C h ro n i c Pa i n : Magdalena Anitescu,

Anesthesia for Procedures

MD, PhD

KEYWORDS  Interventional pain-relieving procedures  Anesthesia for pain interventions  Complications in pain management KEY POINTS  Pain management is an evolving field of medical specialty that uses increasingly complex procedures to diagnose and treat refractory and unrelenting chronic pain.  To increase patient satisfaction and relieve anxiety associated with advanced painrelieving procedures, physicians use anesthetic techniques ranging from local anesthetic infiltrations to general anesthesia.  Balancing patient safety and comfort during anesthesia for pain-relieving procedures is becoming essential for the successful treatment of various and difficult pain conditions.

INTRODUCTION

Whether pain is chronic or arises immediately after a surgical intervention, it is the symptom most feared by patients. In particular, patients suffering from chronic pain are often afraid of embracing interventional procedures fearing aggravation of their symptoms. Therefore, in order to alleviate anxiety associated with various pain techniques and to improve patient satisfaction while treating chronic pain syndromes, pain physicians may use various anesthetic techniques for interventional pain-relieving procedures. This article describes the anesthesia techniques commonly used in pain practices. HISTORY OF INTERVENTIONAL PAIN MANAGEMENT

Although medical management of pain has been used for thousands of years, interventional techniques to treat chronic, refractory, or unrelenting pain are much more recent, concomitant with the discovery, development, and advances in neural blockade and regional analgesia. Koller’s discovery in 1884 that cocaine numbs the tongue1,2 prompted physicians to use this product in a variety of interventional techniques aimed to relieve pain, such as caudal epidural injections (Cushing,3 1902), trigeminal ganglion block (Schloesser,4 1903), spinal anesthesia, and epidural analgesia using loss of resistance techniques. Identifying specific pain generators was the next step in the evolution of interventional pain management as a medical subspecialty. Disclosure: The author has no financial interest in any of the materials discussed. Pain Management Fellowship Program, Department of Anesthesia and Critical Care, University of Chicago Medical Center, 5841 South Maryland Avenue, MC 4028, Chicago, IL, USA E-mail address: [email protected] Anesthesiology Clin - (2014) -–http://dx.doi.org/10.1016/j.anclin.2014.02.001 anesthesiology.theclinics.com 1932-2275/14/$ – see front matter Ó 2014 Elsevier Inc. All rights reserved.

2

Anitescu

Diagnostic blockade by administering a low dose of local anesthetic in a specific region via an interventional procedure to pinpoint the source of pain was first introduced in 1924 by von Gaza5 who tried to identify pain arising from sympathetic or sensory nerves. Others attempted to identify specific sources of pain using procaine.6 Bonica’s extensive experience with diagnostic blockade and his and others’ constant quest for multidisciplinary interventional pain treatments, coupled with advances in the understanding of clinical anatomy and the structural basis of pain through Bogduk and colleagues’7 more recent studies, made pain interventions develop into complex, more advanced, lengthy procedures. Often those complex procedures required deep levels of sedation or occasionally general anesthesia. ANESTHESIA TECHNIQUES IN OFF-SITE LOCATIONS

The anesthetic techniques that are used for interventional pain-relieving procedures range from minimal or no sedation to general anesthesia. With the increase in the number and complexity of pain-relieving procedures, more are now performed in offices and freestanding ambulatory surgery centers where anesthesiologists are available for care. Although anesthesia is not needed for simple pain interventions, a constant trend to improve patient satisfaction with pain relief prompts physicians to use sedation more often than in previous decades.8 In an already ailing patient population, anxiolysis and amnesia offered by sedation may distinguish one physician’s practice from another. Sedation analgesia for a procedure relies on anxiolytics, sedatives, hypnotics, or dissociative medications to decrease anxiety, pain, or movement in patients.9 Although practice guidelines may differ in different regions,10 the American Society of Anesthesiologists (ASA) and The Joint Commission consider sedation a continuum and recognize 3 levels of sedation plus general anesthesia (Table 1). The most common agents used for sedation are opioids and benzodiazepines for their anxiolytic and amnesic effects. Sedation can relax muscles and maintain analgesia (Table 2).11 INTERVENTIONAL PAIN-RELIEVING PROCEDURES

Following an ascending trend in complexity and difficulty, interventions performed by trained pain physicians can range from a simple procedure in the office to a surgical case in an operating room. To align a patient’s expectations with the complexity of interventional pain-relieving procedures, physicians administer anesthesia to limit the anxiety, pain or emotional distress in patients who suffer from chronic pain. A brief Table 1 Description of levels of sedation Type of Sedation

Definition

Minimal sedation

Patients are in drug-induced state of anxiolysis Patients respond normally to verbal commands

Moderate sedation (conscious sedation)

Patients have drug-induced depression of consciousness Patients respond purposefully to voice or tactile stimulation No interventions are needed to maintain patients’ airway

Deep sedation

Patients have drug-induced depression of consciousness Patients cannot be easily aroused Patients respond purposefully after repeated or painful stimulation Ventilatory function may be impaired

From Jones DR, Salgo P, Meltzer J. Videos in clinical medicine. Conscious sedation for minor procedures in adults. N Engl J Med 2011;364:e54; with permission.

Table 2 Comparative spectrum of pharmacologic effects Drug

Anxiolysisa

Sedation

Hypnosis

Analgesia

Amnesia

Anesthesia

Dependency

Methohexital

0

1

1

0

1

1

1

1

1

1

0

1

1

1

1

1

1

0

1

1

1

Propofol

0

1

1

0

1

1

1

Ketamine

0

0

0

1

1

1/D

0

Fentanyl

0

1

1

1

0

1

1

Remifentanil

0

1

1

1

0

1

1

Dexmedetomidine

0

1

1

1

1

S

0/A

Abbreviations: A, attenuates withdrawal symptoms from barbiturates, benzodiazepines, opioids; D, dissociative anesthetic state; S, anesthetic sparing effect; 1, produces effect; 0, no effect. a Possessing receptor specificity for effect. Data from Smith HS, Colson J, Sehgal N. An update of evaluation of intravenous sedation on diagnostic spinal injection procedures. Pain Physician 2013;16(Suppl 2):SE217–28.

Chronic Pain: Anesthesia for Procedures

Diazepam Midazolam

3

4

Anitescu

description of common pain procedures and their anesthetic requirements is shown in Table 3. Most in-office procedures (trigger points, joint injections, bursa injections) can be tolerated easily by patients without sedation and sometimes without skin infiltration by local anesthetic. Infusion treatments with lidocaine or ketamine may simply require ASA standard monitoring because of their side effects. Intravenous lidocaine, which blocks sodium channels indiscriminately, has been effective for several conditions: trigeminal neuralgia, diabetic neuropathy, fibromyalgia, cancer pain resistant to opioid therapy, and pain from spinal cord injury or central pain.12 Because lidocaine is a potent antiarrhythmic and can be associated with seizure activity, those procedures are performed by an anesthesiologist according to the ASA standards for monitored anesthesia care. Monitoring takes place for the duration of the infusion and recovery period. The author’s institutional protocol is described in Box 1. Ketamine, once a battlefield anesthetic, interacts with a variety of receptor subtypes, including opioid, N-methyl-D-aspartic acid (NMDA), g-aminobutyric acid type A and alpha-amino-3-hydroxy-5-methyl-4- isoxazole propionate, that act in chronic pain states. Acting as an antagonist on centrally located NMDA receptors, ketamine is effective against neuropathic pain, cancer pain, fibromyalgia, opioid tolerance, diabetic neuropathy, and headache.13,14 Because ketamine can produce hallucinations, Table 3 Common Interventional pain procedures and their Anesthetic Management Additional Imaging/ Fluoroscopy

Additional Imaging/ Ultrasound

Types of Sedation/ Anesthesia None None/local skin infiltration None/minimal/ moderate sedation

Locations

Procedures

Office

Trigger points Major/minor joint injections/ bursa injections

No No

No/yes No/yes

Infusions (lidocaine/ketamine)

No

No

Routine procedures: Epidural steroid injections, transforaminal epidural steroid injections, medial branch nerve blocks, and so forth Complex procedures: sympathetic chain blocks, discographies, gasserian ganglion blocks and RF, minimally invasive lumbar decompression

Yes

Yes/no

Local skin infiltration,  minimal sedation

Yes

No

Local infiltration,  minimalmoderate sedation

Yes

No

Local infiltration, deep sedation, general anesthesia, regional anesthesia

Pain clinic procedure room/ ambulatory surgery center

Surgery center

Kyphoplasty, spinal cord stimulator, drug delivery system insertion

Abbreviation: RF, radiofrequency.

Chronic Pain: Anesthesia for Procedures

Box 1 University of Chicago protocol for lidocaine infusion Consultation  Obtain baseline electrocardiogram (EKG) and cardiac history.  Evaluate patients for arrhythmias before scheduling the procedure. Day of Procedure  Assess patients for fasting and alertness.  Determine effects of previous infusion, if any on  Pain reduction  Duration of effects  Patient function after infusion  Decrease in use of pain medication since infusion  Verify that patients have companion to accompany them home.  Obtain signed consent on the consent form. Procedure  Apply the standard monitors: blood pressure, EKG, pulse oximeter, capnograph.  Start IV access and administer 1-mg/kg lidocaine bolus over 3 to 5 minutes.  Follow with 4 mg/kg lidocaine (or 2–4 mg) administered slowly over 30 minutes (or 20– 30 minutes).  Record the following at 1, 5, 10, 15, 20, 25, and 30 minutes:  Time of administration  Blood pressure  Heart rate  Pulse oximetry  Pain score  Stop the infusion in the event of seizure activity or cardiac instability. Recovery  Patients recover within 30 to 60 minutes after the procedure.  Vital signs are monitored over 15 minutes during recovery.  At the end of the recovery period, patients are discharged from the clinic to the accompanying caregiver. Follow-up  In 4 weeks, patients return for the evaluation of treatment or repeat infusion.  The dose of lidocaine is not increased if the initial infusion was performed with 4 mg/kg over 20 minutes.

pretreatment with midazolam and sometimes with fentanyl are indicated to reduce these side effects. With these medications, most patients are mildly to moderately sedated during infusion and may take up to 1 hour to recover after treatment. These infusions may be administered in the office or in an ambulatory surgery center under the direct care of an anesthesiologist who applies ASA standard monitors. The author’s clinic protocol is described in Box 2.

5

6

Anitescu

Box 2 University of Chicago protocol for ketamine infusion Consultation  Obtain baseline electrocardiogram (EKG) and cardiac history.  Evaluate patients for arrhythmias before scheduling the procedure. Day of Procedure  Assess patients for fasting and alertness.  Determine effects of previous infusion, if any on  Pain reduction  Duration of effects  Patient function after infusion  Decrease in use of pain medication since infusion  Verify that patients have a companion to accompany them home.  Obtain signed consent on the consent form. Procedure  Apply the standard monitors: blood pressure, EKG, pulse oximeter, capnograph.  Start IV access and pretreat with  Midazolam 2 mg IV  Ondansetron 4 mg IV  Begin ketamine infusion with 0.3 mg/kg in 100-mL bag for 30 to 45 minutes.  Record the following at 1, 5, 10, 15, 20, 25, and 30 minutes:  Time of administration  Blood pressure  Heart rate  Pulse oximetry  Pain score  Depending on the patients’ vital signs and pain scores, the infusion may be extended to 60 minutes.  Stop the infusion in the event of the following adverse effects:  Hallucinations  Blood pressure increase more than 20% of baseline  Severe anxiety  Nausea  Unmanageable, symptomatic nystagmus  Most adverse effects disappear when infusion is stopped.  Assess patients for urgent management. Recovery  Patients recover within 30 to 60 minutes after the procedure.  Vital signs are monitored every 5 to 15 minutes during recovery.

Chronic Pain: Anesthesia for Procedures

 At the end of the recovery period, patients are discharged from the clinic to the accompanying caregiver. Follow-up  In 4 weeks, patients return for the evaluation of treatment or repeat infusion.  Infusion doses may be increased to 0.6 mg/kg to 1.0 mg/kg, depending on the effect of the infusion on pain scores and the patients’ function or satisfaction with pain relief.

Sedation for pain interventions that are performed in ambulatory surgery centers or in freestanding office pain clinics is inconsistent across interventional pain settings.9 In the United States, approximately 46% of interventional pain physicians recently surveyed use intravenous (IV) sedation for patients during routine lumbar steroid injections; up to 53% of the same responders use it in cervical epidural steroid injections.15 In many office anesthetizing locations, deep sedation is discouraged for routine pain-relieving procedures. For diagnostic procedures, such as discography, selective nerve root block, or medial branch nerve blocks, the added effect of opioids and benzodiazepines may alter the accuracy of the results and expose patients to unnecessary, more invasive procedures, such as radiofrequency ablation or spine surgery. Some interventional pain-relieving procedures may be performed in the operating room with patients under deep sedation, regional or general anesthesia. Among such procedures are the placement of a spinal cord stimulator and generator, implantation of an intrathecal drug delivery device, and vertebral body augmentation (VBA) with kyphoplasty (KP) or vertebroplasty (VP). The choice of anesthetic often depends on the presence or absence of serious patient comorbidities. Patients undergoing VBA are usually frail. Care is taken in positioning patients for the procedure, and neurologic status is evaluated immediately after the procedure.16–19 There is no consensus on the type of anesthesia to be used for the VBA. The number of vertebrae to be treated in addition to the consideration of patients’ comorbidities typically affect the decision. Active distention with the balloon during KP can be painful, and general anesthesia may be an option. VP may be performed with patients under sedation; however, if the number of vertebrae treated exceeds 3, a long operating time for patients in an uncomfortable position may make general anesthesia preferable. Patients’ comorbidities and age favor local anesthesia and conscious sedation. In patients with advanced chronic obstructive pulmonary disease and carbon dioxide retention, deep sedation can aggravate respiratory depression, worsen oxygenation, and increase the right ventricular afterload because of hypercapnia and pulmonary vasoconstriction. Regional anesthesia and analgesia may be a reasonable alternative for these cases. With neuraxial short-acting local anesthetic agents and small doses of neuraxial opioids, a VBA can be performed with light systemic sedation and maximum patient comfort.20–23 In the author’s institution, balloon KP is performed in the operating room to treat vertebral compression fractures. Patients are given mild sedation, and the vertebral pedicles are infiltrated with lidocaine 2% and bupivacaine 0.5%. The most feared complication of VBA is cement extravasation. With patients pain free from a general or regional anesthetic, cement leakage toward a nerve root or in a vessel can be easily masked. Using a slow injection with pastelike cement under direct fluoroscopic views from both posteroanterior and lateral positions may decrease the risk of devastating complications.

7

8

Anitescu

COMPLICATIONS RELATED TO ANESTHETIC TECHNIQUES IN INTERVENTIONAL PAIN PROCEDURES

With the constant growth in complexity and duration of interventional pain-relieving procedures, patients are often immobile for long periods. Although minimal or moderate sedation does not offer an additional risk, deep sedation techniques have produced adverse events with devastating results for patients. Despite a perfect fluoroscopic image, paresthesia from needle placement in the neuraxium may alert the physician to needle malposition. The needle is redirected or the procedure is aborted. Patients under deep sedation, however, cannot trigger this safety signal and may awaken from the procedure gravely injured. That is the reason that certain procedures benefit from patient feedback (Table 4). Airway Compromise

Among the most serious complications from conscious sedation that progress to deep sedation are respiratory and cardiovascular depression or collapse. Aggressive rescue measures are necessary immediately when such situations occur.9 For patients who are in the prone position, the ability to regain airway control is compromised, especially when sedation is administered with hypnotic agents, such as propofol, by non–anesthesia trained personnel.24 Airway compromise associated with unrecognized high doses of hypnotics during sedation can induce a seizurelike phenomenon often associated with apnea and rapid desaturation.25 If propofol is administered during a procedure, minimal to moderate sedation states should be maintained with appropriate IV doses to prevent complications (Table 5).8 Disinhibition and Agitation

No cases of paradoxic agitation and hyperactivity during minimal sedations have been described. These states are not infrequently seen during deep sedation.26 Uncontrolled movements that appear with disinhibition during neuraxial needle placement can be associated with severe and devastating permanent complications, such as cord puncture, cord compression, or worsening of an already serious spinal stenosis. Agitation caused by a benzodiazepine can be quickly reversed with flumazenil27; the so-called propofol hyperexcitable state is controlled only by awakening patients or inducing general anesthesia. In those situations, more damage can be done making propofol a poor choice for these procedures.

Table 4 Interventional procedures in which patient feedback is valuable Procedure Therapeutic

Diagnostic

Epidural injections (especially cervical)

Selective nerve root block

Intrathecal catheter placement

Facet joint injections (especially cervical)

Spinal cord stimulator placement

Discography

Sympathetic blocks Intradiscal ablations Adapted from Prager JP, April C. Complications related to sedation and anesthesia for interventional pain therapies. Pain Med 2008;9(Suppl 1):S121–7; with permission.

Chronic Pain: Anesthesia for Procedures

Table 5 Uses and dosages of propofol Clinical Use

Dose

Induction of general anesthesia

Bolus: 1.0–2.5 mg/kg IV; dose reduced in elderly

Maintenance of general anesthesia

Infusion: 50–150 mcg/kg/min IV, combined with opiates or nitrous oxide

Sedation

Infusion: 25–75 mcg/kg/min IV

Antiemetic

Bolus: 10–20 mg IV; can repeat q 5–10 min Infusion: 10 mcg/kg/min

Adapted from Prager JP, April C. Complications related to sedation and anesthesia for interventional pain therapies. Pain Med 2008;9(Suppl 1):S121–7; with permission.

Predisposition to Neural Injury

Despite the safety of needle placement under fluoroscopic visualization during pain interventions, complications from malpositioning the needle within the spinal cord continue. An analysis of closed claims in anesthesiology showed that claims associated with chronic pain cases are increasing, surpassing obstetric anesthesia claims (Fig. 1). Among interventional pain procedures, cervical epidural steroid injections are associated with the most severe outcomes from needle malposition. In an analysis of the closed claims data from 2005 to 2008, Rathmell and colleagues28 found that unfavorable outcomes from cervical interventions were more severe than adverse outcomes from all other interventions (Fig. 2). In-depth analysis of the cases in malpractice claims showed that a traumatic spinal cord injury was present more often when patients had received deep sedation or general anesthesia or were unresponsive during the procedure.29 Many patients undergoing interventional pain-relieving procedures, especially neuraxial injections, have spinal stenosis and are at risk for a severe neurologic deficit if epidural pressure is increased. In awake patients, pain on epidural injection alerts the physician to decrease the amount of medication or to deliver the injectate more slowly while constantly communicating with patients. In profound sleep states

Fig. 1. Proportion of obstetric, chronic pain, and acute pain claims by decade. Claims for surgical anesthesia not shown. * P80% pain relief with the ability to perform prior painful movements is used as the standard for evaluating the effect of controlled local anesthetic blocks, the diagnostic validity of cervical facet joint nerve blocks may be preserved.

Manchikanti et al, 2004 randomized, double blind

180 patients with lumbar facet joint pain

Randomization into 3 equal groups (60 per group); titration of agent 1 mL at a time; relaxed or 5 mL max given Group I: NaCl Group II: midazolam Group III: fentanyl

80% pain relief and ability to perform previously painful movements

Pain relief of >80% was noted in 2% of the patients in group I, 5% of the patients in group II, and 7% in group III. Pain relief of >50% was noted in 7% of the patients in group I, 5% of the patients in group II, and 13% of the patients in group III. There were no significant differences among the groups.

The administration of sedation with midazolam or fentanyl is a confounding factor in the diagnosis of lumbar facet joint pain in patients with chronic low back pain. However, this study suggests that if strict criteria, including pain relief and the ability to perform prior painful movements, are used as the standard for evaluating the effect of controlled local anesthetic blocks, the diagnostic validity of lumbar facet joint nerve blocks may be preserved. (continued on next page)

Chronic Pain: Anesthesia for Procedures

Study/Methods

11

12

Anitescu

Table 6 (continued ) Study/Methods

Participants

Interventions

Outcomes

Results

Conclusions

Manchikanti et al, 2006 randomized, double blind

60 patients with combined cervical facet joint pain and lumbar facet joint pain

Randomization into 3 equal groups (20 per group); titration of agent 1 mL at a time; relaxed or 5 mL max given Group I: NaCl Group II: midazolam Group III: fentanyl

80% pain relief and ability to perform previously painful movements

Overall, 50% of the patients were relaxed or sedated in the placebo group, whereas 100% of the patients in the midazolam and fentanyl groups were relaxed or sedated. As many as 10% of the patients reported significant relief (2 reported 80%) with the ability to perform prior painful movements.

Perioperative administration of sodium chloride, midazolam, or fentanyl can confound results in the diagnosis of combined cervical and lumbar facet joint pain. False-positive results with placebo or sedation may be seen in a small proportion of patients.

Abbreviations: max, maximum; NaCl, sodium chloride. Adapted from Manchikanti L, Boswell MV, Cash KA, et al. Influence of prior opioid exposure on diagnostic facet joint nerve blocks. J Opioid Manage 2008;4:351–60.

Chronic Pain: Anesthesia for Procedures

recognized. Injury to the nerve root during radiofrequency lesioning in deeply sedated patients can go undiagnosed until patients are awakened.24 Opioids, although essential in moderate sedation for their excellent analgesic effects, should be used rarely in diagnostic interventional procedures. The addition of IV fentanyl is relatively contraindicated for diagnostic procedures, such as selective nerve root block, celiac plexus block, or discography. With fentanyl added, it is unclear if pain relief is present because of the local anesthetic blockade or the IV opioid. Adding anesthetics to interventional pain-relieving procedures to relieve anxiety and to comfort patients has mixed effects. With conscious sedation, short of severe psychiatric comorbidities or a paradoxic reaction, pain-relieving interventions can be performed with significantly less risk for adverse events. In a study of 2494 patients that analyzed adverse events after conscious sedation in ambulatory spine procedures, there was no statistically significant difference in adverse events in patients who had pain-relieving procedures under local anesthetic alone or with local anesthetic and conscious sedation with midazolam (Fig. 3).30 For diagnostic procedures that require long times and immobile patients receiving moderate sedation, the proper administration of moderate sedation did not seem to influence the results of the procedure. Manchikanti and colleagues31 evaluated the effect of sedation on pain relief after diagnostic medial branch blocks in cervical and lumbar facet joints. Using identical methodology, they found no significant difference between the sedation groups (sodium chloride, midazolam, fentanyl) or between anatomic regions treated (cervical, lumbar) and concluded that IV sedation with fentanyl or midazolam does not alter a patient’s response to a diagnostic block (Table 6).9 SUMMARY

Interventional pain-relieving procedures are becoming longer and more complex. Patients with chronic, unrelenting pain are often offered interventions during which they must be motionless. Anesthetic techniques are increasingly used by pain practitioners in order to decrease patient anxiety and pain and to provide amnesia for interventional pain-relieving procedures. Varying from local anesthetic infiltrations to general anesthesia, techniques depend on the patients’ comorbidities and type of procedure. In general, routine pain interventions do not require additional sedation. When sedation is necessary, moderate sedation is preferred because patients are responsive and can alert the physician to needle malpositioning. When general anesthesia is used in vertebral augmentation procedures, frequent fluoroscopic imaging limits the possible complications from cement extravasation. As for diagnostic interventions, there is no consensus about the influence of sedation on the accuracy and validity of the diagnostic procedure performed.9 Maintaining the balance between patients’ comfort and safety influences the changes in the evolving field of pain management. REFERENCES

1. Brown DL, Fink BR. The history of neural blockade and pain management. In: Cousins MJ, Bridenbaugh PO, editors. Neural blockade in clinical anesthesia and management of pain. 3rd edition. Philadelphia: Lippincott Raven; 1998. p. 3–34. 2. Manchikanti L. The growth of interventional pain management in the new millennium: a critical analysis of utilization in the Medicare population. Pain Physician 2004;7:465–82.

13

14

Anitescu

3. Cushing H. On the evidence of shock in major amputations by cocainization of large nerve-trunks preliminary to their division. Ann Surg 1902;36:36–321. 4. Schloesser H. Heilung periphar Reizzustande sensibler und motorischer Nerven. Klin Monbl Augenheilkd 1903;41:255. 5. Von Gaza W. Die Resektion der Paravertebralen Nervenund die isolierteDurchschneidung des Ramus communicans. Arch Klin Chir 1924;133:479. 6. Steindler A, Luck JV. Differential diagnosis of pain in the low back: allocation of the source of the pain by the procaine hydrochloride method. JAMA 1938;110:106–13. 7. Bogduk N, Christoforidis N, Cherry D, et al. Epidural use of steroids in the management of back pain. Report of working party on epidural use of steroids in the management of back pain. National Health and Medical Research Council. Canberra (Australia): Commonwealth of Australia; 1994. p. 1–76. 8. Prager JP, April C. Complications related to sedation and anesthesia for interventional pain therapies. Pain Med 2008;9(Suppl 1):S121–7. 9. Smith HS, Colson J, Sehgal N. An update of evaluation of intravenous sedation on diagnostic spinal injection procedures. Pain Physician 2013;16(Suppl 2): SE217–28. 10. Jones DR, Salgo P, Meltzer J. Videos in clinical medicine. Conscious sedation for minor procedures in adults. N Engl J Med 2011;364(25):e54. 11. Colson JD. The pharmacology of sedation. Pain Physician 2005;8:297–308. 12. Marmura M, Rosen N, Abbas M, et al. Intravenous lidocaine in the treatment of refractory headache: a retrospective case series. Headache 2009;49:286–91. 13. Krusz JC. Intravenous treatment of chronic daily headaches in the outpatient headache clinic. Curr Pain Headache Rep 2006;10:47–53. 14. Patil SK, Anitescu M. Efficacy of outpatient ketamine infusions in refractory chronic pain syndromes: a 5 year retrospective analysis. Pain Med 2012;13:263–9. 15. Ahmed SU, Tonidandel W, Trella J, et al. Peri-procedural protocols for interventional pain management techniques: a survey of U.S. pain centers. Pain Physician 2005;8:182–5. 16. Kasperk C, Ingo A, Grafe IA, et al. Three-year outcomes after kyphoplasty in patients with osteoporosis with painful vertebral fractures. J Vasc Interv Radiol 2010; 21:701–9. 17. McGirt MJ, Parker SL, Wolinsky JP, et al. Vertebroplasty and kyphoplasty for the treatment of vertebral compression fractures: an evidenced-based review of the literature. Spine 2009;9:501–8. 18. Liu JT, Liao WJ, Tan WC, et al. Balloon kyphoplasty versus vertebroplasty for treatment of osteoporotic vertebral compression fracture: a prospective, comparative, and randomized clinical study. Osteoporos Int 2010;21:359–64. 19. Pflugmacher R, Taylor R, Agarwal A, et al. Balloon kyphoplasty in the treatment of metastatic disease of the spine: a 2-year prospective evaluation. Eur Spine J 2008;17:1042–8. 20. Krueger A, Bliemel C, Zettl R, et al. Management of pulmonary cement embolism after percutaneous vertebroplasty and kyphoplasty: a systematic review of the literature. Eur Spine J 2009;18:1257–65. 21. Elshaug AG, Garber AM. How CER could pay for itself –insights from vertebral fracture treatments. N Engl J Med 2011;364:1390–3. 22. Burton AW, Hamid B. Kyphoplasty and vertebroplasty. Curr Pain Headache Rep 2008;12:22–7. 23. Schofer MD, Efe T, Timmesfeld N, et al. Comparison of kyphoplasty and vertebroplasty in the treatment of fresh vertebral compression fractures. Arch Orthop Trauma Surg 2009;129:1391–9.

Chronic Pain: Anesthesia for Procedures

24. Abram SE, Francis MC. Hazards of sedation for interventional pain procedures. Anesthesia Patient Safety Foundation Newsletter; 2012. 25. Walder B, Tramer MR, Seeck M. Seizure-like phenomena and propofol: a systematic review. Neurology 2002;58:1327–32. 26. Braidy HF, Singh P, Ziccardi VB. Safety of deep sedation in an urban oral and maxillofacial surgery training program. J Oral Maxillofac Surg 2011;69:2112–9. 27. McKenzie WS, Rosenberg M. Paradoxical reaction following administration of a benzodiazepine. J Oral Maxillofac Surg 2010;68:3034–6. 28. Rathmell JP, Michna E, Fitzgibbon DR, et al. Injury and liability associated with cervical procedures for chronic pain. Anesthesiology 2011;114:918–26. 29. Metzner J, Posner KL, Lam MS. Domino KB closed claims analysis. Best Pract Res Clin Anaesthesiol 2011;25:263–76. 30. Schaufele MK, Marin DR, Tate JL, et al. Adverse events of conscious sedation in ambulatory spine procedures. Spine J 2011;11:1093–100. 31. Manchikanti L, Boswell MV, Cash KA, et al. Influence of prior opioid exposure on diagnostic facet joint nerve blocks. J Opioid Manag 2008;4:351–60.

15

Chronic pain: anesthesia for procedures.

Chronic pain is a symptom that patients fear significantly. To treat and alleviate pain, physicians perform various interventions for which patients o...
517KB Sizes 6 Downloads 6 Views