Regional Cerebral Oxygen Saturation Monitoring Research Articles

Optimization of cerebral oxygenation based on regional cerebral oxygen saturation monitoring during carotid endarterectomy: a Phase III multicenter, double-blind randomized controlled trial

BackgroundWhether the optimization of cerebral oxygenation based on regional cerebral oxygen saturation (rSO2) monitoring reduces the occurrence of cerebral ischemic lesions is unknown. MethodsThis multicenter, randomized, controlled trial recruited adults admitted for scheduled carotid endarterectomy. Patients were randomized between the standard of care or optimization of cerebral oxygenation based on rSO2 monitoring using near-infrared spectroscopy. In the intervention group, in case of a decrease in rSO2 in the intervention, the following treatments were sequentially recommended: (1) increasing oxygenotherapy, (2) reducing the tidal volume, (3) legs up-raising, (4) performing a fluid challenge and (5) initiating vasopressor support. The primary endpoint was the number of new cerebral ischemic lesions detected using magnetic resonance imaging pre- and postoperatively. Secondary endpoints included new neurological deficits and mortality on day 120 after surgery. ResultsAmong the 879 patients who were randomized, 665 (75.7%) were men. There was no statistically significant difference between groups for the mean number of new cerebral ischemic lesions per patient up to 3 days after surgery: 0.35 (±1.05) in the standard group vs. 0.58 (±2.83), in the NIRS group; mean difference, 0.23 [95% CI, −0.06 to 0.52]; estimate, 0.22 [95% CI, −0.06 to 0.50]. New neurological deficits up to day 120 after hospital discharge were not different between the groups: 15 (3,39%) in the standard group vs. 42 (5,49%) in the NIRS group; absolute difference, 2,10 [95% CI, −0,62 to 4,82]. There was no significant difference between groups for the median [IQR] hospital length of stay: 4.0 [4.0–6.0] in the standard group vs. 5.0 [4.0–6.0] in the NIRS group; mean difference, −0.11 [95% CI, −0.65 to 0.44]. The mortality rate on day 120 was not different between the standard group (0.68%) vs. the NIRS group (0.92%); absolute difference = 0.24% [95% CI, −0.94 to 1.41]. ConclusionsAmong patients undergoing carotid endarterectomy, optimization of cerebral oxygenation based on rSO2 did not reduce the occurrence of cerebral ischemic lesions postoperatively compared with controlled hypertensive therapy. Trial registrationClinicalTrials.gov identifier: NCT01415648.

Intraoperative application of regional cerebral oxygen saturation monitoring for geriatric patients in China: a survey.

Regional cerebral oxygen saturation (rSO2) monitoring is a real-time and non-invasive technique for estimating the balance of regional cerebral oxygen supply and consumption. Despite the growing popularity of this monitoring technique, data regarding outcome benefits remain sparse and contradictory. This study was conducted to explore the popularity and understanding of cerebral oxygen saturation monitoring during anesthesia in geriatric patients. An online self-report questionnaire was distributed in March 2021 to various hospitals in China for dissemination to anesthesiologists. Questions surveyed cerebral oximetry equipment and utilization, demographics, and clinical practice of participants. In total, 447 anesthesiologists responded. Of these, 301 (67.3%) respondents reported that their hospitals were equipped with cerebral oximetry, which 274 anesthesiologists use during anesthesia. A high percentage of anesthesiologists chose to monitor rSO2 during cardiac surgery (77.4%, n = 212) and neurosurgery (40.5%, n = 111). Most anesthesiologists agreed that a 30% reduction from the rSO2 baseline requires intervention to avoid cerebral ischemia, mainly via elevating arterial pressure and fraction of inspired oxygen (FiO2). Of those without cerebral oximetry, 138 of 146 (94.5%) anesthesiologists were willing to monitor rSO2. In addition, 291 respondents believed that cerebral oxygen monitoring would help prevent postoperative cognitive dysfunction. Our survey indicated that the prevalence of cerebral oximetry remains relatively low, while almost all anesthesiologists expressed their willingness to use rSO2 monitoring in geriatric anesthesia. Heterogeneity in clinical practice was identified, indicating relevant knowledge gaps that should encourage further clinical research to optimize treatment.

Cerebral oximetry and autoregulation monitoring in shock patients

Background: Data on regional cerebral oxygen saturation (rSO2) and cerebral autoregulation monitoring in shock patients are limited. This study aimed to find the optimal range of rSO2 and cerebral oximetry index (COx), an autoregulation index correlated with adequate tissue perfusion determined by standard clinical and laboratory assessment. Method: We plan to monitor cerebral oximetry using near-infrared spectroscopy in shock patients admitted to the medical intensive care unit (MICU) at Siriraj Hospital. The rSO2 are continuously recorded for 72 hours [48] after admission or 24 hours after cessation of vasopressor infusion. The COx is calculated from the correlation coefficient between rSO2 and MAP. Data on patient demographics, treatments, physiologic parameters, and outcomes are recorded. The primary objective is to identify the optimal rSO2 and COx correlated with adequate tissue perfusion assessed by the current standard method. Adequate tissue perfusion as is defined as MAP ≥65 mmHg and two of the following criteria: urine ≥0.5 ml/kg/hour, capillary refill time ≤3 seconds, improvement in consciousness, lactate reduction ≥10% in 1 hour, serum lactate <2 mmol/L, or central venous oxygen saturation (ScVO2) ≥70%. Since the optimal values of rSO2 and COx in shock patients are unknown, we are unable to perform the sample size calculation. Thus, for this study, we plan to collect data on rSO2 and COx in 30 patients. Hypothesis: We hypothesize that the values of rSO2 and COx are different between patients with adequate and inadequate tissue perfusion. Ethics statement: The study was reviewed and approved by the Human Research Protection Unit of Siriraj Hospital, Mahidol University (certificate of approval no. si 410/2022).

Effects of regional cerebral oxygen saturation monitoring on postoperative cognitive dysfunction in older patients: a systematic review and meta-analysis

Background:Postoperative cognitive dysfunction (POCD) is common after surgery and anesthesia, particularly in older patients. It has been reported that regional cerebral oxygen saturation (rSO2) monitoring potentially influences the occurrence of POCD. However, its role in the prevention of POCD remains controversial in older patients. Additionally, the quality of evidence on this topic is still relatively poor.Methods:The electronic databases PubMed, EMBASE, Web of Science, and Cochrane Library were systematically searched using the indicated keywords from their inception to June 10, 2022. We limited our meta-analysis to randomized controlled trials (RCTs) that assessed the effects of rSO2 monitoring on POCD in older patients. Methodological quality and risk of bias were assessed. The primary outcome was the incidence of POCD during hospitalization. The secondary outcomes were postoperative complications and the length of hospital stay (LOS). Odds ratios (OR) and 95% confidence intervals (CI) were calculated to determine the incidence of POCD and postoperative complications. The standardized mean difference (SMD) instead of the raw mean difference and 95% CI were calculated for LOS.Results:Six RCTs, involving 377 older patients, were included in this meta-analysis. The incidence of POCD ranges from 17 to 89%, with an overall prevalence of 47% in our pooled analysis. Our results demonstrated that rSO2-guided intervention could reduce the incidence of POCD in older patients undergoing non-cardiac surgery (OR, 0.44; 95% CI, 0.25 to 0.79; P = 0.006) rather than cardiac surgery (OR, 0.69; 95% CI, 0.32 to 1.52; P = 0.36). Intraoperative rSO2 monitoring was also associated with a significantly shorter LOS in older patients undergoing non-cardiac surgery (SMD, -0.93; 95% CI, -1.75 to -0.11; P = 0.03). Neither the incidence of postoperative cardiovascular (OR, 1.12; 95% CI, 0.40 to 3.17; P = 0.83) nor surgical (OR, 0.78; 95% CI, 0.35 to 1.75; P = 0.54) complications were affected by the use of rSO2 monitoring.Conclusion:The use of rSO2 monitoring is associated with a lower risk of POCD and a shorter LOS in older patients undergoing non-cardiac surgery. This may have the potential to prevent POCD in high-risk populations. Further large RCTs are still warranted to support these preliminary findings.

Cerebral Oxygenation during Neonatal Intubation with Nasal High Flow: A Sub-Study of the SHINE Randomized Trial

Introduction: Nasal high flow (nHF) improves the likelihood of successful neonatal intubation on the first attempt without physiological instability. The effect of nHF on cerebral oxygenation is unknown. The aim of this study was to compare cerebral oxygenation during endotracheal intubation in neonates receiving nHF and those receiving standard care. Methods: A sub-study of a multicentre randomized trial of nHF during neonatal endotracheal intubation. A subset of infants had near-infrared spectroscopy (NIRS) monitoring. Eligible infants were randomly assigned to nHF or standard care during the first intubation attempt. NIRS sensors provided continuous regional cerebral oxygen saturation (rScO₂) monitoring. The procedure was video recorded, and peripheral oxygen saturation and rScO₂ data were extracted at 2-second intervals. The primary outcome was the average difference in rScO₂ from baseline during the first intubation attempt. Secondary outcomes included average rScO₂ and rate of change of rScO₂. Results: Nineteen intubations were analyzed (11 nHF; 8 standard care). Median (interquartile range [IQR]) postmenstrual age was 27 (26.5–29) weeks, and weight was 828 (716–1,135) g. Median change in rScO₂ from baseline was −1.5% (−5.3 to 0.0) in the nHF group and −9.4% (−19.6 to −4.5) in the standard care group. rScO₂ fell more slowly in infants managed with nHF compared with standard care: median (IQR) rScO₂ change −0.08 (−0.13 to 0.00) % per second and −0.36 (−0.66 to −0.22) % per second, respectively. Conclusions: In this small sub-study, regional cerebral oxygen saturation was more stable in neonates who received nHF during intubation compared with standard care.

Cerebral oximetry using near-infrared spectroscopy (NIRS) in cardiovascular and thoracic anaesthesia: A review

Near-infrared Spectroscopy (NIRS) has a well-established role in cardiovascular and thoracic anaesthesia, and its use is increasing in popularity. Regional cerebral oxygen saturation monitoring may be helpful for patients who are at risk for cerebral ischemia. During cardiac induction, there is a risk of developing complications like arrhythmias, hypotension, cardiac arrest, ST-segment changes, acute low cardiac output, pulmonary hypertension, diastolic dysfunction, valve dysfunction, residual shunts, or residual obstruction of ventricular outflow tracts, brain injuries, etc; where cerebral oxygen saturation is affected. These complications are multifactorial due to the use of heartlung machines as a result of the issues of aorto-pulmonary shunts, pathophysiological changes in the cardiovascular system, hypothermia, circulatory arrest (DHA), prolonged CPB time, specific surgical technique, anaesthesia, and different medications. The non-invasive, compact, continuous measurement technology known as NIRS tracks oxygenation in the brain, muscle, and other organs. In real time, it senses small changes in tissue oxygenation. We hypothesized that NIRS would be a useful technique for detecting increased susceptibility to ischemic neurologic harm. It could be a helpful technique for tracking brain oxygenation when jugular bulb oxygen saturation monitoring is not an option. NIRS is a useful tool for predicting critical events and figuring out how to handle them for a better outcome and faster discharge.

Can regional cerebral oxygen saturation monitoring during circulatory arrest time predict postoperative neurological dysfunction in patients undergoing surgical pulmonary thromboendarterectomy? Useful index for short- and long-term outcomes.

A hypothermic circulatory arrest is usually used to correct thoracic aorta pathologies. The emergency treatment of acute type A aortic dissection and elective repair of aortic arch pathologies are the most common indications for using hypothermic circulatory arrest. A hypothermic circulatory arrest can also be used for surgical pulmonary thromboendarterectomy in patients with chronic thromboembolic pulmonary hypertension. Intervals with total circulatory arrest offer a clear surgical field for thrombus and emboli removal from the pulmonary artery branches. The price to pay for intermittent circulatory arrest during pulmonary thromboendarterectomy is postoperative neurological dysfunction due to brain hypothermia and hypoperfusion. A noninvasive method for cerebral monitoring during cardiac surgery is real-time regional cerebral oxygen saturation (rSO2 ). Liu et al. report that continuous monitoring of rSO2 during surgical pulmonary thromboendarterectomy may reduce the long cerebral hypoperfusion time and prevent postoperative neurological dysfunction.

Balloon Test Occlusion of Internal Carotid Artery in Recurrent Nasopharyngeal Carcinoma Before Endoscopic Nasopharyngectomy: A Single Center Experience.

ObjectivesEndoscopic nasopharyngectomy (ENPG) is a promising way in treating recurrent nasopharyngeal carcinoma (rNPC), but sometimes may require therapeutic internal carotid artery (ICA) occlusion beforehand. Balloon test occlusion (BTO) is performed to evaluate cerebral ischemic tolerance for ICA sacrifice. However, absence of neurological deficits during BTO does not preclude occur of delayed cerebral ischemia after permanent ICA occlusion. In this study, we evaluate the utility of near-infrared spectroscopy (NIRS) regional cerebral oxygen saturation (rSO2) monitoring during ICA BTO to quantify cerebral ischemic tolerance and to identify the valid cut-off values for safe carotid artery occlusion. This study also aims to find out angiographic findings of cerebral collateral circulation to predict ICA BTO results simultaneously.Material and Methods87 BTO of ICA were performed from November 2018 to November 2020 at authors’ institution. 79 angiographies of collateral flow were performed in time during BTO and classified into several Subgroups and Types according to their anatomic and collateral flow configurations. 62 of 87 cases accepted monitoring of cerebral rSO2. Categorical variables were compared by using Fisher exact tests and Mann–Whitney U tests. Receiver operating characteristic curve analysis was used to determine the most suitable cut-off value.ResultsThe most suitable cut-off △rSO2 value for detecting BTO-positive group obtained through ROC curve analysis was 5% (sensitivity: 100%, specificity: 86%). NIRS rSO2 monitoring wasn’t able to detect BTO false‐negative results (p = 0.310). The anterior Circle was functionally much more important than the posterior Circle among the primary collateral pathways. The presence of secondary collateral pathways was considered as a sign of deteriorated cerebral hemodynamic condition during ICA BTO. In Types 5 and 6, reverse blood flow to the ICA during BTO protected patients from delayed cerebral ischemia after therapeutic ICA occlusion (p = 0.0357). In Subgroup IV, absence of the posterior Circle was significantly associated with BTO-positive results (p = 0.0426).ConclusionAngiography of cerebral collateral circulation during ICA BTO is significantly correlated with ICA BTO results. Angiographic ICA BTO can be performed in conjunction with NIRS cerebral oximeter for its advantage of being noninvasive, real-time, cost-effective, simple for operation and most importantly for its correct prediction of most rSO2 outcomes of ICA sacrifice. However, in order to ensure a safe carotid artery occlusion, more quantitative adjunctive blood flow measurements are recommended when angiography of cerebral collateral circulation doesn’t fully support rSO2 outcome among clinically ICA BTO-negative cases.

Effect of hemoglobin content on cerebral oxygen saturation during surgery for scoliosis in pediatric patients

BackgroundAlthough regional cerebral oxygen saturation (rScO2) monitoring has been widely used in clinical practice, the relationship between hemoglobin (dHB) content and rScO2 is incompletely understood. The aim of this study was to analyze the effect of hemoglobin content on rScO2 in pediatric patients undergoing general anesthesia for correction of scoliosis.MethodsNinety-two pediatric patients aged 3 to 14 years undergoing scoliosis correction surgery were enrolled. Continuous monitoring of bilateral regional cerebral oxygen saturation by near-infrared spectroscopy (NIRS, CASMED, USA) was performed after entering the operation room. rScO2 was recorded when the patients entered the operating room (T0, baseline), after anesthesia induced intubation (T1), and after radial artery puncture (T2). The lowest value of rScO2 during surgery was also recorded. The arterial blood pressure (ABP), heart rate (HR), pulse oxygen saturation (SpO2), end tidal carbon dioxide partial pressure (PetCO2) were continuously recorded. Patients were classified as low rScO2 or high rScO2 group according to whether the lowest intraoperative rScO2 was 15% lower than the baseline value. An analysis and comparison of differences in hemoglobin content in these two groups was carried out.ResultsThe preoperative hemoglobin-postoperative hemoglobin of patients in the high rScO2 group was significantly lower than that in the low rScO2 group (t = − 7.86, p < 0.01), the amount of bleeding during the operation was also less than that in the low rScO2 group (t = − 6.05, p < 0.01), and the systolic pressure of patients was higher than that in the low rScO2 group (t = 4.27, p < 0.01).ConclusionsThe decrease in hemoglobin level which occurs during surgery leads to a decrease in cerebral oxygen saturation. In order to ensure patient safety during surgery, it is necessary to carry out volume management and appropriate transfusion and fluid replacement in a timely manner.Trial registrationChinese Clinical Trial Registry, ChiCTR1800016359. Registered 28 May 2018.

Effects of electroencephalography and regional cerebral oxygen saturation monitoring on perioperative neurocognitive disorders: a systematic review and meta-analysis

BackgroundPerioperative neurocognitive disorders (PND) is a common postoperative complication including postoperative delirium (POD), postoperative cognitive decline (POCD) or delayed neurocognitive recovery. It is still controversial whether the use of intraoperative cerebral function monitoring can decrease the incidence of PND. The purpose of this study was to evaluate the effects of different cerebral function monitoring (electroencephalography (EEG) and regional cerebral oxygen saturation (rSO2) monitoring) on PND based on the data from randomized controlled trials (RCTs).MethodsThe electronic databases of Ovid MEDLINE, PubMed, EMBASE, Cochrane Library database were systematically searched using the indicated keywords from their inception to April 2020. The odds ratio (OR) or mean difference (MD) with 95% confidence interval (CI) were employed to analyze the data. Heterogeneity across analyzed studies was assessed with chi-square test and I2 test.ResultsTwenty two RCTs with 6356 patients were included in the final analysis. Data from 12 studies including 4976 patients were analyzed to assess the association between the EEG-guided anesthesia and PND. The results showed that EEG-guided anesthesia could reduce the incidence of POD in patients undergoing non-cardiac surgery (OR: 0.73; 95% CI: 0.57–0.95; P = 0.02), but had no effect on patients undergoing cardiac surgery (OR: 0.44; 95% CI: 0.05–3.54; P = 0.44). The use of intraoperative EEG monitoring reduced the incidence of POCD up to 3 months after the surgery (OR: 0.69; 95% CI: 0.49–0.96; P = 0.03), but the incidence of early POCD remained unaffected (OR: 0.61; 95% CI: 0.35–1.07; P = 0.09). The remaining 10 studies compared the effect of rSO2 monitoring to routine care in a total of 1380 participants on the incidence of PND. The results indicated that intraoperative monitoring of rSO2 could reduce the incidence of POCD (OR 0.53, 95% CI 0.39–0.73; P < 0.0001), whereas no significant difference was found regarding the incidence of POD (OR: 0.74; 95% CI: 0.48–1.14; P = 0.17).ConclusionsThe findings in the present study indicated that intraoperative use of EEG or/and rSO2 monitor could decrease the risk of PND.Trial registrationPROSPREO registration number: CRD42019130512.

Regional Cerebral Oxygen Saturation Monitoring during Spinal Surgery in Order to Identify Patients at Risk for Cerebral Desaturation

Background: Near infrared spectroscopy (NIRS) devices are non-invasive and monitor cerebral oxygen saturation (rScO2) continuously. NIRS interventional protocol is available in order to avoid hypoxic brain injury. Methods: We recruited patients scheduled for spinal surgery (n = 44). rScO2 was monitored throughout the surgery using INVOS 4100 cerebral oximeter. If the rScO2 values dropped more than 20% below baseline, or there was an absolute drop to below 50%, NIRS interventional protocol was followed. Results: In two patients rScO2 decreased by more than 20% from baseline values. In one patient rScO2 decreased to below 50%. NIRS protocol was initiated. As the first step, correct head position was verified–in one patient rScO2 increased above the threshold value. In the two remaining patients, mean arterial pressure was raised by injecting Ephedrin boluses as the next step. rScO2 raised above threshold. Patients with desaturation episodes had longer medium time of the operation (114 ± 35 versus 200 ± 98 min, p = 0.01). Pearson’s correlation showed a negative correlation between rScO2 and duration of operation (r = −0.9, p = 0.2). Receiver operating characteristic curve analysis showed blood loss to be a strong predictor for possible cerebral desaturation (Area under the curve (AUC): 0.947, 95%CI: 0.836–1.000, p = 0.04). Conclusion: Patients with higher blood loss might experience cerebral desaturation more often than spinal surgery patients without significant blood loss.

Cerebral oxygenation monitoring during resuscitation by emergency medical technicians: a prospective multicenter observational study.

AimTo assess the feasibility and predictive ability of regional cerebral oxygen saturation monitoring during cardiopulmonary resuscitation by emergency medical technicians.MethodsThis prospective observational study included 33 cardiac arrest patients who received cardiopulmonary resuscitation in a prehospital setting. Patients were connected to a near‐infrared spectrometer through two disposable probes immediately after entering the ambulance. The monitor, which showed regional cerebral oxygen saturation readings, was obscured by covering it with a sheet of paper. Regional cerebral oxygen saturation was measured continuously until hospital arrival. Outcome variables included the prehospital return of spontaneous circulation, survival to hospital admission, and survival at 90 days.ResultsFor patients who survived >90 days after hospital admission (n = 2), the mean regional cerebral oxygen saturation values upon ambulance and hospital arrival were 24% and 60%, respectively; for patients who did not survive (n = 31), the mean regional cerebral oxygen saturation values were 15% and 17%, respectively. Regional cerebral oxygen saturation values increased to a greater extent between ambulance arrival and hospital arrival in patients who survived >90 days (median, 36%; interquartile range, 32–40%) than in those who did not survive (0; 0–6%; P = 0.07). Additionally, regional cerebral oxygen saturation values were not related to the prehospital return of spontaneous circulation or survival to hospital admission.ConclusionRegional cerebral oxygen saturation could be monitored during resuscitation by emergency medical technicians, and it can be used during physiological monitor‐guided cardiopulmonary resuscitation.

Prognostic Value of Tissue Oxygen Monitoring and Regional Cerebral Oxygen Saturation Monitoring and Their Correlation in Neurological Patients with Sepsis: A Preliminary, Prospective, Observational Study.

There is paucity of literature on the prognostic value of tissue oxygen saturation (StO2) and regional cerebral oxygen saturation (rSO2) in neurological patients with sepsis. In this preliminary study, we investigated the prognostic value of StO2 and rSO2 in a group of neurological patients and correlated StO2 and rSO2 with hemodynamic and metabolic parameters. This preliminary, prospective observational study was conducted in 45 adult neurological patients admitted to intensive care unit. Once a diagnosis of sepsis or septic shock was established, parameters of oxygenation (StO2, rSO2, central venous oxygen saturation [ScvO2]), serum lactate, illness severity scores (Acute Physiology and Chronic Health Evaluation score, Sequential Organ Failure Assessment score, Glasgow Coma Scale) were recorded at 0, 6, 12, 24, 36, and 48 hours, and once daily thereafter. Outcomes were in-hospital mortality attributable to sepsis and the Glasgow outcome score at hospital discharge. There was a moderately positive correlation between StO2 and rSO2 at baseline (r=0.599; P=0.001). StO2, illness severity scores and serum lactate, but not rSO2, were significantly different between survivors (n=29) and nonsurvivors (n=16) at baseline and during the first 48 hours. An rSO2 of 62.5% had a sensitivity of 83% and specificity of 67% to differentiate survivors and nonsurvivors of septic shock at 48 hours. StO2 had a higher correlation with ScvO2 and serum lactate than rSO2. StO2 prognosticates survival and favorable/unfavorable outcomes in neurological patients with sepsis. The role of rSO2 in predicting survival in milder form of sepsis is doubtful.

Anaesthetic management in endovascular total aortic arch repair via needle-based in situ fenestration: a case series of 14 patients.

ObjectiveEndovascular total aortic arch repair (ETAAR) via needle-based in situ fenestration (ISF) is a major challenge for anaesthesiologists because of haemodynamic instability and the risk of cerebral hypoxia. We herein summarise our experience with anaesthetic management of patients who underwent this procedure.MethodsFourteen patients who underwent ETAAR via ISF for arch pathologies involving the major supra-arch branches were included. Regional cerebral oxygen saturation was measured to monitor cerebral perfusion. Partial extracorporeal circulation (EC) support from the right common femoral vein to the right axillary artery was introduced to provide cerebral perfusion.ResultsDuring ISF, vessel rupture occurred in three patients and ventricular fibrillation occurred in one patient. The regional cerebral oxygen saturation significantly decreased during the potential risk period for cerebral ischaemia. Establishment of EC effectively prevented cerebral ischaemia.ConclusionsDuring ETAAR, the risks of haemodynamic instability caused by the procedure and vessel rupture during ISF need to be overcome. Partial EC ensured good cerebral protection in our study, and regional cerebral oxygen saturation monitoring may help to reduce the rate of desaturation.

Abstract 459: The TripleCPR 16 Study: Does Rhythm Truly Needed to Be Checked Every 2 Minutes in Cardiopulmonary Arrest Patients?

Purpose: Current guidelines recommend rhythm checks every 2 minutes during CPR, but evidence for this recommendation is insufficient. Recent reports identified regional cerebral oxygen saturation (rSO 2 ) monitoring as useful in detecting ROSC and that coronary and cerebral perfusion decrease with the 2-minute rhythm check. On the basis of our previous study, we began the TripleCPR 16 study, which omits 2-minute rhythm checks because stopping chest compression to check rhythm may increase cerebral damage and decrease the ROSC. Methods: The multicenter, prospective TripleCPR 16 study began in January 2017. The inclusion criterion is a cardiopulmonary arrest patient aged ≥16 years with a non-shockable rhythm on hospital arrival. Subjects are divided into 3 groups based on their mean cerebral rSO 2 value in the first minute of arrival: ≥50%, &lt;50% to 40%, and &lt;40%. Continuous mechanical chest compression is performed on all subjects for 16 minutes or until their rSO 2 value exceeds the initial value by 10%, 20%, or 35%, respectively. We are comparing the TripleCPR 16 study results with our previous hospital data obtained from 86 patients with non-shockable rhythm who underwent every 2-minute rhythm checks and mechanical chest compression. Result: Currently, 218 patients are registered. Rates of ROSC were 34.9% for these patients and 39.5% for the previous 86 patients (p=0.51). There were no severe adverse events. Subanalysis of the data of Osaka University Hospital alone showed no significant increase of rSO 2 value in the 48 patients with non-sonographic cardiac activity and 26 patients with Stanford type A aortic dissection diagnosed by CT scan, and only two patient in each group achieved ROSC. When excluding the patients with Stanford type A aortic dissection, rates of ROSC was 47.8% for the patients in this study and 39.0% for the previous 86 patients (p=0.26). Conclusion: The TripleCPR 16 study is ongoing without severe adverse events. In the patients with non-sonographic cardiac activity or Stanford type A aortic dissection, rSO 2 values did not increase and it was difficult to achieve ROSC. A simpler CPR protocol could be devised that omits the 2-minute rhythm check in patients with a non-shockable rhythm.

Application of bilateral regional cerebral oxygen saturation monitoring in patients with acute ischemic stroke undergoing endovascular thrombectomy

Objective To evaluate cerebral perfusion with the bilateral cerebral oxygen saturation(rSO2) monitoring in patients with acute ischemic stroke (AIS) after endovascular thrombectomy (EVT). Methods Patients with AIS who received EVT, aging over 18 with American Society of Anesthesiologists(ASA) grade Ⅰ-Ⅳ were selected for this study. There were total 24 patients enrolled in this observational study. They were divided in two groups according to extent of thrombolysis in cerebral infarction (TICI) . Patients with TICI≥2b (17 cases) were divided into good recanalization group whereas patients with TICI≤2a (7 cases) were divided into poor recanalization group. Conscious sedation or general anesthesia was performed according to individual situation. We monitored bilateral regional rSO2 and calculated the values of difference: ΔrSO2 is rSO2 of healthy side minus rSO2 of suffering side. The percentage of difference of bilateral rSO2 (%rSO2) is %rSO2=ΔrSO2/health lateral rSO2. Both ΔrSO2 and percentage of rSO2 were monitored and recorded at different time points: before thrombectomy (T1), 5 min (T2), 15 min(T3) and 30 min (T4) after thrombectomy. Meanwhile, TICI would be evaluated via digital subtraction angiography with intervention by physician. The correlation between ΔrSO2 and TICI was calculated using pearson′s correlation analysis and receiver operating characteristic curve (ROC). The correlation between %rSO2 and TICI was calculated with same method. Results Twenty four patients was enrolled in this study, 17 patients obtained good cerebral blood flow reperfusion with TICI≥2b (good recanalization group) while 7 patients with poor recanalization(TICI≤2a, poor recanalization group). ΔrSO2 and %rSO2 of patients in good recanalization group were decreased significantly after thrombectomy (T2, T3, T4) compared with the values of T1 (P 0.05) at the same time points (T2, T3, T4). Compared with the values of good recanalization group, ΔrSO2 and %rSO2 were significantly higher at T2, T3, T4 time points than T1 time point (P<0.05). The correlation between ΔrSO2 and TICI was also negative correlation, r=-0.78(P=0.00). Similarly, the correlation between %rSO2 and TICI was also negative correlation, r=-0.79(P=0.00). The area under the receiver operating characteristic curve (AUC) of ΔrSO2 and %rSO2 were 0.987 (95%CI 0.973-1.000) and 0.988 (95%CI 0.976-1.000) respectively. The cut off values were 7% and 10% respectively. The values of sensitivity and specificity of ΔrSO2 were 0.933 and 0.988 respectively. The sensitivity and specificity of %rSO2 were 0.933 and 0.996 respectively. Conclusions The changes of ΔrSO2 and %rSO2 reflect cerebral perfusion and have potential clinical values in assessing cerebral perfusion variation in patients with AIS after EVT. Key words: Regional cerebral oxygen saturation; Acute ischemic stroke; Cerebral perfusion; Cerebral metabolism; Near infrared spectroscopy

Application of regional cerebral oxygen saturation monitoring in predicting postoperative delirium in elderly patients

Objective To evaluate the application of regional cerebral oxygen saturation (rSO2) in predicting postoperative delirium (POD) in elderly patients. Methods A total of 140 elderly patients were enrolled in this study. The value of rSO2, mean arterial pressure (MAP), heart rate, pulse oxygen saturation (SpO2) and end-tidal carbon dioxide partial pressure (PETCO2) were monitored at the time of room entry (t0), double-lung ventilation during anesthesia induction (t1), double-lung ventilation during lateral position (t2), single-lung ventilation during lateral position (t3), and extubation after surgery (t4). Meanwhile, the baseline of rSO2, minimum rSO2 (rSO2min), mean rSO2 (rSO2mean) and maximum percentage drop in rSO2 (rSO2%max) were recorded. The patients were divided into a POD group (n=24) and a non-POD group (n=116), according to the definition of POD. The independent risk factors of POD were determined using multivariate Logistic regression, and receiver operating characteristic curve(ROC) analysis was performed to assess the accuracy of rSO2 in predicting POD. Results POD was present in 24 patients among 140 elderly patients (17.1%). At t3 point, the levels of rSO2 were significantly decreased in the POD group compared with the non-POD group (P 0.05). In the POD group, its age and rSO2%max were significantly higher than that in the non-POD group, while its rSO2min and rSO2mean were significantly lower than that in the non-POD group (P<0.05). Logistic regression analysis showed that, age and rSO2%max were the independent risk factors for POD. ROC curve showed that the area under receiver operating characteristic curve (AUC) of rSO2%max was 0.893 (95%CI 0.829-0.939) at a cutoff value of 15.59%. The specificity and sensitivity of rSO2%max in predicting POD were 79.31% and 91.67%, respectively. Conclusions rSO2%max is the independent risk factor for POD in elderly patients after surgery, and rSO2%max>15.59% is considered a potential predictor of POD. Key words: Regional cerebral oxygen saturation; Delirium; Elderly patients; Predictor

Prognostic factors for permanent neurological dysfunction after total aortic arch replacement with regional cerebral oxygen saturation monitoring.

ObjectiveTo explore the prognostic factors for permanent neurological dysfunction (PND) after total aortic arch replacement with regional cerebral oxygen saturation (rSO2) monitoring.MethodsThis retrospective study enrolled 98 type A aortic dissection aneurysm patients who underwent emergency total aortic arch replacement combined with deep hypothermic circulatory arrest and right axillary artery selective antegrade cerebral perfusion (SACP). Data such as age, gender, body mass index, preoperative coexisting disease, laboratory test results, intraoperative critical operation duration, and intraoperative rSO2 were collected, and the neurological prognoses in the hospital were recorded and grouped by severity. Multiple logistic regression analysis was performed on the statistically significant differences between the groups to screen the predictors of postoperative neurological complications in these patients.ResultsForty‐two patients had postoperative neurological complications, among which there were 29 cases (29.6%) of transient neurological dysfunction, and 13 cases (13.3%) of PND. Multiple logistic regression results showed that advanced age, preoperative low platelet count, prolonged hemostasis time and lowest relative rSO2 to baseline (ΔrSO2min) in each time period were risk factors for postoperative PND. The ROC curve measurement showed that the optimal cut‐off value of ΔrSO2min was 79.7%, and the area under the curve was 0.708 (95% confidence interval = 0.557–0.858), p = 0.016; the optimal cut‐off value of ΔrSO2min in SACP was 81.6%, and the area under the curve was 0.720 (95% confidence interval = 0.570–0.870), p = 0.011; the optimal cut‐off value of ΔrSO2min in cardiopulmonary bypass (CPB) was 80.8%, and the area under the curve was 0.697 (95% confidence interval = 0.554–0.840), p = 0.023.ConclusionIntraoperative ΔrSO2min that is lower than the basal level of about 80%, advanced age, preoperative low platelet count, and prolonged hemostasis time are predictors of PND after total aortic arch replacement.

Abstract 209: The Triple CPR 16 study: Does rhythm truly needed to be checked every 2 minutes in Cardiopulmonary Arrest Patients?

Purpose: Current guidelines recommend rhythm checks every 2 minutes during cardiopulmonary resuscitation (CPR), but evidence for this recommendation is insufficient. Recent reports identified regional cerebral oxygen saturation (rSO 2 ) monitoring as useful in detecting return of spontaneous resuscitation (ROSC) and that coronary and cerebral perfusion decreases with the 2-minute rhythm check. On the basis of our previous study, we began the TripleCPR 16 study, which omits 2-minute rhythm checks because stopping chest compression to check rhythm may increase cerebral damage and decrease the ROSC. Methods: The multicenter, prospective TripleCPR 16 study began in January 2017. The inclusion criterion is a cardiopulmonary arrest patient aged ≥16 years with a non-shockable rhythm on hospital arrival. Subjects are divided into 3 groups based on their mean cerebral rSO 2 value in the first minute of arrival: ≥50%, &lt;50% to 40%, and &lt;40%. Continuous mechanical chest compression is performed on all subjects for 16 minutes or until their rSO 2 value exceeds the initial value by 10%, 20%, or 35%, respectively. We are comparing the TripleCPR 16 study results with our previous hospital data obtained from 90 patients who underwent every 2-minute rhythm checks and mechanical chest compression. Result: Currently, 162 patients are registered. Rates of ROSC were 32.1% for these patients and 38.9% for the previous 90 patients (p=0.33). There were no severe adverse events. Subanalysis of the data of Osaka University Hospital alone showed no significant increase of rSO 2 value in the 24 patients with non-sonographic cardiac activity and 21 patients with Stanford type A aortic dissection diagnosed by CT scan, and only one patient in each group achieved ROSC. When excluding the patients with Stanford type A aortic dissection, rates of ROSC were 49.4% for the patients in this study and 39.3% for the previous 90 patients (p=0.21). Conclusion: The TripleCPR 16 study is ongoing without severe adverse events. In the patients with non-sonographic cardiac activity or Stanford type A aortic dissection, rSO 2 values did not increase and it was difficult to achieve ROSC. The 2-minute rhythm check is not essential for chest compression in patients with a non-shockable rhythm.

The TripleCPR 16 study: Does rhythm truly needed to be checked every 2 minutes in cardiopulmonary arrest patients?

Purpose: Current guidelines recommend a rhythm check every 2-minutes during cardiopulmonary resuscitation (CPR), but evidence for this recommendation is insufficient. Recent reports identified regional cerebral oxygen saturation (rSO2) monitoring as useful in detecting return of spontaneous resuscitation (ROSC) and that coronary and cerebral perfusion decrease with the 2-minute rhythm check. On the basis of our previous study, we began the TripleCPR 16 study, which omits the 2-minute rhythm check because stopping chest compression to check rhythm may increase brain cell damage and decrease the rate of ROSC.