Intrathecal Analgesia for Chronic Refractory Pain: Current and Future Prospects.

The intrathecal drug-delivery system (IDDS) is one mode of infusing analgesic medications directly into the cerebrospinal fluid in close proximity to their site of action. This modality has been employed in patients with refractory pain either due to malignant or non-malignant causes for over 30 years. Unfortunately, and despite the number of years it has been in use, there is still a scarcity of rigorous evidence to guide its integration into clinical practice. Current best evidence is inconclusive as to the comparative effectiveness and harms of the IDDS relative to routine medical care of patients. There are far more systematic reviews than high-quality primary comparative studies of the IDDS vs. conventional pain treatment. Existing clinical practice recommendations are best viewed as expert opinion with competing interests. This article will review the existing literature for indications, contraindications, consensus statements, different technologies, and complications of the IDDS. Although approved analgesics for IDDS delivery are limited to morphine and ziconotide, many other analgesics, alone or in combination, are routinely used in this setting. This review will also focus on the pharmacology, clinical efficacy, and safety of intrathecal medications extensively used in clinical practice; including agents approved, unapproved, and under development.

Long-lasting functional disabilities in patients who recover from coma after cardiac operations.

BACKGROUND: Uncertainty regarding the long-term functional outcome of patients who awaken from coma after cardiac operations is difficult for families and physicians and may delay rehabilitation. We studied the long-term functional status of these patients to determine if duration of coma predicted outcome. METHODS: We followed 71 patients who underwent cardiac operations; recovered their ability to respond to verbal commands after coma associated with postoperative stroke, encephalopathy, and/or seizures; and were discharged from the hospital. The Glasgow Outcome Scale Extended (GOSE) was used to assess functional disability 2 to 4 years after discharge. Outcomes were classified as favorable (GOSE scores 7 and 8) and unfavorable (GOSE scores 1-6). RESULTS: Of 71 patients identified, 39 were interviewed, 15 died, 1 refused to be interviewed, and 16 were lost to follow-up. Of the 54 patients with completed GOSE evaluations, only 15 (28%) had favorable outcomes. Among patients with unfavorable outcomes, 15 (28%) died, 14 (26%) survived with moderate disabilities, and 10 (18%) had severe disabilities. Factors associated with unfavorable outcomes were increases in duration of coma (p = 0.007), time in intensive care (p = 0.006), length of hospitalization (p = 0.004), and postoperative serum creatine kinase levels (p = 0.006). Only duration of coma was an independent predictor of unfavorable outcome (odds ratio [OR], 1.25; 95% confidence interval [CI], 1.008-1.537; p = 0.042). Patients with durations of coma greater than 4 days were more likely to have unfavorable outcomes (OR, 5.1; 95% CI, 1.3-21.3; p = 0.02). CONCLUSIONS: Two thirds of comatose patients who survived to discharge after cardiac operations had unfavorable long-term functional outcomes. A longer duration of unconsciousness is a predictor of unfavorable outcome.