Induced hypertension after head injury

Blood Pressure Control in Traumatic Subdural Hematomas

Background There is debate over optimal systolic blood pressure (SBP) after traumatic subdural hematoma. Increased SBP has the benefit of increasing cerebral perfusion pressure and limiting the detrimental secondary effects of traumatic brain injury but poses a risk of hematoma expansion. While prior studies have shown that SBP<90mmHg is associated with worsened morbidity and mortality in subdural hematoma patients, clinical guidelines and expert opinion have differing initial SBP goals. The aim of this study is to leverage a large database to determine the effects of two such goals, namely SBP 100-150mmHg versus SBP<180mmHg in this patient population. Methods A de-identified database network (TriNetX Research Network) was used to retrospectively query all patients with a first instance diagnosis of acute traumatic SDH, who also had a recorded GCS, with maintenance of SBP 100-150 within the first 24 hours (cohort 1) versus patients with an SBP<180 (cohort 2). Data came from 68 health care organizations (HCOs) with a total of 105,897,964 patients on 9/1/2022. The primary outcome of interest was mortality within 30 days. Secondary outcomes include gastrostomy tube placement, craniotomy/craniectomy/burr hole drainage, venous thromboembolism, ischemic stroke, myocardial infarction, seizure, falls, cardiac arrest, and acute kidney injury within 30 days. Cohorts were propensity-score matched for confounders. Results After propensity score matching, 1,243 patients were identified in each cohort. Age at index was 57.97+/-23.21 years and 58.28+/-22.35 years for cohorts 1 and 2, respectively. Mortality was seen in 243 patients (19.756%) vs. 209 (16.992%) (OR 1.203, 95% CI (0.98,1.476), p=0.0767) in cohorts 1 and 2, respectively. There was no statistical difference in secondary outcomes. Conclusion The results of this study demonstrate that the primary outcome of mortality at 30 days is not statistically different in acute traumatic SDH patients, whether their SBP is kept at 100-150 or below 180. Likewise, it shows no statistical difference in the subsequent incidence of gastrostomy tube placement, craniotomy/craniectomy/burr holes, venous thromboembolism, ischemic stroke, myocardial infarction, seizure, falls, or acute kidney injury.

In adult patients with severe traumatic brain injury, does the use of norepinephrine for augmenting cerebral perfusion pressure improve neurological outcome? A systematic review

BACKGROUND AND OBJECTIVE

Despite multiple interventions, mortality due to severe traumatic brain injury (sTBI) within mature Trauma Systems has remained unchanged over the last decade. During this time, the use of vasoactive infusions (commonly norepinephrine) to achieve a target blood pressure and cerebral perfusion pressure (CPP) has been a mainstay of sTBI management. However, evidence suggests that norepinephrine, whilst raising blood pressure, may reduce cerebral oxygenation. This study aimed to review the available evidence that links norepinephrine augmented CPP to clinical outcomes for these patients.

METHODS

A systematic review examining the evidence for norepinephrine augmented CPP in TBI patients was undertaken. Strict inclusion and exclusion criteria were developed for a dedicated literature search of multiple scientific databases. Two dedicated reviewers screened articles, whilst a third dedicated reviewer resolved conflicts.

RESULTS

The systematic review yielded 4,809 articles, of which 1,197 duplicate articles were removed. After abstract/title screening, 45 articles underwent full text review, resulting in the identification of two articles that investigated the effect of norepinephrine administration on clinical outcomes in patients following TBI when compared to other vasopressors. Neither study found a difference in neurological outcome between the vasopressor groups. No articles measured the effect of norepinephrine compared to no vasopressor use on the clinical outcome of patients with sTBI.

CONCLUSIONS

Despite being a mainstay of pharmacological management for hypotension in patients following sTBI, there is minimal clinical evidence supporting the use of norepinephrine in targeting a CPP for either improving neurological outcomes or reducing mortality. Outcomes-based clinical trials exploring the role of brain tissue perfusion and oxygenation monitoring are required to validate any benefit.

Endovascular treatment of acute aortic isthmic rupture: concerning midterm results

BACKGROUND

We evaluated midterm results of endovascular management of traumatic aortic isthmic ruptures.

METHODS

Between 2001 and 2008, 10 patients (seven males, mean age 38 years) underwent endovascular treatment of an acute aortic rupture. Eight procedures were emergent, with four cases of hemodynamic instability with Glasgow scores of 3, 5, and 7. Associated traumas were severe brain, liver, and pelvic bone injuries. All procedures were performed with transoesophageal echocardiography monitoring. We used two AneuRx and nine Medtronic Talent or Valiant stent grafts.

RESULTS

All patients survived their traumatic isthmic rupture. In nine patients, stent-graft deployment was successful. One patient experienced a distal migration needing a laparotomy and deployment of an additional new thoracic stent graft. The mean intensive care unit stay was 48 hr (range 24-168). The mean hospital stay was 11 days (range 8-43). All patients were controlled clinically and by contrast computed tomography (CT) according to the EUROSTAR protocol. There were no endoleaks, stent graft-related complications, or late deaths during a mean follow-up of 49 months. The control CT showed a lack of apposition of the proximal part of the stent graft at the inner curve of the aortic arch in three patients.

CONCLUSION

The midterm results of endovascular treatment of acute traumatic aortic isthmic rupture are encouraging and compare favorably to the surgical approach. Late follow-up is required to exclude possible stent-graft complications, especially in young patients with angulated aortic arches.

Therapeutic hypertension: principles and methods

The aspects of cardiovascular physiology important for the safe and effective implementation and titration of hypertensive therapy among neurosurgical patients with neurological or neurosurgical illness/injury are reviewed. Therapeutic hypertension may be an appropriate treatment for some neurological or neurosurgical conditions, e.g., vasospasm or support of cerebral perfusion pressure. Initiation and maintenance of hypertension should be done safely to avoid complications and/or undesired side effects. Accurate measurement of the arterial and central vascular pressures, the limitations of those methods, and alternative estimates of intravascular volume are reviewed. Hypertensive therapy is accomplished by modifying cardiac output and systemic vascular resistance, the principal physiological determinants of blood pressure. The goals of hypertensive therapy can be achieved by proper evaluation and manipulation of the four components of cardiac output, preload, afterload, heart rate and contractility. Measurement or calculation of estimates of these parameters is important in the selection of proper medications or supplemental fluid administration.

Monitoring neurologic patients in intensive care

The brain is sensitive to changes in substrate delivery. In neurologically critically ill patients (e.g., those with head injury, subarachnoid hemorrhage, or stroke), interruption of this supply causes ischemic brain damage and thus impairs the outcome. To prevent, detect, and treat these ischemic events as soon as possible, the cerebral blood flow is continuously monitored, its coupling or not with the consumption of oxygen and so forth, and the detected derangements of normal physiology. Intracranial pressure and cerebral perfusion pressure are two parameters that often reflect ischemic events, and thus it is mandatory to continuously measure them. To better assess cerebral hemodynamics, jugular bulb oxymetry and brain pressure tissue oxygen monitoring are two neuromonitoring techniques that allow for a better understanding of the balance between oxygen supply and consumption, and therefore are useful in directing therapy. Transcranial Doppler ultrasonography is a noninvasive technique with the same purpose but with less clinical relevance. The new neuromonitoring technique, microdialysis, is useful for understanding the mechanisms involved in brain ischemia. However, it is clear that the physician who interprets the measurements given by devices and the clinical data (e.g., temperature, glycemia) is still the cornerstone in the management of neurologically critically ill patients.

Intracranial pressure and surgical decompression for traumatic brain injury: biological rationale and protocol for a randomized clinical trial

Commonly, severe traumatic brain injury (TBI) patients undergo amputation of contused brain; the rationale being that edema in presumed unsalvageable cerebrum increases intracranial pressure (ICP). Neuro-critical care expends great effort to control ICP and prevent secondary injury. Non-randomized investigations have employed hemicraniectomy with duraplasty after developing refractory ICP. We undertook a randomized pilot of hemicraniectomy with duraplasty as the initial surgery for severe TBI patients. Goals included reduced ICP therapeutic intensity and return to the operating room, and improved neurological outcome. Upon hospital presentation, the study was to randomize 92 patients with midline shift greater than the size of a surgically removable hematoma. One group was to receive standardized hemicraniectomy and duraplasty; the other would undergo 'traditional' craniotomy (with brain amputation at the neurosurgeon's discretion). A standardized medical protocol followed. The six-month Glasgow Outcome Scale was the primary outcome, with secondary measures including quality of life one year after TBI, duration and frequency of elevated ICP, intensive care unit (ICU) therapeutic intensity, operating room return, and ICU and hospital lengths-of-stay. This article presents the biological rationale and the evidence-based standardized protocols of the study and its outcome measures. The study has stopped and a phase III outcome trial is being organized.