高血压英文ppt精品课件anesthetic management of the patient with

Anesthetic Management of the Patient with Preeclampsia Dmitry Portnoy, MD Anesthesiology Department MATERNAL MORTALITY IN PREGNANCY IN THE UNITED STATES, 1980-1985 CAUSE RATE (%) Embolism 17.0 Indirect causes 15.6 Hypertension in pregnancy 12.3 Ectopic pregnancy complications 10.0 Hemorrhage 9.1 Stroke 8.4 Anesthesia 7.0 Complications of termination 5.2 Cardiomyopathy 4.2 Infection 3.5 Other 7.7 Adapted from the US Maternal mortality Surveillance, 1980-1985. MMWR CDC Surveillance Summary, 1988 . Classification of Hypertensive Disease in Pregnancy (Australian Society for the Study of Hypertension in Pregnancy, 1999) Risk Factors and Mechanisms of Preeclampsia Risk of preeclampsia up to 8% of all pregnancies Factors implicated in increased risk of developing preeclampsia l Genetic determination, familial history l Chronic HTN, DM, chronic renal disease, LSE, sickle cell l Twin gestation, nulliparity, maternal age over 40, adolescents Pathogenesis of preeclampsia is poorly understood l multisystem abnormalities - only in the presence of placental tissue l generalized endothelial cell disorder l excessive immunologic reaction Triad of physiological derangements l Intense vasospasm endothelium, platelets, trophoblasts l Local or disseminated intravascular coagulation l Plasma volume contraction disruption FACTORS THAT DIFFERENTIATE MILD FROM SEVERE PREECLAMPSIA Mild Severe Systolic arterial pressure 500 mL24 hr 500 mL/24 hr Headache no yes Visual disturbances no yes Epigastric pain no yes Right upper quadrant abdominal pain no yes Pulmonary edema no yes Cyanosis no yes HELLP no yes Platelet count 100,000/mm3 50%) Thrombocytopenia Disseminated intravascular coagulation Clinical placental abruption FETAL Fetal distress Intrauterine growth retardation Modified from Gallery EDM: Hypertension in pregnancy. Practical management recommendations. Drugs 1995;49:4:561. Pre-anesthetic Evaluation Assessment of target organ-system involvement l CV: HTN control, LV function, intravascular depletion l Renal: degree of oliguria, creatinine level l Liver: LFTs, signs of liver capsule streching l Coagulation profile: platelet count, PT, PTT l Airway examination: degree of laryngeal edema Anesthetic risk factors l Poorly controlled hypertension l 2+ urinary protein, elevated serum uric acid l Thrombocytopenia less than 75,000 l Central vascular volume depletion l Association with chronic HTN and IDDM Invasive Monitoring Arterial catheter l Sustained diastolic blood pressure greater than 90 mm Hg l Use of parenteral vasodilaters (NTP, NTG) l Induction of anesthesia with potential rapid BP fluctuations l Inability to obtain accurate BP by cuff l Need for frequent sampling Pulmonary artery catheter l Severe HTN unresponsive to conventional treatment l Severe pulmonary edema l Persistent oliguria unresponsive to fluid challenge Regional Anesthesia for Preeclamptic Patient Advantages of epidural anesthesia l Blunts hormonal and hemodynamic responses l Provides better hemodynamic stability l Increases renal and uteroplacental blood flow l Decrease potential for seizures Spinal anesthesia l Growing evidence of safety in preeclampsia l Less hemodynamic stability (?) l Less potential for hematoma Combined spinal-epidural Thrombocytopenia and Epidural Block Safe lower limit for platelet count before epidural Retrospective analysis of 2929 parturients (Rasmus, 1989) l 14 with platelet count 18,000 90,000 received neuraxial block l None had sequelae of spinal hematoma l No spinal/epidural hematomas in parturients reported Low-dose aspirin and neuraxial block apparently safe Bleeding time questionable indicator of risk of RA Recommendations l Patient history, signs of bleeding, test tube clot formation, ACT l Modification of technique that decreased the risk of bleeding ? General Anesthesia for Preeclamptic Patient Airway edema l Attention to hoarseness, high pitched or stridorous voice l Small ETT (5-6 mm) Hypertensive response l Induction, intubation and extubation l HTN and tachycardia can lead to increased ICP Interaction of anesthetic agents with magnesium sulfate HELLP Syndrome H E L L P Occurs in 4-12% of severe PIH patients Reported perinatal mortality: 7.7- 60% Maternal mortality 3.5- 24.2%. emolisis elevated iver ow latelets Eclampsia From Gr., a fancied perception of flashes of light Occurrence of a seizure that is not attributable to other causes in a preeclamptic patient Steps in managing an eclamptic convulsion: l Maintain adequate oxygenation l Prevent maternal injury during the convulsion l Minimize the risk of aspiration l Give adequate magnesium sulfate to control the convulsions l Maternal acidemia should be corrected l Do not attempt to shorten or abolish the initial convulsion l Avoid polypharmacy Conclusion Preeclampsia is fairly common multisystem disorder Associated with high maternal and perinatal M&M. (Mortality in obstetric patient can be 200%!) Important steps in anesthesia ma