lecture i gave it in 15 of oct 2014 in university hospital ground round about anesthesia for parkinson disease

1. ANESTHESIA FOR
PARKINSON DISEASE
PATIENT
Rizq Alamri

2. OUTLINES
• Parkinson disease
• Deep brain stimulation surgery and its anesthestic
concerns
• anesthesia for patients with pre-existing deep brain
stimulator systems

3. Parkinson’s Disease is increasing
• Affects 1 in 100 older than 60 years
• 5-10% diagnosed with PD are less than 40 yrs. old
• No social, ethnic or geographical boundaries
Projected Increase in Prevalence of PD by 2030
Dorsey et al.2007

4. BIOCHEMICAL PATHOLOGY
• is decreased dopamine neurotransmission in
the basal ganglia.
• most parkinson syndromes have
degeneration of the nigrostriatal dopamine
system with marked loss of striatal
dopamine.
• in some – striatal degeneration with loss of
dopamine receptors occurs.

5. Motor Cortex
Putamen
Premotor
Cortex
Motor
Thalamus
+ Glutamate
Gpe
- GABA
Gpi
STN
Dopamine
SNpc
+
-
PATHWAYS
1

6. Motor Cortex
Putamen
Premotor
Cortex
Motor
Thalamus
+ Glutamate
Gpe
- GABA
Gpi
STN
Dopamine
SNpc
+
-
PATHWAYS
2

7. Motor Cortex
Putamen
Premotor
Cortex
Motor
Thalamus
+ Glutamate
Gpe
- GABA
Gpi
STN
Dopamine
SNpc
+
-
PATHWAYS
3

8. INITIAL SYMPTOMS OF PARKINSON
DISEASE
• 60% of substantia nigra dopaminergic
neurons already lost at onset
• Dopamine content of striatum is only 20% of
normal
• Motor symptoms are prominent , i.E. Tremor,
stiffness & slowness, loss of dexterity, gait
disturbance, and muscle aches, pains and
cramps.
• S.N. Pathology: black brown tan

9. SIX CARDINAL FEATURES
Rest tremor
Rigidity
FLEXED POSTURE
BRADYKINESIA – HYPOKINESIA
LOSS OF POSTURAL REFLEXES
FREEZING PHENOMENON
TO DIAGNOSE: two of above with at least being rest tremor OR bradykinesia

10. NON-MOTOR SYMPTOMS OF
PARKINSON DISEASE
• Behavioral symptoms :depression, anxiety,
decreased motivation, personality changes,
less inclination to speak, bradyphrenia
• Sensory non-specific pains, akathisia, restless
legs and other sleep problems
• Autonomic constipation, bladder
dysfunction, impotence, low blood pressure

11. Pharmacological Treatment of
Parkinson’s Disease
• Goals:
• Primary = restore dopamine receptor function.
• Secondary = inhibition of muscarinic cholinergic receptors.
• Several types of drugs:
• Levodopa
• Dopamine Receptor Agonists
• Monoamine Oxidase Inhibitors (MAOIs).
• Catechol-O-Methyltransferase (COMT) inhibitors.
• Muscarinic Cholinergic Receptor Antagonists.
• Amantidine.

12. Pharmacological Treatment of
Parkinson’s Disease
From: Youdim et al. 2006. Nature Rev Neurosci. 7: 295-309

13. CURRENT SURGICAL INTERVENTIONS
• Thalamotomy/ Thalamic
Stimulation
• Mainly used for tremor - essential,
MS
• Other targets preferred for PD
• Pallidotomy/Pallidal Stimulation
• Effective for all cardinal features
Considerable experience
• Subthalamic Stimulation
• Most recent addition
• Several theoretical advantages
• Currently most popular therapy

14. DEEP BRAIN STIMULATION
• is used to treat Parkinson disease and other
neurologic conditions, as well as certain psychiatric
disorders
• The indications for DBS have now expanded to
include other conditions, and the number of
centers performing this procedure has also
increased .
• The DBS system provides advantages over
traditional surgical ablative procedures such as
thalamotomy and pallidotomy, because it is non-destructive,
reversible, and adjustable

15. PATIENT SELECTION
• Inclusion Criteria
- Idiopathic Parkinson's Disease
- Symptoms for four or more years
- Documented response to levodopa
therapy
- Medically refractory disease?
• Exclusion Criteria
- Patients unable to communicate
- Patients unable to cooperate for
surgery
- Dementia
- Abnormalities on pre-operative MRI
- Medical contraindications to surgery
• Movement Disorders Team Evaluation
- Initial screening
- Insure that medical therapy is optimized
- Neurologic evaluation using validated
clinical rating scales
- Psychiatric Evaluation
- Neuro-psychologic Evaluation
- Neurosurgical Evaluation
- Consensus opinion at weekly
conference

16. • The deep brain stimulation (DBS) hardware has
three main components:
1. Multicontact intracranial quadripolar electrodes
2. A programmable single- or dual-channel internal
pulse generator (IPG) with battery unit
3. An extension cable connecting the DBS electrodes
to the IPG

17. • Stage one : is
usually done
under sedation.
• Stage two : is
usually done
under General
anesthesia.

18. DBS TARGET SITES FOR MOVEMENT
DISORDERS
Vim Thalamus:
Essential Tremor
Subthalamic Nucleus:
Parkinson’s disease
and Dystonia
Globus Pallidus:
Parkinson’s disease
and Dystonia

19. SUBTHALAMIC NUCLEUS
• Subthalamic nucleus is small (5 x
7 mm) and difficult to visualize
using current MRI and CT
technology

20. BRAIN MAPPING
Frame-based imaging to identify the target
nuclei
Target localization with the use of
microelectrode recording
Macro stimulation testing

21. FRAME-BASED IMAGING
• A stereotactic head frame is
usually applied using local
anesthesia
• With the stereotactic frame in
place, magnetic resonance
imaging (MRI) is performed to
identify target nuclei, allowing
the surgeon to establish
external coordinates for
electrode insertion.
• Alternatively, computerized
tomography (CT) scanning can
be used, if MRI is
contraindicated or not possible
in an individual patient.

22. MICROELECTRODE RECORDING
• Is a fine tune
localization of the
target sites.
• The
neurophysiology
team obtains MERs
to detect and
amplify the activity
of individual
neurons

23. MICROELECTRODE RECORDING
Stereotactic Localization
Micro Drive
• A microelectrode is inserted to a point 10
to 15 mm above the target, then slowly
advanced in 0.5 to 1.0 mm increments
while its tip records and amplifies neuronal
discharges along its path.

24. 1
2
3
4
5
6
7
8
9
10
11
12
Depth in (mm)
Para-sagittal Section - 12 mm lateral
Thalamus
Zona
Incerta
Tremor
Cell
Subthalamic
Nucleus
Electrode
Trajectory
1 sec
PHYSIOLOGIC
LOCALIZATION

25. MACROSTIMULATION TESTING
• the patient is awake during surgery, allowing the team to
briefly activate the implanted deep brain electrode in
order to confirm clinical improvement (efficacy) and
detect any adverse side effects during neurostimulation

26. PREOPERATIVE EVALUATION AND
PREPARATION
• Use of the stereotactic head frame and airway
compromise:
regardless of the original anesthetic plan,
meticulous airway assessment is imperative to assess
the risk of potential airway compromise and to
formulate a plan for urgent airway management.
all equipment necessary to remove the stereotactic
head frame should be immediately available
throughout the procedure.

27. • Blood pressure control:
Hypertension is a common perioperative problem
and is associated with increased risk of intracerebral
hemorrhage.
It is important to treat hypertension immediately to
minimize the risk of intracerebral hemorrhage during
electrode insertion.

28. • long-standing Parkinson disease
autonomic dysfunction
 impaired respiratory reserve
poor cough reflex
sleep apnea
increased risk for aspiration

29. • challenging Patient:
Patient with psychiatric condition
Patients with chronic pain require special
consideration

30. INTRAOPRATIVE CARE
After applying appropriate monitoring
Sedation drug selection:
Novel drug should be:
Airway and respiratory sparing
Attenuate responses to surgical stimulation
Does not interfere with Microelctrode recording or
macrostimulation and patient evaluation.

31. • Dexmedetomidine :
 a dose of (0.3 to 0.6 mcg/kg/hour) provides
sedation from which patients are easily aroused
and cooperative with verbal stimulation.
 Low-dose infusion does not ameliorate clinical signs
of Parkinson disease, and anxiolysis can be
achieved with no effect on MER

32. • Propofol has been widely
used as a continuous
infusion, either alone or in
combination with opioids,
especially in cases involving
lead placement in the
subthalamic nuclei
The extent to which
propofol interferes with MER
localization is not clear,
although it is known to
cause dyskinesia and
abolish tremor
Propofol has the desirable
properties of rapid onset
and short duration of
action.
• Short acting opioids are
commonly used as
analgesics because of
their minimal effect on
MER
Opioids may cause
worsening of rigidity
especially in high doses
• Benzodiazepines should
be avoided as these
drugs can abolish MER
and also interfere with
stimulation testing

33. PERIOPERATIVE COMPLICATIONS IN DBS
• Airway and respiratory
complications 1.6 to 2.2 %
• Hypertension is a common
perioperative problem
• Hypotension may occur
due to autonomic
dysfunction
• Venous air embolism can
occur at any time during
the burr hole procedure,
either in the supine or in
the semi-sitting position
especially in a
hypovolemic patient
The incidence of venous
air embolism is reported to
be 4.5%

34. PERIOPERATIVE COMPLICATIONS IN DBS
• Seizures: are the most common neurological
complication, occurring in 0.8 to 4.5 % of patients
having DBS placement
• Intracranial hemorrhage is rare
Intracranial hemorrhage is suspected in an awake
patient when there is a sudden change in mental
status or occurrence of a focal neurological deficit

35. POSTOPERATIVE CARE
• vigilance of the hemodynamic and respiratory
parameters in the immediate postoperative period
as increased chances of respiratory depression
present
• Care must be taken to start antiparkinsonian drugs
as soon as possible, either through the nasogastric
tube or orally to avoid potential risk of exacerbation

36. DBS Improvement in PD
“ON” Time Without Dyskinesias Improves from 27% to 74%
49%
27%
23%
Before Surgery
(n=96)
74%*
19%
7%
6 Months After Surgery
Bilateral STN Implant
(n=91)
‘ON’ with Dyskinesia ‘ON’ without Dyskinesia ‘OFF’
* The Deep-Brain Stimulation for Parkinson’s Disease Study Group. Deep-brain stimulation of the subthalamic nucleus for the
pars interna of the globus pallidus in Parkinson’s disease. N Eng J Med. 2001;345:956-63.

37. PD MOTOR SYMPTOMS IMPROVEMENT
MAINTAINED AFTER 5 YEARS
• In a 5-year study, DBS significantly improved OFF-medication
assessments of tremor, rigidity, and akinesia/bradykinesia
OFF-Medication Motor Score Improvements*
6-month 1-year 3 years 5 years
Tremor 79% 75% 83% 75%
Rigidity 58% 73% 74% 71%
Akinesia 42% 63% 52% 49%
*Results for STN

38. Journal of the Formosan Medical Association DOI: (10.1016/j.jfma.2013.09.006)
Copyright © 2013 Terms and Conditions

39. OVERALL COMPLICATION

40. ANESTHESIA FOR PATIENTS WITH PRE-EXISTING
DEEP BRAIN STIMULATOR
SYSTEMS
• identification of the device and the status of the
severity of the patient’s symptoms when the
implanted DBS system is turned off.
• If deactivation of the device results in severe
symptoms, oral medication should be started
before turning the device off on the day of surgery.

41. ANESTHESIA FOR PATIENTS WITH PRE-EXISTING
DEEP BRAIN STIMULATOR
SYSTEMS
• DBS systems may produce artifacts and
interfere with the recording of an ECG
• Intraoperative electrocautery has the
potential to burn neural tissue around the
stimulator or to reprogram the device
• Use of bipolar electrocautery is safer

42. • the paddles must be positioned as far away
as possible from the generator and the
lowest clinically-appropriate energy output
should be used
• Electroconvulsive therapy, radiofrequency
neuro-ablation, and peripheral nerve
stimulation have been reported to be safe if
the stimulator is turned off and the probes
are placed far away from the generator

43. CONCLUSION
• There is good evidence from randomized controlled
trials to endorse deep brain stimulation (DBS) of
either the subthalamic nucleus (STN) or the internal
globus pallidus (GPi) as an effective therapeutic
option for
• DBS is non-destructive, can be performed bilaterally
with low neurologic morbidity
• DBS surgery is growing up in functional brain surgery
including psychiatric and behavior illness