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Feng Xiao

Publications and source records attributed to Feng Xiao.

36 records · Page 2Linked to original sources
PubMed2004

[Impact of intraoperative autotransfusion on RBC's in vivo half-life].

OBJECTIVE: To explore the changes of in vivo half-life of processed erythrocytes following intraoperative autotransfusion(IAT) in off-pump coronary artery bypass grafting(CABG). METHODS: From November 2003 to January 2004,20 consecutive patients undergoing scheduled off-pump CABG were randomly divided into experimental group and control group. Intra-operative autotransfusion was used in the experimental group. The samples were drawn immediately after the saving procedure in the experimental group and immediately after anesthesia introduction through central venous catheter in the control group. A single isotope technique ((51)Cr) was used to determine in vivo half-life of the RBCs in the two groups. RESULTS: There was no significant difference in in vivo half-life between the two groups. CONCLUSION: The in vivo half life of processed erythrocytes following intraoperative autotransfusion ZITI-3000 Cell saving system has not changed significantly in off-pump CABG.

Blood Transfusion, Autologous↗
PubMed2004

Effect of ifenprodil, a polyamine site NMDA receptor antagonist, on brain edema formation following asphyxial cardiac arrest in rats.

OBJECTIVE: Brain edema occurs in experimental and clinical cardiac arrest (CA) and is predictive of a poor neurological outcome. N-Methyl--aspartate (NMDA) receptors contribute to brain edema elicited by focal cerebral ischemia/reperfusion (I/R). Ifenprodil, a NMDA receptor antagonist, attenuates brain edema and injury size in rats after focal cerebral I/R. We assessed the hypothesis that ifenprodil reduces CA-elicited brain edema. METHODS: Eighteen male Sprague-Dawley rats were assigned to group 1 (normal control, n=6), group 2 (placebo-treated CA, n=6), or group 3 (ifenprodil-treated CA, n=6). CA was induced by 8 min of asphyxiation and the animals were resuscitated with cardiopulmonary resuscitation (CPR), ventilation, epinephrine (adrenaline), and sodium bicarbonate (NaHCO3). Ifenprodil of 10 mg/kg or a placebo vehicle was given intraperitoneally 5 min before CA. Brain edema was determined by brain wet-to-dry weight ratio at 1 h after resuscitation. RESULTS: There were no differences between groups 2 and 3 in all physiological variables at baseline. Time from asphyxiation to CA was 201.5 +/- 7.5 s in group 2 and 160.7 +/- 10.4 s in group 3 (P<0.001). Resuscitation time was 68.2 +/- 13.3 s in group 2 and 92.8 +/- 18.2 s in group 3 (P<0.05). Ifenprodil decreased mean arterial pressure (MAP) before asphyxiation, from 128 +/- 7 in group 2 to 82 +/- 15 mmHg in group 3 (P<0.001), and negated immediate post-resuscitation hypertension. Brain wet-to-dry weight ratio was 5.64 +/- 0.44 in group 1, 7.34 +/- 0.95 in group 2 (P<0.01 versus group 1), and 5.93 +/- 0.40 in group 3 (P<0.05 versus group 2). CONCLUSIONS: Ifenprodil reduces CA-elicited brain edema. In addition, we observed significant hemodynamic changes caused by ifenprodil.

Animals↗
PubMed2004

Near-infrared spectroscopy: a tool to monitor cerebral hemodynamic and metabolic changes after cardiac arrest in rats.

INTRODUCTION: Cardiac arrest (CA) is associated with poor neurological outcome and is associated with a poor understanding of the cerebral hemodynamic and metabolic changes. The objective of this study was to determine the applicability of near-infrared spectroscopy (NIRS), to observe the changes in cerebral total hemoglobin (T-Hb) reflecting cerebral blood volume, oxygenation state of Hb, oxidized cytochrome oxidase (Cyto-C), and brain water content following CA. METHODS: Fourteen rats were subjected to normothermic (37.5 degrees C) or hypothermic (34 degrees C) CA induced by 8 min of asphyxiation. Animals were resuscitated with ventilation, cardiopulmonary resuscitation (CPR), and epinephrine (adrenaline). Hypothermia was induced before CA. NIRS was applied to the animal head to measure T-Hb with a wavelength of 808 nm (n = 10) and oxygenated/deoxygenated Hb, Cyto-C, and brain water content with wavelengths of 620-1120 nm (n = 4). RESULTS: There were no technical difficulties in applying NIRS to the animal, and the signals were strong and consistent. Normothermic CA caused post-resuscitation hyperemia followed by hypoperfusion determined by the level of T-Hb. Hypothermic CA blunted post-resuscitation hyperemia and resulted in more prominent post-resuscitation hypoperfusion. Both, normothermic and hypothermic CA resulted in a sharp decrease in oxygenated Hb and Cyto-C, and the level of oxygenated Hb was higher in hypothermic CA after resuscitation. There was a rapid increase in brain water signals following CA. Hypothermic CA attenuated increased water signals in normothermic CA following resuscitation. CONCLUSION: NIRS can be applied to monitor cerebral blood volume, oxygenation state of Hb, Cyto-C, and water content following CA in rats.

Animals↗
PubMed2004

Complete genome sequence of lymphocystis disease virus isolated from China.

Lymphocystis diseases in fish throughout the world have been extensively described. Here we report the complete genome sequence of lymphocystis disease virus isolated in China (LCDV-C), an LCDV isolated from cultured flounder (Paralichthys olivaceus) with lymphocystis disease in China. The LCDV-C genome is 186,250 bp, with a base composition of 27.25% G+C. Computer-assisted analysis revealed 240 potential open reading frames (ORFs) and 176 nonoverlapping putative viral genes, which encode polypeptides ranging from 40 to 1,193 amino acids. The percent coding density is 67%, and the average length of each ORF is 702 bp. A search of the GenBank database using the 176 individual putative genes revealed 103 homologues to the corresponding ORFs of LCDV-1 and 73 potential genes that were not found in LCDV-1 and other iridoviruses. Among the 73 genes, there are 8 genes that contain conserved domains of cellular genes and 65 novel genes that do not show any significant homology with the sequences in public databases. Although a certain extent of similarity between putative gene products of LCDV-C and corresponding proteins of LCDV-1 was revealed, no colinearity was detected when their ORF arrangements and coding strategies were compared to each other, suggesting that a high degree of genetic rearrangements between them has occurred. And a large number of tandem and overlapping repeated sequences were observed in the LCDV-C genome. The deduced amino acid sequence of the major capsid protein (MCP) presents the highest identity to those of LCDV-1 and other iridoviruses among the LCDV-C gene products. Furthermore, a phylogenetic tree was constructed based on the multiple alignments of nine MCP amino acid sequences. Interestingly, LCDV-C and LCDV-1 were clustered together, but their amino acid identity is much less than that in other clusters. The unexpected levels of divergence between their genomes in size, gene organization, and gene product identity suggest that LCDV-C and LCDV-1 shouldn't belong to a same species and that LCDV-C should be considered a species different from LCDV-1.

Animals↗
PubMed2004

Cerebral cortical aquaporin-4 expression in brain edema following cardiac arrest in rats.

OBJECTIVES: Brain edema occurs following clinical as well as experimental cardiac arrest (CA) and predicts a poor neurologic outcome. The objective of this study was to determine the expression of cerebral cortex aquaporin (AQP)-4, a member of a family of membrane water-channel proteins, in brain edema formation following normothermic or hypothermic CA. METHODS: Twenty-four rats were subjected to time-matched normothermic (N-Sham, 37.5 degrees C +/- 0.5 degrees C, n = 6) or hypothermic (H-Sham, 34 degrees C +/- 0.5 degrees C, n = 6) sham experiments and normothermic (N-CA, n = 6) or hypothermic (H-CA, n = 6) CA induced by asphyxiation for 8 minutes. Hypothermia was induced before CA. The animals were resuscitated with cardiopulmonary resuscitation, ventilation, and epinephrine administration. Brain edema was determined by brain wet-to-dry weight ratio at one hour of resuscitation. AQP4 immunoactivity in the cerebral cortex was determined using immunohistochemical staining and was semiquantified as an intensity of staining with an automated cell imaging system. RESULTS: Mild hypothermia in the sham experiments did not alter cerebral cortex AQP4 immunoactivity (mean +/- SD) (55.0 +/- 3.7 in H-Sham vs. 53.3 +/- 1.7 in N-Sham, p > 0.05). N-CA resulted in a significant increase in AQP4 immunoactivity (61.8 +/- 4.5) compared with N-Sham (p = 0.01) and H-Sham (p = 0.03). H-CA attenuated AQP4 compared with N-CA (53.4 +/- 1.3, p = 0.01). Brain wet-to-dry weight ratios were 4.41 +/- 0.07 in N-Sham, 4.40 +/- 0.08 in H-Sham (p > 0.05 vs. N-Sham), 4.55 +/- 0.04 in N-CA (p = 0.004 vs. N-Sham; p = 0.005 vs. H-Sham), and 4.43 +/- 0.09 in H-CA (p = 0.02 vs. N-CA; p > 0.05 vs. N-Sham and H-Sham). CONCLUSIONS: Cerebral cortical AQP4 expression is up-regulated after normothermic CA, which is attenuated by hypothermia induced before CA.

Animals↗
PubMed2004

[Relationship between the severity, course, fatality of severe acute respiratory syndrome patients and the timing of hospitalization].

OBJECTIVE: To study the relationship of timing of hospitalization and the severity, course, fatality of severe acute respiratory syndrome (SARS) patients. METHOD: 1291 hospital records of clinically diagnosed SARS patients with complete data gathered from "2003 Beijing SARS Clinical Database" were analyzed. RESULTS: SARS cases were categorized into four groups, according to the time of hospitalization after onset of the disease: within 3 days, during day 4 to day 7, during day 8 to day 14 and after day 14. The numbers of cases for each group were 568, 496, 177 and 50 respectively. Data showed that from group 1 to 4, the prevalence rates of major symptoms on the first day of hospitalization were: (1) 9.7%, 16.5%, 23.1% and 24.0% for "feeling chest pain" (P < 0.001), (2) 7.4%, 13.7%, 19.2% and 22.0% for "suffering from breathing obstruction" (P < 0.001), (3) 32.8%, 44.8%, 59.9% and 48.0%, for "coughing" (P < 0.001) and (4) 14.1%, 22.4%, 27.1% and 18.0% for "coughing up phlegm" (P = 0.0002), respectively. The rates of high respiratory frequency (>or= 24 bits/min.) were 11.1%, 15.5%, 22.8% and 25.5% (P < 0.001). The rates of abnormal chest X-ray were 80.3%, 89.0%, 92.3% and 88.9%, respectively (P = 0.002). The average numbers of abnormal lung field (the lung were divided into 6 fields) were 1.7, 1.9, 2.5 and 2.6 (P < 0.001); The numbers of cases receiving continuous oxygen supply treatment were 33.6%, 50.0%, 53.7% and 74.0% (P < 0.001), and the numbers of cases receiving glucocorticosteroids treatment were 28.2%, 35.9%, 53.7% and 62.0% (P < 0.001), respectively. With cases having had chronic baseline diseases prior to SARS infection, the age-standardized fatality rates were 14.9%, 11.7%, 50.0% and 33.9% (P < 0.001), and the average courses of the disease were 30.3, 34.2, 42.9 and 47.5 days (P < 0.001), respectively. In cases without chronic baseline diseases, the age-standardized fatality rates were 5.3%, 9.8%, 9.2% and 8.3% (P = 0.101), and the average courses for each group were 32.4, 35.3, 40.9 and 47.6 days (P < 0.001), respectively. CONCLUSION: Delayed hospitalization would cause the situation of SARS patient to deteriorate, losing the best chance for treatment and increase case fatality. In terms of control program on SARS, emphasize should be paid on decreasing the panic of patients to the disease so as to get early hospitalization.

Adolescent↗
PubMed2004

[Analysis on the cost and its related factors of clinically confirmeds severe acute respiratory syndrome cases in Beijing].

OBJECTIVE: To explore the medical cost and its related factors of clinically confirmed severe acute respiratory syndrome (SARS) cases in Beijing. METHODS: The average medical cost per person/day was calculated on 1272 SARS cases with complete hospitalization data from the Beijing SARS clinical database. Factors associated with medical expenditure were explored by both single factor and multi-factor analyses. RESULTS: The medical costs of SARS patients in Beijing were 18 767.50 RMB/case and 632.02 RMB/day/case. Expenses on medication accounted for the highest proportion (0.66%). The increase in expenses on medication was significantly associated to the increase in total expenditure. Analyses by single factor, factor stratification as well as multi-factor analyses showed that: the expenditure increased significantly with the following factors of the patients: prolonged days of hospitalization, severe symptoms and signs, hospitalization at the early stage of disease onset, being medical staff themselves, with baseline diseases, being applied mechanical ventilation, and with medical insurance. CONCLUSIONS: The medical expenditure on SARS patients at the hospital was higher than that on patients with common diseases which was associated to the following factors as: days of hospitalization, severity of disease, stage of the disease break-out, patient's occupation, baseline disease status, medical insurance status etc.

Age Factors↗
PubMed2004

[The early warning signs of deterioration of severe acute respiratory syndrome].

OBJECTIVE: To explore the risk factors related to severe cases of severe acute respiratory syndrome (SARS) in order to find the early warning signs of deterioration of this disease. METHODS: Three hundred and fifty-five patients with severe SARS and 841 patients with regular SARS from Beijing were studied. RESULTS: Patients with elder age or with comorbid conditions were more likely to develop into severe cases. Data also showed the following characteristics in those severe cases: sustained fever, tachycardia (pulse rate being over 100 per minute), persistent decrease in lymphocytes (< 0.9 x 10(9)/L), increase in neutrophils (> 7.1 x 10(9)/L, 80%), and rapid changes in abnormal chest X-ray. The Cox proportional hazard multi-variable stepwise analysis showed the prediction model of severe SARS included age, comorbid disease, body temperature being still abnormal after 2 days of hospitalization, neutrophil percentage began to increase steadily to more than 80% after 3 days of hospitalization, counts of lymphocytes persisted < 0.9 x 10(9)/L after 4 days of hospitalization. CONCLUSIONS: According to patient's age, comorbid conditions, one can effectively predict the development of the severe SARS by closely monitoring temperature, pulse rate, the counts of lymphocytes and percent of neutrophils.

Adult↗
PubMed2004

[The clinical characteristics and staging of severe acute respiratory syndrome].

OBJECTIVE: To investigate the clinical characteristics and to initiate a clinical staging of severe acute respiratory syndrome (SARS). METHODS: Retrospective analysis was conducted in the clinical symptoms, physical signs and the results of laboratory examinations from 1170 cases with SARS in Beijing, and the clinical characteristics in different stages of the disease were compared. RESULTS: The initial symptom of SARS was pyrexia and the temperature was > 38 degrees C. The natural course of fever was about 14 days. In almost all cases, the respiratory symptoms and systemic toxic manifestations were observed. They came to a climax at the second week and then decreased or nearly disappeared after the third week. The physical signs of SARS were not obvious. The moist rales were observed in 43.3% of patients. Hypoxemia was a common characteristic in SARS. The decrease in partial pressure of oxygen in artery and oxygen saturation in pulse oximeter with normal partial pressure of carbon dioxide was found in most patients at the second week. Abnormal chest X-ray including infiltration and consolidation shadows were seen in 100% of patients. The abnormal images could be found at the first day, enlarged during the second week (to a climax at the 8th or 9th day), and then recovered from the 2 week. The amounts of CD(4)(+), CD(8)(+), and CD(3)(+) of peripheral blood were decreased at the early stage and recovered after 2 or 3 weeks. Some patients suffered from temporary multiple organ dysfunctions (mainly impairments of liver and myocardium). CONCLUSION: The main clinical manifestations of SARS included respiratory and systemic toxic symptoms. The typical course of the disease was about 4 weeks. The first week could be considered as early stage, the second week as fastigium stage, and from the next two weeks as recovery stage.

Blood Gas Analysis↗
PubMed2004

[Side effects of glucocorticosteroids in the management of 1291 patients of SARS].

OBJECTIVE: To analysis the relationship between glucocorticosteroids (GCS) usage and side effects in the treatment of severe acute respiratory syndrome (SARS). METHODS: All clinical records of probable SARS patients in Beijing were collected and input into an Epi6 database, in which 1 291 patients had entire information and met the clinical criteria of SARS. The usage of GCS and GCS associated side effects were analyzed retrospectively. RESULTS: Patients accepted GCS therapy were 83.96% (n=1 084), whereas 16.04%(n=207) did not take GCS. The average dosage of GCS was 160 mg/d in the first week, and then reduced to 80 mg/d and 40 mg/d in the second and the third weeks, respectively. Initial blood glucose, systolic pressure (SBP), and diastolic pressure (DBP) were no significant difference between GCS group and non-GCS group. The highest blood glucose during the treatment in GCS group was markedly higher than that in non-GCS group [(8.68+/-4.80) mmol/L vs (6.39+/-3.71) mmol/L, P<0.05)]. The highest blood glucose and average blood glucose after initiation of GCS therapy were elevated in GCS group. The levels of blood glucose were correlated with the initial, maximum, and cumulative GCS dosages. Average blood glucose was increased markedly in groups with MP(Initial) > or =80 mg/d (Methyprednisonlone), MP(Maximal) > or =160 mg/d, or MP(Cumulative) > or = 3000 mg. The blood glucose grew up significantly in the first and the second weeks in the treatment with GCS, and then returned to normal level gradually. Hyperglycemia duration in the group with MP(Cumulative) > or =3000 mg persisted longer than that in the other groups (P< 0.05). The lowest serum potassium during the treatment and the duration of hypokalemia in GCS group were significantly different from that in non-GCS group [(3.66+/-0.50) mmol/L vs (4.01+/-0.51) mmol/L, P< 0.001 ;1(1, 75) days vs 1(1, 9) days, P<0.05, respectively]. Average serum potassium and the duration of hypokalemia were related to the dosages of GCS. Serum potassium reached its nadir in the first week of GCS treatment and then grew up in the second week. In groups with MP(Initial) > or =320 mg/d, MP(Maximal) > or =320 mg/d, and MP(Cumulative) > or =3000 mg, the level of serum potassium was lower and the duration of hypokalemia was longer than that in other groups. They began to returned to normal level in the third week. Administration of GCS prolonged the time of hypocalcemia[19 (1, 74) days in GCS group vs 8 (1, 32) days in non-GCS group, P< 0.05]. The duration of hypocalcemia was prolonged according to the increasing of the maximal or the cumulative dosage of GCS. However, the duration of hypocalcemia in group with MP(Cumulative) <999 mg was similar to that in non-GCS group (P > 0.05). After GCS administration, SBP and DBP were increased gradually, and reached their peaks in the fourth week [SBP(117.2+/-14.0) mm Hg and DBP (72.5+/-9.1) mm Hg vs SBP (120.0+/-12.5) mm Hg and DBP (74.5+/-8.7) mm Hg, P< 0.05, 1 mm Hg=0.133 kPa]. CONCLUSION: Hyperglycemia and hypokalemia are correlated with GCS dosage and duration. Administration with GCS influences SBP, DBP, and duration of hypocalcemia. Appropriate low dosage of GCS (MP(Initial) and MP(Maximal) < 159 mg/d, MP(Cumulative)< 2999 mg) causes few changes of blood glucose, serum potassium, and blood calcium. It is important to monitor laboratory findings during the treatment with GCS.

Dose-Response Relationship, Drug↗
PubMed2003

[Aprotinin reduces myocardial injury in the off-pump coronary artery bypass grafting].

OBJECTIVE: To investigate the effect of aprotinin on the myocardial injury during the off-pump coronary artery bypass grafting (OPCAB). METHODS: Twenty-four patients undergoing OPCAB randomly were of 12 patients divided into two groups: aprotinin group and Control group (n = 12). In the aprotinin group a loading dose (2 x 10(6) KIU) was administered within the first 30 minutes after the induction followed by continuous infusion of 0.5 x 10(6) KIU/h throughout the operation. The plasma myocardial injury markers CK-MB and cTnI were measured at the four points: (1) After induction; (2) 1 hour after coronary anastomosis; (3) 6 hours and (4) 24 hours after the operation. The blood loss was recorded by autotransfusion in the operation, and the drainage immediately, 6 hours, and 24 hours after the operation. RESULT: Myocardial injury markers CK-MB and cTnI increased significantly after the anastomosis in each group; cTnI was lower in the aprotinin group than in the control group at the third and forth points (P < 0.05). The post-operative drainage after 6 hours and 24 hours were lower in the aprotinin group than in control group (P < 0.05). CONCLUSIONS: There is the myocardial injury during OPCAB. Aprotinin can reduce the myocardial injury during OPCAB.

Aged↗
PubMed2003

[Comparison and correlative analysis of pulmonary function markers after extracorporeal circulation].

OBJECTIVE: To compare the clinic significance of three lung function markers after cardiopulmonary bypass operation. METHODS: Twenty-four patients who continuously took selective coronary artery bypass grafting (CABG) with cardiopulmonary bypass in our hospital were separated randomly to AT group and non AT group according the different treatments of the residue blood in extracorporeal circulation (ECC) circuit, 12 patients in each group. The data of hemodynamics and oxygenation after anesthesia induction and 1, 6, 24, 48 h after ECC were recorded. Respiratory index (RI), oxygenation index (OI) and M index (PaO2/PAO2) were counted and compared at the same time. RESULTS: CI, O2ER, DO2I and VO2I were all elevated obviously after ECC, and Qs/Qt were decreased. There were no difference of all these markers between two groups. RI, OI and PaO2/PAO2 did not change during perioperation in AT group, but in non AT group, RI was increased after ECC, company with the decrease of OI and PaO2/PAO2 at the same time. Nevertheless there was no difference between two groups. But the alterations of the marker percentages were more obviously, there were marked differences between the percentages of RI and PaO2/PAO2 24 h after ECC. All three markers had correlation with Qs/Qt and VO2I. CONCLUSION: RI, OI and PaO2/PAO2 all can reflect appropriately the change of lung function after extracorporeal circulation and the monitor of the developmental alterations individually may be more instructive in clinical practice.

Cardiopulmonary Bypass↗
PubMed2003

Pressure-controlled ventilation attenuates lung microvascular injury in a rat model of activated charcoal aspiration.

BACKGROUND: Previous animal data suggest that aspiration of activated charcoal is associated with pulmonary microvascular injury that may be related to excessive ventilator-induced airway pressures. The purpose of this study was to test the hypothesis that ventilator-induced airway trauma contributes to the lung vascular injury observed following activated charcoal aspiration. METHODS: Capillary filtration coefficient (Kf,c), a sensitive measure of lung microvascular permeability, was determined isogravimetrically prior to and after intratracheal instillation of 0.4 ml/kg (12% weight/vol. solution, pH 7.4) activated charcoal oran equal volume of sterile water in isolated, perfused rat lungs in which ventilation was either pressure-controlled at 10cm H2O or volume-controlled at 5 ml/kg. RESULTS: There was significant lung injury in both activated charcoal groups regardless of ventilation method compared to control lungs or lungs administered sterile water (p < 0.05 ANOVA). However, injury to pressure-controlled ventilated lungs was significantly less than lungs ventilated with traditional, volume-controlled ventilation. CONCLUSION: The results of this investigation demonstrate that pressure-controlled ventilation reduces the lung microvascular injury observed following aspiration of activated charcoal as compared to traditional volume-controlled ventilation methods.

Administration, Inhalation↗
PubMed2002

The effect of lidocaine on early postoperative cognitive dysfunction after coronary artery bypass surgery.

UNLABELLED: We investigated the effect of lidocaine on the incidence of cognitive dysfunction in the early postoperative period after cardiac surgery. One-hundred-eighteen patients undergoing elective coronary artery bypass surgery with cardiopulmonary bypass (CPB) were randomized to receive either lidocaine (1.5 mg/kg bolus followed by a 4 mg/min infusion during operation and 4 mg/kg in the priming solution of CPB) or placebo. A battery of nine neuropsychological tests was administered before and 9 days after surgery. A postoperative deficit in any test was defined as a decline by more than or equal to the preoperative SD of that test in all patients. Any patient showing a deficit in two or more tests was defined as having postoperative cognitive dysfunction. Eighty-eight patients completed pre- and postoperative neuropsychological tests. Plasma lidocaine concentrations (microg/mL) were 4.78 +/- 0.52 (mean +/- SD), 5.38 +/- 0.95, 4.52 +/- 0.39, 5.82 +/- 0.76, and 7.10 +/- 1.09 at 10 min before CPB; 10, 30, and 60 min of CPB; and at the end of operation, respectively. The proportion of patients showing postoperative cognitive dysfunction was significantly reduced in the lidocaine group compared with that in the placebo group (18.6% versus 40.0%; P = 0.028). We conclude that intraoperative administration of lidocaine decreased the occurrence of cognitive dysfunction in the early postoperative period. IMPLICATIONS: Postoperative cognitive dysfunction is a commonly recognized complication after cardiac surgery. Intraoperative cerebral microembolism and hypoperfusion have been proposed to be the major mechanisms. The results of this study show that intraoperative administration of lidocaine decreased the occurrence of early postoperative cognitive dysfunction, perhaps because of its neuroprotective effects.

Aged↗
PubMed2002

Mild hypothermia induced before cardiac arrest reduces brain edema formation in rats.

OBJECTIVES: The mechanisms by which hypothermia improves cardiac arrest (CA)-induced brain damage are unclear. The authors hypothesized that mild hypothermia induced before CA attenuates brain edema formation by preventing neutrophil-mediated dysfunction of the endothelial cell junction proteins. METHODS: Eighteen rats were randomized to normal control surgery (group 1, n = 6), normothermic (37.5 degrees C) CA (group 2, n = 6), or hypothermic (34 degrees C) CA (group 3, n = 6). Hypothermia was induced with external cooling before CA in group 3. Cardiac arrest was induced by 8 minutes of asphyxiation. Brain edema was determined by wet-to-dry weight ratio and cerebral spinal fluid pressure (CSFP). Brain neutrophil content was determined by myeloperoxidase (MPO) activity, and occludin degradation was assessed by western blotting. RESULTS: Normothermic CA significantly increased brain wet-to-dry weight ratio from 4.52 +/- 0.04 in group 1 to 4.80 +/- 0.04 in group 2 (p = 0.0003) and CSFP from 3.6 +/- 0.9 in group 1 to 8.9 +/- 0.9 mm Hg in group 2 (p = 0.004). Mild hypothermia before CA in group 3 significantly reduced brain wet-to-dry weight ratio (4.68 +/- 0.03, p = 0.008 vs. group 2) and CSFP (3.8 +/- 0.5 mm Hg, p = 0.004 vs. group 2). Cardiac arrest increased brain MPO from 0.07 +/- 0.025 in group 1 to 0.16 +/- 0.02 units/gram brain weight in group 2 (p = 0.006) that was not decreased by hypothermia before CA (0.12 +/- 0.02 in group 3 (p = 0.07 vs. group 2). There was no occludin proteolysis in any group. CONCLUSIONS: Mild hypothermia before CA decreases CA-induced brain edema. The hypothermia-elicited reduction in brain edema does not appear to be neutrophil-dependent and the early brain edema formation may not involve the proteolysis of occludin.

Analysis of Variance↗
PubMed2002

Bench to bedside: brain edema and cerebral resuscitation: the present and future.

Sudden cardiac arrest (CA) claims approximately 1,200 lives daily in the United States. Cardiopulmonary resuscitation attempts have so far achieved suboptimal results, and even when restoration of spontaneous circulation (ROSC) is achieved, about 30% of survivors suffer permanent brain damage. This illustrates the need for an improved basic scientific understanding of the pathophysiology of global cerebral injury caused by whole-body ischemia/reperfusion (I/R) injury following CA. Brain edema has been recently documented in experimental CA followed by one hour of ROSC. Brain edema has also been documented in CA and stroke patients by computed tomography or magnetic resonance imaging scanning, and has been shown to predict a poor neurologic outcome. The mechanisms underlying brain edema formation elicited by CA are unclear. New scientific findings of the roles of blood-brain barrier (BBB) permeability, matrix metalloproteinases (MMPs) of a family of proteases, aquaporin 4 (AQP4) of a family of membrane water-channel proteins, and the N-methyl-D-aspartate (NMDA) receptors in the mechanisms underlying CA-elicited brain edema were reviewed. By defining the roles of BBB permeability, MMPs, AQP4, and NMDA receptors in CA-induced brain edema formation, effective new therapeutic strategies to extend cellular and tissue survival, and preserve neurologic function following CA may be feasible.

Animals↗
PubMed2002

[Circulation assist in the radical operation of retro-peritoneal malignancy with the inferior vena cava thrombotic involvement].

OBJECTIVE: To discuss the key role of various mode of circulation assist in the radical operation of retro-peritoneal malignancy with the inferior vena cava thrombotic involvement. METHODS: >From the June 1999 to the March 2001, 6 patients with retro-peritoneal malignancy with thrombosis involving the inferior vena cava, were completely resected with various mode of circulation assist. RESULTS: All the patients operated have good outcomes and follow-up (1 - 20 months) except one death 1 month after operation. CONCLUSION: According to the various types of tumor thrombi, individualized and technically feasible circulation assist mode should be utilized to achieve the satisfactory outcomes.

Aged↗