Regional Anesthesia In The Emergency Department

Educational Objectives

The goal of this program is to improve pain management in the emergency department using regional anesthesia. After hearing and assimilating this program, the clinician will be better able to:

1. Assess the benefits and drawbacks of regional anesthesia and intravenous sedation in the emergency department.
2. Utilize common techniques for regional anesthesia in the emergency department.
3. Develop strategies for implementation of protocols for regional anesthesia in the emergency department based on availability of resources and personnel.
4. Summarize outcomes of experimental interventions to deliver regional anesthesia in the field.
5. Discuss potential issues with obtaining patient consent and training of ED providers.

Summary

Intravenous (IV) sedation: advantages — readily available; provides analgesia at multiple pain sites and does not require high level of technical expertise; disadvantages — fasting may be required to prevent aspiration; risk for oversedation requires preparation for pharmacologic reversal and airway management; morphine can cause histamine release and hypotension, and opioids can cause respiratory issues; staffing is needed to monitor for respiratory depression; multiple studies show that IV analgesics in the emergency department (ED) require longer length of stay than other analgesic modalities

Regional anesthesia: advantages — does not require fasting, and risks for oversedation, hypotension, and respiratory depression are minimal; disadvantages — additional training and expertise are required, and skills need to be practiced over time to avoid decrement; additional equipment is often required; nerve damage, local infection, or bleeding may occur; treatment team responsible for follow-up and management of complications often unclear; advantages, cont. — associated with shorter length of stay in the ED, need for fewer staff resources, lower cost and rate of hospital admission, and increase in patient satisfaction

Common Options

Intraarticular injections: commonly used with repositioning of dislocated joints; does not result in insensate limb, and should be considered when ability to monitor nerve function after relocation is important; not associated with increased risk for falls or positioning injuries; compared with other techniques, easier to perform and has a lower risk for nerve injury

Ankle dislocation: may improve patient comfort, decrease soft tissue swelling, and reduce risk for vascular compromise and articular damage; 2018 study showed that reduction was well tolerated without sedation, and time to reduction and severity of pain were similar between intraarticular injection and conscious sedation

Shoulder dislocation: decreases pain associated with relocation; 2002 study showed that, compared with sedation, rate of success in relocation was similar, but length of stay in the ED was shorter (75 vs 185 min) and cost associated with supplies and nursing care was lower ($0.52 vs $97)

Hematoma blocks: used for closed reductions of fractures of long bones; involves direct injection of anesthetic into hematoma; often require multiple injection sites, which may cause discomfort; potential complications associated with IV injection of local anesthetic and toxic dose of lidocaine (5 mg/kg without epinephrine or 7 mg/kg with epinephrine) should be considered

Intravenous regional anesthesia: common indications — reduction of distal fractures and repair of distal lacerations; advantages — allows for rapid recovery and reduces need for general anesthesia or deep conscious sedation; may not require fasting; monitoring — electrocardiography, blood pressure, pulse oximetry, and placement of 2 IV lines are required; maximal concentration and doses of lidocaine — 4 mg/kg in adults, with ≤40 mL in upper extremity and ≤60 mL in lower extremity; use of double cuff recommended to decrease risk for catastrophic effects of cuff failure

Pediatric patients: technique — involves minimal sedation and insertion of small-gauge peripheral IV into distal hand for gentle limb exsanguination; tourniquet is inflated, and 0.5% lidocaine (dose of 0.6-1 mL/kg) is given in Bier block over 60 sec; after 30 min, tourniquet is deflated; 1996 study — successful reduction in ED was reported in 98% of children with fractures of the upper extremity without need for anesthesia or peripheral nerve block; no adverse events were reported, and side effects were minimal; study of mini-dose in the ED — efficacy was reported if cuff was inflated for ≥15 min, and reduction of fracture in the ED was possible for the majority of patients

Considerations: low concentration of lidocaine (0.5%) is used; deflation of cuff may be catastrophic if bupivacaine is used; prolongation of analgesia with additives is usually unnecessary

Digital nerve block: performed on fingers or toes and provides several hours of analgesia; small dose of local anesthetic is usually used, and a long-acting local anesthetic is recommended if long duration of pain control is needed; effect of duration prolongation with use of epinephrine is usually minimal with long-acting local anesthetic; advantages — versatile, easy to perform, may prevent injury to the pleura or vessels of the neck and weakness or numbness of the chest and arm that are associated with nerve blocks in the proximal brachial plexus; use of ultrasonography for nerve blocks in the wrist and forearm may be considered

Education, Needs, and Considerations

Benefits of regional anesthesia in the ED: decreased risk for respiratory depression and delirium; better coherence and cooperation of the patient may allow provider to perform serial examinations, collect medical history, and obtain consent for other procedures; may improve stress and inflammatory response, which may lead to less coagulopathy, multiorgan dysfunction, and catabolism; reducing acute pain may help decrease subsequent posttraumatic stress syndrome

2016 survey of academic institutions with residency training programs in emergency medicine: indications for ultrasonography-guided regional nerve blocks — pain management for fractures was most common, followed by laceration repair, reduction of dislocation, drainage of abscesses, and removal of foreign bodies; technique — ≈84% of institutions performed regional anesthesia in ED; forearm nerve block was most common, followed by nerve blocks of the femoral nerve, posterior tibial nerve, fascia iliaca, and interscalene

Needs: interest and motivation of providers and staff, training of providers, assessment program for equipment, including ultrasonography, nerve stimulator, needles, local anesthetic, sedation, and immediate availability of lipid emulsion therapy for treatment of local anesthetic systemic toxicity

Considerations: risk for compartment syndrome, less availability of staff and equipment in the ED compared to the operating room (OR), and possible need to limit sedation because assistance may not be available if oversedation occurs; sympathectomy in setting of hypovolemia may result in profound hypotension; preexisting nerve injury may complicate neurologic findings after administration of nerve block; patients may not be fasted, and monitoring ability may be limited; pain may be multifactorial; patients may have received analgesics prior to arrival, which increases risk for sedation after local anesthesia; consent may be difficult to obtain in patient with severe pain who has taken analgesics

Compartment syndrome

Causes: risk is highest with fractures of the proximal tibia (6-10%; accounts for approximately one-third of all cases); other causes include crush or reperfusion injury, strenuous exercise, arterial punctures, circumferential dressings that are too tight, circumferential burns, and snake bites

Symptoms: “5 P’s” (pain, pallor, paresthesia, pulselessness, and paralysis, and sometimes poikilothermia) indicate distal signs of poor perfusion; other symptoms may include edema and swelling, pain to passive compartment stretch, and elevated compartment pressures; however, symptoms have a low positive predictive value and high negative predictive value; measurement of compartment pressure may be only reliable diagnostic tool

Physical examination: pain out of proportion to examination and pale or bluish limb increase index of suspicion; pulse and temperature of limb should be assessed; changes in pressure within the compartment should be measured, and tissue gradient of <30 mm Hg between tissue and diastolic blood pressure increases suspicion

Management: emergent fasciotomy ≤6 hr from onset of ischemia is important to prevent severe and permanent nerve injury; myonecrosis, rhabdomyolysis, myoglobinuria, acute tubular necrosis, hyperkalemia, and death can occur if not treated promptly

Regional anesthesia: minimal evidence to show that it masks compartment syndrome and may help identify early onset; avoidance of dense epidural analgesia may be considered in patients at high risk because some evidence suggests delay in diagnosis; close communication between anesthesia and orthopedic teams and assessment of risk for compartment syndrome are important; baseline neurologic examination is beneficial for identifying onset of deficit after nerve block; close monitoring after placement of regional anesthesia block is important; short-acting or dilute local anesthetics or alternative analgesic modalities may be considered in high-risk patients

Recommended provider: varies among practice setting; point-counterpoint article in 2019 debated whether specialists in pain management should help train non-anesthesia specialists outside of the OR; resources for performing procedures are available online, but provider may not know risks or alternatives for procedures even after using these; therefore, anesthesiologists can provide context to ensure procedures are performed safely

Orthopedic nurses: 2008 paper described initiative to train orthopedic nurses to perform fascia iliaca nerve blocks; creation of physician extender improved patient access to effective pain control

Paramedics: study from Germany that provided self-directed educational material with one-day didactic and simulation course with an anesthesiologist showed that patients who received fascia iliaca block from paramedic had lower levels of pain and requirements for morphine and antiemetics than patients who did not, although differences diminished by 120 min; however, differences may be more pronounced with long-acting anesthetic (lidocaine used in trial), and landmark-based technique may be difficult to perform in a moving ambulance

Clinical relevance of regional anesthesia in the field: older adults often have multiple comorbidities and may require medical clearance prior to surgery, which can be time-consuming; severe pain may require high doses of opioids, and older patients may have contraindications to alternative analgesics; opioids are also associated with complications, eg, delirium

Hip fractures: ultrasonography-guided approaches are most common, but nerve stimulation may be considered

Femoral nerve block: does not cover obturator, sciatic, or lateral femoral cutaneous nerve, and provider should discuss with patients about limitations and expectations for pain management (reduction, not elimination, of pain that is managed with lower doses of opioids); difficult to perform in obese patients and patients with previous vascular surgery; associated with motor weakness of the quadriceps muscle, which increases risk for falls

Fascia iliaca block: targets femoral, lateral femoral cutaneous, and obturator nerves; intensity of analgesia may be lower than with femoral nerve block; several approaches have been described; advantages — cephalad location may be good for placement of catheter to provide postoperative analgesia

Continuous femoral nerve catheter: considerations — may need to be removed for surgery, but may benefit patients who need to wait for medical clearance or availability of the OR prior to surgery; advantages — easy, can be used quickly, low risk for contamination, and may be safer than needle techniques for providers who have minimal experience; benefits — 2018 review of 31 trials showed that regional anesthesia was associated with reduction in pain scores of 3.4 points (on 10-point scale) 30 min after placement of the nerve block; decreased incidence of pneumonia, time to mobilization after surgery, cost, and opioid consumption; and increased patient satisfaction

Uptake for hip fractures: 2012 study of EDs in the United States showed that 33% ever perform and 6% often or almost always perform regional anesthesia; 2009 study from United Kingdom showed that 55% of physicians in the ED routinely used regional anesthesia

Risks: femoral nerve blocks and catheters are associated with increased risk for falls; nerve catheters can become dislodged or lead to bleeding or erythema; service for pain management can be helpful for management of complications

Headaches: rationale — drugs used to manage migraines in the ED require IV administration, have potential side effects, and are subject to shortages, and opioids have shortcomings and contraindications; sphenopalatine ganglion nerve block — retrospective case series of patients with acute migraine headache showed resolution at 15 min, 2 hr, and 24 hr in >70% of patients; may also be helpful for patients with postdural puncture headaches; occipital nerve block — landmark-based technique with low requirement for local anesthetic; risk for complications is low, but injection site is in close proximity to blood vessels; hair loss at injection site may occur; randomized study of 60 patients showed improvement in symptoms of migraine headache compared with patients who received placebo or IV therapy

Rib fractures: rationale — high morbidity associated with poor pain control, which may increase risk for needing intubation; opioids may be associated with sedation and respiratory depression; erector spinae plane block — provides large area of coverage and may provide utility in treatment of pain associated with spine fractures; catheters can be utilized; considerations for selection of block — severity of injury and requirements for oxygen and opioids

Issues with obtainment of consent: many patients in ED are unable to choose hospital or health care provider; capacity for decision-making may be diminished by opioids, inebriation, or pain; time constraints with treatment of patients in the ED may be an issue; patient autonomy and well-being need to be balanced with patients who are unconscious or have diminished decision-making capacity; should be approached as a shared decision-making process between provider and patient, and visual guides may help to improve patient comprehension

Training of ED providers: study that surveyed ED residency training programs about educational modalities used to teach ultrasonography-guided nerve blocks showed that didactic sessions were used for 67%, online resources for 54%, and supervised practice on real patients for 48%, and 19% of programs reported collaborating with other specialties; 2017 study found that 45% of ultrasonography directors in the ED reported feeling comfortable with current level of knowledge and techniques for ultrasonography-guided regional anesthesia; practical difficulties — include lack of ability to teach techniques, training, follow-up, standardized credentialing process, equipment, rescue drugs, and adequate support staff

Readings

Alhelail M et al. Comparison of bupivacaine and lidocaine with epinephrine for digital nerve blocks. Emerg Med J. 2009;26(5):347-350; Amini R et al. Ultrasound-guided nerve blocks in emergency medicine practice. J Ultrasound Med. 2016 Apr;35(4):731-6; Chua ISY et al. Intravenous regional anaesthesia (Bier’s block) for pediatric forearm fractures in a pediatric emergency department-Experience from 2003 to 2014. Injury. 2017 Dec;48(12):2784-2787; Driscoll EB et al. Regional anesthesia or patient-controlled analgesia and compartment syndrome in orthopedic surgical procedures: a systematic review. Local Reg Anesth. 2016 Oct 6;9:65-81; Gadsden J, Warlick A. Regional anesthesia for the trauma patient: improving patient outcomes. Local Reg Anesth. 2015;8:45-55; Kreutziger J et al. Comparison of interscalene block, general anesthesia, and intravenous analgesia for out-patient shoulder reduction. J Anesth. 2019;33(2):279-286; Mehta D et al. The effect of regional anesthetic sphenopalatine ganglion block on self-reported pain in patients with status migrainosus. Headache. 2019;59(1):69-76; Pasquier M et al. Fascia iliaca block in the emergency department for hip fracture: a randomized, controlled, double-blind trial. BMC Geriatr. 2019;19(1):180; Skjold C et al. Pre-operative femoral nerve block for hip fracture-A systematic review with meta-analysis. Acta Anaesthesiol Scand. 2020;64(1):23-33; Wilson C. Feeling blocked? Another pain management tool in the emergency department. Ann Emerg Med. 2018 Aug;72(2):120-126.

Disclosures

For this program, members of the faculty and planning committees reported nothing to disclose. In his lecture, Dr. Schroeder discussed the off-label or investigational use of a therapy, product, or device.

Acknowledgements

Due to the COVID-19 pandemic, Dr. Schroeder was recorded using teleconference software. The Audio Digest Foundation thanks the speakers and sponsors for their cooperation in the production of this program.

CME/CE INFO

Accreditation:

The Audio- Digest Foundation is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.

The Audio- Digest Foundation designates this enduring material for a maximum of 0 AMA PRA Category 1 Credits™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

Audio Digest Foundation is accredited as a provider of continuing nursing education by the American Nurses Credentialing Center's (ANCC's) Commission on Accreditation. Audio Digest Foundation designates this activity for 0 CE contact hours.

Lecture ID:

AN624701

Expiration:

This CME course qualifies for AMA PRA Category 1 Credits™ for 3 years from the date of publication.

Instructions:

To earn CME/CE credit for this course, you must complete all the following components in the order recommended: (1) Review introductory course content, including Educational Objectives and Faculty/Planner Disclosures; (2) Listen to the audio program and review accompanying learning materials; (3) Complete posttest (only after completing Step 2) and earn a passing score of at least 80%. Taking the course Pretest and completing the Evaluation Survey are strongly recommended (but not mandatory) components of completing this CME/CE course.

Estimated time to complete this CME/CE course:

Approximately 2x the length of the recorded lecture to account for time spent studying accompanying learning materials and completing tests.