Measurement of intracranial pressure and short-term outcomes of patients with traumatic brain injury: a propensity-matched analysis

Craniotomy versus craniectomy for traumatic acute subdural hematoma-coarsened exact matched analysis of outcomes

BACKGROUND AND OBJECTIVES

Acute subdural hematoma (aSDH) after traumatic brain injury frequently requires emergent craniotomy (CO) or decompressive craniectomy (DC). We sought to determine the variables associated with either surgical approach and to compare outcomes between matched patients.

METHODS

A multi-center retrospective review was used to identify traumatic aSDH patients who underwent CO or DC. Patient variables independently associated with surgical approach were used for coarsened exact matching.Multivariate logistic regression and multivariate Cox proportional-hazards regression wereconducted on matched patients to determine independent predictors of mortality.

RESULTS

Seventy-six patients underwent CO and sixty-two underwent DC for aSDH evacuation. DC patients were21.4 years younger (P < 0.001), more likely to be male (80.6 % vs 60.5 %,P = 0.011), and present with GCS ≤ 8 (64.5 % vs 36.8 %,P = 0.001). Age (P < 0.001), epidural hematoma (P = 0.01), skull fracture (P = 0.001), and cisternal effacement (P = 0.02) were independently associated with surgical approach. After coarsened exact matching, DC (P = 0.008), older age (P = 0.007), male sex (P = 0.04), and intraventricular hemorrhage (P = 0.02), were independently associated with inpatient mortality. Multivariate Cox proportional-hazards regression demonstrated that DC was independently associated with mortality at 90-days (P = 0.001) and 1-year post-operation (P = 0.003).

CONCLUSION

aSDH patients who receive surgical evacuation via DC as opposed to CO are younger, more likely to be male, and have worse clinical exam. After controlling for patient differences via coarsened exact matching, DC is independently associated with mortality.

Traumatic Brain Injury in Select Low- and Middle-Income Countries: A Narrative Review of the Literature

Low- and middle-income countries (LMICs) experience the majority of traumatic brain injuries (TBIs), yet few studies have examined the epidemiology and management strategies of TBI in LMICs. The objective of this narrative review is to discuss the epidemiology of TBI within LMICs, describe the adherence to Brain Trauma Foundation (BTF) guidelines for the management of severe TBI in LMICs, and document TBI management strategies currently used in LMICs. Articles from January 1, 2009 to September 30, 2021 that included patients with TBI greater than 18 years of age in low-, low middle-, and high middle-income countries were queried in PubMed. Search results demonstrated that TBI in LMICs mostly impacts young males involved in road traffic accidents. Within LMICs there are a myriad of approaches to managing TBI with few randomized controlled trials performed within LMICs to evaluate those interventions. More studies are needed in LMICs to establish the effectiveness and appropriateness of BTF guidelines for managing TBI and to help identify methods for managing TBI that are appropriate in low-resource settings. The problem of limited pre- and post-hospital care is a bigger challenge that needs to be considered while addressing management of TBI in LMICs.

A Novel Noninvasive Technique for Intracranial Pressure Waveform Monitoring in Critical Care

BACKGROUND

We validated a new noninvasive tool (B4C) to assess intracranial pressure waveform (ICPW) morphology in a set of neurocritical patients, correlating the data with ICPW obtained from invasive catheter monitoring.

MATERIALS AND METHODS

Patients undergoing invasive intracranial pressure (ICP) monitoring were consecutively evaluated using the B4C sensor. Ultrasound-guided manual internal jugular vein (IJV) compression was performed to elevate ICP from the baseline. ICP values, amplitudes, and time intervals (P2/P1 ratio and time-to-peak [TTP]) between the ICP and B4C waveform peaks were analyzed.

RESULTS

Among 41 patients, the main causes for ICP monitoring included traumatic brain injury, subarachnoid hemorrhage, and stroke. Bland-Altman's plot indicated agreement between the ICPW parameters obtained using both techniques. The strongest Pearson's correlation for P2/P1 and TTP was observed among patients with no cranial damage (r = 0.72 and 0.85, respectively) to the detriment of those who have undergone craniotomies or craniectomies. P2/P1 values of 1 were equivalent between the two techniques (area under the receiver operator curve [AUROC], 0.9) whereas B4C cut-off 1.2 was predictive of intracranial hypertension (AUROC 0.9, p < 000.1 for ICP > 20 mmHg).

CONCLUSION

B4C provided biometric amplitude ratios correlated with ICPW variation morphology and is useful for noninvasive critical care monitoring.

Transfusion requirements after head trauma: a randomized feasibility controlled trial

Background

Anemia is frequent among patients with traumatic brain injury (TBI) and is associated with an increased risk of poor outcome. The optimal hemoglobin concentration to trigger red blood cell (RBC) transfusion in patients with TBI is not clearly defined.

Methods

All eligible consecutive adult patients admitted to the intensive care unit (ICU) with moderate or severe TBI were randomized to a “restrictive” (hemoglobin transfusion threshold of 7 g/dL), or a “liberal” (threshold 9 g/dL) transfusion strategy. The transfusion strategy was continued for up to 14 days or until ICU discharge. The primary outcome was the mean difference in hemoglobin between groups. Secondary outcomes included transfusion requirements, intracranial pressure management, cerebral hemodynamics, length of stay, mortality and 6-month neurological outcome.

Results

A total of 44 patients were randomized, 21 patients to the liberal group and 23 to the restrictive group. There were no baseline differences between the groups. The mean hemoglobin concentrations during the 14-day period were 8.4 ± 1.0 and 9.3 ± 1.3 (p < 0.01) in the restrictive and liberal groups, respectively. Fewer RBC units were administered in the restrictive than in the liberal group (35 vs. 66, p = 0.02). There was negative correlation (r = − 0.265, p < 0.01) between hemoglobin concentration and middle cerebral artery flow velocity as evaluated by transcranial Doppler ultrasound and the incidence of post-traumatic vasospasm was significantly lower in the liberal strategy group (4/21, 3% vs. 15/23, 65%; p < 0.01). Hospital mortality was higher in the restrictive than in the liberal group (7/23 vs. 1/21; p = 0.048) and the liberal group tended to have a better neurological status at 6 months (p = 0.06).

Conclusions

The trial reached feasibility criteria. The restrictive group had lower hemoglobin concentrations and received fewer RBC transfusions. Hospital mortality was lower and neurological status at 6 months favored the liberal group.

Trial registration

ClinicalTrials.gov, NCT02203292. Registered on 29 July 2014.

Electronic supplementary material

The online version of this article (10.1186/s13054-018-2273-9) contains supplementary material, which is available to authorized users.

Intracranial pressure monitoring in diffuse brain injury-why the developing world needs it more?

BACKGROUND

Use of ICP monitoring is considered to be part of "standard of care" in management of severe traumatic brain injury, but it is rarely used in developing countries. The authors present a study which evaluates the efficacy and outcomes of ICP monitoring at a high-volume trauma center in India.

METHODS

Data on management and outcomes for 126 patients who were admitted with diffuse traumatic 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.

RESULTS

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.

CONCLUSIONS

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.

Hydrocephalus: the role of cerebral aquaporin-4 channels and computational modeling considerations of cerebrospinal fluid

Aquaporin-4 (AQP4) channels play an important role in brain water homeostasis. Water transport across plasma membranes has a critical role in brain water exchange of the normal and the diseased brain. AQP4 channels are implicated in the pathophysiology of hydrocephalus, a disease of water imbalance that leads to CSF accumulation in the ventricular system. Many molecular aspects of fluid exchange during hydrocephalus have yet to be firmly elucidated, but review of the literature suggests that modulation of AQP4 channel activity is a potentially attractive future pharmaceutical therapy. Drug therapy targeting AQP channels may enable control over water exchange to remove excess CSF through a molecular intervention instead of by mechanical shunting. This article is a review of a vast body of literature on the current understanding of AQP4 channels in relation to hydrocephalus, details regarding molecular aspects of AQP4 channels, possible drug development strategies, and limitations. Advances in medical imaging and computational modeling of CSF dynamics in the setting of hydrocephalus are summarized. Algorithmic developments in computational modeling continue to deepen the understanding of the hydrocephalus disease process and display promising potential benefit as a tool for physicians to evaluate patients with hydrocephalus.