Vinay Puttanniah

Intrathecal pain pump infusions for intractable cancer pain: an algorithm for dosing without a neuraxial trial.

BACKGROUND:Patients with pain from advanced cancer often have limited life expectancy. Undergoing an epidural trial for placement of an intrathecal pump in these selected patients can exhaust limited days of life. We sought to analyze historical data at our cancer center to develop an algorithm to predict initial intrathecal pump dosing based on the starting preimplant systemic opioid regimen, thus averting an epidural trial and minimizing hospital stay. METHODS:We used data pre- and postpump from 46 cancer patients receiving systemic opioids undergoing intrathecal pump placement in the last 6 years, all of whom had undergone an epidural trial before pump placement. RESULTS:By analyzing intrathecal opioid dosage on discharge (in IV morphine equivalents) to age, type of pain, cancer type, preimplant opioid dose, and preimplant pain score using multiple regression, we created an algorithm that predicts, for cancer patients, an appropriate initial dose for an intrathecal pump based on the prepump systemic opioid dose, thus avoiding an epidural trial. The predicted value does have a broad 95% prediction interval (−122.7% to 147.6%) pointing to the value of a trial when feasible. CONCLUSIONS:When an epidural trial is not feasible and an intrathecal pump is required in a cancer patient, it is possible to predict an initial dose for the intrathecal pump based on the systemic opioid usage. This minimizes delays in achieving satisfactory analgesia and discharge to home.

A Retrospective Review and Treatment Paradigm of Interventional Therapies for Patients Suffering from Intractable Thoracic Chest Wall Pain in the Oncologic Population

INTRODUCTION Tumors invading the chest wall and pleura are often incurable, and treatment is targeted toward palliation of symptoms and control of pain. When patients develop tolerance or side effects to systemic opioid therapy, interventional techniques can better optimize a patients pain. We performed a retrospective review of 146 patients from April 2004 to January 2014 who underwent diagnostic and therapeutic procedures for pain relief. Using four patients as a paradigm for neurolytic approaches to pain relief, we present a therapeutic algorithm for treating patients with intractable thoracic chest wall pain in the oncologic population. MATERIAL AND METHODS For each patient, we describe the use of intercostal/paravertebral nerve blocks and neurolysis, pulsed radiofrequency ablation (PRFA) of the thoracic nerve roots, or intrathecal pump placement to successfully treat the patients chest wall pain. Analysis of 146 patient charts is also performed to assess effectiveness of therapy. RESULTS Seventy-nine percent of patients undergoing an intercostal nerve diagnostic blockade (with local anesthetic and steroid) stated that they had improved pain relief with 22% having prolonged pain relief (average of 21.5 days). Only 32% of successful diagnostic blockade patients elected to proceed to neurolysis, with a 62% success rate. Seven patients elected to proceed to intrathecal drug delivery. DISCUSSION Intercostal nerve diagnostic blockade with local anesthetic and steroid may lead to prolonged pain relief in this population. Furthermore, depending on tumor location, we have developed a paradigm for the treatment of thoracic chest wall pain in the oncologic population.

Ultrasound-Guided Serratus Plane Block for Treatment of Postmastectomy Pain Syndromes in Breast Cancer Patients: A Case Series.

Postmastectomy pain syndrome is common after surgical treatment for breast cancer and may be challenging to manage. Currently, there are a wide variety of approaches to treat this type of pain, including medications, physical therapy, and interventional procedures. However, because of the complexity of innervation of the breast, the serratus plane block may better target the web of nerves innervating the anterior chest wall including the breast. We present a case series of 8 patients who were successfully treated with serratus plane block for pain after treatment for breast cancer. We feel that this particular application for the serratus plane block deserves further investigation, as it is relatively easy to perform and has good clinical utility for this type of pain.

Considerations for Evaluating the Use of Intrathecal Drug Delivery in the Oncologic Patient

While the majority of cancer pain patients are successfully managed with conservative medical management, some patients may suffer from intractable pain or intolerable side effects. The implantation of an intrathecal drug delivery system offers many advantages to improve both analgesia and side effect profile. Practitioners may decide to proceed toward implantation after appropriate patient selection, and, when applicable, a suitable trial for the device. Once implantation is completed, multiple medication combinations may be used to optimize the therapeutic benefit of the device. We describe a stepwise paradigm to implement an intrathecal drug delivery program in the cancer pain population.

Patient-Reported Outcomes and Opioid Use by Outpatient Cancer Patients

The Memorial Sloan Kettering Pain Registry contains patient characteristics, treatments, and outcomes for a prospective cohort of 1,534 chronic pain cancer patients who were seen at outpatient pain service clinics. Average pain intensity (Brief Pain Inventory) was reported as mild by 24.6% of patients, moderate by 41.5%, and severe by 33.9%. The patients report of average percent pain relief and health state (EuroQOL 5 dimensions) was inversely related to average pain intensity category, whereas measures of pain interference, number of worst pain locations, and physical and psychological distress were directly related to pain intensity category. Eighty-six percent of patients received an opioid at 1 or more clinic encounters. Regression analysis revealed that male sex or being younger (65 years of age or younger) was associated with a greater likelihood of an opioid ordered. Male sex nearly doubled the likelihood of a higher dose being ordered than female sex. Bivariate analysis found that patients receiving opioids reported significantly more pain relief than no-opioid patients. However, patients receiving opioids had higher pain interference scores, lower index of health state, and more physical distress than no-opioid patients Our results identify the need to consider opioid use and dosage when attempting to understand patient-reported outcomes (PROs) and factors affecting pain management. PERSPECTIVE This report describes the results of the analyses of PROs and patient-related electronic health record data collected under standard of care from cancer patients at outpatient pain management clinics of Anesthesiology and Palliative Care at the Memorial Sloan Kettering Cancer Center. Consideration of sex and age as predictors of opioid use is critical in attempting to understand PROs and their relationship to pain management.

Interventional Pain Management for Sacroiliac Tumors in the Oncologic Population: A Case Series and Paradigm Approach

Introduction Tumors invading the sacrum and/or ilium often represent incurable metastatic disease, and treatment is targeted toward palliation of symptoms and control of pain. As systemic opioid therapy is frequently inadequate and limited by side effects, a variety of interventional techniques are available to better optimize analgesia. Using six patients as a paradigm for interventional approaches to pain relief, we present a therapeutic algorithm for treating sacroiliac tumor-related pain in the oncologic population. Methods We describe the use of ultrasound-guided proximal sacroiliac joint corticosteroid injection, sacroiliac lateral branch radiofrequency ablation, percutaneous sacroplasty, and implantable neuraxial drug delivery devices to treat malignant sacroiliac pain in six patients. Pre- and postprocedure numerical rating scale (NRS) pain scores, duration of pain relief, and postprocedure pain medication requirements were studied for each patient. Results Each patient had marked improvement in their pain based on an average postprocedure NRS difference of six points. The average duration of pain relief was eight months. In all cases, opioid requirements decreased after the intervention. Discussion Depending on tumor location, burden of disease, and patient preference, patients suffering from metastatic disease to the sacrum may find benefit from use of ultrasound-guided proximal sacroiliac joint corticosteroid injection, sacroiliac lateral branch radiofrequency ablation, percutaneous sacroplasty, dorsal column stimulator leads, and/or implantable neuraxial drug delivery devices. We provide a paradigm for treatment in this patient population.

Maxillary Nerve Entrapment

The maxillary nerve, the V2 branch of the trigeminal ganglion, innervates the sensory branches of the midface. The nerve can be entrapped in the area of foramen rotundum or infraorbital foramen, as well as by anatomical change due to dental trauma, vascular anomaly, fibrous dysplasia, scar tissue, and schwannoma, causing unilateral facial pain. Proper diagnosis and injection and/or surgical treatment can lead to improvement of symptoms.

Mandibular Nerve Entrapment

The mandibular nerve (MN), the V3 branch of the trigeminal ganglion, innervates the sensory branches of the lower face. The nerve can be entrapped in the area of foramen ovale or mental foramen, as well as by anatomical changes due to mandible fracture, dental trauma, vascular anomaly, fibrous dysplasia, scar tissue, and schwannoma, causing unilateral facial pain. Proper diagnosis and injection and/or surgical treatment can lead to improvement of symptoms.