血液气体监测与酸碱平衡失常.ppt

单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,血液气体监测与酸碱平衡失常,blood-gas analysis&acid-base disorder,徐州医学院麻醉学院危重病医学教研室,第一部分血气监测参数及临床意义意义,氧分压,Partial Pressure of Oxygen,氧饱和度,Oxygen Saturation,二氧化碳分压,Partial Pressure of Carbon Dioxide,气体交换效率指标,Gas Exchange,氧供与氧耗,Oxygen Delivery and Consumption,酸碱平衡,Acid-base balance,血氧分压,PO,2,PaO,2,PvO,2,PtcO,2,血氧饱和度,SO,2,SaO,2,SpO,2,氧分压与氧饱和度,氧分压,mmHg,氧饱和度,%,10-13,20-35,30-57,40-75,50-83,60-89,70-93,80-95,90-97,100-98,说明：在,10-30mmHg,范围内氧饱和度是顺序排列的奇数；在,40mmHg,处，把,30mmHg,时的“,57”,变成“,75”,；从,50-100mmHg,范围内依次增加的偶数不断减少，仅最后的“,2”,重复一次，末了增加,1,。,二氧化碳分压,PCO,2,PaCO,2,PtcCO,2,P,ET,CO,2,T-CO,2,气体交换效率指标,A-aDO,2,A-aDO,2,/PaO,2,PaO,2,/FiO,2,Qs/Qt,V,D,/V,T,A-aDO,2,（,PB,47,）*,FiO,2,PaCO,2,/R,PaO,2,预计值,0.21*,（年龄,+25,）,Qs/Qt,（,C,C,O,2,CaO,2,）,/,（,C,C,O,2,C,V,O,2,）,A-aDO,2,*0.0031/,（,A-aDO,2,*0.0031+5,）,pH=7.43 PaO,2,=71 PaCO,2,=32 FiO,2,=21%,肺泡气氧分压,=,吸入气氧分压,-PaCO2/R =(760-47),21%-32/0.863 =149-40=109mmHg,肺泡气动脉血氧分压差,=109-71=38mmHg,A-aDO,2,计算方法,氧供与氧耗,C-O,2,DO,2,VO,2,O,2,ER,酸碱平衡分析的主要参数,pH,PaCO,2,HCO,3,BB,、,BE,、,BD,AB,与,SB,AB,SB,：呼吸性酸中毒,CO,2,CO,2,CO2,H,2,O,H,2,CO,3,HCO,3,-,Hbuf,Buf,-,+,H,+,+,H,+,+,AB,AB,SB,和,AB,第二部分血气监测与呼吸生理,外呼吸,气体在血液中的运输,内呼吸,外呼吸与血气监测,肺通气功能,VA,VCO,2,/PCO,2,*K,PaO,2,与,PaCO,2,肺换气功能,A-aDO,2,Qs/Qt,缺氧与低氧血症,肺泡气中的氧与二氧化碳的逆向关系,缺氧,hypoxia,低张性缺氧,Hypotonic,hypoxia,血液性缺氧,Hemic,hypoxia,循环性缺氧,Circulatory,hypoxia,组织性缺氧,Histogenous,hypoxia,各种缺氧的血氧变化,缺氧类型,PaO,2,SaO,2,C-O,2,MAX,CaO,2,CaO,2,C,V,O,2,低张性缺氧,N,或,N,血液性缺氧,N,N,或,N,或,N,循环性缺氧,N,N,N,N,组织性缺氧,N,N,N,N,低氧血症,hypoxemia,PiO,2,过低,肺泡通气不足,弥散功能障碍,肺泡,V/Q,比值失调,低氧血症原因分析,血气变化,A-aDO,2,PaO,2,PaCO,2,吸空气吸纯氧,PiO,2,过低,降低正常 正常 正常,肺泡通气不足,降低增高 正常 正常,V/Q,失调,正常或降低正常 增加 正常,肺内右左分流,降低 降低或正常增加 增加,弥散障碍,降低 正常或增加增加 正常,解剖右左分流,降低 降低或正常增加 增加,气体运输,氧容量,C-O,2MAX,C-O,2MAX,1.38Hb,氧含量,C-O,2,C-O,2,（,1.34HbSaO,2,）,0.00315PO,2,氧供,DO,2,DO,2,CaO,2,CI,氧输送,外呼吸,血液与氧的结合,循环系统输送,氧在组织的释放释放,组织呼吸,P,50,P,V,O,2,S,V,O,2,P,a-V,O,2,氧需求,oxygen demand,氧耗量,VO,2,氧摄取率,ERO,2,oxygen extraction ratio,S,V,O,2,及,P,V,O,2,变化的常见原因,S,V,O,2,P,V,O,2,氧供 氧耗 常见原因,80 44 CO,，左右分流，,FiO,2,，,高压氧，,测量错误，脓毒症，低温，全麻，,肌松，甲减,60,80 31,44,N N CO,正常，,SaO,2,正常，代谢正常,60 chloride,Gastrointestinal losses sodium salt administration(acetate,citrate),Vomiting Massive blood transfusions,Gastric drainage,Parenteral,nutrition,Chloride-wasting diarrhea(villous adenoma)Plasma volume expanders,After diuretic use Sodium lactate(Ringers solution),After,hypercapnea,Other,Chloride unresponsive(urine,Cl,-,20mmol/L,)Severe deficiency of intracellular,cations,Mineralocorticoid,excess Magnesium,potassium,Primary,hyperaldosteronism,(,Conns,syndrome),Secondary,hyperaldosteronism,Cushings,syndrome,Liddles,syndrome,Bartters,syndrome,Exogenous corticoids,Excessive licorice intake,Ongoing diuretic use,From William C,Shoemaker,Stephen M.Ayres,Ale,Grenvik,Peter R,Holbrook:Textbook,of Critical Care,4th Edition,847,Treatment of Metabolic Alkalosis,Primary,aldosteronism,:,Spironolactone,；,Restriction of sodium intake and potassium supplementation,；,Surgery,；,Dexamethasone,is effective in long-term therapy of familial,dexamethasone-responive,aldosteronism,.,Secondary,aldosteronism,:,Angiotensin,-converting enzyme inhibitors,Cushings,syndrome:,Caused by pituitary,oversecretion,of ACTH:surgery or radiation,Caused by adrenal adenoma or carcinoma:,adrenalectomy,Caused by secondary or,ectopic,ACTH production:address the underlying malignancy,Treatment of Metabolic Alkalosis,Liddles,syndrome:,Triamterence,Bartters,syndrome:,Postssium,-sparing diuretics,potassium and magnesium supplementation,angiotensin,-converting enzyme inhibitors,and,cyclooxygenase,inhibitors,Exogenous corticoids:,Discontiunation,of the offending agent or agents and vigorous initial potassium replacement.,Severe potassium or magnesium depletion:,Replacement of these electrolytes(may require very large amounts).,呼吸性酸中毒,respiratory acidosis,Acute respiratory acidosis causes:,CNS suppression,neuromuscular disease or impairment,airway and,parenchymal,lung disease,permissive,hypercapnia,Chronic respiratory acidosis causes:,chronic lung disease,chest wall disease,central,hypoventilation,chronic neuromuscular disease,Treatment of Respiratory Acidosis,Treat the underlying causes,Supplemental Oxygen,Noninvasive/Invasive Ventilation,CO,2,排出综合征,BP,HR,心律失常,甚至心跳停止,.,(1),应激消失,(2),回心血减少,(3),冠状血管,脑血管收缩,心脑供血不足,.,overventilation,to chronic,hypercapnia,has two undesirable consequences:,life-threatening,alkalemia,difficulty to,wean,the patient from mechanical ventilation.,慢性呼酸治疗就注意的几个问题,一般不需应用碱性药物纠正酸血症,避免过多给氧,避免应用镇静药物,综合治疗,呼吸中枢兴奋剂一般无效,黄体酮可能有效,机械通气,呼吸性碱中毒,Respiratory Alkalosis,reside at high altitude,pathologic conditions:,salicylate,intoxication,early sepsis,hepatic failure,hypoxic,respiratory disorders,pregnancy,pain or anxiety,Hypocapnia,appears to be a particularly bad prognostic indicator in patients with critical illness.,Treatment of Respiratory Alkalosis,Treat the underlying causes,Nacrotics,Mechanical ventilation,Supplemental Oxygen,复习思考题,1,、反映气体交换效率的指标,2,、反映氧供需平衡的指标,3,、常见的低氧血症的原因,4,、氧合指数的计算,5,、主要的酸碱平衡调节机制,6,、代偿的时间、极限、最大幅度,7,、酸碱平衡失常的诊断,8,、酸碱平衡失常的治疗原则,谢谢,二七年九月十一日,