Cesarean delivery under spinal anesthesia is associated with decreases in cerebral oxygen saturation as assessed by NIRS: an observational study

Abstract

Objectives:

To investigate the effect of spinal anesthesia on cerebral rSO₂ during elective cesarean delivery (CD).

Methods:

Thirty-four women scheduled for elective CD under spinal anesthesia were recruited. In the operating room rSO₂ of the left and right frontal area and right thigh was recorded using three disposable sensors. A combination of 1.8–2.0 ml of 0.75% ropivacaine plus 10 μg of fentanyl were injected intrathecally. Systolic and diastolic blood pressure, heart rate, SpO₂ as well as rSO₂ of the left and right forehead areas and right thigh were recorded before, 5, 10, and 25 to 50 minutes after spinal injection, after uterine incision and placenta delivery, and analyzed with ANOVA repeated measures. The study was approved by the Aretaieio Hospital Institutional Review Board and registered with ClinicalTrials.gov (ID: NCT01669135).

Results:

The rSO₂ left and right frontal area values decreased significantly from baseline (p = 0.0001 and p = 0.0001 respectively), with most remarkable decreases 5 and 10 minutes after spinal injection, from 65 (SD 8.7) % to 56 (SD 9.3) % and 56 (SD 9.5) % (p = 0.0001 and p = 0.0001) for the left and from 63 (SD 7.7) % to 55 (SD 9.3) % and 56 (SD 8.9) % (p = 0,0001 and p = 0.0001) for the right frontal area respectively. The rSO₂ right thigh values increased significantly during the study period (p = 0.0001).

Key limitations:

Contribution of extracranial circulation to the rSO₂, lack of PaCO₂ and cardiac output measurements.

Conclusions:

Women undergoing CD under spinal anesthesia may present decreases in cerebral rSO₂. The clinical impact of these results remains to be determined.

Trial registration: ClinicalTrials.gov identifier: NCT01669135.

Keywords::

• Cerebral oxygen saturation
• Cesarean delivery
• Near-infrared spectroscopy (NIRS)
• Spinal anesthesia

Transparency

Declaration of funding

This study was supported by a grant from ‘Kapodistrias’ Program Code Number 70/4/6596, National and Kapodistrian University of Athens. Funding was from the Athens University to the Chairman of the Department. Role of the sponsor: none.

Declaration of financial/other relationships

A.F., A.P., and A.T. have disclosed that they have no significant relationships with or financial interests in any commercial companies related to this study or article.

CMRO peer reviewers may have received honoraria for their review work. The peer reviewers on this manuscript have disclosed that they have no relevant financial relationships.