American Journal of Emergency Medicine 34 (2016) 115.e5–115.e6
Contents lists available at ScienceDirect
American Journal of Emergency Medicine journal homepage: www.elsevier.com/locate/ajem
Case Report
Magnetic fields and intrathecal pump malfunction☆,☆☆ Abstract Medical technology has impacted the overall life expectancy. Many conditions traditionally considered fatal are now curable. Surviving chronic diseases and aging of the population have increased the number of people with chronic pain. Many devices are also available to manage severe refractory pain. As such, implantable drug-delivery system (IDDS) is a small battery-powered, programmable pump implanted under the subcutaneous tissue of the abdomen and connected to a small catheter tunneled into the spine. Implantable drug-delivery system is used for the administration of morphine, ziconotide, baclofen, or their mixtures into the cerebrospinal fluid. Like many medical devices, IDDS has technical glitch which limits its performance under certain conditions. Implantable drug-delivery system is susceptible to magnetic field such as a magnetic resonance imaging (MRI) which can temporarily stall the rotor of the pump motor and suspend drug delivery. We encountered a patient from out of town seen at emergency department with increased pain and symptoms of opiates withdrawal after intermittent IDDS malfunction. He denied any exposure to magnetic fields or MRI. However, the pump interrogation showed multiple motor stall events in the event log. After a detailed inquiry, the most likely cause of pump malfunction appears to be frequent placement of a laptop computer on his abdomen close to the pump. The magnets in the laptop speakers may have caused the rotor of the pump motor to stall during the computer use, and frequent stall has caused symptoms of withdrawal. No other mechanical failures were found. The patient was discharged home after the symptoms resolved, and the pump was reprogrammed. A 58-year-old man with history of multiple myeloma on remission and a recently implanted IDDS for chronic back pain visited our emergency department with increased pain and symptoms of opiates withdrawal. He reported approximately 12 hours of nausea, vomiting, abdominal cramps, diarrhea, rhinorrhea, increased back pain, and fatigue. He claimed to be familiar with these symptoms because he had experienced prior opiates withdrawal. Our evaluation revealed an irritable-appearing man. He was afebrile with blood pressure of 159/92 mm Hg and heart rate of 112 beats/min. His physical examination was unremarkable for acute findings, except for dryness of oral mucosa, piloerection, and constant yawning. An IDDS was palpable at his left paraumbilical area of the abdominal and had no signs of infection or localized tenderness. His pump was not on the recall list. Basic laboratory values were within normal limits, and his symptoms improved
☆ Sources of support: There was no financial support for this manuscript. ☆☆ Conflicts of interest: The authors have no conflicts of interest to disclose.
0735-6757/© 2015 Elsevier Inc. All rights reserved.
with intravenous fluids, antiemetics, and opiate analgesics. A device interrogation revealed a record of frequent pump-motor stall. He does not recall any exposure to magnetic fields or MRI. A catheter dye study did not reveal leakage or kinks. After a more detailed history taking, it was concluded that patient's repetitive placement of laptop computer on his abdomen may have affected the function of programmable pump. Apparently, the magnetic field of the speakers had caused the pump-motor stalling. The patient was discharged home after pump reprogramming and with instructions to avoid placing his laptop computer on the abdomen. The survival of many conditions traditionally considered fatal in recent years, and the general increase in the life expectancy had contributed to the growth of the population with chronic pain. Chronic pain has reached epidemic levels; it affects more than 70 million Americans [1]. Technological development has improved the quality of life for many patients with severe and refractory chronic pain. The concept of IDDS originated in the 19th century soon after the discovery of cocaine as a local anesthetic. The use of IDDS for spinal analgesia goes back to 1973 with the discovery of opiate receptors in the spinal cord [2]. Initially, IDDS was introduced to the clinical practice for obstetric analgesia in 1979 [3]. Since then, multiple modifications and improvements have occurred. An IDDS consists of a small battery-powered, programmable pump surgically implanted under the subcutaneous tissue of the abdominal wall and connected to a catheter tunneled to spine intrathecally. Permanent IDDSs are implanted after a successful pump trial [4]. The pump is usually refilled every 1 to 3 months at pain clinics. For many years, the primary indication for the use of IDDS has been the chronic-malignant pain, but recently, its use has been expanded to include nonmalignant pain and spasticity. Complications of an IDDS placement are often associated with postsurgical complications such as infection, bleeding, neurologic injury, or spinal fluid leak [5]. Mechanical malfunction of the pump is also of a significant concern. Prolonged IDDS motor stalling results in failure to deliver the intended medications due to occlusion of the internal tubing. As a consequence, drug withdrawal symptoms can develop [6,7]. In clinical practice, magnetic fields of MRI are always of concern. Magnetic fields cause interference with the IDDS pump by temporarily binding with the internal rotor magnet causing the motor gears to stall. Presumably, the motor should resume normal function once the magnetic field is removed [8]. However, there have been few reported cases of pump malfunction after a MRI field exposure. Theoretically, permanent motor stalling can occur if the pump is oriented 90° to the z axis of a 1.5 or 3.0-T MRI scanner [8]. This could potentially demagnetize the internal pump motor magnets causing an irreversible damage to the motor. To our knowledge, no publications regarding IDDS pump malfunction induced by the magnetic field of a laptop computer were found. Although De Andres et al [9] showed no technical or medical complications in
115.e6
B. Huh, C.J. Roldan / American Journal of Emergency Medicine 34 (2016) 115.e5–115.e6
their 3-year prospective MRI exposure study, the safety of MRIs in patients with implanted pump remains unclear. Currently, some experts recommend that pumps be interrogated after each MRI [10]. For clinicians unfamiliar with IDDS, a malfunction should be suspected when the patient presents with symptoms of withdrawal specific for the medication being infused. The priority of the treatment is always cardiovascular stabilization followed by symptoms control and supplementation of the withdrawing drug. Technical support from the manufacturer is readily available. Pump interrogation and catheter dye study should be performed promptly in order to troubleshoot system failure. The chronic pain population is on the rise, and emergency physicians are increasingly exposed to this group of patients. Devices like IDDS are now commonly used technology. Hence, there is a need for non–pain-trained physicians to be educated on basic assessment and care of patients with IDDS malfunctions which can profoundly impact patient outcomes. Magnetic fields are ubiquitous in our environment which can potentially interfere with the proper function of IDDS. Billy Huh, MD, PhD Department of Pain Medicine The University of Texas MD Anderson Cancer Center, Houston, TX Carlos J. Roldan, MD Department of Pain Medicine The University of Texas MD Anderson Cancer Center, Houston, TX Department of Emergency Medicine The University of Texas Health Science Center at Houston, Houston, TX Memorial Hermann–Texas Medical Center, Houston, TX Lyndon B. Johnson General Hospital, Houston, TX The University of Texas MD Anderson Cancer Center, Houston, TX Corresponding author. Department of Pain Medicine, MD Anderson Cancer Center, 1400 Holcombe Blvd, Suite FC13.2019, Houston, TX 77030 E-mail addresses: [email protected] [email protected] http://dx.doi.org/10.1016/j.ajem.2015.04.084
References [1] Institute of Medicine Report from the Committee on Advancing Pain Research, Care, and Education: relieving pain in America, a blueprint for transforming prevention, care, education and research. The National Academies Press; 2011 [http://books. nap.edu/openbook.php?record_id=13172&page=1]. [2] Pert CB, Snyder SH. Opiate receptor: demonstration in nervous tissue. Science 1973; 179:1011–4. [3] Alper MH. Intrathecal morphine: a new method of obstetric analgesia? Anesthesiology 1979;51:378–9. [4] Loeser JD, Butler SH, Chapman CR, Turk DC, editors. Bonica's management of pain. Philadelphia: Lippincott Williams & Wilkins; 2001. [5] Knight KH, Brand FM, Mchaourab AS, Veneziano G. Implantable intrathecal pumps for chronic pain: highlights and updates. Croat Med J 2007;48:22–34. [6] Mohammed I, Hussain A. Intrathecal baclofen withdrawal syndrome—a life threatening complication of baclofen pump: a case report. BMC Clin Pharmacol 2004;4:6. [7] Hansson L, Hunyor SN, Julius S, Hoobler SW. Blood pressure crisis following withdrawal of clonidine (Catapres, Catapresan), with special reference to arterial and urinary catecholamine levels, and suggestions for acute management. Am Heart J 1973;85:605–10. [8] Medtronic. MRI Information for SynchroMed II Pump, MRI Guidelines. http:// professional.medtronic.com/2012. [9] De Andres J, Villanueva V, Palmisani S, Cerda-Olmedo G, Lopez-Alarcon MD, Monsalve V, et al. The safety of magnetic resonance imaging in patients with programmable implanted intrathecal drug delivery systems: a 3-year prospective study. Anesth Analg 2011;112:1124–9. [10] Kosturakis A, Gebhardt A. SynchroMed II intrathecal pump memory errors due to repeated magnetic resonance imaging. Pain Physician 2012;15:475–7.
Contents lists available at ScienceDirect
American Journal of Emergency Medicine journal homepage: www.elsevier.com/locate/ajem
Case Report
Magnetic fields and intrathecal pump malfunction☆,☆☆ Abstract Medical technology has impacted the overall life expectancy. Many conditions traditionally considered fatal are now curable. Surviving chronic diseases and aging of the population have increased the number of people with chronic pain. Many devices are also available to manage severe refractory pain. As such, implantable drug-delivery system (IDDS) is a small battery-powered, programmable pump implanted under the subcutaneous tissue of the abdomen and connected to a small catheter tunneled into the spine. Implantable drug-delivery system is used for the administration of morphine, ziconotide, baclofen, or their mixtures into the cerebrospinal fluid. Like many medical devices, IDDS has technical glitch which limits its performance under certain conditions. Implantable drug-delivery system is susceptible to magnetic field such as a magnetic resonance imaging (MRI) which can temporarily stall the rotor of the pump motor and suspend drug delivery. We encountered a patient from out of town seen at emergency department with increased pain and symptoms of opiates withdrawal after intermittent IDDS malfunction. He denied any exposure to magnetic fields or MRI. However, the pump interrogation showed multiple motor stall events in the event log. After a detailed inquiry, the most likely cause of pump malfunction appears to be frequent placement of a laptop computer on his abdomen close to the pump. The magnets in the laptop speakers may have caused the rotor of the pump motor to stall during the computer use, and frequent stall has caused symptoms of withdrawal. No other mechanical failures were found. The patient was discharged home after the symptoms resolved, and the pump was reprogrammed. A 58-year-old man with history of multiple myeloma on remission and a recently implanted IDDS for chronic back pain visited our emergency department with increased pain and symptoms of opiates withdrawal. He reported approximately 12 hours of nausea, vomiting, abdominal cramps, diarrhea, rhinorrhea, increased back pain, and fatigue. He claimed to be familiar with these symptoms because he had experienced prior opiates withdrawal. Our evaluation revealed an irritable-appearing man. He was afebrile with blood pressure of 159/92 mm Hg and heart rate of 112 beats/min. His physical examination was unremarkable for acute findings, except for dryness of oral mucosa, piloerection, and constant yawning. An IDDS was palpable at his left paraumbilical area of the abdominal and had no signs of infection or localized tenderness. His pump was not on the recall list. Basic laboratory values were within normal limits, and his symptoms improved
☆ Sources of support: There was no financial support for this manuscript. ☆☆ Conflicts of interest: The authors have no conflicts of interest to disclose.
0735-6757/© 2015 Elsevier Inc. All rights reserved.
with intravenous fluids, antiemetics, and opiate analgesics. A device interrogation revealed a record of frequent pump-motor stall. He does not recall any exposure to magnetic fields or MRI. A catheter dye study did not reveal leakage or kinks. After a more detailed history taking, it was concluded that patient's repetitive placement of laptop computer on his abdomen may have affected the function of programmable pump. Apparently, the magnetic field of the speakers had caused the pump-motor stalling. The patient was discharged home after pump reprogramming and with instructions to avoid placing his laptop computer on the abdomen. The survival of many conditions traditionally considered fatal in recent years, and the general increase in the life expectancy had contributed to the growth of the population with chronic pain. Chronic pain has reached epidemic levels; it affects more than 70 million Americans [1]. Technological development has improved the quality of life for many patients with severe and refractory chronic pain. The concept of IDDS originated in the 19th century soon after the discovery of cocaine as a local anesthetic. The use of IDDS for spinal analgesia goes back to 1973 with the discovery of opiate receptors in the spinal cord [2]. Initially, IDDS was introduced to the clinical practice for obstetric analgesia in 1979 [3]. Since then, multiple modifications and improvements have occurred. An IDDS consists of a small battery-powered, programmable pump surgically implanted under the subcutaneous tissue of the abdominal wall and connected to a catheter tunneled to spine intrathecally. Permanent IDDSs are implanted after a successful pump trial [4]. The pump is usually refilled every 1 to 3 months at pain clinics. For many years, the primary indication for the use of IDDS has been the chronic-malignant pain, but recently, its use has been expanded to include nonmalignant pain and spasticity. Complications of an IDDS placement are often associated with postsurgical complications such as infection, bleeding, neurologic injury, or spinal fluid leak [5]. Mechanical malfunction of the pump is also of a significant concern. Prolonged IDDS motor stalling results in failure to deliver the intended medications due to occlusion of the internal tubing. As a consequence, drug withdrawal symptoms can develop [6,7]. In clinical practice, magnetic fields of MRI are always of concern. Magnetic fields cause interference with the IDDS pump by temporarily binding with the internal rotor magnet causing the motor gears to stall. Presumably, the motor should resume normal function once the magnetic field is removed [8]. However, there have been few reported cases of pump malfunction after a MRI field exposure. Theoretically, permanent motor stalling can occur if the pump is oriented 90° to the z axis of a 1.5 or 3.0-T MRI scanner [8]. This could potentially demagnetize the internal pump motor magnets causing an irreversible damage to the motor. To our knowledge, no publications regarding IDDS pump malfunction induced by the magnetic field of a laptop computer were found. Although De Andres et al [9] showed no technical or medical complications in
115.e6
B. Huh, C.J. Roldan / American Journal of Emergency Medicine 34 (2016) 115.e5–115.e6
their 3-year prospective MRI exposure study, the safety of MRIs in patients with implanted pump remains unclear. Currently, some experts recommend that pumps be interrogated after each MRI [10]. For clinicians unfamiliar with IDDS, a malfunction should be suspected when the patient presents with symptoms of withdrawal specific for the medication being infused. The priority of the treatment is always cardiovascular stabilization followed by symptoms control and supplementation of the withdrawing drug. Technical support from the manufacturer is readily available. Pump interrogation and catheter dye study should be performed promptly in order to troubleshoot system failure. The chronic pain population is on the rise, and emergency physicians are increasingly exposed to this group of patients. Devices like IDDS are now commonly used technology. Hence, there is a need for non–pain-trained physicians to be educated on basic assessment and care of patients with IDDS malfunctions which can profoundly impact patient outcomes. Magnetic fields are ubiquitous in our environment which can potentially interfere with the proper function of IDDS. Billy Huh, MD, PhD Department of Pain Medicine The University of Texas MD Anderson Cancer Center, Houston, TX Carlos J. Roldan, MD Department of Pain Medicine The University of Texas MD Anderson Cancer Center, Houston, TX Department of Emergency Medicine The University of Texas Health Science Center at Houston, Houston, TX Memorial Hermann–Texas Medical Center, Houston, TX Lyndon B. Johnson General Hospital, Houston, TX The University of Texas MD Anderson Cancer Center, Houston, TX Corresponding author. Department of Pain Medicine, MD Anderson Cancer Center, 1400 Holcombe Blvd, Suite FC13.2019, Houston, TX 77030 E-mail addresses: [email protected] [email protected] http://dx.doi.org/10.1016/j.ajem.2015.04.084
References [1] Institute of Medicine Report from the Committee on Advancing Pain Research, Care, and Education: relieving pain in America, a blueprint for transforming prevention, care, education and research. The National Academies Press; 2011 [http://books. nap.edu/openbook.php?record_id=13172&page=1]. [2] Pert CB, Snyder SH. Opiate receptor: demonstration in nervous tissue. Science 1973; 179:1011–4. [3] Alper MH. Intrathecal morphine: a new method of obstetric analgesia? Anesthesiology 1979;51:378–9. [4] Loeser JD, Butler SH, Chapman CR, Turk DC, editors. Bonica's management of pain. Philadelphia: Lippincott Williams & Wilkins; 2001. [5] Knight KH, Brand FM, Mchaourab AS, Veneziano G. Implantable intrathecal pumps for chronic pain: highlights and updates. Croat Med J 2007;48:22–34. [6] Mohammed I, Hussain A. Intrathecal baclofen withdrawal syndrome—a life threatening complication of baclofen pump: a case report. BMC Clin Pharmacol 2004;4:6. [7] Hansson L, Hunyor SN, Julius S, Hoobler SW. Blood pressure crisis following withdrawal of clonidine (Catapres, Catapresan), with special reference to arterial and urinary catecholamine levels, and suggestions for acute management. Am Heart J 1973;85:605–10. [8] Medtronic. MRI Information for SynchroMed II Pump, MRI Guidelines. http:// professional.medtronic.com/2012. [9] De Andres J, Villanueva V, Palmisani S, Cerda-Olmedo G, Lopez-Alarcon MD, Monsalve V, et al. The safety of magnetic resonance imaging in patients with programmable implanted intrathecal drug delivery systems: a 3-year prospective study. Anesth Analg 2011;112:1124–9. [10] Kosturakis A, Gebhardt A. SynchroMed II intrathecal pump memory errors due to repeated magnetic resonance imaging. Pain Physician 2012;15:475–7.
