Multimodal intrathecal analgesia in refractory cancer pain

Intrathecal drug delivery for cancer pain at the end of life: a case study

Two-thirds of patients with advanced cancer have pain and, of these, approximately 10-20% do not respond to conventional pain management approaches. This case study concerns a hospice patient who received intrathecal drug delivery for intractable cancer pain at the end of life. This involved working in partnership with a hospital-based interventional pain team. Despite side-effects and complications associated with intrathecal drug delivery and the requirement for inpatient nursing care, intrathecal drug delivery was the best option for the patient. The case identifies the importance of a patient-centred approach to decision-making, effective partnerships between hospice and acute hospital teams, and nurse education as key factors contributing to the provision of safe and effective intrathecal drug delivery.

Comparison of external system and implanted system in intrathecal therapy for refractory cancer pain in China: A retrospective study

INTRODUCTION

Intrathecal therapy (ITT) via an implanted system was demonstrated for the treatment of refractory cancer pain for decades. Recently, the dissemination of ITT is enhanced in an external system way in Asia for a lower implantation cost. This study compares the efficacy, safety, and cost of the two ITT systems in refractory cancer pain patients in China.

METHODS

One hundred and thirty-nine cancer pain patients who underwent implantation of the ITT system were included. One hundred and three patients received ITT via the external system (external group), while 36 patients received ITT via the implanted system (implanted group). A 1:2 propensity score matching procedure was used to yield a total of 89 patients for the final analysis. Medical records of included patients were retrospectively reviewed and pain scores, incidences of complications, and costs were compared.

RESULTS

ITT via the external system provided pain relief as potent as ITT via the implanted system but was less time-consuming in the implantation phase (13 vs. 19 days, p < .01). Nausea/vomiting and urinary retention were the most frequent adverse events in both external and implanted groups (32.14%, 16.07% vs. 36.36%, 21.21%). No significant difference was found in the incidences of all kinds of complications. Compared to the implanted group, the external group cost less for the initial implantation (7268 vs. 26,275 US dollar [USD], p < .001) but had a significant higher maintenance cost (606.62 vs. 20.23 USD calculated monthly, p < .001).

CONCLUSIONS

ITT via the external system is as effective and safe as that via the implanted system and has the advantage of being cheap in the upfront implantation but costs more during the maintenance process in China.

Management of Cancer-Related Pain With Intrathecal Drug Delivery: A Systematic Review and Meta-Analysis of Clinical Studies

BACKGROUND

Despite increased attention paid to assessment and management, pain continues to be a prevalent and undertreated symptom in patients with cancer. Intrathecal drug delivery (IDD) is a therapeutic option that allows targeted delivery of analgesics to the intrathecal space.

OBJECTIVE

The aim of this review was to examine the efficacy of managing cancer-related pain with IDD. Secondary objectives included the effects of IDD on systemic opioid use and infection rates.

EVIDENCE REVIEW

A systematic search of the literature published between 1990 and 2019 was performed to identify studies evaluating the efficacy and/or safety of IDD with external or implanted pumps in patients with cancer-related pain. Data were extracted and meta-analyses performed to determine the mean changes in pain levels at short-, mid-, and long-term intervals; changes in opioid (oral morphine equivalent [OME]) daily dose; and infection rates. Changes were assessed compared with baseline.

FINDINGS

Pain levels were decreased from baseline: On a 0 to 10 scale, mean differences were -4.34 (95% CI [-4.93 to -3.75], p < 0.001) at 4 to 5 weeks; -4.34 (95% CI [-5.07 to -3.62], p < 0.001) at 6 to 12 weeks; and -3.32 (95% CI [-4.60 to -2.04], p < 0.001) at >6 months. Weighted mean OME consumption was reduced by 308.24 (SE = 22.72) mg/d. Weighted mean infection rates were ∼3% for external and implanted pumps.

CONCLUSIONS

Meta-analyses show a statistically significant and sustained decrease in cancer pain with IDD, compared with baseline. Systemic opioid consumption was reduced on average by >50% after IDD. Infection rates were comparable with other indications.

The Options for Neuraxial Drug Administration

Neuraxial drug administration, i.e., the injection of drugs into the epidural or intrathecal space to produce anesthesia or analgesia, is a technique developed more than 120 years ago. Today, it still is widely used in daily practice in anesthesiology and in acute and chronic pain therapy. A multitude of different drugs have been introduced for neuraxial injection, only a part of which have obtained official approval for that indication. A broad understanding of the pharmacology of those agents is essential to the clinician to utilize them in a safe and efficient manner. In the present narrative review, we summarize current knowledge on neuraxial anatomy relevant to clinical practice, including pediatric anatomy. Then, we delineate the general pharmacology of neuraxial drug administration, with particular attention to specific aspects of epidural and intrathecal pharmacokinetics and pharmacodynamics. Furthermore, we describe the most common clinical indications for neuraxial drug administration, including the perioperative setting, obstetrics, and chronic pain. Then, we discuss possible neurotoxic effects of neuraxial drugs, and moreover, we detail the specific properties of the most commonly used neuraxial drugs that are relevant to clinicians who employ epidural or intrathecal drug administration, in order to ensure adequate treatment and patient safety in these techniques. Finally, we give a brief overview on new developments in neuraxial drug therapy.

Effectiveness of collaboration between oncology pharmacists and anaesthesiologists for inpatient cancer pain management: A pilot study in Taiwan

OBJECTIVE

To evaluate the effectiveness of the collaboration between oncology pharmacists and anaesthesiologists for improving pain control management in cancer patients.

METHODS

This retrospective case-control pilot study enrolled inpatients with active cancer and a pain score of >3 at least once per day for 3 consecutive days. The study group was selected from June 2018 to January 2019. Patients with the same inclusion criteria were selected between November 2017 and May 2018 to serve as the comparison group. The primary outcome was the percentage of patients that experienced pain relief within 7 days from initial pain attack.

RESULTS

A total of 71 and 77 patients were enrolled in the study and comparison groups. More patients in the study group experienced pain relief within 7 days from the index date (78.9% [56 of 71 patients] versus 72.7% [56 of 77 patients], respectively). The service increased the rate of intervention from attending physicians within 4 days from index date and quality of opioid management.

CONCLUSION

The collaboration between oncology pharmacists and anaesthesiologists for cancer pain management may be associated with an increase in the rate of pain relief in cancer patients with poor pain control.

Gabapentin enhances the antinociceptive effect of intrathecal morphine in refractory cancer pain patients

PURPOSE

Morphine infusion through Intrathecal Drug Delivery System (IDDS) is widely used to relieve refractory cancer pain. However, continuous escalation of morphine dose caused by opioid tolerance and/or progress of cancer was commonly observed. Combining morphine with medications of different analgesic mechanisms is applied to blunt the rate of morphine increase. The purpose of this study was to determine the analgesic efficacy and safety of combining gabapentin with morphine after IDDS implantation.

METHODS

This study compared patients that received IDDS implantation from January 1, 2017 to November 10, 2018 in our institute. Key outcomes included change in mean pain score, dose of morphine used in patients, percentage of patients with 30% and 50% reduction in mean pain score, Patient Global Impression of Change scores, breakthrough pain characters and side effects.

RESULTS

34 patients in the combination group (morphine + gabapentin) and 40 patients in the monotherapy group(morphine)were analyzed. The results showed that both therapy groups achieved similar analgesic efficacy, demonstrated by Numerical rating scale (2.42 ± 0.88 vs 2.57 ± 0.85; Combination vs Monotherapy), PGIC and responder status. Mean daily dose of morphine was significantly lower in combination group compared to monotherapy group (3.54 ± 1.29 mg vs 4.64 ± 1.28 mg, P = 0.007). More patients experienced dizziness and somnolence after receiving combination therapy compared to morphine-alone treatment although no statistical significance was found (P = 0.49).

CONCLUSION

Addition of gabapentin achieved similar analgesic efficacy with lower dose of morphine compared to morphine alone accompanying with higher incidence of dizziness and somnolence.

Interventional Therapies for Pain in Cancer Patients: a Narrative Review

PURPOSE OF REVIEW

Pain is a prevalent symptom in the lives of patients with cancer. In light of the ongoing opioid epidemic and increasing awareness of the potential for opioid abuse and addiction, clinicians are progressively turning to interventional therapies. This article reviews the interventional techniques available to mitigate the debilitating effects that untreated or poorly treated pain have in this population.

RECENT FINDINGS

A range of interventional therapies and technical approaches are available for the treatment of cancer-related pain. Many of the techniques described may offer effective analgesia with less systemic toxicity and dependency than first- and second-line oral and parenteral agents. Neuromodulatory techniques including dorsal root ganglion stimulation and peripheral nerve stimulation are increasingly finding roles in the management of oncologic pain. The goal of this pragmatic narrative review is to discuss interventional approaches to cancer-related pain and the potential of such therapies to improve the quality of life of cancer patients.

[Radiosurgical hypophysectomy in cancer pain treatment. Literature review and clinical case]

Cancer pain is one of the main problem in modern medicine. According European Society for Medical Oncology data, cancer pain prevalence is 64% among patient with terminal stage of disease and in 46% standard pain therapy was ineffective. Radiosurgical hypophysectomy is one of the important and perspective method in cancer pain treatment. This method could be offered patient with chronic disease. According literature review, endocrinology complications were very rare and occurred 10 months after therapy. Value of analgesic effect was 70-90%. In some trials, procedure was effective not only nociceptive, but also in neuropathic pain. More trials require for determination of indications and mechanism of action. The case of successful relief of resistant pain in patient with pancreatic cancer by means of radiosurgical hypophysectomy is described.

Intrathecal Morphine Infusion Therapy via a Percutaneous Port for Refractory Cancer Pain in China: An Efficacy, Safety and Cost Utilization Analysis

Purpose

Intrathecal morphine infusion therapy via a percutaneous port (IMITPP) has been used widely for its relatively low initial cost. However, there is scarce knowledge about IMITPP. In this study, we sought to evaluate efficacy, complications, and the interval required to achieve the cost equivalence of IMITPP in patients with refractory cancer pain in China.

Patients and Methods

A retrospective chart review was conducted on cancer patients who had received IMITPP at our hospital between April 2017 and April 2019. Data from the numeric pain rating scale and Karnofsky performance scores, and complications and costs related to IMITPP were collected from medical records. Daily analgesic costs before and after IMITPP were calculated based on the doses of opioids on admission and at discharge, respectively. The doses of systemic opioids before IMITPP were stratified into very high doses [VHD, oral morphine equivalent dose (OMED) >599 mg/day], high doses (HD, 300 mg/day ≤ OMED ≤ 599 mg/day), and regular doses (RD, OMED < 300 mg/day).

Results

Intrathecal morphine infusion therapy via a percutaneous port provided significant pain relief, but impaired activities of daily living in patients with refractory cancer pain. The commonly reported complications included nausea/vomiting and urinary retention, most of which were managed with symptomatic therapies. The median interval required to achieve cost equivalence was 11.44 months. The median intervals of VHD group and HD group were significantly shorter than that of RD group.

Conclusion

Intrathecal morphine infusion therapy via a percutaneous port provided effective cancer pain management without causing serious complications. Patients with higher doses of systemic opioids would economically benefit from IMITPP in a shorter time.

Effects of Intraperitoneal and Intrathecal Morphine Analgesia on the Expression of μ-Opioid Receptors in Bone Cancer Pain Rats

Backgrounds

This study compared analgesic effects and μ-opioid receptor expression levels during long-term intraperitoneal and intrathecal treatment in a bone cancer pain rat.

Methods

Twenty-four female Sprague-Dawley rats were injected Walker 256 tumor cells into the femur to create a bone cancer pain model. The control group was injected with saline intraperitoneally and intrathecally. The intraperitoneal group was injected with morphine intraperitoneally and saline intrathecally. The intrathecal group was injected saline intraperitoneally and morphine intrathecally. Changes in pain threshold, μ-opioid receptor expression levels in spinal cord, and tumor tissue were compared between 3 groups.

Results

The intrathecal morphine group and the intraperitoneal group showed no difference in analgesia effects (P > .05). Western blot and immunohistochemical staining of μ-opioid receptors demonstrated that its level in the intrathecal group was significantly lower than the intraperitoneal group (P < .05) and without significant difference with the control group (P > .05). The expression levels of μ-opioid receptor in the spinal cord tissue did not reveal a difference among these 3 groups (P > .05).

Conclusion

Intrathecal group and intraperitoneal group showed significant difference in μ-opioid receptor expressions although with no difference in analgesia effects. Long-term intrathecal morphine administration provided similar analgesia compared to systemic morphine.

Physicochemical and Microbiological Stability of a New Oral Clonidine Solution for Paediatric Use

Background

As many drugs are unavailable for paediatric use, hospital pharmacies are often required to develop suitable formulations themselves. Clonidine is commonly used in paediatrics (in severe hypertension, in opiate withdrawal syndrome, in tics and Gilles de la Tourette syndrome or in anaesthetic premedication) but no appropriate formulation has been drawn up. The aims of this work were to develop an oral solution of clonidine dedicated to children and to assess its physicochemical and microbiological stability.

Methods

Formulation of an oral solution of clonidine hydrochloride suitable for neonates and paediatrics was developed using the active pharmaceutical ingredient (API), with as few excipients as possible and without any complex excipient vehicle. A stability study was made according to GERPAC-SFPC guidelines. At each point in time (D0, D1, D7, D15, D29, D60 and D90), visual aspect (limpidity), pH and osmolality were established. Clonidine concentration was quantified using a stability-indicating HPLC-UV-DAD method previously developed from a forced degradation study and validated according to SFSTP Pharma. Microbiological stability was also tested according to the European Pharmacopeia monograph with the best adapted method (by comparing membrane filtration and inclusion). Solutions were stored in amber glass bottles with an oral adapter for up to 3 months in two different conditions: 5 °C +/– 3 °C and at 25 °C +/– 2 °C with 60 % residual humidity (climatic chamber).

Results

The formulated oral solution is composed of API at a concentration of 10 µg/mL and of potassium sorbate (0.3 %), citric acid, potassium citrate (pH 5 buffer) and sodium saccharine (0.025 %). Forced degradation highlighted six degradation products and the method was validated in the acceptance limits of ± 5 %. On D29, the mean percentages of the initial clonidine concentrations (+/–standard deviation) were 92.95+/–1.28 % in the solution stored at 25 °C +/– 2 °C and 97.44+/–1.21 % when stored at 5 °C +/– 3 °C. On D90, means were respectively 81.82+/–0.41 % and 93.66+/–0.71 %. The visual aspect did not change. Physical parameters remained stable during the study: pH varied from 4.94 to 5.09 and osmolality from 82 to 92 mOsm/kg in the two conditions tested here. Membrane filtration appeared to be the more sensitive method. Whatever the storage conditions,<1 micro-organism/mL was identified (only environmental) with no detected E.coli.

Conclusions

This formulation is stable for at least 3 months at 5 °C +/– 3 °C in amber glass bottles and for one month when stored at room temperature. Microbiological stability was proven in accordance with the European Pharmacopeia.

Neuraxial drug delivery for the management of cancer pain: cost, updates, and society guidelines

PURPOSE OF REVIEW

The present study discusses the utilization of neuraxial drug delivery (NDD) for the management of cancer pain, based on recent trials, reviews, and guidelines with a focus on cost analysis.

RECENT FINDINGS

Almost all recent publications suggest that more stringent research is needed to improve evidence on NDD, particularly as conflicting reports exist regarding cost effectiveness of drug delivery systems. The combination of local anesthetics and opioids, with or without clonidine, continues to be reported as beneficial with the utilization of patient controlled systems providing an advantage over continuous ones. Interestingly, the use of opioids as an adjunct to local anesthetics may not enhance analgesia but the addition of dexamethasone is useful for incident cancer-related bone pain. Ziconitide remains supported as first-line therapy in districts where it is available - United States and Europe. Although new targeted drugs are being designed for cancer pain management, none have seen human clinical trials in the last year.

SUMMARY

The ability to demonstrate cost effectiveness of NDD is variable from region to region. Less expensive externalized systems may pose a viable alternative. With the exception of dexamethasone, no new drugs have been shown to provide any benefit to conventional medications.

Spinal analgesia for severe cancer pain: A retrospective analysis of 60 patients

Background and aims

Pain is highly prevalent in advanced cancer, and in some patients refractory to conventional opioid treatment. For these patients, invasive methods of pain relief should be considered. Spinal administration of opioids has been shown to be an effective alternative in refractory cancer pain. The aim of this retrospective study was to collect information on the use of spinal analgesia for cancer pain in Helsinki University Hospital.

Methods

A retrospective patient chart study of all cancer patients with spinal analgesia, either intrathecal or epidural, in a single academic center during a five year period (n = 60).

Results

Forty-four patients were treated with intrathecal (IT) and sixteen with epidural (EP) technique. The most common indication for spinal analgesia was pain refractory to systemic analgesics. Good analgesia was achieved in 50% and 70% of the patients in the EP and IT groups, respectively. The median daily systemic opioid doses prior to spinal analgesia were 874.5 mg and 730.5 mg as oral morphine equivalents in the IT and EP groups, respectively. The systemic opioid could be discontinued or significantly reduced in 83% of the patients. Morphine was used in all IT infusions and most EP infusions, mostly combined with bupivacaine 10mg (IT) or 66mg (EP). The median starting doses of morphine were 3 mg/day (IT) and 19 mg/day (EP) and were increased during titration 27% to 3.8 mg/day (IT) and 91% to 36.2 mg/day (EP). Clonidine (median 0.015 mg/day IT and 0.15 mg/day EP) and/or ketamine were used as adjuvants. The average titration time to stable analgesia was 7–9 days. Numbness in lower limbs was reported by 24% of the IT group. On average, catheters were placed 98 and 61 days before death in IT and EP groups, respectively. No serious complications occurred. Catheter dislocation occurred in 27% of all sixty patients during follow-up. Treatment was discontinued in 10 patients because of catheter dislocation (n =7) or local infection (n = 3).

Conclusions and implications

Spinal administration of opioids is a safe and effective method of pain management in patients with severe cancer pain and can greatly reduce the need of systemic opioids. We are implementing closer collaboration with oncologists to provide spinal analgesia to more patients and earlier to reduce suffering. Catheter dislocation led to discontinuation of spinal analgesia in 17% of the patients and we are evaluating new ways to prevent catheter dislocation. The initial median spinal opioid dose was too low in both groups, and we are now using higher initial doses. A common adverse effect was numbness of the lower limbs, regardless of the relatively low doses of spinal bupivacaine. We now use lower doses and introduce the intrathecal catheter higher at L1–2 to reduce motor blockade at the level of conus.

As an initial intrathecal infusions we suggest: morphine dose calculated using an oral to intrathecal ratio of 1:100 (unless the patient is elderly or already drowsy), clonidine dose 30μg/day and bupivacaine dose 7.5 mg/day.