Intern Report Case 5.1

Case Presentation by Dr. Meredith Hill

50 y/o male brought in by EMS with signs of head trauma.  According to EMS patient had been drinking and was assaulted.  EMS reports that the patient was stuck in the head multiple times with an unknown object.  On presentation the patient is combative, uncooperative and unable to provide any coherent history.

Physical exam:

VS: BP 200/100 HR: 106 RR: 18

Constitutional: Patient is c-collared and back-boarded, disoriented and combative with staff.

HEENT: Patient has significant trauma to the head and face, with a 5 cm laceration noted on the patient’s occiput.  Pupils 4mm, equally round and reactive to light. Right TM is unremarkable, clear fluid is noted behind the left TM.  Clear fluid is noted in the patient’s nares bilaterally.

Neuro: Patient is opening eyes spontaneously.  The patient is moving all four extremities spontaneously and with good strength.  Patient is not answering question appropriately and is not co-operating with examination.

The rest of Physical exam is WNL.

QUESTIONS

1.  The following image is of the patient’s left ear, what injury is this consistent with?

A.  A skull fracture with a  fracture line communicating with the mastoid air cells, resulting in accumulation of blood in the cutaneous tissue.

B.  A blow directly to the left ear causing bruising over the mastoid bone.

C.  A skull fracture where the fracture line communicates with the auditory canal, resulting in bleeding into the middle ear.

D.  A result of bleeding from a fracture site in the anterior portion of the skull base.

2.  You notice some clear fluid leaking from the patient’s nose.  You are concerned that this is CSF.  What bedside tests can you do to either confirm or refute that this is CSF?

A.  Take a drop of the fluid and place it on filter paper and look for  double ring of clear fluid and blood.

B.  Do an accu check on the fluid and if it is greater than 90 this confirms that it is CSF.

C.  Send a sample to the lab for beta2 transferrin testing to confirm a CSF ottorhea.

D.  Smell a sample of the fluid on your gloove to see if it smells sweet.

3.  The CT of the patient above confirms a basilar skull fracture with a CSF leak.  What is the next best treatment for this patient?

A.  Administer prophylactic broad-spectrum antibiotics and discharge the patient.

B.  Administer prophylactic broad-spectrum antibiotics and admit

C.  No prophylactic antibiotics should be given and patient may be discharges if no other injuries exist

D.  Admit for observation and discuss the patient with neurosurgery regarding starting prophylactic antibiotics

Please submit your answers to the questions in the “leave a reply” box or click on the“comments” link.  Your submission will not immediately post.  Thank you for participating in Receiving’s: Intern Report.

 

Answers

Question 1 – A

Question 2 – A

Questions 3 – D

Basilar skull fracture

In essence, a basilar fracture is a linear fracture at the base of the skull. It is usually associated with a dural tear and is found at specific points on the skull base. Basilar skull fractures represent 19-21% of all skull fractures

Temporal fracture

Temporal bone fracture is encountered in 75% of all skull base fractures. The 3 subtypes of temporal fractures are longitudinal, transverse, and mixed.

Transverse temporal bone fracture (courtesy of Adam Flanders, MD, Thomas Jefferson University, Philadelphia, Pennsylvania)

Longitudinal temporal bone fracture (courtesy of Adam Flanders, MD, Thomas Jefferson University, Philadelphia, Pennsylvania

Longitudinal fracture occurs in the temporoparietal region and involves the squamous portion of the temporal bone, the superior wall of the external auditory canal, and the tegmen tympani. These fractures may run either anterior or posterior to the cochlea and labyrinthine capsule, ending in the middle cranial fossa near the foramen spinosum or in the mastoid air cells, respectively. Longitudinal fracture is the most common of the 3 subtypes (70-90%).

Transverse fractures begin at the foramen magnum and extend through the cochlea and labyrinth, ending in the middle cranial fossa (5-30%).

Mixed fractures have elements of both longitudinal and transverse fractures.

Yet another classification system of temporal bone fractures has been proposed. This system divides temporal bone fractures into petrous and nonpetrous fractures; the latter includes fractures that involve mastoid air cells. These fractures do not present with cranial nerve deficits.

Occipital condylar fracture

Occipital condylar fracture results from a high-energy blunt trauma with axial compression, lateral bending, or rotational injury to the alar ligament. These fractures are subdivided into 3 types based on the morphology and mechanism of injury. An alternative classification divides these fractures into displaced and stable, ie, with and without ligamentous injury.

Type I fracture is secondary to axial compression resulting in comminution of the occipital condyle. This is a stable injury.

Type II fracture results from a direct blow, and, despite being a more extensive basioccipital fracture, type II fracture is classified as stable because of the preserved alar ligament and tectorial membrane.

Type III fracture is an avulsion injury as a result of forced rotation and lateral bending. This is potentially an unstable fracture.

Clivus fractures

Fractures of the clivus are described as a result of high-energy impact sustained in motor vehicle accidents. Longitudinal, transverse, and oblique types have been described in the literature. A longitudinal fracture carries the worst prognosis, especially when it involves the vertebrobasilar system. Cranial nerves VI and VII deficits are usually coined with this fracture type.

Signs and diagnosis

Patients with fractures of the petrous temporal bone present with CSF otorrhea and bruising over the mastoids, ie, Battle sign. Presentation with anterior cranial fossa fractures is with CSF rhinorrhea and bruising around the eyes, ie, “raccoon eyes.” Loss of consciousness and Glasgow Coma Score may vary depending on an associated intracranial pathologic condition.

Longitudinal temporal bone fractures result in ossicular chain disruption and conductive deafness of greater than 30 dB that lasts longer than 6-7 weeks. Temporary deafness that resolves in less than 3 weeks is due to hemotympanum and mucosal edema in the middle ear fossa. Facial palsy, nystagmus, and facial numbness are secondary to involvement of the VII, VI, and V cranial nerves, respectively. Transverse temporal bone fractures involve the VIII cranial nerve and the labyrinth, resulting in nystagmus, ataxia, and permanent neural hearing loss.

Occipital condylar fracture is a very rare and serious injury. Most of the patients with occipital condylar fracture, especially with type III, are in a coma and have other associated cervical spinal injuries. These patients may also present with other lower cranial nerve injuries and hemiplegia or quadriplegia.

Vernet syndrome or jugular foramen syndrome is involvement of the IX, X, and XI cranial nerves with the fracture. Patients present with difficulty in phonation and aspiration and ipsilateral motor paralysis of the vocal cord, soft palate (curtain sign), superior pharyngeal constrictor, sternocleidomastoid, and trapezius.

Collet-Sicard syndrome is occipital condylar fracture with IX, X, XI, and XII cranial nerve involvement.

CT showing left sphenoid sinus and an air-fluid level

CT scan: CT scan is the standard modality for aiding in the diagnosis of skull fractures. Helical CT scan is helpful in occipital condylar fractures, but 3-dimensional reconstruction usually is not necessary.  Be careful: fractures can be missed on CT. Always correlate clinically with mechanism of injury and physical exam.

Of  note, patients may have developed Battle sign later, but because the patient in our case presented immediately after his injury, this exam finding was not present.  It takes time for the communicating fracture to accumulate. Therefore, if Racoon and Battle sign are negative, it does not mean you can rule out a basilar skull fracture immediately.  Clinical correlation and the timeline of injury must be considered.  The clinical manifestations of basilar skull fracture may take 6 to 12 hours to fully develop

double-ring sign, comprises blood (inner ring) and CSF (outer ring).

Testing for the double ring sign: take a drop of the fluid and place on filter paper (can be a coffee filter) or a sheet and look for a halo sign. (In our case, a drop of the ottorhea was seen separating on the EMT paper sheets.)  The double “halo” seen when CSF hits filter paper may help to indicate that the pt has an open communicating basilar skull fracture but is not definitive.

Glucose testing of ottorhea: Testing the fluid for glucose level helps distinguish spinal fluid from nasal secretions, which are low in glucose  but contamination of the specimen with blood, serum, tears, or saliva may lead to a false-positive result. State what the glucose of csf from the nose or ear would be expected.

Beta 2 transferrin: This is not a bedside test. Testing for beta2 transferrin, a substance found only in CSF, may identify the substance with a greater degree of certainty. However, the test for beta2 transferrin may not be readily available and the result may not be returned for days to weeks. None of the listed confirmatory tests for CSF ottorhea should hold patient up from CT but can be quick adjunctive tests to help quickly care for a patient.

Management

Call neurosurgery.  Depending patient (if immunosupressed) prophylactic ABX can be started and manitol can laso be used for ICP control. However, these should not be sarted until consulting neurosurgery.

Misc.

The risk of infection is not high, even without routine antibiotics, especially with CSF rhinorrhea. Facial palsy and ossicular chain disruption associated with basilar fractures are discussed in the Clinical section. However, notably, facial palsy that starts with a 2- to 3-day delay is secondary to neurapraxia of the VII cranial nerve and is responsive to steroids, with a good prognosis. A complete and sudden onset of facial palsy at the time of fracture usually is secondary to nerve transection, with a poor prognosis.

Other cranial nerves also may be involved in basilar fractures. Fracture of the tip of the petrous temporal bone may involve the gasserian ganglion. An isolated VI cranial nerve injury is not a direct result of fracture, but it may be affected secondarily because of tension on the nerve. Lower cranial nerves (IX, X, XI, and XII) may be involved in occipital condylar fractures, as described earlier in Vernet and Collet-Sicard syndromes (vide supra). Sphenoid bone fracture may affect the III, IV, and VI cranial nerves and also may disrupt the internal carotid artery and potentially result in pseudoaneurysm formation and caroticocavernous fistula (if it involves venous structures). Carotid injury is suspected in cases in which the fracture runs through the carotid canal; in these instances, CT-angiography is recommended.

Signs and symptoms

Pearls

  1. The clinical manifestations of basilar skull fracture may take 6 to 12 hours to fully develop.
  2. Since plain films are unhelpful, there should be a low threshold for head CT in any patient with head trauma, loss of consciousness, change in mental status, severe headache, visual changes, or nausea or vomiting.
  3. The use of filter paper or a dextrose stick test to determine if CSF is present in rhinorrhea is not 100% reliable.
  4. Fracture of the temporal bone could result in temporary conductive hearing loss caused by disruption of the ossicular chain.

Sources:

Skull Fracture.http://emedicine.medscape.com/article/248108-overview.accessed%5B11/02/2011%5D

The Atlas of Emergency Medicine :Chapter 1. Head and Facial Trauma

2 Responses

  1. Case 5.1
    Q1. this is a battle sign

    Q2. C this test is the most sensitive and specific compared to the old way of figuring the amount of glucose and protein in the csf. Not sure what the turn around time is.

    Q3. simple linear fractures with low amount of leak could potentially be discharged. However, if this was an open fracture it would likely require antibiotics. If the csf leak continues the pt will likely need measures to decrease intracranial pressures…which may include a lumbat drain. Since it could involve these I believe the pt should be observed and discuss abx w the neurosurgeon.

  2. 1.
    2. I am assuming that this is the halo/ring sign. It is true that beta2 transferrin testing can confirm a CSF ottorhea, however this is a send out lab and therefore not very useful as a bedside test!
    3. From what I have read, no prophylactic antibiotics are administered, but this patent needs to be admitted as he has a head injury and is altered, either from the head injury, the alcohol, or both.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: