Pain management surgery involves implanting a device that delivers drugs or electrical currents to the spinal cord to control chronic and severe pain. These surgical procedures are usually done after surgery has failed to relieve pain, and when medication is not giving the patient relief. In both types of pain management surgery, a temporary device is commonly tested outside the body before the operation is done.
A morphine pump implantation consists of a battery-operated pump head placed in the abdomen just under the rib cage. A catheter connected to the pump is put just under the skin and carries the drug to the spine. Small doses of morphine are delivered to the spinal fluid through electronics in the pump. The dosage can be altered with a laptop computer after this type of pain management surgery.
The pump head must be refilled with morphine about every three months. This is accomplished via a template placed on the stomach that identifies the location of a refill port. A special needle that will not damage the pump head is used, and the port is constructed of a material that closes automatically after the refill is done.
Batteries in the pump commonly work for three to six years after pain management surgery. The patient is commonly weaned off morphine gradually to prevent sudden withdrawal symptoms when the battery needs to be replaced. Occasionally, the pump will malfunction by releasing too much morphine or stop delivering the drug. In these cases, the patient could either receive an overdose of morphine or be sent into immediate drug withdrawal.
The most common complication from a morphine pump implantation is a kink or leak in the catheter. Some patients who undergo this pain management surgery also suffer spinal headaches from leaking spinal fluid shortly after surgery, but this condition usually goes away. Another complication can occur if the pump rotates while in the abdomen, blocking access to the refill port. When this happens, another surgery is required to reposition the pump.
Spinal cord stimulation involves implanting a generating device into the stomach area with wires extending to the spinal canal. The generator sends electrical impulses to nerves that control the sensation of pain. A patient can regulate the electrical pulses several times a day as needed, but after this method of pain management surgery, the patient may feel a tingling sensation instead of pain. The effectiveness of spinal cord stimulation varies from patient to patient. Some people develop a tolerance to the electrical pulses over time and discover that pain relief is no longer possible.