The Development of Apoptosis and DNA Fragmentation in Transient Ischemic Model in Rats, and Roles of Dexamethasoneand Hypothermia / 대한마취과학회지

BACKGROUND: Neuronal cell death after brain ischemia occurs predominately by necrosis, whereas only a minor fraction of cell death may occur through apoptosis. Authors investigated DNA fragmentation and apoptotic morphology in the brain cell to determine whether apoptosis contributes to the progression of an ischmic lesion. This study was conducted to determine the effects of dexamethasone and hypothermia on moderate brain ischemic injury by middle cerebral artery occlusion (MCAO) in rats. METHODS: Thirty Sprague-Dawley rats (220 - 280 g) were used. Anesthesia was induced and maintained with isoflurane in oxygen. MCAO was induced by intraluminal monofilament nylon. All rats were divided randomly into three groups. In group I (n = 10), normal saline 1 ml was injected intravenously 10 minutes before MCAO. In group II (n = 10), dexamethasone 3 mg/kg was administered and in group III (n = 10), body temperature was maintained at 32degreesC. After 60 minutes of MCAO, all rats that recovered from anesthesia were returned to cages. After 24 hour reperfusion, brain tissue was quickly removed and cerebral hemispheres were separated. Lesion volumes were measured by TTC staining. TUNEL reactivity was examined in the cortical infarction lesion, and rat brain DNA was run on agarose gel electrophoresis to detect DNA fragmentation. RESULTS: Apoptosis and DNA fragmentation in the nucleus developed in the hippocampal area after transient ischemia in rats. Dexamethasone did not prevent the development of apoptosis and DNA fragmentation in transient brain ischemic rats. Moderate hypothermia could prevent the development of apoptosis and DNA fragmentation in transient brain ischemic rat. CONCLUSIONS: Apoptosis may represent a mode of ischemic cell death, and dexamethasone couldn't prevent apoptotic change in the ischemic brain insult. Moderate hypothermia (32degreesC) was a specifically effective procedure to reduce the development of apoptotic change in ischemic insults.

A Comparison of the Efficacy and Safety of Tropisetron and Tropisetron Plus Dexamethasone as Antiemetics for Elective Thyroidectomy / 대한마취과학회지

BACKGROUND: Thyroidectomy is associated with a relatively high incidence of postoperative nausea and vomiting (PONV) ranging from 63% to 84%. In this study, we evaluated the safety and the antiemetic effects of tropisetron 30 microgram/kg or tropisetron 30 microgram/kg plus dexamethasone 5 mg in patients undergoing thyroidectomy under a standard anesthetic technique without narcotics. METHODS: Sixty-eight patients undergoing thyroidectomy were randomized to receive a placebo (Group C, n = 28), tropisetron 30 microgram/kg (Group T, n = 23) or tropisetron 30 microgram/kg plus dexamethasone 5 mg (Group T + D, n = 17) IV over 2 5 minutes immediately before the induction of anesthesia. The effects of these regimens on the development of PONV, adverse events and need for rescue antiemetics were analyzed for the 0 to 1 hour and 1 to 24 hours postoperative periods. RESULTS: In the 0 to 1 hour postoperative periods, the incidence of PONV in group C, T and T + D was 35.7%, 17.4% and 17.6% respectively, which showed no significant difference among the three groups (P > 0.05). In the same period, the incidence of retching or vomiting in Group C, T and T + D was 14.3%, 0% and 0% respectively, which showed a significantly lower incidence in Group T and T + D than Group C (P 0.05). During the first 24 hours postoperatively, the overall incidences of PONV was 67.9% for group C, 60.9% for group T and 58.8% for group T + D, which showed no siginificant difference among the three groups (P > 0.05). Group T + D patients had more headache compared to other groups, but there was no significant difference in theincidences of overall adverse events. CONCLUSIONS: Neither tropisetron or tropisetron plus dexamethasone was significantly different from the placebo for the prevention of PONV after thyroidectomy during the first 24 hour postoperative period. Only vomiting during the first 1 hour postoperatively was prevented in the tropisetron and combination of tropisetron plus dexamethasone groups compared to the control group.

The Effects of Dexamethasone and MK-801 on Edema Formation in Middle Cerebral Artery Occlusion Model of the Rat / 대한마취과학회지

BACKGROUND: This study was conducted to determine the effects of dexamethasone and MK-801 on the formation of brain edema resulting from a focal ischemic injury by middle cerebral artery occlusion in rats. METHODS: Fifteen Sprague-Dawley rats (220 280 g) were freely allowed to drink and eat until just before surgery. Anesthesia was induced with 4% isoflurane in oxygen and then maintained with 2% isoflurane in oxygen. Ischemic injury was induced by an intraluminal suture with a blunted tip inserted into the internal carotid artery and occlusion of the middle cerebral artery. All rats were divided randomly into three groups. In group I (n = 5), normal saline 1 ml was injected intravenously 10 minutes before MCA occlusion. In group II (n = 5), dexamethasone 3 mg/kg was administered 10 minutes before injury. In group III (n = 5), a N-methyl-D-aspartate receptor antagonist, MK-801 1 mg/kg was injected 30 minutes before injury. Rectal temperatures were monitored during the experiment. After 60 minutes of MCA occlusion, the intraluminal sutures were removed and all the rats were returned to their cages. Their brain were quickly removed and the cerebral hemispheres were sepaerated into ischemic cores and penumbra zones after 1 hour of reperfusion. The separated cerebral hemispheres were dried 7 days at 60oC dry oven. The cerebral water content was assessed by the dry-weight method. RESULTS: In the dexamethasone group, there were no significant changes in cerebral edema formation in both ischemic core and the penumbra. In the MK-801 group, there were significant reductions in the brain edema formation in the penumbra (P< 0.05), but not in the core. CONCLUSIONS: Dexamethasone has no effect on ischemic brain edema; however, MK-801 is effective in the ischemic penumbra zone by reducing of edema formation.

Dexamethasone Treatment of Bone Pain in Metastatic Prostate Cancer: Assessment of Pain Indices and Quality of Life / 대한마취과학회지

BACKGROUND: Steroid therapy has been considered as co-analgesic for palliative treatment of metastatic bone pain in terminal cancer. We designed prospective study to observe analgesic efficacy of dexamethasone, to evaluate different analgesic assessment methods and its correlation to actual improvement of quality of life. METHODS: Thirty seven men with symptomatic bone pain of prostate cancer were treated with dexamethasone infusions (10mg twice a day) for 2 weeks. Response to treatment was assessed by daily analgesic intake, by the McGill-Melzack pain questionnaire (MPQ), and by a series of 17 linear analog self-assessment scales (LASA) relating to pain and to various aspects of quality of life. Biochemical and radiological markers were measured. RESULTS: Fourteen patients (38%) had improvement in indices used to assess pain at 2 weeks after starting dexamethasone. Reduction in pain indices was associated with improvement in other dimensions of quality of life and in the scale for overall well-being. Even though radiological and biochemical markers showed no correlation, symptomatic relief of pain was associated with a decrease in serum concentration of adrenal androgens. CONCLUSION:g We conclude that 1) dexamethasone treatment may cause useful relief of pain in some of patients with bone pain of prostate cancer; 2) this relief of pain is associated with suppression of adrenal androgens; 3) measures of pain and quality of life can be used to assess benefits of systemic therapy with dexamethasone; and 4) this effects of dexamethasone should be further investigated in bone pain of other metastatic cancer.

Effects of Aprotinin and Insulin on Regulation of Inducible Nitric Oxide Synthase m-RNA in the Mouse Macrophage / 대한마취과학회지

BACKGROUND: Nitric oxide (NO) has been known to have antimicrobial activity, and the increased NO production in case of sepsis may play as a physiologic defense mechanism. However the increased formation of NO by the inducible nitric oxide synthase (iNOS) has been known to be implicated in pathophysiology of a variety of disease, including circulatory and septic shock. We measured the iNOS activities of mouse macrophage after application of various drugs with lipopolysaccharide (LPS) and gamma-interferon (IFN). The purpose of this study is to evaluate the inhibiting properties of various drugs to iNOS in case of sepsis. METHOD: Thirty ICR (Institue for Cancer Research) mouse weighting 30~40 gm were anesthetized with diethyl ether, and thiogycol broth was injected into peritoneal cavity. Two days later macrophages were collected from peritoneal cavity, and incubated for 24 hours in the CO2 incubator with LPS and IFN mixture and various concentration of dexamethasone, pentoxifylline, aspirin, aprotinin, regular insulin (RI) and neutral protamine hagedorn insulin (NPH). NO concentration were calculating by measuring nitrite concentration which represent the magnitude of NO production. The activities of iNOS in macrophages were measured by analysing iNOS m-RNA expression by Northern blot analysis with autoradiography using polymerase chain reaction (PCR) method. RESULT: The basic NO concentration was 13.0 +/- 8.0 micrometer. With LPS and IFN, NO concentration was increased to 104.4 +/- 31.9 micrometer. The increase in NO production by LPS and IFN was attenuated by dexamethasone (10 (-6) M only), pentoxifylline (above 10 (-10) M), aprotinin, RI, and NPH in dose dependent manner. The addition of LPS and IFN in the culture media caused increase in the iNOS m-RNA production. The aprotinin, RI, and NPH attenuated the increase in iNOS m-RNA production by LPS and IFN. Coclusion: These results suggest that the aprotinin, RI, and NPH prevent the LPS and IFN induced increase of NO production by attenuating the iNOS activity. These properties of aprotinin and insulin may be applied to the treatment of septic shock to block the enhanced formation of NO production.

Effect of Epidural Dexamethasone Injection for Back Pain after Lumbar Epidural Anesthesia / 대한마취과학회지

Background: Lumbar epidural anesthesia is widely used regional blockade method. But postepidural back pain is most common cause that experienced patients refuse epidural anesthesia. We planned this study to evaluate the effect of epidural dexamethasone injection for postepidural back pain. Methods: Adult patients free of back pain were randomly allocated into two groups. In both group anesthesia was induced with 2% lidocaine 20~25 ml mixed with 1:200,00 epinephrine and fentanyl 0.1 mg. After surgery, epidural catheter was removed after epidural dexamethasone injection in one group (group 2). In other group (group 1), catheter was removed without treatment. We visited patients and asked existence of back pain, and the intensity of back pain was measured by visual analogue scale at 24, 48 and 72 hours after surgery. Statistical analysis was done by Student's t-test and Mann-Whitney test. Results: In group 2, there was significant decrease in number of patients suffering from back pain and intensity of back pain. Conclusion: Epidural dexamethasone injection results in decreased number of patients suffering from back pain and also less in intensity of back pain.

Do Metoclopramide with Dexamethasone Act Synergistically in Control of Postoperative Nausea and Vomiting? / 대한마취과학회지

BACKGROUND: Better effect of antiemetic drugs can be obtained by combination of multiple antiemetic drugs that have different mechanisms of action. However, if the combined drugs have similar mechanisms of action, the incidence of side effects may be increase. This study was conducted to evaluate the ability of using combination therapy consisting of metoclopramide and dexamethasone in control of postoperative nausea and vomiting. METHODS: Sixty adult female patients undergoing major gynecological operation under the general anesthesia were randomly divided into two groups according to administered drugs. The patients received a single IV dose of metoclopramide (10 mg, Group I) or metoclopramide plus dexamethasone (10 mg 8 mg, Group II) when as operator sutured the skin wound. The incidences of nausea and vomiting were assessed during the first 12, 24, and 48 hours after recovery from anesthesia. RESULTS: There were no prominent incidences of postoperative nausea and vomiting between two groups within postoperative 12 hours. But there were significantly increased incidences of nausea and vomiting in Group I (26.7%, 13.3%) compared to Group II ( 8.0%, 3.2%) during postoperative 24 hours and 48 hours. CONCLUSIONS: Combination therapy of metoclopramide with dexamethasone seemes to have no synergic effect in control of postoperative nausea and vomiting.