstream pressure, from 44 ± 9 to 36 ± 6.8 mmHg inthe aorta (p< 0.05), and from 51 ± 2 to 37 ± 3.1mmHg in the distal femoral artery (p< 0.05). Conclusion.Acute hemodilution did not alter the aortic-to-distal arterial pressuredifference in dogs.     

血浆胶体渗透压对危重症患者预后的意义

目的 分别对危重症患者血浆胶体渗透压、总渗透压与预后的关系进行研究,探讨其与危重症患者预后的关系.方法 回顾性分析2002年1月至2005年12月入住首都医科大学附属北京朝阳医院急诊重症监护病房(EICU)与外科监护病房(SICU)的1568例患者,依据其入院时的血浆胶体渗透压与总渗透压的测定值分别进行分组,计算其病死率,并且进行X2统计学检验比较.血浆胶体渗透压以20 mmHg(即1.2mOsm/kgH2O)为界分为两组;总渗透压以280 mOsm/kgH2O与310 mOsm/kgH2O为界分为三组.结果 低胶体渗透压组与正常胶体渗透压组患者相比病死率高(24.5% vs.17.7%,P=0.001);而在总渗透压的分析中,低渗透压组与正常渗透压组患者相比病死率低(17.0%vs.24.5%,P=0.000).结论 危重症患者血浆胶体渗透压较总渗透压与预后的关系更为密切,可作为一个危重症患者预后的判断指标,危重症患者维持正常血浆胶体渗透压应当引起重视.     

A comparative study of the cardiorespiratory effects of continuous positive airway pressure breathing and continuous positive pressure ventilation in acute respiratory failure

Positive end expiratory pressure (PEEP) produces cardiopulmonary effects whether administered by controlled positive pressure ventilation (CPPV) or continuous positive airway pressure (CPAP). In eight patients with acute respiratory failure, the effects of 20 cm PEEP administered via CPPV and CPAP were compared. An esophageal balloon was used to calculate the transmural vascular pressures. The control values under mechanical ventilation with no PEEP (IPPV) for PaO₂ and QS/QT (FiO₂ being 1.0) were respectively 132±15 mmHg and 31±3%; CPPV gave a PaO₂ of 369±27 mmHg and QS/QT fo 14±1.6%, CPAP 365±18 mmHg and 18±1.3% respectively. The two different modes of ventilation (CPPV and CPAP) gave identical blood gas improvement through the same level of end expiratory transpulmonary pressure despite marked differences between absolute mean airway and esophageal pressures. Conversely, hemodynamic tolerance was very different from one technique to the other: CPPV depressed cardiac index from 3.4±0.3 to 2.4±0.2 l/min/m² as well as decreasing transmural filling pressures, suggesting a reduction in venous return. Conversely, filling pressures maintained at control values during CPAP and cardiac indexes were unchanged.Abbreviations IPPV intermittent positive pressure ventilation; mechanical ventilation (controlled mode) with zero end expiratory pressure (ZEEP) - CPPV continuous positive pressure ventilation: mechanical ventilation (controlled mode) with a positive pressure during expiration - CPAP continuous positive airway pressure; spontaneous ventilation with a positive pressure maintained during expiration - PEEP positive end expiratory pressure, whatever the ventilatory mode; spontaneous (CPAP) or mechanical (CPPV) Presented in part at the 44 th annual meeting of American College of Chest Physicians, Washington DC, October 1978     

不同体位对经膀胱内途径间接测定腹内压影响的研究

目的 观察不同体位下经膀胱内途径间接测定腹内压的影响.方法 对2006～2008年本院ICU收治的48例腹内压增高的患者按IAP高低分级经膀胱间接测定腹内压.其中IAP Ⅰ级10例,IAPⅡ级18例,IAPⅢ级12例,IAPⅣ级8例.分别取平卧位、15°、30°、45°四种不同体位下观察腹内压的变化情况.结果 体位改变使患者腹内压数值发生改变,特别是45°体位时更为明显.结论 对于经膀胱内途径间接测定腹内压时要采取平卧位才使监测数据更具准确性和客观性.

Abstract：

Objective To investigate different patients'body positions influenced the intra-abdominal pressure. Methods There were 48 patients with intra-abdominal hypertension (IAH) from years of 2006 to 2008 in ICU. According to the value, the intra-abdominal pressures were ranked them four grades as four groups also: Ⅰ (10 cases), Ⅱ (18 cases), Ⅲ (12 cases), Ⅳ (8 cases). Every patient's intra-abdominal pressures were measured under 4 different body positions: prostration, elevations of 0° , 15°, 30°, 45°corresponding respective group. Results The value of intra-abdominal pressures were changed as position's variance, especially under elevations of 45 °.Conclusions In order to get precise and objective data of intra-abdominal pressure, patients'position should be prostration.     

Comparison of intracranial pressure measured simultaneously within the brain parenchyma and cerebral ventricles

We report a 48-year-old man treated for acute subarachnoid hemorrhage (SAH) wherein intracranial pressure (ICP) was measured simultaneously within the ventricular cerebrospinal fluid (CSF) and the brain parenchyma (PAR). Single pressure waves within the continuous pressure signal were identified with determination of the single wave parameters pulse amplitude (i.e. pressure difference between diastolic minimum pressure and systolic maximum pressure), mean pressure (i.e. mean pressure from beginning to ending minimum diastolic minimum pressure), and latency (i.e. rise time from diastolic minimum pressure to systolic maximum pressure). A total of 218,589 CSF/PAR single pressure wave pairs were analyzed. For these CSF/PAR wave pairs the mean difference in pulse pressure amplitude was −0.13 mmHg [95% confidence interval (CI) −0.13 to −0.12 mmHg], mean difference in mean single wave pressure −0.71 mmHg (95% CI −0.74 to −0.68 mmHg), and mean difference in latency −0.01 seconds (95% CI −0.01 to −0.01 seconds). Hence, in this patient monitoring ICP within the ventricular CSF or brain parenchyma gave similar results. Moreover, the comparisons of single CSF/PAR wave pulse pressure amplitudes gave no evidence of a pressure gradient from brain parenchyma to the ventricular CSF in this patient.Brean A, Eide PK, Stubhaug A. Comparison of intracranial pressure measured simultaneously within the brain parenchyma and cerebral ventricles.     

有创血压预测方法探讨

目的 探讨有创血压的预测方法. 方法 47例受试者接受示波法测量肱动脉无创血压,桡动脉置管测量有创血压,血管超声技术检测颈总动脉和桡动脉的结构和血流动力学参数.采用线性回归方法建立有创血压预测方程;典型相关分析方法筛选有创血压预测的潜在参数. 结果 有创收缩压多元线性回归方程为Y=17.21-64.357X1+2.80X2+1.324X3(y为有创收缩压,X1为桡动脉阻力指数,X2为桡动脉搏 动指数,X3为无创收缩压);与反映有创血压的典型变量较为密切的无创测量指标有无创血压、颈动脉血管壁剪切率、桡动脉阻力指数和搏动指数、颈动脉收缩期峰值流速. 结论 有创血压可以通过无创血压及血流动力学参数进行预测.除无创收缩压和桡动脉阻力指数之外,潜在参数还包括无创舒张压、桡动脉搏动指数、颈动脉血管壁剪切率、颈动脉收缩期峰值流速.     

Noninvasive continuous blood pressure measurement: A clinical evaluation of the Cortronic APM 770

The Cortronic APM 770 (Cortronic, Ronkonkoma, NY) is a commercial device that claims to measure blood pressure noninvasively and continuously with the use of a standard blood pressure cuff. The aim of our study was to assess the performance of the continuous-mode blood pressure readings of the Cortronic during anesthesia and surgery. We recorded blood pressure in 5 patients bilaterally. An intraarterial pressure (IAP) curve was recorded from 1 arm and the Cortronic pressure curve (CPC) was recorded from the other. For statistical analysis the period between 2 Cortronic recalibrations was defined as the intercalibration interval. The duration of these intervals ranged from 20 to 0.5 minutes. Four paired samples were drawn from each interval. The first sample in an interval represented the recalibration blood pressure; the other samples represented the continuous blood pressure. A total of 1,232 samples were taken, of which 308 were recalibration. The median of the differences and the 2.5th and 97.5th percentile limits of agreement were determined. Their respective values for diastolic and systolic recalibration measurements were 5, –17, and 34 mm Hg, and 6, –12, and 38 mm Hg. Their values for continuous measurements were 4, –23.5, and 32 mm Hg, and 6, –30, and 70 mm Hg. Changes in CPC were evaluated against changes in the corresponding IAP by plotting them in 4-quadrant graphs. In these graphs the Spearman rank correlations were betweenr=–0.17 andr=0.01. We observed opposite CPC and IAP trends on 24 occasions during this study. We performed a simple simulation study to better understand the measurement method of the Cortronic. The study showed a positive relationship between pulsation volume and CPC amplitude, and between pulsation rate and CPC amplitude. We conclude that during anesthesia and surgery continuous-mode blood pressure readings of the Cortronic are unreliable, and suggest that the phenomenon of the two pressures' moving in opposite directions is inherent to the measurement principles of the device.     

机械通气患者呼气末正压对膀胱压的影响

目的：探讨机械通气患者呼气末正压（PEEP）对膀胱压的影响。方法选取我院重症医学科机械通气且监测膀胱压的患者40例,将膀胱压正常＜1．47 kPa（15 cmH2 O）的患者23例作为A组,膀胱压增高≥1．47 kPa （15 cm H2 O ）的患者17例作为 B 组,采用自身对照法,观察患者在断开呼吸机及使用呼气末正压0 kPa （0 cmH2O）、0．294 kPa （3 cmH2O）、0．490 kPa（5 cmH2O）、0．981 kPa（10 cmH2O）和1．47 kPa（15 cmH2O）时的膀胱压变化。结果A组患者在不同呼气末正压时膀胱压的变化差异无统计学意义（P＞0．05）。B组患者在呼气末正压＞0．294 kPa（3 cmH2 O）时随着呼气末正压的增高膀胱压也会随之增高,差异有统计学意义（P＜0．05）,呼气末正压为≤0．294 kPa（3 cmH2 O）时与断开呼吸机时测得的膀胱压比较,差异无统计学意义（P＞0．05）。结论膀胱压＜1．47 kPa（15 cm H2 O ）时,可保持呼吸机的呼气末正压正常调整,以保证患者的氧合,保障患者的安全。膀胱压≥1．47 kPa（15 cmH2 O）时,应保持呼吸机的呼气末正压≤0．294 kPa（3 cmH2 O）的水平,以保证患者的氧合,保障患者的安全。