Monitoring the incidence of hypotension and hypoxemia as systemic secondary insults in patients with catastrophic brain injury evolving to brain death. A prospective observational pilot study

Purpose Maintenance of systemic homeostasis and prevention of secondary injury are a cornerstone of treatment in neurocritical care to prevent organ dysfunction and adverse clinical outcome. This is a pilot descriptive and hypothesis generating study aiming to measure and characterize the incidence of systemic hypotension and hypoxemia occurring during the intensive care unit (ICU) stay in patients with catastrophic brain injury potentially evolving to brain death. Methods Adult patients admitted to ICU with catastrophic brain injury and Glasgow coma scale ≤5 have been enrolled. Arterial blood pressure and SpO2 were collected minute by minute from a central station connected to patients’ bedside monitors. Results We report on 24 patients recruited prospectively from the University Hospital of Messina, Italy as a part of a larger ongoing multi-centre study. Patient monitoring data ranged from 8-3000 hours (0.3-125 days). Admission diagnoses were intracerebral haemorrhage (N= 13), TBI (N=4), SAH (N=3), ischaemic stroke (N=3) and hypoxic encephalopathy (N=1). The proportion of valid monitoring time spent with secondary insults and the pressure time index (PTI) are presented and discussed. Day 3 and 4 demonstrated the largest number of secondary insults which were mainly hypotension. Patients who progressed to brain death (n = 9) or who died in ICU from cardiac complications (n = 7) exhibited a more severe and sustained hypotensive burden compared with patients alive at discharge (n = 8). This descriptive study proved useful for identifying an optimal window for tracking insults as well as piloting several key summary measures and visualisations which will be utilized in a larger multi-centre study. Conclusions In patients with catastrophic brain injury, the incidence of hypotension remains the highest among systemic secondary insults in patients progressing to brain death and cardiac death.