Regional Anesthesia :
Is it Worth the Effort?
Regional/APS Rotations
(Slides by Randall J. Malchow, MD)
Regional Anesthesia:
Is it Worth the Effort?
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Benefits- why should
we bother?
Risks- what are the
concerns?
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Decreasedn
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Regional AnalgesiaImprovement in
GA side effects/
complications
Opiate Side Effects
Blood Loss, DVT
LOS, Hosp Cost
Ileus, constipation, N/V
Stress Response
Chronic Pain
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Improvedn
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OR Efficiency
PACU Recovery and
rehab
Post-op Analgesia
Patient Satisfaction
Surgeon Satisfaction
Decreased Issues w
General Anesthesia
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CNS
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<Postop delirium
<Cognitive Dysfunction
<Drowsiness
Airway
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Cardiovascular
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<Sore throat, trauma
<Difficult airway
<Aspiration risk
<HR, BP changes
(avoiding intubation,
incision, emergence)
< Logistical
requirement
(monitoring, equip,
personnel)
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Waters, 1997, A&A
3rd World Application
Decreased Opiate
Complications
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Sedation- monitoring,
treatment
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B/T Cell Dysfunction
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(Payen, ’07; Lucas). >
sedation assoc w/ CV failure/
spt and death in ICU
Vallejo, ’04: < Ab prod, NK
cell activity, cytokine express,
phag act
Hypotension
Pruritis
Bladder Dysfunction
Opioid Induced Hyperalgesiauniversal w/ chronic use
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Respiratory Depression
n < use of basal rates on
wards
GI:
n Constipation/lleus
n Nausea/vomiting
Decreased Cost
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< Unplanned Admissions (outpts):
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< Length of Stay (LOS) Inpts w CPNB
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Williams ’04: 948 ACL cases reviewed
4% unplanned admissions (comp to 17%)
Annual Savings: 1.8 million based on 3000 outpt
ortho cases/yr
Vandy Pilot Study: Amputations, Trauma, Others
Duncan, Hebl, Mayo Clinic (2009 RAPM)
Epidurals:
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< ICU stay, hosp stay
Decreased GI Side
Effects, Blood Loss, and
DVT
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< N/V:
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GA: 13-32% vs cle for knee
scopes
Spinal: 12-18% (unopposed
vagal activity)
Epidural: 3-9%
PNB: 1-5%
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Mechanism:
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Sympathectomy w/ epidurals
Opiate sparing w/ all RA
< Constipation:
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< Blood Loss:
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< Post op Ileus:
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universal even w/ low dose
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Stevens, ‘2000: THA (60) <
Bld Loss in LPB grp
< Bld Loss w/ Spinals/Epid w/
THA
Mech: < BP as well as
avoiding positive pressure vent
(>CVP)
< DVT, PE:
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Epidural/Spinal studies in Total
Joints, Trauma, Vasc Pts
? Diff w DVT prophylaxis
Decreased Stress
Response
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What is it? (Desborough)
n SNS activation
n Endocrine response
n > pituitary (acth, gh, vasopressin)
n Insulin resistance
n Immune/heme changes
n Cytokine prod
n Lymphocyte prod
Correlates w/ severity of trauma (Seekamp)
Pain directly accentuates stress response
Effective Acute Pain mgmt < Stress Response
Decreased Chronic Pain:
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Acute Pain assoc with Chronic
Pain (Kehlet, Lancet)
Epidurals & Post Thoracotomy
Pain Syndrome: Obata, 1999, CJA
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Preop epidural, dose prior to
incision
Intraop infusion
Min IV narcotics
Avoid high conc of LA(>hypotension and motor
block)
PCEA beneficial: eg 8ml/hr;
2ml dose/30min
Toradol 15-30 mg qid x 2-3
days helpful (shoulder pain)
< Chronic Pain
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PVBs < Chronic Pain Breast
Surgery (Kairaluoma, 2006, A&A)
Amputations
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Bach, Pain, ’88
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RCT, prospective
Preop Epidural x 3d vs narcs
Postop: Meperidine/Tylenol
PLP: 0% Epid grp vs >30%
at 1 yr for narcotic grp
Fisher, A&A, 1991:
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AKA/BKA, older, vasc
(11) SCI CPNB placed intraop
Postop, B 0.25% x 3d
90% reduction in opioid
consumption
No PLP at 1yr.
Decreased
Respiratory
Complications:
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Epidurals
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Helpful w/ Long Bone Fx’s, Pelvic
Fx’s, Wound vacs
Improves Outcome for Thoracic/
Upper Abd trauma (Hedderich;
Ballantyne, 1998, A&A)
n < Atel, secretions, pneumonia,
resp failure,
n > cough, VC, paO2
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Rib Fractures:
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< pneumonia, ARDS; > cough,
DB, insp force, TV
< mech vent, ICU stay
Opioids synergistic w/ Local
anesthetics and more effective
w/ stress response
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PVBs and Rib Fx’s:
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Karmakar, Chest, 2003:
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Unilat MFR’s
T3-8 PVB caths
2-3cm in space (50%
difficulty)
20% contralat sprd; some
epid spread.
< VAS, RR; > SaO2, FRC, PEF
Decreased Mortality and MI
(Thoracic Epidural Analgesia)
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Rodgers, 2000, BMJ.
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30% decr mortality w/
epidural analgesia in
>9500 pts
Rib Fractures:
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< mortality 20% to 10%
(Victorini)
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Esp elderly w/ >> rib fxs
< MI, ischemia
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Beattie, 2001, A&A
> Cor Bld Flow
Improved OR Efficiencyn
Williams ’00: ACT+Turnover Times:
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Model: Block Room, staffed similar to BAMC
369 ACL, 3yr retrospective review, same surgeon, Penn.
Results:
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PNB
PNB + GA
GA
31 min
36 min
41 min
Decreased total “In-Room Anesthesia Time/ACT”
compared to GA
Recovery Fast Track
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Bypass Phase I
Minimal Phase II Recovery
Improved PACU Recovery
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Ford et al, 2001: 801 pts,
retrospective review (GA vs
PNB vs combined)
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Williams ’00: 369 ACL study
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< need to tx N/V (6% vs 20%)
< need for suppl O2 (12% vs
81%)
< discharge times (51min vs
104min)
< need to tx N/V (9% vs 39%)
< pain (14% vs 63%)
82% able to bypass PACU
(Williams)
Combined tech: intermediate
results
Less nursing care required
Improved Post-Op Analgesia and
Rehabilitation
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Excellent analgesia- up to 30
hours
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Horlocker, ’02: TKA w/ SAB
+LPB cath x 2d (0 narcotics
postop, only tylenol/ketorolac)
Mulroy, ’01: FNB for ACL’s.
24hr analgesia.
Minimal nursing requirement
Significant opioid sparing effect
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Total Joints and CPNB: 56 TKA: GA
w/ Cont Lumb Epidural (CLE) vs CFNB vs IV PCA x 3 days. Capdevila, ’99
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CLE and C-FNB: < pain, > ROM, <
Rehab time.
C-FNB < side effects
Improved Patient Satisfaction
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Wu ’01: Review Article on
Regional Anesthesia and Pt
Satisfaction; Meta-analysis
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Complex issue w/ many
determinants
18 trials comparing RA vs GA
ref pt satisfaction
70% trials RA> GA pt
satisfaction
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Borgeat, ’98: PCIA vs PCA,
shoulder: 9.6 vs 7.5
Vloka, ’97: FNB/GFNB vs
SAB: 100% vs 81%
Postop analgesia more critical
than intraop anes plan (pt sat)
Judicious sedation impt
Improved Surgeon Satisfaction
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Waters, A&A, ’97: 677 patients, all
Reg Anesthesia
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Day of Surgery Satisfaction Improved
"Can't really argue with
if:
results. Nobody wants to hear
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Minimize delay
No complications
High success rate
< Problems Postop:
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96% surgeon satisfaction
< Calls for Pain and PONV; ER visits;
< ALOS (ave length of stay) for inpts
> Pt referrals with Excellent Pain
Mgmt Program
patients cry about pain. I will
miss your service more than
any other at Vanderbilt. It
actually is one of the things I
most fear about leaving...not
having a quality pain service.“
- One of many Vandy surgeons
commenting on the APS
Upshot on Benefits:
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Widespread > Outcome: CNS, Cardiac, Resp,
GI, GU, LOS/Cost, Chronic Pain, Efficiency, and
Mortality
Continuous techniques (Cont Epid or CPNB):
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Amplify benefit
Richman:
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meta-anal of 19 studies in 603 CPNB pts:
< VAS, n/v, sed, pruritis
Thor Epidural Analgesia > Benefit than Lumbar
Combined w/ GA:
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Somewhat < benefit comp to RA alone
> Recovery times, > N/V
II. Risks- What are the
concerns?
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The “Big Three” PNB
Risks:
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LA Toxicity
Pneumothorax
Nerve Injury
Central Neuroaxis
Risks
Other
Local Anesthetic
Toxicity
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Prevention of LA
toxicity:
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Incidence of Seizures:
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Auroy, Anes 1997;
Brown, A&A, 1995
1:1000 rate with pnb
Usually not assoc w/
cardiac toxicity (even
w/ bupiv)
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Avoid Bupivacaine
Avoid Immobile
needle?
Extreme vigilance
while injecting
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IV injection poss even
w/ neg aspiration
Aspiration after every
5cc’s
Use of vasc marker w/
nerve stimulation
Recognize S&S of IV
injection
Local Anesthetic Toxicity
Treatment
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Rx Seizures ASAP
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Protect IV
Induction agent (propofol most common)
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Airway (from support to intubation)
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ACLS/CPR if necessary
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Intralipid immediately available (LA talk)
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Acidosis, anemia, hypoxia, hypercarbia,
and hyperkalemia all increase risk
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Amiodarone (vs lido), vasopressin (vs epi)
Defibrillation
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Dave Brown
Pneumothorax
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Supraclavicular:
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1-5% in some older series
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Franco: 0 ptx’s in 1001
SCB’s
Paravertebral:
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1:300 risk
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N.B. scoliosis, other
Interscalene (0.2%
Borgeat), Infraclavicular:
rare
Pneumothorax
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If concernedn
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avoid PPV/N2O
Consider CXR
Rtn to ER if CP, SOB
Chest Tube if >25% or
severe sx’s.
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Remember Other
Pulm Complications:
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Prevention:
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> training, education
Use of ultrasound
Closed systems
Phrenic Block (dep on
conc; eg anes vs
analg)
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ISB 100%
CPB 100%
SCB 40%
Bronchospasm:
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ISB
Nerve Injury
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ASA Closed Claims Proj,
1990,1999.
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Epineurium
Perineurium
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0.2-2% Incidence (defn, diff dx,
etc) Stan, ’95, Reg Anes.
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Endoneurium
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N. injury more common under GA
(61% of injuries under GA comp to
39% under Reg)
70% of UE inj assoc w/ GA
90% of LE inj assoc w/ RA (esp
SAB)
Incidence < w/ time; Borgeat, ’01,
ISB’s. 4% at 3mos, 0.2% at 9mos
No diff w/ CPNB vs single shot
(Bergman, ’03)
J. Hand Surg, ’96:
n
21% of Hand surg seen “major n.
inj” fr AXB.
Nerve Injury:
Incidence/Signs and Symptoms
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Incidence:
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Spinal: 1:1700
Epidural:
1:5000
PNB: 1:2500 (no difference w/ CPNB)
> Incidence in Diabetes, other (“Double Insult”
Signs/Symptoms of Intraneural Injection:
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Pain/Paresthesia
n
n
n
but not always
High Pressure
USG (nerve enlargement)
Nerve Injury- Mechanism
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Trauma
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Toxicity
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n
Needle
Stretch
Compression (eg
hematoma)
Injury/surgery
All local anesthetics
Adjuncts?
Ischemia
n
n
n
Tourniquets
Casts/splints
Intraneural injection
Nerve Injury
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Prevention:
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Communication, consent, sedation, avoid intraneural, avoid >>
conc, avoid >1:200k epi, use of Ultrasound?
1ml test dose (detect paresthesia, high pressure, and/or nerve
enlargement)
Never direct needle directly at nerve (only “6 and 12 o’clock”)
Gentle technique
Nerve Stimulation as tool to avoid intraneural injection (“neg
nerve stimulation at 0.5mA)
Treatment:
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Complete hx/PE: (diff dx… preexisting, surgical, posn,
tourniquet, other)
Symptomatic Rx w/ multimodal Rx (eg anticonvulsants)
Consider EMG/NCV studies
Reassurance
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“we wish to emphasize that spinal
anesthesia – conducted under routine
conditions in a standard manner- carries a
poorly understood potential for sudden
cardiac arrest in healthy patients.”
-Closed Claims Analysis
Bradycardia
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Vasovagaln
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ISB esp right side
sitting position
Early use of Atropine
Hypotension
n
Sitting- most common
Sedation premed
helpful
> young pts;
somewhat indep of
block level
Bezold-Jarisch Reflex
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n
n
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10% profound w/
Epidurals/spinals
NB elderly, hypovol.
Epinephrine toxicity
n
n
Cardiac
Risks
esp > 250mcg SQ/pnb
Cardiac Arrest:
n
1:1500 for spinals (vs
< 1:7000 for PNB and
epidurals) (Auroy, 1997,
Anes)
Other Risks
n
Other Central Neuroaxis
Risks:
n
PDPH:
n
n
n
n
Other PNB Risks:
n
n
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ISB’s 60%
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LPB (10%)
GA
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30% incidence
Avoid bupiv and epi
Epidurals
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ISB’s 15%
Soreness - 10-40%
“Failure” - 10%
Epidural Spread –
Spinals
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Hoarseness
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Urinary Retention:
n
Horner’s
n
2% w/ Pencil point needles
Age, guage, other factors
Lumbar > thoracic
5% incidence in hi risk
grps (hernia, GU,
perirectal)
Inability to Ambulate
(lumbar/low thor epidural)
n
Critical to place low thor
epidurals no lower than T10
n
Infection:
n
Incidence:
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n
Vascular Injury
n
n
Deep pain w/ abscess
Erythema, swelling
Temp, WBC late findings
Prevention:
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n
1<10,000 (single-shot)
1:1000 for epidurals
< 1% CPNB’s (dep
duration, other)
Signs and Symptoms
n
n
Infection and Vascular
Complications
Remove NLT POD4 (Home
caths)
DM, Steroids, Burns > risk
Treatment:
Vasospasm 1%
Hematoma 0.2%
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n
n
n
n
Klein, Anes ’97
Lovenox 30 bid
Lumb Plx Hematoma w/
plexopathy on POD9.
Rare Risk of hemorrhage
(Mult case rpts of
hemorrhage/ death w/ deep
PNBs in anticoagulated pts
Dissection, Aneurysm
Epidural Hematoma
n
Prevention:
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n
n
n
n
n
Avoid epidurals/spinals w/
coagulopathy, lovenox, plavix,
other
Know coag status prior to
placement and withdrawing
cath
Participate in DVT prophylaxis
plan
No significant risk w/ only
ASA, NSAIDs (altho additive
risk)
Excellent Update: RAPM, Jan/
Feb 2010
Signs and Symptoms:
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n
Increasing LE motor block,
Back pain (50%)
n
n
If concerned, < local anes
concentration, strict
observation w/ serial exams
(esp if intubated)
If positive S&S’s, MRI and
decompression within 8 hrs
Upshot with Risks
n
Remember the “Big
Three”
n
n
n
Improvements w/ LA
toxicity, Pneumothorax
Yet neuropraxia still
concerning
PNB/CPNB may <
Risks over Central
Neuroaxis (Giaufre, 1996, A&A)
n
Cardiac Arrest
n
n
Spinal assoc w/
greatest risk
Epidurals in Intubated
Pts
n
n
Very High risk
procedure
Check coags, volume
status, septicemia,
spinal injury concerns
Conclusion
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n
n
Benefits
Risks
Questions and
Answers?