Symptoms and Stages of Subarachnoid Hemorrhage: What You Need to Know
Subarachnoid hemorrhage (SAH) is a life-threatening type of stroke caused by bleeding into the space surrounding the brain. This condition typically progresses through four distinct phases, each with unique clinical manifestations. Understanding these stages is crucial for timely diagnosis and effective treatment, as symptoms can rapidly evolve and lead to severe neurological complications.
Phase 1: Acute Bleeding Stage
During the initial bleeding phase, symptoms usually appear suddenly and peak within the first 24 hours, although they may develop over a period of up to two weeks—or in rare cases, even a month. The hallmark of this stage is a sudden, intense headache often described as "the worst headache of my life." This is frequently accompanied by nausea, vomiting, and rapid changes in mental status ranging from confusion to loss of consciousness.
Neurological deficits can emerge quickly, including new-onset speech difficulties (aphasia), sudden weakness on one side of the body (hemiparesis), or seizures. These signs indicate increased intracranial pressure and potential damage to critical brain areas. Diagnosis at this stage relies heavily on non-contrast CT scans, which are highly sensitive for detecting fresh blood in the subarachnoid space. When imaging results are inconclusive, a lumbar puncture may be performed to analyze cerebrospinal fluid for the presence of xanthochromia—a yellowish discoloration indicating prior bleeding.
Phase 2: Cerebral Vasospasm Period
One of the most dangerous complications following SAH occurs 3 to 14 days after the initial bleed—cerebral vasospasm. During this phase, blood vessels in the brain constrict abnormally, reducing blood flow and potentially causing delayed cerebral ischemia or secondary strokes.
Key Signs of Vasospasm Include:
- Worsening levels of consciousness (e.g., lethargy, stupor)
- Focal neurological impairments such as paralysis or language deficits
- Cognitive decline or disorientation
The severity of symptoms often correlates with the location of the ruptured aneurysm. For instance, if the aneurysm is near motor or language centers, patients may experience more pronounced hemiplegia or aphasia. Monitoring with transcranial Doppler ultrasound and prompt intervention with calcium channel blockers like nimodipine are essential to prevent permanent brain injury.
Phase 3: Hydrocephalus Development
As blood products accumulate in the cerebrospinal fluid pathways, they can obstruct normal fluid circulation, leading to hydrocephalus—either acute or chronic. This phase may manifest days to weeks after the initial hemorrhage.
In mild cases, patients may exhibit subtle signs such as excessive drowsiness, slowed physical movements, reduced cognitive processing speed, and memory lapses. However, in more severe instances, the condition progresses to include significant cognitive deterioration, gait instability (often resembling normal pressure hydrocephalus), and urinary or fecal incontinence due to frontal lobe dysfunction.
Additional systemic effects may also occur, including autonomic dysregulation—such as fluctuations in catecholamine levels and sympathetic nervous system overactivity—which can contribute to cardiac arrhythmias or pulmonary complications. In such cases, interventions like ventriculostomy or shunt placement may be necessary to relieve pressure and restore CSF dynamics.
Phase 4: Recovery and Long-Term Outcomes
Following the acute and subacute phases, patients enter a prolonged recovery period that varies widely in duration and outcome. Neurorehabilitation plays a vital role in improving functional independence, addressing both physical and cognitive challenges.
Many survivors face long-term issues such as chronic headaches, mood disorders (including depression and anxiety), fatigue, and post-traumatic stress related to the traumatic onset of symptoms. Ongoing monitoring and multidisciplinary care—including neurology, psychology, physical therapy, and occupational therapy—are key components of successful rehabilitation.
Early recognition of symptoms across all four phases significantly improves prognosis. Public awareness and rapid access to specialized stroke care can make a critical difference in survival and quality of life after subarachnoid hemorrhage.