Surgery and anesthesia induce inflammatory changes in the central nervous system, which ultimately lead to neuronal damage concomitant with an increase in the level of neurodegeneration markers. Despite some experimental data showing prolonged activation of the immune system post-surgery, no study has determined the extent of long-term elevation of neurodegeneration markers. The purpose of this study was to investigate the serum levels of tau protein, ubiquitin carboxyl-terminal hydrolase L1 (UCH-L1), neurofilament light (NF-L), and glial fibrillary acidic protein (GFAP) after elective cardiac surgery with the implementation of cardiopulmonary bypass (CPB). The serum levels of these markers from 30 patients were compared longitudinally to the baseline (pre-surgery or t 0 ), at 24 hours (t +24 ), at 7 days (t +7d ), and at 3 months (t +3m ). The secondary outcome was the production of macrophage-colony stimulating factor (M-CSF) and tumor necrosis factor-α (TNF-α) in vitro by isolated monocytes in response to lipopolysaccharide (LPS) as the measure of immune system activation. The tertiary outcome was the serum level of C-reactive protein (CRP), serum amyloid P (SAP), and α-2-macroglobulin (A2M). Serum levels of tau protein increased 24 hours after surgery (p = 0.0015) and remained elevated at 7 days ( p = 0.0017) and three months ( p = 0.036). Serum levels of UCH-L1 peaked at 24 hours ( p = 0.00055) and normalized at 3 months. In vitro secretion of M-CSF by LPS-stimulated peripheral monocytes, but not TNFα, correlated highly ( r = 0.58; p = 0.04) with persistent elevation of serum tau levels at 3 months. The serum CRP and SAP increases correlated with tau post-CPB levels significantly at 3 months. We demonstrated that elevation of serum tau levels at 24 hours, 7 days, and 3 months after heart surgery is concomitant with some traits of inflammation after CPB. The elevation of tau several weeks into recovery is significantly longer than expected.

Currently in the caring professions, the human condition of facing uncertainty and danger is often overlooked in the quest for measurable outcomes that prove efficiency, taking agency out of the hands of the individuals being cared for. Traits that make an ‘ideal’ practitioner include compassion, advocacy skills, and the ability to engage with people in vulnerable situations, and to establish trusting, respectful relationships. Within a system of models, quotas, and specialties, these traits are easily hindered within health care and humanitarianism. The critical examination in this article in no way rejects the valuable elements in the fields of humanitarianism and health care. Rather, it discusses how care can be re-introduced. Uncertainty and danger are part of the human experience, and caring interventions need to take that into account. This article highlights the benefits of a collaborative relationship between the person in crisis and the practitioner, instead of a paternalistic relationship in which the practitioner is viewed as the ‘expert.’ With a caring perspective, the individual who is experiencing the crisis will retain ownership of and responsibility for their life, and not rely solely on external sources of wellbeing and comfort.

No abstract