الفهرس 
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Abstract
Inadequate pain relief during, and particularly after, surgery is associated with the release of proinflammatory cytokines, hypercoagulability, and overactivity of several neuroendocrine systems. In the presence of a compromised coronary circulation; this stress response may lead to a temporary mismatch between myocardial oxygen supply and demand and, possibly, to myocardial ischemia.
Perioperative myocardial ischemia is the single most important predictor of poor cardiac outcome, defined as myocardial infarction, unstable angina, and sudden death, in patients who have, or are at high risk for coronary artery disease (CAD).
Much of perioperative myocardial ischemia has been described as being asymptomatic and not associated with increased levels of traditional serum markers of myocardial injury, such as CK-MB fractions or cardiac troponins. Brain natriuretic peptide (BNP) hormone is one member of the natriuretic peptides which are produced by the heart and regulate arterial blood pressure, electrolyte balance, and fluid volume as they act as counter regulatory hormones to the increased sympathoadrenal and neurohormonal activation in response to ischemic myocardial injury.
BNP is now reported to be the biochemical marker of choice for evaluating the acute risk of nonsurgical patients with cardiovascular conditions ranging from asymptomatic myocardial ischemia without ST segment elevation to acute transmural myocardial infarction.
NT-proBNP is the biologically inactive part due to cleavage of the prohormone proBNP to active BNP and inactive NT-proBNP. Also, it is stable in the blood for longer time than the biologically active BNP. So, it is preferable to measure the NT-proBNP as an indicator of left ventricular dysfunction and ischemia.
The aim of this study was to compare the effect of three analgesic techniques used during hip haemiarthroplastic surgery for patients who are at risk for, or had, ischemic heart disease as regards hemodynamic stability, incidence of ischemia, pain control and incidence of complications.
This study was carried out on 60 adult patients undergoing hip hemiarthroplasty. These 60 patients had documented CAD or risk factors for CAD. They were divided into 3 equal groups (20 patients for each group). The grouping of the patients were according to integration of analgesia during the perioperative period which is parentral opioids (Group I) or integration of lumbar epidural opioids (Group II) and integration of lumbar epidural local anesthetics with opioids in addition to general anesthesia in the three groups in order to investigate whether supplemental LEA during hip hemiarthroplasty in patients who are at risk for, or had, CAD would attenuate their plasma concentrations of NT-proBNP and cardiac troponin I (cTnI).
The comparative study has been done as regarding to:
1- Patient’s characteristics (Age, weight, sex, cardiac risk factors).
2- Vital signs during the perioperative period (heart rate, mean arterial blood pressure, oxygen saturation and CVP measurement).
3- ECG detected ST segment changes during the perioperative period.
4- Evaluation of postoperative pain score and total doses of additional analgesics.
5- Evaluation of postoperative complications in each group (respiratory depression, nausea, pruritus, vomiting, hemodynamic instability and neurologic manifestation).
6- Evaluation of plasma levels of cardiac biomarkers (NT-proBNP, cTnI, s. cortisol, s. norepinephrine) changes during the perioperative period.
This study showed that integration of epidural analgesia by local anesthetic with opioids in group III resulted in more stable hemodynamics (heart rate and mean arterial blood pressure) during the perioperative period with no significant influence on CVP measurement and arterial oxygen saturation when compared to the epidural opioids alone (group II) and the balanced general anesthesia group (group I).
This study showed no significant difference between LEA groups and balanced general anesthesia group as regards perioperative ECG changes. This study revealed also that LEA with local anesthetic and opioid is superior to LEA with opioid alone which was in turn superior to parenteral opioids in the postoperative analgesia. It was associated with better VAS value and less consumption of additional analgesia.
This study revealed also that integration of LEA to general anesthesia was safer whether by opioids alone or by local anesthetic with opioids than the use of the balanced general anesthesia alone in the term of occurrence of postoperative complications such as nausea, vomiting and pruritus, while there were no statistical significant intergroup differences as regards the occurrence of hemodynamic instability and neurologic manifestations.
This study also confirmed the anti-ischemic effect of LEA, where it results in less significant increase in NT-proBNP concentrations during the perioperative period especially with local anesthetic and opioids when compared to the parenteral analgesic group with no influence on cTnI plasma concentrations in the three groups.
Also, LEA results in significant lower levels of s. cortisol and s. norepinephrine levels for 48hs postoperatively by local anesthetic with opioids when compared to increased levels after only 24hs with LEA by opioids alone and immediate increased levels postoperatively after ICU admition in the parenteral analgesic group.
from this study, it is concluded that epidural analgesia concomitant with general anesthesia by opioids with local anesthetics is a good choice for hip hemiarthroplasty in ischemic heart patients that it is accompanied with less postoperative complication, more stable hemodynamics and less neuroendocrinal stress response. Also, NT-proBNP is a marker of choice for detecting subclinical myocardial ischemia during perioperative periods.
It is recommended to use lumbar epidural analgesia by local anesthetic with opioids when general anesthesia is selected for ischemic heart disease patients undergoing hip hemiarthroplasty, not to depend on ECG alone intraoperatively for detection of myocardial ischemia and use NT-proBNP routinely in the perioperative period of ischemic heart patients.