preop neurology

1. PERIOPERATIVE MANAGEMENT OF
NEUROLOGICAL PATIENTS
BADER ALMASAAD

2. EPILEPSY
• People with epilepsy to be at significant risk of postoperative complications.
• Higher rate of postoperative complications when compared to patients without epilepsy (
OR=2)
• Most significant complication was stroke

3. CAUSES OF SEIZURES IN PERIOPERATIVE PERIOD
• Anesthesia
• Metabolic derangments
• Drug and alcohol withdrawal
• Intracranial surgery
• Underlying epilepsy , particularly when AEDs are stopped
• seizures that occur after surgery warrant investigation for secondary causes rather
than anesthesia related

4. ANESTHESIA REALTED SEIZURES
• Stage I ( excitation) and stage II (delirium) of anesthesia are the periods of greatest risk for seizure
activity.
• Inhalational anesthetics especially enflurane most common agent associated with seizures particularly
during induction and emergence
• Opioids can and are used to induce seizures so should be avoided
• Pethidine in large doses and especially if administred with MAO inhibitors
• Retrobulbar block for ophthalmic surgery
• IV anesthetic agents ( thiopental, methohexital, pentobarbital and propofol) are all anticonvulsant in
high doses, but can provoke seizure during induction and withdrawal.
• Incidence of seizures in epileptic patients due to anesthesia is around 1% in adults and 3% in children

5. MANAGEMENT OF DRUGS
• AEDs should be continued up to and during day of surgery
• Oral medications can be taken same day of surgery with sip of water
• They should then be restarted as soon as possible after surgery
• No need to assess drug levels preop in patient who is well controlled epileptic
• If patient cant take orally or needs intraop AEDs then IV administration should be
given

6. MANAGEMENT OF DRUGS
• Phenytoin, fosphenytoin, valproate, levetiracetam, phenobarbital and lacosamide
as well as benzodiazepines are available IV
• Carbamazepine can be given PR
• Many AEDs can be given as suspension via NGT
• Anesthetic agents do not significantly alter pharmacokinetics of AEDs so no need
to check drug levels post op unless patient sick with changes in albumin and pH
levels

7. MYASTHENIA GRAVIS
• Main concern is myasthenic crisis in the perioperative period
• Patients are unpredictably sensitive to nondepolarizing NMBA and are resistant to
depolarizing NMBA , eg succinylcholine

8. MYASTHENIA GRAVIS
• Elective surgery should be performed during stable phase of disease ( when patient is
well with minimal requirement of immunomodulatory meds)
• Surgery should be scheduled as early in the day as possible
• Patient should be evaluated for the following :
• bulbar symptoms
• History of myasthenic crisis or exacerbation
• Respiratory muscle weakness
• MG therapy
• Associated diseases , eg thyroid , rheumatoid etc

9. PREDICTION OF CRISIS: RISK FACTORS
• Vital capacity <2-2.9 litre
• Duration of MG >6 years
• Pyridostigmine dosage >750mg per day
• Hx of chronic pulmonary disease
• Preoperative bulbar symptoms
• History of myasthenic crisis
• Intraoperative blood loss more than 1 litre
• Serum anti ACHr antibody >100 nmol/ml
• More pronounced decremental response (18-20%) on low freq RNS

10. ANESTHESIA IN MG
• Avoidance of Neuromuscular blocking agents NMBA whenever possible
• Use of short acting sedatives, hypnotics and anesthetics
• Avoidance of premedications (eg benzos) if possible
• When possible, local or regional anesthesia should be preffered
• Avoidance of ester based local anesthetics eg, benzocaine
• Avoidance of high neuraxial block or brachial plexus block

11. ANESTHESIA IN MG
• Total intravenous anesthesia (TIVA) should be attempted
• High dose inhalational anesthesia can provide safer muscular relaxation
• If NMBA are absolutely necessary for the surgery
• Depolarizing NMBA eg succinylcholine , MG patients are resistant to this
requiring high doses of the agent to work.
• Nondepolarizing NMBA eg vecuronium, MG patients are sensitive to these
medications.
• Careful dosing and reversal of NMBA should be confirmed before extubation by
means of quantitative peripheral nerve monitor or RNS

12. MEDICATIONS TO AVOID
Anesthetic agents
Neuromuscular blocking agents*
Antibiotics
Aminoglycosides* - eg, gentamicin, neomycin, tobramycin
Clindamycin
Fluoroquinolones - eg, ciprofloxacin, levofloxacin, norfloxacin
Ketolides
¶
- eg, telithromycin
Vancomycin
Cardiovascular drugs
Beta blockers - eg, atenolol, labetalol, metoprolol, propranolol
Procainamide
Quinidine
Other drugs
Botulinum toxin
Chloroquine
Hydroxychloroquine
Magnesium
Penicillamine
Quinine

13. MEDICATION MANAGEMENT
• Pyridostigmine : should be continued up to and including the morning of
surgery, keeping in mind that they may affect response to NMBA.
If patient on long acting anticholinesterase it should be substituted with short
acting eg. Pyridostigmine from the night prior to surgery
If necessary can use rapid, short acting agents such as iv formulation. Dose is 1/30th
oral dose, eg. 30mg mestinon = 1mg IV
• Should be restarted after surgery as soon as patient hemodynamically stable

14. MEDICATION MANAGEMENT
• Steroids: may need stress dose steroid for surgery
• If patient taking steroids:
 less than 3 weeks
 <5mg of pred daily
 <10mg EOD
• Should continue same dose with no need for stress dose as they are not at risk of
hypothalamic pituitary axis suppression

15. MEDICATION MANAGEMENT
• Steroids:
• For those taking >20mg per day for more than 3 weeks or have cushingoid
appearance stress dose steroids should be given prior to induction of anesthesia
For minor procedures or surgery under local anesthesia (eg, inguinal hernia repair), take usual morning steroid dose. No extra supplementation is necessary.
For moderate surgical stress (eg, lower extremity revascularization, total joint replacement), take usual morning steroid dose. Give 50 mg hydrocortisone intravenously just before the
procedure and 25 mg of hydrocortisone every eight hours for 24 hours. Resume usual dose thereafter.
For major surgical stress (eg, esophagogastrectomy, total proctocolectomy, open heart surgery), take usual morning steroid dose. Give 100 mg of intravenous hydrocortisone before induction
of anesthesia and 50 mg every eight hours for 24 hours. Taper dose by half per day to maintenance level.
Corticosteroid coverage for surgery in patients taking exogenous corticosteroids

16. MEDICATION MANAGEMENT
• Immunotherapy:
• Continue as usual and skip morning dose
• Eg azathioprine, cyclosporine, mycophenolate mofetil, rituximab
• All have no proven effect on anesthesia in humans and can be safely omitted on day
of surgery as they have long half lives
• Treatment with one of the rapid immunotherapies (ie, plasmapheresis or intravenous
IG) for patients with preoperative respiratory or bulbar symptoms prior to any surgery
(Grade 2C)

17. LABOR IN MG
• Labor analgesia via spinal block is permitted with little or no complications
• First stage of delivery depends on uterine smooth muscle and is unaffected by
MG
• Second stage is as it depends on striated muscle, and patient may fatigue
requiring assisted delivery via vacuum or forceps
• For cesarean section, midthoracic level of spinal anesthesia is required which may
affect respiratory muscles, hence general anesthesia may be more appropriate

18. LAMBERT EATON MYASTHENIC SYNDROME
• General considerations
• Patients with LEMS are very sensitive to both nondepolarizing and depolarizing
agents.
• Hence avoid unless absolutely necessary
• If receive , use small doses and monitor with peripheral nerve stimulator
• Patients should continue their medication up to and including day of surgery, this
includes drugs such as guanidine and 3,4 diaminopyridine
• Autonomic dysfunction may result in exaggerated hypotension from anesthetic
agents and should be looked for and corrected with standard iontropes and
boluses

19. PARKINSONS DISEASE
• Patients with parkinsons disease have prolonged hospital stays and higher inpatient mortality
• Assessment of bulbar and respiratory function prior to surgery
Bulbar
• If patient has mod to severe parkinsons or complains of swallowing difficulty a barium swallow test should be done prior to
surgery, of abnormal then specific swallowing techniques can be taught to patient to minimize risk of aspiration
perioperatively
Respiratory
• Pre op ABG and PFT are useful as baseline
• Post op incentive spirometry, postural drainage and percussion are also useful
• Levodopa induced respiratory dyskinesia is a feature that may confuse ventilatory parameters of ventilator and should be kept
in mind

22. MEDICATION GUIDE
• Should continue dopamine replacement as close to normal as possible
• Do not discontinue dopamine ( risk of parkinsonism hyperpyrexia syndrome, akinetic state)
• Try to reduce dose of dopamine to lower doses that control symptoms to decrease risk of
withdrawal reactions later, this is if prolonged NPO status is anticipated post op
• Immediate post op prokinetic medications help reduce ileus and improve absorption of
subsequent tablets
• MAOB inhibitors should be discontinued 3 weeks prior to surgery, as interaction with certain
drugs can precipitate serotonin syndrome ( pethidine, fentanyl and certain anesthetic agents)

23. MEDICATION GUIDE
• Levodopa:
• Should be given up to and including day of surgery , can be given with sip of
water up to 1 hour before surgery
• Should be started again after surgery as soon as possible, for non abdominal
surgery this can be 2-3 hours after the operation
• Orally disintegrating form is available and should be kept in mind . Parcopa
• IV levodopa is available and used sometimes but has hemodynamic SE

24. MEDICATION GUIDE
• Dopamine agonists ( ropinirole, pramipexole, rotigotine): can be continued up to
surgery
• MAOB inhibitors: NO, avoid, if cannot be avoided, avoid drugs that interact with
them.
• Amantadine: can be continued perioperatively
• COMT inhibitors ( entacapone, tolcapone) : can be continued perioperatively
• Anti cholinergics: can be continued perioperatively but use low doses

25. SURGERY THAT REQUIRES STRICT FASTING: ABDOMINAL
SURGERY
• Manage with:
• rotigotine patches
• 300mg of levodopa = 8mg of rotigotine
• 8mg of ropinirole or 1.05 mg of pramipexole = 8mg of rotigotine
• Apomorphine SC injections every 3-4 hours. Dose should be determined beforehand
• Perform apomorphine test dose ( inject 2mg, then 3mg, then 4mg) identify dose where patient tolerates medication
with good clinical response. Then use dose - 1mg to start. (Max 6mg single
dose)
• Becareful with ondansetron as CI with apomorphine ( hypotension) ( 24 mg per day max)
• Anti emetics should be given , recommendation is PR domperidone

26. SURGERY REQUIRING COMPLETE FASTING FOR FEW
HOURS: NON ABDOMINAL SURGERY
• Medication should be restarted as soon as possible after surgery
• If patient drowsy or cant swallow can give through NGT.
• Can give sinemet tablet through NGT but need to dissolve in 10 ml of water first
and follow with water flush.
• Make sure to stop feed half hour before and after sinemet if patient taking high
protein feed ( >0.8mg prot/kg)

27. SURGERY THAT CAN BE PERFORMED WITH LOCAL OR
REGIONAL ANAESTHESIA AND THAT REQUIRES
PATIENT IMMOBILITY
• Example is ophthalmic surgery
• Dyskinesias and tremors become problematic
• Can time procedure during guaranteed on time with no dyskinesia if patient
history is known well and procedure is short
• Otherwise GA is preffered

28. ANESTHESIA ISSUES
• Propofol is the anesthetic of choice
• Thiopental decreases release of dopamine at striatal level and should be avoided
• Ketamine is CI ( sympathetic overresponse)
• Inhalational anesthetics should be avoided, esp halothane, isoflurane as they can
lead to hypotension and arrhythmias
• NMBA are generally safe, but preferred one is non depolarizing especially
rocuronium

29. PATIENTS WITH DBS
• Diathermy is contraindicated with functioning DBS, can lead to permanent brain
damage
• DBS must be turned off before surgery
• Record parameters prior to turning off

30. MUSCULAR DYSTROPHIES
• Malignant hyperthermia is the major concern
• It is a rare disorder of skeletal muscle calcium hemostasis resulting in build up of
calcium in the sarcolemma
• The anesthetic drugs that trigger it are the potent inhalational anesthetics and
succinylcholine
• Treated with dantrolene

31. MANAGEMENT
• Most common are DMD, BMD and EDMD
• In DMD there is bimodal clinical manifestations; during childhood where triggers during surgery can
lead to rhabdomyolysis and hyperkalemia, and during adulthood where progressive cardiac and
respiratory failure is the main concern
• Avoid inhalational anesthetics
• Avoid non depolarizing NMBA
• Aim for complete IV anesthesia
• Use Clean anesthetic machines
• Assessment of cardiac (ECG, ECHO) and respiratory (PFT, ABG) function prior to surgery
• Avoid or minimize opioids perioperatively

32. MITOCHONDRIAL MYOPATHIES
• Pre op cardiac and resp assessment, LFT, lactic acid and glucose measurement
• No absolute CI to anesthetic drugs, however care should be taken with NMBA
and propofol should not be used for prolonged time >48 hours ( risk of propofol
syndrome)
• In patients with lactic acidosis ( >90% of MELAS pts) excessive fasting and iv
solutions with lactate should be avoided.

33. MULTIPLE SCLEROSIS
• No specific anesthetic advice
• Only thing is possible association with spinal anesthesia and postoperative
exacerbation of symptoms
• Maintain perioperative and intraoperative temperature at room temperature and
avoid hyperthermia
• Medications for MS can be continued as usual and have no interactions, only
baclofen if used can cause sensitivity to NMBA
• Preop assessment of resp function if patient has respiratory compromise

34. NARCOLEPSY
• Higher risk of having apneic episodes, catplectic spells and sleep paralysis when
recovering from inhalational anesthesia
• Patients should continue medications up to day of surgery
• Patients have increased sensitivity to anesthetic agents and this should be kept in
mind by anesthetist
• Modafinil carries theoretical risk of increased awareness during surgery but many
patients on it tolerated surgery well and recommendation is to continue it

35. DEMENTIA
• Increased postoperative morbidity and mortality
• Care in avoiding precipitants of delirium
• Swallowing assessment
• Anti cholinesterases interact with NMBA and should be stopped 3-4 weeks before
elective surgery

36. STROKE
• In patient with recent stroke, surgery should be postponed if possible as mortality
risk increases as follows:
• 14.2% for 0 to 3 months,
• 4.8% for 3 to 6 months,
• and 2.5% for 6 to 12 months.
• The elevated risk appeared to level off after 9 months.

37. STROKE AND ANTIPLATELETS
• All patients receiving aspirin for secondary prevention following stroke should
continue on it and it should not be stopped for surgery.
• Except if operation carries a very high risk of bleeding eg. Closed space surgeries
• If stopping should be stopped 5-7 days prior to surgery

38. Name or class of drug Clinical considerations
Recommended strategy for surgery with brief
NPO state
Recommended strategy for surgery with
prolonged NPO state
Aspirin
Continuation may cause perioperative
hemorrhage.
Discontinuation may increase the risk of vascular
complications.
Discussion with cardiologist appropriate for
patients with cardiovascular indications.
Discontinue aspirin approximately 7 days prior
noncardiovascular surgery.
Resume with oral intake.
P2Y12 receptor blockers (clopidogrel, prasugrel,
ticlopidine, ticagrelor)
When used after cardiac stenting procedure, if
discontinued can cause cardiac ischemia
perioperatively. If continued can result in
bleeding complications. Should discuss
management with cardiologist.
Ideally, elective procedures should be delayed
until the mandatory period of platelet inhibition
with these agents is completed. When used for
long-term stroke prophylaxis, should be
discontinued 7 to 10 days. If discontinuing, stop
clopidogrel and ticagrelor at least 5 days,
prasugrel 7 days, and ticlopidine 10 days before
surgery. When restarting clopidogrel, consider
using a loading dose.
Resume with oral intake.
Warfarin Refer to UpToDate topic on anticoagulation before and after elective surgery.
Dabigatran Refer to UpToDate topic on anticoagulation before and after elective surgery.

39. Algorithm for perioperative management of antiplatelet therapy.
A. D. Oprea, and W. M. Popescu Br. J. Anaesth. 2013;111:i3-
i17
© The Author [2013]. Published by Oxford University Press on behalf of the British Journal of
Anaesthesia. All rights reserved. For Permissions, please email:
journals.permissions@oup.com

40. CLINICAL RECOMMENDATION EVIDENCE RATING REFERENCES COMMENTS
Aspirin must be continued preoperatively
when prescribed as secondary prevention of
cardiovascular disease or stroke.
A
20, 23 Meta-analyses of high-quality trials
20
and stent thrombosis studies
23
Early clopidogrel (Plavix) withdrawal (i.e., less
than six weeks after bare-metal stents, less
than six months after acute coronary
syndrome, less than 12 months after drug-
eluting stents) should be avoided because it
is the main predictor of coronary thrombosis.
B
18, 19, 24 Large prospective observational studies
Antiplatelet agents should not be interrupted
preoperatively because the risk of
cardiovascular events when withdrawing
them is generally higher than the risk of
surgical bleeding when upholding them.
B
3, 4, 14, 15,17, 30 Body of observational and quasi-experimental evidence favors this
recommendation, but randomized controlled trials are needed to ascertain it
Elective operations should be delayed
beyond dual antiplatelet therapy; operations
during dual antiplatelet therapy must be
performed without drug interruption.
B
3, 15, 25, 28 American College of Cardiology and American Heart Association
recommendations,
3,15
comparative clinical studies
25,28
Am Fam Physician. 2010 Dec 15;82(12):1484-1489.

41. STROKE AND ANTICOAGULATION
• If patient has recent stroke ( within 3 months) surgery should be postponed to at
least 6 months post event
• If surgery urgent, then proceed with stopping warfarin and bridging with heparin
• If patient has history of stroke> 6months then stopping warfarin beforehand
without bridging is adequate

42. THROMBOEMBOLIC RISK
Risk stratum
Indication for anticoagulant therapy
Mechanical heart valve Atrial fibrillation VTE
Very high thrombotic risk*
Any mitral valve prosthesis
Any caged-ball or tilting disc aortic valve
prosthesis
Recent (within six months) stroke or
transient ischemic attack
CHA2DS2-VASc score of ≥6
(or CHADS2 score of 5-6)
Recent (within three months) stroke or
transient ischemic attack
Rheumatic valvular heart disease
Recent (within three months) VTE
Severe thrombophilia (eg, deficiency of
protein C, protein S, or antithrombin;
antiphospholipid antibodies; multiple
abnormalities)
High thrombotic risk
Bileaflet aortic valve prosthesis and one or
more of the of following risk factors: atrial
fibrillation, prior stroke or transient ischemic
attack, hypertension, diabetes, congestive
heart failure, age >75 years
CHA2DS2-VASc score of 4-5 or
CHADS2 score of 3-4
VTE within the past 3 to 12 months
Nonsevere thrombophilia (eg, heterozygous
factor V Leiden or prothrombin gene
mutation)
Recurrent VTE
Active cancer (treated within six months or
palliative)
Moderate thrombotic risk
Bileaflet aortic valve prosthesis without
atrial fibrillation and no other risk factors for
stroke
CHA2DS2-VASc score of 2-3 or
CHADS2 score of 0-2 (assuming no prior
stroke or transient ischemic attack)
VTE >12 months previous and no other risk
factors

43. BLEEDING
RISK
High bleeding risk procedure (two-day risk of major bleed 2 to 4 percent)
Abdominal aortic aneurysm repair
Any major operation (procedure duration >45 minutes)
Bilateral knee replacement
Coronary artery bypass
Endoscopically guided fine-needle aspiration
Heart valve replacement
Kidney biopsy
Laminectomy
Neurosurgical/urologic/head and neck/abdominal/breast cancer surgery
Polypectomy, variceal treatment, biliary sphincterectomy, pneumatic dilatation
Transurethral prostate resection
Vascular and general surgery
Low bleeding risk procedure (two-day risk of major bleed 0 to 2 percent)
Abdominal hernia repair
Abdominal hysterectomy
Axillary node dissection
Bronchoscopy ± biopsy
Carpal tunnel repair
Cataract and noncataract eye surgery
Central venous catheter removal
Cholecystectomy
Cutaneous and bladder/prostate/thyroid/breast/lymph node biopsies
Dilatation and curettage
Gastrointestinal endoscopy ± biopsy, enteroscopy, biliary/pancreatic stent without sphincterotomy, endosonography without fine-needle aspiration
Hemorrhoidal surgery
Hydrocele repair
Knee/hip replacement and shoulder/foot/hand surgery and arthroscopy
Noncoronary angiography
Pacemaker and cardiac defibrillator insertion and electrophysiologic testing
Tooth extractions

44. WARFARIN
• If deemed necessary to discontinue, stop 5 days prior to surgery, resume 12-24 hrs
post op
• Check INR on day of surgery, if above 1.5 may give vitamin k 1-2 mg
• If going to bridge ( V. high risk of thromboembolism eg, recent stroke, mechanical
heart valve, CHADS2 score of 5 or 6) then give:
• LMWH eg clexane 3 days prior to surgery continued to 24 hours pre op OR
• unfractionated heparin continued 3 days prior to surgery continued to 4 hours pre op
• Both can be restarted 24 hours post op unless difficult hemostasis delay until 48 hours
post op

45. DABIGATRAN
• Can be stopped 2 days before surgery in patients with normal or mild renal
impairment
• Can be stopped 4 days before surgery in patients with severe renal impairement
• No need for bridging pre op
• Bridging post op if patient will be NPO for prolonged period eg GI surgery
• Start post op once hemostasis achieved , keep in mind it will reach full effect
within 12 hours so delay if in doubt
• Usually 1 day post low risk of bleed surgery and 2-3 days post high risk surgery

46. RIVAROXABAN
• Stop 2-3 days pre op, depending on bleeding risk of operation
• No need for bridging pre op
• Bridge post op if prolonged NPO
• Can monitor factor Xa in select cases to check if it is normal ie drug cleared from
system
• Restart 2-3 days post op once hemostasis achieved

47. APIXIBAN AND EDOXABAN
• Exact same recommendation as rivaroxaban

48. EXAMPLE CASE SCENARIO
• A 76 year old female with non-valvular atrial fibrillation, hypertension, and prior stroke three months
ago, receiving warfarin, requires elective hip replacement with neuraxial anesthesia; renal function is
normal, and weight is 75 kg. This patient has a very high thromboembolic risk and a high bleeding risk.
• •Stop warfarin five days before the procedure (last dose on preoperative day minus 6).
• •Preoperative bridging with dose LMW heparin (eg, dalteparin, 100 units/kg [7500 units]
subcutaneously twice daily) starting on preoperative day minus 3, with last dose on the morning of day
minus 1.
• •Resume warfarin within 24 hours after surgery (usual dose).
• •Postoperative low dose LMW heparin for VTE prevention (eg, dalteparin 5000 units subcutaneously
once daily) within 24 hours after surgery until postoperative bridging is started.
• •Postoperative bridging on postoperative day 2 or 3, when hemostasis is secured (eg, dalteparin, 100
units/kg [7500 units] subcutaneously twice daily; continue for at least four to five days, until the INR is
therapeutic.

49. CAROTID ASSESSMENT
• Evaluation of the carotid arteries in patients with an asymptomatic carotid bruit is
not warranted
• Evaluation is however warranted if the patient is going for cardiac surgery eg
CABG
• Evaluation is also warranted if the patient has history of stroke or TIA and going
for surgery

50. CAROTID ASSESEMENT
• If patient for CABG and carotid assessment shows
• <80% stenosis then proceed for CABG only ( no difference in mortality if doing
CEA at same time)
• 80-99% stenosis then proceed for both CABG and CEA at same time ( lower
mortality)
• If patient has symptomatic carotid stenosis and planned for surgery eg stroke or
TIA on same side then,
• Delay surgery and proceed for CEA first

51. VERTEBROBASILAR DISEASE
• Limited data , shows increased risk of perioperative stroke? Approx 6%
• No advice or guidelines available
• Optimized patient as much as possible