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

Influence of blood loss on cerebral oxygen saturation in paediatric patients undergoing surgery for scoliosis correction: A retrospective observational study

AIM

Surgery for congenital scoliosis correction in children is often associated with considerable blood loss. Decrease in regional oxygen saturation (rScO2) can reflect insufficient cerebral perfusion and predict neurological complications. This retrospective observational study explored the relationship between blood loss during this surgery and a decrease in rScO2 in children.

METHODS

The following clinical data of children aged 3-14 years who underwent elective posterior scoliosis correction between March 2019 and July 2021 were collected: age, sex, height, weight, baseline rScO2, basal mean invasive arterial pressure (MAP), preoperative Cobb angle, number of surgical segments, preoperative and postoperative haemoglobin level, percentage of lowest rScO2 below the baseline value that lasted 3 min or more during the operation (decline of rScO2 from baseline, D-rScO2%), intraoperative average invasive MAP, end-tidal carbon dioxide pressure, fluid infusion rate of crystalloids and colloids, operation time, and percentage of total blood loss/patient's blood volume (TBL/PBV).

RESULTS

A total of 105 children were included in the study. Massive haemorrhage (TBL/PBV ≥50%) was reported in 53.3% of patients, who had significantly higher D-rScO2 (%) (t = -5.264, P < 0.001) than those who had non-massive haemorrhage (TBL/PBV <50%). Multiple regression analysis revealed that TBL/PBV (β = 0.04, 95% CI: 0.018-0.062, P < 0.05) was significantly associated with D-rScO2%.

CONCLUSIONS

Intraoperative massive blood loss in children significantly increased D-rScO2%. Monitoring should be improved, and timely blood supplementation should be performed to ensure maintenance of the blood and oxygen supply to vital organs, improve the safety of anaesthesia, and avoid neurological complications.

Prevalence of carotid artery stenosis and intra-cranial lesions in patients with aortic arch aneurysm and its association with intraoperative regional cerebral oxygen saturation and postoperative neurological outcomes

Background

Although aortic aneurysm is associated with vascular aging and atherosclerosis, carotid and intracranial vascular disease prevalence in patients with aortic arch aneurysm remains unclear. Similarly, the effect of carotid and intracranial lesions on postoperative outcomes is unknown. This study aimed to investigate the prevalence of carotid artery stenosis and intracranial lesions in patients with aortic arch aneurysm and its association with intraoperative regional cerebral oxygen saturation (rScO2) and postoperative neurological outcomes, including delirium and cerebral infarction.

Methods

This retrospective observational study included 133 patients with true aortic arch aneurysm who underwent preoperative magnetic resonance imaging (MRI). We evaluated the prevalence of carotid and intracranial arterial lesions. Symptomatic cerebral infarction and delirium, defined by the confusion assessment method for the intensive care unit, were evaluated for their association with preoperative cerebrovascular lesions. Additionally, changes in regional saturation of the cerebral tissue at different surgical phases were evaluated for patients with and without cerebrovascular lesions.

Results

Fifteen (11.3%) patients experienced symptomatic cerebral infarction, and 64 (48.1%) had postoperative delirium. Preoperative MRI showed old infarction, microbleeds, significant carotid artery stenosis, and intracranial lesions in 21.1%, 14.3%, 10.5%, and 7.5% of the patients, respectively. White matter hyperintensities with Fazekas scale 2 were observed in 40.6% of the patients, while Fazekas scale 3 were observed in 18.8% of the patients. Preoperative MRI findings and postoperative neurological outcomes were not significantly different. Seventy-six patients underwent rScO2 monitoring intraoperatively. Changes in rScO2 in patients with and without carotid/cerebrovascular lesions were not significantly different. However, rScO2 was significantly lower in patients who developed cerebral infarction.

Conclusions

Significant carotid artery stenosis and intracranial lesions were observed in 10.5% and 7.5% of the patients, respectively. Although preoperative MRI findings and changes in rScO2 or postoperative outcomes showed no significant association, patients with postoperative cerebral infarction showed significantly lower rScO2 intraoperatively.

Development of a nomogram to predict negative postoperative behavioral changes based on a prospective cohort

BACKGROUND

It is believed that negative postoperative behavioral changes (NPOBC) is associated with negative perioperative outcomes in children. The importance of development of a predictive model of NPOBC was noted. This study aims to identify potential risk factors develop a nomogram to predict NPOBC on postoperative day 3 based on a prospective cohort.

METHODS

A prospective observational study was conducted on children(American Society of Anesthesiologists I ~ III) aged 2 ~ 12 years who underwent selective surgery under general anesthesia between September 2022 and February 2023. The patient's clinical data were analyzed. The method of measuring NPOBC is with the The Posthospital Behaviour Questionnaire (PHBQ), and all of children remained hospitalized at the time of assessment. The enrolled patients were categorized into the NPOBC group and the non-NPOBC group according to if children developed NPOBC on postoperative day 3. Univariate and multivariate logistic regression analyses were performed to identify independent risk factors and develop the nomogram to predict NPOBC. Internal validation was performed using the parametric bootstrapping method.

RESULTS

One hundred ninety-two patients were enrolled in the study, 44.8% (86/192 patients) of children developed NPOBC on postoperative day 3. Univariate and multivariate logistic regression analysis demonstrated that the Pediatric Anesthesia Behavior (PAB) score (OR: 1.23, 95%CI: 1.14-1.33), cerebral desaturation (OR: 1.16, 95%CI: 1.02-1.32), and postoperative pain score (OR: 1.07, 95%CI: 1.02-1.13) were independent predictors for NPOBC on postoperative day 3 (P < 0.05). They were used to develop the prediction model. The calibration curve demonstrated satisfied discrimination and calibration of the prediction model. The model presented with good discriminative ability (area under the receiver operating characteristic curve: 0.762 [95%CI: 0.691-0.833]). The decision curve analysis also revealed the great clinical utility of the nomogram.

CONCLUSION

Based on our prospective observational study, pre-anesthesia patients with higher PAB scores, presence of cerebral desaturation, and higher postoperative pain score were more likely to develop NPOBC on postoperative day 3. We established and validated a nomogram for predicting NPOBC, which could help assess patients individually, identify high-risk groups of NPOBC and improve patient prognosis.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, ChiCTR-2,200,059,776. Registered 11 May 2022.

Effects of Different Hemoglobin Levels on Near-Infrared Spectroscopy-Derived Cerebral Oxygen Saturation in Elderly Patients Undergoing Noncardiac Surgery

Background

Near-infrared spectroscopy (NIRS) is a commonly used technique to evaluate tissue oxygenation and prevent harmful cerebral desaturation in the perioperative setting. The aims of the present study were to assess whether surgery-related anemia can be detected via NIRS of cerebral oxygen saturation and to investigate the effects of different perioperative transfusion strategies on cerebral oxygenation, potentially affecting transfusion decision-making.

Study Design and Methods

Data from the ongoing multicenter LIBERAL-Trial (liberal transfusion strategy to prevent mortality and anemia-associated ischemic events in elderly noncardiac surgical patients, LIBERAL) were used. In this single-center sub-study, regional cerebral oxygenation saturation (rSO2) was evaluated by NIRS at baseline, pre-, and post-RBC transfusion. The obtained values were correlated with blood gas analysis-measured Hb concentrations.

Results

rSO2 correlated with Hb decline during surgery (r = 0.35, p < 0.0001). Different RBC transfusion strategies impacted rSO2 such that higher Hb values resulted in higher rSO2. Cerebral desaturation occurred at lower Hb values more often.

Discussion

Cerebral oxygenation monitoring using NIRS provides noninvasive rapid and continuous information regarding perioperative alterations in Hb concentration without the utilization of patients' blood for blood sampling. Further investigations are required to demonstrate if cerebral rSO2 may be included in future individualized transfusion decision strategies.

Reduced regional cerebral oxygen saturation increases risk for emergence delirium in pediatric patients

Objectives

To assess whether decreased regional cerebral oxygen saturation (rScO₂) is associated with the emergence delirium (ED) following general anesthesia in the pediatric population.

Methods

A retrospective observational cohort study was conducted on 113 children (ASA I-III) aged 2-14 years who underwent selective surgery under general anesthesia between 2022-01 and 2022-04. Intraoperatively, the rScO₂ was monitored using a cerebral oximeter. The Pediatric Anesthesia Emergence Delirium (PAED) score was used to evaluate the patients for ED.

Results

The incidence of ED was 31%. Low rScO₂ was reported in 41.6% of patients, who had a higher incidence of ED (P < 0.001) than those who did not experience desaturation. Logistic regression analysis revealed that decreased rScO₂ was significantly associated with incident ED events [odds ratio (OR), 10.77; 95% confidence interval, 3.31-35.05]. Children under 3 years of age had a higher incidence of ED after rScO₂ desaturation during anesthesia compared to older children (OR, 14.17 vs. 4.64).

Conclusion

Intraoperative rScO₂ desaturation significantly increased the incidence of ED following general anesthesia. Monitoring should be enhanced to improve the oxygen balance in vital organs to improve the quality and safety of anesthesia.

Perioperative Pediatric Erythrocyte Transfusions: Incorporating Hemoglobin Thresholds and Physiologic Parameters in Decision-making

This article presents current literature and scientific evidence on hemoglobin thresholds and physiologic parameters to guide decisions regarding perioperative erythrocyte transfusions in pediatric patients based on the most up-to-date studies and expert consensus recommendations.

Intraoperative hypotension during surgical treatment for Marfan syndrome scoliosis in children

PURPOSE

To explore the occurrence and risk factors of intraoperative hypotension during children's Marfan syndrome scoliosis surgery and summarize the associated hemodynamic features and handle measures.

METHODS

Twenty-two Marfan syndrome scoliosis patients who underwent spinal surgery at Beijing Children's Hospital were retrospectively reviewed between January 2001 and January 2020. Intraoperative hypotension is defined as the minimum mean arterial pressure ≤ 60 mm Hg. The patients were divided into the hypotension group and the control group. Clinical, radiographic, and operative data were compared between the two groups. The risk factors, hemodynamic features, and handle measures for intraoperative hypotension in Marfan syndrome scoliosis surgery were analyzed and summarized.

RESULTS

Twenty-two patients were included in the study, with a mean age of 11.4 years at initial surgery. The follow-up period ranged from 24 to 152 months. Intraoperative hypotension occurred in 14 cases, with an incidence of 63.6%. The proportion of pulmonary dysfunction in the hypotension group was higher than in the control group (100.0% vs 50.0%, p < 0.05). The spinal flexibility was significantly lower in the hypotension group (28.3% ± 14.2% vs 46.5% ± 11.5%, p < 0.05). Fourteen patients with intraoperative hypotension had decreased intraoperative systolic blood pressure 21.0%-50.0% compared with baseline. One patient had a transient decrease in the muscle strength of the lower limbs. No complications were observed during the follow-up.

CONCLUSION

The incidence of intraoperative hypotension in Marfan syndrome scoliosis children who underwent surgery was 63.6%. The risk factors included preoperative pulmonary dysfunction and poor spinal flexibility. Comprehensive preoperative evaluation and effective hemodynamic handling measures should be undertaken to prevent further complications in children with Marfan syndrome scoliosis.

Cerebral oxygen saturation as outcome predictor after transfemoral transcatheter aortic valve implantation

BACKGROUND

Cerebral oxygen saturation (ScO2) can be measured non-invasively by near-infrared spectroscopy (NIRS) and correlates with cerebral perfusion. We investigated cerebral saturation during transfemoral transcatheter aortic valve implantation (TAVI) and its impact on outcome.

METHODS AND RESULTS

Cerebral oxygenation was measured continuously by NIRS in 173 analgo-sedated patients during transfemoral TAVI (female 47%, mean age 81 years) with self-expanding (39%) and balloon-expanding valves (61%). We investigated the periprocedural dynamics of cerebral oxygenation. Mean ScO2 at baseline without oxygen supply was 60%. During rapid ventricular pacing, ScO2 dropped significantly (before 64% vs. after 55%, p < 0.001). ScO2 at baseline correlated positively with baseline left-ventricular ejection fraction (0.230, p < 0.006) and hemoglobin (0.327, p < 0.001), and inversely with EuroSCORE-II ( - 0.285, p < 0.001) and length of in-hospital stay ( - 0.229, p < 0.01). Patients with ScO2 < 56% despite oxygen supply at baseline had impaired 1 year survival (log-rank test p < 0.01) and prolonged in-hospital stay (p = 0.03). Furthermore, baseline ScO2 was found to be a predictor for 1 year survival independent of age and sex (multivariable adjusted Cox regression, p = 0.020, hazard ratio (HR 0.94, 95% CI 0.90-0.99) and independent of overall perioperative risk estimated by EuroSCORE-II and hemoglobin (p = 0.03, HR 0.95, 95% CI 0.91-0.99).

CONCLUSIONS

Low baseline ScO2 not responding to oxygen supply might act as a surrogate for impaired cardiopulmonary function and is associated with worse 1 year survival and prolonged in-hospital stay after transfemoral TAVI. ScO2 monitoring is an easy to implement diagnostic tool to screen patients at risk with a potential preserved recovery and worse outcome after TAVI.

Association of regional cerebral oxygen saturation and postoperative pulmonary complications in pediatric patients undergoing one-lung ventilation: A propensity score matched analysis of a prospective cohort study

BACKGROUND

Previous studies of the relationship of regional cerebral oxygen saturation (rScO2) and postoperative pulmonary complications (PPCs) in pediatric patients are not well established, and further investigation is warranted. The aim of this prospective study was to determine whether a decrease in intraoperative rScO2 is associated with PPCs in children undergoing thoracoscopic surgery requiring one-lung ventilation (OLV).

METHODS

One hundred and six children of ages 3 months to 8 years who received one-lung ventilation were enrolled in the study. Upon entering the operating room, regional cerebral oxygen saturation was continuously monitored bilaterally by near-infrared spectroscopy. Patients were divided into low rScO2 (L-rScO2) or high rScO2 (H- rScO2) groups according to whether the lowest intraoperative rScO2 value was 15% lower than the baseline value. Outcome is defined as PPCs occurring within 7 days after surgery.

RESULTS

After propensity score matching, 23 pediatric patients with decreased rScO2 and 46 pediatric patients without a decrease in rScO2 were included in this study. According to logistic regression analysis, patients in the H- rScO2 group were less likely to have PPCs than those in the L-rScO2 group (OR = 3.16; 95% CI = 1.05-9.5; P = 0.04). Moreover, intraoperative rScO2 reduction was associated with an increase in the severity of PPCs (OR = 3.90; 95% CI = 1.19-12.80; P = 0.025).

CONCLUSIONS

The decrease in regional cerebral oxygen saturation during surgery increases the likelihood of postoperative pulmonary complications.