Search PubMed⌕ Search

Biomedical subjects

Tatu Juvonen

Publications and source records attributed to Tatu Juvonen.

At least 37 records · Page 2Linked to original sources
PubMed2005

pH-stat versus alpha-stat acid-base management strategy during hypothermic circulatory arrest combined with embolic brain injury.

BACKGROUND: There is some evidence of beneficial metabolic effects associated with the pH-stat than with alpha-stat perfusion strategy, but this is tempered by a likely increased risk of embolism to the brain, especially in adult patients. We investigated this possible adverse effect in an experimental model that combined hypothermic circulatory arrest (HCA) and embolic brain injury. METHODS: Twenty-four female juvenile pigs undergoing 25 minutes of HCA at a brain temperature of 18 degrees C were assigned to either alpha-stat (n = 12) or pH-stat (n = 12) strategy during cardiopulmonary bypass. Before the initiation of HCA, the descending aorta was clamped and 200 mg of albumin-coated polystyrene microspheres (250 to 750 microm in diameter) were injected into the isolated aortic arch in both groups. RESULTS: The 7-day survival rate was 75% in the pH-stat group and 50% in the alpha-stat group (p = 0.40). The pH-stat group had significantly better behavioral scores on postoperative days 5 (p = 0.03) and 6 (p = 0.04). The pH-stat strategy was associated with better postoperative intracranial pressures and histopathologic scores, but such differences did not reach statistical significance. The alpha-stat group had lower brain glucose concentrations postoperatively as well as higher brain lactate/glucose and lactate/pyruvate ratios CONCLUSIONS: These results suggest that pH-stat strategy does not cause any worse brain injury than the alpha-stat strategy. Indeed, the pH-stat strategy is associated with a slightly better outcome compared with the alpha-stat strategy, even in the setting of cerebral embolization. This observation suggests that the pH-stat strategy could also be used in adults during deep hypothermic cardiopulmonary bypass despite the increased risk of intraoperative cerebral embolization.

Animals↗
PubMed2005

Predictors of postoperative mortality after mitral valve repair: analysis of a series of 164 patients.

BACKGROUND: Mitral valve repair (MVR) has been shown to achieve good long-term results. However, this procedure is associated with relevant immediate postoperative mortality. The aim of this study is to identify those preoperative variables associated with an increased risk of 30-d postoperative death. METHODS: One hundred and sixty-four patients underwent MVR at our institution from January 1993 to December 2000. RESULTS: Eleven patients (6.7%) died during the immediate postoperative outcome, a median of 14 d after surgery (range, 1-29 d). One patient (1.3%) out of 80 who underwent MVR as lone procedure died on postoperative day 14 of cardiac tamponade. The mortality rate in those who underwent MVR associated with other procedures was 11.9%. Multivariable analysis (154 patients included in the analysis) showed that patients' age (p = 0.006, for an increase of 10 units: OR 4.33, 95% CI 1.53-12.27), history of prior cardiac surgery (p = 0.006, OR 118.56, 95% CI 4.03-3491.14) and NYHA functional class (p = 0.011, OR 5.66, 95% CI 1.49-21.49) were significantly associated with an increased risk of postoperative death. The receiver operating characteristics (ROC) curve showed that patients' age had an area under the curve of 0.762 (95% CI 0.622-0.901, p = 0.004), its best cut-off value being 65 years (mortality, 13.4% vs 2.1%, p = 0.008, sensitivity 81.8%, specificity 62.1%, accuracy 63.4%). None of the patients older than 65 and with a history of prior cardiac surgery survived the operation. CONCLUSIONS: MVR is associated with a relevant 30-d mortality risk in patients older than 65 years, with advanced NYHA functional class and a history of prior cardiac surgery.

Age Distribution↗
PubMed2005

Outcome after emergency repair of symptomatic, unruptured abdominal aortic aneurysm: results in 42 patients and review of the literature.

OBJECTIVE: To evaluate the results of our experience in the management of patients with symptomatic, unruptured abdominal aortic aneurysm (AAA), to identify the predictors of immediate outcome and to define the worldwide postoperative mortality rate through a review of previous studies on this condition. PATIENTS AND METHODS: Forty-two patients underwent emergency repair for symptomatic, unruptured AAA. RESULTS: Four patients (9.5%) died during the in-hospital stay, three of myocardial infarction and one of multiorgan failure. Only preoperative creatinine was predictive of postoperative death (p = 0.04, OR 1.31). The Glasgow Aneurysm Score tended to be predictive of postoperative death (p = 0.06), survivors having had a median score of 76.0 (IQR, 75.5-82.1) and patients who died of 87.1 (78.9-89.9). The receiver operating characteristic (ROC) curve analysis showed that the Glasgow Aneurysm Score had an area under the curve of 0.789 (95% CI: 0.596-0.983, SE: 0.099, p = 0.06). Its best cut-off value in predicting postoperative death was 85 (specificity 86.8%, sensitivity 75.0%). The postoperative mortality rate among patients with a Glasgow Aneurysm Score <85 was 2.9%, whereas it was 37.5% among those with a score >85 (p = 0.003). A review of the results of previous studies on this condition, including also the present series, showed that 207 out of 1312 patients (15.8%) died after emergency operation for symptomatic, unruptured AAA. CONCLUSION: Emergency open repair of symptomatic, unruptured AAA is associated with a high risk of postoperative death. The results of this study suggest that a rather good postoperative survival rate can be expected in patients with a Glasgow Aneurysm Score <85. A watchful waiting policy or, alternatively, emergency endovascular repair should be advocated in patients with a higher score.

Aged↗
PubMed2005

Long-term outcome after mitral valve repair.

BACKGROUND: Several studies reported excellent long-term results after mitral valve repair for regurgitation, however a number of patients still experience recurrent mitral valve regurgitation which requires reoperation. We have evaluated the long-term outcome of a consecutive series of patients who underwent mitral valve repair for regurgitation in an attempt to identify the risk factors associated with late failures. PATIENTS AND METHODS: One-hundred and sixty-four patients underwent mitral valve repair for ischemic and degenerative mitral valve regurgitation. Seventy-two patients underwent echocardiographic evaluation a median of 5.6 years after surgery. RESULTS: Ten-year survival freedom from any fatal cardiac event was 75.9% and survival freedom from redo mitral valve surgery was 93.8%. Multivariable analysis showed that residual mitral valve regurgitation grade>1 as assessed during the immediate postoperative period (at 10-year, 60.6% vs. 95.7%, p=0.001, RR 20.7, 95%C.I. 3.4-125.3) and chronic obstructive pulmonary disease/asthma (at 10-year 66.8% vs. 95.2%, p=0.013, RR 12.0, 95%C.I. 1.7-85.2) were predictors of redo mitral valve surgery. The same findings were observed also among patients with myxomatous degenerative disease. At echocardiographic follow-up, no significant improvement was detected in terms of left ventricular ejection fraction, whilst mitral valve regurgitation grade (median, 3 to 1), New York Heart Association class (median, 2 to 1) and left atrium diameter (median, 50 to 44 mm) decreased significantly. CONCLUSIONS: This study confirms the excellent clinical long-term results after mitral valve repair. An adequate repair technique is advocated in order to decrease the immediate postoperative rate of residual regurgitation>1 as this is a main determinant of late failures requiring redo mitral valve surgery. Further studies are required to better define the possible causative role of chronic obstructive pulmonary disease and any underlying connective tissue metabolic disorder in late failures after mitral valve repair.

Aged↗
PubMed2005

Leukocyte depleting filter attenuates myocardial injury during elective coronary artery bypass surgery.

BACKGROUND: Ischemia-reperfusion injury secondary to leukocyte activation has been widely recognized as one of the most relevant mechanism leading to postoperative organ dysfunction occurring after a period of ischemia. The aim of the present study was to evaluate in a prospective, randomized study, the value of leukocyte depleting filter in patients undergoing elective coronary artery bypass surgery. METHODS: Twenty patients scheduled for elective on-pump coronary artery bypass surgery were randomized to undergo cardiopulmonary bypass either with a leukocyte depleting filter incorporated in the extracorporeal circulation arterial line or without a filter. RESULTS: The main finding of this study was the significantly lower postoperative concentrations of cardiac troponin I in the leukocyte filter group (Tests of between-subjects effects: p = 0.024). There were also slightly better cardiac indices in the leukocyte filter group. A larger amount of blood units was infused intra- and postoperatively in patients undergoing cardiopulmonary bypass with leukocyte filtration (median, 600 [IQR, 0-1200] vs. 0 [IQR, 0-600], p = 0.08). Two patients in the leukocyte filter group underwent reoperation for bleeding but none in the control group (p = 0.48). Intra-and postoperative platelet count was lower in the leukocyte filter group (Tests of between-subjects effects: p = 0.08). Despite a significant increased concentration of C-reactive protein on the first postoperative day in the control group (p = 0.029), repeated-measures analysis failed to show any significant increase during the study period (p = 0.33). CONCLUSIONS: The results of this study suggest a myocardial protective effect of leukocyte filter in the setting of elective coronary artery bypass surgery.

Aged↗
PubMed2005

Quality of life after mitral valve repair.

BACKGROUND AND AIM OF THE STUDY: Mitral valve repair for degenerative and ischemic mitral valve regurgitation has been shown to be a durable procedure. The study aim was to evaluate the quality of life of patients who had undergone mitral valve repair, and to compare it to that of an age- and gender-adjusted Finnish general population. METHODS: Among 130 late survivors after mitral valve repair, 109 (83.8%) answered the RAND-36 Health Survey questionnaire; these patients form the basis of the present study. RESULTS: The Wilcoxon test showed significantly higher mental health (p = 0.04) and pain scores (p = 0.015) and a lower role functioning/physical score (p = 0.008) in the study group. The scores of the other RAND-36 Health Survey variables of the study group were similar to those of the age- and gender-adjusted general population. The mean total score for the study group was 512 (median 532, IQR 360-678), compared to 522 (median 538, IQR 468-549) in the general population (p = 0.72) (only 95 patients were included in the analysis due to isolated missing scores). CONCLUSION: The quality of life of long-term survivors after mitral valve repair, as assessed by the RAND-36 Health Survey, is similar to that of an age- and gender-adjusted general Finnish population.

Aged↗
PubMed2004

Predictors of development of anastomotic femoral pseudoaneurysms after aortobifemoral reconstruction for abdominal aortic aneurysm.

BACKGROUND: The pathogenesis of anastomotic femoral pseudoaneurysms (AFPs) is still unclear. We have performed this long-term retrospective study of patients who underwent aortobifemoral reconstruction for abdominal aortic aneurysm (AAA) in order to better establish the long-term rate of AFP and to identify the predictors of its late occurrence. METHODS: The long-term outcome of 178 patients who underwent and survived aortobifemoral reconstruction for infrarenal AAA was reviewed. RESULTS: During a median follow-up of 5.2 years, 28 AFPs developed in 19 patients. Six AFPs were recurrent. The mean linearized rate of AFPs was 1.88% per year. At 15 years, the survival-freedom rate from AFPs was 60%, and from repair of AFPs it was 62%. The survival-freedom rate from AFP was significantly poorer in patients with chronic obstructive pulmonary disease (P = 0.017; at 10 years: 64.3% versus 92.3%), hyperlipidemia (P = 0.0056; at 10 years: 59.2% versus 87.5%), current smoking (P <0.0001; at 10 years: 65.8% versus 94.5%), and postoperative inguinal wound infection (P <0.0001; at 10 years: 42.8% versus 86.8%). Multivariate analysis showed that chronic obstructive pulmonary disease (relative risk [RR]: 3.05, 95% confidence interval [CI]: 1.04 to 8.95), current smoking (RR: 5.38, 95% CI: 1.62 to 17.90), and postoperative inguinal wound infection (RR: 9.04, 95% CI: 2.76 to 29.96) were significantly associated with the development of AFPs. The linearized rate of AFPs was significantly higher only among current smokers (P <0.0001, 4.4% versus 0.8% per year) and among those who had inguinal wound infection (P = 0.001, 9.2% versus 1.5% per year). CONCLUSIONS: Current smoking and inguinal wound infection may contribute to the development of AFP after aortobifemoral reconstruction for AAA, likely by affecting reparative connective tissue mechanisms at the anastomotic site.

Anastomosis, Surgical↗
PubMed2004

Postoperative atrial fibrillation is a major cause of stroke after on-pump coronary artery bypass surgery.

BACKGROUND: Atrial fibrillation, occurring after coronary artery bypass grafting (CABG), has been suggested to be associated with the development of postoperative stroke. However, it is not clear what is the incidence of atrial fibrillation-related postoperative stroke, the timing of its occurrence, and the outcome. These issues have been investigated in a consecutive series of patients who have undergone on-pump coronary artery bypass grafting (ONCAB). METHODS: Among 2,630 patients who underwent ONCAB, 52 patients (2.0%) experienced postoperative stroke and form the basis of the present study. RESULTS: Twelve patients (23.1%) died postoperatively. The ischemic cerebral event occurred after a mean of 3.7 days (range, 0 to 33). In 19 patients (36.5%), atrial fibrillation preceded the occurrence of neurologic complication. These patients experienced a mean of 2.5 episodes of atrial fibrillation before the occurrence of neurologic complication. The cerebrovascular event occurred after a mean of 6.0 days in patients in whom atrial fibrillation preceded it, after a mean of 1.2 days in those with calcified ascending aorta, and after a mean of 3.1 days in those without calcified ascending aorta or in whom atrial fibrillation did not precede the cerebrovascular complication (p < 0.0001). Stroke occurred a mean of 21.3 hours after atrial fibrillation. CONCLUSIONS: This study confirmed that atrial fibrillation, occurring after CABG, is a major determinant of postoperative stroke. Prevention of postoperative atrial fibrillation, and of formation of clots into the left atrium, may dramatically reduce the risk of postoperative stroke.

Aortic Diseases↗
PubMed2004

Pulmonary artery blood temperature at admission to the intensive care unit is predictive of outcome after on-pump coronary artery bypass surgery.

OBJECTIVE: To evaluate whether pulmonary artery blood (PA) temperature on admission to the intensive care unit (ICU) is predictive of postoperative outcome after isolated on-pump coronary artery bypass grafting (CABG). DESIGN: A retrospective study on 1639 patients who underwent isolated on-pump CABG in whom PA temperature at admission to the ICU was available for review. RESULTS: Thirty-three patients (2.0%) died during the in-hospital stay and 87 patients (5.3%) developed low cardiac output syndrome. PA temperature at admission to the ICU was significantly associated with an increased risk of overall postoperative death (p = 0.002), cardiac death (p = 0.03), and low cardiac output syndrome (p < 0.0001), and was significantly correlated with prolonged length of ICU stay (p < 0.0001) and postoperative bleeding (p = 0.001). Patients with high PA temperature had significantly more severe comorbidities, and longer aortic cross-clamping and cardiopulmonary bypass time. The receiver operating characteristic curve showed that PA temperature at admission to the ICU in predicting postoperative death had an area under the curve of 0.660 (p = 0.002) and its best cut-off value was 36.4 degrees C (sensitivity: 63.6%, specificity: 65.2%). When the PA temperature at admission to the ICU was > or = 36.4 degrees C, the postoperative mortality and low cardiac output syndrome rates were 3.6 and 8.3%, whereas they were 1.1 and 3.7% when the PA temperature at admission to the ICU was < 36.4 degrees C (p = 0.001, p < 0.0001), respectively. CONCLUSION: Patients having a PA temperature > or =36.4 degrees C at admission to the ICU after CABG seem to be at higher risk of poor postoperative outcome.

Aged↗
PubMed2004

Apotransferrin, C1-esterase inhibitor, and alpha 1-acid glycoprotein for cerebral protection during experimental hypothermic circulatory arrest.

BACKGROUND: Because of current limitations in improving metabolic support to the brain during hypothermic circulatory arrest (HCA), attenuation of ischemia-reperfusion injury remains an area of therapeutic intervention of relevance. Apotransferrin (Apo-Tf), alpha 1-acid glycoprotein (AGP), and C1-esterase inhibitor (C1-INH) have been herein evaluated as potential beneficial agents in reducing the ischemia-reperfusion injury in a surviving model of HCA. METHODS: Apo-Tf 100 mg/kg (n = 6), C1-INH 50 IU/kg (n = 6), AGP 100 mg/kg (n = 6), or NaCl 0.9% 2 ml/kg (n = 6) were randomly administered to 24 juvenile pigs after a 75-min period HCA at a brain temperature of 18 degrees C. RESULTS: Animals in the Apo-Tf group had a slightly better 7-day survival (66.7%) compared with the other study groups (50%), but such a difference was not statistically significant. Some favorable changes in the brain glucose metabolism parameters were observed in the AGP, C1-INH, and Apo-Tf groups, but these did not reach statistical significance. Semiquantitative analysis of the histopathological findings did not show any significant difference between the study groups. However, only two out of four surviving animals in the Apo-Tf group developed brain infarction, whereas all three survivors of the remaining study groups developed brain infarction. CONCLUSIONS: Although the small size of the study groups may affect the present findings, none of the metabolic and hemodynamic parameters as well as outcome endpoints indicate a substantial therapeutic efficacy of Apo-Tf, AGP, and C1-INH as neuroprotective agents after experimental HCA.

Animal Experimentation↗
PubMed2003

Aneurysm of the profunda femoris artery manifested as acute groin pain in a child.

Arterial aneurysms in children are extremely rare and can be of congenital, inflammatory, and infectious nature or secondary to trauma. The authors describe the case of a 8-year-old boy who was admitted in the hospital with fever and severe groin pain. He had a true saccular aneurysm of 4 cm in diameter originating from the profunda femoris artery with, according to the clinical and angiographic findings, arteriovenous communication with the femoral veins. Because the aneurysm was firmly adherent to the deep femoral vein, the latter was resected and the venous continuity was restored with a saphenous vein bypass graft. The patient recovered without any complication. The histologic examination showed a normal intimal layer and partially disrupted medial elastic fibers without inflammatory infiltrate, suggesting the diagnosis of a true arterial aneurysm.

Arteriovenous Fistula↗
PubMed2003

pH-stat versus alpha-stat perfusion strategy during experimental hypothermic circulatory arrest: a microdialysis study.

BACKGROUND: The superiority of the pH-stat to the alpha-stat acid-base strategy during cardiopulmonary bypass as a neuroprotective method during hypothermic circulatory arrest is still controversial. In the present study, brain metabolism and outcome have been evaluated in a surviving model of experimental hypothermic circulatory arrest. METHODS: Twenty pigs undergoing 75-minutes of hypothermic circulatory arrest at a brain temperature of 18 degrees C were randomly assigned to the alpha-stat (n = 10) or pH-stat (n = 10) strategy during cardiopulmonary bypass. RESULTS: The 7-day survival rate was 90% (9 of 10) in the pH-stat group and 10% (1 of 10) in the alpha-stat group. At the end of cooling, pH-stat strategy was associated with significantly lower brain lactate and pyruvate concentrations and brain lactate-glucose ratio. After reperfusion, brain concentrations of glycerol, lactate, pyruvate, and lactate-glucose ratio were significantly lower in the pH-stat group. This strategy was associated with a faster rise of brain tissue temperature and reoxygenation on reperfusion, which is likely secondary to improved cerebral perfusion. CONCLUSIONS: During cardiopulmonary bypass before and after a period of hypothermic circulatory arrest, acid-base management according to the pH-stat principles seemed to be associated with less derangements in cerebral metabolism, lower intracranial pressures, and excellent behavioral recovery and survival outcome. Because there is strong evidence of the beneficial metabolic effects related to this method, further studies using an experimental model of combined HCA and embolic brain injury are required to exclude a possible increased risk of cerebral embolism associated with the pH-stat strategy.

Animals↗
PubMed2003

Candidate locus analysis of familial ascending aortic aneurysms and dissections confirms the linkage to the chromosome 5q13-14 in Finnish families.

OBJECTIVE: The purpose of the study was to carry out a candidate gene analysis in families with familial thoracic aortic aneurysms and dissections. METHODS: The study material consisted of 11 Finnish families (with 115 members genotyped) who underwent echocardiographic examination for measurement of the aortic root diameter. Selected candidate genes included the loci for Marfan and Ehlers-Danlos syndromes, the genes of matrix metalloproteinases 3 and 9 and tissue inhibitor of metalloproteinase 2 as well two loci on the chromosomes 5q13-14 and 11q23.2-q24, previously found to be linked to the disease. RESULTS: The chromosomal locus 5q13-14 was linked to the disease risk (nonparametric linkage score 3.0, P =.005) confirming the previous linkage. Other candidate genes and loci were excluded as major loci in these families. CONCLUSIONS: The identification of the gene at chromosomal location 5q13-14 causing the development of such diseases would give us important knowledge on the pathogenesis of the disease and enable the identification of subjects at risk. This in turn would lead to appropriate treatment before the occurrence of fatal complications and, likely, to the development of new treatment methods.

Adult↗
PubMed2003

Fructose-1,6-bisphosphate for improved outcome after hypothermic circulatory arrest in pigs.

OBJECTIVE: Fructose-1,6-bisphosphate is a high-energy intermediate in the anaerobic metabolism. It enhances glycolysis, preserves cellular adenosine triphosphate, and prevents the increase of intracellular calcium during ischemia. The potential neuroprotective effect of fructose-1,6-bisphosphate during hypothermic circulatory arrest was evaluated in a surviving porcine model. METHODS: Twenty-four pigs were randomly assigned to receive two intravenous infusions of either fructose-1,6-bisphosphate (500 mg/kg) or saline solution. The first infusion was given immediately before a 75-minute period of hypothermic circulatory arrest and the second was given immediately after hypothermic circulatory arrest. RESULTS: The 7-day survivals were 83.3% in the fructose-1,6-bisphosphate group and 41.7% in the control group (P =.09). The treated animals had significantly better postoperative behavioral scores. The administration of fructose-1,6-bisphosphate was associated with higher venous phosphate and sodium levels, lower venous ionized calcium levels, higher blood osmolarity, and a better fluid balance. Intracranial pressure and venous creatine kinase isoenzyme MB were significantly lower in the fructose-1,6-bisphosphate group during rewarming (P =.01 and P =.001, respectively). Among the treated animals, brain glucose, pyruvate and lactate levels tended to be higher, brain glycerol levels tended to be lower, and the histopathologic score of the brain was significantly lower (P =.04). CONCLUSIONS: Intravenous administration of fructose-1,6-bisphosphate at 500 mg/kg before and after hypothermic circulatory arrest in a surviving porcine model was associated with better survival, behavioral outcome, and histopathologic score. The observed lower blood creatine kinase isoenzyme MB and brain glycerol levels and the higher brain glucose, pyruvate, and lactate levels in the fructose-1,6-bisphosphate group suggest that this drug has supportive effects on myocardial and brain metabolisms.

Animals↗
PubMed2003

Familial abdominal aortic aneurysms: collection of 233 multiplex families.

OBJECTIVE: This study investigated a large number of families in which at least two individuals were diagnosed with abdominal aortic aneurysms to identify the relationship of the affected relatives to the proband. SUBJECTS AND METHODS: Families for the study were recruited through various vascular surgery centers in the United States, Finland, Belgium, Canada, the Netherlands, Sweden, and the United Kingdom and through our patient recruitment website (www.genetics.wayne.edu/ags). RESULTS: We identified 233 families with at least two individuals diagnosed with abdominal aortic aneurysms. The families originated from nine different nationalities, but all were white. There were 653 aneurysm patients in these families, with an average of 2.8 cases per family. Most of the families were small, with only two affected individuals. There were, however, six families with six, three with seven, and one with eight affected individuals. Most of the probands (82%) and the affected relatives (77%) were male, and the most common relationship to the proband was brother. Most of the families (72%) appeared to show autosomal recessive inheritance pattern, whereas in 58 families (25%), abdominal aortic aneurysms were inherited in autosomal dominant manner, and in eight families, the familial aggregation could be explained by autosomal dominant inheritance with incomplete penetrance. In the 66 families where abdominal aortic aneurysms were inherited in a dominant manner, 141 transmissions of the disease from one generation to another were identified, and the male-to-male, male-to-female, female-to-male, and female-to-female transmissions occurred in 46%, 11%, 32%, and 11%, respectively. CONCLUSION: Our study supports previous studies about familial aggregation of abdominal aortic aneurysms and suggests that first-degree family members, male relatives, in particular, are at increased risk. No single inheritance mode could explain the occurrence of abdominal aortic aneurysms in the 233 families studied here, suggesting that abdominal aortic aneursyms are a multifactorial disorder with multiple genetic and environmental risk factors.

Aortic Aneurysm, Abdominal↗
PubMed2003

EEG burst recovery is predictive of brain injury after experimental hypothermic circulatory arrest.

OBJECTIVE: To evaluate whether electroencephalography (EEG) recovery could be considered a reliable marker of brain injury after experimental hypothermic circulatory arrest (HCA). DESIGN: Cortical electrical activity was registered before and after a 75-min period of HCA in 27 pigs that survived 7 days after the experiment. The sum of EEG bursts was counted as a percentage of the sum of artifact-free bursts and suppressions, and this percentage was used as a measure of EEG activity in the analysis. RESULTS: Brain infarction developed in 13 animals (48.1%), in 12 cases (44.4%) having involved the cortex, in 1 case the thalamus (3.7%) and in another the hippocampus (3.7%). The mean EEG burst percentage significantly correlated with the total brain histopathological score (rho = -0.588, P = 0.001). EEG burst percentage from the 2 h 20 min to the 7 h 20 min interval correlated with the total brain histopathological score and with the cortex, brainstem and cerebellum scores. The mean EEG burst percentage rate was higher, but not significantly, among the animals without brain infarction (38.5% vs 32.4%), but such a difference was significant at the 3 h 20 min postoperative interval (P = 0.02). The mean EEG burst percentage significantly correlated with brain glucose concentration at the 1 h interval (rho = 0.387; P = 0.046), brain lactate concentration at the 2 h interval (rho = -0.431; P = 0.025), and the brain lactate/glucose ratio at the 1 h 30 min interval from the start of rewarming (rho = -0.433; P = 0.024). CONCLUSION: A decreased EEG burst percentage seems to be associated with an increased risk of developing histologically evident brain ischemic injury in the cortex, brainstem and cerebellum after experimental HCA.

Animals↗