REGIONAL ANESTHESIA IN CHILDREN
From Regional Anesthesia in Children, sponsored by Children’s Hospital and Regional Medical Center, Seattle, WA
Educational Objectives
| The goal of this program is to improve continuous perineural catheter techniques and to provide better understanding of the
surgeon’s perspective of regional anesthesia in children. After hearing and assimilating this program, the clinician will be
better able to:
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 | 1. Review the history of continuous perineural catheter techniques and indications for its use in children.
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| 2. List the technical considerations and equipment choices used in continuous perineural catheter blocks.
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| 3. Identify possible anesthetic solutions and complications associated with continuous peripheral nerve blocks.
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| 4. Describe the surgeon’s objectives for regional anesthesia during surgery.
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| 5. Through the surgeon’s perspective, examine various anesthetic options, potential anesthetic complications, and adjunctive
treatments to decrease postoperative pain associated with pediatric surgery.
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Faculty Disclosure
In adherence to ACCME Standards for Commercial Support, Audio-Digest requires all faculty and members of the planning
committee to disclose relevant financial relationships within the past 12 months that might create any personal conflicts
of interest. Any identified conflicts were resolved to ensure that this educational activity promotes quality in health
care and not a proprietary business or commercial interest. For this program, the faculty and planning committee reported
nothing to disclose.
Acknowledgements
Drs. Larkin and Schmale spoke in Seattle, WA, at Regional Anesthesia in Children, held September 8-9, 2007, and
sponsored by Children’s Hospital and Regional Medical Center, Seattle. The Audio-Digest Foundation thanks the
speakers and the Children’s Hospital and Regional Medical Center for their cooperation in the production of this program.
| CONTINUOUS PERINEURAL CATHETER TECHNIQUES —Kathleen Larkin, MD, Clinical Assistant Professor of Anesthesiology,
University of Washington School of Medicine, and Attending Anesthesiologist, Children’s Hospital and Regional
Medical Center, Seattle, WA
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| Introduction: many pediatric anesthesia providers nervous about placing neuraxial block in sedated child; tremendous
future for continuous peripheral nerve catheters for postoperative pain management in children; risk thought to be lower
than performing neuraxial blockade in sedated child; rise in continuous peripheral nerve block (CPNB) due to increased
confidence and growing expertise with ultrasonography (US; able to see catheter next to nerve and bolus local anesthesia
around nerve); speaker believes CPNB catheters will replace single-shot nerve blocks and epidurals for many orthopaedic
pediatric procedures
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| General concepts: studies available for CPNB catheter use in adults, but not many in children; safer now with advances
in equipment, drugs, US, and nerve stimulator
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| History: first documented use of CPNB in 1946; performed supraclavicular block with blunt needle end, using paresthesia
technique; secured catheter through cork into supraclavicular block; gave boluses periodically for 48 hr; in 1950s, stiletted
catheter placed through introducer needle; used to verify location near nerve; first pediatric case of CPNB in 1976;
15-yr-old boy with avulsed finger and multiple tendon lacerations received brachial plexus block with continuous catheter;
in 2006, French authors looked at pediatric regional anesthesia practice over previous 17 yr; before 1995, CPNB used
sparingly; in last 10 yr, dramatic increase in CPNB use; increase also seen in children
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| Indications for pediatric use: sympathectomy for right pulmonary sinus (RPS) nerve area; 90% of CPNB used for
lower extremity; CPNB also used in upper extremity, especially psoas compartment block
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| Technical considerations: use smallest needles available; problems occur with small needles and small catheters; may
have trouble directing catheter with small needle; small catheter has tendency to kink and dislodge easier; also, consider
variations in compartment fluid volume, skin thickness, connective tissue thickness, and bone growth in children; distance
from skin to perineural tissue not linear with age; distance from posterior superior iliac spine (PSIS) to intercristal
line most likely approximation of distance required for twitch with psoas compartment block; avoid muscle relaxants;
when placing catheter, approach similar to single-shot technique remember to give test dose; do not advance catheter >1
to 2 cm past tip to avoid displacement or kinking; secure catheter carefully in child
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| Equipment: choices of introducers include plastic catheter (metal stylet used to stimulate) and insulated needle (Tuohy
needle can be used to direct catheter; better approximation of angle of catheter when exiting needle); epidural catheters
used in past; now use stiletted catheter and stimulating catheter (improving success rate); many catheter fixation systems
available; ideal to have infusion system that provides continuous infusion (results in better analgesia; much safer
in children at risk for toxicity or accumulation); patient-controlled analgesia (PCA) ideal but not as available for continuous
peripheral nerve catheter
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| Tunneling: many catheters become dislodged when using this method of fixation (eg, axillary block); in certain positions,
may be worth considering tunneling; subgluteal block can be easily tunneled laterally; if patient cannot tolerate opioids
afterwards or requires aggressive physical therapy, consider tunneling to allow longer duration of analgesia
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| Ideal infusion pump: should be lightweight to promote early mobility, have wide range of infusion rates for varying sizes
and ages, and should be PCA to provide optimal analgesia with minimal amount of local anesthetic agent; safety features
important; elastomeric or electronic pumps with fixed infusion rates sent home mostly with adults, but also children;
some take PCA pump home
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| Anesthetic solutions: any anesthetic can be used in pediatric doses; combination short-acting and long-acting agents
used to provide optimal dose in operating room (OR); more research needed with continuous peripheral nerve catheter;
recent study in adults indicates giving bolus through needle or catheter equally successful for nerve coverage with axillary
block; when using 2 nerve catheters (eg, femoral and sciatic), count doses of both to avoid overdose
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| Infant considerations with local anesthetics: fat less dense; local distribution easier; systemic absorption faster
due to increased cardiac output; α1 glycoprotein low until age 9 mo, so free-fraction higher; study on ropivacaine found
no accumulation in infants when used in epidurals for ≤96 hr; speaker tends to start peripheral nerve catheters, with bupivacaine
or ropivacaine, at 0.1 mL/kg per hour
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| Complications: rare; more complications due to positioning or surgical issues than to CPNB; most catheters removed
within 48 hr; likelihood of infection extremely low; most common calls from nurses on floor because of leaking; if working,
reinforce and continue; if not working, remove; second most common call because catheter has fallen out; 24-gauge
catheter has tendency to kink; other complications include incomplete block and block that is too dense (if necessary, decrease
dose or concentration)
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| Practical considerations: multimodal multidisciplinary approach necessary for CPNB to work properly and efficiently;
includes surgeons, nurses, physical therapy (PT), and pharmacy; much education necessary for nurses and parents;
establish guidelines for regular assessment; know whom to call when questions arise; order adjuvant pain
medications as needed; pain team or anesthesia provider must see child daily; check catheter site daily; debatable when to
remove catheter after use; some suggest leaving in place for 12 to 24 hr (impractical in busy high-turnover day-surgery);
if child comfortable on oral pain medications, speaker removes catheter after 4 hr; order heel protectors for child with
lower extremity nerve catheter; call pain service for signs of overdose, anticoagulation, or pending magnetic resonance
imaging (MRI) in stimulating catheter
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| Study results: perceived advantages of CPNB, compared to epidural, include less risk for spinal cord injury, bladder
catheterization, and unilateral motor block; psoas compartment catheter seems to provide better postoperative analgesia
than intravenous (IV) opioid techniques
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| Future: CPNB “the way of the future for postoperative pain control”; definite decrease in single-shot blocks and, hopefully,
epidurals also; many children with chronic pain go home with catheter in place
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| THE SURGEON’S PERSPECTIVE ON REGIONAL ANESTHESIA —Gregory A. Schmale, MD, Associate Professor of
Orthopaedics and Sports Medicine, and Program Director, Orthopaedic Medical Education, University of Washington
School of Medicine; Program Director, Orthopaedics Resident, and Clinical Chief, Sports, Children’s Hospital and Regional
Medical Center, Seattle
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| Surgeon’s objectives: safe, reliable, effective, and efficient anesthesia (if patient uncomfortable, time savings negated;
concerned overnight and into next day with management of patient who has become problematic; family interaction issues
escalate when pain inadequately controlled); anesthesia choices should be understood and agreed upon by entire
team; easy transition to hospital floor and then home; minimal nausea; low complication rates after discharge; no surprises
when block wears off (speaker prefers peripheral catheters because of capability of managing pain at night; transition
to oral analgesia during day); easy analgesia delivery at home (no nausea; easy to administer; few side effects)
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| Anesthesia options: general anesthesia (GA) with local anesthetic infusion—fast, easy, reliable, and low complication
rates; however, once local anesthetic wears off, postoperative pain control ineffective; studies suggest bupivacaine
alone, infused locally into joint or soft tissue, provides little analgesia beyond time of action; high risk for nausea; addition
of spinal or epidural—not as fast acting, but reliable; complication rates slightly higher; less nausea due to less GA
use; single-shot may wear off at night; infusion with epidural catheter may lead to delayed discharge (eg, issues of urinary
retention; may be necessary for motor blockade to wear off); concern about missed compartment syndrome; peripheral
nerve block—less nausea; good analgesia; requires fewer supplemental pain medications; when catheter placed,
less worry about pain when regional anesthesia wears off; historically, results in longer placement times during early
transition phase; may be less reliable with less experience; risk for complications high (more in upper extremity than
lower extremity)
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| Compartment syndromes: pain number one sign of increased pressure in enclosed fascial space; pain out of proportion;
high narcotic requirement; little pain relief with treatment; pain may occur with passive stretch; muscle weakness
may occur in involved compartments; loss of sensation seen later; speaker believes pallor and pulselessness are signs of
vascular disease, not signs of compartment syndrome; silent compartment syndromes occur in children (pain not present;
only signs are loss of motor function and swelling of limb; motor function returns after fasciotomy); minimize complications
by working within comfort zone, knowing procedure to be performed, performing procedure frequently, doing it
same way each time, knowing anatomy, and limiting unnecessary risks (eg, if patient comes to emergency department with
minimally displaced tibia fracture, speaker frequently admits overnight; would not choose regional technique that increases
difficulty in detecting compartment syndrome; regional anesthetic chosen only if motor function not blocked or if
anesthetic can be stopped to determine return of motor function)
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| Speaker’s institution: decrease OR time by placing block in block room (requires more staffing); transition from block
team expertise to entire anesthesia department expertise in placing blocks (experience equals greater efficiency and
greater safety); communication between pain service, surgical team, and anesthesia “better all the time”
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| Future possibilities: catheters with disposable pumps (improves discharge times); home-nursing visit (confirmation of
supplemental medication and monitoring for pain and nausea)
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| Alternatives for knee surgery: study looked at local infusion at portal site 30 min before surgery (1% lidocaine, 20
mL with epinephrine at skin incision site, and 0.5% bupivacaine, 30 mL with epinephrine); some patients received intra-
articular morphine and mild sedation with midazolam and fentanyl; results included decreased recovery time and improved
postoperative pain control; speaker injects 0.25% bupivacaine, 20 to 30 mL with epinephrine (helps control
bleeding); provides minimal postoperative pain relief; inadequate for bony surgery (eg, anterior cruciate ligament [ACL]
reconstruction); risk for local anesthetic toxicity (adjust dose carefully), and risk that information on preference cards
may be incorrect (indicate location for arthroscopy)
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| Adjunctive treatments that may be useful to decrease postoperative discomfort: pretreatment with nonsteroidal
anti-inflammatory drugs (NSAIDs)—review of 25 studies found significant differences in postoperative pain
scores when >4 mg of intra-articular morphine was provided at end of knee procedure; 1 to 2 mg showed almost no difference
in postoperative pain scores; another study suggested greater analgesia immediately postoperatively with increased
morphine injection (higher doses equalled greater analgesia); intra-articular injection of bupivacaine at case
completion—review of 20 studies found only 12 that revealed significant decrease in postoperative pain; differences only
lasted 1 to 4 hr (possibly until postanesthesia care unit [PACU] discharge); study by Tran found femoral and sciatic nerve
blocks had significantly lower intraoperative fentanyl requirement, significantly less recovery room pain, lower morphine
requirement via PCA in first 18 hr after surgery, less vomiting, and longer time before requiring PCA; speaker suggests
combination intra-articular medication and nerve blocks would be optimal; study conducted in adults that looked at peripheral
catheter vs PCA with home infusion postoperatively vs block with low continuous infusion of local anesthetic and bolus
capability; found pain scores significantly higher in PCA group at 4 hr and 12 hr and 1 to 3 days; more fatigue, nausea
and vomiting, and dizziness in PCA group; continuous infusion group had greater persistent paresthesias and fear of falling;
low infusion tended to work best; pretreatment with opioids—study in adult hysterectomy and abdominal surgery
found morphine and fentanyl decreased postoperative pain; costs include increased nausea and vomiting
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| NSAIDs and other cyclooxygenase-2 (COX-2) inhibitors: study by Reuben looked at pretreatment medications
1 to 2 hr before ACL reconstruction; 100 patients given acetaminophen and celecoxib, 400 mg; other group received acetaminophen
and placebo; those getting celecoxib required less fentanyl and oxycodone, had significantly less nausea and
vomiting, and significantly shorter PACU stay; used less oxycodone through 14 days, had less pain at rest and with activity
through 14 days, and better functional knee scores at 6 mo; speaker dose not use COX-2 inhibitors in ACL reconstruction;
concerned about bone ingrowth of graft to tibia and femur and fixation; COX-1 inhibitors block conversion of
prostaglandins in gastric mucosa, kidney, and intestine; COX-2 inhibitors primarily block inflammatory prostaglandins,
with fewer systemic side effects; most NSAIDs have COX-1 and COX-2 activity (celecoxib one of few COX-2 inhibitors
on market); prostaglandins that induce pain also early product of fracture callous; contribute to osteoblast signaling and
stimulation during maturation of fracture callous; increase bone resorption and osteoclast activity; encourage remodeling
of callous; key to maturation of callous and formation of new bone; anything that inhibits prostaglandins of concern because
of effect on bone healing; COX-1 inhibits platelet function; platelet key in forming clot that serves as scaffold for
initiation of fracture callous formation; COX-1 and COX-2 both block prostaglandin D and E; slow both osteoblast and
osteoclast activity; numerous animal studies suggest decreased mechanical strength of fracture callous after using
NSAIDs; Glassman study on effect of postoperative NSAIDs on spinal fusion found nonunion rate 5 times greater when
1 to 12 doses of postoperative ketorolac, 60-mg load followed by 30 mg IV q6hr, was used in adults; more doses increased
likelihood of nonunion; studies in rats given COX-2 inhibitors suggest decreased mechanical integrity of fracture
callous (differences resolved by 30 days; unsure whether clinically significant)
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| Surgeon’s requests: if placing blocks, follow up and note successes and failures; protect against complications (think
about what might occur and use prophylaxis to avoid problems); get involved in studies to better understand efficacy
of treatment
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Suggested Reading
Brown KM et al: Effect of COX-2-specific inhibition on fracture healing in the rat femur. J Bone Joint Surg Am 86-
A:116, 2004; Dadure C et al: Continuous epidural block versus continuous popliteal nerve block for postoperative pain
relief after major podiatric surgery in children: a prospective, comparative randomized study. Anesth Analg 102:744, 2006;
Fredman B et al: The analgesic efficacy of patient-controlled ropivacaine instillation after Cesarean delivery. Anesth
Analg 91:1436, 2000; Glassman SD et al: The effect of postoperative nonsteroidal anti-inflammatory drug administration
on spinal fusion. Spine 23:834, 1998; Klasen JA et al: Intraarticular, epidural, and intravenous analgesia after total
knee arthroplasty. Acta Anaesthesiol Scand 43:1021, 1999; Michelet P et al: Adding ketamine to morphine for patient-
controlled analgesia after thoracic surgery: influence on morphine consumption, respiratory function, and nocturnal desaturation.
Br J Anaesth 99:396, 2007; Mulroy MF et al: Femoral nerve block with 0.25% or 0.5% bupivacaine improves
postoperative analgesia following outpatient arthroscopic anterior cruciate ligament repair. Reg Anesth Pain Med 26:24,
2001; Murnaghan M et al: Nonsteroidal anti-inflammatory drug-induced fracture nonunion: an inhibition of angiogenesis?
J Bone Joint Surg Am 88 Suppl 3:140, 2006; Reuben SS et al: Evaluating the analgesic efficacy of administering
celecoxib as a component of multimodal analgesia for outpatient anterior cruciate ligament reconstruction surgery. Anesth
Analg 105:222, 2007; Reuben SS et al: The effect of initiating a preventive multimodal analgesic regimen on long-term
patient outcomes for outpatient anterior cruciate ligament reconstruction surgery. Anesth Analg 105:228, 2007; Slater
ME et al: Preliminary evaluation of infraclavicular catheters inserted using ultrasound guidance: through-the-catheter anesthesia
is not inferior to through-the-needle blocks. Reg Anesth Pain Med 32:296, 2007; Tiseo BC et al: Experimental
study of the action of COX-2 selective nonsteroidal anti-inflammatory drugs and traditional anti-inflammatory drugs in
bone regeneration. Clinics 61:223, 2006; Tran KM et al: Intraarticular bupivacaine-clonidine-morphine versus femoral-
sciatic nerve block in pediatric patients undergoing anterior cruciate ligament reconstruction. Anesth Analg 101:1304,
2005.
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