Case discussion

SC 陳賢璟

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

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

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 expan

ded. 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

3 things that should be avoided during the induction of anesthesia

Light Anesthesia Abrupt Decreases In Systemic

Vascular Resistance Drugs That Release Histamine

Several goals related to the maintenance of anesthesia (1) Define the severity of the disease: Pulmo

nary 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

Several goals related to the maintenance of anesthesia (2) Avoid changes in right ventricular preloa

d: Maintain adequate preload but do not overhydrate

Maintain right ventricular contractility: Avoid negative inotropes, consider inotropic support in light of ventricular dysfunction

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

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

Isoflurane (2) Systemic vascular resistance : produc

e dose dependent decreases in systemic vascular resistance.

Pulmonary vascular resistance : decrease pulmonary vascular resistance and blunt the Hypoxic Pulmonary Vasoconstriction Reflex (HPV).

Isoflurane (3) Coronary blood flow : Isoflurane is kn

own 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

Case report When compared with pre-induction baseli

ne 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

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

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

Background (2) Early surgical intervention, early mobilizatio

n, 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

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

Hypothesis

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

Patients (1)

Age > 60 years old With CAD (as indicated by previous myocardial i

nfarction, 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)

Patients (2) Excluded from the study : in the presence of contraindications to epid

ural analgesia1. known allergy to any of the study drugs 2. acute coronary insufficiency 3. electrocardiographic evidence of left bun

dle branch block 4. 10 h or more from the time of injury

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

Procedures (2) Epidural analgesia : an epidural catheter was inserted into the lumbar e

pidural 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

Result (1)-Trial Profile

Result (2)

Result (3)

Primary Outcomes: Preoperative Period(1)

Primary Outcomes: Preoperative Period(2)

Primary Outcomes: Preoperative Period(3)

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

Secondary Outcomes: Postoperative

Period

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)

Discussion Mechanism ? Stress response: may enhance perioperative hypercoagulabl

e 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

Discussion (2)

Anticoagulants: low-molecular-weight heparin prophy

laxis regimen Increase the risk of spinal hematoma The epidural catheter should be remo

ved not less than12 h after the last dosing of enoxaparin.

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.