Random Flashcards
What antibodies are seen in Lambert Eaton syndrome?
Anti voltage gated calcium channel antibodies
What is anderson-Tawil syndrome?
Long QT syndrome and periodic paralysis due to mutations in skeletal muscle ion channels.
What condition would you get anti-Gq1B antibodies?
Miller Fisher variant of GBS.
What is the artery of Percheron?
Anatomical variant, unpaired artery arising from P1 supplying bilateral medial thalami
What are the features of a lacunar stroke?
Motor symptoms only
What is CADASIL?
Genetic condition caused by mutation in NOTCH3 gene on Chromosome 19. (Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencepholopathy )
Predisposed to TIAs and strokes, often have history of migraines
What are the 6 layers of the cerebral cortex?
Molecular, External Granular, External pyramidal, Internal granular, internal pyramidal, fusiform
Which layers of the LGN do the nasal fibres go to?
1,4 and 6 (temporal is 2,3 and 5)
What is thalamic pain syndrome?
Posterior medial thalamic infarct resulting in hemisensory loss which then becomes neuropathic pain
Which cerebellar peduncle only has efferents?
Middle cerebral peduncle
Verocay bodies are required histologically to give what diagnosis?
Schwannomas
What percentage of cardiac output is taken by the brain?
15-17% (750ml/min in adults)
Describe the parts of the ICP wave
The first arterial wave is the percussion wave, which reflects the ejection of blood from the heart transmitted through the choroid plexus in the ventricles. The second wave is the tidal wave, which reflects brain compliance; and finally, the third wave is the dicrotic wave that reflects aortic valve closure
Under physiologic conditions, the percussion wave is the tallest, with the tidal and dicrotic waves having progressively smaller amplitudes.
alpha-2 adrenergic stimulation, free calcium ions, thromboxane A2, and endothilin have what effect on blood vessels?
Constrict
What percentage of oxygen does the brain use? What about glucose?
20% Oxygen
25% glucose
What CBF will cause infarction at 2-3 hours of sustained exposure?
In the penumbra (10-17ml/100g/min)
What did the IHAST2 trial show?
The role of mild hypothermia in neurovascular surgery is less clear after Intraoperative Hypothermia After Aneurysm Surgery Trial (IHAST2), an international double-blind trial in which 1001 WFNS1-3 aneurysmal SAH patients undergoing aneurysm clipping were subjected to mild hypothermia (33 °C at clip placement) versus normothermia (36.5 °C) with no difference in outcome.
What did the Eurotherm trial show?
From 387 patients, the data committee found a statistically significant increase in the odds of an unfavorable outcome and death at 6 months in the group allocated to therapeutic hypothermia, hence it was discontinued due to futility.
What are the criticisms of Eurotherm?
very early use (i.e. tier 2) of hypothermia with high potential variability of subsequent management, inclusion criteria any head injury in previous 10 days, only ICP used as a guide (not CPP).
What kind of patient is ASA 6?
Organ harvesting!
What is the treatment for malignant hyperthermia?
Dantrolene
What is the Bohr effect?
Shift of oxygen-Hb dissociation curve to the right.
This change is caused by increased body temperature, acidosis, chronic hypoxia (increased 2,3-BPG) and hypercapnia.
What is the circulating blood volume of a neonate?
80-90ml/kg
What FVC is in keeping with respiratory failure?
less than 15-20ml/kg
Criteria for brainstem testing?
- patient’s condition is due to irreversible brain damage of known etiology
- Potentially reversible causes of coma have been excluded
- There is no evidence that the patient’s state is due to depressant drugs
- Primary hypothermia as the cause of unconsciousness has been excluded
- Potentially reversible circulatory, metabolic and endocrine disturbances have been excluded as the cause of continued unconsciousness
- Potentially reversible causes of apnea have been excluded and there is intact neuromuscular transmission
Commonest location for venous sinus thrombosis?
Superior saggital sinus 50%
