Glasgow look ups Flashcards
MOA of phenylephrine
alpha 1 agonist
causing vasoconstriction and increases in vascular resistance and increase in blood pressure
frontal nasal duct location
opens into the anterior part of the middle meatus or directly into the anterior end of the infundibulum
frontal sinus obliteration
Fractures of the floor of the sinus that involve the frontal recess and interfere with the drainage apparatus may render the sinus non functional. In this situation, frontal sinus obliteration may be required. This involves exposure of the entire sinus, fastidious removal of all sinus mucosa and obliteration of the sinus cavity with autologous tissue.
list of autologous materials for sinus obliteration
fascica (usually the choice) , abdominal fat, muscle, pericramium, bone
allograft
a tissue graft from a donor of same species as the recipient but not genetically identical vs autograft = tissue from own body.
allograft = human donor
xenograft
tissue from one species to another
porcine -
bovine -
equine etc
sinus obliteration
disruption of greater than 25% of the posterior table should be considered for cranialization. This involves exposure of the entire sinus, meticulous removal of all sinus mucosa, and removal of the posterior table bone. The anterior table bone is replaced to reconstitute the forehead contour.
Important: Complete removal of the posterior wall and obstruction of the sinus outflow tract is essential to create a “safe sinus”.
mydriasis is performed through what muscle / nerve
stimulation of alpha 1 receprots of iris dilator muscle
why would anesthesiologist be worried about mydriasis in patient?
impaired venous return from the head and neck
intracranial mass lesion
intracranial hemorrhage
outflow in maxillary sinus
cilia move mucus towards sinus ostium (O)
then passes vis the infundibulum (I)
next to the hiatus semilunaris into the
middle meatus
drainage of the frontal sinus
drains via a small outflow tract into the ethmoid sinus / nasal cavity
outflow tract is hour-glass shaped with
it communicates with the nasal cavity through the frontonasal duct (also known as the frontal recess), which opens into the middle meatus or the ethmoidal infundibulum
frontal recess involvment with fracture?
a frontal recess injury involves the FLOOR of the frontal sinus and the outflow tract
anterior, posterior, medial, and lateral walls of frontal recess
anterior = posterior wall of nasi air cell
posterior =ethmoid bulla
medial=middle turbinate
lateral = orbit
indications for ORIF of frontal sinus
displaced fractures of anterior table WITHOUT involvment of nasofrontal recess
frontal sinus obliteration / ablation
This entails the removal of all sinus mucosa, occlusion of the nasofrontal duct, and filling the sinus cavity with bone grafts or other materials.
Hydroxyapatite, pericranial flap obliteration, adipose tissue, calcium phosphate, and glass ionomer can also be used as grafting material.
A potential complication of this procedure is a mucocele secondary to incomplete removal of the mucosa during obliteration. If left untreated, mucocele growth can cause further bony destruction.
what mediates the mydriasis? - which nerve?
long ciliary nerve - which is sympathetic –
what happens with increased intracranial pressure? related to the eye?
rise in ICP can lead to pupil being dilated and unresponsive
unknown cause of mydriasis concerncing for
problem within the brain head injury, tumor, stroke
pupillary dilation pathway where is 1st 2nd and 3rd order neuron DETAILS
1st = CNS (hypothalamus)
2nd, 3rd = PNS
2nd = preganlgionic that go and synapse at superior ganglion
3rd order = postganglionic fibers that are in close proximity to the internal carotid artery
JOIN with nasocilliary nerve which is a branch of the trigemnial nerve (opthalmic) then travel through long ciliary nerves to the dilator pupillae
compression of occulomotor nerve?
usually will constrict the pupil - but if it it cannot perform this then we have dilation
pupil at baseline / when dead
dilated bc do not have innervation of the parasymptathetic occulomotore nerve
landmark for gillies approach
2.5 cm superior and anterior to helix of ear3
key features / classification of nasal fractures
open / closed
deviated / non deviated
comminuted
4 main tx options for nasal fx
observe and treat w/ meds (NSAIDS/ antinflammatory)
manual manipulation and reduction
forceps reductions
open septorhinoplasty technique
medial canthal tendon insertion ?
superficial portion?
deep portion?
superficial - frontal process of maxilla
deep - posterior lacrimal crest and is known as horners muscle / par lacrimalis
two external diagnostic tests to determine integrity og medial canthal tendon and how perform?
Bowstrings test - pull eyelid laterally while palpating MCT to detect movement of fracture segments
furnas test - grasp skin overlying MCT with forceps. lack of creasing or resistance indicated underlying fracture likely
