腹腔高压症及腹腔压力监测在危重病人中的应用

腹腔高压症及腹腔压力监测,彭 沪,背景,19世纪后期，Eddy1890年，Heinricius1951年，Baggot1984年，Kron,Results from the International Conference of Experts on Intra-Abdominal Hypertension (IAH) and Abdominal Compartment Syndrome (ACS),DEFINITIONSIntensive Care Medicine 2006; 32:1722-1732,INTRODUCTION TO THE DEFINITIONS,Intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) have been increasingly recognized in the critically ill as causes of significant morbidity and mortality.The variety of previous definitions has led to confusion and difficulty in comparing one study to another.An international group of critical care specialists convened to standardize definitions for both IAH and ACS as well as establish standards for the measurement of intra-abdominal pressure (IAP).,WHAT IS INTRA-ABDOMINAL PRESSURE?,Elevated IAP is a common finding in the ICUIAP increases and decreases with respirationIAP is directly affected by:Solid organ or hollow viscera volumeSpace occupying lesionsAscites, blood, fluid, tumorsConditions that limit expansion of the abdominal wallBurn eschars, third-space edema,,WHAT IS ABDOMINAL PERFUSION PRESSURE?,“Abdominal perfusion pressure (APP) = mean arterial pressure (MAP) minus intra-abdominal pressure (IAP) = MAP - IAP.”The critical IAP that leads to organ failure varies by patientA single threshold IAP cannot be globally applied to all patientsAnalogous to cerebral perfusion pressure, APP assesses not only the severity of IAP, but also the relative adequacy of abdominal blood flowAPP is superior to IAP, arterial pH, base deficit, and arterial lactate in predicting organ failure and patient outcomeFailure to maintain APP 60 mmHg by day 3 predicts survival,,HOW SHOULD IAP BE MEASURED?,“IAP should be expressed in mmHg and measured at end-expiration in the complete supine position after ensuring that abdominal muscle contractions are absent and with the transducer zeroed at the level of the midaxillary line.”Physical exam is inaccurate in predicting IAPSensitivity 40-61%Positive predictive value 45-76%IAP measurements are essential to the diagnosis of elevated IAP and the management of IAHA variety of techniques may be used to measure IAP,,WHAT IS THE REFERENCE STANDARD FOR IAP?,“The reference standard for intermittent IAP measurement is via the bladder with a maximal instillation volume of 25ml sterile saline.”,,WHAT IS NORMAL IAP?,“Normal IAP is approximately 5-7 mmHg in critically ill adults.”,,WHAT IS INTRA-ABDOMINAL HYPERTENSION?,“IAH is defined by a sustained or repeated pathological elevation in IAP 12mmHg.”The definition of IAH has varied over the years with thresholds as high as 40 mmHg being previously advocated.Most clinicians are therefore concerned only when IAP exceeds 20-25 mmHgThis is well above the IAP that can cause organ dysfunction and failure Failure to intervene when IAP rises above 25 mmHg is associated with poorer outcome,,HOW IS IAH GRADED?,“IAH is graded as follows: Grade IIAP 12 - 15 mmHgGrade IIIAP 16 - 20 mmHgGrade III IAP 21 - 25 mmHgGrade IV IAP 25mmHg.”The IAH grades have been revised downward as the detrimental impact of elevated IAP on end-organ function has been recognized,,WHAT IS ABDOMINAL COMPARTMENT SYNDROME?,“ACS is defined as a sustained IAP 20mmHg (with or without an APP =20 mm Hg *出现一个或多个脏器功能衰竭,*Malbrain M L; Deeren D; De Potter, et al. .Current opinion in Critical Care. 2005,11(2):156-171 .,IAH/ACS 表现,特征性变化 腹胀心输出量（CO）下降肺顺应性下降，气道峰压(Ppeak)急剧升高少尿或无尿,病因及流行病学,病因及流行病学,The higher the IAP, the poorer the survival rate,Malbrain ML, Chiumello D, Pelosi P, et al. CCM, 2005, 33(2) :315-322,预测病人死亡率的独立危险因素年龄APACHE收入ICU类型有无肝功能不全ICU期间发生IAH入院第一日IAP12mmHg APP(腹腔灌注压)=MAP-IAP,Malbrain ML, Chiumello D, Pelosi P, et al. CCM, 2005, 33(2) :315-322,病因及流行病学,*Cheatham ML, White MW, Sagraves SG, et al. J Trauma 2000; 49:621-626.,病因及流行病学,IAH独立预测因素（independent predictors）肝功能不全腹部手术液体复苏肠麻痹-高度警惕IAH的发生！,Malbrain ML, Chiumello D, Pelosi P, et al. CCM, 2005, 33(2) :315-322,IAP监测方法,腹腔压力测定,经膀胱测压法,间接测压法,直接测压法,下腔静脉压,经胃测压法,经直肠测压法,穿刺直接测压,经腹引管测压,膀胱内压力测定方法 （urinary bladder pressure, UBP）Kron等在1984年提出并推广应用。 原理：膀胱内有50100ml液体时膀胱壁会象膈肌一样反映IAP的变化。,IAP监测方法,IAP监测方法,股静脉/下腔静脉压力测定方法经股静脉（或下腔静脉）插管测定下腔静脉压力与腹内压力变化以及经腹腔直接测定、经膀胱压力测定结果有较好的相关性 股静脉及下腔静脉血流与IAP呈负相关性改变，即虽着IAP增高而降低,IAP监测方法,胃内压力测定方法经鼻胃管向胃内注入50-100ml生理盐水，连接传感器或压力计，以腋中线为零点进行测量。,IAP监测方法,患者取仰卧位，适当镇静与肌松，镇静与肌松的程度以能消除腹肌收缩为标准，留置导尿，排空膀胱内尿液。将导尿管与连有500ml生理盐水的输液皮条连接，往导尿管内持续滴注注射约25ml生理盐水。将输液皮条拔出生理盐水袋，静置30 60秒，在以腋中线为0点，测量皮条内液体高度，读取呼气末数值，即为腹内压值。,循环系统,ACS and MODS,胸腔内压力静脉回心血量外周血管阻力,IAP机械性压迫,心输出量,下腔静脉、门静脉和腹膜后静脉血流减少膈肌升高，下腔静脉发生扭曲、狭窄,ACS and MODS,循环系统IAP为2025mmHg时，出现CO/CI明显下降，HR增快， BP降低，CVP仍升高IAH 增加对前负荷评估的难度CVP?CO?,Alexander Schachtrupp, Juergen Graf, Christian Tons, et al. J Trauma. 003;55:734 740.,ACS and MODS 循环系统,CVP升高,心输出量(CO)下降,Alexander Schachtrupp, Juergen Graf, Christian Tons, et al. J Trauma. 2003;55:734 740.,ACS and MODS 循环系统,胸腔内血流量(ITBV)降低,总循环血量(TCBV)降低,Alexander Schachtrupp, Juergen Graf, Christian Tons, et al. J Trauma. 2003;55:734 740.,ACS and MODS 循环系统,CO 与 ITBV,CO 与 CVP,ACS and MODS,呼吸系统最早和显著的临床表现。Ppeak升高，肺顺应性下降，P/F下降，高碳酸血症。,ACS and MODS,呼吸系统呼吸系统总静态顺应性PV 曲线变平并右移IAP 升高时，IAP与PV曲线下拐点呈正相关关系。肺中性粒细胞激活，肺脏炎性渗出增加 肺泡水肿及压缩性肺不张,Malbrain ML, Deeren D, Nieuwendijk R, et al. Intensive Care Med 2003; 29:S85.,Alexander Schachtrupp, Juergen Graf, Christian Tons, et al. J Trauma. 2003;55:734 740.,ACS and MODS 呼吸系统,ACS and MODS,主动脉和肾动脉受压，肾脏毛细血管网阻力升高，肾静脉回流受阻输尿管受压,IAP机械性压迫,肾动脉的灌注血量减少， 肾皮质的血流分流到髓质，致使肾小球的有效滤过率下降，尿的生成减少,肾功能FG(肾脏滤过压)=MAP-2IAP,ACS and MODS,肾功能少尿，Cr, BUN, CCr 肾素、醛固酮、ADH,Alexander Schachtrupp, Juergen Graf, Christian Tons, et al. J Trauma. 2003;55:734 740.,ACS and MODS 肾功能,尿量减少,ACS and MODS -肾功能,Balogh, Z, McKinley BA, Holcomb JB. Trauma, 2003, 54(5):848-861,ACS and MODS -肾功能,Lindstrm P, Wadstrm J, Ollerstam A, et al. Nephrology Dialysis Transplantation, 2003, 18(11):2269-2277.,胃肠道 大量动物实验证实小肠血流量与IAH有关，IAP 升至10 mmHg，胃肠道灌注减少细菌移位 内脏受压，内脏缺血。研究显示IAH刺激促炎介质的释放门静脉及中心静脉细胞因子水平显著升高 肠道喂养困难,Friedlander MH, Simon RJ, Ivatury R, et al. J Trauma 1998; 45:433-489.,ACS and MODS,腹腔压力（IAP）监测与EN,神经系统 IAP25mmHg时出现ICP-颅内压力升高，与IAP成正相关。CPP-脑灌注压降低，CPP=MAP-ICP胸腔内压和CVP增高使脑组织静脉血回流受阻，颅内血管床扩大所致CPP下降，颅内损害加重头部创伤病人应谨慎使用腹腔镜诊治，并应监测IAP,ACS and MODS,Deeren D, Leijs J, Van den Brande E, et al. Crit Care Med in press.,ACS and MODS 神经系统,颅内压(ICP)与IAP,Joseph DA, Dutton RP, Aarabi B, et al. Trauma, 2004,57(4):687-695.,腹腔减压术前后参数改变,外科重症病人IAP改变的临床观察,* UBP25cmH2O为IAH组，UBP25c