Subarachnoid Hemorrhage

Abstract

PURPOSE OF REVIEW Subarachnoid hemorrhage (SAH) remains an important cause of mortality and long-term morbidity. This article uses a case-based approach to guide readers through the fundamental epidemiology and pathogenesis of SAH, the approach to diagnosis and management, the results of clinical trials and evidence to date, prognostic considerations, controversies, recent developments, and future directions in SAH. RECENT FINDINGS Historically, management of SAH focused on prevention and treatment of subsequent cerebral vasospasm, which was thought to be the primary cause of delayed cerebral ischemia. Clinical and translational studies over the past decade, including several therapeutic phase 3 randomized clinical trials, suggest that the pathophysiology of SAH-associated brain injury is multiphasic and multifactorial beyond large vessel cerebral vasospasm. The quest to reduce SAH-associated brain injury and improve outcomes is shifting away from large vessel cerebral vasospasm to a new paradigm targeting multiple brain injury mechanisms, including early brain injury, delayed cerebral ischemia, microcirculatory dysfunction, spreading cortical depolarization, inflammation, and the brain-body interaction in vascular brain injury with critical illness. Despite multiple negative randomized clinical trials in search of potential therapeutic agents ameliorating the downstream effects after SAH, the overall outcome of SAH has improved over recent decades, likely related to improvements in interventional options for ruptured cerebral aneurysms and in critical care management. Emerging clinical evidence also suggests potential harmful impact of historic empiric treatments for SAH-associated vasospasm, such as prophylactic induction of hypertension, hypervolemia, and hemodilution (triple H therapy). With decreasing mortality, long-term SAH survivorship and efforts to reduce chronic morbidity and to improve quality of life and patient-centered outcome are growing areas of unmet need. Despite existing guidelines, significant variabilities in local and regional practices and in scientific terminologies have historically limited advancement in SAH care and therapeutic development. Large global collaborative efforts developed harmonized SAH common data elements in 2019, and studies are under way to examine how existing variabilities in SAH care impact long-term SAH outcomes. SUMMARY Although the overall incidence and mortality of SAH is decreasing with advances in preventive and acute care, SAH remains a major cause of long-term morbidity in survivors. Significant variabilities in care settings and empiric treatment protocols and inconsistent scientific terminologies have limited advancement in patient care and therapeutic clinical studies. Large consensus efforts are under way to introduce clinical guidelines and common data elements to advance therapeutic approaches and improve patient outcome.

Early management of patients with aneurysmal subarachnoid hemorrhage in a hospital with neurosurgical/neuroendovascular facilities: a consensus and clinical recommendations of the Italian Society of Anesthesia and Intensive Care (SIAARTI)—part 2

“…2 Close to the lower limit (80 mmHg) for patients without a history of arterial hypertension and close to the upper (100 mmHg) for patients with a history of arterial hypertension. 3 60 mg every 4 h for 21 days after bleeding (oral or nasogastric tube); intravenous nimodipine (2 mg/h) in case of feeding intolerance. Do not utilize in hemodynamically unstable SAH patients or withheld in case of a significant drop in arterial blood pressure.…”

“…Aneurysmal subarachnoid hemorrhage (SAH) is a complex and multifaceted pathology which plays out over days to weeks and which often requires prolonged intensive care unit (ICU) stay [1,2]. Initial care of aneurysmal SAH patients is aimed at stabilizing life-threatening conditions, particularly for comatose patients with impaired respiratory and hemodynamic function [1][2][3]. Despite early aggressive resuscitation and multidisciplinary ICU management have shown to be potentially associated with improved outcomes [4], the mortality remains high and the complication rate of these patients can be also related to factors occurring after initial stabilization and aneurysm treatment [5].…”

“…The management of SAH patients focuses on the anticipation, prevention, and management of these secondary complications and thus can be particularly challenging for the intensivist [3,7]. However, a high level of evidence is lacking even regarding the management of SAH in this phase.…”

Evaluating common medications utilized in aneurysmal subarachnoid hemorrhage and association with delayed cerebral ischemia

“…DCI can be caused by several factors, including cortical spreading depression (CSD) and cerebral vasospasm, and its occurrence is a major source of inpatient morbidity and mortality in SAH patients [3,4], and thus far the only widely used method to improve outcomes is administration of the calcium channel blocker nimodipine [3,4]. DCI occurs in approximately 30% of post-SAH patients, and its occurrence is predictive of poor SAH outcomes [4,5]. DCI has been associated with younger age and high score on the modi ed Fisher scale, however clear risk factors for DCI remain sparse [3,4].…”

“…DCI occurs in approximately 30% of post-SAH patients, and its occurrence is predictive of poor SAH outcomes [4,5]. DCI has been associated with younger age and high score on the modi ed Fisher scale, however clear risk factors for DCI remain sparse [3,4]. Although promising medical and interventional therapies are undergoing trials to prevent DCI [3], few studies have evaluated associations between DCI and commonly used analgesic and anti-seizure medication dosages already utilized in the management of many SAH patients [6][7][8][9][10][11][12].…”