Attempting to Prevent Persistent Postamputation Phantom Limb and Stump Pain Jonathan Cheah, MD, Edward Yap, MD, and Ramana Naidu, MD Persistent postsurgical pain after amputation is common and has a number of proposed risk factors. We describe the management of a patient with persistent pain after a below-the-knee amputation. We used a combination of general, peripheral, and neuraxial anesthesia techniques to control postoperative phantom limb and stump pain in a patient at high risk for developing chronic pain. With preemptive management and mechanism-directed therapies, adequate preoperative and postoperative pain control were achieved in attempts to reduce the risk of chronic phantom limb pain. (A&A Case Reports. 2014;3:35–7.)
C
ontinued pain after major limb amputation is common, and the incidence and severity of postamputation pain is higher in those with severe uncontrolled pain preamputation.1–4 In the United States, the prevalence of limb loss was 1.6 million in 1996.5 This poses a significant concern because the incidence of chronic pain after amputation is estimated to be 30% to 85%.2,6,7 Of these postamputation patients with chronic pain, it is estimated that 5% to 10% will develop severe, disabling pain.2,6 Preventive pain management to reduce preoperative and postoperative acute pain has been suggested to reduce the development of chronic phantom limb pain and stump pain.8–11 Epidural, regional, and intrathecal anesthesia and analgesia techniques have been used to achieve adequate pain control and potentially reduce long-term analgesic needs.9,12–15 We describe a case that used several techniques to improve acute postoperative pain control with the long-term goal of preventing persistent phantom limb pain. Written informed consent was obtained from the patient for permission to publish this case report.
CASE DESCRIPTION
A 47-year-old (weight 90 kg, height 1.83 m, body mass index 26.9 kg/m2) man with right distal lower leg liposarcoma presented for orthopedic oncology consultation and potential definitive treatment by below-the-knee amputation. His medical history was significant for hypertension, insulin-dependent type 1 diabetes mellitus, and lower leg pain managed with hydrocodone–acetaminophen. Four weeks earlier, he had undergone surgical excisional biopsy of a 4.6 × 3.6 × 2.1-cm mass on his right posterior ankle at an outside hospital. The biopsy was subsequently diagnosed as a grade 2 myxoid/round cell liposarcoma with positive surgical margins involving the Achilles tendon. Since the initial biopsy, the patient had remained non–weight bearing From the Department of Anesthesia and Perioperative Care, University of California, San Francisco, San Francisco, California. Accepted for publication January 9, 2014. Funding: None. The authors declare no conflicts of interest. Address correspondence to Jonathan Cheah, MD, Department of Anesthesia and Perioperative Care, UCSF Pain Management Center, University of California, San Francisco, 521 Parnassus Ave., Room C-450, San Francisco, CA 94143. Address e-mail to [email protected]. Copyright © 2014 International Anesthesia Research Society DOI: 10.1213/XAA.0000000000000038
August 1, 2014 • Volume 3 • Number 3
and controlling his pain with oral ibuprofen approximately 800 mg daily and 5 to 6 tablets of hydrocodone–acetaminophen (5/325 mg) per day. Before the biopsy, the patient had minor discomfort from the mass and had used ibuprofen 200 mg 1 to 2 oral tablets daily. His postbiopsy pain was described as tolerable with a pain score of 2 to 4 on the Numeric Rating Scale (NRS). After a discussion of the risks and benefits of surgical intervention, the surgical team and the patient planned for a below-the-knee amputation for local tumor control, optimal functional outcome with a prosthesis, and the potential to avoid chemotherapy and radiation therapy in the setting of poor healing related to diabetes. Preoperative evaluation identified a history of hypertension controlled at a baseline of 120/80 mm Hg with one 100 mg tablet of losartan daily. This was discontinued the day before surgery. Blood glucose was controlled with subcutaneous lispro insulin 100 U before meals and subcutaneous detemir insulin approximately 52 U a day. Hemoglobin A1C was 7% with a preoperative blood glucose of 174 mg/ dL. Preoperative complete blood count, basic metabolic panel, and coagulation panel were within the normal limits. He denied a history of psychiatric or mood/anxiety disorders and expressed that he was motivated for definitive treatment. Previously, he had an active lifestyle and was a very industrious used-car salesman. His social history included cessation of smoking 4 weeks earlier, drinking 3 glasses of wine per week, and denial of illicit drug use. His postbiopsy examination of the extremity demonstrated a slow-healing wound, but had no signs of infection. Otherwise, the patient had an unremarkable review of systems and physical examination. He was assessed as an ASA physical status II and consented for general anesthesia plus epidural analgesia for postoperative pain management. After IV midazolam as premedication, an epidural catheter was inserted uneventfully via the L4-5 interspace and an epidural infusion of 0.5% ropivacaine at 6 mL/h was started before surgery to establish a block for preoperative analgesia. General anesthesia was then induced with propofol 2 mg/kg and fentanyl 200 mcg and maintained with desflurane via a laryngeal mask airway. During the surgical procedure, the tibial nerve was isolated after the neural vascular bundle was identified for control of hemostasis. The tibial nerve sheath was then injected with approximately 1 to 2 mL of 0.5% bupivacaine before transection. Identification of other smaller nerves was not included in the surgical technique. The surgical procedure was completed without cases-anesthesia-analgesia.org
35
complication with an estimated blood loss of 100 mL. In the postanesthesia care unit, the patient rated his pain as an NRS 0 to 1 with analgesia transitioned to a 0.125% ropivacaine epidural infusion with 2 mcg/mL fentanyl at 12 mL/h. Postoperative radiographs confirmed proper amputation of the extremity with appropriate soft tissue coverage. After recovery from anesthesia and transfer to the hospital ward (approximately 6 to 8 hours postoperatively), the patient experienced the onset of excruciating pain described as intermittent episodes of sharp, stabbing pain with an intensity graded as NRS 10. He complained of pain below the level of the amputation that was consistent with phantom limb sensation/pain. In addition, he was experiencing stump pain that extended proximally to the upper shin and thigh. Repeated use of additional IV fentanyl and hydromorphone did not decrease his NRS scores. The epidural level was assessed as adequate with lack of cold sensation bilaterally below the umbilicus. A bolus of 8 mL of 0.25% ropivacaine was then used to reduce NRS scores from 10 to 5. Subsequently, the ropivacaine infusion concentration was increased to 0.25% with fentanyl 2 mcg/mL at a lower rate of 8 mL/h based on the response to the bolus volume and concern for hypotension. With the epidural infusion increase and addition of an IV hydromorphone patient-controlled analgesia, the patient felt that moderate pain control was achieved for the evening of postoperative day zero (POD 0). Adjuvant therapy throughout the hospitalization included scheduled oral acetaminophen 1000 mg every 6 hours and oral lorazepam approximately 4 to 6 mg daily. Gabapentin 600 mg 3 times a day was begun on POD 1 with the goal of increasing the dose to 900 mg 3 times a day (POD 2) and ultimately 1200 mg 3 times a day (POD 3) as tolerated. In the late morning of POD 1, the patient continued to have uncontrolled stump and phantom pain symptoms (NRS 4–10) that were unrelieved with repeated epidural ropivacaine boluses and escalating doses of IV hydromorphone. After a discussion regarding the risk and benefits of alternative therapies, the patient and acute pain service agreed that the epidural infusion was inadequate and that regional anesthesia may improve pain coverage. The epidural catheter was removed, and femoral (L2-4) and sciatic (L4-S3) peripheral nerve catheters were placed using ultrasound guidance. Before catheter placement, we injected 0.25% ropivacaine 20 mL at the sciatic nerve site and 0.25% ropivacaine 15 mL at the femoral nerve site. The peripheral catheter infusions were then started with 0.2% ropivacaine at 8 mL/h. An IV ketamine infusion at 2 mcg/kg/min was also started as adjuvant therapy, but was discontinued due to patient-reported side effects of altered sensorium and confusion. The gabapentin dose was maintained at 600 mg 3 times a day since the patient tolerated this dosage and did not want possible sedation from an increase in gabapentin to worsen his confusion. Moderate improvements of analgesia were achieved, and the patient felt that he was at a tolerable level of pain throughout the evening (NRS 5). During the morning of POD 2, the patient’s pain worsened with an overall increase in severity and he considered it to be uncontrolled (NRS 7–10). While catheter positions appeared unchanged on the skin surface, repeat peripheral catheter boluses did not improve analgesia, and it was thought that his increased pain was likely due to migration
36 cases-anesthesia-analgesia.org
of the catheters within the deeper soft tissues. At this point, the patient expressed feelings of hopelessness and had thoughts that there would be neither a resolution nor an improvement in the severe agony that he was experiencing. He was reluctant to repeat the previous interventions and was motivated to attempt alternative therapies within reason. Thus, it was decided together with the patient to remove the peripheral catheters and transition to a L4-5 intrathecal catheter infusion with the goal of providing a dense blockade of lumbar and sacral nerve roots. The catheter was placed with the patient in the prone position since he felt that such a position was the most tolerable. Markedly improved analgesia was achieved with an infusion of bupivacaine 0.15% at 1.5 mg/h. This enabled the patient to feel significantly more comfortable and begin advancement with passive physical therapy. While his acute stump and phantom pain were completely abated, he continued to experience nonpainful phantom limb sensations. Surgical and nursing staff members were educated about the specifics of managing an intrathecal infusion, and the catheter was marked extensively to prevent misidentification and misuse. The acute pain service served as the primary consultant for management of the intrathecal infusion and catheter care. As his physical therapy advanced to sitting in a chair, he was transitioned from the hydromorphone patientcontrolled analgesia to oral analgesic medications on POD 3. On POD 4, the intrathecal catheter infusion was stopped and he was able to further advance his activity to mobility exercises with a walker. After discontinuing the intrathecal infusion, he was discharged on the evening of POD 4 with mild to moderate tolerable pain (NRS 2–5) receiving an oral regimen of oxycodone, acetaminophen, and gabapentin. Two months postoperatively, the patient described minimal to moderate intermittent and nonpainful foot sensation consistent with phantom limb sensations. He also described occasional NRS 4 phantom limb pain that he felt to be manageable with oral medications of hydrocodone– acetaminophen (approximately 2–4 tablets/d), gabapentin 600 mg 3 times a day, and cyclobenzaprine 10 mg 3 times a day. Additionally, he is pursuing mirror box therapy as an adjuvant treatment to further reduce the frequency and intensity of the occasional painful phantom limb episodes.
DISCUSSION
Major limb amputation is an invasive surgical procedure associated with a frequent incidence of postoperative pain and a high likelihood of developing chronic stump and/or phantom pain.6,7,11 Kehlet et al.2 have postulated several risk factors associated with the development of chronic pain: preoperative pain, acute postoperative pain, invasiveness of surgery, genetic susceptibility, young age, sex, and psychosocial factors (such as catastrophization). Our patient was at high risk for the development of chronic pain due to preoperative pain at the slow-healing biopsy site (likely related to diabetes), severe acute postoperative pain, invasive surgery, and the patient’s feelings of hopelessness after multiple unsuccessful therapies. Thus, the patient, anesthesia team, surgical team, and acute pain service established that comprehensive pre- and postoperative pain coverage was an imperative goal to limit the risk of developing chronic phantom limb and stump pain.
A & A case reports
The pathophysiology of phantom limb pain has been broadly categorized as involving supraspinal, spinal, and peripheral mechanisms that suggest corresponding mechanism-directed therapies.16 With previous studies suggesting that epidural anesthesia can achieve adequate pain control and reduce the risk for chronic pain,9,11 an epidural anesthetic and analgesia plan was devised to minimize preoperative and postoperative pain. This was initiated in the preoperative period before the start of surgery. We acknowledged that a longer period of treatment (48 hours preoperatively) as seen in study by Karanikolas et al.9 may have provided further benefit; however, this was limited by the urgent scheduling for surgical intervention. After an uneventful intraoperative course, many would consider epidural infusion (spinal-directed therapy), intraoperative neural sheath injection (peripheral-directed therapy), and IV opioid therapy (supraspinal-directed therapy) to be adequate techniques to obtain a moderate degree of analgesia. When these primary modalities fail as was the case with this patient, management can be very difficult for both the patient and the care providers. Uncontrolled stump and phantom limb pain was unrelieved by increased epidural anesthesia dosing, escalating liberalization of opioid therapy, and non-opioid adjuvant therapy and led to both a reevaluation of the failed therapies and progression to alternative modalities in the context of evolving postoperative pain. Regional anesthesia (peripheral-directed therapy) was chosen as the next mainstay of analgesia because of realtime ultrasound guidance, a low risk of procedure-related complications, and minimal need to change the patient’s position. Replacing the epidural catheter was considered, but decided against due to the patient’s inability to remain still in the lateral decubitus or sitting position and his lack of confidence in epidural anesthesia from the previous night. The failure of the regional nerve blocks resulted in a deliberation between repeating the failed blocks and proceeding to a more aggressive therapy, in this case an intrathecal catheter infusion. While the use of an intrathecal infusion has been described, it is uncommon as a treatment modality due to its associated risks of postspinal puncture headaches, backache, significant cardiovascular changes, and neurologic injury.17 The decision to proceed required an extensive discussion among the patient, surgical team, acute pain team, and nursing staff to align the goals of care and minimize potential risks. In this case, the intrathecal infusion provided a substantial level of analgesia and also substantially changed the patient’s clinical scenario by establishing lasting relief, improving his mood, increasing his interactions with hospital care providers, and ultimately breaking the potential cycle of catastrophization. Due to the surgical and acute pain services’ concern that the patient’s clinical course and risk factors would result in the development of chronic phantom and stump pain, the patient was recommended to continue care with chronic pain management physicians and mirror box therapy (as an adjuvant supraspinal-directed therapy) to further limit long-term and episodic phantom limb pain. Although the etiology of phantom limb syndrome remains unknown, Ramachandran and Hirstein’s theory of the dissociation18 between the somatosensory cortex and the peripheral somatosensory system remains a leading theory as to why mirror box therapy has been effective.
August 1, 2014 • Volume 3 • Number 3
This case represents an example of how the goals of minimizing pre- and postoperative pain in a high-risk patient can be exceedingly difficult to accomplish. When traditional modalities are unsuccessful, we recommend rapid and vigorous reevaluation and discussion among the patient and care providers regarding the goals of care and the related risks and benefits of alternative therapies. In our patient, an intrathecal infusion provided superior and lasting analgesia against the uncontrolled escalation of phantom limb and stump pain in both the acute postoperative phase and longterm recovery period. E REFERENCES 1. Jensen TS, Krebs B, Nielsen J, Rasmussen P. Immediate and long-term phantom limb pain in amputees: incidence, clinical characteristics and relationship to pre-amputation limb pain. Pain 1985;21:267–78 2. Kehlet H, Jensen TS, Woolf CJ. Persistent postsurgical pain: risk factors and prevention. Lancet 2006;367:1618–25 3. Nikolajsen L, Ilkjaer S, Krøner K, Christensen JH, Jensen TS. The influence of preamputation pain on postamputation stump and phantom pain. Pain 1997;72:393–405 4. Weiss SA, Lindell B. Phantom limb pain and etiology of amputation in unilateral lower extremity amputees. J Pain Symptom Manage 1996;11:3–17 5. Owings MF, Kozak LJ. Ambulatory and inpatient procedures in the United States, 1996. Vital Health Stat 13 1998:1–119 6. Nikolajsen L, Jensen TS. Phantom limb pain. Br J Anaesth 2001;87:107–16 7. Ballantyne JC, Cousins MJ, Giamberardino MA, Jamison RN, McGrath PA, Rajagopal MR, Smith MT, Sommer C, Wittink HM. Clinical updates: chronic pain after surgery or injury. Int Assoc Study Pain 2011;19:1–5 8. Bach S, Noreng MF, Tjéllden NU. Phantom limb pain in amputees during the first 12 months following limb amputation, after preoperative lumbar epidural blockade. Pain 1988;33:297–301 9. Karanikolas M, Aretha D, Tsolakis I, Monantera G, Kiekkas P, Papadoulas S, Swarm RA, Filos KS. Optimized perioperative analgesia reduces chronic phantom limb pain intensity, prevalence, and frequency: a prospective, randomized, clinical trial. Anesthesiology 2011;114:1144–54 10. Woolf CJ, Chong MS. Preemptive analgesia–treating postoperative pain by preventing the establishment of central sensitization. Anesth Analg 1993;77:362–79 11. Hanley MA, Jensen MP, Smith DG, Ehde DM, Edwards WT, Robinson LR. Preamputation pain and acute pain predict chronic pain after lower extremity amputation. J Pain 2007;8:102–9 12. Dahm PO, Nitescu PV, Appelgren LK, Curelaru ID. Long term intrathecal infusion of opioid and/or bupivacaine in the prophylaxis and treatment of phantom limb pain. Neuromodulation 1998:111–28 13. Jacobson L, Chabal C, Brody MC, Mariano AJ, Chaney EF. A comparison of the effects of intrathecal fentanyl and lidocaine on established postamputation stump pain. Pain 1990;40:137–41 14. Borghi B, D’Addabbo M, White PF, Gallerani P, Toccaceli L, Raffaeli W, Tognù A, Fabbri N, Mercuri M. The use of prolonged peripheral neural blockade after lower extremity amputation: the effect on symptoms associated with phantom limb syndrome. Anesth Analg 2010;111:1308–15 15. Fisher A, Meller Y. Continuous postoperative regional analgesia by nerve sheath block for amputation surgery–a pilot study. Anesth Analg 1991;72:300–3 16. Hsu E, Cohen S. Post-amputation pain: epidemiology, mechanisms, and treatment. J Pain Res 2013;6:121–36 17. Miller RD, Eriksson LI, Fleisher LA, Wiener-Kronish GP, Young WL. Chapter 51: Spinal, epidural, and caudal anesthesia. In: Miller RD, ed. Miller’s Anesthesia. 7th ed. Philadelphia, PA: Churchill Livingstone Elsevier, 2009:1618–28 18. Ramachandran, VS, Hirstein W. The perception of phantom limbs. Brain 1998;121:1603–30
cases-anesthesia-analgesia.org
37
C
ontinued pain after major limb amputation is common, and the incidence and severity of postamputation pain is higher in those with severe uncontrolled pain preamputation.1–4 In the United States, the prevalence of limb loss was 1.6 million in 1996.5 This poses a significant concern because the incidence of chronic pain after amputation is estimated to be 30% to 85%.2,6,7 Of these postamputation patients with chronic pain, it is estimated that 5% to 10% will develop severe, disabling pain.2,6 Preventive pain management to reduce preoperative and postoperative acute pain has been suggested to reduce the development of chronic phantom limb pain and stump pain.8–11 Epidural, regional, and intrathecal anesthesia and analgesia techniques have been used to achieve adequate pain control and potentially reduce long-term analgesic needs.9,12–15 We describe a case that used several techniques to improve acute postoperative pain control with the long-term goal of preventing persistent phantom limb pain. Written informed consent was obtained from the patient for permission to publish this case report.
CASE DESCRIPTION
A 47-year-old (weight 90 kg, height 1.83 m, body mass index 26.9 kg/m2) man with right distal lower leg liposarcoma presented for orthopedic oncology consultation and potential definitive treatment by below-the-knee amputation. His medical history was significant for hypertension, insulin-dependent type 1 diabetes mellitus, and lower leg pain managed with hydrocodone–acetaminophen. Four weeks earlier, he had undergone surgical excisional biopsy of a 4.6 × 3.6 × 2.1-cm mass on his right posterior ankle at an outside hospital. The biopsy was subsequently diagnosed as a grade 2 myxoid/round cell liposarcoma with positive surgical margins involving the Achilles tendon. Since the initial biopsy, the patient had remained non–weight bearing From the Department of Anesthesia and Perioperative Care, University of California, San Francisco, San Francisco, California. Accepted for publication January 9, 2014. Funding: None. The authors declare no conflicts of interest. Address correspondence to Jonathan Cheah, MD, Department of Anesthesia and Perioperative Care, UCSF Pain Management Center, University of California, San Francisco, 521 Parnassus Ave., Room C-450, San Francisco, CA 94143. Address e-mail to [email protected]. Copyright © 2014 International Anesthesia Research Society DOI: 10.1213/XAA.0000000000000038
August 1, 2014 • Volume 3 • Number 3
and controlling his pain with oral ibuprofen approximately 800 mg daily and 5 to 6 tablets of hydrocodone–acetaminophen (5/325 mg) per day. Before the biopsy, the patient had minor discomfort from the mass and had used ibuprofen 200 mg 1 to 2 oral tablets daily. His postbiopsy pain was described as tolerable with a pain score of 2 to 4 on the Numeric Rating Scale (NRS). After a discussion of the risks and benefits of surgical intervention, the surgical team and the patient planned for a below-the-knee amputation for local tumor control, optimal functional outcome with a prosthesis, and the potential to avoid chemotherapy and radiation therapy in the setting of poor healing related to diabetes. Preoperative evaluation identified a history of hypertension controlled at a baseline of 120/80 mm Hg with one 100 mg tablet of losartan daily. This was discontinued the day before surgery. Blood glucose was controlled with subcutaneous lispro insulin 100 U before meals and subcutaneous detemir insulin approximately 52 U a day. Hemoglobin A1C was 7% with a preoperative blood glucose of 174 mg/ dL. Preoperative complete blood count, basic metabolic panel, and coagulation panel were within the normal limits. He denied a history of psychiatric or mood/anxiety disorders and expressed that he was motivated for definitive treatment. Previously, he had an active lifestyle and was a very industrious used-car salesman. His social history included cessation of smoking 4 weeks earlier, drinking 3 glasses of wine per week, and denial of illicit drug use. His postbiopsy examination of the extremity demonstrated a slow-healing wound, but had no signs of infection. Otherwise, the patient had an unremarkable review of systems and physical examination. He was assessed as an ASA physical status II and consented for general anesthesia plus epidural analgesia for postoperative pain management. After IV midazolam as premedication, an epidural catheter was inserted uneventfully via the L4-5 interspace and an epidural infusion of 0.5% ropivacaine at 6 mL/h was started before surgery to establish a block for preoperative analgesia. General anesthesia was then induced with propofol 2 mg/kg and fentanyl 200 mcg and maintained with desflurane via a laryngeal mask airway. During the surgical procedure, the tibial nerve was isolated after the neural vascular bundle was identified for control of hemostasis. The tibial nerve sheath was then injected with approximately 1 to 2 mL of 0.5% bupivacaine before transection. Identification of other smaller nerves was not included in the surgical technique. The surgical procedure was completed without cases-anesthesia-analgesia.org
35
complication with an estimated blood loss of 100 mL. In the postanesthesia care unit, the patient rated his pain as an NRS 0 to 1 with analgesia transitioned to a 0.125% ropivacaine epidural infusion with 2 mcg/mL fentanyl at 12 mL/h. Postoperative radiographs confirmed proper amputation of the extremity with appropriate soft tissue coverage. After recovery from anesthesia and transfer to the hospital ward (approximately 6 to 8 hours postoperatively), the patient experienced the onset of excruciating pain described as intermittent episodes of sharp, stabbing pain with an intensity graded as NRS 10. He complained of pain below the level of the amputation that was consistent with phantom limb sensation/pain. In addition, he was experiencing stump pain that extended proximally to the upper shin and thigh. Repeated use of additional IV fentanyl and hydromorphone did not decrease his NRS scores. The epidural level was assessed as adequate with lack of cold sensation bilaterally below the umbilicus. A bolus of 8 mL of 0.25% ropivacaine was then used to reduce NRS scores from 10 to 5. Subsequently, the ropivacaine infusion concentration was increased to 0.25% with fentanyl 2 mcg/mL at a lower rate of 8 mL/h based on the response to the bolus volume and concern for hypotension. With the epidural infusion increase and addition of an IV hydromorphone patient-controlled analgesia, the patient felt that moderate pain control was achieved for the evening of postoperative day zero (POD 0). Adjuvant therapy throughout the hospitalization included scheduled oral acetaminophen 1000 mg every 6 hours and oral lorazepam approximately 4 to 6 mg daily. Gabapentin 600 mg 3 times a day was begun on POD 1 with the goal of increasing the dose to 900 mg 3 times a day (POD 2) and ultimately 1200 mg 3 times a day (POD 3) as tolerated. In the late morning of POD 1, the patient continued to have uncontrolled stump and phantom pain symptoms (NRS 4–10) that were unrelieved with repeated epidural ropivacaine boluses and escalating doses of IV hydromorphone. After a discussion regarding the risk and benefits of alternative therapies, the patient and acute pain service agreed that the epidural infusion was inadequate and that regional anesthesia may improve pain coverage. The epidural catheter was removed, and femoral (L2-4) and sciatic (L4-S3) peripheral nerve catheters were placed using ultrasound guidance. Before catheter placement, we injected 0.25% ropivacaine 20 mL at the sciatic nerve site and 0.25% ropivacaine 15 mL at the femoral nerve site. The peripheral catheter infusions were then started with 0.2% ropivacaine at 8 mL/h. An IV ketamine infusion at 2 mcg/kg/min was also started as adjuvant therapy, but was discontinued due to patient-reported side effects of altered sensorium and confusion. The gabapentin dose was maintained at 600 mg 3 times a day since the patient tolerated this dosage and did not want possible sedation from an increase in gabapentin to worsen his confusion. Moderate improvements of analgesia were achieved, and the patient felt that he was at a tolerable level of pain throughout the evening (NRS 5). During the morning of POD 2, the patient’s pain worsened with an overall increase in severity and he considered it to be uncontrolled (NRS 7–10). While catheter positions appeared unchanged on the skin surface, repeat peripheral catheter boluses did not improve analgesia, and it was thought that his increased pain was likely due to migration
36 cases-anesthesia-analgesia.org
of the catheters within the deeper soft tissues. At this point, the patient expressed feelings of hopelessness and had thoughts that there would be neither a resolution nor an improvement in the severe agony that he was experiencing. He was reluctant to repeat the previous interventions and was motivated to attempt alternative therapies within reason. Thus, it was decided together with the patient to remove the peripheral catheters and transition to a L4-5 intrathecal catheter infusion with the goal of providing a dense blockade of lumbar and sacral nerve roots. The catheter was placed with the patient in the prone position since he felt that such a position was the most tolerable. Markedly improved analgesia was achieved with an infusion of bupivacaine 0.15% at 1.5 mg/h. This enabled the patient to feel significantly more comfortable and begin advancement with passive physical therapy. While his acute stump and phantom pain were completely abated, he continued to experience nonpainful phantom limb sensations. Surgical and nursing staff members were educated about the specifics of managing an intrathecal infusion, and the catheter was marked extensively to prevent misidentification and misuse. The acute pain service served as the primary consultant for management of the intrathecal infusion and catheter care. As his physical therapy advanced to sitting in a chair, he was transitioned from the hydromorphone patientcontrolled analgesia to oral analgesic medications on POD 3. On POD 4, the intrathecal catheter infusion was stopped and he was able to further advance his activity to mobility exercises with a walker. After discontinuing the intrathecal infusion, he was discharged on the evening of POD 4 with mild to moderate tolerable pain (NRS 2–5) receiving an oral regimen of oxycodone, acetaminophen, and gabapentin. Two months postoperatively, the patient described minimal to moderate intermittent and nonpainful foot sensation consistent with phantom limb sensations. He also described occasional NRS 4 phantom limb pain that he felt to be manageable with oral medications of hydrocodone– acetaminophen (approximately 2–4 tablets/d), gabapentin 600 mg 3 times a day, and cyclobenzaprine 10 mg 3 times a day. Additionally, he is pursuing mirror box therapy as an adjuvant treatment to further reduce the frequency and intensity of the occasional painful phantom limb episodes.
DISCUSSION
Major limb amputation is an invasive surgical procedure associated with a frequent incidence of postoperative pain and a high likelihood of developing chronic stump and/or phantom pain.6,7,11 Kehlet et al.2 have postulated several risk factors associated with the development of chronic pain: preoperative pain, acute postoperative pain, invasiveness of surgery, genetic susceptibility, young age, sex, and psychosocial factors (such as catastrophization). Our patient was at high risk for the development of chronic pain due to preoperative pain at the slow-healing biopsy site (likely related to diabetes), severe acute postoperative pain, invasive surgery, and the patient’s feelings of hopelessness after multiple unsuccessful therapies. Thus, the patient, anesthesia team, surgical team, and acute pain service established that comprehensive pre- and postoperative pain coverage was an imperative goal to limit the risk of developing chronic phantom limb and stump pain.
A & A case reports
The pathophysiology of phantom limb pain has been broadly categorized as involving supraspinal, spinal, and peripheral mechanisms that suggest corresponding mechanism-directed therapies.16 With previous studies suggesting that epidural anesthesia can achieve adequate pain control and reduce the risk for chronic pain,9,11 an epidural anesthetic and analgesia plan was devised to minimize preoperative and postoperative pain. This was initiated in the preoperative period before the start of surgery. We acknowledged that a longer period of treatment (48 hours preoperatively) as seen in study by Karanikolas et al.9 may have provided further benefit; however, this was limited by the urgent scheduling for surgical intervention. After an uneventful intraoperative course, many would consider epidural infusion (spinal-directed therapy), intraoperative neural sheath injection (peripheral-directed therapy), and IV opioid therapy (supraspinal-directed therapy) to be adequate techniques to obtain a moderate degree of analgesia. When these primary modalities fail as was the case with this patient, management can be very difficult for both the patient and the care providers. Uncontrolled stump and phantom limb pain was unrelieved by increased epidural anesthesia dosing, escalating liberalization of opioid therapy, and non-opioid adjuvant therapy and led to both a reevaluation of the failed therapies and progression to alternative modalities in the context of evolving postoperative pain. Regional anesthesia (peripheral-directed therapy) was chosen as the next mainstay of analgesia because of realtime ultrasound guidance, a low risk of procedure-related complications, and minimal need to change the patient’s position. Replacing the epidural catheter was considered, but decided against due to the patient’s inability to remain still in the lateral decubitus or sitting position and his lack of confidence in epidural anesthesia from the previous night. The failure of the regional nerve blocks resulted in a deliberation between repeating the failed blocks and proceeding to a more aggressive therapy, in this case an intrathecal catheter infusion. While the use of an intrathecal infusion has been described, it is uncommon as a treatment modality due to its associated risks of postspinal puncture headaches, backache, significant cardiovascular changes, and neurologic injury.17 The decision to proceed required an extensive discussion among the patient, surgical team, acute pain team, and nursing staff to align the goals of care and minimize potential risks. In this case, the intrathecal infusion provided a substantial level of analgesia and also substantially changed the patient’s clinical scenario by establishing lasting relief, improving his mood, increasing his interactions with hospital care providers, and ultimately breaking the potential cycle of catastrophization. Due to the surgical and acute pain services’ concern that the patient’s clinical course and risk factors would result in the development of chronic phantom and stump pain, the patient was recommended to continue care with chronic pain management physicians and mirror box therapy (as an adjuvant supraspinal-directed therapy) to further limit long-term and episodic phantom limb pain. Although the etiology of phantom limb syndrome remains unknown, Ramachandran and Hirstein’s theory of the dissociation18 between the somatosensory cortex and the peripheral somatosensory system remains a leading theory as to why mirror box therapy has been effective.
August 1, 2014 • Volume 3 • Number 3
This case represents an example of how the goals of minimizing pre- and postoperative pain in a high-risk patient can be exceedingly difficult to accomplish. When traditional modalities are unsuccessful, we recommend rapid and vigorous reevaluation and discussion among the patient and care providers regarding the goals of care and the related risks and benefits of alternative therapies. In our patient, an intrathecal infusion provided superior and lasting analgesia against the uncontrolled escalation of phantom limb and stump pain in both the acute postoperative phase and longterm recovery period. E REFERENCES 1. Jensen TS, Krebs B, Nielsen J, Rasmussen P. Immediate and long-term phantom limb pain in amputees: incidence, clinical characteristics and relationship to pre-amputation limb pain. Pain 1985;21:267–78 2. Kehlet H, Jensen TS, Woolf CJ. Persistent postsurgical pain: risk factors and prevention. Lancet 2006;367:1618–25 3. Nikolajsen L, Ilkjaer S, Krøner K, Christensen JH, Jensen TS. The influence of preamputation pain on postamputation stump and phantom pain. Pain 1997;72:393–405 4. Weiss SA, Lindell B. Phantom limb pain and etiology of amputation in unilateral lower extremity amputees. J Pain Symptom Manage 1996;11:3–17 5. Owings MF, Kozak LJ. Ambulatory and inpatient procedures in the United States, 1996. Vital Health Stat 13 1998:1–119 6. Nikolajsen L, Jensen TS. Phantom limb pain. Br J Anaesth 2001;87:107–16 7. Ballantyne JC, Cousins MJ, Giamberardino MA, Jamison RN, McGrath PA, Rajagopal MR, Smith MT, Sommer C, Wittink HM. Clinical updates: chronic pain after surgery or injury. Int Assoc Study Pain 2011;19:1–5 8. Bach S, Noreng MF, Tjéllden NU. Phantom limb pain in amputees during the first 12 months following limb amputation, after preoperative lumbar epidural blockade. Pain 1988;33:297–301 9. Karanikolas M, Aretha D, Tsolakis I, Monantera G, Kiekkas P, Papadoulas S, Swarm RA, Filos KS. Optimized perioperative analgesia reduces chronic phantom limb pain intensity, prevalence, and frequency: a prospective, randomized, clinical trial. Anesthesiology 2011;114:1144–54 10. Woolf CJ, Chong MS. Preemptive analgesia–treating postoperative pain by preventing the establishment of central sensitization. Anesth Analg 1993;77:362–79 11. Hanley MA, Jensen MP, Smith DG, Ehde DM, Edwards WT, Robinson LR. Preamputation pain and acute pain predict chronic pain after lower extremity amputation. J Pain 2007;8:102–9 12. Dahm PO, Nitescu PV, Appelgren LK, Curelaru ID. Long term intrathecal infusion of opioid and/or bupivacaine in the prophylaxis and treatment of phantom limb pain. Neuromodulation 1998:111–28 13. Jacobson L, Chabal C, Brody MC, Mariano AJ, Chaney EF. A comparison of the effects of intrathecal fentanyl and lidocaine on established postamputation stump pain. Pain 1990;40:137–41 14. Borghi B, D’Addabbo M, White PF, Gallerani P, Toccaceli L, Raffaeli W, Tognù A, Fabbri N, Mercuri M. The use of prolonged peripheral neural blockade after lower extremity amputation: the effect on symptoms associated with phantom limb syndrome. Anesth Analg 2010;111:1308–15 15. Fisher A, Meller Y. Continuous postoperative regional analgesia by nerve sheath block for amputation surgery–a pilot study. Anesth Analg 1991;72:300–3 16. Hsu E, Cohen S. Post-amputation pain: epidemiology, mechanisms, and treatment. J Pain Res 2013;6:121–36 17. Miller RD, Eriksson LI, Fleisher LA, Wiener-Kronish GP, Young WL. Chapter 51: Spinal, epidural, and caudal anesthesia. In: Miller RD, ed. Miller’s Anesthesia. 7th ed. Philadelphia, PA: Churchill Livingstone Elsevier, 2009:1618–28 18. Ramachandran, VS, Hirstein W. The perception of phantom limbs. Brain 1998;121:1603–30
cases-anesthesia-analgesia.org
37
