Research Reports - The frequency of cerebral ischemia/hypoxia in pediatric severe traumatic brain injury
Childs Nerv Syst. 2012 Jun 17
Padayachy LC, Rohlwink U, Zwane E, Fieggen G, Peter JC, Figaji AA
INTRODUCTION: The frequency of adverse events, such as cerebral ischemia,
following traumatic brain injury (TBI) is often debated. Point-in-time monitoring
modalities provide important information, but have limited temporal resolution.
PURPOSE: This study examines the frequency of an adverse event as a point
prevalence at 24 and 72 h post-injury, compared with the cumulative burden
measured as a frequency of the event over the full duration of monitoring.
METHODS: Reduced brain tissue oxygenation (PbtO(2) < 10 mmHg) was the adverse
event chosen for examination. Data from 100 consecutive children with severe TBI
who received PbtO(2) monitoring were retrospectively examined, with data from 87
children found suitable for analysis. Hourly recordings were used to identify
episodes of PbtO(2) less than 10 mmHg, at 24 and 72 h post-injury, and for the
full duration of monitoring. RESULTS: Reduced PbtO(2) was more common early than
late after injury. The point prevalence of reduced PbtO(2) at the selected time
points was relatively low (10 % of patients at 24 h and no patients at the 72-h
mark post-injury). The cumulative burden of these events over the full duration
of monitoring was relatively high: 50 % of patients had episodes of PbtO(2) less
than 10 mmHg and 88 % had PbtO(2) less than 20 mmHg. CONCLUSION: Point-in-time
monitoring in a dynamic condition like TBI may underestimate the overall
frequency of adverse events, like reduced PbtO(2), particularly when compared
with continuous monitoring, which also has limitations, but provides a dynamic
assessment over a longer time period.