Resuscitating the injured brain

Resuscitating the Injured

Brain“It’s the little things that matter”

By Kane Guthrie

Learning Points

How to resuscitate the injured brain.

A case.

Understanding of primary Vs secondary injury.

Learn about the little things that make a difference in TBI.

Traumatic Brain Injury

Leading cause of death in children and young adults!

Main cause of lifelong disability after trauma!

Optimal early Mx can have profound effect on their prognosis!

What we do downstairs can make the difference upstairs!

Case Study

27 male 1x punch to head, LOC,

hit ground. GCS 5/15 Intubated and sedated. Taken to the doughnut.

Now what?

The PathO!

Primary

Physical damage to parenchyma.

Occurs during traumatic event.

Results in shearing/compression of brain tissue.

Not Reversible!

Secondary

Complex process. Results from primary

injury and acute disorder that occur from this.

1. Hypotension2. Hypoxia3. Hypo/Hypercarbia

Preventable and reversible!

The Types

Primary

Extra-axial: Epidural haematoma Subdural haematoma SAH Intraventricular

HaematomaIntra-axial: Axonal injury Cortical contusion ICH

Secondary

Acute: Diffuse cerebral

swelling Brain herniation Infarction InfectionChronic: Hydrocephalus CSF leak

The @ risk groups!

The Elderly

Infants

The anticoagulated

Chronic alcoholics

The other Lethal Triad!

or

or

Our Goals in ED

Resuscitate & assess for other injuries.

Prevent & treat raised ICP & secondary brain insults.

Avoid hypoxia & hypotension.

Preservation of CPP.

Optimisation of cerebral oxygenation.

The Big Things

Focus on correcting/preventing secondary brain insults:

Avoid Hypoxia and Hypotension

Prevent ∧ICP & impaired cerebral perfusion

Reverse anticoagulation

Protect and secure airway

Rule out C-spine injuries

The Algorithm

The Little Things!!

Once the big things are done:

Its time to optimise:

Pt Position

Cervical collar

Temperature

BP

Seizure prophylaxis

Glucose

Patient Position

Elevate the head of bed to 30-45°C.

Decreases ICP by: Displacing the CSF. Increasing venous outflow.

Also decrease risk of VAP!

Use reverse trendelenburg if cervical spine an issue!

Trendelenburg Position.

Time honored tradition for the hypotensive Pt.

More harm than good.

May give transient rise in BP.

But:

Raise’s ICP through venous congestion.

Worsen hypotension pushing abdo organs in thorax decrease venous return to heat.

Alter ventilation & perfusion.

Securing the Tube

Tape Vs Ties Ties can constrict

venous return and raise ICP.

Best to avoid!

Cervical Collar

AKA the “BRAIN TOURNIQUET”

Removal ∨ ICP by 2-5 mmHg.

If unable to remove – loosen enough so it aids venous return!

Temperature Mx

Therapeutic hypothermia – no good evidence yet. (POLAR study just starting)

Fever is bad : ∧ oxygen consumption ∧ cerebral metabolic rate.

We SHOULD focus on therapeutic normothermia!

Monitor closely and keep temp <37°C.

Blood Pressure Mx

Abnormal BP is common!

Hypotension = detrimental & needs to be treated aggressively – maintain CPP.

Hypertension can occur due to raised ICP, medical condition, or pain & anxiety.

Use sedative/analgesia first line if intubated.

Rarely use short acting antiHT and dose gingerly to avoid hypotension and ∨CPP.

(Archives of Surg 2001:136;1118-1123)

Cerebral Perfusion Pressure

CPP = MAP – ICP.

Elevated ICP - leads to loss of CPP – leading irreversible brain damage.

Difficult to measure ICP & CPP in the ED.

Focus on avoiding hypoxia and hypotension.

Aim for Spo2>90 & BP> 90 with target MAP >70mmHg gives you an estimate of CPP of around 50-70mmHg.

Seizure Prophylaxis

Limited evidence to support practice!

However:

The injured brain that's seizing isn’t a good sign.

Give prophylaxis:

Phenytoin

Levetiracetam (Keppra).

Glucose Mx

Controversial topic in critical care!

Hyperglycaemia in TBI generally = poor neuro function.

Hypoglycaemia is bad – brain obligate glucose consumer.

Studies show intensive insulin therapy - more hypo’s & ?increase mortality.

Take home point:

Treat Pt’s with marked hyperglycaemia but avoid hypoglycaemia. Aim for BSL 8-12mm0L

In Summary

1. Avoid hypotension & hypoxia at all cost!

2. Sit them up decreases ICP & VAP!

3. Keep a close eye on the BP, BSL & Temp!

4. Try and clear the neck early and tape the tube!

Remember

What YOU do matters!

Mel Herbert.

But!