Intrathecal Chemical Neurolysis With Phenol

Intrathecal Chemical Neurolysis With hydroxybenzeneCANCER PAINIntrathecal neurolysis with 6% pheno(prenominal) for intractable and opiate resistant perineal suffering sensation secondary to terminal bladder quartercer .Name Dr R SrivastavaDepartment Heart of England NHS Trust, Solihull.E-mail emailprotectedAbstractBackgroundIntrathecal chemical neurolysis with Phenol is a neurodestructive technique to provide saddle anaesthesia for perineal pain, in patients unresponsive to pharmacological therapy or not ameneable to surgical treatment. Its use has been advocated in patients with terminal complaint with a short life expentancy of slight than a year. Phenols neurodestructive mechanism relies on precipitation of proteins in the nerves with myelin sheath dissolution and axonal oedema, resulting in fibrosis. Neurolysis can be induced with chemicals equal phenol or alcohol or by physical methods of radiofrquency or cryoablationNeurolytic saddl block is a high risk procedure ahe ad(p) to almost irreversible neuro-destruction with meaning(a) risks including failure, paralysis and dissoluteness.Careful patient pick and psychological valuation is mandatory and comprehensive risks and benefits discernment should be carried out before embarking on this technique. Communication with patient is vital due to the resultant perspective effects of the block.ResultsPatient was extensively evaluated for the procedure with any co-morbidities and life expectancy considered and underwent subarachnoid chemical neurolysis with hyperbaric 5% phenol leading to drastic pain embossment and significant reduction in opiate consumption.Case ReportMr JJ ,a 73 year old gentleman was referred form a hospice with complaints of severe abdominal and anal pain due to a surgic anyy inoperable bladder tumour with extensive pelvic involvement and distant metastases . He was referred to our clinic from hospice with severe opiate resistant pain.Mr JJ was diagnosed with the Transitiona l Cell Carcinoma T2a N0 MX(Pulmonary nodules) G3,TCC Bladder, eight months ago when he initially presented with back and pelvic pain. He had pulmonary metastases and bladder biopsy and cystoscopy revealed a large neoplasm on the back wall of the bladder. Mr JJ underwent a radical course of radiotherapy. Subsequently he was admitted to the hospital with rectal pain . Examination under anaesthetic revealed a large mass extending from the bladder in to the prostrate.MRI scan confirmed the tumour with invasion of seminal vesicles and of the prostrate.He underwent ureteric stenting for his right hydronephrosis and hydroureter.His background included history of chronic obstructive airway indisposition, hypertension, diabetes, Ischaemic heart disease(Coronary stenting 5 years ago) and hypothyroidism.His pain at the sentence remained unsettled with associated symptoms of tenesmus, nausea and vomiting and profound saplessness. Mr JJ lived alone and was unable to cope on his own and was referred to hospice for further palliative care.He was initially treated with Zomorph 30mg doubly a day and with Oromorph as a PRN social disease for breakthrough pain. cark worsened over a period of six weeks when it was decided to start up him on a syringe driver of diamorphine 30 mgs and metoclopramide30 mgs. Inspite of some relief, he remained extremely confused and constipated.His syringe driver was changed to alfentanil 5mgs and haloperidol 3 mgs to reduce the bewilderment and drowsiness. Subsequent increment of alfentanil dose via the syringe driver did not resolve his rectal pain.In view of his worsening symptoms and prognosis ,saddle block with phenol for rectal pain remained the only viable option.After a careful assessment and explanation of the risks ( double incontinence and possible paralysis) and benefits of the procedure explained, patient was transferred to our centre as a day case and underwent intrathecal neurolysis with phenol.1 ml of 5% phenol in glycerol was injected intrathecally and flushed with 0.2 mls of 0.5% hyperbaric bupivacaine. Patient was sat up for 30 legal proceeding to achieve a saddle block.In recovery he seemed to be pain free with no loss of motor power. Mr JJ was transferred back to the hospice the same day.During take note up it was noted that within a few days Mr JJs alfentanil infusion was stopped and he was more awake and was managing on small doses of oral morphine of up to 40 mgs a day. His tenesmus completely disappeared but he still complained of some dull aching and deep visceral pain.Case word of honorThere are more than 5000 deaths/year related to bladder cancer in the UK and it is the seventh commonest coiffe of cancer related deaths. Our patient had an extensive blossom out of his bladder tumor resulting in a combination of background visceral pain involving the rectum causing intractable tenesmusPrevalence of cancer pain in patients with incurable or advanced disease ranges from 43 -63%. More than one third of the patients complain of significant pain during the terminal stages of the disease.1Pathophysiological MechanismsThe mechanisms involving cancer pain are Gordian and can not be solely attributed to either nociceptive ,musculoskeletal , visceral or neuropathic pain .Pain presents itself as a combination of various mechanisms, which would be dependent on the characteristics of disease progression.Visceral pain as was the case with our patient has both spinal and vagal innervation with feature of dull and screen pain with poor localization.Cancer cells in combination with the stromal cells will result in release of inflammatory markers like endothelin, bradykinin , tyrosine kinase and proteases which would lead to sensitization of the nerve fibres.Tyrosine kinase seems to campaign an important role in the sensitization of the afferent nociceptors.2Growth of the tumor may cause direct compression of the nerve fibres resulting in ischemia related neuropathic pain.Cance r induced fig up pain is a result of proliferating osteoclasts which lead to bone resorption. This also leads to stimulation of TRPV1 and acid sensing channels expressed on the nerve fibres resulting in cancer associated bone pain.Periosteal sensitization of afferent fibres in an acidic melieu contributes to the persistence of cancer pain.3Assessment of cancer pain remains interlinking and is influenced by patient population, variability in assessment tool ,scoring systems and under reporting of severity of pain by patients.4Assessment of patients with cancer requires a dimensional approach in order to evaluate the physiological, psychological and social impact on life.A careful assessment of history, symptoms, signs and disease progression is crucial. Patients expectations with regards to treatment should be discussed and the impact of pain on patients functional activity should be assessed. Patients with cancer complain of background pain and exacerbation of pain (Breakthrough Pain), which business leader be related to movement or due to progression of tumor resulting in compression of underling tissues and organs . Metastases to the bone can be the uncreated cause of pain in up to 75% of the patients.Assessment of localization, severity, duration, exacerbating and relieving factors is a must.Cancer pain patients are often on high dose of opiates for their pain control, which may have a detrimental effect on their daily living due to side effects of tolerance to opiates, opioid induced hyperalgesia, leading to inadequate pain control.Management of cancer painCancer pain management in a palliative patient is challenging and requires consideration of all aspects of pain in the terminally ill.Optimum control can only be achieved if pharmacological and bio-psycho-social element of treatment are carefully reviewed.Most patients clearly are depressed and more than 75% suffer from moderate to severe pain.Surgical management is rarely appropriate in patients wi th distant metastases but may be indicated in some circumstances like internal fixation for pathological long bone fracture. Chest drainage may be inevitable for patients with mesothelioma for recurrent pleural effusion.Radiotherapy which can be localized or wide field and may be useful in patients with metastatic bone disease with proven efficacy of up to 60%. and 25% respectively.Radioisotopes like strontium are also used to treat metastatic bone disease but may not be cost hard-hitting in all healthcare systems.Chemotherapy may be helpful in some types of cancer,provided that the tumor remains chemo-sensitive. Assessing the benefits of chemotherapy with regards to prognosis and life expectancy is crucial as the side effects of chemotherapy may be more detrimental to the patient than the pain itself.hormonal therapy has been useful in prostrate and breast cancer with anti-androgen and anti-oestrogens as both types of cancer are hormone sensitive.Pelvic pain may result from the t umor invasion to organs andThe World Health Organisation (WHO) 3 step analgesic ladder of 1986 recommends a staged approach from non-opiods like paracetamol and non-steroidal anti-inflammatory drugs to weak opioids and if necessary , immobile opioids for moderate to severe pain. However, the role of adjuvants like tricyclic anti-depressants, selective serotonin reuptake inhibitors and anticonvulsants like gabapentin and pregabalin should be considered and individualized depending on the symptomatology of the patient. NMDA antagonist like ketamine may help reduce central sensitization6Heavy reliance on strong opioids can lead to troublesome side effects which should be appropriately managed with laxatives and anti-emetics. Opioid rotation should be considered for opioid induced hyperalgesia as in the case of Mr JJ where diamorphine was substituted for alfentanil infusion.Evaluation of psychological factor of perception of pain and the behavioural responses has a significant impact o n patients lifestyle. Cognitive behavioral therapy may help elicit these perception and help individuals with chronic pain ,forming coping strategies.Pain management programme is helpful for the patient in identifying all aspects of pain and are aimed at upward(a) the quality of life.Physical therapy for pain is aimed at improving functionality and reducing the physiological deconditioning.Lifestyle adjustment in terms of daily flecks ,tasks and adapting to new envoirement should be planned for facilitating any coping strategies.Intervention techniques are aimed at targeting the source of pain involving destructive and non-destructive techniques which could involve local anesthetics and steroids for nerve blocks .Continuous infusions of local anaesthetics and opioids via a catheter placed intrathecally, can be used for spinal cord changeover and pain control. Catheter is connected to a programmable pump to administer the desired dose.Nerve destructive techniques should be only co nsidered in a multidisciplinary framework . Patient selection and progonostication of the illness is paramount.It is important that the patient has a full understanding of the procedure and the benefits at the expense of the undesired consequences of such a block like incontinence or motor paralysis.Trial of local anaesthetic is desirable in most cases to predict efficacy of further neurolysis.Neurolytic blocks necessiate the need for close monitoring and evaluation of patients pain scores in order to titrate the strong opioids accordingly.Indications and contraindications to Intrathecal neurolysisAlthough there has been a decreasing trend in the use of intrathecal neurolysis future(a) advancement in the techniques of spinal blocks with infusions of local anaesthetics and opioids intrathecal neurolysis has its place in a select subset of patients in whom the pain remains refractory inspite of conventional therapiesand treatment with strong opioids .The distinct advantage with neuro lysis is of reduction in the opiate consumption and the associated side effects. Complications of subarachanoid block include bladder and bowel dysfuction along with motor weakness .5.Pain relief associated with neurolytic blocks is short lived(less than 6 months), and disease progression may lead to refractory pain .In view of our patients limited life expectancy of less than two months with pre- exsisting bowel and bladder dysfunction ,intrathecal neurolysis was the quickest and the most cost effective way to provide pain relief.Neurodestructive techniques used in clinical put on range from cryoablation, radiofrequency lesioning to chemical neurolysis with Alcohol (50-100%),Phenol (7-12%) , Hypertonic saline and glycerol.Intrathecal neurolysisIt involves the destruction of nociceptive afferent fibres ,both myelinated and unmyelinated leading to almost instant pain relief. It is effective in well localized pain. The effect of neurolysis is short lived but it involves a short perio d of hospitalization in comparision to neurosurgical procedures like cordotomy.Phenol(7-12%) causes nerve destruction by coagulating protein in both small and large fibres which leads to degeneration of the nerves within the nerve roots involving more of the posterior than anterior columns. Nerves tend to see the light faster with phenol than alcohol .Phenol is hyperbaric and when mixed with glycerol, it tends to diffuse more slowly out of the solution causing a more targeted destruction compared to alcohol. It can be mixed with water but the nerve destruction will be more extensive.Phenol compared to alcohol is not painful on injection and for this reason alcohol injections are administered with a local anaesthetic. In immersions of lower than 5%, phenol tends to exert local anaesthetic action rather than neurodestructive. Phenol when mixed with glycerol or radiopaque dye can provide a higher concentration of up to 15%.Neurolysis with phenol in comparision to alcohol is milder a nd short lived. Due to the hyberbaric nature of phenol in comparision with alcohol, the patient is positioned with the affected side down to target the dorsal roots. Phenol being highly treacly requires a wider bore spinal needle for injection. Phenol can cause skin and tissue necrosis along with neuritis if the nerve destruction is incomplete.For patients undergoing neurolysis with alcohol the targeted side is positioned up due to the hypobaric nature of the solution. Patients are initially in the lateral position followed by proning to 45 degrees to target the dorsal roots. Alcohol may cause mild burning on injection.Hypertonic saline(10-15%) for intrathecal neurolysis can provide a significant relief of more than 50% but has significant side effects. resultantManagement of cancer pain is very complex and challenging and requires considerable expertise in providing appropriate care to terminally ill patients. Significant reliance on strong opioids is not without its side effects and a multifaceted approach towards pain control is warranted. Our patient was treated with chemical neurolysis as a last resort since all other measures had failed. Although it helped in reduction of opiate requirement and drowsiness, it still remains difficult to judge the correct dosage and concentration of phenol and balance it against the duration of pain free interval with minimum side effects for the patient before leading to death.Intrathecal neurolysis is not a routine procedure and outcomes of this type of intervention are variable. The extreme complications of this procedure and availability of other techniques makes clinicians reluctant to use in their regular clinical practice. However, cancer pain treatment needs to be tailored in accordance with the patients condition and chemical neurolysis may perhaps be the only option to relieve pain in specific patients.References1M. H. J. van den Beuken-van Everdingen, J. M. de Rijke, A. G. Kessels, H. C. Schouten, M. van Kleef, and J. Patijn, Prevalence of pain in patients with cancer a systematic review of the past 40 years, Ann. Oncol. Off. J. Eur. Soc. Med. Oncol. ESMO, vol. 18, no. 9, pp. 14371449, Sep. 2007.2S. Pezet and S. B. McMahon, NEUROTROPHINS Mediators and Modulators of Pain, Annu. Rev. Neurosci., vol. 29, no. 1, pp. 507538, 2006.3Review of Cellular Mechanisms of Tumor Osteolysis. Clinical Orthopaedics and Related Research, LWW. Online. Available http//journals.lww.com/corr/Fulltext/2000/04000/Review_of_Cellular_Mechanisms_of_Tumor_Osteolysis_.13.aspx. Accessed 23-Nov-2014.4C. Shute, The Challenges of Cancer Pain Assessment and Management, Ulster Med. J., vol. 82, no. 1, pp. 4042, Jan. 2013.5A. Watanabe and M. Yamakage, Intrathecal neurolytic block in a patient with refractory cancer pain, J. Anesth., vol. 25, no. 4, pp. 603605, Aug. 2011.6Cancer Pain Management. The British Pain Society 2010