Setting: ED
CC: “My head hurt real bad, then I passed out.”
VS: BP: 154/94 mm Hg; P: 110 beats/minute; T: 100.8°F; R: 18 breaths/minute
HPI: A 34-year-old woman with no significant past medical history is brought by ambulance to the ED after passing out in the nave of Le Parker Meridien hotel. She was sitting at lunch with her mother and suddenly developed an excruciating headache. She woke up a few minutes later while being loaded into the ambulance.
Medications: none
PE:
General: uncomfortable, shielding her eyes
HEENT: photophobia and neck stiffness present
Neurological: no focal deficits
Why is this not meningitis?
• Sudden in onset
• Loss of consciousness
Initial Orders:
• Head CT
What is “special” about the CT to order?
a. Use contrast.
b. Order thin cuts through the base of the brain.
c. Wait 24 to 48 hours for greater sensitivity.
Answer b. Order thin cuts through the base of the brain.
Because blood is heavier than cerebrospinal fluid (CSF), you should do thin cuts through the base of the brain to detect small bleeds. The blood will have settled to the base of the brain by gravity. Contrast is used to detect abscess and neoplasia. Waiting markedly decreases the sensitivity of the CT for blood.
Any adult admission to hospital should have:
• CBC
• Basic metabolic panel (CHEM-7)
• ECG
• Chest x-ray
• Urinalysis (UA)
You will not lose points by ordering these tests on CCS and you may “trip” over the diagnosis by accident.
The maximum sensitivity of a CT is within the first 12 hours after the bleed.
Advance the clock just enough to get the results of the CT scan. You cannot initiate therapy until you know if there is blood.
Report:
Head CT: subarachnoid hemorrhage (SAH) diffusely surrounding brain (Figure 4-2)
Figure 4-2. Classic appearance of a large subarachnoid hemorrhage. Notice the hemorrhage pattern fills the cerebrospinal fluid spaces at the base of the brain and around the brainstem. (Reproduced with permission from Doherty GM. Current Diagnosis & Treatment: Surgery, 13th ed. New York: McGraw-Hill; 2010.)
If the CT were negative, what test would have been next?
a. Lumbar puncture (LP)
b. MRI
c. Digital subtraction angiogram
Answer a. Lumbar puncture (LP)
The sensitivity of CT in SAH is 92% to 95% on the first day and approaches 100% in the first 6 to 12 hours. MRI is not as useful to detect blood. The key points on LP in SAH are:
• There is a high opening pressure.
• There is no change in cell count from tube 1 to tube 4.
• Xanthochromia starts in 2 hours.
• Spectrophotometry detects bilirubin 12 hours after a bleed.
The patient’s BP is 146/92 mm Hg. She is awake and uncomfortable, shading her eyes.
What should you do about the patient’s elevated BP?
a. No therapy is indicated.
b. Give IV fluids and phenylephrine to raise it further.
c. Give labetalol to lower it further.
Answer a. No therapy is indicated.
Modest hypertension probably helps cerebral perfusion in SAH. It is clear that attempting to decrease BP to a low pressure, for example, <120/80 mm Hg, in this patient is likely dangerous. This would represent a >25% drop from the original BP of 154/94 mm Hg and might impair cerebral perfusion. There is no clear benefit to using fluids and phenylephrine or dopamine to raise BP more.
What is the mechanism of loss of consciousness in SAH?
a. Increased intracranial pressure suddenly decreases CNS perfusion.
b. Vasospasm.
c. Potassium alteration.
Answer a. Increased intracranial pressure suddenly decreases CNS perfusion.
Bleeding into the brain increases the intracranial pressure and decreases the ability of blood to get into the brain. This is why hypotension is so dangerous after an SAH. Therapeutic hypertension with fluids and pressors (phenylephrine or dopamine) is not clearly beneficial. Vasospasm occurs after SAH in response to the bleeding. Vasospasm is not the cause of the loss of consciousness. It is a reaction to it.
Move the patient to the ICU.
Consult neurosurgery.
Repeat vital signs every 2 hours, especially watching for extremes of BP.
Which is the best method to find the location of the bleed?
a. Digital subtraction angiography (DSA)
b. MRI
c. Repeat CT
Answer a. Digital subtraction angiography (DSA)
DSA is the best method to determine the location of the aneurysm. You need to find the site of the lesion and repair it as soon as possible. Do not delay the DSA. The greatest chance of rebleeding is on the first day of the bleed. Half of people who rebleed will die.
Get a move on! Get the DSA.
What is the most common cause of SAH?
a. Sudden hypertension
b. Spontaneous rupture of a saccular aneurysm of the circle of Willis
c. Trauma
d. Vasculitis
Answer b. Spontaneous rupture of a saccular aneurysm of the circle of Willis
As much as 2% to 5% of the population has saccular aneurysm of the circle of Willis at autopsy. Almost all remain unruptured at the time of death. It is not clear why some rupture and others do not. Although cigarette use and hypertension are associated with rupture, this is not a direct temporal relationship such as “I was fine until I smoked that cigarette.”
The DSA shows the location of the aneurysm to be the anterior communicating artery. The patient’s BP is 142/90 mm Hg.
What is the best way to fix it?
a. Craniotomy and open repair
b. Endovascular coiling and embolization with platinum wire
c. Laparoscopy
d. Nimodipine
Answer b. Endovascular coiling and embolization with platinum wire
Endovascular coiling clots off the site of the bleed and does not require craniotomy. Laparoscopy is for the pelvis and abdomen. Nimodipine is used to prevent subsequent stroke but does not fix the site of the aneurysm.
Platinum wire
• Does not oxidize
• Is biologically inert
Nimodipine
• Is a calcium channel blocker
• Prevents vasospasm
• Decreases risk of “downstream” stroke
• Does not prevent rebleeding
Once the DSA shows the location of the aneurysm, order the endovascular repair procedure with coiling and embolization. If this is a multiple choice question and the stem says “Coiling is not available at your hospital,” the answer is “Transfer to a hospital that does coiling/embolization.” Do not alter the proper care of a patient around the logistics at your hospital. Move hospitals rather than do a procedure that is not ideal.
Get patients what they need.
Never do an inadequate procedure because it is not available at your institution.
Alter logistics to get right care.
Do not alter right care around logistics.
The patient undergoes the platinum wire coiling procedure and the site of the aneurismal bleed is repaired. Nimodipine is ordered and the patient’s BP is 134/88 mm Hg.
The following treatments are not clearly beneficial and we do not recommend their routine use:
Hypothermia
Antiepileptic drugs
Steroids
Statins