Complications of Interventional Therapies Dr K E Khor Department of Pain Management Prince of Wales Hospital SYDNEY
ASA Closed Claims study (Chronic Pain) in claims over time 2% (1970 s) to 10% (1990 s) size of claims $25 000 (1970-80 80 s) to $70 000 (1990 s) claims from permanent & disabling injury 17% (1970-80 80 s) vs. 30% (1990 s) 97% of claims from invasive procedures Fitzgibbon DR et al. Anesthesiology 2004;100:98-105
ASA Closed Claims study (Chronic Pain) n=273 Outcomes from therapies resulting in claims Nerve injury (including spinal cord injury) (23%) Neuraxial (n=161) > peripheral (n=110) Temporary injury 73%, permanent nerve damage 13% Pneumothorax (21%) Infection (13%) Meningitis, epidural abscess, osteomyelitis Death / brain damage (9%) Cardiorespiratory collapse, delayed respiratory depression Headache (8%) Increased pain / no relief (8%) Fitzgibbon DR et al. Anesthesiology 2004;100:98-105
ASA Closed Claims study (Chronic Pain) Procedures accounting for claims Epidural steroid injection (40%) Peripheral nerve blocks (10%) Autonomic nerve blocks (10%) Maintenance of analgesic devices (7%) Trigger point injections (6%) Ablative procedures (6%) Implantation or removal of pumps / stimulators (4%) Fitzgibbon DR et al. Anesthesiology 2004;100:98-105
Epidural steroid injection Neurological injury
Epidural steroid injections: complications Nerve & spinal cord injury Others Pain Non postural headache Insomnia vasovagal Facial flushing / generalized erythema Retinal haemorrhage Subcapsular cataract Hiccups Botwin KP 2002 Abrams SE 1995 Arachnoiditis / cauda equina syndrome / nerve root injury Intra-cord injection Epidural haematoma Infections Intradural / epidural abscess Meningitis discitis osteomyelitis Dura puncture & headache Pharmacologic side-effects steroids local anaesthetics opioids
Epidural haematoma & abscess after epidural steroid injection cause Epidural haematoma (Stoll A 2002) Disruption of epidural arteries or dorsal venous plexus Epidural abscess (Huang RC 2003) Innoculation from cutaneous flora haematogenous seeding; Staph Aureus / epidermidis / others Predisposing factors Coagulopathy, full anticoagulant therapy, ankylosing spondylitis Diabetes, metastatic carcinoma, neutropaenia, oral steroid, previous infection Presence of indwelling catheters outcome Magnitude & duration of cord compression Site (cervical) Persistent deficits in 60% of P treated surgically and 30% of P treated medically Site (lower thoracic & lumbar) incidence 1:190 000 following epidural anaesthesia. 1:800 (Phillips JMG 2002) to 1:1930 (Wang LP 1999) following postoperative analgesia prevention Directed at coagulopathy Meticulous sterile technique esp. to skin preparation
Other complications from intraspinal steroid injections Neurotoxicity (Arachnoiditis, cauda equina syndrome, aseptic meningitis) from repeated IT Methylprednisolone (? Polyethylene glycol, benzyl alcohol) None from epidural steroid injection Unrecognised IT placement Neurologic injury from direct spinal cord trauma Direct cord injection with medications Risk cervical & thoracic levels ; ± sedation; large disc herniation displaces cord posteriorly Pharmacologic effects Steroids Local anaesthetics IT injection high spinal anaesthesia [6 cases in closed claims of death/brain n damage from accidental IT injection] Opioids Delayed respiratory depression from morphine coadministered with steroid [3 cases of brain damage/death in closed claims study] Fitzgibbon DR et al. Anesthesiology 2004;100:98-105 Abram SE, O Connor TC. Reg Anesth 1996;21:149-62 Tripathi M et al. Anesth Analg 2005;101:1209-11
Transforaminal steroid injection Neurological injury
Cervical transforaminal steroid injection Treatment of cervical radicular pain ± radiculopathy Technique Rathmell JP, Bogduk K. Anesthesiology 2004;100:1595-1600
Cervical transforaminal steroid injection: severe neurological complications Nerve root trauma Dural puncture spinal anaesthesia Reaction to radiocontrast agents Spinal cord / brain stem infarction
Cervical transforaminal steroid injection: spinal cord / brainstem infarction Brouwers (2001): R C6 block (triamcinolone) anterior spinal artery syndrome below C3 Ludwig (2005): L C6 block (triamcinolone) vascular infarction of spinal cord C2-5 Beckman (2006): R C8 block (methylprednisolone) cerebellar infarction & brainstem herniation Tiso (2004): R C6 block (triamcinolone) cerebellar & occipital cortex infarction Rozin (2003): L C6 block (methylprednisolone) massive cerebral oedema & death Perforation of vertebral artery dissection, luminal occlusion & thrombosis cerebral oedema / haemorrhage & herniation
Cervical spinal cord / brainstem infarction: mechanism of injury Inadvertent intra-arterial arterial injection into cervical radicular artery Occlusion of vessels by particulate steroids embolus, sludging methylprednisolone > triamcinolone >> bethamethasone) Compromise of anterior spinal artery? other mechanisms Baker R et al. Pain 2003;103:211-5 Tiso RL et al. Spine J 2004;4:468-74
Macroscopic appearance of corticosteroids Illustration of arterial dimension Particle size > 100 micron: MPA 8.6% TA 3.7% BSP nil Tiso RL et al. Spine J 2004;4:468-74
Possible preventative actions: Needle always in contact with posterior wall of foramen (Baker et al 2003, Rathmell 2004) Prevent movement of needle use of minimal extension tubing?use of blunt needles Test injection of contrast medium under real-time imaging (Karasek & Bogduk 2004) Use of DSA (Baker et al 2003) Injectate local anaesthetic before corticosteroid (Karasek & Bogduk 2004) use of less or non-particulate steroid (Rathwell 2004) Delivered through an epidural catheter (Larkin2003) Aspiration not reliable for intra-arterial arterial injection (Furman 2003)
Intravascular penetration during transforaminal cervical injection Rate of intravascular injections = 19.4% Prediction of vascular injection from flash or positive blood aspiration N=504 Positive vascular injection by fluoroscopic guidance Positive flash or blood aspirate Negative vascular injection by fluoroscopic guidance 45 (TP) 12 (FP) Negative flash or blood aspirate 53 (FN) 394 (TN) Sensitivity = 45.9% Specificity = 97.0% Furman MB et al. Spine 2003;28:21-25
Paraplegia after transforaminal nerve blocks in lumbosacral regions Paraplegia after lumbosacral nerve root blocks Reported: Left L1, Left L3, Right L3,Left S1 Caused by injury to artery of Adamkiewicz Undetected intraarterial injection of a particulate steroid injection embolization Direct injury thrombosis Houten JK, Errico TJ. Spine J 2002;2:70-5 Huntoon MA, Martin DP. Reg Anesth Pain Med 2004;29:494-5
Neurolytic coeliac plexus blocks Neurological injury
Neurolytic coeliac plexus block Indications: Pain of intra-abdominal abdominal malignancies esp. carcinoma of pancreas Non-cancer cancer pain from chronic pancreatitis Classic techniques: retrocrural anterocrural transaortic All equally effective Ischia S et al. Anesthesiology 1992;76:534-540
Neurolytic coeliac plexus block: severe complications from needle misplacement Neurological (1% 1% - Eisenberg E 1995) Neuralgia [1% 1% -Thompson G 1977; 1.4% Owitz; 7.7% Impotence [3% Loss of sphincter control [0.1% Paresis of lower limbs [0.15% Vascular Aortic dissection Retroperitoneal haematoma Others Pneumothorax Pleural effusion Kidney perforation rhabdomyolysis Thompson G 1977; 1.4% Owitz; 7.7% -Black A 1973] 3% - Black A 1973] 0.1% - Davies D 1993] 0.15% - Davies D 1993] Fugère F, Lewis G. Can J Anaesth 1993;40:954-63
Paraplegia from neurolytic coeliac plexus block Author Approach X-ray / contrast Solution Neurological Cause Galizia 1974 Prone Posterior L1 landmarks No Phenol 5mls R; 1mL L L1 paraplegia Spinal cord ischaemia Thompson 1977 Left Lateral Posterior No Alcohol 50% 50 mls Leg paralysis Nerve root injury Lo 1982 Prone Posterior L1 Yes Alcohol50% 40 mls T11 sensorimotor Partial Recovery @ 1 mth Spinal cord ishaemia - spasms Cherry 1984 Left lateral Posterior L1 Yes Alcohol 100% 25 mls T11-12 12 paraplegia Spinal cord ishaemia Woodham 1989 Prone Posterior L1 Yes Alcohol 90% 30 mls T11-12 12 paraplegia Spinal cord ischaemia Van Dougan 1991 Prone Posterior L1 Yes Alcohol 96% 10 mls X2 L1 paraplegia Spinal cord ischaemia Jabbal 1992 Prone Posterior Yes (no contrast) Alcohol 50% 40 mls L1-5 5 paraparesis Resolved (10 days)? Uncertain cause De Conno 1993 Prone Posterior T12- L1 Yes Alcohol 50% 25 mls, 95% 10 ml T8 paraplegia spinal cord ishaemia Traycroff 1993 Prone Posterior transaortic L1 Yes Alcohol 50% 20 mls T7 paralysis Resolved (21 days) Spinal cord ischaemia - vasospasm Wong 1995 Prone Posterior T12- L1 No Alcohol 50% 25 mls X2 T8 paralysis Resolved (90 min) Spinal cord ischaemia vasospasm Hayakawa 1997 Intraoperative direct vision L1 No Alcohol 99.5% 20 mls T11 paraplegia Spinal cord ischaemia Kumar 2001 Prone Posterior T12- L1 Yes Alcohol 95% 12.5 mls X2 T12 L4 paraparesis Resolved (30 days) Spinal cord ischaemia - vasospasm
Mechanism of neurological injury during neurolytic CPB Direct nerve injury from needle or injection into: intrathecal or epidural space thoracolumbar nerve roots lumbar plexus superior hypogastric plexus Interruption of blood flow to spinal cord: vascular injury (needle / neurolytic) thrombosis spasm to major radicular artery
Reduced risk & impact of severe neurological complications of neurolytic CPB Will not prevent: Fluoroscopy & use of contrast agents Prior aspiration Transcrural & transaortic technique Meticulous technique Unknown:? Use of CT scan? Performing block with R needle? Alcohol concentration < 50% Only used for malignant conditions? Splanchnic plexus RF neurotomy Thompson 1997 Woodham 1989 Wright 1989
Nerve blocks & Injections Pneumothorax
Pneumothorax: factors associated with claims Types of blocks / injections Intercostal [ 0.082-2% 2% ] Trigger point [? ] Stellate [? ] Upper extremity [ 0.6-6% 6% Kulenkampff s s supraclavicular block ] Diagnosis after discharge (>50% of claims) Chest tube placements (>50% of claims) Recommendations Consent Low threshold for CXR P instructions on S&S & contact no. Fitzgibbon DR et al. Anesthesiology 2004;100:98-105
Intrathecal drug delivery systems
Intrathecal drug delivery systems - Drug related Drug-specific side-effects effects Endocrine disturbance Hyperalgesia complications Procedure related Infection of system ± meningitis Spinal haematoma Csf leak Spinal cord trauma Catheter related Kinking, occlusions, breaks, migration, disconnection Intrathecal granuloma Pump related Pump failure Pump torsion Refill errors Reprogramming errors Kamran S, Wright BD. Neuromodulation 2001 Naumann C, et al. Neuromodulation 1999
Drug effects: Endocrine effects of long term IT opioids Hypothalamic Factor Ant Pituitary hormone Target organ Target gland Effects CRH ACTH Adrenal cortex glucocorticoids androgens Potential for Addisonian crisis GnRH LH Ovary, testes oestradiol, progesterone testosterone Libido Amenorrhea impotence TRH TSH Thyroid thyroxine Dopamine Prolactin Breast GHRH Somatostatin GH All tissues IGF-I Λ muscle strength & metabolism QOL & life expectancy Abs R et al. J Clin Endocrinol Metab 2000;85:2215-2222
Endocrine effects of long term IT opioids Endocrine dysfunction Hypogonadotropic hypogonadism (M>60%;W100%) Central hypocorticism 15% 10% 10% GH deficiency 10% No relationship to dose of opioids & duration of administration IT > oral opioids Treatment Replacement therapies Withdrawal of opioids Abs R et al. J Clin Endocrinol Metab 2000;85:2215-2222
Infection Surgical wound Pump site, superficial or deep catheter tract 0-9% [ vs long term externalized epidural catheter ~4.3%] Staph aureus or staph epidermidis Management Intraspinal infection Meningitis: low incidence <1% Myelopathy / transverse myelitis: rare Epidural abscess: rare (<<1:10 000) Management Pump refill No documented infection during 890 refills (manufacturer s s protocol) Co-morbid infections in other parts not a risk for device contamination tion Ubogu EE et al. Reg Anesth Pain Med 2003;28:470-4 Kamran S et al. Neuromodulation 2001;4:111-5 Dario A et al. Neuromodulation 2005;8:36-9
Spinal cord trauma: Intramedullary placement of spinal catheter Rare (3 case reports) Presents with early onset neurological symptoms (deficits, pain) Worsened by intramedullary infusion Investigations MRI scan CT myelogram Slavin KV. Neuromodulation 2006;9:94-99 Huntoon MA et al. Anesth Analg 2004;99:1763-1765 Harney D, Victor R. Reg Anesth Pain Med 2004;29:606-609
Intramedullary placement: Management & Prevention Management Cessation of infusion & removal of catheter Prognosis Resolution Residual neurological deficits Posttraumatic syrinx formation Prevention Catheter insertion at L2/3 or L3/4 level Check CSF flow after catheter placement High vigilance Thorough investigation before irreversible deficits occur Slavin KV. Neuromodulation 2006;9:94-99 Huntoon MA et al. Anesth Analg 2004;99:1763-1765 Harney D, Victor R. Reg Anesth Pain Med 2004;29:606-609
Catheter related complications: Intrathecal granuloma Prevalence 3% in a surveillance series (80% asymptomatic) Duration of infusion 25 months (0.5-120 120 months) Presentation Loss of analgesia Frequent need for dose escalation New onset radicular pain / paraesthesias Spinal cord neurological deficits Drugs implicated Morphine ± adjuvants 10mg/day (70%) ; 25mg/mL (85%) Hydromorphone Fentanyl. Sufentanil, tramadol Yaksh TL et al. Pain Medicine 2002;3:300-312. Deer TR. Pain Physician 2004;7:225-228.
Intrathecal granuloma - management Vigilance, high index of suspicion Asymptomatic Small masses found on analgesic efficacy or subjective symptoms No significant neurological compromise Progressive neurological deficits Large inflammatory mass on imaging Change to different opioid ±Adjuvant Close follow-up Serial radiological images Stop infusion Catheter revision: Move catheter caudally 1-2 segments Catheter replacement: To a lower segment Immediate admission Stop infusion Neurosurgical consult Surgical decompression + removal Infused different drug post-op Hassenbusch S et al. Pain Medicine 2002;3:313-323
Preventative strategies for intrathecal granuloma Intrathecal drug Alternatives to morphine Keep drug dose as low as possible for as long as possible Opioid sparing adjuvants bupivacaine / clonidine Drug concentration Keep opioid concentration as low as possible (morphine 40mg/mL) Placement of catheter (?) Lumbar thecal sac below conus medullaris Hassenbusch S et al. Pain Medicine 2002;3:313-323
Pump related: drug refill errors Wrong refill site (other than pump reservoir) CSF access port Pump pocket Subcutaneous tissue Overdose of refill medications Baclofen Opioids, Clonidine, bupivacaine Prevention Qualified & well trained staff Established refill policy Management Prompt recognition Aspiration Observation Supportive care & resuscitation Antagonist Coyne PJ, et al. J Pain Symptom Manage 2004
Spinal cord stimulator
Spinal cord stimulator: complications Related to procedure Post-dural dural puncture headache (11% - Kemlar MA et al 2000) Nerve injury Epidural abscess (rare 1 case reported in series of 830P) Epidural haematoma (2 reported cases in literature) Wound infection (~4.5%) Seroma Pain at implant site (~6%) Related to device (~43%) Related to electrode Electrode migration Fracture of lead or extension Painful stimulation Related to pulse-generator / receiver Psychological Device flipping Device malfunction Skin burns (from rechargeable IPG) Allergic reaction to device Turner JA et al. Pain 2004;108:137-147
Psychological issues complicating spinal cord stimulator implantation Conversion disorder (Parisod E et al. Anesth Analg 2003) Conversion locked-in syndrome (Han D et al. Anesth Analg 2007) Conversion disorder mimicking Dejerine-Roussy syndrome (Ferrante FM et al. Reg Anesth Pain Med 2004) Panic attacks (Sheu R et al. Anesth Analg 2006) Induction of schizophreniform disorder (Zdanowicz N et al. Psychosomatics 1999)
Summary Severe catastrophic complications are uncommon All common procedures performed by interventional pain specialist represented in closed claims Most common ESI Most feared irreversible neurological injury Mechanisms of injury related to vascular injury / thrombosis / embolisation to critical perfusion vessels (needle, particulate steroids, neurolytic agents) Direct space occupying lesions Direct trauma to central nervous system Preventative strategies not entirely fool-proof Meticulous imaging, proper training, reevaluate utility of treatment, patient consent & post-procedural procedural information Other feared complications Central nervous system infections, pneumothorax