Aneurysms bagaimana cara menangani ini.PPT

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1. Anesthesia for Intracranial
Aneurysm Surgery
Pekka O. Talke, MD

2. Aneurysms
•2-5 % population
•30K SAH/yr
•2/3 get to hospital
•1/3 in hospital severely disabled or dead
•Unruptured:1-2%/yr rupture
•Ruptured: 50% rerupture within 6 mo
•Urgent, not emergent cases

3. Surgeons
•Lawton

4. Anesthetic Goals
•Prevent aneurysm rupture (avoid hypertension)
•Decrease ICP (surgical exposure, retraction)
•Maintain CPP (>70 mmHg)
•Prevent cerebral ischemia from retraction
•Good operating conditions (NO movement, brain
relaxation for exposure)

5. Patients, preop
•Symptomatic/asymptomatic
•Ruptured (SAH grade, myocardial effects),
unruptured
•Possibly intubated
•Location and size of aneurysm
•Intracranial mass effect from SAH (increased ICP)
•Neurologic deficits and symptoms
•Timing, vasospasm

6. Preop
•One IV
•Premedicate with up to 2 mg of midazolam if
normal mental status.
•Remind of potential post op intubation
•Adequate fluid loading (5 to 7 ml/kg of LR,
angio)

7. Induction
•Routine monitors
•Propofol or thiopental
•Fentanyl 5 ug/kg in divided doses prior to
intubation
•Muscle relaxant (roc).
•Arterial cannula before intubation
•Avoid hypertension (propofol) and
hypotension (CPP, vasospasm)

8. Induction cont.
•Ceftriaxone 1 gm, 4-10 mg decadron, 1 gm/kg mannitol.
•Tape eyes with tagaderms (prep solution)
•Temp probe, foley
•Additional IV (limited access, 300 cc to liters of blood loss)
•Compression stockings

9. Positioning
•Supine, bump
•Long cases, lots of padding (pink and blue
foam)
•Table turned typically 90 degrees
•Head down?, aeroplaning
•After draping minimal/no access to face
(secure ET well)

10. Maintenance
•Oxygen
•Propofol infusion (50-200 ug/kg/min) (SSEPs, EEG)
•Inhalation agent (<0.25 MAC Isoflurane). Muscle
relaxation (vec, panc)
•Moderate hyperventilation (ET CO2 30 mmHg)
•Euvolemia to 500 cc more (LR)
•Moderate hypothermia (34 oC)

11. Burst supression
•When requested by surgeon
•Thiopental 125 mg (5 cc) doses
•Till 70-80% EEG burst supression
•Redose as needed
•Turn fentanyl infusion off
•Reduce propofol infusion rate
•Support CPP with phenylephrine infusion

12. Clipping
•Temporary clips (golden)
•Permanent clips (silver)
•Aneurysm manipulation before clipping (bleed)
•Record clip on/off times
•Maintain CPP during temporary clipping
•Start closing, warming and more fluid loading after
clipping

13. Toward the end
•First indication of end of surgery when clip
aneurysm (60 min)
•Normalize CO2 once dura closed or earlier if
lots of intracranial space
•Reduce propofol if possible, and titrate in
labetalol

14. Toward the end cont.
•Turn propofol infusion off about 10 min
before wakeup
•Reverse relaxation once Mayfied pins have
been removed
•Attempt to wakeup patient. Unlikely if more
than 1 gm of thiopental given.

15. Recovery
•Wake patient up as soon as possible
•Extubate if possible
•Prevent post op hypertension (bleed).
Labetalol
•Transport to ICU with monitor and oxygen
•Head up position

16. Potential Complications
•Delayed awakening from anesthesia
•Cerebral ischemia (retraction, temporary
clips, vasospasm)
•Brain swelling
•Intraoperative hemorrhage

17. Aneurysm rupture
•Reasonably common
•Intubation, pinning, skin insicion, surgical
manipulation
•Maintain intravascular volume (blood in the room,
get help)
•Maintain CPP
•Adequate anesthesia
•Thiopental before temporary clipping

18. Vasospasm
•Only if SAH
•5-14 days after SAH
•Leading cause of SAH morbidity (infarct)
•Maintain CPP at all times (neo infusion,
volume)
•HHH therapy
•Consider CVP measurement

19. What’s new?
•Retractor pressure
•Temp control
•Normotension

20. Surgical Steps
•Mayfield pins (stimulation), head positioning
•Shaving/prepping/local anesthesia
•Skin incision (stimulation, blood loss)
•Scalp off the bone (most stimulation)
•Burr holes, sawing
•Removing bone
•Open dura
•Surgical approach to aneurysm (microscope,
minimal stimulation, retraction)

21. Surgical Steps cont.
•Burst supression
•Temporary clips, permanent clip(s)
•Close (60 min)
•Dura (water tight)
•Bone flap
•Scalp and skin
•Dressing, remove pins