Case discussion

1. Case discussion SC 陳賢璟

2. Cardiac echo report (2003-4-1) • LVEF=0.66 • Good LV contractility • LV concentric hypertrophy • Dilated LA, RA • MS, PR: moderate • TR: moderate-severe • Pulmonary hypertension

3. Secondary pulmonary hypertension • Elevations in resistance to pulmonary venous drainage • Increased resistance to flow through the pulmonary vascular bed • Increased resistance to flow through large pulmonary arteries • Hypoventilation

4. The goals related to the pre-anesthetic management • Elective procedures should be postponed until all of the reversible components of pulmonary hypertension, cor pulmonale, and other co-existing conditions are treated. • Eliminate and control acute or chronic infections of the airway. • Reverse or treat bronchospasm. • Make sure that poorly ventilated or collapsed alveoli are fully expanded. • Provide adequate hydration. • Assess... Activity tolerance Arterial oxygenation and gas exchange Electrocardiogram Chest xray Consider the need for pulmonary function testing, echocardiogram, and stress testing

5. 3 things that should be avoided during the induction of anesthesia • Light Anesthesia • Abrupt Decreases In Systemic Vascular Resistance • Drugs That Release Histamine

6. Several goals related to the maintenance of anesthesia (1) • Define the severity of the disease: Pulmonary artery catheters and arterial lines are often necessary to determine monitor vascular function and titrate drug therapy • Avoid treatable increases in PA pressure such as: Hypoxia, Hypercarbia, Acidosis, Hypothermia, Nitrous Oxide, Alpha-adrenergic drugs, High airway pressure, PEEP

7. Several goals related to the maintenance of anesthesia (2) • Avoid changes in right ventricular preload: Maintain adequate preload but do not overhydrate • Maintain right ventricular contractility: Avoid negative inotropes, consider inotropic support in light of ventricular dysfunction

8. Several goals related to the maintenance of anesthesia (3) • Maintain left ventricular afterload: Spinal anesthesia should be avoided due to rapid onset of sympathetic blockade. Epidural anesthesia can be considered but should be used cautiously. Pulmonary vasodilators such as sodium nitroprusside, nitroglycerin, and epoprostenol administration may also result in excessive decreases in systemic vascular resistance

9. Isoflurane (1) • Blood pressure : produce a dose-dependent decrease in blood pressure (mainly result from a decrease in systemic vascular resistance ) • Heart rate : produce a dose-dependent increase in heart rate • Cardiac performance : do not significantly alter cardiac output

10. Isoflurane (2) • Systemic vascular resistance : produce dose dependent decreases in systemic vascular resistance. • Pulmonary vascular resistance : decrease pulmonary vascular resistance and blunt the Hypoxic Pulmonary Vasoconstriction Reflex (HPV).

11. Isoflurane (3) • Coronary blood flow : Isoflurane is known to be a potent coronary artery vasodilator. Isoflurane induced coronary artery vasodilatation can lead to redistribution of coronary blood flow away from diseased areas to areas with normal responsive coronary arteries. This phenomenon is called the coronary steal syndrome

12. Case report • When compared with pre-induction baseline variables, isoflurane 1% with 100% oxygen and atracurium caused a 60% decrease in PVR accompanied by 24% decrease in PAP, a 19% decrease in SVR accompanied by a 17% decrease in arterial blood pressure, and an increase in cardiac output of 21%. Reference：Isoflurane and primary pulmonary hypertension, D. C. H. CHENG AND G. EDELIST, Anaesthesia, 1988, Volume 43, pages 22-24

13. Preoperative Cardiac Events in Elderly Patients with Hip Fracture Randomized to Epidural or Conventional Analgesia Matot I. Oppenheim-Eden A. Ratrot R. Baranova J. Davidson E. Eylon S. Peyser A. Liebergall M. Preoperative cardiac events in elderly patients with hip fracture randomized to epidural or conventional analgesia. [Clinical Trial. Journal Article. Randomized Controlled Trial] Anesthesiology. 98(1):156-63, 2003 Jan

14. Background (1) • The overall incidence of perioperative myocardial ischemia in elderly patients undergoing hip fracture surgery has been reported to be 35–42% • The principal causes of in-hospital death after hip fracture : CHF & MI : 2 days after hip fracture Bronchopneumonia : the majority of late deaths Pulmonary embolism : the second week after injury

15. Background (2) • Early surgical intervention, early mobilization, antibiotics, and prophylactic anticoagulation reduced death from bronchopneumonia and pulmonary embolism after hip fracture • Prevention of perioperative cardiac morbidity and mortality- modulating sympathetic response : β-blockers α2-agonists

16. Epidural analgesia • In recent years, epidural analgesia has been shown to exert a favorable effect on the stress response • In addition to providing sympatholysis, local anesthetics also relieve pain, which is a potent trigger for the stress response

17. Hypothesis • The use of epidural analgesia during the stressful presurgical period would decrease the incidence of adverse cardiac events in patients with fractured hips

18. Patients (1) • Age > 60 years old • With CAD(as indicated by previous myocardial infarction, typical angina, atypical angina with positive stress test results, or angiographic or scintigraphic evidence of CAD) • At high risk for CAD(the patient had at least two of the following cardiac risk factors: age >= 65, hypertension, current smoking, serum cholesterol level > 240 mg/dl, and diabetes mellitus)

19. Patients (2) • Excluded from the study : in the presence of contraindications to epidural analgesia • known allergy to any of the study drugs • acute coronary insufficiency • electrocardiographic evidence of left bundle branch block • 10 h or more from the time of injury

20. Procedures (1) • All patients in both groups received oxygen by nasal cannulae (7 l/min), and preoperative fluid administration was monitored • Conventional analgesia: 1 mg/kg intramuscular meperidine every 6 h, oral or intramuscular dipyrone was given when pain relief was inadequate

21. Procedures (2) • Epidural analgesia : an epidural catheter was inserted into the lumbar epidural space at the L2–L3 or L3–L4 interspace. A 3-ml test dose of 2% lidocaine with epinephrine (1:200,000) was then administered. Pain relief was provided with 4 mg methadone and 7–10 ml bupivacaine, 0.25%, followed by a continuous epidural infusion of 16 mg methadone and 45 mg bupivacaine (0.5%) over 24 h. Epidural bupivacaine (0.25%, 5 ml) was administered when pain relief was inadequate

22. Result (1)-Trial Profile

23. Result (2)

24. Result (3)

25. Primary Outcomes: Preoperative Period(1)

26. Primary Outcomes: Preoperative Period(2)

27. Primary Outcomes: Preoperative Period(3)

28. Primary Outcomes: Preoperative Period(4) Pain scores in the preoperative period. Pain scores were determined by a visual analog scale (VAS) graded from 0 (no pain) to 100 mm. Measurement times: 1 = before administration of analgesia; 2 = 1 h after administration of analgesia; 3 = before surgery. A = at rest; B= while the patient was slightly moving the fractured leg. *P < 0.05 between groups

29. Secondary Outcomes: Postoperative Period

30. Secondary Outcomes: Postoperative Period • intraoperative factor (blood loss, volume of fluid administered) • postoperative factor (supplement of oxygen, fluid management, mobilization) • anesthetic factor (technique, drugs, dose)

31. Discussion • Mechanism ? • Stress response: may enhance perioperative hypercoagulable state and the release of cytokines and neuroendocrine hormones, which may dispose to vascular thrombosis and cardiac morbidity through reductions in myocardial oxygen supply or increases in demand

32. Discussion (2) • Anticoagulants: low-molecular-weight heparin prophylaxis regimen • Increase the risk of spinal hematoma • The epidural catheter should be removed not less than12 h after the last dosing of enoxaparin.

33. Discussion (3) • The number of the observed events were few and the study groups were relatively small • Long-term outcome • The relationship between epidural analgesia, stress response to hip fracture, and adverse cardiac events.