Kiddie-CaudalsCaudal Epidural Analgesia in Everyday Pediatric

Practice

Sabine Kost-Byerly, MD, FAAPAssociate Professor and Director, Pediatric Pain Management

Department of Anesthesiology/Critical Care Medicine

Johns Hopkins University, Baltimore, Maryland

Objectives

Upon completion of this lecture, the attendee will be able

to:

• Appreciate the technical aspects of caudal analgesia

• Select appropriate local anesthetic solutions for caudal

analgesia

• Recognize and manage complications of caudal epidural

analgesia

Disclosures

• I have no relevant financial relationships

with manufacturers of any commercial

products or providers of commercial

services discussed in these slides.

Caudal Epidural Analgesia

caudal

lumbar

thoracic Advantages:

Easy to performHigh success rateUsually no hemodynamic changes

Caudal Epidural - Indications

• Surgeries:– Urologic– Orthopedic– general

• Locations:– lower abdomen– lower extremities

• Regional Alternatives to consider:– Peripheral nerve block– Truncal block– Extremity blocks

Demographics for 13,725 patients in the Pediatric Regional Anesthesia Network (PRAN) database.

Anesth Analg 2012;115:1353-64

Single Injection Caudal Placement by Age by age.

Polaner D M et al. Anesth Analg 2012;115:1353-1364

Caudal Block in Children: Technique

• Position: lateral decubitus, knees flexed

• Landmarks: sacral cornuea at sacral hiatus

• Needle position: 45°-60° angle to coronal plane

• “pop” : piercing the sacro-coccygeal membrane

• Reduce angle to 10°-20° and advance a few mm

Kiddie- Caudal - Single Injection

• Needle:– 22-g needle– 22 – g angiocath

• (risk: epidermal-cell graft tumor – but: no reports)

– 22-g short-beveled, styletted needle

Caudal BlockIdentification of Landmarks

Post sup iliac

spines

Sacral cornu

Caudal BlockPlacement of Cannula

Caudal Block in ChildrenNo Touch Technique Distance to Caudal Space

Location, location…is your needle where it should be?

Clinical Assessment

• The “pop” – the sacrococcygeal membrane

– No visible/palpable subcutaneous injection

• The whoosh (air) test– Risk: patchy block, venous air

embolus

• The swoosh (NS) test– Risk: dilution of LA

Technical Aides

• Ultrasound– Experience, assistant

Tiffterer l et al. Br JAnaesth 2012;108;670-4

Testdose – sometimes the caudal IV is the easiest…

• Aspiration • Avoid patient simulation• Dose

– Epinephrine 0.5 mcg/kg in 0.1 mL/kg of LA

• Continuous ECG monitoring– T-wave changes >25% increase– HR increases– BP increases

• Inject rest of LA dose slowly in increments

Results:742 pediatric epidural blocks 644 caudal 284 single caudal injections

42 (5.6%) Intravascular injection 3.8% with single caudal injections

Detection:6 immediate aspiration of blood30 HR increases >10 bpm25 T-wave amplitude increases29 ECG changes in T-wave or rhythm

Amide Local Anesthetics• Lidocaine

• Bupivacaine

• Ropivacaine

• Sodium channel blockers

• Protein binding– 65% (lido.)– 95% (bupiv., ropiv.)

– Α1 acid glycoproteine (AAA), albumin• Neonate low AAA: ↑ free fraction of LA

• Metabolism:– cytochrome P450 system

• CYP3A4 for bupivacaine and lidocaine– Bupiv. at 1 mo 1/3 of adult, at 6 mo 2/3

• CYP1A2 for ropivacaine– Max for ropiv not reached till age 5

Choice of LABupivacaine:• Slower onset, longer

duration• Cardiac toxicity>CNS

toxicity

• Single dose– 1 mL/kg of 0.25%

bupivacaine– max <2.5 mg/kg

• “Ideal”: concentration– 0.125 - 0.175% comparable

duration of analgesia, less motor block

Ropivacaine:• Duration similar• Less motor block at

lower concentrations• Less toxicity

• Single dose– 1 mL/kg 0.2% ropivacaine

Choice of LALidocaine:

• Short onset, medium duration

• CNS toxicity>cardiac toxicity

• Single dose– up to 5-7 mg/kg

Chloroprocaine:

• Short onset, short duration• Advantageous toxicity

profile

• Single dose– up to 14 mg/kg - or more

Epidural Additives – improved and prolonged analgesia

The Common

Opioids• Inpatients only

– Fentanyl 2 mc/kg– Morphine 12-50 mcg/kg

• Pruritis, emesis, respiratory depression

Clonidine• Alpha -2-agonist• Single dose 1-2 mcg/kg

– Risk: bradycardia, apnea in young infants

– Increasing sedation with higher doses

The Rare

• Continued concerns of safety for neuroaxial use:– preservative, ph, neurotoxicity

• Ketamine 0.25 – 1 mg/kg• Neostigmine 2 mcg/kg

– Emesis common

• Midazolam 50 mcg/kg• Dexmedetomidine 1-

2mcg/kg– Analgesia similar to clonidine

• Tramadol 2 mg/kg

Caudal single Injection – Volume

• Correlation between cranial level and volume• Exact prediction of level not possible• Volumes < 1 ml/kg not likely to reach higher than L2 • Speed of injection does not matter Brenner L et al. Br J Anaeth

2011; 107:229-35; Tiffterer l et al. Br JAnaesth 2012;108;670-4

Thomas L< et al. Paediatr Anaesth 2010;11:1017-21

• Volume for injection:– 0.5 ml/kg for perineal surgery– 1.0 ml/kg for lower abdominal surgery– 1.25 ml/kg for upper abdominal surgery

Volume versus Concentration

• RCT• Bupivacaine with epi O.8 mL/kg 0.25% B vs 1 ml/kg 0.2

% B

• Lower GA requirement with higher volume• Maybe better postop analgesia with higher volume

Vergehese ST et al. Anesth Analg 2002;95:1219-23

ComplicationsCommon:

• Pruritis• Nausea & emesis• Sedation• Urinary retention

Rare, but serious

• Systemic toxicity– Inadvertent IV injection

• Overdose– Inadvertent IT injection

• Infection/Hematoma/Neuropathy

Risk of Systemic LA Toxicity

• 10,098 epidurals– 8493 caudals– 7 with transient ECG changes – no treatment

Pediatric Anesthesia 2010;20:1061-1069

ASRA Recommendations – Prevention of LAST Neal JM et al. Reg Anesth Pain Med 2010;35:152-61

• Lowest effective dose of local anesthetic • Incremental injection of local anesthetics • Aspirate the needle or catheter before each injection • Use of an intravascular marker (epinephrine) is

recommended.

• Ultrasound guidance may reduce frequency of intravascular injection– Effectiveness remains to be determined

ASRA - recommended LAST -Management

• ABC’s• Seizures:

– Benzodiazepines, small dose propofol – avoid large dose propofol for risk of CV compromise– Succhinylcholine or other NDMB , small doses to minimize acidosis and hypoxemia

• Cardiac arrest – ACLS , but

• epinephrine - small initial doses (10mcg to 100 mcg boluses in the adult) preferred• Vasopressin not recommended • Calcium channel blockers and A-adrenergic receptor blockers – avoid• Amiodorone for ventricular arrhythmias, treatment with local anesthetics (lidocaine or procainamide) not

recommended

– Lipid emulsion therapy -Consider administering at the first signs of LAST, after airway management• 1.5 mL/kg 20% lipid emulsion bolus• 0.25 mL/kg per minute of infusion, continued for at least 10 mins after circulatory stability is attained• Consider rebolus if circulatory stability is not attained and increase infusion to 0.5 mL/kg per minute (up to 10

mL/kg lipid emulsion within 30 mins)– Propofol is not a substitute for lipid emulsion

– Cardiopulmonary bypass• failure to respond to lipid emulsion and vasopressor therapy• notify the closest facility capable of providing it when CV compromise is first identified during an episode of LAST.

Neal JM et al. Reg Anesth Pain Med 2010;35: 152-61

Lipid emulsion therapyConsider administering at the first signs of LAST, after airway management

1.5 mL/kg 20% lipid emulsion bolus0.25 mL/kg per minute of infusion, continued for at least 10 mins after circulatory stability is attained

Consider rebolus if circulatory stability is not attained and increase infusion to 0.5 mL/kg per minute (up to 10 mL/kg lipid emulsion within 30 mins)

Propofol is not a substitute for lipid emulsion

Intralipid for LA-induced Cardiotoxicity in infants

• 2-day-old 3.2 kg term infant– Caudal, 1 mL/kg 0.25% bupivacaine, with US guidance and confirmation– VT, cardiovascular collapse– 20% Intralipid 1 ml/kg – recovery Lin EP et al. Pediatric Anesthesia

2010; 20:955-7

• 40-day-old, 4.96 kg infant– Caudal, 0.9 mL/kg 0.25% bupivacaine– Tachycardia, T-wave inversion hypotension– Epinephrine 2 mcg/kg x2, 20mL 55 albumin – no change– 20% Intralipid 2 ml/kg – recovery Shah S et al. J Anesth 2009; 23:430-41

TD DP

VP

AB FB C R N Other

Total Events

Total Procedures

%

Caudal 18

5 38

71

26

1 0 0 13 172 6011 (97%)

2.9

Lumbar 0 2 0 2 0 0 0 0 1 5 103 4.9

Thoracic

0 1 0 1 0 0 0 0 0 2 13 15.4

Sub-arachnoid

/ / 0 2 2 1 0 0 1 6 83 7.2

Total 18 7 38

76 28 2 0 0 15 184 6210 3.0TD: positive test doseDP: dural punctureVP: vascular punctureAB: abandoned blockFB: failed blockC: cardiovascular R: respiratoryN: neurological

NO significant complications in caudal group!

93% of caudal blocks placed without technical aids or imaging

3% with ultrasound guidance

Adverse Events and

Complications

Summary

Caudal anesthesia and analgesia is:• An easy technique to supplement general anesthesia• Requires few resources• Easy to learn• Provides several hours of postoperative analgesia• Is overall a very safe analgesic technique

Thank You Question

s?