Cerebral Autoregulation in Non-Brain Injured Patients: A Systematic Review

The use of ketamine in patients with TBI has often been argued due to its possible deleterious effects on cerebral circulation and perfusion. Early studies suggested that ketamine could increase intracranial pressure, decreasing cerebral perfusion pressure and thereby reducing oxygen supply to the damaged cerebral cortex. Some recent studies have refuted these conclusions relating to the role of ketamine, especially in patients with TBI, showing that ketamine should be the first-choice drug in this type of patient at induction. Our narrative review collects evidence on ketamine’s use in patients with TBI. Databases were examined for studies in which ketamine had been used in acute traumatic brain injury (TBI). The outcomes considered in this narrative review were: mortality of patients with TBI; impact on intracranial pressure and cerebral perfusion pressure; blood pressure and heart rate values; depolarization rate; and preserved neurological functions. 11 recent studies passed inclusion and exclusion criteria and were included in this review. Despite all the benefits reported in the literature, the use of ketamine in patients with brain injury still appears to be limited. A slight increase in intracranial pressure was found in only two studies, while two smaller studies showed a reduction in intracranial pressure after ketamine administration. There was no evidence of harm from the ketamine’s use in patients with TBI.

show abstract

“…Ketamine in an acute setting could not impact cerebral autoregulation: a delicate mechanism altered in acute brain injury [ 57 ].…”

Section: Resultsmentioning

confidence: 99%

Ketamine in Acute Brain Injury: Current Opinion Following Cerebral Circulation and Electrical Activity

et al. 2022

Self Cite

View full text Add to dashboard Cite

show abstract

“…In cases of increased ICP, the self-regulation system and brain compliance maintain intracranial pressure level within physiological limit allowing an adequate cerebral perfusion pressure. In severe TBI, the loss of the cerebral compliance causes intracranial hypertension syndrome and brain herniations [ 9 ].…”

Section: Discussionmentioning

confidence: 99%

Decompressive Craniectomy in Severe Traumatic Brain Injury: The Intensivist’s Point of View

et al. 2023

Self Cite

View full text Add to dashboard Cite

Introduction: Traumatic brain injury (TBI) represents a severe pathology with important social and economic concerns, decompressive craniectomy (DC) represents a life-saving surgical option to treat elevated intracranial hypertension (ICP). The rationale underlying DC is to remove part of the cranial bones and open the dura mater to create space, avoiding secondary parenchymal damage and brain herniations. The scope of this narrative review is to summarize the most relevant literature and to discuss main issues about indication, timing, surgical procedure, outcome, and complications in adult patients involved in severe traumatic brain injury, underwent to the DC. The literature research is made with Medical Subject Headings (MeSH) terms on PubMed/MEDLINE from 2003 to 2022 and we reviewed the most recent and relevant articles using the following keywords alone or matched with each other: decompressive craniectomy; traumatic brain injury; intracranial hypertension; acute subdural hematoma; cranioplasty; cerebral herniation, neuro-critical care, neuro-anesthesiology. The pathogenesis of TBI involves both primary injuries that correlate directly to the external impact of the brain and skull, and secondary injuries due to molecular, chemical, and inflammatory cascade inducing further cerebral damage. The DC can be classified into primary, defined as bone flap removing without its replacement for the treatment of intracerebral mass, and secondary, which indicates for the treatment of elevated intracranial pressure (ICP), refractory to intensive medical management. Briefly, the increased brain compliance following bone removal reflects on CBF and autoregulation inducing an alteration in CSF dynamics and so, eventual complications. The risk of complications is estimated around 40%. The main cause of mortality in DC patients is due to brain swelling. In traumatic brain injury, primary or secondary decompressive craniectomy is a life-saving surgery, and the right indication should be mandatory in multidisciplinary medical–surgical consultation.

show abstract

“…More recently, the application of neuromonitoring tools able to assess CA has been applied in a variety of situations outside the neurocritical care settings. A recent systematic review found 22 articles exploring the role of monitoring CA in the perioperative settings, in ICU patients with sepsis, and in the pediatric population, suggesting that even in patients without brain injury, altered CA may result in increased mortality [ 30 ]. In addition, disturbed CA was found as a common event, as it is reported in about 50% of patients in the general ICU [ 31 ].…”

Section: Discussionmentioning

confidence: 99%

Cerebral Autoregulation, Cerebral Hemodynamics, and Injury Biomarkers, in Patients with COVID-19 Treated with Veno-Venous Extracorporeal Membrane Oxygenation

et al. 2023

Self Cite

View full text Add to dashboard Cite

Background This study aimed to describe the cerebrovascular dynamics, in particular cerebral autoregulation (CA), and cerebral biomarkers as neuron-specific enolase (NSE) in patients with a diagnosis of coronavirus disease 2019 and acute respiratory distress syndrome as well as undergoing veno-venous extracorporeal membrane treatment. Methods This was a single center, observational study conducted in the intensive care unit of the University Hospital in Wroclaw from October 2020 to February 2022. Transcranial Doppler recordings of the middle cerebral artery conducted for at least 20 min were performed. Cerebral autoregulation (CA) was estimated by using the mean velocity index (Mxa), calculated as the moving correlation coefficient between slow-wave oscillations in cerebral blood flow velocity and arterial blood pressure. Altered CA was defined as a positive Mxa. Blood samples for the measurement of NSE were obtained at the same time as transcranial Doppler measurements. Results A total of 16 patients fulfilled the inclusion criteria and were enrolled in the study. The median age was 39 (34–56) years. Altered CA was found in 12 patients, and six out of seven patients who died had altered CA. A positive Mxa was a significant predictor of mortality, with a sensitivity of 85.7%. We found that three out of five patients with pathological changes in brain computed tomography and six out of ten patients with neurological complications had altered CA. NSE was a significant predictor of mortality (cutoff value: 28.9 µg/L); area under the curve = 0.83, p = 0.006), with a strong relationship between increased level of NSE and altered CA, χ2 = 6.24; p = 0.035; φ = 0.69. Conclusions Patients with coronavirus disease 2019–related acute respiratory distress syndrome, requiring veno-venous extracorporeal membrane treatment, are likely to have elevated NSE levels and altered CA. The CA was associated with NSE values in this group. This preliminary analysis suggests that advanced neuromonitoring and evaluation of biomarkers should be considered in this population.

show abstract

Cerebral Autoregulation in Non-Brain Injured Patients: A Systematic Review

Cited by 16 publications

References 33 publications

Ketamine in Acute Brain Injury: Current Opinion Following Cerebral Circulation and Electrical Activity

Ketamine in Acute Brain Injury: Current Opinion Following Cerebral Circulation and Electrical Activity

Decompressive Craniectomy in Severe Traumatic Brain Injury: The Intensivist’s Point of View

Cerebral Autoregulation, Cerebral Hemodynamics, and Injury Biomarkers, in Patients with COVID-19 Treated with Veno-Venous Extracorporeal Membrane Oxygenation

Contact Info

Product

Resources

About