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CANCER PAIN :EFFECTIVE INTERVENTIONAL PAIN MANAGEMENT

  • Posted on- Jul 07, 2016
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Dr.Neeraj JainM.D., FIMSA, FIPP (USA)                

Senior Consultant Interventional Spine & PainSpecialist. 

Spine& Pain Clinic, Pitampura, New Delhi-110088.

Head, Department of Pain Medicine, SriBalaji Action Medical Institute, Delhi.

Incharge Pain Clinic, Action CancerHospital, New Delhi.

Incharge Pain Clinic, Max Hospital,Pitampura, New Delhi.

9810033800(M),  managepain@yahoo.comwww.spinenpain.com

 

Pain is a major symptom of cancer and occurs at all stages of thedisease. In addition, pain is usually a hallmark of progression or metastaticspread, and 65 to 85 percent of people with cancer have pain when they developadvanced disease. In 10 to 20 percent of cancer cases, pain is difficult totreat, frustrating, and poorly controlled. Currently,opioid pharmacotherapy is the principal weapon in the fight against cancerpain but when less invasive treatments are unsuccessful, invasiveinterventions should be added to optimize pain relief. Interventional painprocedures target neural and non-neural pain generators and neural blockadetechniques provide excellent pain relief for neuropathic, sympathetic,nociceptive somatic, or visceral pain. Neural blockade techniques are broadlycategorized into non-neurolytic and neurolytic blocks.

 

           fig2  

 

Non-NeurolyticBlocks

Local anesthetic and corticosteriod blocks areused to treat a variety of pain syndromes. They can also predict how a patientwill respond to neurolytic blocks. A good response to non-neurolyticinterventions usually means the patient will benefit from neurolytic proceduresas well. Fluoroscopic guidance improves the accuracy of these blocks andminimizes complications. Somatic, sympathetic, and neuropathicpain respond to local anesthetic injections or the continuous administration ofanesthetic drugs through a catheter. Intercostal nerve blocks or interpleural analgesiaare indicated in post-thoracotomy chest wall pain/intercostal neuralgia, andradiculopathy requires selective nerve root blocks or transforaminal epiduralinjections when non-invasive treatments fail. Sympathetic blocks and otherregional anesthetic techniques are employed in sympathetically maintained painstates, ischemic pain, postherpetic neuralgia, and radiation plexopathy

 

NeurolyticBlocks

Alcohol and phenol are the preferred agents forneurolytic procedures because they cause axonal degeneration within minutes andeffectively interrupt the central transmission of pain impulses. Chemicalneurolysis can result in immediate and total pain relief in selected patientswith localized or regional pain. Opioid requirements decrease sharply, andpatients on high doses of opioids will require careful tapering to avoidrespiratory

depression. Other indications for neurolysis are costopleural syndromeand sympathetically maintained pain in Pancoast’s syndrome. Unfortunately,potentially unacceptable side effects limit the utility of neurolytic blocksbut neurolytic blocks are still preferred over standard opioid analgesia tocontrol intractable abdominal, pelvic, and perineal pain. The following four criteria must be met before a nerveblock is considered appropriate: Limited lifespan of three to six months  Afavorable risk to benefit ratio (i.e., the block will not impair bladder orbowel function or cause limb paralysis) Apoor response to primary antitumor treatment, which has not been able to reducethe tumor burden A good analgesicresponse and acceptable side effects with prognostic blocks.

Advantages: The neurolytic blocks have the following advantages in home care byrelatives of patients particularly in rural area of India: 1). Neurolytic blocksprovide longer duration of pain relief. 2).Drugs and inexpensive equipmentrequired are readily available.Elaborate equipment is not mandatory. 3).Long-term indoor ward treatment is avoided, repeated visits to the urban paincenter are not required. 4). Patient can remain at homepain free even in rural areas where medical help is scarce.

 

Table 1. AUTONOMIC NERVE BLOCKS

Neurolytic Block

Site/Condition Treated

Stellate ganglion

Head   Neck or arm pain

Gasserian ganglion

Trigeminal neuralgia and facial pain

Interpleural (thoracic sympathetic chain)

Upper—head, arms

Middle—thorax, heart, lung

Lower— abdominal organs, uterus, bladder

Celiac plexus (splanchnic nerves)

Pancreatitis, Hepatobiliary Cancer pain, visceral/GIT cancer pain upto trans. Colon.

Lumbar sympathetic

Lower limb pain, retroperitoneal pain

Hypogastric plexus

Pelvic,  Perineal, urogenital pain

Sacrococcygeal ganglion (impar, Walther)

Rectal, uretheral, perineal, vaginal pain

 

Neurolytic Celiac PlexusBlocks (NCPB) And Splanchnic Nerve Blocks (SNB) are routinely performed (and are preferredover standard analgesic therapies) for patients with intractable pain frompancreatic and upper gastrointestinal cancer. NCPBs provide immediate andsubstantial pain relief in 70 to 90 percent of cases, improve the patient’squality of life, and significantly reduce opioid intake. The procedure can berepeated in three to six months if the effect of the initial block wears off. NCPBs are performed percutaneously or intraoperatively. Underradiologic guidance, 50 to 100 percent alcohol is instilled anterior to theaorta at the level of the L1 vertebral body. Injection site pain, diarrhea, andtemporary hypotension are transient adverse effects. A low complication rate isobserved, since the risk of the neurolytic agent spreading to the somaticnerves supplying the lower limbs, bladder, and bowel is minimal 

     

Superior Hypogastric Plexus Blocks(SHPB) are indicated for unrelenting pain from cancerof the pelvic viscera. This plexus lies in front of the L5 and S1 vertebrae inthe prevertebral space. A spinal needle is placed percutaneously in this spacefrom the back under radiologic guidance. Excellent analgesia is reported by 70percent of patients after a SHPB. Reductions in pain scores and opioidconsumption are reported to be significant, even in patients with advanced disease.No major complications have been reported following SHPBs, although a potentialrisk exists for the spread of neurolytic agents to the nerve fibers controllingmicturition, bowel motility, and sexual function. The SHPB block can berepeated if pain recurs. Patients who fail two consecutive attempts arecandidates for intraspinal opioid analgesia.

          

Ganglion Impar Neurolytic Blocks relieveperineal pain from cancer of the cervix, endometrium, bladder, and rectum. Theganglion is a single, midline structure ventral to the sacrococcygeal junctionand can be accessed by a midline trans-sacral approach.

Painful input from somatic and visceralstructures can produce sympathetically maintained pain (SMP) that may bevisceral or neuropathic in nature. SympatheticGanglion Neurolysis relieves SMP and improves blood flow and is usedto treat pain from radiation plexopathy, phantom pain, herpes zoster, vascular insufficiencysecondary to malignancy, and complex regional pain syndromes (reflex sympatheticdystrophy and causalgia), with little risk of motor or sensory loss or deafferentationpain.

 Thetrigeminal nerve receives sensory input from the skin of the face, anteriortwo-thirds of the tongue, and oronasal mucosa. AnestheticBlockade Or Chemical Rhizolysis of the trigeminal ganglion or its individual branchesis indicated in orofacial malignancies with intractable head and face pain.

 

Neurolytic Spinal Blockade  can produce profound segmental analgesia.Nociceptive input is interrupted by selectively destroying the dorsal roots androotlets between the spinal cord and the dorsal root ganglia. The procedure isreserved for terminally ill patients with cancer who have a short lifeexpectancy and unilateral somatic pain localized to a few adjacent dermatomes, ideallyin the trunk and distant from sphincter or limb innervation. Combined with aunilateral cordotomy, subarachnoid  phenolblocks effectively control pain in costopleural syndrome, which is causedby invasion of the pleural cavity and thoracic wall. Adverse effects include PDPH,meningitis (rarely), persistent numbness and paresthesia, loss of motorfunction due to the unintended neurolysis of ventral rootlets, and sphincterand limb weakness.

 

Trans-sphenoid Pituitary Neuroablation: Chemical Hypophysectomy

Very useful simple intervention with 70-80% success rate in diffusecancers of advanced stage with multiple bony & spinal metastasis especiallyhormone dependent cancers not responding to all other measures.                  

3) IntraspinalOpioid Therapy

continued administration of opioids intrathecally orepidurally with or without dilute concentration of local anesthetic&adjuvant drugs is an important option for patients with thoracic, abdominal or pelviccancer pain that is refractory to conventional pharmacologic management.  Advantages include profound analgesia, oftenat a much lower opioid dose without the motor, sensory, or sympathetic block. Howevercombinations of low-dose opioids given epidurally with a local anesthetic actsynergistically to produce effective analgesia while decreasing the sideeffects. Administration can be carried out using a variety of drug-deliverysystems ranging from a temporary percutaneous epidural catheter to a totallyimplanted system. The effectiveness of preimplantation procedure andreversibility of effect makes this an attractive treatment option.

                                   

 

 

Conclusion

The management of patients with cancer pain can be a challengingtask, even for physicians trained in cancer pain management Effectivelyrelieving pain in cancer patients requires a range of treatment alternatives,including neural blockade when the patient’s pain no longer responds to opioidanalgesia. The type of neural block selected is determined by the location andmechanism of the pain, the physical status of the patient, the extent of tumorspread, and the technical skill and experience of the person performing theintervention. Non-neurolytic blocks can provide safe and effective analgesiafor the less serious conditions indicated above. Neurolytic blocks, with theirpotential for complications, are reserved for select patients who areunresponsive to standard analgesic pharmacotherapy and/or are at a moreadvanced stage of disease. However, few would question that aggressiveintervention is often appropriate. Neurolytic nerve blocks offer an excellentoption for the physician in the fight to control cancer pain. Such blocks canbe easily utilized to help provide cancer pain relief in most of patients atthe utmost needed times.

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