ICP and Cerebral perfusion pressure
- Keep ICP < 20 mmHg
- Maintain CPP:
| < 2 years | > 45-50 mmHg |
| 2-10 years | > 50-60 mmHg |
| 10-16 years | > 60-65 mmHg |
| > 16 years (adult) | > 70 mmHg |
Indications of ICP monitoring: These are suggestions only
- Severe TBI GCS < 8 with abnormal admission head CT (haematoma, contusion, cerebral oedema and/or compressed brain cisterns).
- Severe TBI GCS < 8 with normal admission head CT if two of the following features
- motor posturing
- systemic hypotension
- certain patients in whom serial neurological examination is precluded by sedation, NMB or anaesthesia.A physician may choose to monitor ICP in certain patients in whom serial neurological examination is precluded by sedation, NMB or anaesthesia.
- conscious patients with traumatic mass lesions suggestive of a risk of neurological deterioration (diffuse cerebral oedema or temporal lobe contusion on CT) may be monitored based on the opinion of the treating physician.
Maintenance of Normal CPP
Cerebral perfusion pressure = Mean Arterial Pressure - ICP
- CPP should be corrected whenCPP < the set age appropriate number for 5 min
- CPP < 10 mmHG below the set age appropriate number for any length of time
Give volume if low CVP or clinically indicated
Start on noradrenaline infusion
Treating raised ICP
Is there an easily correctable or transient cause?
- Hypercabia
- Hypoxia
- Hyperthermia
- Inadequate sedation/ analgesia
- Suctioning
These should be excluded and corrected before proceeding with further treatment.
Management of Increased ICP
- Consider repeat head CT to rule out space occupying lesion.
- Add neuromuscular blocking agent if not already used.
- Mannitol 0.25 g/kg IV (20%) over 20min. repeat to max 0.5 gm/kg q 6hr as needed. Hold if measured serum osmolality is > 320 mosm/L.
- Give 10 ml /kg of crystalloids ( 0.9% NaCl or Hartman) concomitant with mannitol.
- 2.9 % saline infusion 0.1 to 1 ml/kg/hr as a sliding scale. The minimum needed to maintain ICP < 20 mmHg should be used.
- Rapid changes in serum sodium should be avoided (< 10 mmol/L/day)
- Thiopentone therapy
- bolus dose of 3-5 mg/kg
- then IVI maintenance to maintain ICP, or burst supression on EEG (typically 1 - 5 mg/kg/hr).
- Carefull BP monitoring and cardiac output during Thiopentone infusion.
- Should aim to wean thiopentone once ICP controlled for 24 hours.
This is intended as a guide only. In some cases, it may be appropriate to tolerate higher ICP and maintain appropriate CPP rather than starting on thiopentone.
General Managment:
- Head of bed elevated 30 degrees and head in midline
- ABGs, U&E, and osmolality 6 hourly, or more frequent, as long as cerebral oedema and ICP are been treated.
- Aim to keep PaCO2 between 4.5- 5 kPa (33- 37 mmHg) on ABG
- Ranitidine IV 1 mg/kg 8 hourly until feed is established
- Early enteral feed
- TED stocking if age appropriate size is available
- Allow patient to re-warm passively if patient is hypothermic on admission to PICU.
- Maintain core temperature between 36.5 and 37 degrees C.
- Ensure a loading dose of phenytoin (20 mg/kg IV) has been given then 2 mg/kg (max 100mg) IV q 6hour after discussion with the PICU consultant in charge.
Fluid Management
- Use 0.9% saline for maintenance regardless of age or serum sodium.
- If hypoglycemic ( SG < 3.5 mmol/L) then change to 5% dextrose/ 0.9% saline
- Fluid balance in the first 72 hours may be maintained positive to keep appropriate CPP.
- There are some evidence to suggest that patient with higher serum sodium concentration has lower ICP, therfore serum soduim should be maintained above 140 mml/l during active ICP management.
- This could be achieved by either adding Na to NG feed if patient on full feed or 2.9 % saline infusion over 1 hour. (140-Na x 0.6x wt kg = mmol of Na. 1 ml 2.9% saline = 0.5 mmol of Na).
Suctioning
- Ensure adequate sedation and analgesia
- 100% O2 for 5 min prior to suctioning
- Give Fentanyl 2 micrograms/kg IV prior to suctioning
- If ICP> 20 mmHg for >5 min. or > 25 mmHg for any length of time despite the previous measures.
- Give Intra Tracheal Lignocaine 1% 0.15ml/kg prior to suctioning.
- If ICP> 20 mmHg for >5 min or > 25 mmHg for any length of time due to coughing with inter tracheal Lignocaine and /or suctioning then consider short acting neuromuscular blocker prior to each suctioning.