Introduction: Traumatic brain injury is a major cause of mortality and morbidity. Secondary brain insult occurs as a result of cerebral ischaemia and is preventable. Cerebral MD provides a method of measuring parameters that predict cerebral ischemia before signs and symptoms arise.
Methods: This is a single center observational study of 19 patients aged between 22 and 45 years (16 males, 3 females) of severe traumatic brain injury at our center from 2013-2014. All patients underwent decompressive craniectomy with placement of MD catheters in peri-contusional tissue and were monitored on an hourly basis for 3-5 days.
Results: Consistently high LP ratios were seen in peri-contusional tissues with average values ranging from 19.5 to 134. Average glucose values ranged from 0.5 to 4.2 with a mean of 1.7 mmol/l. Average glycerol values showed maximum variation ranging from 14 to 1395 with a mean of 314. Average ICP ranged from 3.7 to 29. RBS values ranged from 5.7 to 9.1 mmol/l (102.6 - 164mg%). Variables were assessed as predictors of M score at end of microdialysis period. Significant correlation was found between LG and LP ratio (Pearson’s coefficient .846 with p=0.000) and between Glycerol and LP ratio (Pearson’s coefficient .475 with p=0.03). Average ICP and M score showed pearson’s coefficent of -0.154 but was not significant. The other entire variables i.e. average LP ratio, LG ratio, Glucose and Glycerol did not show any significant correlation with M score at the end of microdialysis. No significant correlation was found between RBS and cerebral glucose values.
Conclusions: Cerebral MD variables (glycerol, LG and LP) correlated with one another which may indicate a consistent metabolic derangement. Whether MD variables affect a more long-term outcome remains to be seen. Surprisingly, higher blood sugar values did not correlate with higher brain glucose values.
Patient Care: Cerebral microdialysis can be used as a prognostic tool in head injured if we can distinguish between ischemia and mitochondrial dysfunction.
Learning Objectives: To study value of cerebral microdialysis in traumatic brain injured : a research or prognostic tool.