
==== Front
JA Clin Rep
JA Clin Rep
JA Clinical Reports
2363-9024
Springer Berlin Heidelberg Berlin/Heidelberg

742
10.1186/s40981-024-00742-z
Case Report
Usefulness of bilateral cerebral regional oxygen saturation measurements in determining selective cerebral perfusion flow rate in a pediatric patient with aortic arch stenosis: a case report
http://orcid.org/0000-0002-6040-4926
Saito Junichi saitoj@hirosaki-u.ac.jp

Ichikawa Shino
Kudo Reiko
Saito Kurumi
Kiyokawa Masayo
Kushikata Tetsuya
https://ror.org/02syg0q74 grid.257016.7 0000 0001 0673 6172 Department of Anesthesiology, Hirosaki University Graduate School of Medicine, 5 Zaifu-Cho, Hirosaki, Aomori 036-8562 Japan
17 9 2024
17 9 2024
12 2024
10 5729 7 2024
24 8 2024
10 9 2024
© The Author(s) 2024
2024
https://creativecommons.org/licenses/by/4.0/ Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.
Background

We report a pediatric case where bilateral regional oxygen saturation (rSO2) measurements were useful in determining the selective cerebral perfusion (SCP) flow rate.

Case presentation

A 9-year-old Japanese boy, 128 cm tall and weighing 25.6 kg, was scheduled for aortic arch reconstruction due to a 90–100 mmHg pressure gradient. Pediatric-sized oximetry sensors were attached to the bilateral forehead area. The rSO2 levels were 70–80% on the right and 80–90% on the left during cardiopulmonary bypass. Immediately following deep hypothermic circulatory arrest with the body temperature cooled to 25 °C, SCP was initiated from the right brachiocephalic artery at 10 mL/kg/min. As the rSO2 decreased steeply to 43–45% on the right and to 32–38% on the left, the SCP flow was increased to 15 mL/kg/min. The right rSO2 increased promptly to 50–60%, but the left rSO2 remained at 30–40%. After the SCP flow was increased to 20 mL/kg/min, bilateral rSO2 levels of 50–60% were obtained, and the SCP flow rate was maintained. The patient was transferred to the ICU postoperatively and extubated on the second postoperative day with no neurological abnormalities.

Conclusions

Bilateral rSO2 measurements are essential even for a pediatric patient undergoing SCP, despite the limited forehead area.

Keywords

Regional oxygen saturation
Selective cerebral perfusion
Aortic arch stenosis
issue-copyright-statement© The Japanese Society of Anesthesiologists 2024
==== Body
pmcBackground

In pediatric cardiac surgery, the selective cerebral perfusion (SCP) flow rate during circulatory arrest lacks an absolute index, leading to substantial variation in the literature [1]. In both pediatric and adult patients undergoing SCP, it is crucial to ensure a sufficient supply of oxygen to the brain, with various monitoring methods, including regional oxygen saturation (rSO2), playing a pivotal role. However, in pediatric patients, rSO2 is often measured by applying only one sheet due to the limited area of the frontal region. We herein report a case in which bilateral cerebral rSO2 measurements were useful in determining SCP flow rate.

Written informed consent was obtained from the patient’s parent for publication of this case report and accompanying images.

Case presentation

A 9-year-old Japanese boy, 128 cm tall and weighing 25.6 kg, was scheduled to undergo ascending aorta replacement and aortic arch reconstruction under general anesthesia. He had been diagnosed with interrupted aortic arch type A and ventricular septal defect at birth, and at 18 days of age had undergone aortoplasty and ventricular septal defect closure. Postoperatively, he was found to have aortic arch stenosis and was followed up in our pediatric department. Nine months prior to surgery, transthoracic echocardiography revealed progressive aortic arch stenosis with a maximum pressure gradient of 90–100 mmHg. Preoperative left ventricular angiography and aortic arch angiography indicated pressures of 170/80 mmHg in the left ventricle, 160/70 mmHg in the ascending aorta, and 80/55 mmHg in the descending aorta (Fig. 1). Physical examination revealed a pressure gradient of 30 mmHg between the upper (113/68 [86] mmHg) and lower (84/53 [67] mmHg) extremities.Fig. 1 Preoperative images of aortic arch stenosis. Intracardiac and aortic pressure was measured by left ventricular and aortic arch angiography 9 months prior to surgery. Aortic arch stenosis with a pressure gradient about 80 mmHg was found. LV left ventricular, Ao aorta, △ pressure gradient

An oral dose of 8 mg midazolam was administered as an anesthetic premedication 1 h before the surgery. In addition to the standard American Society of Anesthesiology monitoring, invasive arterial pressure was monitored in the left radial artery, and central venous pressure was assessed via the right internal jugular vein. A bispectral index sensor and pediatric-sized oximetry sensors were placed on the patient’s forehead. A regional oxygen saturation probe (INVOS 5100C™, Medtronic, Minneapolis, MN, USA) was attached to monitor the cerebral rSO2 values on both sides. Anesthesia was induced and maintained using remimazolam, midazolam, ketamine, and fentanyl. Following the administration of rocuronium bromide, tracheal intubation was performed without any complications. A blood pressure difference of 40 to 50 mmHg was noted between the left radial artery (130/60 mmHg) and the left dorsal artery (90/55 mmHg). After the induction of anesthesia, the baseline bilateral rSO2 values were similar, around 70% (Fig. 2). Once cardiopulmonary bypass (CPB) was established, the body temperature was cooled to 25 °C. The rSO2 during CPB was 70–80% on the right side and 80–90% on the left. Antegrade SCP (10 mL/kg/min) via the brachiocephalic artery was initiated immediately after deep hypothermic circulatory arrest (DHCA). As the rSO2 dropped sharply to 43–45% on the right and 32–38% on the left, the SCP flow was increased to 15 mL/kg/min. The right rSO2 increased promptly to 50–60%, but the left rSO2 remained at 30–40%. After the SCP flow was increased to 20 mL/kg/min, bilateral rSO2 reached levels of 50–60%, and the SCP flow rate was maintained. Following the ascending aorta replacement and aortic arch reconstruction, the patient was weaned from CPB. The pressure gradient between the left radial and dorsal arteries decreased to 15–20 mmHg at the conclusion of surgery. The patient was admitted to the ICU postoperatively and extubated on the second postoperative day with no neurological abnormalities. The intraoperative data were as follows: duration of DHCA 50 min, duration of CPB 2 h 59 min, duration of surgery 5 h 23 min, duration of anesthesia 6 h 43 min.Fig. 2 Changes in bilateral cerebral regional oxygen saturation (rSO2) and mean arterial pressure. Cerebral bilateral rSO2 values changed as the selective cerebral perfusion flow rate increased during deep hypothermic circulatory arrest

Discussion

Bilateral cerebral rSO2 measurements in a patient who had undergone aortic arch reconstruction were useful in determining the SCP flow rate during DHCA. Bilateral cerebral rSO2 measurements are necessary because the left side of the brain may exhibit lower rSO2 compared to the right side, presumably due to blood flow to the left side during SCP from the brachiocephalic artery occurring via the circle of Willis [2]. Moreover, various anatomic variations and obstructions to left-sided venous drainage may affect the blood flow to the left side of the brain [3]. As mentioned above, a prospective study demonstrated that out of 19 neonatal patients who had undergone Norwood surgery, 9 exhibited sustained differences in rSO2 values exceeding 10%, with the left-side values being lower than the right. In some cases, rSO2 differences were as large as 30% [3]. Hence, without monitoring the left side of the brain, undetected desaturation in the left cerebral hemisphere could occur.

In the present case, cerebral rSO2 values rose in conjunction with the escalation of the SCP flow rate. This rate varies widely in the literature, and the optimal flow rate for effective brain protection during development remains unclear. Although the SCP flow rate was defined as 50 mL/kg/min in the initial description of SCP with the DHCA technique [4], the flow rates varied widely, ranging from 20 to 94 mL/kg/min [1]. To overcome the uncertainties around the SCP flow rate, a suggested approach involved adjusting the flow rate to maintain cerebral rSO2 and Doppler flow velocity to within 10% of the baseline values recorded during full-flow CPB [2]. However, thresholds of rSO2 associated with central nervous system injury in pediatric cardiac surgery are under investigation and also there was no clear evidence for avoiding the injury during SCP. Some basic and clinical studies revealed that thresholds of near-infrared spectroscopy for cerebral injury were oxygen saturations in the range of 33 to 55% during perioperative period [5–8]. In a piglet model to determine thresholds for neurologic injury, brain tissue lactate accumulation began when cerebral rSO2 values decreased to less than 45% [7]. A clinical study also revealed that the development of new or worsened ischemia on postoperative magnetic resonance imaging following the Norwood procedure was associated prolonged low postoperative cerebral rSO2 values (rSO2 < 45% for > 180 min) [9]. These results suggest that cerebral rSO2 values at least 45% should be maintained during SCP. On the contrary, with 14 out of 34 patients exhibiting cerebral rSO2 values of 95% [2], there is a potential risk of cerebral hyperperfusion, and brain injury can occur at high cerebral rSO2 levels if the guidance for SCP flow relies solely on rSO2 measurements. Further studies are needed to elucidate the targeted cerebral rSO2 levels during SCP in pediatric patients.

In addition to the evaluation of local tissue ischemia, measurement of rSO2 in patients with congenital heart disease has some advantages. The baseline values of rSO2 during the induction of anesthesia are clinically important to assess the global cardiopulmonary function of congenital heart disease patients. Previous studies showed that preoperative rSO2 values in awake state could be used to predict poor outcomes in patients undergoing congenital heart surgery [10]. Additionally, we have previously reported that baseline rSO2 values after induction of anesthesia were associated with several adverse postoperative outcomes [11] and Modestini and colleagues supported our findings; lower baseline rSO2 values were associated with a longer ICU and hospital stay, as well as with a longer duration of mechanical ventilation [12]. As shown previously in adult patients undergoing cardiac surgery, low preoperative rSO2 values were associated not only with neurologic adverse outcome but also with increased mortality rates [13]. These results suggested that the brain might be an “index organ” reflecting the severity of cardiopulmonary compromise in patients with cardiac disease [14].

This case showed that bilateral cerebral rSO2 measurements in a pediatric patient undergoing aortic arch reconstruction were useful in establishing the SCP flow rate during DHCA. Although the limited frontal area of a pediatric patient makes bilateral rSO2 measurements difficult, such measurements are indispensable, especially in the context of a pediatric patient undergoing SCP.

Abbreviations

rSO2 Regional oxygen saturation

SCP Selective cerebral perfusion

CPB Cardiopulmonary bypass

DHCA Deep hypothermic circulatory arrest

Acknowledgements

None.

Authors’ contributions

JS: managed this case in the operation room and drafted the manuscript. SI, RK, KS: managed this case in the intensive care unit and helped to draft the manuscript. MK: managed this case in the operation room and revised the manuscript. TK: managed this case in the operation room and extensively revised the manuscript.

Funding

No.

Availability of data and materials

No data available.

Declarations

Ethics approval and consent to participate

NA.

Consent for publication

Written informed consent was obtained from the patient’s parent for publication of this case report and accompanying images.

Competing interests

None.

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
==== Refs
References

1. Fraser CD, Jr., Andropoulos DB. Principles of antegrade cerebral perfusion during arch reconstruction in newborns/infants. Semin Thorac Cardiovasc Surg Pediatr Card Surg Annu. 2008:61–8.
2. Andropoulos DB Stayer SA McKenzie ED Fraser CD Jr Novel cerebral physiologic monitoring to guide low-flow cerebral perfusion during neonatal aortic arch reconstruction J Thorac Cardiovasc Surg 2003 125 3 491 499 10.1067/mtc.2003.159 12658190
Andropoulos DB, Stayer SA, McKenzie ED, Fraser CD Jr. Novel cerebral physiologic monitoring to guide low-flow cerebral perfusion during neonatal aortic arch reconstruction. J Thorac Cardiovasc Surg. 2003;125(3):491–9.12658190
3. Andropoulos DB Diaz LK Fraser CD Jr. McKenzie ED Stayer SA Is bilateral monitoring of cerebral oxygen saturation necessary during neonatal aortic arch reconstruction? Anesth Analg. 2004 98 5 1267 72 10.1213/01.ANE.0000111114.48702.59 15105198
Andropoulos DB, Diaz LK, Fraser CD Jr., McKenzie ED, Stayer SA. Is bilateral monitoring of cerebral oxygen saturation necessary during neonatal aortic arch reconstruction? Anesth Analg. 2004;98(5):1267–72 table of contents.15105198
4. Asou T Kado H Imoto Y Shiokawa Y Tominaga R Kawachi Y Selective cerebral perfusion technique during aortic arch repair in neonates Ann Thorac Surg 1996 61 5 1546 1548 10.1016/0003-4975(96)80002-S 8633985
Asou T, Kado H, Imoto Y, Shiokawa Y, Tominaga R, Kawachi Y, et al. Selective cerebral perfusion technique during aortic arch repair in neonates. Ann Thorac Surg. 1996;61(5):1546–8.8633985
5. Dent CL Spaeth JP Jones BV Schwartz SM Glauser TA Hallinan B Brain magnetic resonance imaging abnormalities after the Norwood procedure using regional cerebral perfusion J Thorac Cardiovasc Surg 2005 130 6 1523 1530 10.1016/j.jtcvs.2005.07.051 16307993
Dent CL, Spaeth JP, Jones BV, Schwartz SM, Glauser TA, Hallinan B, et al. Brain magnetic resonance imaging abnormalities after the Norwood procedure using regional cerebral perfusion. J Thorac Cardiovasc Surg. 2005;130(6):1523–30.16307993
6. Hagino I Anttila V Zurakowski D Duebener LF Lidov HG Jonas RA Tissue oxygenation index is a useful monitor of histologic and neurologic outcome after cardiopulmonary bypass in piglets J Thorac Cardiovasc Surg 2005 130 2 384 392 10.1016/j.jtcvs.2005.02.058 16077403
Hagino I, Anttila V, Zurakowski D, Duebener LF, Lidov HG, Jonas RA. Tissue oxygenation index is a useful monitor of histologic and neurologic outcome after cardiopulmonary bypass in piglets. J Thorac Cardiovasc Surg. 2005;130(2):384–92.16077403
7. Kurth CD Levy WJ McCann J Near-infrared spectroscopy cerebral oxygen saturation thresholds for hypoxia-ischemia in piglets J Cereb Blood Flow Metab 2002 22 3 335 341 10.1097/00004647-200203000-00011 11891439
Kurth CD, Levy WJ, McCann J. Near-infrared spectroscopy cerebral oxygen saturation thresholds for hypoxia-ischemia in piglets. J Cereb Blood Flow Metab. 2002;22(3):335–41.11891439
8. Kurth CD McCann JC Wu J Miles L Loepke AW Cerebral oxygen saturation-time threshold for hypoxic-ischemic injury in piglets Anesth Analg 2009 108 4 1268 1277 10.1213/ane.0b013e318196ac8e 19299799
Kurth CD, McCann JC, Wu J, Miles L, Loepke AW. Cerebral oxygen saturation-time threshold for hypoxic-ischemic injury in piglets. Anesth Analg. 2009;108(4):1268–77.19299799
9. Hoffman GM Brosig CL Mussatto KA Tweddell JS Ghanayem NS Perioperative cerebral oxygen saturation in neonates with hypoplastic left heart syndrome and childhood neurodevelopmental outcome J Thorac Cardiovasc Surg 2013 146 5 1153 1164 10.1016/j.jtcvs.2012.12.060 23317941
Hoffman GM, Brosig CL, Mussatto KA, Tweddell JS, Ghanayem NS. Perioperative cerebral oxygen saturation in neonates with hypoplastic left heart syndrome and childhood neurodevelopmental outcome. J Thorac Cardiovasc Surg. 2013;146(5):1153–64.23317941
10. Fenton KN Freeman K Glogowski K Fogg S Duncan KF The significance of baseline cerebral oxygen saturation in children undergoing congenital heart surgery Am J Surg 2005 190 2 260 263 10.1016/j.amjsurg.2005.05.023 16023442
Fenton KN, Freeman K, Glogowski K, Fogg S, Duncan KF. The significance of baseline cerebral oxygen saturation in children undergoing congenital heart surgery. Am J Surg. 2005;190(2):260–3.16023442
11. Saito J Takekawa D Kawaguchi J Suganuma T Konno M Noguchi S Preoperative cerebral and renal oxygen saturation and clinical outcomes in pediatric patients with congenital heart disease J Clin Monit Comput 2019 33 6 1015 1022 10.1007/s10877-019-00260-9 30666542
Saito J, Takekawa D, Kawaguchi J, Suganuma T, Konno M, Noguchi S, et al. Preoperative cerebral and renal oxygen saturation and clinical outcomes in pediatric patients with congenital heart disease. J Clin Monit Comput. 2019;33(6):1015–22.30666542
12. Modestini M Hoffmann L Niezen C Armocida B Vos JJ Scheeren TWL Cerebral oxygenation during pediatric congenital cardiac surgery and its association with outcome: a retrospective observational study Can J Anaesth 2020 67 9 1170 1181 10.1007/s12630-020-01733-1 32557197
Modestini M, Hoffmann L, Niezen C, Armocida B, Vos JJ, Scheeren TWL. Cerebral oxygenation during pediatric congenital cardiac surgery and its association with outcome: a retrospective observational study. Can J Anaesth. 2020;67(9):1170–81.32557197
13. Heringlake M Garbers C Kabler JH Anderson I Heinze H Schon J Preoperative cerebral oxygen saturation and clinical outcomes in cardiac surgery Anesthesiology 2011 114 1 58 69 10.1097/ALN.0b013e3181fef34e 21178669
Heringlake M, Garbers C, Kabler JH, Anderson I, Heinze H, Schon J, et al. Preoperative cerebral oxygen saturation and clinical outcomes in cardiac surgery. Anesthesiology. 2011;114(1):58–69.21178669
14. Murkin JM Cerebral oximetry: monitoring the brain as the index organ Anesthesiology 2011 114 1 12 13 10.1097/ALN.0b013e3181fef5d2 21178667
Murkin JM. Cerebral oximetry: monitoring the brain as the index organ. Anesthesiology. 2011;114(1):12–3.21178667
