- Email: [email protected]
Outpatient Continuous Interscalene Brachial Plexus Block in Cancer-Related Pain
Vol. 38 No. 4 October 2009
Journal of Pain and Symptom Management
629
Palliative Care Rounds
Outpatient Continuous Interscalene Brachial Plexus Block in Cancer-Related Pain Deans Buchanan, BSc, MBChB, MRCP, Emma Brown, BSc, MBChB, MRCP, FRCR, Fergus Millar, MBChB, FFARCSI, Fiona Mosgrove, BMSc, MBChB, Raj Bhat, MBBS, MS, FRCS(Ed), FRCS(Glas), FRCR, and Pamela Levack, MBChB, FRCP Departments of Palliative Medicine and Supportive Care (D.B., P.L.), Clinical Oncology (E.B., F.M.), Anaesthesia (F.M.), and Radiology (R.B.), Ninewells Hospital, Dundee, Scotland, United Kingdom
Abstract This case outlines the use of a continuous interscalene brachial plexus block to treat cancerrelated pain. Using an elastomeric device, the patient’s previously intractable pain was controlled and he was able to return home. Furthermore, the patient developed a pragmatic and effective method of balancing loss of power and sensation against pain control using the flow restrictor. This case illustrates the potential of an integrated approach to cancer pain management to obtain rapid pain relief in the acute hospital setting. J Pain Symptom Manage 2009;38:629e634. Ó 2009 U.S. Cancer Pain Relief Committee. Published by Elsevier Inc. All rights reserved. Key Words Interscalene block, cancer pain, elastomeric device, continuous peripheral nerve block
Introduction Regional anesthetic techniques are widely used for pain management in both malignant and nonmalignant conditions.1 Recent developments in portable infusion delivery devices have allowed the expansion of the role of nerve blockade.2 Interscalene brachial plexus block (ISB) is widely used to provide analgesia and anesthesia to the shoulder and proximal upper limb.3 It is usually considered within the postoperative setting and is associated with reduced pain, reduced opioid requirements, and reduced side effects.4 Complications can occur during insertion (although these are reduced
Address correspondence to: Deans Buchanan, BSc, MBChB, Roxburghe House, Royal Victoria Hospital, Jedburgh Road, Dundee DD1 1SP, Scotland, United Kingdom. E-mail: [email protected] Accepted for publication: December 10, 2008. Ó 2009 U.S. Cancer Pain Relief Committee Published by Elsevier Inc. All rights reserved.
by using ultrasound guidance5) and also as a result of the indwelling catheter. These complications can include brachial plexopathy, pneumothorax, local anesthetic reactions, arrhythmias, hemidiaphragmatic paralysis, and line-related infection.4 There is now increasing use of this technique in postoperative outpatients using elastomeric devices to provide continuous infusions of local anesthetic.6 Outpatient use has been shown to be acceptable to patients;7 provide potent analgesia with significantly less pain, opioid consumption, and opioid side effects as compared with placebo;8 and have a low complication rate.9 Peripheral nerve blockade in cancer-related pain must be considered within the context of goals of care, likely prognosis, and planned definitive treatments.1 ISB has been used in intractable cancer-related pain10 using a syringe driver, but the use of elastomeric devices has not been reported in this context. 0885-3924/09/$esee front matter doi:10.1016/j.jpainsymman.2008.11.012
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This case describes the use of an indwelling catheter and elastomeric device to provide continuous analgesia in a patient with renal cancer and a painful glenoid metastasis with associated fracture. The ISB was initially used as inpatient analgesia and subsequently provided outpatient analgesia.
Case History A 66-year-old gentleman diagnosed with a clear cell carcinoma of the left kidney underwent a left nephrectomy. After developing left shoulder pain, plain radiographs revealed a lytic lesion within the glenoid and an associated pathological fracture. Palliative radiotherapy was arranged and delivered to this area. Before commencing interferon chemotherapy, his pain increased and admission was required. It was agreed that interferon would be delayed until the situation could be improved. The patient was referred to the hospital palliative care team for pain control. Pain was maximal in the anterior shoulder, with no characteristics or clinical signs of neuropathic pain. Rest pain was scored as 5e7/10 on a numeric rating scale (NRS), and movement-related incident pain was rated as 8e10/10, lasting for four to five minutes after movement ceased. Range of movement of the shoulder was severely restricted and activities of daily living, such as dressing and eating, were disturbed. A collar and cuff sling had been tried to no benefit. The patient wished to retain full function and to be free of the pain with a low medication burden. He was particularly concerned about sedation as a side effect. Baseline analgesia consisted of a combination of paracetamol (acetaminophen) 1 g and codeine 60 mg three times daily, diclofenac 50 mg twice daily, and oxycodone immediate release 10 mg as required. Morphine had not been tolerated because of sedation and nausea. The submaximal frequency of dosing was related to the patient’s own concerns over toxicity and renal function. Codeine was discontinued, the paracetamol was increased to four times daily, and diclofenac was increased to three times daily. Oral
Vol. 38 No. 4 October 2009
hydromorphone slow-release was commenced at 2 mg twice daily, with 1.3 mg immediaterelease capsules as needed. The background hydromorphone was titrated against rest pain to 8 mg twice daily, reducing NRS to 3e4/10. Incident pain remained severe, and mild opioid toxicities of sedation and myoclonus were present. First-line breakthrough analgesia was changed to the shorter-acting opioid fentanyl (400 mcg) using transmuscosal delivery. Sedation remained a problem. Orthopedic and interventional radiology opinions were sought to consider definitive treatments (surgery, percutaneous cementoplasty, percutaneous radiofrequency ablation, or percutaneous embolization). A computed tomography (CT) scan of the affected shoulder was performed to allow detailed assessment. The anesthesia team was contacted to consider ISB plexus blockade to provide interim analgesia and facilitate opioid reduction. A 20G polyamide catheter was inserted using an 18G 50mm Tuohy needle (Pajunk, Geisingen, Germany) under ultrasound guidance. This was then attached to a 500 mL EasypumpÒ disposable ambulatory elastomeric infusion device (Braun, Melsungen, Germany). Elastomeric infusion devices consist of a distendable bulb housed within a protective shell attached to delivery tubing and a bacterial filter.1 Initial insertion and test dosing showed good placement and effect. Ropivacaine 0.2% was delivered at a restricted flow rate of 5 mL/hour. Pain at rest was mostly abolished, with the exception of an occasional ‘‘ache’’ (1e2/10) and incident pain was reduced to 3e4/10, with a dramatic increase in the range of movement. Activities of daily living were resumed. The initial catheter was placed without subcutaneous tunneling and became displaced after 24 hours. The pain profile returned to baseline and a further procedure was carried out. The second catheter was tunneled subcutaneously and the patient’s own ‘‘waist bag’’ (a small travel bag secured around the waist with a pouch at the front) was used to house the heavier weight of the reservoir. The hydromorphone was reduced to 4 mg twice daily with no loss of pain control. Over the next 24 hours, the patient developed a technique for balancing the numbing side effects of the ropivacaine and the analgesia. Using the clamp, he was able to restrict the
Vol. 38 No. 4 October 2009
Interscalene Block for Cancer-Related Pain
flow when the numbness increased and release the flow when he felt early sensation of pain. This had the effect of prolonging the lifetime of each reservoir and placed some control back into the patient’s hands. CT imaging of the shoulder revealed a large lytic lesion in the scapula. This measured approximately 6 cm in maximum diameter and eroded the articular surface of the glenoid. There was a pathological fracture through the body of the scapula. Surgical options were limited to amputation. Radiological interventions were limited to embolization, with some risks. With the distribution of the lytic lesion outlined by CT, it was decided that further outpatient radiotherapy could be delivered using CT planning. The potential complications of the indwelling catheter and blockade were explained and the patient was allowed to return home. Breakthrough analgesia was provided as originally outlined and, in the event of complications, a plan of return was agreed. A date to return to change the reservoir was also arranged. On return, the patient described good pain control throughout the three days at home and reported that, by Day 2, he had been able to stop the flow of anesthetic completely. The catheter was reviewed: there were no signs of infection and it remained in the correct position. He was able to go home, this time with an elastomeric device primed and available for direct attachment if the pain returned. His hydromorphone was provided in 2 mg tablets to allow dose reduction if the pain remained controlled. A further review date was set to correspond to CT scan planning for further radiotherapy. At Day 10, he was reviewed and the pain remained under control, without the infusion being required. There were no visible signs of infection at the catheter site. The catheter was removed. Radiotherapy was delivered, with no complications, and pain remained controlled on 2 mg hydromorphone twice daily. After four weeks, despite some residual shoulder stiffness, the patient was able to discontinue all analgesics with no ongoing pain. Interferon therapy was eventually commenced and the patient remained under treatment four months after the interscalene block.
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Discussion Most of the cancer-related pains can be managed successfully using oral analgesia and noninvasive methods. However, for some patients, more complex interventions may be required to achieve control within an acceptable time frame and within a tolerable therapeutic window.11 Early intervention in selected patients can lead to improved quality of life.12 This needs to be placed firmly within the context of patients’ goals and clear understanding of both the limitations and possible complications of invasive techniques. This case highlights the importance of using invasive techniques to achieve pain relief in patients who have intractable pain or intolerable side effects from systemic analgesia. It also illustrates the potential of an integrated approach in cancer pain management to obtain rapid pain relief in the acute hospital setting. A wide range of peripheral nerves can be blocked to target different pains: interscalene block (shoulder and upper limb), intercostal block (chest wall) and lumbar or sacral plexus blocks (pelvis and lower limbs).1 Fischer outlines the two main utilities of peripheral nerve blockade in palliative medicine as short-term use (aiding diagnosis of the cause of the pain and acting as bridging analgesia to allow introduction of other therapies) and longer-term use in the treatment of pain resulting from peripheral nerve damage.1 Other therapies may include physiotherapy (within an analgesic window), surgery, radiological interventions, and oncological treatments. Newer techniques for pain control are becoming available but may require a period of radiological assessment and planning before they can be provided. Such techniques include cementoplasty,13 embolization,14 and radiofrequency ablation15 of painful bone metastases. In this case, these procedures were considered, but the breach in the articular surface of the shoulder joint was a contraindication to cementoplasty because of the risk of an intra-articular cement leak. Radiofrequency ablation was also inappropriate because of the lesion’s size and its proximity to the brachial plexus. Embolization was technically possible. The risks of embolization included increased pain post procedure (although
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nerve blockade would reduce this) but a risk of loss of joint architecture and reduction or loss of shoulder function. The pain relief in the medium term after embolization is also difficult to predict and there is only limited evidence available for its use in the palliative setting.16 The patient did not wish to pursue this procedure. With the enhanced information regarding location of the fracture and metastases, it was possible to provide further targeted external beam radiotherapy. If this had not been the case, then embolization may have been reconsidered. However, as the pain was unilateral, a further option for pain control was percutaneous anterolateral cordotomy.17 The patient was highly motivated and wished to obtain maximal analgesia and limb function with minimal side effects alongside a low tablet burden. In addition, it was important that he remained mobile and was able to be managed as an outpatient. Elastomeric devices are one type of disposable infusion pumps that have been developed over the last 25 years. Disposable pumps have been used in a variety of settings to provide hospital and community-based therapies, including chemotherapy, antimicrobials, opioid analgesia, and continuous regional anesthesia.18 Continuous peripheral nerve blockade, including ISB blocks, are used predominately in the surgical setting.4 They were initially used in the inpatient population, but the ability to deliver infusions using elastomeric devices has allowed this to be extended to outpatient use. In the adult postoperative setting, short-term outpatient infusions have been shown to be safe, effective, and acceptable to patients.2,8 Furthermore, Ludot et al. described the use of outpatient elastomeric devices for continuous peripheral nerve blockade in 47 children undergoing ankle or foot surgery.19 In this study, the parents provided ongoing surveillance for complications, with good analgesia, satisfaction, and quality of life observed in most of the cases.19 The elastomeric reservoir used in this case could accommodate a volume of 500 mL and the flow rate was set at 5 mL/hour. As such, approximately 100 hours (four days) of drug delivery was available. The patient’s own ingenuity produced a situation in which the flow rate of ropivicaine was managed using the on/ off valve to balance loss-of-arm sensation and
Vol. 38 No. 4 October 2009
level of analgesia. This also had the effect of extending the time over which the drug would be delivered. It is of note that patient-controlled continuous interscalene regional anesthesia has been previously documented, with patient education regarding ‘‘top-up’’ boluses and clamping being provided to allow flexible use; in the group receiving perineural infusion of the ropivicaine compared with placebo, this randomized, double-blind, placebo-controlled trial found less pain, reduced opioid use, had fewer side effects, reduced sleep disturbance, and had low levels of complications.8 Interscalene blocks were described as early as 1919, but the approach was refined over subsequent years. A detailed description of the block is provided by Bollini.4 ISB targets the most superior and proximal components of the brachial plexus, producing regional anesthesia in the shoulder and upper limb. The procedure previously relied on techniques to assess needle proximity to the target nerve (nerve stimulation or test dosing). The introduction of ultrasound guidance allows direct visualization. The use of ultrasound appears to decrease the time required for placement of the block, reduce immediate complications, and improve block quality.5 It also may increase the acceptability of the procedure itself by avoiding the discomfort associated with nerve stimulation.9 Most of the published data describes the use of indwelling continuous nerve blocks over a short postoperative period of two to five days. Within this time frame, there are low levels of clinically observable infection. In one large multicenter study of 1416 patients with peripheral postsurgical nerve blocks (256 were ISB), only 3% had clinical signs of infection, but 28.7% had positive catheter-tip cultures after removal. Most of the cultures were positive for coagulase-negative staphylococcus (61%); some of these likely represent skin contaminants on removal.20 Other potential complications specific to ISB include neurovascular injury on insertion, inadvertent intravascular local anesthetic injection, pneumothorax, phrenic nerve palsy, transient hemidiaphragmatic paralysis (because of blockade of C3, 4, and 5 roots), Horner’s syndrome, and recurrent laryngeal palsy.3 It has been noted that these more serious complications are both rare and seldom permanent.9 Bryan et al. reviewed 147 consecutive ISB used in the outpatient setting and found no
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Interscalene Block for Cancer-Related Pain
episodes of neurovascular injury, infection, or anesthetic toxicity. The only insertion-related complication was a small self-resolving pneumothorax. Fourteen patients experienced minor adverse events, eight had inadequate analgesia, and four had catheters dislodged. No episodes of infection were reported.9 It is not clear for what duration catheters can safely remain in situ. In our own patient, the first catheter was in situ for only 24 hours until it became dislodged. The second catheter remained in situ, with no evidence of infection, for 10 days. In patients whose prognosis is short, it may be appropriate to use indwelling catheters throughout the period of care. One published case history, in the end-of-life setting, describes the use of an indwelling catheter in one patient for six days and another patient for 38 days (replacement required at Day 24 because of displacement).10 Outside the context of end-of-life care, it is important to consider more definitive treatments for pain relief before embarking on ISB. In this case, the pain improved during the lifetime of the infusion, allowing its discontinuation and a return to tolerable levels of opioids. This may have reflected the time course of the fracture of the scapula and subsequent stabilization over time. Had this not occurred, we may have been required to continue with the ISB until radiotherapy had an analgesic effect. If radiotherapy was not possible, then the previously discussed options would have been reconsidered. In patients with specific pain syndromes and defined goals of care, indwelling catheters and continuous peripheral nerve blocks can be used to provide rapid, high-quality analgesia. This may be used as a short-term bridging technique to allow provision of definitive treatments, but it also may have a longer-term role within the end-of-life setting. Considering the use of this technique and other developing techniques could provide patients with highly individualized solutions to complex pain problems.
References 1. Fischer H. Focus on: acute palliative care. Curr Anaesth Crit Care 2001;12:309e314.
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2. Ganapathy S, Amendola A, Lichfield R, Fowler P, Ling E. Elastomeric pumps for ambulatory patient controlled regional analgesia. Can J Anaesth 2000;47(9):897e902. 3. Lenters T, Davies J, Matsen F. The types and severity of complications associated with interscalene brachial plexus block anesthesia: local and national evidence. J Shoulder Elbow Surg 2007;16: 379e387. 4. Bollini C. Interscalene brachial plexus blockade. Tech Reg Anesth Pain Manag 2006;10:89e94. 5. Perlas A, Chan V. Ultrasound-guided interscalene brachial plexus block. Tech Reg Anesth Pain Manag 2004;8:143e148. 6. Barnes S, Russell S. Interscalene blocks: care in the ambulatory setting. J Perianesth Nurs 2004; 19(5):352e354. 7. Chidiac E, Wetzel A, Dhade S, Petersen S. Patient survey of continuous interscalene analgesia at home after shoulder surgery. Reg Anesth Pain Med 2006;31(5, S1):63. 8. Ilfeld B, Morey T, Wright T, Chidgey L, Enneking F. Continuous interscalene brachial plexus block for postoperative pain control at home: a randomized, double-blinded, placebo-controlled Study. Anesth Analg 2003;96:1089e1095. 9. Bryan N, Swenson J, Greis P, Burks R. Indwelling interscalene catheter use in an outpatient setting for shoulder surgery: technique, efficacy, and complications. J Shoulder Elbow Surg 2007;16:388e395. 10. Clark A, Simpson K, Ellis F. Continuous brachial plexus block in the management of intractable cancer pain in the arm. Palliat Med 1990;4(2):123e125. 11. Hicks F, Simpson K. Nerve blocks in palliative care. Oxford, UK: Oxford University Press, 2004. 12. Lipton S. Pain relief in active patients with cancer: the early use of nerve blocks improves the quality of life. Br Med J 1989;298:37e38. 13. Percutaneous cementoplasty for palliative treatment of bony malignanciesdguidance IPG179. London: National Institute for Clinical Excellence, 2006. 14. Stepanek E, Joseph S, Campbell P, Porte M. Embolization of a limb metastasis in renal cell carcinoma as a palliative treatment of bone pain. Clin Radiol 1999;54(12):855e857. 15. Patti J, Neeman Z, Wood B. Radiofrequency ablation for cancer-associated pain. J Pain 2002; 3(6):471e473. 16. Radeleff B, Eiers M, Lopez-Benitez R, et al. Transarterial embolization of primary and secondary tumors of the skeletal system. Eur J Radiol 2006;58(1):68e75. 17. Loyd R, Ball P, Fanciullo G. Surgical procedures for intractable cancer pain. Tech Reg Anesth Pain Manag 2005;9(3):167e176.
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18. Skryabina E, Dunn S. Disposable infusion pumps. Am J Health Syst Pharm 2006;63(13):1260e1268. 19. Ludot H, Berger J, Pichenot V, et al. Continuous peripheral nerve block for postoperative pain control at home: a prospective feasibility study in children. Reg Anesth Pain Med 2008;33(1):52e56.
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20. Capdevila X, Pirat P, Bringuier S, et al. Continuous peripheral nerve blocks in hospital wards after orthopedic surgery: a multicenter prospective analysis of the quality of postoperative analgesia and complications in 1,416 patients. Anesthesiology 2005;103(5):1035e1045.
Journal of Pain and Symptom Management
629
Palliative Care Rounds
Outpatient Continuous Interscalene Brachial Plexus Block in Cancer-Related Pain Deans Buchanan, BSc, MBChB, MRCP, Emma Brown, BSc, MBChB, MRCP, FRCR, Fergus Millar, MBChB, FFARCSI, Fiona Mosgrove, BMSc, MBChB, Raj Bhat, MBBS, MS, FRCS(Ed), FRCS(Glas), FRCR, and Pamela Levack, MBChB, FRCP Departments of Palliative Medicine and Supportive Care (D.B., P.L.), Clinical Oncology (E.B., F.M.), Anaesthesia (F.M.), and Radiology (R.B.), Ninewells Hospital, Dundee, Scotland, United Kingdom
Abstract This case outlines the use of a continuous interscalene brachial plexus block to treat cancerrelated pain. Using an elastomeric device, the patient’s previously intractable pain was controlled and he was able to return home. Furthermore, the patient developed a pragmatic and effective method of balancing loss of power and sensation against pain control using the flow restrictor. This case illustrates the potential of an integrated approach to cancer pain management to obtain rapid pain relief in the acute hospital setting. J Pain Symptom Manage 2009;38:629e634. Ó 2009 U.S. Cancer Pain Relief Committee. Published by Elsevier Inc. All rights reserved. Key Words Interscalene block, cancer pain, elastomeric device, continuous peripheral nerve block
Introduction Regional anesthetic techniques are widely used for pain management in both malignant and nonmalignant conditions.1 Recent developments in portable infusion delivery devices have allowed the expansion of the role of nerve blockade.2 Interscalene brachial plexus block (ISB) is widely used to provide analgesia and anesthesia to the shoulder and proximal upper limb.3 It is usually considered within the postoperative setting and is associated with reduced pain, reduced opioid requirements, and reduced side effects.4 Complications can occur during insertion (although these are reduced
Address correspondence to: Deans Buchanan, BSc, MBChB, Roxburghe House, Royal Victoria Hospital, Jedburgh Road, Dundee DD1 1SP, Scotland, United Kingdom. E-mail: [email protected] Accepted for publication: December 10, 2008. Ó 2009 U.S. Cancer Pain Relief Committee Published by Elsevier Inc. All rights reserved.
by using ultrasound guidance5) and also as a result of the indwelling catheter. These complications can include brachial plexopathy, pneumothorax, local anesthetic reactions, arrhythmias, hemidiaphragmatic paralysis, and line-related infection.4 There is now increasing use of this technique in postoperative outpatients using elastomeric devices to provide continuous infusions of local anesthetic.6 Outpatient use has been shown to be acceptable to patients;7 provide potent analgesia with significantly less pain, opioid consumption, and opioid side effects as compared with placebo;8 and have a low complication rate.9 Peripheral nerve blockade in cancer-related pain must be considered within the context of goals of care, likely prognosis, and planned definitive treatments.1 ISB has been used in intractable cancer-related pain10 using a syringe driver, but the use of elastomeric devices has not been reported in this context. 0885-3924/09/$esee front matter doi:10.1016/j.jpainsymman.2008.11.012
630
Buchanan et al.
This case describes the use of an indwelling catheter and elastomeric device to provide continuous analgesia in a patient with renal cancer and a painful glenoid metastasis with associated fracture. The ISB was initially used as inpatient analgesia and subsequently provided outpatient analgesia.
Case History A 66-year-old gentleman diagnosed with a clear cell carcinoma of the left kidney underwent a left nephrectomy. After developing left shoulder pain, plain radiographs revealed a lytic lesion within the glenoid and an associated pathological fracture. Palliative radiotherapy was arranged and delivered to this area. Before commencing interferon chemotherapy, his pain increased and admission was required. It was agreed that interferon would be delayed until the situation could be improved. The patient was referred to the hospital palliative care team for pain control. Pain was maximal in the anterior shoulder, with no characteristics or clinical signs of neuropathic pain. Rest pain was scored as 5e7/10 on a numeric rating scale (NRS), and movement-related incident pain was rated as 8e10/10, lasting for four to five minutes after movement ceased. Range of movement of the shoulder was severely restricted and activities of daily living, such as dressing and eating, were disturbed. A collar and cuff sling had been tried to no benefit. The patient wished to retain full function and to be free of the pain with a low medication burden. He was particularly concerned about sedation as a side effect. Baseline analgesia consisted of a combination of paracetamol (acetaminophen) 1 g and codeine 60 mg three times daily, diclofenac 50 mg twice daily, and oxycodone immediate release 10 mg as required. Morphine had not been tolerated because of sedation and nausea. The submaximal frequency of dosing was related to the patient’s own concerns over toxicity and renal function. Codeine was discontinued, the paracetamol was increased to four times daily, and diclofenac was increased to three times daily. Oral
Vol. 38 No. 4 October 2009
hydromorphone slow-release was commenced at 2 mg twice daily, with 1.3 mg immediaterelease capsules as needed. The background hydromorphone was titrated against rest pain to 8 mg twice daily, reducing NRS to 3e4/10. Incident pain remained severe, and mild opioid toxicities of sedation and myoclonus were present. First-line breakthrough analgesia was changed to the shorter-acting opioid fentanyl (400 mcg) using transmuscosal delivery. Sedation remained a problem. Orthopedic and interventional radiology opinions were sought to consider definitive treatments (surgery, percutaneous cementoplasty, percutaneous radiofrequency ablation, or percutaneous embolization). A computed tomography (CT) scan of the affected shoulder was performed to allow detailed assessment. The anesthesia team was contacted to consider ISB plexus blockade to provide interim analgesia and facilitate opioid reduction. A 20G polyamide catheter was inserted using an 18G 50mm Tuohy needle (Pajunk, Geisingen, Germany) under ultrasound guidance. This was then attached to a 500 mL EasypumpÒ disposable ambulatory elastomeric infusion device (Braun, Melsungen, Germany). Elastomeric infusion devices consist of a distendable bulb housed within a protective shell attached to delivery tubing and a bacterial filter.1 Initial insertion and test dosing showed good placement and effect. Ropivacaine 0.2% was delivered at a restricted flow rate of 5 mL/hour. Pain at rest was mostly abolished, with the exception of an occasional ‘‘ache’’ (1e2/10) and incident pain was reduced to 3e4/10, with a dramatic increase in the range of movement. Activities of daily living were resumed. The initial catheter was placed without subcutaneous tunneling and became displaced after 24 hours. The pain profile returned to baseline and a further procedure was carried out. The second catheter was tunneled subcutaneously and the patient’s own ‘‘waist bag’’ (a small travel bag secured around the waist with a pouch at the front) was used to house the heavier weight of the reservoir. The hydromorphone was reduced to 4 mg twice daily with no loss of pain control. Over the next 24 hours, the patient developed a technique for balancing the numbing side effects of the ropivacaine and the analgesia. Using the clamp, he was able to restrict the
Vol. 38 No. 4 October 2009
Interscalene Block for Cancer-Related Pain
flow when the numbness increased and release the flow when he felt early sensation of pain. This had the effect of prolonging the lifetime of each reservoir and placed some control back into the patient’s hands. CT imaging of the shoulder revealed a large lytic lesion in the scapula. This measured approximately 6 cm in maximum diameter and eroded the articular surface of the glenoid. There was a pathological fracture through the body of the scapula. Surgical options were limited to amputation. Radiological interventions were limited to embolization, with some risks. With the distribution of the lytic lesion outlined by CT, it was decided that further outpatient radiotherapy could be delivered using CT planning. The potential complications of the indwelling catheter and blockade were explained and the patient was allowed to return home. Breakthrough analgesia was provided as originally outlined and, in the event of complications, a plan of return was agreed. A date to return to change the reservoir was also arranged. On return, the patient described good pain control throughout the three days at home and reported that, by Day 2, he had been able to stop the flow of anesthetic completely. The catheter was reviewed: there were no signs of infection and it remained in the correct position. He was able to go home, this time with an elastomeric device primed and available for direct attachment if the pain returned. His hydromorphone was provided in 2 mg tablets to allow dose reduction if the pain remained controlled. A further review date was set to correspond to CT scan planning for further radiotherapy. At Day 10, he was reviewed and the pain remained under control, without the infusion being required. There were no visible signs of infection at the catheter site. The catheter was removed. Radiotherapy was delivered, with no complications, and pain remained controlled on 2 mg hydromorphone twice daily. After four weeks, despite some residual shoulder stiffness, the patient was able to discontinue all analgesics with no ongoing pain. Interferon therapy was eventually commenced and the patient remained under treatment four months after the interscalene block.
631
Discussion Most of the cancer-related pains can be managed successfully using oral analgesia and noninvasive methods. However, for some patients, more complex interventions may be required to achieve control within an acceptable time frame and within a tolerable therapeutic window.11 Early intervention in selected patients can lead to improved quality of life.12 This needs to be placed firmly within the context of patients’ goals and clear understanding of both the limitations and possible complications of invasive techniques. This case highlights the importance of using invasive techniques to achieve pain relief in patients who have intractable pain or intolerable side effects from systemic analgesia. It also illustrates the potential of an integrated approach in cancer pain management to obtain rapid pain relief in the acute hospital setting. A wide range of peripheral nerves can be blocked to target different pains: interscalene block (shoulder and upper limb), intercostal block (chest wall) and lumbar or sacral plexus blocks (pelvis and lower limbs).1 Fischer outlines the two main utilities of peripheral nerve blockade in palliative medicine as short-term use (aiding diagnosis of the cause of the pain and acting as bridging analgesia to allow introduction of other therapies) and longer-term use in the treatment of pain resulting from peripheral nerve damage.1 Other therapies may include physiotherapy (within an analgesic window), surgery, radiological interventions, and oncological treatments. Newer techniques for pain control are becoming available but may require a period of radiological assessment and planning before they can be provided. Such techniques include cementoplasty,13 embolization,14 and radiofrequency ablation15 of painful bone metastases. In this case, these procedures were considered, but the breach in the articular surface of the shoulder joint was a contraindication to cementoplasty because of the risk of an intra-articular cement leak. Radiofrequency ablation was also inappropriate because of the lesion’s size and its proximity to the brachial plexus. Embolization was technically possible. The risks of embolization included increased pain post procedure (although
632
Buchanan et al.
nerve blockade would reduce this) but a risk of loss of joint architecture and reduction or loss of shoulder function. The pain relief in the medium term after embolization is also difficult to predict and there is only limited evidence available for its use in the palliative setting.16 The patient did not wish to pursue this procedure. With the enhanced information regarding location of the fracture and metastases, it was possible to provide further targeted external beam radiotherapy. If this had not been the case, then embolization may have been reconsidered. However, as the pain was unilateral, a further option for pain control was percutaneous anterolateral cordotomy.17 The patient was highly motivated and wished to obtain maximal analgesia and limb function with minimal side effects alongside a low tablet burden. In addition, it was important that he remained mobile and was able to be managed as an outpatient. Elastomeric devices are one type of disposable infusion pumps that have been developed over the last 25 years. Disposable pumps have been used in a variety of settings to provide hospital and community-based therapies, including chemotherapy, antimicrobials, opioid analgesia, and continuous regional anesthesia.18 Continuous peripheral nerve blockade, including ISB blocks, are used predominately in the surgical setting.4 They were initially used in the inpatient population, but the ability to deliver infusions using elastomeric devices has allowed this to be extended to outpatient use. In the adult postoperative setting, short-term outpatient infusions have been shown to be safe, effective, and acceptable to patients.2,8 Furthermore, Ludot et al. described the use of outpatient elastomeric devices for continuous peripheral nerve blockade in 47 children undergoing ankle or foot surgery.19 In this study, the parents provided ongoing surveillance for complications, with good analgesia, satisfaction, and quality of life observed in most of the cases.19 The elastomeric reservoir used in this case could accommodate a volume of 500 mL and the flow rate was set at 5 mL/hour. As such, approximately 100 hours (four days) of drug delivery was available. The patient’s own ingenuity produced a situation in which the flow rate of ropivicaine was managed using the on/ off valve to balance loss-of-arm sensation and
Vol. 38 No. 4 October 2009
level of analgesia. This also had the effect of extending the time over which the drug would be delivered. It is of note that patient-controlled continuous interscalene regional anesthesia has been previously documented, with patient education regarding ‘‘top-up’’ boluses and clamping being provided to allow flexible use; in the group receiving perineural infusion of the ropivicaine compared with placebo, this randomized, double-blind, placebo-controlled trial found less pain, reduced opioid use, had fewer side effects, reduced sleep disturbance, and had low levels of complications.8 Interscalene blocks were described as early as 1919, but the approach was refined over subsequent years. A detailed description of the block is provided by Bollini.4 ISB targets the most superior and proximal components of the brachial plexus, producing regional anesthesia in the shoulder and upper limb. The procedure previously relied on techniques to assess needle proximity to the target nerve (nerve stimulation or test dosing). The introduction of ultrasound guidance allows direct visualization. The use of ultrasound appears to decrease the time required for placement of the block, reduce immediate complications, and improve block quality.5 It also may increase the acceptability of the procedure itself by avoiding the discomfort associated with nerve stimulation.9 Most of the published data describes the use of indwelling continuous nerve blocks over a short postoperative period of two to five days. Within this time frame, there are low levels of clinically observable infection. In one large multicenter study of 1416 patients with peripheral postsurgical nerve blocks (256 were ISB), only 3% had clinical signs of infection, but 28.7% had positive catheter-tip cultures after removal. Most of the cultures were positive for coagulase-negative staphylococcus (61%); some of these likely represent skin contaminants on removal.20 Other potential complications specific to ISB include neurovascular injury on insertion, inadvertent intravascular local anesthetic injection, pneumothorax, phrenic nerve palsy, transient hemidiaphragmatic paralysis (because of blockade of C3, 4, and 5 roots), Horner’s syndrome, and recurrent laryngeal palsy.3 It has been noted that these more serious complications are both rare and seldom permanent.9 Bryan et al. reviewed 147 consecutive ISB used in the outpatient setting and found no
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Interscalene Block for Cancer-Related Pain
episodes of neurovascular injury, infection, or anesthetic toxicity. The only insertion-related complication was a small self-resolving pneumothorax. Fourteen patients experienced minor adverse events, eight had inadequate analgesia, and four had catheters dislodged. No episodes of infection were reported.9 It is not clear for what duration catheters can safely remain in situ. In our own patient, the first catheter was in situ for only 24 hours until it became dislodged. The second catheter remained in situ, with no evidence of infection, for 10 days. In patients whose prognosis is short, it may be appropriate to use indwelling catheters throughout the period of care. One published case history, in the end-of-life setting, describes the use of an indwelling catheter in one patient for six days and another patient for 38 days (replacement required at Day 24 because of displacement).10 Outside the context of end-of-life care, it is important to consider more definitive treatments for pain relief before embarking on ISB. In this case, the pain improved during the lifetime of the infusion, allowing its discontinuation and a return to tolerable levels of opioids. This may have reflected the time course of the fracture of the scapula and subsequent stabilization over time. Had this not occurred, we may have been required to continue with the ISB until radiotherapy had an analgesic effect. If radiotherapy was not possible, then the previously discussed options would have been reconsidered. In patients with specific pain syndromes and defined goals of care, indwelling catheters and continuous peripheral nerve blocks can be used to provide rapid, high-quality analgesia. This may be used as a short-term bridging technique to allow provision of definitive treatments, but it also may have a longer-term role within the end-of-life setting. Considering the use of this technique and other developing techniques could provide patients with highly individualized solutions to complex pain problems.
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2. Ganapathy S, Amendola A, Lichfield R, Fowler P, Ling E. Elastomeric pumps for ambulatory patient controlled regional analgesia. Can J Anaesth 2000;47(9):897e902. 3. Lenters T, Davies J, Matsen F. The types and severity of complications associated with interscalene brachial plexus block anesthesia: local and national evidence. J Shoulder Elbow Surg 2007;16: 379e387. 4. Bollini C. Interscalene brachial plexus blockade. Tech Reg Anesth Pain Manag 2006;10:89e94. 5. Perlas A, Chan V. Ultrasound-guided interscalene brachial plexus block. Tech Reg Anesth Pain Manag 2004;8:143e148. 6. Barnes S, Russell S. Interscalene blocks: care in the ambulatory setting. J Perianesth Nurs 2004; 19(5):352e354. 7. Chidiac E, Wetzel A, Dhade S, Petersen S. Patient survey of continuous interscalene analgesia at home after shoulder surgery. Reg Anesth Pain Med 2006;31(5, S1):63. 8. Ilfeld B, Morey T, Wright T, Chidgey L, Enneking F. Continuous interscalene brachial plexus block for postoperative pain control at home: a randomized, double-blinded, placebo-controlled Study. Anesth Analg 2003;96:1089e1095. 9. Bryan N, Swenson J, Greis P, Burks R. Indwelling interscalene catheter use in an outpatient setting for shoulder surgery: technique, efficacy, and complications. J Shoulder Elbow Surg 2007;16:388e395. 10. Clark A, Simpson K, Ellis F. Continuous brachial plexus block in the management of intractable cancer pain in the arm. Palliat Med 1990;4(2):123e125. 11. Hicks F, Simpson K. Nerve blocks in palliative care. Oxford, UK: Oxford University Press, 2004. 12. Lipton S. Pain relief in active patients with cancer: the early use of nerve blocks improves the quality of life. Br Med J 1989;298:37e38. 13. Percutaneous cementoplasty for palliative treatment of bony malignanciesdguidance IPG179. London: National Institute for Clinical Excellence, 2006. 14. Stepanek E, Joseph S, Campbell P, Porte M. Embolization of a limb metastasis in renal cell carcinoma as a palliative treatment of bone pain. Clin Radiol 1999;54(12):855e857. 15. Patti J, Neeman Z, Wood B. Radiofrequency ablation for cancer-associated pain. J Pain 2002; 3(6):471e473. 16. Radeleff B, Eiers M, Lopez-Benitez R, et al. Transarterial embolization of primary and secondary tumors of the skeletal system. Eur J Radiol 2006;58(1):68e75. 17. Loyd R, Ball P, Fanciullo G. Surgical procedures for intractable cancer pain. Tech Reg Anesth Pain Manag 2005;9(3):167e176.
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20. Capdevila X, Pirat P, Bringuier S, et al. Continuous peripheral nerve blocks in hospital wards after orthopedic surgery: a multicenter prospective analysis of the quality of postoperative analgesia and complications in 1,416 patients. Anesthesiology 2005;103(5):1035e1045.