General anesthesia

…of the unconscious brain under general anesthesia, hosted by the Wu Tsai Neurosciences Institute.

…AD patients are more susceptible to anesthesia-induced postoperative cognitive dysfunction, which is in line with the well-known fact that general anesthesia is more detrimental in the two extreme age groups, neonates/infants and the elderly. Alfaxalone (ALX) is the synthetic analog of allopregnanolone. It is currently in use only in veterinary practice as a fast-acting anesthetic with a high thera

General anesthesia (GA) is an unconscious state produced by anesthetic drugs, which act on neurons to cause overall suppression of neuronal activity in the brain. Recent studies have revealed that GA also substantially enhances the dynamics of microglia, the primary brain immune cells, with increased process motility and territory surveillance. However, whether microglia are actively involved in GAmodulation remains unknown. Here, we report a previously unrecognized role for microglia engaging in multiple GA processes. We found that microglial ablation reduced the sensitivity of mice to anesth

…to 80% of patients after surgery under general anesthesia (GA). The systemic and mechanistic relationship between preoperative anxiety (POA) and POD is largely unknown. A preoperative anxious phenotype and the identification of sleep impairments due to it hold the strong potential to establish predictive parameters for POD. These discoveries may further elucidate the neuronal mechanisms underlying POA and POD. 37 C57BL/6N male mice (12-weeks-old)

Understanding the circuit mechanisms underlying the loss of consciousness during general anesthesia is a long-standing question. Activity within cortex drives conscious perception and, hence, the loss of consciousness is thought to result from the disconnection of cortex from subcortex. Here, we identify a change in the correlation structure of neuronal activity during general anesthesia, specific to the primary population of cortical output neurons. We demonstrate that this increased correlation reduces the information output from cortex, suggesting a mechanism for the loss of consciousness.

General anesthesia is a drug-induced, reversible condition comprised of five behavioral states: unconsciousness, amnesia (loss of memory), antinociception (loss of pain sensation), akinesia (immobility), and hemodynamic stability with control of the stress response. Our work shows that a primary mechanism through which anesthetics create these altered states of arousal is by initiating and maintaining highly structured oscillations. These oscillations impair communication among brain regions. We illustrate this effect by presenting findings from our human studies of general anesthesia using hi