New Postoperative Device Offers Patient-Controlled Analgesia

From the American Society of Anesthesiologists

CHICAGO—A new, self-contained narcotic delivery system allows patients to control their level of analgesia for postsurgical pain without needles. The Ionsys iontophoretic transdermal system (ITS; Ortho-McNeil) uses an imperceptible electric current to transport fentanyl across the skin and into the circulatory system. Since there is no needle, indwelling catheter, or tubing, the system is less cumbersome than the traditional patient-controlled analgesia pump. The device was presented at the annual meeting of the American Society of Anesthesiologists.

Recently approved by the FDA, the system is expected to become available for in-hospital use in the next few months.

The ITS system consists of a battery, electronics, and drug reservoir contained in the small plastic housing (see Photo). It sticks to the skin and delivers 40 μg of fentanyl within 10 minutes, with a lock-out period of 10 minutes. The patient activates it by pushing twice on the recessed button. A red light and a beep indicate that the device has been activated, and the light blinks between doses to indicate the number of doses already delivered (1 blink for every 5 doses).

Since the lock-out period is 10 minutes, the patient can initiate another dose as necessary. Analgesia should be titrated to an acceptable level before the device is applied.

Unlike a fentanyl patch, which delivers a constant dose over long periods, the ITS is a quick, on-demand delivery system intended for short-term management of acute pain in adults who require postoperative opioid analgesic. It is designed to last for 24 hours or 80 doses, whichever comes first.

Two studies that were presented at the meeting evaluated postoperative patient mobility with the ITS system as well as safety data. Previous studies have shown its equivalence to a standard regimen of IV patient-controlled analgesia with morphine for postoperative acute pain management.

David Hewitt, MD, of the PriCara Unit of Ortho-McNeil, presented data from one study in which patients had undergone total hip replacement or lower abdominal or pelvic surgery. Based on an ease-of-care questionnaire completed by patients and physical therapists, the fentanyl ITS was associated with greater ease of mobility compared with morphine IV patient-controlled analgesia. The researchers concluded that since postoperative mobility facilitates rehabilitation and physical therapy after major surgery, the fentanyl ITS may be a suitable alternative to IV patient-controlled analgesia.

Harold Minkowitz, MD, of Memorial Hermann Memorial City Hospital, Houston, commented that patient satisfaction was greater with the ITS system. He presented a pooled analysis of safety data from 4 similar randomized, active-controlled trials showing the system was safe and well tolerated among adult patients, including the elderly.

Adverse effects for the ITS system were those generally associated with opioid drug use, and the incidence rate was similar to that with morphine IV patient-controlled analgesia (Table).

Eugene Viscusi, MD, director of acute pain management, Jefferson Medical College, Philadelphia, has been involved with the ITS studies. He noted that the only obvious sign of its use is a localized, slight tanning of the skin (which eventually fades).

As with all Schedule II narcotic analgesics, a black box warning about the potential for respiratory depression or abuse is included with the product information.

Several anesthesiologists at the meeting commented that access to many new drugs and analgesic modalities in their hospitals is driven by cost. The price of Ionsys is expected to be set before the system becomes available.