Data from: Surgery impairs glymphatic activity and cognitive function in aged mice

Delirium is a common complication in elderly surgical patients and is
associated with an increased risk of dementia. Although advanced age is a
major risk factor, the mechanisms underlying postoperative delirium remain
poorly understood. The glymphatic system, a brain-wide network of
perivascular pathways, facilitates cerebrospinal fluid (CSF) flow and
supports the clearance of metabolic waste. Impairments in glymphatic
function have been observed in aging brains and various neurodegenerative
conditions. Using in vivo two-photon imaging, we examined the effects of
surgery (laparotomy) on glymphatic function in adult (6 months) and aged
(18 months) mice 24 h post-surgery. In adult mice, CSF tracer entry into
the brain parenchyma along periarteriolar spaces occurred rapidly
following intracisternal tracer injection, with no significant differences
between sham and surgery groups. In contrast, aged mice exhibited delayed
tracer influx, with further impairments observed in the surgery group
compared to sham controls. This glymphatic dysfunction correlated with
poorer T-maze performance in aged mice. These findings suggest that
surgery exacerbates glymphatic impairment in aging brains, potentially
hindering brain waste clearance and contributing to postoperative
delirium.