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Peripheral nerve block and rebound pain: literature review

Abstract

Background and objectives:

To investigate, describe, and assess the phenomenon of “rebound pain” as a clinically relevant problem in anesthetic practice.

Content:

The phenomenon of “rebound pain” has been demonstrated and described as a very severe pain, which occurs after a peripheral nerve block resolution with the recovery of sensitivity. The incidence of rebound pain is unknown. Usually, it occurs between 12 and 24 hours after surgery and, adversely affecting sleep quality. It is not yet possible to establish a mechanism as a definitive cause or trigger factor of rebound pain. Studies suggest that rebound pain is a side effect of peripheral nerve blocks, despite their effectiveness in pain control. Currently, the extent and clinical significance of rebound pain cannot be well determined due to the lack of large prospective studies.

Conclusion:

Rebound pain assessment should always be considered in clinical practice, as it is not a rare side effect of peripheral nerve blocks. There are still many challenging questions to be answered about rebound pain, so large prospective studies are needed to address the issue. For prevention, the use of peripheral nerve block techniques that avoid nerve damage and adequate perioperative analgesia associated with patient education on the early administration of analgesics, even during the period of analgesia provided by peripheral nerve block, is recommended. A better understanding of the “rebound pain” phenomenon, its pathophysiology, associated risk factors, and long-term consequences may help in developing more effective preventive strategies.

KEYWORDS
Nerve block; Peripheral nerves; Rebound effect; Postoperative pain

Resumo

Justificativa e objetivos:

Investigar, descrever e avaliar o fenômeno da “dor rebote” como um problema clinicamente relevante na prática anestésica.

Conteúdo:

O fenômeno da “dor rebote” foi demonstrado e descrito como uma dor muito intensa que ocorre após a resolução do bloqueio de nervo periférico com o retorno da sensibilidade. A incidência de dor rebote é desconhecida. Normalmente ela ocorre entre 12 a 24 horas após a cirurgia e afeta negativamente a qualidade do sono. Ainda não é possível estabelecer um mecanismo como causa definitiva ou fator desencadeante da dor rebote. Estudos sugerem que a dor rebote seja um efeito colateral dos bloqueios de nervos periféricos, apesar destes terem eficácia no controle álgico. Atualmente, a extensão e a significância clínica da dor rebote não podem ser bem determinadas, devido à falta de grandes estudos prospectivos.

Conclusão:

A avaliação da dor rebote deve ser sempre considerada na prática clínica, pois não é um efeito colateral raro dos bloqueios de nervo periféricos. Ainda existem muitas questões desafiadoras a serem respondidas sobre a dor rebote, portanto fazem-se necessários amplos estudos prospectivos sobre a temática. Para a sua prevenção recomenda-se o uso de técnicas de bloqueio de nervo periférico que evitem a lesão do nervo e uma adequada analgesia perioperatória associada à orientação do paciente sobre a administração precoce de analgésicos mesmo na vigência da analgesia proporcionada pelo bloqueio de nervo periférico. A melhor compreensão do fenômeno “dor rebote”, sua fisiopatologia, seus fatores de risco associados e suas consequências em longo prazo poderá ajudar na elaboração de estratégias preventivas mais eficazes.

PALAVRAS-CHAVE
Bloqueio nervoso; Nervos periféricos; Efeito rebote; Dor pós-operatória

Introduction

More than 80% of patients undergoing surgical procedures have acute postoperative pain and approximately 75% of them report moderate to severe pain.11 Gan TJ, Habib AS, Miller TE, et al. Incidence, patient satisfaction, and perceptions of post-surgical pain: results from a US national survey. Curr Med Res Opin. 2014;30:149-60. The appropriate treatment of acute postoperative pain is associated with better clinical outcomes,22 Apfelbaum JL, Chen C, Mehta SS, et al. Postoperative pain experience: results from a national survey suggest postoperative pain continues to be undermanaged. Anesth Analg. 2003;97:534-40. while inadequate pain control may negatively impact patients’ postoperative experience.

Orthopedic procedures are associated with severe postoperative pain33 Gramke HF, de Rijke JM, van Kleef M, et al. Predictive factors of postoperative pain after day-case surgery. Clin J Pain. 2009;25:455-60. and an adequate postoperative pain control improves the patient's ability to participate in rehabilitation therapy due to the greater range of motion, which contributes to a better experience perceived by the patient postoperatively.44 Grant SA, Nielsen KC, Greengrass RA, et al. Continuous peripheral nerve block for ambulatory surgery. Reg Anesth Pain Med. 2001;26:209-14.

Peripheral nerve blocks (PNBs) are increasingly used in orthopedic surgery, since the benefits include long-lasting analgesic effects and a high level of safety, as it is well documented in elective foot, knee, and ankle surgeries.55 Court-Brown CM, McBirnie J, Wilson G. Adult ankle fractures - an increasing problem? Acta Orthop Scand. 1998;69:43-7. Regional anesthesia, particularly PNB, has the benefits of muscle relaxation and postoperative analgesia, allowing good control of postoperative pain and early hospital discharge.66 Joshi G, Gandhi K, Shah N, et al. Peripheral nerve blocks in the management of postoperative pain: challenges and opportunities. J Clin Anesth. 2016;35:524-9.

Although general anesthesia may be used in orthopedic surgeries, the use of regional anesthesia techniques has other additional benefits, such as less airway management, less postoperative nausea and vomiting, less stay in the Post-anesthesia Care Unite (PACU), less need for PACU interventions,77 Oh JH, Kim WS, Kim JY, et al. Continuous intralesional infusion combined with interscalene block was effective for postoperative analgesia after arthroscopic shoulder surgery. J Shoulder Elbow Surg. 2007;16:295-9.,88 Egol KA, Soojian MG, Walsh M, et al. Regional anesthesia improves outcome after distal radius fracture fixation over general anesthesia. J Orthop Trauma. 2012;26:545-9. and fewer opioid-related side effects such as pruritus and respiratory depression.44 Grant SA, Nielsen KC, Greengrass RA, et al. Continuous peripheral nerve block for ambulatory surgery. Reg Anesth Pain Med. 2001;26:209-14.,99 Richman JM, Liu SS, Courpas G, et al. Does continuous peripheral nerve block provide superior pain control to opioids? A meta-analysis. Anesth Analg. 2006;102:248-57.

Despite the success of regional anesthesia, several studies have demonstrated the occurrence of the phenomenon known as “rebound pain” as soon as the original blockade disappears.66 Joshi G, Gandhi K, Shah N, et al. Peripheral nerve blocks in the management of postoperative pain: challenges and opportunities. J Clin Anesth. 2016;35:524-9.,1010 DeMarco JR, Componovo R, Barfield WR, et al. Efficacy of augmenting a subacromial continuous-infusion pump with a preoperative interscalene block in outpatient arthroscopic shoulder surgery: a prospective, randomized, blinded, and placebo-controlled study. Arthroscopy. 2011;27:603-10.

11 Williams BA, Bottegal MT, Kentor ML, et al. Rebound pain scores as a function of femoral nerve block duration after anterior cruciate ligament reconstruction: retrospective analysis of a prospective, randomized clinical trial. Reg Anesth Pain Med. 2007;32:186-92.
-1212 Goldstein RY, Montero N, Jain SK, et al. Efficacy of popliteal block in postoperative pain control after ankle fracture fixation: a prospective randomized study. J Orthop Trauma. 2012;26:557-61. Although rebound pain occurs in a wide variety of surgeries1313 Janda A, Lydic R, Welch KB, et al. Thermal hyperalgesia after sciatic nerve block in rat is transient and clinically insignificant. Reg Anesth Pain Med. 2013;38:151-4.,1414 Kolarczyk LM, Williams BA. Transient heat hyperalgesia during resolution of ropivacaine sciatic nerve block in the rat. Reg Anesth Pain Med. 2011;36:220-4. and the phenomenon is well recognized, all studies have several methodological limitations that make it impossible to determine its clinical significance.

The occurrence of rebound pain may outweigh the benefits of PNBs and represent a clinically relevant problem. A better understanding of the rebound pain profile may allow the identification of at-risk patients and the development of prevention strategies. Given the lack of consistent data in the literature, this article proposes to evaluate the current available literature and the clinical relevance of the rebound pain phenomenon.

Methods

A literature search was performed on PubMed database in December 2017. The search terms used were Rebound AND Pain AND Nerve Block, and 28 results were obtained. Restricting the search to articles published in the last five years yielded 22 results, all of which were written in English. After reading the abstracts of the 22 articles, 19 articles addressing the topic under analysis were selected. In addition to the articles selected from the research, 31 articles referenced in them were also consulted. The analysis included 50 articles that addressed the occurrence of the rebound pain phenomenon in various types of surgeries, whose procedures were performed both in hospital and outpatient clinic.

Development

Definition

Rebound pain is defined as the quantifiable difference in pain scores when a PNB is working versus the acute pain found when the blockade stops working.1111 Williams BA, Bottegal MT, Kentor ML, et al. Rebound pain scores as a function of femoral nerve block duration after anterior cruciate ligament reconstruction: retrospective analysis of a prospective, randomized clinical trial. Reg Anesth Pain Med. 2007;32:186-92.,1515 Williams BA. Forecast for perineural analgesia procedures for ambulatory surgery of the knee, foot, and ankle: applying patient-centered paradigm shifts. Int Anesthesiol Clin. 2012;50:126-42. The rebound pain phenomenon has been demonstrated and described by many authors as a very severe pain that occurs with the return of sensitivity after the PNB resolution.66 Joshi G, Gandhi K, Shah N, et al. Peripheral nerve blocks in the management of postoperative pain: challenges and opportunities. J Clin Anesth. 2016;35:524-9.,1010 DeMarco JR, Componovo R, Barfield WR, et al. Efficacy of augmenting a subacromial continuous-infusion pump with a preoperative interscalene block in outpatient arthroscopic shoulder surgery: a prospective, randomized, blinded, and placebo-controlled study. Arthroscopy. 2011;27:603-10.

11 Williams BA, Bottegal MT, Kentor ML, et al. Rebound pain scores as a function of femoral nerve block duration after anterior cruciate ligament reconstruction: retrospective analysis of a prospective, randomized clinical trial. Reg Anesth Pain Med. 2007;32:186-92.
-1212 Goldstein RY, Montero N, Jain SK, et al. Efficacy of popliteal block in postoperative pain control after ankle fracture fixation: a prospective randomized study. J Orthop Trauma. 2012;26:557-61. Other authors describe it as “a poorly described entity, commonly defined as a dramatic increase in pain once regional anesthesia has dissipated”.1616 Galos DK, Taormina DP, Crespo A, et al. Does brachial plexus blockade result in improved pain scores after distal radius fracture fixation? A randomized trial. Clin Orthop Relat Res. 2016;474:1247-54.

Incidence

Due to the scarcity of experimental and clinical studies, the incidence of rebound pain phenomenon is still poorly documented. Nevertheless, its occurrence has been increasingly reported by researchers.

A meta-analysis evaluating the analgesic effect of a single-injection interscalene block for shoulder surgery showed that patients who received interscalene block were more likely to have rebound pain compared with those who did not receive the same blockade.1717 Abdallah FW, Halpern SH, Aoyama K, et al. Will the real benefits of single-shot interscalene block please stand up? A systematic review and meta-analysis. Anesth Analg. 2015;120:1114-29. A study with women undergoing breast cancer surgery showed that pectoral nerve block did not improve the quality of recovery score postoperatively when compared to pectoral nerve block with saline solution, and this was attributed to factors such as the occurrence of rebound pain.1818 Kamiya Y, Hasegawa M, Yoshida T, et al. Impact of pectoral nerve block on postoperative pain and quality of recovery in patients undergoing breast cancer surgery: a randomised controlled trial. Eur J Anaesthesiol. 2018;35:215-23. Regarding outpatient surgeries, a literature review showed that the incidence of rebound pain can reach up to 40% of patients after PNB resolution.1919 Lavand’homme P. Rebound pain after regional anesthesia in the ambulatory patient. Curr Opin Anaesthesiol. 2018;31:679-84.

Characteristics

Rebound pain presents with a disproportionately higher intensity in relation to the degree of the surgical stimulus.2020 Borgeat A. Single-shot interscalene block: light and shadows. Anesth Analg. 2015;120:995-6. It has a rapid onset and a limited duration of about 3-6 hours, occurs soon after PNB cessation, leads to sharp increases in pain scores with high rates of morphine consumption during the rebound period.2121 Sort R, Brorson S, Gogenur I, et al. Rebound pain following peripheral nerve block anaesthesia in acute ankle fracture surgery: an exploratory pilot study. Acta Anaesthesiol Scand. 2018;63:396-402.

Patients often describe rebound pain as a burning sensation that occurs mainly at night and negatively affects sleep quality.1111 Williams BA, Bottegal MT, Kentor ML, et al. Rebound pain scores as a function of femoral nerve block duration after anterior cruciate ligament reconstruction: retrospective analysis of a prospective, randomized clinical trial. Reg Anesth Pain Med. 2007;32:186-92.,1717 Abdallah FW, Halpern SH, Aoyama K, et al. Will the real benefits of single-shot interscalene block please stand up? A systematic review and meta-analysis. Anesth Analg. 2015;120:1114-29.,2222 Henningsen MJ, Sort R, Moller AM, et al. Peripheral nerve block in ankle fracture surgery: a qualitative study of patients’ experiences. Anaesthesia. 2018;73:49-58.,2323 Ganta A, Ding D, Fisher N, et al. Continuous infraclavicular brachial block versus single-shot nerve block for distal radius surgery: a prospective randomized control trial. J Orthop Trauma. 2018;32:22-6.

In a study of patients undergoing surgical fixation of ankle fractures, the patients receiving popliteal block experienced rebound pain within 12-24 hours postoperatively.1212 Goldstein RY, Montero N, Jain SK, et al. Efficacy of popliteal block in postoperative pain control after ankle fracture fixation: a prospective randomized study. J Orthop Trauma. 2012;26:557-61.,2424 Knight JB, Schott NJ, Kentor ML, et al. Neurotoxicity of common peripheral nerve block adjuvants. Curr Opin Anaesthesiol. 2015;28:598-604. The occurrence of rebound pain in this same postoperative period was also evidenced in patients undergoing surgical fixation of distal radius fracture who received brachial plexus block.1616 Galos DK, Taormina DP, Crespo A, et al. Does brachial plexus blockade result in improved pain scores after distal radius fracture fixation? A randomized trial. Clin Orthop Relat Res. 2016;474:1247-54.

Rebound pain can profoundly impact the patient's recovery experience and if the patient is unaware of this effect he may be subject to a worsening of the unrelieved pain with oral medications.2323 Ganta A, Ding D, Fisher N, et al. Continuous infraclavicular brachial block versus single-shot nerve block for distal radius surgery: a prospective randomized control trial. J Orthop Trauma. 2018;32:22-6. Thus, an increase in opioid consumption and emergency room visits, and a decrease in patient satisfaction may occur which minimizes the real benefits associated with regional anesthesia and increases the costs of postoperative care.1717 Abdallah FW, Halpern SH, Aoyama K, et al. Will the real benefits of single-shot interscalene block please stand up? A systematic review and meta-analysis. Anesth Analg. 2015;120:1114-29.,2020 Borgeat A. Single-shot interscalene block: light and shadows. Anesth Analg. 2015;120:995-6.,2222 Henningsen MJ, Sort R, Moller AM, et al. Peripheral nerve block in ankle fracture surgery: a qualitative study of patients’ experiences. Anaesthesia. 2018;73:49-58.

Risk factors

Factors that may be linked to rebound pain include age, type of surgery, surgical site, type of fracture, surgical regimen, type of PNB, nerve injury, local anesthetic concentration, insufficient postoperative analgesia, inadequate orientation of patients on pain control during the postoperative period, presence of preoperative pain, and psychological aspects.

Rebound pain is probably less problematic in elderly patients, while it is very severe in some patients, particularly younger patients.2121 Sort R, Brorson S, Gogenur I, et al. Rebound pain following peripheral nerve block anaesthesia in acute ankle fracture surgery: an exploratory pilot study. Acta Anaesthesiol Scand. 2018;63:396-402.

The surgical site and type of surgery may influence the occurrence of rebound pain, and studies have shown that certain techniques and surgeries are at greater risk of causing it. Pain severity was greater in shoulder surgery compared to complex knee surgery.1111 Williams BA, Bottegal MT, Kentor ML, et al. Rebound pain scores as a function of femoral nerve block duration after anterior cruciate ligament reconstruction: retrospective analysis of a prospective, randomized clinical trial. Reg Anesth Pain Med. 2007;32:186-92.

The use of PNBs for acute fracture surgery has not been thoroughly investigated, and acute fractures have an evolutionary course of postoperative pain that differs from that of elective procedures, which makes PNB less safe in this scenario.1919 Lavand’homme P. Rebound pain after regional anesthesia in the ambulatory patient. Curr Opin Anaesthesiol. 2018;31:679-84.

Rebound pain is particularly prevalent in patients undergoing outpatient surgery, which is believed to occur as a result of greater difficulty in having adequate pain control outside the hospital setting.1919 Lavand’homme P. Rebound pain after regional anesthesia in the ambulatory patient. Curr Opin Anaesthesiol. 2018;31:679-84.

The type of PNB used for anesthesia has not been objectively evaluated, but it is believed that neural damage caused by needle insertion and pressure trauma during local anesthetic injection may induce some perineural inflammation.1919 Lavand’homme P. Rebound pain after regional anesthesia in the ambulatory patient. Curr Opin Anaesthesiol. 2018;31:679-84. Local anesthetic concentrations can influence rebound pain intensity in vivo, but this factor has not been clinically studied.2424 Knight JB, Schott NJ, Kentor ML, et al. Neurotoxicity of common peripheral nerve block adjuvants. Curr Opin Anaesthesiol. 2015;28:598-604.

The administration of an analgesic drug 1-2 hours before the end of the analgesia provided by PNB may minimize the incidence of rebound pain. The lack of adequate patient education about the need for a pain therapy such as bridging analgesia, even in the absence of pain, may lead to ineffective pain control during the transition period for oral analgesics when the duration of analgesia provided by PNB ceases.1212 Goldstein RY, Montero N, Jain SK, et al. Efficacy of popliteal block in postoperative pain control after ankle fracture fixation: a prospective randomized study. J Orthop Trauma. 2012;26:557-61.

Patients’ expectations about PNB may interfere with postoperative pain perception and treatment because a concern for patients with nerve damage may lead to the development of falsely low pain tolerance.2222 Henningsen MJ, Sort R, Moller AM, et al. Peripheral nerve block in ankle fracture surgery: a qualitative study of patients’ experiences. Anaesthesia. 2018;73:49-58.

Rebound pain mechanisms

The pathophysiological mechanisms of rebound pain are complex and not fully understood. Rebound pain is characterized as a mechanical-surgical pain caused by unopposed nociceptive inputs, which are intensely received by the subject after PNB resolution.1414 Kolarczyk LM, Williams BA. Transient heat hyperalgesia during resolution of ropivacaine sciatic nerve block in the rat. Reg Anesth Pain Med. 2011;36:220-4. Some mechanisms of peripheral nerve injury due to mechanical and chemical effects from PNB in predisposed patients (those with severe preoperative pain and young patients) are still under debate by researchers.1919 Lavand’homme P. Rebound pain after regional anesthesia in the ambulatory patient. Curr Opin Anaesthesiol. 2018;31:679-84.

The intrinsic proinflammatory properties of local anesthetics, when associated with PNB nerve damage, may cause post-PNB hyperalgesia and neuropathic pain, and these manifestations may present as rebound pain.2525 Verlinde M, Hollmann MW, Stevens MF, et al. Local anesthetic-induced neurotoxicity. Int J Mol Sci. 2016;17:339.

Another theory proposes that while PNB prevents signal transduction, the retained nociceptive signal memories are amplified when the blockage finally wears off.1717 Abdallah FW, Halpern SH, Aoyama K, et al. Will the real benefits of single-shot interscalene block please stand up? A systematic review and meta-analysis. Anesth Analg. 2015;120:1114-29.

Post-PNB hyperalgesia theories have been tested in rat models with variable and inconclusive results; therefore, the clinical relevance of these findings in rebound pain pathophysiology is still uncertain. Rats undergoing sciatic nerve block with ropivacaine had transient hyperalgesia on thermal (but not mechanical) stimuli as the blockade dissipated (3 hours) compared with placebo, suggesting a potential action on a specific nerve fiber in rebound pain pathophysiology.1414 Kolarczyk LM, Williams BA. Transient heat hyperalgesia during resolution of ropivacaine sciatic nerve block in the rat. Reg Anesth Pain Med. 2011;36:220-4. Transient thermal hyperalgesia was also found in another study with rats after 4 hours of blockade.1313 Janda A, Lydic R, Welch KB, et al. Thermal hyperalgesia after sciatic nerve block in rat is transient and clinically insignificant. Reg Anesth Pain Med. 2013;38:151-4. Acute opioid-induced hyperalgesia is another hypothesis suggested.2626 Ochroch J, Williams BA. Rebound pain after a nerve block wears off. ASRA NEWS. 2018.

Rebound pain diagnosis

To better quantify rebound pain, Williams et al. proposed a standardized method of reporting rebound pain scores (Table 1).1111 Williams BA, Bottegal MT, Kentor ML, et al. Rebound pain scores as a function of femoral nerve block duration after anterior cruciate ligament reconstruction: retrospective analysis of a prospective, randomized clinical trial. Reg Anesth Pain Med. 2007;32:186-92.

Table 1
Rebound pain score. The score should be calculated by subtracting the lowest NS score within 12 hours before PNB resolution from the lowest NS score during the first 12 hours after PNB resolution.

Approaches for rebound pain prevention and treatment

Effective preventive strategies for rebound pain are challenging, as prevention should be done not only by the anesthesiologist, but also by the surgical team. It is necessary to educate the medical staff for effective measures to be taken. The effective prevention of rebound pain should aim at combining pharmacological and non-pharmacological approaches. The use of non-pharmacological approaches, such as informing and educating patients about post-PNB rebound pain and postoperative analgesia,1919 Lavand’homme P. Rebound pain after regional anesthesia in the ambulatory patient. Curr Opin Anaesthesiol. 2018;31:679-84. combined with early administration of analgesics, may allow patients to have a more effective postoperative pain control.1212 Goldstein RY, Montero N, Jain SK, et al. Efficacy of popliteal block in postoperative pain control after ankle fracture fixation: a prospective randomized study. J Orthop Trauma. 2012;26:557-61.

Pharmacological strategies

The supplementation of PNBs with perioperative multimodal analgesia protocols through the combination of analgesic drugs with distinct mechanisms of action is recommended.1717 Abdallah FW, Halpern SH, Aoyama K, et al. Will the real benefits of single-shot interscalene block please stand up? A systematic review and meta-analysis. Anesth Analg. 2015;120:1114-29. Drugs such as gabapentin, acetaminophen, ibuprofen, and dextromethorphan may be useful as rescue medications for rebound pain control and the use of these drugs may help maintain analgesia during the transitional period as PNB fades.2626 Ochroch J, Williams BA. Rebound pain after a nerve block wears off. ASRA NEWS. 2018.

It is recommended to avoid the use of hyperalgesic agents, such as volatile gases and short acting opioids, and to include the use of agents that modulate pain response, such as esmolol.2727 Malik OS, Kaye AD, Urman RD. Perioperative hyperalgesia and associated clinical factors. Curr Pain Headache Rep. 2017;21:4.,2828 Gelineau AM, King MR, Ladha KS, et al. Intraoperative esmolol as an adjunct for perioperative opioid and postoperative pain reduction: a systematic review, meta-analysis, and meta-regression. Anesth Analg. 2018;126:1035-49.

Use of adjuvants

The use of adjuvants in PNBs seems to play some role in decreasing rebound pain. Blockade efficacy may be enhanced by the addition of adjuvants to local anesthetics. Dexamethasone,2929 Huynh TM, Marret E, Bonnet F. Combination of dexamethasone and local anaesthetic solution in peripheral nerve blocks: a meta-analysis of randomised controlled trials. Eur J Anaesthesiol. 2015;32:751-8. betamethasone,3030 Watanabe K, Tokumine J, Yorozu T, et al. Particulate-steroid betamethasone added to ropivacaine in interscalene brachial plexus block for arthroscopic rotator cuff repair improves postoperative analgesia. BMC Anesthesiol. 2016;16:84. and alpha-2 agonists3131 El-Boghdadly K, Brull R, Sehmbi H, et al. Perineural dexmedetomidine Is more effective than clonidine when added to local anesthetic for supraclavicular brachial plexus block: a systematic review and meta-analysis. Anesth Analg. 2017;124:2008-20. have been reported to prolong the effects of brachial plexus block when added to local anesthetics. Non-systemic perineural dexamethasone when added to a clinical dose of bupivacaine may prevent reversible bupivacaine-induced neurotoxicity and rebound hyperalgesia after blockade resolution.3232 An K, Elkassabany NM, Liu J. Dexamethasone as adjuvant to bupivacaine prolongs the duration of thermal antinociception and prevents bupivacaine-induced rebound hyperalgesia via regional mechanism in a mouse sciatic nerve block model. PLoS One. 2015;10:e0123459. There are some studies suggesting that the systemic administration of dexamethasone may also prolong the effects of PNB.3333 Desmet M, Braems H, Reynvoet M, et al. I.V. and perineural dexamethasone are equivalent in increasing the analgesic duration of a single-shot interscalene block with ropivacaine for shoulder surgery: a prospective, randomized, placebo-controlled study. Br J Anaesth. 2013;111:445-52.,3434 Baeriswyl M, Kirkham KR, Jacot-Guillarmod A, et al. Efficacy of perineural vs systemic dexamethasone to prolong analgesia after peripheral nerve block: a systematic review and meta-analysis. Br J Anaesth. 2017;119:183-91.

Adjuvants not only prolong the duration of local anesthetic action, but it can also modulate PNB to decrease rebound pain through other unknown mechanisms. In blockades combined with general anesthesia aiming at analgesia alone, lower local anesthetic concentrations could be used in combination with perineural adjuvants.2424 Knight JB, Schott NJ, Kentor ML, et al. Neurotoxicity of common peripheral nerve block adjuvants. Curr Opin Anaesthesiol. 2015;28:598-604. A recent case series assessing the use of adjuvants in PNB showed that the combination of clonidine, buprenorphine, and dexamethasone with bupivacaine or ropivacaine was associated with reduced rebound pain severity. However, the authors of this study could not determine the optimal dose of adjuvants to achieve this benefit.2424 Knight JB, Schott NJ, Kentor ML, et al. Neurotoxicity of common peripheral nerve block adjuvants. Curr Opin Anaesthesiol. 2015;28:598-604.,3535 Williams BA, Ibinson JW, Mangione MP, et al. Research priorities regarding multimodal peripheral nerve blocks for postoperative analgesia and anesthesia based on hospital quality data extracted from over 1,300 cases (2011-2014). Pain Med. 2015;16:7-12.

Studies performed with radiculopathy patients have shown that the addition of sodium hyaluronate solution and carboxymethylcellulose solution to the conventional cocktail (corticosteroids, 1% lidocaine, 0.5% bupivacaine) in the selective nerve root block led to effective pain control within three days to two weeks,3636 Ko S, Chae S, Choi W, et al. Prolonged pain reducing effect of sodium hyaluronate-carboxymethyl cellulose solution in the selective nerve root block (SNRB) of lumbar radiculopathy: a prospective, double-blind, randomized controlled clinical trial. Spine J. 2018;19:578-86. and the rebound pain that occurs in these cases within 2-4 weeks after the conventional cocktail injection was reduced when hyaluronate was added to the conventional cocktail.3737 Ko SB, Vaccaro AR, Chang HJ, et al. An evaluation of the effectiveness of hyaluronidase in the selective nerve root block of radiculopathy: a double blind, controlled clinical trial. Asian Spine J. 2015;9:83-9.

Continuous peripheral nerve blocks

Rebound pain may be attenuated by prolonging the blockade duration, either by the continuous local anesthetic infusion technique via peripheral catheter or by the single injection technique. Continuous PNBs have an effect on analgesia due to decreased basal pain and inflammatory markers, in addition to interrupting the formation of neuronal memories associated with surgery.3838 Fisher A, Meller Y. Continuous postoperative regional analgesia by nerve sheath block for amputation surgery - a pilot study. Anesth Analg. 1991;72:300-3. In femoral nerve block knee surgery, the numeric rating scale was used to measure pain severity on a scale from 0 to 10 (0 = no pain, 10 = worst pain imaginable). It was observed that in order to reduce rebound pain scores by one unit, an additional 33 hours increase in PNB duration was required.1111 Williams BA, Bottegal MT, Kentor ML, et al. Rebound pain scores as a function of femoral nerve block duration after anterior cruciate ligament reconstruction: retrospective analysis of a prospective, randomized clinical trial. Reg Anesth Pain Med. 2007;32:186-92. The duration of analgesia must be significantly longer than that provided by a typical blockade to achieve a clinically significant reduction in rebound pain.1111 Williams BA, Bottegal MT, Kentor ML, et al. Rebound pain scores as a function of femoral nerve block duration after anterior cruciate ligament reconstruction: retrospective analysis of a prospective, randomized clinical trial. Reg Anesth Pain Med. 2007;32:186-92.,1717 Abdallah FW, Halpern SH, Aoyama K, et al. Will the real benefits of single-shot interscalene block please stand up? A systematic review and meta-analysis. Anesth Analg. 2015;120:1114-29. However, rehabilitation planning and patient preferences may limit the application of this technique by not allowing a prolonged period of motor block or decreased sensitivity.

In a meta-analysis, continuous PNBs improved postoperative analgesia and were associated with lower opioid-related complications compared with single-injection PNBs.3939 Chelly JE, Delaunay L, Williams B, et al. Outpatient lower extremity infusions. Best Pract Res Clin Anaesthesiol. 2002;16:311-20. Continuous PNB for pain control in ankle fracture surgery significantly reduced rebound pain and the need for opioid analgesia compared to single-injection PNB.4040 Ding DY, Manoli A, Galos DK, et al. Continuous popliteal sciatic nerve block versus single injection nerve block for ankle fracture surgery: a prospective randomized comparative trial. J Orthop Trauma. 2015;29:393-8. Continuous interscalene brachial plexus block also reduced postoperative pain and rebound pain.4141 Kim JH, Koh HJ, Kim DK, et al. Interscalene brachial plexus bolus block versus patient-controlled interscalene indwelling catheter analgesia for the first 48 hours after arthroscopic rotator cuff repair. J Shoulder Elbow Surg. 2018;27:1243-50.

The strategy of using continuous PNBs as a way to reduce the incidence of rebound pain is not yet a consensus in the literature. A prospective clinical trial with patients undergoing distal radius fracture fixation compared single-injection infraclavicular block with continuous infusion block. The use of continuous PNB showed no benefit and did not significantly reduce rebound pain or analgesic use within 8-72 hours postoperatively.2323 Ganta A, Ding D, Fisher N, et al. Continuous infraclavicular brachial block versus single-shot nerve block for distal radius surgery: a prospective randomized control trial. J Orthop Trauma. 2018;32:22-6.

Combined peripheral nerve blocks

Ultrasound-guided axillary nerve block combined with suprascapular nerve block reduced the rebound pain phenomenon after arthroscopic rotator cuff repair.4242 Lee JJ, Kim DY, Hwang JT, et al. Effect of ultrasonographically guided axillary nerve block combined with suprascapular nerve block in arthroscopic rotator cuff repair: a randomized controlled trial. Arthroscopy. 2014;30:906-14. The use of combined ultrasound-guided brachial plexus block and suprascapular nerve block reduced postoperative pain more effectively than single-injection block within 36 hours after arthroscopic cuff repair, in addition to decreasing the rebound pain phenomenon.4343 Lee JJ, Hwang JT, Kim DY, et al. Effects of arthroscopy-guided suprascapular nerve block combined with ultrasound-guided interscalene brachial plexus block for arthroscopic rotator cuff repair: a randomized controlled trial. Knee Surg Sports Traumatol Arthrosc. 2017;25:2121-8.

Other techniques

Comparing patients undergoing total knee arthroplasty (TKA) who received a continuous femoral nerve block and a single-injection sciatic nerve block or periarticular infiltrate and a postoperative continuous intra-articular infusion, the periarticular injections combined with an intra-articular catheter provided better pain control, no rebound pain, and decreased risk of motor block-related complications.4444 Stathellis A, Fitz W, Schnurr C, et al. Periarticular injections with continuous perfusion of local anaesthetics provide better pain relief and better function compared to femoral and sciatic blocks after TKA: a randomized clinical trial. Knee Surg Sports Traumatol Arthrosc. 2017;25:2702-7. In another study of TKA, the combination of intraoperative periarticular injection with preoperative femoral nerve block provided better pain management within the first 24 hours after surgery.4545 Youm YS, Cho SD, Cho HY, et al. Preemptive femoral nerve block could reduce the rebound pain after periarticular injection in total knee arthroplasty. J Arthroplasty. 2016;31:1722-6.

In primary shoulder arthroplasty, the patients treated with intraoperative soft tissue infiltration with injectable bupivacaine liposomal suspension required an equivalent amount of postoperative analgesics compared with patients treated with interscalene brachial plexus block, despite higher pain scores after 8 h in the group of patients who received PNB.4646 Namdari S, Nicholson T, Abboud J, et al. Randomized controlled trial of interscalene block compared with injectable liposomal bupivacaine in shoulder arthroplasty. J Bone Joint Surg Am. 2017;99:550-6.

Non-pharmacological strategies

Initial pain assessment and psychological follow-up of high-risk patients may be beneficial.1515 Williams BA. Forecast for perineural analgesia procedures for ambulatory surgery of the knee, foot, and ankle: applying patient-centered paradigm shifts. Int Anesthesiol Clin. 2012;50:126-42. Patient education and guidance may be the most useful short-term strategy and can be done during the preoperative assessment in which patients receive clarifications about PNB and rebound pain. Patients may be instructed regarding early analgesic use before regional anesthesia decline to maintain pain control, stay ahead of pain, while the PNB analgesia is still present. This strategy may allow patients to have more effective postoperative pain control.1616 Galos DK, Taormina DP, Crespo A, et al. Does brachial plexus blockade result in improved pain scores after distal radius fracture fixation? A randomized trial. Clin Orthop Relat Res. 2016;474:1247-54.

Clinical implications

PNB is likely to be effective, but rebound pain cannot be neglected as a side effect despite the appropriate use of a multimodal analgesic regimen. The long-term consequences of rebound pain in terms of functional recovery and persistent pain have not been thoroughly demonstrated and investigated in elective and emergency surgeries. However, according to the few published studies, the phenomenon does not appear to influence long-term patient recovery, both in terms of function1616 Galos DK, Taormina DP, Crespo A, et al. Does brachial plexus blockade result in improved pain scores after distal radius fracture fixation? A randomized trial. Clin Orthop Relat Res. 2016;474:1247-54. and pain.1717 Abdallah FW, Halpern SH, Aoyama K, et al. Will the real benefits of single-shot interscalene block please stand up? A systematic review and meta-analysis. Anesth Analg. 2015;120:1114-29.

Evidence suggests that the incidence of rebound pain may outweigh the benefits of PNBs in preventive analgesia, considering acute postoperative pain as an important risk factor for the development of persistent postoperative pain.4747 Fletcher D, Stamer UM, Pogatzki-Zahn E, et al. Chronic postsurgical pain in Europe: an observational study. Eur J Anaesthesiol. 2015;32:725-34. Thus, rebound pain may represent a clinically relevant problem and increase the use of health resources.

Studies report that despite the occurrence of rebound pain, patient satisfaction scores were high with the use of PNB, both as an anesthetic technique and in postoperative pain control.2121 Sort R, Brorson S, Gogenur I, et al. Rebound pain following peripheral nerve block anaesthesia in acute ankle fracture surgery: an exploratory pilot study. Acta Anaesthesiol Scand. 2018;63:396-402. A result also found in a review of outpatient surgery, in which regional anesthesia was associated with higher patient satisfaction compared with general anesthesia.4848 Liu SS, Strodtbeck WM, Richman JM, et al. A comparison of regional versus general anesthesia for ambulatory anesthesia: a meta-analysis of randomized controlled trials. Anesth Analg. 2005;101:1634-42. Many patients may have experienced a sense of relief by avoiding general anesthesia and this may have increased the satisfaction with PNB, as many patients fear general anesthesia.4949 Mavridou P, Dimitriou V, Manataki A, et al. Patient's anxiety and fear of anesthesia: effect of gender, age, education, and previous experience of anesthesia. A survey of 400 patients. J Anesth. 2013;27:104-8. On the other hand, patients may simply have considered the benefits of being awake during the procedure, absence of nausea, and many painless hours as “worth it”’ even if they experienced rebound pain for a few hours.2121 Sort R, Brorson S, Gogenur I, et al. Rebound pain following peripheral nerve block anaesthesia in acute ankle fracture surgery: an exploratory pilot study. Acta Anaesthesiol Scand. 2018;63:396-402.

Conclusion

Rebound pain is an entity of unknown etiology that interferes with the quality of the patient's postoperative recovery. Assessment of rebound pain should always be considered in clinical practice as it is not a rare side effect of PNBs.

For rebound pain prevention, we recommend the use of PNB techniques that prevent nerve damage and adequate perioperative analgesia associated with patient education about the early use of analgesics even in the presence of analgesia provided by PNB.

Despite the effort to better understand the rebound pain phenomenon and to identify at-risk patients, its management and prevention remain inappropriate.

The findings on this rebound pain phenomenon in the current literature are still scarce and the studies analyzed present several limitations regarding pain score measurements and data on postoperative analgesic medications, which hinders the analysis of the clinical implications of this event.

Extensive prospective studies and further studies aimed at better understanding the pathophysiology, prevalence, associated risk factors, and preventive methods are recommended. Currently, Sort et al. conducted a randomized study comparing PNBs with spinal anesthesia for ankle fracture surgery regarding postoperative pain profiles and quality of recovery. The secondary outcomes of this study include rebound pain.5050 Sort R, Brorson S, Gogenur I, et al. An ankle trial study protocol: a randomised trial comparing pain profiles after peripheral nerve block or spinal anaesthesia for ankle fracture surgery. BMJ Open. 2017;7:e016001.

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Publication Dates

  • Publication in this collection
    10 Feb 2020
  • Date of issue
    Nov-Dec 2019

History

  • Received
    13 Feb 2019
  • Accepted
    15 May 2019
Sociedade Brasileira de Anestesiologia R. Professor Alfredo Gomes, 36, 22251-080 Botafogo RJ Brasil, Tel: +55 21 2537-8100, Fax: +55 21 2537-8188 - Campinas - SP - Brazil
E-mail: bjan@sbahq.org