Intracranial pressure monitoring for severe traumatic brain injury case series
2018
Data on management and outcomes for 126 patients who were admitted with traumatic diffuse brain injury (GCS 3-8) were studied prospectively over an 18-month period. These patients were treated by one of the two specific protocols: ICP monitoring-based or non-ICP monitoring-based. The primary outcome was measured based on 2 weeks mortality and GOS-E at 1, 3, and 6 months. Secondary outcome was measured based on need for brain-specific treatment, length of ICU stay, and radiation exposure.
Mortality in a subset of patients who underwent surgical intervention later due to increased ICP values, drop in GCS, or radiological deterioration was noted to be significantly lower in the ICP monitoring group (p = 0.03), in spite of statistically insignificant difference in overall mortality rates between groups. GOS-E scores at 1 month were significantly better (p = 0.033) in ICP monitoring group, even though they equalized at 3 and 6 months. The need for brain-specific treatment (p < 0.001), radiation exposure (p < 0.001), and length of ICU stay (p = 0.013) was significantly lower in the ICP monitoring group.
ICP monitoring-based treatment protocol helps in achieving faster recovery; lowers mortality rates in operated patients; and reduces ICU stay, radiation exposure, and the need for brain-specific treatment 1).
The decision for the decompressive craniectomy in the ICP group was taken only when the raised ICP was not amenable to medical management after appropriate time depending on the mode of medical intervention. This time period regarding response to medical management is fairly pharmacologically standardized and does not require further elaboration.
In the non-intracranial pressure-monitoring group, mannitol and hypertonic saline where used depending on the admitting consultants’ choice. Moreover, whenever mannitol was stopped due to renal impairment, other measures including decompressive craniectomy was resorted to depending on the clinical status and radiological finding of the patient the details of which are beyond the scope or purpose of the article. ICP re-zeroing generally does not take more than 15 min and none of the transducer-related problems necessitated patients being off monitoring for more than 10 to 15 min and the one case of transducer-related haemorrhage was not clinically relevant in terms of haemorrhage volume 2).
Though the authors have attempted to evaluate an important topic, i.e., the need for ICP monitoring in diffuse brain injury, there are a few methodological errors and authors have evaluated limited aspects of the problem 3).
2013
A prospective, observational study including patients with severe blunt TBI (Glasgow Coma Scale score ≤ 8, head Abbreviated Injury Scale score ≥ 3) between January 2010 and December 2011. Demographics, clinical characteristics, laboratory profile, head CT scans, injury severity indices, and interventions were collected. The study population was stratified into 2 study groups: ICP monitoring and no ICP monitoring. Primary outcomes included compliance with BTF guidelines, overall in-hospital mortality, and mortality due to brain herniation. Secondary outcomes were ICU and hospital lengths of stay. Multiple regression analyses were deployed to determine the effect of ICP monitoring on outcomes.
A total of 216 patients met the BTF guideline criteria for ICP monitoring. Compliance with BTF guidelines was 46.8% (101 patients). Patients with subarachnoid hemorrhage and those who underwent craniectomy/craniotomy were significantly more likely to undergo ICP monitoring. Hypotension, coagulopathy, and increasing age were negatively associated with the placement of ICP monitoring devices. The overall in-hospital mortality was significantly higher in patients who did not undergo ICP monitoring (53.9% vs 32.7%, adjusted p = 0.019). Similarly, mortality due to brain herniation was significantly higher for the group not undergoing ICP monitoring (21.7% vs 12.9%, adjusted p = 0.046). The ICU and hospital lengths of stay were significantly longer in patients subjected to ICP monitoring.
Compliance with BTF ICP monitoring guidelines in our study sample was 46.8%. Patients managed according to the BTF ICP guidelines experienced significantly improved survival 4).
Data suggest that there is a subset of patients meeting BTF criteria for ICP monitoring that do well without ICP monitoring. This finding should provoke reevaluation of the indication and utility of ICP monitoring in TBI patients 5).
The absence of 24-hour in-house neurosurgery coverage can negatively impact timely monitor placement.
After appropriate training, ICP monitors can be safely placed by trauma surgeons with minimal adverse effects. With current and expected specialty shortages, acute care surgeons can successfully adopt procedures such as ICP monitor placement with minimal complications 6).
Although widely accepted as useful tool in the management of patients with severe head injuries, the role of ICP monitoring in patients with large cerebral infarctions is controversial.
Intracranial pressure monitoring Level IIB
Management of severe traumatic brain injury patients using information from ICP monitoring is recommended to reduce inhospital and 2-week post-injury mortality.
Recommendations from the prior (Third) Edition not supported by evidence meeting current standards. ICP should be monitored in all salvageable patients with a TBI (GCS 3-8 after resuscitation) and an abnormal CT scan. An abnormal CT scan of the head is one that reveals hematomas, contusions, swelling, herniation, or compressed basal cisterns.
ICP monitoring is indicated in patients with severe TBI with a normal CT scan if ≥ 2 of the following features are noted at admission: age > 40 years, unilateral or bilateral motor posturing, or SBP < 90 mm Hg.
Multimodality monitoring offers neurointensivists the ability to monitor multiple physiologic parameters that act as surrogates of brain ischemia and hypoxia, the major driving forces behind secondary brain injury. The heterogeneity of the pathophysiology of TBI makes it necessary to take into consideration these interacting physiologic factors when recommending for or against any therapies; it may also account for the failure of all the neuroprotective therapies studied so far 7).
Care focused on maintaining monitored intracranial pressure (ICP) at 20 mm Hg or less was not shown to be superior to care based on imaging and clinical examination 8). , but ICP and cerebral perfusion pressure therapy remain important in care.
While acknowledging difficulties in conducting robust prospective randomized studies in this area, such high-quality evidence for the utility of ICP/cerebral perfusion pressure CPP-directed therapy is urgently required. So, too, is the wider adoption of multimodality neuromonitoring to guide optimal management of ICP and CPP, and a greater understanding of the underlying pathophysiology of the different forms of sTBI and what exactly the different monitoring tools used actually represent 9).
Although high-quality evidence for Multimodal neuromonitoring in the neurosurgical patient requires insertion of probes through multiple craniostomies.]] is limited, it should be more widely adapted to better understand the complex pathophysiology after severe TBI, better target care, and identify new therapeutic opportunities 10).