The Neurosurgical Society of Australasia maintains a set of recommendations for managing a deteriorating patient in remote and rural locations. Treatment guidelines are based on time to definitive care and have been adapted for use.
If considering the below, contact ARV to speak with a trauma service and neurosurgical specialist for advice. CLICK ON IMAGE TO ENLARGE
Each of the above recommendations will be discussed in the following section.
Assume brainstem herniation
Assume brainstem herniation in an unresponsive (comatose) patient with:
bilateral dilated unresponsive pupils or unilateral dilated unresponsive pupils and
abnormal extension (decerebrate posturing) or no motor response to painful stimuli
If signs of herniation
Hyperventilate at a rate of 20 breaths per minute, aim for an ETCO2 of 30 mmHg. Monitor the response with ETCO2 readings or ABG. Top of Page
Hyperventilation to a PaCO2 of 30 mmHg helps lower ICP by causing cerebral vasoconstriction and lowering cerebral blood flow. Prolonged hyperventilation may actually produce cerebral ischaemia and so it should be used in moderation and for as short a duration as possible. This therapy can be instituted by a doctor in situations where impending uncal herniation is present. Ideally, consultation via ARV with a trauma service and neurosurgeon prior to hyperventilation therapy is recommended.
Intravenous solutions that exert an osmotic effect, such as mannitol 20% and hypertonic saline solution (> 1.5%): have been the mainstay of treatment for many years. Cautious use of these therapies is advised and should only be considered as a rescue intervention when signs of herniation are present or rapid neurological deterioration is evident. There is little evidence at this stage to state which therapy has a better outcome in patients with severe TBI. The decision as to which treatment is used may reflect the availability of each and the preference of the specialist neurosurgeon.
Mannitol 20%: This should be administered at a dose of 0.25–1 g/kg given intravenously as a bolus over 20 minutes. Its effect will be exerted in around 20–40 minutes. Monitoring of fluid balance as well as renal function is important. Be aware that it can cause a precipitous drop in blood pressure once administered and the patient may require inotropic support to maintain a SBP > 110 mmHg.
Hypertonic saline: This may be used as an alternative to mannitol. Administer at a dose of 6–8 mL/Kg of 3% solution or 4 mL/Kg of 7.5% solution, given as a bolus. As above, close monitoring of output, serum sodium and blood pressure should be undertaken. Top of Page
Burr hole evacuation
Emergency burr hole craniotomy may be necessary where time to definitive care is prolonged. This procedure is especially important in a patient who is rapidly deteriorating and does not respond to non-surgical measures. The decision to conduct burr hole evacuation is based on:
estimated transfer time
clinical state – level of consciousness, pupillary size and light reflex
rate of deterioration
CT scan (if available) or x-ray of skull
level of surgical experience and range of neurosurgical equipment available at the regional hospital.