Medical Terminology for Abdominal Morphine Pump
The medical name for an abdominal morphine pump is an "intrathecal drug delivery system" (ITDDS) or "intrathecal pump," which delivers opioid analgesics directly into the intrathecal space of the spinal canal via an implantable programmable pump. 1
Specific Terminology and Components
The system consists of several key components with precise medical nomenclature:
- Intrathecal (i.t.) implantable pump: The fully implanted programmable device that is surgically placed in the abdominal wall 1
- Intrathecal catheter: The delivery catheter that runs from the pump to the intrathecal space, typically inserted at the lumbar level 1
- Alternative terms: "Implantable infusion pump," "programmable pump," or "subcutaneous pump" are also used in the literature 2, 3
Distinguishing from Related Systems
It is important to differentiate this from other spinal drug delivery methods:
- Epidural catheter systems: Deliver medication into the epidural space rather than the intrathecal space, requiring higher doses (20-40% of systemic dose vs. only 10% for intrathecal) 1
- Percutaneous or tunneled catheters: Temporary external systems that do not involve a fully implanted pump 1
- Subcutaneous reservoir (Spinalgesic): An injectable reservoir system that requires manual bolus injections rather than continuous infusion 2
Clinical Context
The intrathecal route requires dramatically lower doses compared to other routes: only 1/300th of the oral morphine dose and 1/24th of the epidural dose for equivalent analgesia 1, 4. The fully implanted systems offer significantly lower infection risk and require less maintenance than percutaneous routes, though positioning is more complex 1. These systems are indicated for patients with life expectancy greater than 6 months who have failed conservative management and demonstrated at least 50% pain reduction during a trial period 1, 4, 5.