Use of Extracorporeal Membrane Oxygenation and Cerebral Oximetry in a Stage 1 Norwood Repair for Hypoplastic Left Heart Syndrome

The role of extracorporeal membrane oxygenation (ECMO) and its indications in stage I Norwood palliation are controversial. The decision to initiate ECMO and its timing remains difficult with no definitive cut?off points or evidence?based guidelines. It varies on a case?to?case basis. We report a case where the use of ECMO was beneficial after stage I Norwood palliation with severe ventricular dysfunction. The systemic?to?pulmonary artery shunt was kept open to balance the systemic and pulmonary circulations. Cerebral oximetry can be useful as an additional monitoring modality to guide management, monitor cerebral perfusion, and help detect cerebral steal.

The Use of Cerebral Oximetry in Cardiac Surgery: A Systematic Review and Meta?Analysis of Randomized Controlled Trials

High prevalence of cerebral desaturation is associated with postoperative neurological complications in cardiac surgery. However, the evidence use of cerebral oximetry by correcting cerebral desaturation in the reduction of postoperative complications remains uncertain in the literature. This systematic review and meta?analysis aimed to examine the effect of cerebral oximetry on the incidence of postoperative cognitive dysfunction in cardiac surgery. Databases of MEDLINE, EMBASE, and CENTRAL were searched from their inception until April 2021. All randomized controlled trials comparing cerebral oximetry and blinded/no cerebral oximetry in adult patients undergoing cardiac surgery were included. Observational studies, case series, and case reports were excluded. A total of 14 trials (n = 2,033) were included in this review. Our pooled data demonstrated that patients with cerebral oximetry were associated with a lower incidence of postoperative cognitive dysfunction than the control group (studies = 4, n = 609, odds ratio [OR]: 0.15, 95% confidence interval [CI]: 0.04 to 0.54, P = 0.003, I 2 = 88%; certainty of evidence = very low). In terms of postoperative delirium (OR: 0.75, 95%CI: 0.50–1.14, P = 0.18, I 2 = 0%; certainty of evidence = low) and postoperative stroke (OR: 0.81 95%CI: 0.37–1.80, P = 0.61, I 2 = 0%; certainty of evidence = high), no significant differences (P > 0.05) were reported between the cerebral oximetry and control groups. In this meta?analysis, the use of cerebral oximetry monitoring in cardiac surgery demonstrated a lower incidence of postoperative cognitive dysfunction. However, this finding must be interpreted with caution due to the low level of evidence, high degree of heterogeneity, lack of standardized cognitive assessments, and cerebral desaturation interventions.

Inadequacy of near-infrared spectroscopy cerebral oximetry monitoring for detecting neurological complication

Near-infrared spectroscopy (NIRS) cerebral oximetry is an established and standard monitoring modality for surgery under extracorporeal circulation with circulatory arrest. It helps to reduce the neurological complication, but in many instances, it becomes not only technically challenging but also is difficult to interpret and take corrective action based on the NIRS values. In this case study, we aimed to present the inadequacy of cerebral oximetry for detecting neurological complication.

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 pós-operatório em pacientes idosos: estudo piloto

Abstract 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 3rd 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.

Resumo Justificativa e objetivos: A disfunção cognitiva no pós-operatório é comum após cirurgia cardíaca. A perfusão cerebral adequada é essencial e a espectroscopia no infravermelho próximo (NIRS) pode medir a oxigenação cerebral. O objetivo deste estudo foi comparar a incidência de disfunção cognitiva no pós-operatório, precoce e tardio, em pacientes idosos tratados com monitoração convencional ou espectroscopia no infravermelho próximo. Métodos: Os pacientes submetidos à cirurgia coronariana, acima de 60 anos, foram incluídos e randomicamente alocados em dois grupos: grupo controle e grupo NIRS. O manejo dos pacientes no período perioperatório foi feito com NIRS no grupo NH e com abordagem convencional no grupo controle A bateria de testes foi feita antes da cirurgia, na primeira semana e no terceiro mês de pós-operatório. A bateria incluiu o desenho do relógio, a memória, a geração de uma lista de palavras, a sequência de dígitos e subtestes que exigem habilidades visuoespaciais.Disfunção cognitiva no pós-operatório foi definida como queda de um DP (desvio-padrão) da fase basal em dois ou mais testes. O teste U de Mann Whitney foi usado para comparação de medidas quantitativa e o teste exato do qui-quadrado para comparar dados quantitativos. Resultados: Vinte e um pacientes do grupo controle e 19 do grupo NIRS concluíram o estudo. Os dados demográficos e operacionais foram semelhantes. Na primeira semana, nove pacientes (45%) do GC e sete pacientes (41%) do grupo NIRS apresentaram disfunção cognitiva no pós-operatório. No terceiro mês, 10 pacientes (50%) foram avaliados como disfunção cognitiva no pós-operatório; a incidência foi de quatro (24%) no grupo NIRS (p = 0,055). O grupo que apresentou disfunção cognitiva no pós-operatório precoce e tardio teve uma permanência significativamente maior na UTI (1,74 + 0,56 vs. 2,94 + 0,95; p < 0,001; 1,91 + 0,7 vs. 2,79 + 1,05; p < 0,01) e permanência hospitalar mais longa (9,19 + 2,8 vs. 11,88 + 1,7; p < 0,01; 9,48 + 2,6 vs. 11,36 + 2,4; p < 0,05). Conclusão: Neste estudo piloto, a monitoração convencional e a espectroscopia no infravermelho próximo resultaram em taxas semelhantes de disfunção cognitiva no pós-operatório precoce. A disfunção cognitiva tardia tende a melhorar com espectroscopia no infravermelho próximo. Os declínios cognitivos precoces e tardios foram associados a internações prolongadas tanto em UTI quanto hospitalares.

Intraventricular hemorrhage after dural fistula embolization / Hemorragia intraventricular após embolização de fístula dural

Abstract Background and objectives: Dural arteriovenous fistulas are anomalous shunts between dural arterial and venous channels whose nidus is located between the dural leaflets. For those circumstances when invasive treatment is mandatory, endovascular techniques have grown to become the mainstay of practice, choice attributable to their reported safety and effectiveness. We describe the unique and rare case of a dural arteriovenous fistula treated by transarterial embolization and complicated by an intraventricular hemorrhage. We aim to emphasize some central aspects of the perioperative management of these patients in order to help improving the future approach of similar cases. Case report: A 59-year-old woman with a previously diagnosed Cognard Type IV dural arteriovenous fistula presented for transarterial embolization, performed outside the operating room, under total intravenous anesthesia. The procedure underwent without complications and the intraoperative angiography revealed complete obliteration of the fistula. In the early postoperative period, the patient presented with clinical signs of raised intracranial pressure attributable to a later diagnosed intraventricular hemorrhage, which conditioned placement of a ventricular drain, admission to an intensive care unit, cerebral vasospasm and a prolonged hospital stay. Throughout the perioperative period, there were no changes in the cerebral brain oximetry. The patient was discharged without neurological sequelae. Conclusion: Intraventricular hemorrhage may be a serious complication after the endovascular treatment of dural arteriovenous fistula. A close postoperative surveillance and monitoring allow an early diagnosis and treatment which increases the odds for an improved outcome.

Resumo Justificativa e objetivos: Fístulas arteriovenosas durais (FAVD) são comunicações anômalas entre os canais venosos e arteriais da dura-máter cujo centro está localizado entre os folhetos da dura-máter. Para as circunstâncias nas quais o tratamento invasivo é obrigatório, as técnicas endovasculares se tornaram os pilares da prática, escolha atribuível a relatos de sua segurança e eficácia. Descrevemos o caso único e raro de uma FAVD tratada por embolização transarterial (ETA) e complicada por uma hemorragia intraventricular (HIV). Nosso objetivo foi destacar alguns aspectos centrais do manejo perioperatório desses pacientes para ajudar a melhorar uma futura abordagem de casos semelhantes. Relato de caso: Paciente do sexo feminino, 59 anos, com diagnóstico prévio de FAVD tipo IV (Cognard), apresentou-se para ETA, realizada fora da sala de cirurgia soBanestesia venosa total. O procedimento transcorreu sem complicações, e a angiografia intraoperatória revelou obliteração completa da fístula. No período pós-operatório imediato, a paciente apresentou sinais clínicos de aumento da pressão intracraniana (PIC) atribuíveis a uma HIV posteriormente diagnosticada, o que condicionou a colocação de um dreno ventricular, internação em Unidade de Terapia Intensiva (UTI), vasoespasmo cerebral e internação hospitalar prolongada. Durante todo o período perioperatório, não houve alterações na oximetria cerebral. A paciente recebeu alta sem sequelas neurológicas. Conclusão: HIV pode ser uma complicação grave após o tratamento endovascular de FAVD. A observação e o monitoramento cuidadosos no pós-operatório permitem o diagnóstico precoce e o tratamento que aumenta as chances de um resultado melhor.

Comparative study between the effects of dexmedetomidine and propofol on cerebral oxygenation during sedation at pediatric cardiac catheterization.

Introduction: Nowadays, assessment of brain oxygen saturation, which is simply appliable and noninvasive method, can provide the anesthesia plans to be optimized according to the needs of the brain, which is the main target organ. Brain may be exposed to hypoxia due to supply-demand imbalance of oxygen not only in general anesthesia procedures but also in sedation practices. The aim of the study is to compare the effects of dexmedetomidine and propofol which are widely used agents for pediatric catheterization procedures on brain oxygen saturation using Fore-Sight. Material and Methods: A total of 44 patients undergoing diagnostic cardiac catheterization between 1 and 18 years old were included in the study. All patients, who were randomly divided into two groups, had ASA physical status I-II. In Group Propofol (Group P, n = 22),induction of sedation was made by midazolam (0.5 mg,iv) + propofol (1m/kg,iv), and in Group Dexmedetomidine (Group D, n = 22), induction of sedation was made by midazolam (0.5 mg,iv) +dexmedetomidine (1mcg/kg, iv). Throughout the sedation, cerebral tissue oxygen saturation (SctO2) was recorded by Fore-Sight in addition to routine monitoring. Results: There were no statistically significant differences between the groups in terms of demographic data, hemodynamic data and sedation scores. On other hand, statistically significant decreases in cerebral tissue oxygen saturation were detected especially at 5th and 10th minutes, in Group D, while cerebral oxygenation level did not decrease in Group P. Though, statistically significant difference was determined between two groups in terms of cerebral oxygen saturation, the obtained data was not interpreted as cerebral desaturation. Conclusion: As a conclusion, there was a statistically significant but clinically insignificant decrease in cerebral tissue oxygen saturation in dexmedetomidine group compared to propofol group. Although it does not seem to be important in hemodynamic stabilization, we assume that may cause problems for clinically unstable patients.

Oximetría cerebral: tres preguntas esenciales / Cerebral oximetry: Three questions to ask

Cerebral oximetry based on near-infrared spectroscopy can non-invasively measure hemoglobin oxygen saturation in mixed arterial, venous and capillary blood in the brain. In order to determine if this is a clinically desirable monitor, we need to answer three questions in order. The first question is if cerebral oximetry monitors an important aspect of physiology. The second question is if the physiology can be optimized based on this monitor. The third question is if the outcome can be improved based on cerebral oximetry-guided clinical care. In this review, we share our answers to these three questions.

La oximetría cerebral basada en la espectroscopia cercana al infrarrojo puede medir demanera no invasiva la saturación de oxígeno de la hemoglobina en la sangre mixta arterial, venosa y capilar en el cerebro. A fin de determinar si este monitor es deseable en la clínica, es preciso responder 3 preguntas, en su orden. La primera es si la oximetría cerebral monitorea un aspecto importante de la fisiología. La segunda es si se puede optimizar la fisiología con base en este monitor. La tercera es si se puede mejorar el desenlace mediante una intervención clínica basada en la oximetría cerebral. En esta revisión presentamos nuestras respuestas a estas 3 preguntas.

Effects of intravenously administered indocyanine green on near-infrared cerebral oximetry and pulse oximetry readings / 대한마취과학회지

BACKGROUND: Intravenously administered indocyanine green (ICG) may cause misreadings of cerebral oximetry and pulse oximetry in patients undergoing carotid endarterectomy under general anesthesia. The present study determined the effects of two different doses (12.5 mg vs. 25 mg) of ICG on regional cerebral tissue oxygen saturation (SctO2) and percutaneous peripheral oxygen saturation (SpO2). METHODS: Twenty-six patients receiving ICG for videoangiography were divided into two groups according to the dosage (12.5 mg and 25 mg, n = 13 in each group). Heart rate, arterial blood pressure, SctO2, and SpO2 were measured before and after an intravenous bolus administration of ICG. RESULTS: Following the dye administration, no changes in heart rate or arterial blood pressure were noted in either group. SctO2 was increased in both groups; however, the magnitude of the increase was greater (21.6 +/- 5.8% vs. 12.6 +/- 4.1%, P < 0.0001) and more prolonged (28.4 +/- 9.6 min vs. 13.8 +/- 5.2 min, P < 0.0001) in the 25 mg group than in the 12.5 mg group. In contrast, SpO2 was decreased in both groups; the magnitude of the decrease was greater in the 25 mg group than in the 12.5 mg group (4.0 +/- 0.8% vs. 1.6 +/- 1.0%, P < 0.0001). There were no differences in the time to reach the peak SctO2 or to reach the nadir SpO2 between the two groups. CONCLUSIONS: In patients given ICG for videoangiography, a 25 mg bolus results in a greater and more prolonged increase in SctO2 and a greater reduction in SpO2 than a 12.5 mg bolus, with no differences in the time to reach the peak SctO2 or to reach the nadir SpO2.

Severe tracheobronchial compression in a patient with Turner's syndrome undergoing repair of a complex aorto-subclavian aneurysm: Anesthesia perspectives.

We present a case of severe tracheobronchial compression from a complex aorto‑subclavian aneurysm in a patient with Turner’s syndrome undergoing open surgical repair. Significant airway compression is a challenging situation and requires careful preoperative preparation, maintenance of spontaneous breathing when possible, and consideration of having an alternative source of oxygenation and circulation established prior to induction of general anesthesia. Cardiopulmonary monitoring is essential for safe general anesthesia and diagnosis of unexpected intraoperative events.

Impact of monitoring cerebral oxygen saturation on the outcome of patients undergoing open heart surgery.

Aims and Objectives: We studied the usefulness of regional cerebral oxygen saturation (rSO 2 ) monitoring during cardiopulmonary bypass (CPB) and evaluated effects of cerebral oxygen desaturation on the postoperative neurological outcome. Materials and Methods: 100 patients were randomly allocated to either control or intervention group. In the control group rSO 2 was recorded continuously, but the attending anesthesiologist was blinded. In the intervention group specific interventions were initiated in case of cerebral desaturation. Neurocognitive testing was done using a simplified antisaccadic eye movement test (ASEM) and mini-mental state examination (MMSE). Data was analyzed using Chi-square test, and unpaired t-test. Results: In both the groups rSO 2 declined during CPB. The decrease in rSO 2 was significant ( P < 0.001) in the control group compared to the intervention group. In the intervention group the rSO 2 mainly responded to an increase in mean arterial pressure. The area under the curve below threshold rSO 2 was significantly more ( P < 0.0001) in the control group compared to intervention group and a significant decrease in the MMSE and ASEM scores occurred in control group at one week and three months postoperatively. Conclusions: Monitoring of rSO 2 during CPB can significantly decrease the incidence of postoperative neurocognitive decline.

Application of cerebral oximetry for a parturient with Takayasu's arteritis undergoing cesarean section: a case report / 대한마취과학회지

Takayasu's arteritis (TA) is a chronic inflammatory disease involving the aorta. Because TA sometimes involves cerebral arteries, anesthetic debates focus on cerebral monitoring. There is limited evidence as to which cerebral monitoring method is most adequate. Furthermore, there is insufficient evidence to determine which anesthetic technique is better for TA parturients. We experienced the case of a TA parturient who developed transient cerebral ischemia during cesarean section. The patient's TA involved her cerebral arteries, and her regional cerebral oxygen saturation (rSO2) was lower in the left side than in the right side. She complained of speech impairment, tinnitus, and stiffness of the posterior neck when the rSO2 levels dropped. The FloTrac/Vigileo(TM) system did not correlate with clinical symptoms, but the cerebral oximeter displayed the low oxygen saturation. We recommend the cerebral oximetry for cerebral monitoring in TA parturients who undergo cesarean sections, especially in hemodynamically unstable patients under regional anesthesia or unconscious patients under general anesthesia.

Congenital hypopituitarism: Monitoring after coronary artery bypass grafting.

Cardiovascular disease in patients with congenital hypopituitarism is not rare; however, there is a lack of reports referring to cardiac interventions in such patients. We present a 76-year-old man with complete pituitary hormone deficiency, who presented with recurrent events of unstable angina. He had a significant stenosis of the left anterior descending artery and he underwent off-pump coronary artery bypass. Our aim is to present the successful management of this patient with congenital hypopituitarism who underwent cardiac surgery and to review the relevant literature.

Cerebral oximetry monitoring during aortic arch aneurysm replacement surgery in Jehovah's Witness patient -A case report- / 대한마취과학회지

Anesthetic management for aortic arch aneurysm (AAA) surgery employing deep hypothermic circulatory arrest in a Jehovah's Witness (JW) patient is a challenge to anesthesiologist due to its complexity of procedures and their refusal of allogeneic transfusion. Even in the strict application of intraoperative acute normovolemic hemodilution (ANH) and intraopertive cell salvage (ICS) technique, prompt timing of re-administration of salvaged blood is essential for successful operation without allogeneic transfusion or ischemic complication of major organs. Cerebral oximetery (rSO2) monitoring using near infrared spectroscopy is a useful modality for detecting cerebral ischemia during the AAA surgery requiring direct interruption of cerebral flow. The present case showed that rSO2 can be used as a trigger facilitating to find a better timing for the re-administration of salvaged blood acquired during the AAA surgery for JW patient.

Cerebral oximetry monitoring during aortic arch aneurysm replacement surgery in Jehovah's Witness patient -A case report- / 대한마취과학회지

Anesthetic management for aortic arch aneurysm (AAA) surgery employing deep hypothermic circulatory arrest in a Jehovah's Witness (JW) patient is a challenge to anesthesiologist due to its complexity of procedures and their refusal of allogeneic transfusion. Even in the strict application of intraoperative acute normovolemic hemodilution (ANH) and intraopertive cell salvage (ICS) technique, prompt timing of re-administration of salvaged blood is essential for successful operation without allogeneic transfusion or ischemic complication of major organs. Cerebral oximetery (rSO2) monitoring using near infrared spectroscopy is a useful modality for detecting cerebral ischemia during the AAA surgery requiring direct interruption of cerebral flow. The present case showed that rSO2 can be used as a trigger facilitating to find a better timing for the re-administration of salvaged blood acquired during the AAA surgery for JW patient.

Emergence cerebral oxygen desaturation without hemodynamic compromise in pediatric patients / 대한마취과학회지

BACKGROUND: The regional cerebral oxygen saturation (rSO2) decreases significantly during ordinary anesthetic recovery in pediatric patients anesthetized with sevoflurane or desflurane. The present study examined the relationship between rSO2 and the clinical parameters associated with the degree of anesthetic recovery. METHODS: Twelve pediatric patients with American Society of Anesthesiologists physical status 1 were assigned randomly to receive anesthesia with sevoflurane or desflurane. All children underwent general anesthesia for minor surgery. After surgery, the rSO2, the age-adjusted MAC fraction of anesthetic concentration (F(E)), and the bispectral index (BIS) were recorded over a 10-minute period. The correlations between rSO2 and candidate predictors, such as F(E), BIS, anesthetic, and duration of anesthesia, were analyzed. RESULTS: All children recovered uneventfully. The lowest observed rSO2 reached 63% and the maximum decrease in rSO2 was 24%. The mean blood pressure and heart rate were maintained within clinical ranges. The decrease in rSO2 correlated positively with the F(E) (r = 0.25, P = 0.00) and the duration of anesthesia (r = 0.24, P = 0.01), and inversely with the use of sevoflurane (r = -0.30, P = 0.00). CONCLUSIONS: Despite normal parameters, cerebral desaturation occurred during the emergence of ordinary general anesthesia even without hemodynamic compromise or arterial desaturation. Cerebral desaturation might be associated with the degree of anesthetic recovery and the use of sevoflurane.

Hypocapnia Attenuates, and Nitrous Oxide Disturbs the Cerebral Oximetric Response to the Rapid Introduction of Desflurane

The aim of this study was to develop a nonlinear mixed-effects model for the increase in cerebral oximetry (rSO2) during the rapid introduction of desflurane, and to determine the effect of hypocapnia and N2O on the model. Twelve American Society of Anesthesiologist physical status class 1 and 2 subjects were allocated randomly into an Air and N2O group. After inducing anesthesia, desflurane was then increased abruptly from 4.0 to 12.0%. The PET(CO2), PET(DESF) and rSO2 were recorded at 12 predetermined periods for the following 10 min. The maximum increase in rSO2 reached +24-25% during normocapnia. The increase in rSO2 could be fitted to a four parameter logistic equation as a function of the logarithm of PET(DESF). Hypocapnia reduced the maximum response of rSO2, shifted the EC50 to the right, and increased the slope in the Air group. N2O shifted the EC50 to the right, and reduced the slope leaving the maximum rSO2 unchanged. The N2O-effects disappeared during hypocapnia. The cerebrovascular reactivity of rSO2 to CO2 is still preserved during the rapid introduction of desflurane. N2O slows the response of rSO2. Hypocapnia overwhelms all the effects of N2O.

Perioperative cerebral infarct during cardiac surgery and changes in jugular venous O2 saturation and cerebral oximetry using near-infrared spectroscopy: A case report / 대한마취과학회지

Despite reductions in surgical mortality, neurologic sequelae remain a devastating complication after cardiac surgery with cardiopulmonary bypass. Neurologic complications may be induced by a massive air embolism during cardiopulmonary bypass, even with extensive monitoring. This report describes a patient who had a fatal cerebral infarct during aortic valve and ascending aorta replacement surgery. We monitored jugular venous O2 saturation (SjvO2) and cerebral oximetry using near-infrared spectroscopy in the perioperative period. The operation and anesthesia were uneventful until the deep hypothermic total arrest for the replacement of the ascending aorta. However, restarting the cardiopulmonary bypass after deep hypothermic total arrest produced a brief (less than 10 seconds) but large amount of air in the root cannula. At this time, although cerebral oximetry did not show any changes, the SjvO2 decreased to 21% for about 3 minutes and then normalized. At 8 hours after surgery, the patient showed seizures and severe edema in both cerebral hemispheres on the MRI. The patient died 21 days after surgery.

Response of cerebral oximetry to increase in alveolar concentration of desflurane: effect of remifentanil and cerebrovascular CO2 reactivity / 대한마취과학회지

BACKGROUND: It is known that sympathetic stimulation and increase in cerebral blood flow velocity can be induced by desflurane. Cerebral oxygen balance could be disturbed during desflurane induction. Aim of this study was to elucidate that cerebral oxygen imbalance induced by desflurane mask induction can be reduced by combination of remifentanil and hypocapnia. METHODS: Twenty ASA 1-2 subjects were allocated randomly into 5 groups divided by concentration of remifentanil (0.0, 0.5, 1.0, 1.5, and 2.0 ng/ml). After confirmation of attaining proposed concentration of remifentanil, propofol and vecuronium were administered and mechanical ventilation was done with 8% desflurane with facial mask. Subsequently, changes in regional cerebral oxygen saturation (DeltarSO2), arterial blood pressure, heart rate, cardiac index, estimated alveolar concentration of desflurane (PDESF), and end-tidal concentration of carbon dioxide (PETCO2) were recorded for the following 10 minutes. According to concentration of desflurane and remifentanil, DeltarSO2 and hemodynamic factors were checked. RESULTS: During desflurane induction, changes in cerebral oximetry reached up to +10% (6 [first quartile], 13 [third quartile]). Arterial blood pressure, heart rate, and cardiac index were changed within clinical ranges. The DeltarSO2 showed S-shaped increasing pattern according to increasing PDESF. Hypocapnia and concentration of remifentanil reduced the maximum DeltarSO2 (P = 0.0046, P = 0.0060). Hypocapnia also shifted the curve to left (P = 0.0001). CONCLUSIONS: During 8% desflurane induction, regional cerebral oxygen saturation (rSO2) increases maximum +25%. Hypocapnia and use of remifentanil can reduce the increase in regional cerebral oxygen saturation.

Retrograde Aortic Dissection during Ascending Aortic Aneurysm Surgery : A case report

Aortic dissection during cardiopulmonary bypass for aortic aneurysm surgery is a rare complication. If unrecognized in early time, it would be a fatal consequence. Neurological sequelae remain a well-recognized complication of cardiac surgery. Monitoring of cerebral oxygenation may be a useful technique for identifying vulnerable periods for the development of neurological injury. We report the experience of the decreasing left radial blood pressure and left rSO2 which caused by retrograde aortic dissection during the ascending aortic aneurysm replacement surgery.

The comparison of cerebral oximetry and somatosensory evoked potential for monitoring carotid endarterectomy / 解放军医学杂志

Objective To compare cerebral oximetry(rSO 2 %)and somatosensory evoked potential (N 35 ) in their accuracy in monitoring cerebral perfusion during carotid endarterectomy procedure under general anesthesia. Methods Ten patients (6 males, 4 females), scheduled for selective carotid endarterectomy, were enrolled in the study. Their rSO 2 %and N 35 were also continuously monitored and recorded during perioperative periods. The patients' cognitive function was evaluated at the same time. The MAP, HR, SpO 2 were continuously monitored during operation. Results There was a significant difference in rSO 2 % between that at the period of elamping and that at the period of declamping of the carotid artery. No patients suffered from cognition dysfunction during perioperative period. Conclusion With comparison to the amplitude of N 35 it was rSO 2 % which was earlier to show alteration in cerebral perfusion in case of cerebral oxygen deficit. In monitoring cerebral perfusion, rSO 2 % was better than N 35