Relationship between regional cerebral blood volume and oxygenation and blood pressure during spinal anesthesia in women undergoing cesarean section

Abstract

Maternal rCBV and rCBO decrease significantly during spinal anesthesia for cesarean section. Reductions in rCBV and rCBO may be associated with the severity of hypotension induced by subarachnoid sympathetic block with bupivacaine.

Neurovascular Coupling by Functional Near Infra-Red Spectroscopy and Sport-Related Concussion in Retired Rugby Players: The UK Rugby Health Project

“…The mTBI group had their left caudal PFC (channel 7) as the strongest O 2 Hb signal. This coincides with literature (Oudegeest-Sander et al, 2014;Hirose et al, 2016) as they both measured hemodynamics and reported tHb will be greater at baseline for the control group as mTBI individuals will have overcompensation of HHb from a lack of O 2 Hb, which may be indicative of conditions such as ischemia. From a practical perspective, this is telling of impacts to the prefrontal cortex as channel 6 is over the left MFG.…”

“…tHb had the lowest signal in channel 5 (dorsolateral PFC) for both groups, meaning tHb (Figure 4) is matched for the NVC response, but differences in O 2 Hb and HHb hemodynamics do occur. This is supported in the literature (Hirose et al, 2016;Curtelin et al, 2017;Hocke et al, 2018) as tHb is equated within controls which are a compensatory mechanism from the change between O 2 Hband HHb resulting in a reduction of variability for mTBI individuals. Similar findings have been observed in the standard deviation of O 2 Hb using NIRS in a group of mTBI athletes following acute concussion (Bishop and Neary, 2018).…”

International consensus statement on the management of hypotension with vasopressors during caesarean section under spinal anaesthesia

“…Acute hypotension reduces cerebral perfusion, induces transient brainstem ischaemia and activates the vomiting centre. Transient cerebral hypoxia may occur, as studies using near‐infrared spectroscopy (NIRS) show that hypotension is accompanied by a significant decrease in maternal regional cerebral blood volume, cerebral oxygen saturation and oxygenation . This is consistent with the observation that supplemental oxygen may relieve this nausea .…”

Regional block: who first thought of such an approach?

“…Based on my own experience, I am not very fond of spinal block, but it is still commonly used as an anesthetic technique, particularly in cesarean section. Hirose et al [5] measured the concentration of total hemoglobin and the tissue oxygen index during spinal anesthesia for pregnant women undergoing cesarean section and show that both decrease in proportion to the degree of hypotension caused by bupivacaine administration. The authors attribute this finding to decreases in cerebral blood flow and oxygenation.…”