Block the pain: A nursing perspective on an opioid-sparing approach

Author(s): Jean Reinert, MS, BSN, RN

Understanding types of regional anesthesia helps ensure optimal patient outcomes.

Takeaways

  • Regional nerve blocks limit the use of opioids in patients after surgery and are being used more frequently.
  • Nursing considerations and interventions are required to prevent secondary injury because movement and sensation frequently are affected by regional nerve blocks.
  • Complications from nerve blocks found during the nursing assessment may vary depending on block type and location.

Current evidence-based practice supports using regional anesthesia (regional blocks) as a component of multimodal analgesia intervention when appropriate for the procedure and the patient. Regional blocks decrease the stress response that accompanies acute pain, helping to reduce postoperative use of opioid medications. They’re most commonly used for orthopedic, abdominal, and gyne­cologic surgeries; peripheral blocks are used for one extremity. Nursing care and assessment strategies can identify complications and improve outcomes, and patient education can enhance safety.

Opioid and regional block background

Opioids frequently are administered during anesthesia and postoperatively, and they’re prescribed at discharge. Their side effects include nausea, vomiting, impaired ventilation and apnea, confusion and fall, urinary retention, infrequent bowel movements, and paralytic ileus. The U.S. opioid crisis has influenced current surgical pain management guidelines. For example, the American Association of Nurse Anesthetists (AANA) recommends opioid-sparing approaches such as multimodal analgesia. When appropriate, regional anesthesia in the form of nerve blocks is gaining momentum as an opioid-sparing pain control intervention for surgery, although blocks carry their own risks such as hematoma. (See Regional block physiologic effects.)

Regional block physiologic effects

Regional blocks, used to produce anesthesia and analgesia, reduce pain perception by interfering with central and peripheral pain path- ways. These blocks prevent neurologic pain signals from communicating with the brain via sensory paths, but they also interrupt motor (efferent) pathways, leading to motor function loss. For example, a femoral nerve block will disrupt the impulses distally along the nerve’s course to the front of the thigh, resulting in diminished sensation and immobility from the anterior thigh to the knee.

Regional block medications

Various medications are used for regional blocks. Local anesthetics such as bupivacaine, bupivacaine liposome, and ropivacaine provide anesthesia and analgesia to specific areas. The concentration of the local anesthetic administered affects motor involvement, so the lowest amount of drug needed to achieve block should be used.

Dexmedetomidine can be added to the local anesthetic (off-label use) to enhance the block’s effects. According to Tripathi, for example, adding dexmedetomidine improves anesthesia quality and prolongs sensory and motor block and analgesia duration compared to clonidine when injected with bupivacaine as a supraclavicular brachial plex­us block. Dexmedetomidine’s mechanism of action is at the alpha-2 receptors of the spinal cord, ultimately decreasing the substance P peptide, which is one of the body’s chemicals responsible for nausea, vomiting, and pain. Hypo­tension and bradycardia are possible side effects when dexmedetomidine is added to regional anesthetics, particularly in patients with diabetes or hypovolemia, and those who are older than 65.

Nursing assessment

Your nursing assessment will vary depending on the type of regional block administered, but some common strategies are helpful. Assess for signs of seizures, anaphylaxis, and local anesthesia systemic toxicity, especially immediately after administration. For patients with no life-threatening complications, follow your hospital’s policy for postsurgical monitoring. Filson and colleagues suggest monitoring every 15 minutes for 1 hour, every 30 minutes for 2 hours, and then every hour for the first 4 hours and then at 4-hour intervals. If the patient’s vital signs are stable, then assess every 4 hours for 24 hours.

Evaluate the operative area’s sensory and motor function every 4 hours until the patient can completely move and feel the area. If possible, touch the skin of the affected area to assess for sensory function; for example, touch the skin with an alcohol wipe and ask if the patient feels coolness. Also ask if the patient feels numbness, tingling, or temperature changes in the affected area. Next, check the patient’s motor function against resistance (for example, assess dorsiflexion and plantar flexion for blocks in the lower extremity). Perform neurovascular assessments, such as peripheral pulses, capillary refill, and skin tem­perature, every 4 hours for the first 24 hours.

In addition, evaluate for the presence of hematoma (which may not become symptomatic for up to 6 hours after regional block administration) at the administration site every 4 hours for the first 24 hours. Block placement using ultrasound guidance reduces hematoma risk but doesn’t eliminate it. Patients who are morbidly obese are particularly susceptible to undiagnosed hematoma because of challenges in adequately identifying anatomic structures. Patients who receive anticoagulant therapy also are at high risk of a hematoma. Assess and investigate new pain onset anywhere near the block administration site, and don’t dismiss pain as an expected postoperative finding. Pain may not occur with a hema­toma, so also watch for motor function changes.

If the patient doesn’t display any neurovascular abnormalities and no hematoma occurs after 24 hours, perform assessments every 8 hours. A regional block worksheet or a section built into the electronic health record is recommended to organize and record assessments. (To view a sample regional block nursing assessment worksheet, click here.)

Specific regional blocks

Interscalene, femoral, adductor canal, and transversus abdominis plane (TAP) nerve blocks require specific nursing considerations related to their associated clinical implications. (See Nursing considerations.)

Nursing considerations

Your nursing assessment and considerations may vary depending on the type of regional nerve block administered.

Block type Affected body area Nursing considerations
Interscalene Upper extremity

• Protect upper extremity from injury, edema, and compartment syndrome by using a sling or immobilizer.

• Monitor peripheral circulation of the affected area.

• Instruct the patient to avoid using the affected extremity.

• Perform hourly assessments for 24 hours or until symptoms improve for patients with Horner syndrome, voice hoarseness, or inhibited diaphragm function.

• After symptoms resolve, assess the patient every 4 hours.

• Examine the patient’s eyes for differences in pupil size. The pupil on the affected side may be smaller than the other pupil, but both should be reactive to light.

• Maintain continuous pulse oximetry for patients with inhibited diaphragm function and provide an incentive spirometer.

• If the patient’s oxygen saturation level falls below 92%, anticipate starting oxygen while the cause is confirmed.

Femoral Lower extremity

• Be aware that patients who’ve had a femoral block are at increased fall risk due to quadriceps weakness.

• Assess motor and sensory function every 4 hours.
• Assess the patient’s ability to extend the knee against resistance before standing or walking.

• To deter the patient from getting out of bed without assistance, keep the call bell, urinal, and bedpan easily accessible.

Adductor canal Lower extremity

• Assess motor and sensory function every 4 hours.

• Assess the patient’s ability to extend the knee against resistance before standing or walking.

• Know that patients who’ve had an adductor canal nerve block should have minimal quadriceps weakness compared to those who’ve had a femoral nerve block, but they will still require walking assistance.

Transversus abdominis plane Abdomen

• Assess for leg weakness in patients prescribed an abdominal binder. Binders may cause compression and femoral nerve palsy.

• Evaluate the patient’s lower extremity strength bilaterally before ambulating.

Interscalene blocks

Shoulder surgery and frozen shoulder mobilization frequently includes an interscalene block for anesthesia and postprocedure analgesia. The block, guided by ultrasound and a nerve stimulator, is placed through the scalene muscles of the neck to reach the brachial plexus. The result includes loss of motor and sensory function to most of the upper extremity. Interscalene block complications—including Horner syndrome (in which the eye of the affected side is smaller and the eyelid droops), voice hoarseness, inability to sweat on one side of the face, and limited diaphragm movement on the surgical side—result from the anesthetic spreading to adjacent nerve tissue. Side effects are temporary and usually subside within 24 hours.

Femoral block and adductor canal block

Patients undergoing knee surgery benefit from either a femoral or adductor canal block for pain control. The adductor canal block primarily inhibits sensory function while preserving most of the femoral nerve motor segments. A femoral block inhibits both sensory and motor function, causing significant weakness to the quadriceps muscle. Both blocks inhibit pain, but patients receiving an adductor canal block can ambulate with assistance, whereas those who’ve received a femoral block usually are unable to walk the day of surgery, even with help.

TAP block

A TAP block involves the fascia surfaces of the abdominal wall. It inhibits abdominal wall sensory nerves derived from T7 to T11, which means patients can move their abdominal muscles but have limited sensation and pain to the area. TAP blocks are used for hysterectomies, cesarean sections, and colorectal surgeries. They’re also performed in the post­anes­thesia care unit if the patient’s pain control is inadequate. An unlikely but serious potential side effect is femoral nerve palsy, which may occur if the block spreads between the abdominal planes and affects the femoral nerve. Compression on the abdominal wall increases spread, so an abdominal binder should be used cautiously. If signs of compression are present, the binder should be removed.

Patient education

Patient education should begin preoperatively and continue through discharge. Essential education for patients discharged before regional anesthetics have worn off include how to protect the blocked area. Inform patients that regional blocks can last up to 72 hours, so they should anticipate continued numbness, tingling, and weakness. Instruct patients to use a sling or pillows under the upper extremity to avoid dangling, which can lead to edema. Because sensation is altered, patients should avoid activities such as cooking and grilling to prevent accidental burns. Remind patients with lower extremity blocks to be cautious when walking, and emphasize using appropriate orthopedic equipment, such as immobilizers, walkers, or crutches.

Explain that oral pain medication will resume when the patient begins regaining sensation and movement. Timing the introduction of oral medication is essential because waiting for full mobility and feeling to return may make pain control difficult. Adequate pain control can prevent patients from re­lying on opioids to manage discomfort. (For more patient education information, click here.)

Ensure good outcomes

To reduce the risk of opioid misuse, the AANA recommends multimodal analgesia, including regional blocks, for postoperative pain management. When you consider the location of the affected area and the physiologic changes produced by regional blocks, you can accurately assess patients’ neurologic function, anticipate complications, provide appropriate care, and confidently educate patients to ensure good outcomes.

Jean Reinert is a postanesthesia care unit nurse at St. Luke’s University Health Network, Anderson Campus in Easton, Pennsylvania, and a graduate assistant at Indiana University of Pennsylvania in Indiana, Pennsylvania.

References

American Association of Nurse Anesthetists. A Holistic Approach to Pain Management: Integrated, Multimodal, and Interdisciplinary treatment: Position Statement. July 2016. aana.com/docs/default-source/practice-aana-com-web-documents-(all)/a-holistic-approach-to-pain-management-integrated-multimodal-and-interdisciplinary-treatment.pdf

Burchill C, Anderson B, O’Connor PC. Exploration of nurse practices and attitudes related to postoperative vital signs. MedSurg Nurs. 2015;24(4):249-55.

Filson K, Atherholt C, Simoes M, et al. Post-operative vital signs: How often is too often? J Clin Oncol. 2018;36 (30 suppl):210.

Jaeger P, Koscielniak-Nielsen ZJ, Hilsted KL, Fabritius ML, Dahl JB. Adductor canal block with 10 mL versus 30 mL local anesthetics and quadriceps strength: A paired, blinded, randomized study in healthy volunteers. Reg Anesth Pain Med. 2015;40(5):553-8.

Kanagalingam S, Miller NR. Horner syndrome: Clinical perspectives. Eye Brain. 2015;7:35-46.

Koepke EJ, Manning EL, Miller TE, Ganesh A, Williams DGA, Manning MW. The rising tide of opioid use and abuse: The role of the anesthesiologist. Perioper Med. 2018;7:16.

Koniuch KL, Harris B, Buys MJ, Meier AW. Case report of a massive thigh hematoma after adductor canal block in a morbidly obese woman anticoagulated with apixaban. Case Rep Anesthesiol. 2018;2018:7653202. Published 2018 Aug 13.

Mian A, Chaudhry I, Huang R, Rizk E, Tubbs RS, Loukas M. Brachial plexus anesthesia: A review of the relevant anatomy, complications, and anatomical variations. Clin Anat. 2014;27(2):210-21.

Mistrova E, Kruzliak P, Chottova Dvorakova M. Role of substance P in the cardiovascular system. Neuropeptides. 2016;58:41-51.

Mudumbai SC, Kim TE, Howard SK, et al. Continuous adductor canal blocks are superior to continuous femoral nerve blocks in promoting early ambulation after TKA. Clin Orthop Relat Res. 2014;472(5):1377-83.

Oderda GM, Said Q, Evans RS, et al. Opioid-related adverse drug events in surgical hospitalizations: Impact on costs and length of stay. Ann Pharmacother. 2007;41(3):400-6.

Rasouli MR, Viscusi ER. Adductor canal block for knee surgeries: An emerging analgesic technique. Arch Bone Jt Surg. 2017;5(3):131-2.

Salaria ON, Kannan M, Kerner B, Goldman H. A rare complication of a TAP block performed after caesarean delivery. Case Rep Anesthesiol. 2017. ncbi.nlm.nih.gov/pmc/articles/PMC5682055

Scott-Warren VL, Sebastian J. Dexmedetomidine: Its use in intensive care medicine and anaesthesia. BJA Education. 2016;16(7):242-6.

Shah A, Hayes CJ, Martin BC. Characteristics of initial prescription episodes and likelihood of long-term opioid use—United States, 2006-2015. MMWR Morb Mortal Wkly Rep. 2017;66(10):265-9.

Shah VI, Upadhyay S, Shah K, et al. Risk of falling after femoral nerve block for total knee arthroplasty: Periprosthetic fractures—A serious concern. J Recent Adv Pain. 2017;3(3):125-30.

Tripathi A, Sharma K, Somvanshi M, Samal RL. A comparative study of clonidine and dexmedetomidine as an adjunct to bupivacaine in supraclavicular brachial plexus block. J Anaesthesiol Clin Pharmacol. 2016:32(3):344-8.

Waldinger R, Weinberg G, Gitman M. Local anesthetic toxicity in the geriatric population. Drugs Aging. 2020; 37(1):1-9.

Wardhan R, Chelly J. Recent advances in acute pain management: Understanding the mechanisms of acute pain, the prescription of opioids, and the role of multimodal pain therapy. F1000Res. 2017;6:2065.

LEAVE A REPLY

Please enter your comment!
Please enter your name here