Related Experiment Videos
Cerebrospinal fluid flow dynamics in children with external ventricular drains
J M Drake1, C Sainte-Rose, M DaSilva
1Division of Neurosurgery, Hospital For Sick Children, University of Toronto, Ontario, Canada.
Insights
Cerebrospinal fluid (CSF) shunt infections in children treated with external ventricular drains (EVDs) showed variable CSF output. Factors like age, weight, and infection type influenced drainage, with infections potentially reducing CSF production.
Area of Science:
- Pediatric Neurosurgery
- Infectious Diseases
- Biomedical Engineering
Background:
- Cerebrospinal fluid (CSF) shunt infections are a common complication in pediatric neurosurgery.
- External ventricular drains (EVDs) are crucial for managing CSF pressure in infected shunts.
- Understanding CSF dynamics during infection is vital for optimizing treatment.
Purpose of the Study:
- To analyze the characteristics of CSF output from EVDs in children with shunt infections.
- To identify factors influencing CSF production and drainage in this patient population.
- To correlate CSF output with patient factors and infection parameters.
Main Methods:
- Retrospective analysis of 64 EVD placements in 55 children with CSF shunt infections.
- Continuous, second-by-second CSF output monitoring using a computer system for up to 24 hours in 9 children.
- Simultaneous recording of patient arousal state and daily EVD output measurements.
- Statistical analysis relating EVD output to age, sex, weight, drip chamber height, time since insertion, and infecting organism.
Main Results:
- Mean EVD flow rate was 6.3 ml/h, with significant fluctuations and periods of flow arrest observed via computer monitoring.
- EVD output increased with patient age and weight.
- Gram-negative or polymicrobial infections and higher drip chamber levels were associated with decreased EVD output.
- Patient arousal state showed variable correlation with CSF flow rate changes.
Conclusions:
- Human CSF production increases with brain growth.
- Gram-negative and polymicrobial infections appear to depress CSF production.
- EVD flow rates in the supine position are comparable to implanted CSF shunts.
- CSF drainage requirements in infected shunt cases approximate measured EVD outputs.
Abstract:
Fifty-five children had 64 external ventricular drains (EVDs) placed predominantly (95%) for cerebrospinal fluid (CSF) shunt infections. In 9 children, a computer monitoring system measured the CSF output each second continuously for up to 24 hours. The monitoring was repeated daily for up to 9 days. The state of arousal of the patients was recorded simultaneously. In all children, daily EVD outputs were related to age, sex, weight, method of establishing the EVD, height of the drip chamber, time since insertion, and type of infecting organism. Computer monitoring revealed wide fluctuations in flow rate, with peak rates frequently greater than 20 ml/h and periods of flow arrest. These changes were usually associated with increased arousal, but also occurred with sleep. The mean EVD flow rate for all children was 6.3 ml/h. EVD output increased with age and weight. EVD output decreased with Gram-negative or multiple-organism infections and with elevation of the drip chamber. Resolution of the infection, sex of the patient, and method of establishing the EVD had no effect on output. These results predict that CSF production increases with brain growth in humans: that CSF production is depressed by Gram-negative and multiple-organism infections: that implanted CSF shunts with standard valves flow at equivalent rates to an EVD in the supine position; and that the CSF drainage requirements in this group are approximately equal to their EVD outputs.