Introduction: Cushing’s triad, which implicates bradycardia and hypertension as predictor of raised intracranial pressure (ICP); is a universally followed principle in neurosurgery. For decades, this is relied upon in centers with no facilities of ICP monitoring. However in neurological practice, we frequently encounter otherwise. Hence this study was conducted with an objective to find out whether bradycardia and hypertension actually predicts raised ICP.
Methods: A prospective observational analytical study was conducted during February 2010 till February 2011 to include patients with suspected intracranial hypertension in whom ICP monitoring was performed. Patients with co- existing cardiac disease, sepsis, previous neurological disorders or spinal injuries were excluded. For ICP monitoring, ventricular catheter was placed using standard technique through frontal burr hole. Automatic continuous ICP recordings with corresponding pulse rate (PR), blood pressure (systolic, diastolic and mean) were recorded at one hourly interval. Mean PR and BP before and after the procedure were recorded.
Results: 65 patients who underwent ICP recordings were included. Mean age was 34.9 years (range: 19 to 72 years). 81% patients were males. There were no intra procedural complications except 1 patient who had malposition of catheter. On pearson rank correlation, no significant relationship was seen between ICP and PR or blood pressure. Moreover on mann whitney test, neither bradycardia nor hypertension was seen to significantly associated with rise in intracranial pressure.
Conclusions: Our study suggests that bradycardia and hypertension, alone or in combination are not reliable indicators of raised ICP. Hence it would be rather appropriate to undertake direct ICP monitoring for patients at risk of cerebral herniation.
Patient Care: Rather than depending upon ambiguous clinical parameter to predict raised ICP, this study highlights the need for direct ICP measurement in patients at risk of cerebral herniation.
Learning Objectives: By the end of this presentation, participants should be able to
1. Understand that cushing's triad is not always present in case of raised intracranial pressure.
2. Understand need of direct ICP monitoring in neurosurgical critical care.
3. Discuss the ambiguity of effects on cardiac physiology due to raised intracranial pressure.