REGIONAL ANESTHESIA IN 2006
| DIAGNOSIS AND MANAGEMENT OF PERIPHERAL NERVE BLOCK COMPLICATIONS —James B. Mayfield,
MD, Assistant Professor and Vice Chairman for Clinical Services, Department of Anesthesiology and Perioperative Medicine,
and Medical Director of Perioperative Services, Medical College of Georgia, Augusta
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| Goals in regional anesthesia: provide safe and effective regional anesthetic experience; evaluate, diagnose, and manage
injuries related to nerve blocks
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| Establishing regional anesthesia program: specific patient-care processes should be in place before placing block (eg,
training postanesthesia care unit [PACU] nurses; take-home information for patient; tracking and follow-up issues)
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 | Nursing education: institution may have anesthesiologists give in-service training to PACU nurses
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| Patient education: take-home information should provide brief explanation of regional anesthesia, warnings to protect
numb extremity, expected duration of block, notice of follow-up telephone call, and contact information
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| Patient tracking: include patient name, contact information, date of surgery, attending surgeon, anesthesia providers, type
of block, issues with block placement, and initial follow-up information
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| Timely problem evaluation: within 24 hr, if possible; provide professional place to evaluate problem (eg, pain clinic in
emergency department)
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| Interdisciplinary cooperation: surgeon can provide information about candidacy for regional block (eg, patient does not
follow instructions; psychosocial issues not conducive to complex regional block); good working relationship with radiologist,
neurologist, and pain clinic
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| Radiologic evaluation: should be done in timely manner; ask for emergency add-on time slot, when necessary
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| Available referral services: eg, multidisciplinary pain clinic, neurology clinic
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| Monitors and equipment: standard monitors to place block (eg, electrocardiography [ECG], pulse oximetry, noninvasive
blood pressure cuff); if opportunity arises, automatic anesthesia record capture system; documentation on computer
easier to read postoperatively and easier to store in central location; medications, equipment, nerve blocks, and needles
ready before start
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| Patient identification: determine location of procedure before placing block; identify patient; time-out system helps ensure
correct patient and correct site
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| History and physical examination: document preexisting medical conditions that may be relevant
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| Patient education: help patient understand what happens before placement of block, as opposed to trying to explain problems
after placement; explain block technique, use of nerve stimulator, common side effects, anticipated duration of
block, and postoperative pain medication follow-up plan
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| Appropriate sedation: patient should be comfortable, still, and awake (to detect paresthesia and signs of local anesthetic
toxicity); must be able to answer simple questions, follow simple commands, and provide appropriate feedback;
speaker prefers fentanyl 50 to 150 µg for block placement (mild sedative; pain relief)
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| Block documentation: goal to help future colleagues know what has been effective and to help determine causality if injury
occurs (electromyography [EMG] does not indicate cause); causality may provide better prognosis or more appropriate
treatment if injury occurs; helpful information includes block technique approach, minimum current achieved with
nerve stimulator, types of sedation, local anesthetics and adjuvants used, any immediate side effects and reactions (eg,
blood aspiration, increased pressure, pain), and extent of block; should also contain information about need for general
anesthesia due to incomplete block, need for additional local anesthesia by surgeons, any surgical problems (especially
shoulder), and total tourniquet time
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| Early patient follow-up: 24 to 48 hr after block; goal to assess effectiveness, patient satisfaction, and whether further follow-up
necessary; document follow-up, effectiveness of block to control pain, duration of block, effectiveness of postoperative
pain medication, sign of infection or hematoma at block site, and residual numbness or weakness
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| Identification of problems: any affirmative answer to questions involving infection, residual numbness, motor deficiency,
pain not associated with surgery, or surgical issues requires seeing patient in follow-up as soon as possible; before seeing
patient, review documentation of block; review perioperative course with patient; perform new physical examination and
compare with physical examination before block; get patient’s perspective about cause of problem; decision to refer
based on extent of sensory deficits, motor involvement, significance of pain, and possible surgery-related issues
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| Electrophysiologic testing: predominant methods of testing include EMG (muscle electrical activity) and nerve conduction
studies (function of motor and sensory nerves); important in defining neurogenic basis of nerve damage, localization
of site of injury, severity of injury, and possible prognosis; does not indicate exact etiology of nerve injury; testing
may confirm existence of lesion, localize lesion, suggest whether lesion old or new, indicate severity, guide prognosis
and likely recovery, and determine whether injury complete or evolving; cause of lesion must be inferred from perioperative
record and clinical evaluation; prognosis made by determining cause and severity of lesion
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| Timing: as early as 2 to 3 days postoperatively; can reveal presence of lesion and specific site; may be appropriate to repeat
in 4 to 6 wk to give injury time to evolve; serial studies not generally necessary, unless nerve transection complete;
follow healing process clinically
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| EPIDURAL ANESTHESIA IN OPEN ABDOMINAL AORTIC ANEURYSM (AAA) REPAIR —Peter K. Schoenwald,
MD, Staff Anesthesiologist, Department of General Anesthesiology, and Emeritus Head, Section of Vascular Anesthesia,
Cleveland Clinic Foundation, Cleveland
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| Outcome: unclear whether cardiac morbidity or mortality changes with use of epidural technique; other variables include
length of hospital stay and quality of pain control
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| Stress response: skin incision results in release of cytokines into blood stream; cytokines reach hypothalamus and pituitary
gland and cause release of adrenocorticotropic hormone (ACTH), antidiuretic hormone (ADH), growth hormone, and
thyroid-stimulating hormone (TSH); neuroendocrine responses also occur, mediated by sympathetic afferents and sensory
afferents; sympathetic efferents reach adrenal gland and liberate catecholamines (eg, epinephrine, norepinephrine),
cortisol, renin, and aldosterone; results in changes in heart rate, coagulation system, immune system, and metabolism
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| Cardiac effects: epinephrine and norepinephrine liberated from adrenal gland into blood stream; also modulated when pain
sensed by brain moves down spinal cord directly through autonomic efferents (T1 to T4); heart rate and blood pressure
increased (positive inotropic effect on heart; affects O2 balance by increasing O2 demand, shifting supply-demand ratio,
and potentially causing ischemia); ischemic response attained easily in patient with clinical coronary artery disease
(CAD) and in subgroup of patients who have subclinical disease and never had symptoms
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| Studies: Breslow, in 1992, reported on group of patients undergoing aortic surgery; demonstrated that epinephrine and
norepinephrine rise preoperatively, but with differential response; norepinephrine level stays increased for at least 24
hr after surgery; epinephrine level drops to normal within 6 hr after arrival in intensive care unit (ICU); also showed
similar response in lower extremity revascularizations; study by Hertzer in 1984 looked at method to decrease morbidity
and mortality in peripheral vascular surgery; 1000 coronary arteriograms; 26.3% had AAA as primary diagnosis;
high proportion had CAD; ≈60% had advanced or severe CAD, of whom 25% had severe correctable CAD; 14% of
those with surgical CAD had no symptoms or indications; 30% of AAA candidates had preoperative coronary artery
bypass graft (CABG); of those with AAA, severe disease 34%, correctable lesion 31%
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| Yeager study: small sample size; mix of surgical populations and procedures, including aortic surgery; postoperative epidural
management inconsistent; evaluated effect of epidural anesthesia and analgesia on morbidity; study group given
light general anesthesia plus epidural; continued epidural into postoperative period for pain control; study group had
lower mortality, lower complication rate, less cardiovascular failure, fewer major infections, lower cortisol levels initially,
and lower hospital costs
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| Tuman study: studied major vascular surgery patients; examined effect of epidural addition to anesthetic plan on outcome
and coagulation; found vascular surgery patients to be hypercoagulable as shown by thromboelastography (TEG) testing
preoperatively and one day postoperatively; hypercoagulability attenuated with epidural; also had less thrombotic events
and reduced rates of cardiovascular, infectious, and overall postoperative problems with epidural; ICU stay also reduced
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| Baron study: unable to demonstrate decrease in cardiac morbidity or mortality between anesthetic techniques in aortic surgery;
did not control or randomize use of epidural anesthetic into postoperative period; other studies also unable to show
beneficial effects
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| Park study: no significant difference found between groups in mortality or major morbidity, until subgroups analyzed; aortic
surgery patients had fewer major complications and reduced mortality rates
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| Additional studies: 2 meta-analyses in 2000 and 2001 showed positive effects with regional anesthesia; but others state
that proposed benefit from regional anesthesia “remains unproven”
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| Epidural cooling: decreases incidence of neurologic complications after thoracoabdominal aneurysm repair; certain
authors have reported dramatic results in preventing spinal cord ischemia; results by other groups not uniformly reproducible
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| Minimally invasive techniques: designated fluoroscopy equipment to insert, from peripheral sites and arteries, endovascular
stents for aortic repair; avoids ICU stay; enables surgery on sicker patients; decrease overall hospital stay
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| EPIDURAL ANESTHESIA IN RADICAL PROSTATECTOMY —Jacek Cywinski, MD, Assistant Professor, Department
of General Anesthesiology, Cleveland Clinic Foundation, Cleveland
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| Indication for radical retropubic prostatectomy (RRP): prostate cancer most commonly diagnosed cancer in men; those
with clinically localized prostate cancer and life expectancy ≥10 yr tend to undergo RRP
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| Surgical technique: involves en bloc removal of entire prostate gland, seminal vesicles, ejaculatory ducts, and portion of
bladder neck, while attempting to preserve nerves controlling sexual function; after procedure, remaining bladder neck reanastomosed
to urethra over indwelling urinary catheter; limited lymphadenectomy performed to facilitate staging of cancer
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| Technique of RRP: vertical incision below umbilicus; potential for significant blood loss during dorsal vein dissection;
urine output after transsection of urethra cannot be measured and therefore cannot be used as indicator of intravascular
volume status; average surgical time 180 min and average blood loss 600 to 1800 mL
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| Anesthetic choices for RRP: include general, epidural, combined general and epidural, spinal, and combined spinal and
epidural
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| Potential advantages of regional anesthesia for RRP: decreased respiratory and cardiac morbidity; decreased intraoperative
blood loss; better postoperative pain control; lower incidence of postoperative deep venous thrombosis (DVT); faster
postoperative recovery
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| Potential disadvantages of regional anesthesia for RRP: sympathectomy—activation of epidural catheter can blunt
compensatory response to bleeding, induce hypotension, and may require more intravenous fluids; patient comfort may
be compromised, especially in longer procedures
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| Shir studies: patients randomized to 3 groups; epidural—induced with bupivacaine 0.5%, then continuous infusion titrated
to maintain adequate intraoperative block; epidural with general anesthesia—before surgical incision, epidural
catheter activated with bupivacaine 0.5%; continuous infusion throughout surgery; general anesthesia—epidural
catheter placed but no medication delivered intraoperatively; postoperative management—identical for all patients;
fentanyl 100-µg bolus; epidural patient-controlled analgesia (PCA) initiated
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| Study 1: results—groups did not differ in postoperative pain, bleeding, urine output, fever, and length of hospital stay;
no major cardiovascular, pulmonary, or neurologic events; conclusion—no difference in major outcomes; intraoperative
anesthetic technique does not affect postoperative outcomes; sample size probably too small to detect significant
difference in rate of major complications or major morbidity
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| Study 2: results—those with entire surgery under epidural anesthesia had significantly less blood loss than other 2
groups; also less blood transfusion required during surgery in epidural group, compared to other groups; conclusion—
similar blood loss in patients receiving general anesthesia, either alone or combined with epidural anesthesia, implies
that epidural anesthesia did not reduce bleeding but, rather, general anesthesia increased blood loss
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| Study 3: results—PCA demand greater in epidural with general and general anesthesia alone groups as compared with epidural
group on postoperative days 2 and 3; no difference in PCA demand between epidural with general and general anesthesia
alone in entire postoperative period; no significant difference in postoperative mean pain scores between groups in
first 5 days after surgery; conclusion—lower postoperative analgesic requirements in epidural group indicates that epidural
group had less pain and that efficient intraoperative blockade of noxious afferent signals to central nervous system
(CNS) fundamental in reducing postoperative pain
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Educational Objectives
| The goal of this program is to educate the listener about regional anesthesia. After hearing and assimilating this program,
the clinician will be better able to:
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| 1. Summarize the steps in establishing a peripheral regional anesthesia program and outline the preblock protocol.
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| 2. Describe the evaluation and management of complications associated with peripheral nerve blockade.
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| 3. Discuss the outcome studies in use of epidural anesthesia and/or analgesia in aortic surgery.
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| 4. Explain the potential role of epidural cooling in thoracoabdominal aortic repair.
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| 5. Outline the indication for and technique of radical retropubic prostatectomy (RRP) and discuss the role of different
anesthetic techniques for RRP.
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Discussed On This Program
Bupivacaine HCl (several trade names)
Epinephrine (several trade names)
Fentanyl citrate [Sublimaze]
Midazolam HCl [Versed]
Morphine sulfate (several trade names)
Procaine HCl [Novocain]
Sodium bicarbonate [Bell/ans, Neut]
Suggested Reading
Baron JF et al: Combined epidural and general anesthesia versus general anesthesia for abdominal aortic surgery. Anesthesiology
75:611, 1991; Breslow MJ: Changes in myocardial blood flow rates during hyperdynamic sepsis. Crit Care
Med 21:1112, 1993; Breslow MJ: The role of stress hormones in perioperative myocardial ischemia. Int Anesthesiol Clin
30:81, 1992; Christopherson R et al: Perioperative morbidity in patients randomized to epidural or general anesthesia for
lower extremity vascular surgery. Perioperative Ischemia Randomized Anesthesia Trial Study Group. Anesthesiology
79:422, 1993; Gold MS et al: The effect of lumbar epidural and general anesthesia on plasma catecholamines and hemodynamics
during abdominal aortic aneurysm repair. Anesth Analg 78:225, 1994; Hertzer NR et al: Coronary artery disease
in peripheral vascular patients. A classification of 1000 coronary angiograms and results of surgical management. Ann Surg
199:223, 1984; Mayfield JB: Diagnosis and management of peripheral nerve block complications. Int Anesthesiol Clin
43:119, 2005; Park WY et al: Effect of epidural anesthesia and analgesia on perioperative outcome: a randomized, controlled
Veterans Affairs cooperative study. Ann Surg 234:560, 2001; Rigg JR et al: Design of the multicenter Australian
study of epidural anesthesia and analgesia in major surgery: the MASTER trial. Control Clin Trials 21:244, 2000; Shah S
et al: Neurologic complication after anterior sciatic nerve block. Anesth Analg 100:1515, 2005; Shir Y et al: Intraoperative
blood loss during radical retropubic prostatectomy: epidural versus general anesthesia. Urology 45:993, 1995; Shir Y
et al: Postoperative morbidity is similar in patients anesthetized with epidural and general anesthesia for radical prostatectomy.
Urology 44:232, 1994; Shir Y et al: The effect of epidural versus general anesthesia on postoperative pain and analgesic
requirements in patients undergoing radical prostatectomy. Anesthesiology 80:49, 1994; Sprung J et al: Ischemic
liver dysfunction after elective repair of infrarenal aortic aneurysm: incidence and outcome. J Cardiothorac Vasc Anesth
12:507, 1998; Yeager MP et al: Epidural anesthesia and analgesia in high-risk surgical patients. Anesthesiology 66:729,
1987.
Faculty Disclosure
In adherence to ACCME guidelines, the Audio-Digest Foundation requests all lecturers to disclose any significant financial
relationship with the manufacturer or provider of any commercial product or service discussed. For this issue, the faculty reported
nothing to disclose.
Dr. Mayfield was recorded at Daily Anesthetic Challenges, presented June 9-12, 2005, by the Medical College of Georgia,
and held in Kiawah Island, South Carolina; Drs. Schoenwald and Cywinski, at Survey of Current Issues in Surgical
Anesthesia—Preparation, Choices, and Outcome, presented October 30 to November 3, 2005, by the Cleveland Clinic
Foundation, and held in Naples, Florida. The Audio-Digest Foundation thanks the speakers and the sponsors for their cooperation
in the production of this program.
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