ICP management in patients suffering from traumatic brain injury: a systematic review of randomized controlled trials

Development and Validation of a Neuro-Intensive Care Protocol for Traumatic Brain Injury Management

Introduction Traumatic brain injury (TBI) is a global public health concern with high mortality and disability rates, particularly among younger populations. Structured treatment protocols might improve outcomes and reduce mortality. This study aims to develop and validate the Neuro-Intensive Care Protocol for TBI (NICP-TBI) using the Medical Research Council framework for designing and evaluating complex interventions. Methods The protocol was developed using a systematic literature review, expert consensus, and validation. A 15-member multidisciplinary expert consensus group used the Delphi consensus method to refine the protocol, achieving a consensus threshold of 80%. Validation involved a seven-member expert group evaluating the protocol's relevance, clarity, comprehensiveness, and appropriateness using a five-point Likert scale. The Content Validity Index (CVI) was calculated. Results The NICP-TBI incorporated interventions from clinical practice guidelines and evidence-based protocols. It established clear treatment goals and interventions for each parameter concerned such as airway, ventilation, systemic and cerebral perfusion, intracranial pressure (ICP), sedation, seizure prophylaxis, fluid management, nutrition, infection prophylaxis, temperature management, venous thromboembolism (VTE), blood glucose management, positioning, tapering treatment and family involvement in care. The protocol used a tiered structure adaptable to resource-limited settings. The Delphi process reached a 99.2% final consensus after five rounds, and the CVI was determined to be 1, confirming high validity. Conclusions The NICP-TBI provides a structured, evidence-based framework for managing moderate and severe TBI. The protocol's consensus-driven development, tiered approach in management, and expert validation ensure its applicability across diverse clinical settings, including resource-limited environments. This study highlights the importance of expert consensus and validation in developing effective critical care protocols.

Global traumatic brain injury intracranial pressure: from monitoring to surgical decision

Traumatic brain injury (TBI) is a significant global public health issue, heavily impacting human health, especially in low-and middle-income areas. Despite numerous guidelines and consensus statements, TBI fatality rates remain high. The pathogenesis of severe TBI is closely linked to rising intracranial pressure (ICP). Elevated intracranial pressure can lead to cerebral herniation, resulting in respiratory and circulatory collapse, and ultimately, death. Managing intracranial pressure (ICP) is crucial in neuro-intensive care. Timely diagnosis and precise treatment of elevated ICP are essential. ICP monitoring provides real-time insights into a patient's condition, offering invaluable guidance for comprehensive management. ICP monitoring and standardization can effectively reduce secondary nerve damage, lowering morbidity and mortality rates. Accurately assessing and using true ICP values to manage TBI patients still depends on doctors' clinical experience. This review discusses: (a) Epidemiological disparities of traumatic brain injuries across countries with different income levels worldwide; (b) The significance and function of ICP monitoring; (c) Current status and challenges of ICP monitoring; (d) The impact of decompressive craniectomy on reducing intracranial pressure; and (e) Management of TBI in diverse income countries. We suggest a thorough evaluation of ICP monitoring, head CT findings, and GCS scores before deciding on decompressive craniectomy. Personalized treatment should be emphasized to assess the need for surgical decompression in TBI patients, offering crucial insights for clinical decision-making.

External Ventricular Drains versus Intraparenchymal Pressure Monitors in the Management of Moderate to Severe Traumatic Brain Injury: Experience at Two Academic Centers over a Decade

OBJECTIVE

The choice between external ventricular drain (EVD) and intraparenchymal monitor (IPM) for managing intracranial pressure in moderate-to-severe traumatic brain injury (msTBI) patients remains controversial. This study aimed to investigate factors associated with receiving EVD versus IPM and to compare outcomes and clinical management between EVD and IPM patients.

METHODS

Adult msTBI patients at 2 similar academic institutions were identified. Logistic regression was performed to identify factors associated with receiving EVD versus IPM (model 1) and to compare EVD versus IPM in relation to patient outcomes after controlling for potential confounders (model 2), through odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

Of 521 patients, 167 (32.1%) had EVD and 354 (67.9%) had IPM. Mean age, sex, and Injury Severity Score were comparable between groups. Epidural hemorrhage (EDH) (OR 0.43, 95% CI 0.21-0.85), greater midline shift (OR 0.90, 95% CI 0.82-0.98), and the hospital with higher volume (OR 0.14, 95% CI 0.09-0.22) were independently associated with lower odds of receiving an EVD whereas patients needing a craniectomy were more likely to receive an EVD (OR 2.04, 95% CI 1.12-3.73). EVD patients received more intense medical treatment requiring hyperosmolar therapy compared to IPM patients (64.1% vs. 40.1%). No statistically significant differences were found in patient outcomes.

CONCLUSIONS

While EDH, greater midline shift, and hospital with larger patient volume were associated with receiving an IPM, the need for a craniectomy was associated with receiving an EVD. EVD patients received different clinical management than IPM patients with no significant differences in patient outcomes.

Prediction of Increased Intracranial Pressure in Traumatic Brain Injury Using Quantitative Electroencephalogram in a Porcine Experimental Model

Continuous and non-invasive measurement of intracranial pressure (ICP) in traumatic brain injury (TBI) is important to recognize increased ICP (IICP), which can reduce treatment delays. The purpose of this study was to develop an electroencephalogram (EEG)-based prediction model for IICP in a porcine TBI model. Thirty swine were anaesthetized and underwent IICP by inflating a Foley catheter in the intracranial space. Single-channel EEG data were collected every 6 min in 10 mmHg increments in the ICP from baseline to 50 mmHg. We developed EEG-based models to predict the IICP (equal or over 25 mmHg) using four algorithms: logistic regression (LR), naive Bayes (NB), support vector machine (SVM), and random forest (RF). We assessed the performance of each model based on the accuracy, sensitivity, specificity, and AUC values. The accuracy of each prediction model for IICP was 0.773 for SVM, 0.749 for NB, 0.746 for RF, and 0.706 for LR. The AUC of each model was 0.860 for SVM, 0.824 for NB, 0.802 for RF, and 0.748 for LR. We developed a machine learning prediction model for IICP using single-channel EEG signals in a swine TBI experimental model. The SVM model showed good predictive power with the highest AUC value.

Impact of Intracranial Hypertension on Outcome of Severe Traumatic Brain Injury Pediatric Patients: A 15-Year Single Center Experience

Background: Intracranial hypertension (IC-HTN) is significantly associated with higher risk for an unfavorable outcome in pediatric trauma. Intracranial pressure (ICP) monitoring is widely becoming a standard of neurocritical care for children. Methods: The present study was designed to evaluate influences of IC-HTN on clinical outcomes of pediatric TBI patients. Demographic, injury severity, radiologic characteristics were used as possible predictors of IC-HTN or of functional outcome. Results: A total of 118 pediatric intensive care unit (PICU) patients with severe TBI (sTBI) were included. Among sTBI cases, patients with GCS < 5 had significantly higher risk for IC-HTN and for mortality. Moreover, there was a statistically significant positive correlation between IC-HTN and severity scoring systems. Kaplan−Meier analysis determined a significant difference for good recovery among patients who had no ICP elevations, compared to those who had at least one episode of IC-HTN (log-rank chi-square = 11.16, p = 0.001). A multivariable predictive logistic regression analysis distinguished the ICP-monitored patients at risk for developing IC-HTN. The model finally revealed that higher ISS and Helsinki CT score increased the odds for developing IC-HTN (p < 0.05). Conclusion: The present study highlights the importance of ICP-guided clinical practices, which may lead to increasing percentages of good recovery for children.

An overview of systematic reviews on the pharmacological randomized controlled trials for reducing intracranial pressure after traumatic brain injury

BACKGROUND

There is a need for an overview of systematic reviews (SRs) examining randomized clinical trials (RCTs) of pharmacological interventions in the treatment of intracranial pressure (ICP) post-TBI.

OBJECTIVES

To summarize pharmacological effectiveness in decreasing ICP in SRs with RCTs and evaluate study quality.

METHODS

Comprehensive literature searches were conducted in MEDLINE, PubMed, EMBASE, PsycINFO, and Cochrane Library databases for English SRs through October 2020. Inclusion criteria were SRs with RCTs that examined pharmacological interventions to treat ICP in patients post-TBI. Data extracted were participant characteristics, pharmacological interventions, and ICP outcomes. Study quality was assessed with AMSTAR-2.

RESULTS

Eleven SRs between 2003 and 2020 were included. AMSTAR-2 ratings revealed 3/11 SRs of high quality. Pharmacological interventions included hyperosmolars, neuroprotectives, anesthetics, sedatives, and analgesics. Study samples ranged from 7 to 1282 patients. Hyperosmolar agents and sedatives were beneficial in lowering elevated ICP. High bolus dose opioids had a more deleterious effect on ICP. Neuroprotective agents did not show any effects in ICP management. RCT sample sizes and findings in the SRs varied. A lack of detailed data syntheses was noted. AMSTAR-2 analysis revealed moderate-to-high quality in most SRs. Future SRs may focus on streamlined reporting of dosing and clearer clinical recommendations.

CONCLUSIONS

PROSPERO-Registration: CRD42015017355.

Effect of Low Frequency Repetitive Transcranial Magnetic Stimulation (rTMS) Combined with Hyperbaric Oxygen (HBO) on Awakening of Coma Patients with Traumatic Brain Injury

Coma caused by craniocerebral injury is a common condition of neurosurgical acute injury. There is no specific method to promote awakening in a clinic. Early comprehensive treatment may be helpful to patients. The common methods are hyperbaric oxygen (HBO) and low-frequency repetitive transcranial magnetic stimulation (rTMS). However, the application effect and mechanism of rTMS combined with HBO on coma patients with traumatic brain injury need to be further studied. The brain stem auditory evoked potential (BAEP) is examined by the Kennedy coma recovery scale (CRS-R), the recovery of brain function and the state of consciousness are evaluated, and the therapeutic effect is evaluated by the Glasgow Coma Scale (GCS). Cerebrospinal fluid NE level, MCA blood flow velocity, and left brainstem and right brainstem auditory evoked potential are used to evaluate brain rehabilitation. RTMS combined with HBO could shorten the wake-up time, improve the wake-up rate, improve the GCS score and CRS-R score, shorten the brain wave latency time of the left and right brainstem, increase the NE level of cerebrospinal fluid, and decrease the blood flow velocity of MCA. RTMS combines with HBO can improve the nerve excitability of brain cells, reduce the disturbance of consciousness, promote the functional recovery of brain injury, and has a certain role in promoting the awakening of patients with traumatic brain injury coma.

Foundations of Time Series Analysis

For almost a century, classical statistical methods including exponential smoothing and autoregression integrated moving averages (ARIMA) have been predominant in the analysis of time series (TS) and in the pursuit of forecasting future events from historical data. TS are chronological sequences of observations, and TS data are therefore prevalent in many aspects of clinical medicine and academic neuroscience. With the rise of highly complex and nonlinear datasets, machine learning (ML) methods have become increasingly popular for prediction or pattern detection and within neurosciences, including neurosurgery. ML methods regularly outperform classical methods and have been successfully applied to, inter alia, predict physiological responses in intracranial pressure monitoring or to identify seizures in EEGs. Implementing nonparametric methods for TS analysis in clinical practice can benefit clinical decision making and sharpen our diagnostic armory.

Improving post-cardiac arrest cerebral perfusion pressure by elevating the head and thorax

AIM

The optimal head and thorax position after return of spontaneous circulation (ROSC) following cardiac arrest (CA) is unknown. This study examined whether head and thorax elevation post-ROSC is beneficial, in a porcine model.

METHODS

Protocol A: 40 kg anesthetized pigs were positioned flat, after 7.75 min of untreated CA the heart and head were elevated 8 and 12 cm, respectively, above the horizontal plane, automated active compression decompression (ACD) plus impedance threshold device (ITD) CPR was started, and 2 min later the heart and head were elevated 10 and 22 cm, respectively, over 2 min to the highest head up position (HUP). After 30 min of CPR pigs were defibrillated and randomized 10 min later to four 5-min epochs of HUP or flat position. Multiple physiological parameters were measured. In Protocol B, after 6 min of untreated VF, pigs received 6 min of conventional CPR flat, and after ROSC were randomized HUP versus Flat as in Protocol A. The primary endpoint was cerebral perfusion pressure (CerPP). Multivariate analysis-of-variance (MANOVA) for repeated measures was used. Data were reported as mean ± SD.

RESULTS

In Protocol A, intracranial pressure (ICP) (mmHg) was significantly lower post-ROSC with HUP (9.1 ± 5.5) versus Flat (18.5 ± 5.1) (p < 0.001). Conversely, CerPP was higher with HUP (62.5 ± 19.9) versus Flat (53.2 ± 19.1) (p = 0.004), respectively. Protocol A and B results comparing HUP versus Flat were similar.

CONCLUSION

Post-ROSC head and thorax elevation in a porcine model of cardiac arrest resulted in higher CerPP and lower ICP values, regardless of VF duration or CPR method.

IACUC PROTOCOL NUMBER

19-09.

Low-Value Clinical Practices in Adult Traumatic Brain Injury: An Umbrella Review

Despite numerous interventions and treatment options, the outcomes of traumatic brain injury (TBI) have improved little over the last 3 decades, which raises concern about the value of care in this patient population. We aimed to synthesize the evidence on 14 potentially low-value clinical practices in TBI care. Using umbrella review methodology, we identified systematic reviews evaluating the effectiveness of 14 potentially low-value practices in adults with acute TBI. We present data on methodological quality (Assessing the Methodological Quality of Systematic Reviews), reported effect sizes, and credibility of evidence (I to IV). The only clinical practice with evidence of benefit was therapeutic hypothermia (credibility of evidence II to IV). However, the most recent meta-analysis on hypothermia based on high-quality trials suggested harm (credibility of evidence IV). Meta-analyses on platelet transfusion for patients on antiplatelet therapy were all consistent with harm but were statistically non-significant. For the following practices, effect estimates were consistently close to the null: computed tomography (CT) in adults with mild TBI who are low-risk on a validated clinical decision rule; repeat CT in adults with mild TBI on anticoagulant therapy with no clinical deterioration; antibiotic prophylaxis for external ventricular drain placement; and decompressive craniectomy for refractory intracranial hypertension. We identified five clinical practices with evidence of lack of benefit or harm. However, evidence could not be considered to be strong for any clinical practice as effect measures were imprecise and heterogeneous, systematic reviews were often of low quality, and most included studies had a high risk of bias.

Immunomodulatory Effect of Hypertonic Saline Solution in Traumatic Brain-Injured Patients and Intracranial Hypertension

Traumatic brain injury (TBI) is often associated with an increase in the intracranial pressure (ICP). This increase in ICP can cross the physiological range and lead to a reduction in cerebral perfusion pressure (CPP) and the resultant cerebral blood flow (CBF). It is this reduction in the CBF that leads to the secondary damage to the neural parenchyma along with the physical axonal and neuronal damage caused by the mass effect. In certain cases, a surgical intervention may be required to either remove the mass lesion (hematoma of contusion evacuation) or provide more space to the insulted brain to expand (decompressive craniectomy). Whether or not a surgical intervention is performed, all these patients require some form of pharmaceutical antiedema agents to bring down the raised ICP. These agents have been broadly classified as colloids (e.g., mannitol, glycerol, urea) and crystalloids (e.g., hypertonic saline), and have been used since decades. Even though mannitol has been the workhorse for ICP reduction owing to its unique properties, crystalloids have been found to be the preferred agents, especially when long-term use is warranted. The safest and most widely used agent is hypertonic saline in various concentrations. Whatever be the concentration, hypertonic saline has created special interest among physicians owing to its additional property of immunomodulation and neuroprotection. In this review, we summarize and understand the various mechanism by which hypertonic saline exerts its immunomodulatory effects that helps in neuroprotection after TBI.

Management of Intracranial Pressure Part II: Nonpharmacologic Interventions

Pharmacologic and nonpharmacologic interventions are available to treat patients who experience serious elevations in intracranial pressure (ICP). In some cases, patients may experience ICP that is refractory to treatment. Significant negative effects on cerebral blood flow, tissue oxygenation, and cerebral metabolism occur as a result of intracranial hypertension, leading to secondary brain injury. In part 2 of this series, nonpharmacologic interventions for ICP and ICP refractory to treatment are discussed. Interventions include neurologic monitoring (bedside assessment and multimodal monitoring), ventilatory support, fluid and electrolyte maintenance, targeted temperature management, and surgical intervention. Technology is always evolving, and the focus of multimodal monitoring here includes devices to monitor ICP, brain tissue oxygen tension, and cerebral blood flow and cerebral microdialysis monitors. Nursing care of these patients includes perspicacious assessment and integration of data, monitoring ventilatory and hemodynamic functioning, and appropriate patient positioning. Nurses must collaborate with the interprofessional care team to ensure favorable patient outcomes while utilizing an evidence-based guideline for the management of ICP.

Decompressive craniectomy protects against hippocampal edema and behavioral deficits at an early stage of a moderately controlled cortical impact brain injury model in adult male rats

A decompressive craniectomy (DC) has been shown to be a life-saving therapeutic treatment for traumatic brain injury (TBI) patients, which also might result in post-operative behavioral dysfunction. However, there is still no definite conclusion about whether the behavioral dysfunction already existed at an early stage after the DC operation or is just a long-term post-operation complication. Therefore, the aim of the present study was to analyze whether DC treatment was beneficial to behavioral function at an early stage post TBI. In this study, we established a controlled cortical impact injury rat model to evaluate the therapeutic effect of DC treatment on behavioral deficits at 1 d, 2 d, 3 d and 7 d after TBI. Our results showed that rats suffered significant behavioral and mood deficits after TBI compared to the control group, while decompressive craniectomy treatment could normalize MMP-9 expression levels and reduce hippocampal edema formation, stabilize the expression of Synapsin I, which was a potential indicator of maintaining the hippocampal synaptic function, thus counteracting behavioral but not mood decay in rats subjected to TBI. In conclusion, decompressive craniectomy, excepting for its life-saving effect, could also play a potential beneficial neuroprotective role on behavioral but not mood deficits at an early stage of moderate traumatic brain injury in rats.