An intrathecal pump is a

medical device A medical device is any device intended to be used for medical purposes. Significant potential for hazards are inherent when using a device for medical purposes and thus medical devices must be proved safe and effective with reasonable assura ...

used to deliver (via an intrathecal

catheter In medicine, a catheter (/ˈkæθətər/) is a thin tubing (material), tube made from medical grade materials serving a broad range of functions. Catheters are medical devices that can be inserted in the body to treat diseases or perform a surgi ...

) medications directly into the space between the

spinal cord The spinal cord is a long, thin, tubular structure made up of nervous tissue, which extends from the medulla oblongata in the brainstem to the lumbar region of the vertebral column (backbone). The backbone encloses the central canal of the sp ...

and the protective sheath surrounding the spinal cord. Medications such as

baclofen Baclofen, sold under the brand name Lioresal among others, is a medication used to treat muscle spasticity such as from a spinal cord injury or multiple sclerosis. It may also be used for hiccups and muscle spasms near the end of life. It is ta ...

bupivacaine Bupivacaine, marketed under the brand name Marcaine among others, is a medication used to decrease feeling in a specific area. In nerve blocks, it is injected around a nerve that supplies the area, or into the spinal canal's epidural space. I ...

clonidine Clonidine, sold under the brand name Catapres among others, is an α2-adrenergic agonist medication used to treat high blood pressure, ADHD, drug withdrawal ( alcohol, opioids, or nicotine), menopausal flushing, diarrhea, spasticity, and c ...

morphine Morphine is a strong opiate that is found naturally in opium, a dark brown resin in poppies ('' Papaver somniferum''). It is mainly used as a pain medication, and is also commonly used recreationally, or to make other illicit opioids. T ...

hydromorphone Hydromorphone, also known as dihydromorphinone, and sold under the brand name Dilaudid among others, is an opioid used to treat moderate to severe pain. Typically, long-term use is only recommended for pain due to cancer. It may be used by mou ...

fentanyl Fentanyl, also spelled fentanil, is a very potent synthetic opioid used as a pain medication. Together with other drugs, fentanyl is used for anesthesia. It is also used illicitly as a recreational drug, sometimes mixed with heroin, cocain ...

ziconotide Ziconotide (SNX–111; Prialt), also called intrathecal ziconotide (ITZ) because of its administration route, is an atypical analgesic agent for the amelioration of severe and chronic pain. Derived from ''Conus magus'', a cone snail, it is the ...

may be delivered in this manner to minimize the side effects often associated with the higher doses used in oral or intravenous delivery of these drugs.

Medical uses

* Some cancer patients with opioid resistant pain or serious side effects may benefit from intrathecal pain management. * Probably, only some benign patients with opioid resistant pain or serious side effects are suitable for intrathecal treatment.

Application

People with

spastic diplegia Spastic diplegia is a form of cerebral palsy (CP) that is a chronic neuromuscular condition of hypertonia and spasticity—manifested as an especially high and constant "tightness" or "stiffness"—in the muscles of the lower extremities of the ...

or other forms of

spasticity Spasticity () is a feature of altered skeletal muscle performance with a combination of paralysis, increased tendon reflex activity, and hypertonia. It is also colloquially referred to as an unusual "tightness", stiffness, or "pull" of muscles ...

, or people in intolerable

pain Pain is a distressing feeling often caused by intense or damaging stimuli. The International Association for the Study of Pain defines pain as "an unpleasant sensory and emotional experience associated with, or resembling that associated with, ...

, who cannot tolerate side effects of the higher-dose oral medications of the same medication type, are potential candidates for that medication being administered via an intrathecal pump.

Construction

The implantable intrathecal pump consists of a metal

pump A pump is a device that moves fluids (liquids or gases), or sometimes slurries, by mechanical action, typically converted from electrical energy into hydraulic energy. Pumps can be classified into three major groups according to the method they u ...

which stores and delivers the medication, and an intrathecal catheter which delivers the medication from the pump to the intrathecal space in the spine where the medication takes effect. Two types of pumps are available: a constant rate pump delivers the medication at a constant rate, and a programmable pump delivers the medication according to a rate determined by a computer program. Also external pumps, with or without a subcutaneous port are used for intrathecal delivery. The implantable medical device requires a surgical procedure; sometimes a

surgeon In modern medicine, a surgeon is a medical professional who performs surgery. Although there are different traditions in different times and places, a modern surgeon usually is also a licensed physician or received the same medical training as ...

performs a trial intrathecal injection or implants a temporary intrathecal catheter and pump to determine if the medication works to begin with, and thus if a pump is appropriate. A permanent intrathecal pump is then implanted if the patient derives at least 50% improvement in his or her symptoms.

Maintenance

Refills

Intrathecal pumps require maintenance. Individuals who use these pumps will need to come into their physician's office to have the pump refilled. How frequently this occurs is dependent on several factors, including drug concentration and dosage, and pump size. The refill frequency can range between one and six months for baclofen pumps.

Replacement

Intrathecal pumps periodically need to be replaced. For baclofen pumps, this may be once every 5–7 years.

References

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External links

International Neuromodulation Society

North American Neuromodulation Society
Medical pumps Pain Implants (medicine)