[Effects of cerebral oxygen changes during coronary bypass surgery on postoperative cognitive dysfunction in elderly patients: a pilot study]. / Efeitos das alterações no oxigênio cerebral durante cirurgia de revascularização do miocárdio sobre a disfunção cognitiva no pós­operatório em pacientes idosos: estudo piloto.

BACKGROUND AND OBJECTIVES: Postoperative cognitive dysfunction is common after cardiac surgery. Adequate cerebral perfusion is essential and near infrared spectroscopy (NIRS) can measure cerebral oxygenation. Aim of this study is to compare incidence of early and late postoperative cognitive dysfunction in elderly patients treated with conventional or near infrared spectroscopy monitoring. METHODS: Patients undergoing coronary surgery above 60 years, were included and randomized to 2 groups; control and NIRS groups. Peroperative management was NIRS guided in GN; and with conventional approach in control group. Test battery was performed before surgery, at first week and 3 rd month postoperatively. The battery comprised clock drawing, memory, word list generation, digit spam and visuospatial skills subtests. Postoperative cognitive dysfunction was defined as drop of 1 SD (standard deviation) from baseline on two or more tests. Mann-Whitney U test was used for comparison of quantitative measurements; Chi-square exact test to compare quantitative data. RESULTS: Twenty-one patients in control group and 19 in NIRS group completed study. Demographic and operative data were similar. At first week postoperative cognitive dysfunction were present in 9 (45%) and 7 (41%) of patients in control group and NIRS group respectively. At third month 10 patients (50%) were assessed as postoperative cognitive dysfunction; incidence was 4 (24%) in NIRS group (p:0.055). Early and late postoperative cognitive dysfunction group had significantly longer ICU stay (1.74+0.56 vs. 2.94+0.95; p<0.001; 1.91+0.7 vs. 2.79+1.05; p<0.01) and longer hospital stay (9.19+2.8 vs. 11.88+1.7; p<0.01; 9.48+2.6 vs. 11.36+2.4; p<0.05). CONCLUSION: In this pilot study conventional monitoring and near infrared spectroscopy resulted in similar rates of early postoperative cognitive dysfunction. Late cognitive dysfunction tended to ameliorate with near infrared spectroscopy. Early and late cognitive declines were associated with prolonged ICU and hospital stays.

The effect of two different glycemic management protocols on postoperative cognitive dysfunction in coronary artery bypass surgery / Efeito de dois protocolos de controle glicêmico diferentes sobre a disfunção cognitiva após cirurgia de revascularização do miocárdio

Abstract Introduction: Postoperative cognitive dysfunction (POCD) is an adverse outcome of surgery that is more common after open heart procedures. The aim of this study is to investigate the role of tightly controlled blood glucose levels during coronary artery surgery on early and late cognitive decline. Methods: 40 patients older than 50 years undergoing elective coronary surgery were randomized into two groups. In the "Tight Control" group (GI), the glycemia was maintained between 80 and 120 mg dL-1 while in the "Liberal" group (GII), it ranged between 80-180 mg dL-1. A neuropsychological test battery was performed three times: baseline before surgery and follow-up first and 12th weeks, postoperatively. POCD was defined as a drop of one standard deviation from baseline on two or more tests. Results: At the postoperative first week, neurocognitive tests showed that 10 patients in the GI and 11 patients in GII had POCD. The incidence of early POCD was similar between groups. However the late assessment revealed that cognitive dysfunction persisted in five patients in the GII whereas none was rated as cognitively impaired in GI (p = 0.047). Conclusion: We suggest that tight perioperative glycemic control in coronary surgery may play a role in preventing persistent cognitive impairment.

Resumo Introdução: A disfunção cognitiva pós-operatória (DCPO) é um resultado adverso cirúrgico que é mais comum após cirurgias cardíacas abertas. O objetivo deste estudo foi investigar o papel dos níveis de glicose no sangue rigorosamente controlados durante a cirurgia coronariana no declínio cognitivo precoce e tardio. Métodos: Foram randomizados em dois grupos 40 pacientes acima de 50 anos e submetidos à cirurgia coronariana eletiva. No grupo "controle rigoroso" (GI), a glicemia foi mantida entre 80-120 mg.dL-1; enquanto no grupo "liberal" (GII), variou entre 80-180 mg.dL-1. A bateria de testes neuropsicológicos foi feita três vezes: fase basal, antes da cirurgia e na primeira e 12ª semana de acompanhamento no pós-operatório. DCPO foi definida como uma queda de um desvio padrão da fase basal em dois ou mais testes. Resultados: Na primeira semana de pós-operatório, os testes neurocognitivos mostraram que 10 pacientes no GI e 11 pacientes no GII apresentaram DCPO. A incidência de DCPO precoce foi semelhante entre os grupos. No entanto, a avaliação tardia revelou que a disfunção cognitiva persistiu em cinco pacientes no GII, enquanto nenhum paciente foi classificado como cognitivamente prejudicado no GI (p = 0,047). Conclusão: Sugerimos que o controle glicêmico rigoroso no perioperatório de cirurgia coronariana pode desempenhar um papel na prevenção da deterioração cognitiva persistente.

[The effect of two different glycemic management protocols on postoperative cognitive dysfunction in coronary artery bypass surgery]. / Efeito de dois protocolos de controle glicêmico diferentes sobre a disfunção cognitiva após cirurgia de revascularização do miocárdio.

INTRODUCTION: Postoperative cognitive dysfunction (POCD) is an adverse outcome of surgery that is more common after open heart procedures. The aim of this study is to investigate the role of tightly controlled blood glucose levels during coronary artery surgery on early and late cognitive decline. METHODS: 40 patients older than 50 years undergoing elective coronary surgery were randomized into two groups. In the "Tight Control" group (GI), the glycemia was maintained between 80 and 120mg·dL-1 while in the "Liberal" group (GII), it ranged between 80-180mg·dL-1. A neuropsychological test battery was performed three times: baseline before surgery and follow-up first and 12th weeks, postoperatively. POCD was defined as a drop of one standard deviation from baseline on two or more tests. RESULTS: At the postoperative first week, neurocognitive tests showed that 10 patients in the GI and 11 patients in GII had POCD. The incidence of early POCD was similar between groups. However the late assessment revealed that cognitive dysfunction persisted in five patients in the GII whereas none was rated as cognitively impaired in GI (p=0.047). CONCLUSION: We suggest that tight perioperative glycemic control in coronary surgery may play a role in preventing persistent cognitive impairment.

Patient state index and cerebral blood flow changes during shoulder arthroscopy in beach chair position / Patient State Index e alterações do fluxo sanguíneo cerebral durante artroscopia do ombro em posição de cadeira de praia

Abstract Background and objectives: The aim of the study were to demonstrate the possible hemodynamic changes and cerebral blood flow alterations in patients who were positioned from supine to beach chair position; and to detect if the position change causes any cortical activity alteration as measured by the 4-channeled electroencephalography monitor. Methods: 35 patients were included. Before the induction, mean arterial pressure and patient state index values were recorded (T0). After the intubation, doppler-ultrasonography of the patients’ internal carotid and vertebral arteries were evaluated to acquire cerebral blood flow values from the formula. In supine position, mean arterial pressure, patient state index and cerebral blood flow values were recorded (T1) and the patient was positioned to beach chair position. After 5 min all measurements were repeated (T2). Measurements of patient state index and mean arterial pressure were repeated after 20 (T3), and 40 (T4) min. Results: There was a significant decrease between T0 and T1 in heart rate (80.5 ± 11.6 vs. 75.9 ± 14.4 beats/min), MAP (105.8 ± 21.9 vs. 78.9 ± 18.4 mmHg) and PSI (88.5 ± 8.3 vs. 30.3 ± 9.7) (all p < 0.05). Mean arterial pressure decreased significantly after position change, and remained decreased, compared to T1. The overall analysis of patient state index values (T1-T4) showed no significant change; however, comparing only T1 and T2 resulted in a statically significant decrease in patient state index. There was a significant decrease in cerebral blood flow after beach chair position. Conclusion: Beach chair position was associated with a decrease in cerebral blood flow and patient state index values. Patient state index was affected by the gravitational change of the cerebral blood flow; however, both factors were not directly correlated to each other. Moreover, the decrease in patient state index value was transient and returned to normal values within 20 min.

Resumo Justificativa e objetivos: Demonstrar as possíveis alterações hemodinâmicas e do fluxo sanguíneo cerebral (FSC) em pacientes que foram posicionados de supinação para cadeira de praia (CP) e detectar se a mudança de posição causa alguma alteração na atividade cortical como mensurado pelo monitor de EEG com quatro canais. Métodos: Foram incluídos 35 pacientes. Antes da indução, os valores da PAM e do IEP foram registrados (T0). Após a intubação, ultrassonografias com Doppler da carótida interna e artérias vertebrais dos pacientes foram avaliadas para adquirir os valores do FSC a partir da fórmula. Em supinação, os valores da PAM, IEP e FSC foram registrados (T1) e o paciente foi posicionado em CP. Após cinco minutos, todas as mensurações foram repetidas (T2). As mensurações do IEP e PAM foram repetidas após 20 (T3) e 40 minutos (T4). Resultados: Houve uma diminuição significativa entre T0 e T1 na FC (80,5 ± 11,6 vs. 75,9 ± 14,4 bpm), PAM (105,8 ± 21,9 vs. 78,9 ± 18,4 mmHg) e IEP (88,5 ± 8,3 vs. 30,3 ± 9,7) (p < 0,05 para todos). A PAM diminuiu significativamente após a mudança de posição e permaneceu diminuída em relação a T1. A análise global dos valores do IEP (T1-T4) não mostrou mudança significativa, mas a comparação de apenas T1 e T2 resultou em redução estatisticamente significativa do IEP. Houve redução significativa do FSC após o posicionado em CP. Conclusão: O posicionado em CP foi associado à diminuição do FSC e dos valores do IEP. O IEP foi afetado pela mudança gravitacional do FSC; no entanto, ambos os fatores não estavam diretamente correlacionados. Além disso, a diminuição do valor do IEP foi transitória e voltou aos valores normais dentro de 20 minutos.

Patient state index and cerebral blood flow changes during shoulder arthroscopy in beach chair position.

BACKGROUND AND OBJECTIVES: The aim of the study were to demonstrate the possible hemodynamic changes and cerebral blood flow alterations in patients who were positioned from supine to beach chair position; and to detect if the position change causes any cortical activity alteration as measured by the 4-channeled electroencephalography monitor. METHODS: 35 patients were included. Before the induction, mean arterial pressure and patient state index values were recorded (T0). After the intubation, doppler-ultrasonography of the patients' internal carotid and vertebral arteries were evaluated to acquire cerebral blood flow values from the formula. In supine position, mean arterial pressure, patient state index and cerebral blood flow values were recorded (T1) and the patient was positioned to beach chair position. After 5min all measurements were repeated (T2). Measurements of patient state index and mean arterial pressure were repeated after 20 (T3), and 40 (T4)min. RESULTS: There was a significant decrease between T0 and T1 in heart rate (80.5±11.6 vs. 75.9±14.4beats/min), MAP (105.8±21.9 vs. 78.9±18.4mmHg) and PSI (88.5±8.3 vs. 30.3±9.7) (all p<0.05). Mean arterial pressure decreased significantly after position change, and remained decreased, compared to T1. The overall analysis of patient state index values (T1-T4) showed no significant change; however, comparing only T1 and T2 resulted in a statically significant decrease in patient state index. There was a significant decrease in cerebral blood flow after beach chair position. CONCLUSION: Beach chair position was associated with a decrease in cerebral blood flow and patient state index values. Patient state index was affected by the gravitational change of the cerebral blood flow; however, both factors were not directly correlated to each other. Moreover, the decrease in patient state index value was transient and returned to normal values within 20min.

[Patient state index and cerebral blood flow changes during shoulder arthroscopy in beach chair position]. / Patient State Index e alterações do fluxo sanguíneo cerebral durante artroscopia do ombro em posição de cadeira de praia.

BACKGROUND AND OBJECTIVES: The aim of the study were to demonstrate the possible hemodynamic changes and cerebral blood flow alterations in patients who were positioned from supine to beach chair position; and to detect if the position change causes any cortical activity alteration as measured by the 4-channeled electroencephalography monitor. METHODS: 35 patients were included. Before the induction, mean arterial pressure and patient state index values were recorded (T0). After the intubation, doppler-ultrasonography of the patients' internal carotid and vertebral arteries were evaluated to acquire cerebral blood flow values from the formula. In supine position, mean arterial pressure, patient state index and cerebral blood flow values were recorded (T1) and the patient was positioned to beach chair position. After 5min all measurements were repeated (T2). Measurements of patient state index and mean arterial pressure were repeated after 20 (T3), and 40 (T4)min. RESULTS: There was a significant decrease between T0 and T1 in heart rate (80.5±11.6 vs. 75.9±14.4beats/min), MAP (105.8±21.9 vs. 78.9±18.4mmHg) and PSI (88.5±8.3 vs. 30.3±9.7) (all p<0.05). Mean arterial pressure decreased significantly after position change, and remained decreased, compared to T1. The overall analysis of patient state index values (T1-T4) showed no significant change; however, comparing only T1 and T2 resulted in a statically significant decrease in patient state index. There was a significant decrease in cerebral blood flow after beach chair position. CONCLUSION: Beach chair position was associated with a decrease in cerebral blood flow and patient state index values. Patient state index was affected by the gravitational change of the cerebral blood flow; however, both factors were not directly correlated to each other. Moreover, the decrease in patient state index value was transient and returned to normal values within 20min.