Wednesday, December 14, 2005
Side effects of rapid opioid titration for cancer pain
The European J of Pain has an intriguing article looking at the side effects of rapid, inpatient opioid titration, from Sebastiano Mercadante's group in Palermo. If you read the abstract there is some implication that the study helps disentangle side effects from cancer vs. those from opioid titration, but this is unfortunately not true. (Some chart reviewer, presumably in his or her own idiosyncratic way, decided which side effects were from opioids and which weren't, and--perhaps an acknowledgment of how unreliable this is--these results were only mentioned qualitatively in the discussion.) Nevertheless it's an interesting study, one of those "let's look quantitatively at something we do everyday," with some findings worthy of comment.
The authors prospectively gathered symptom data from 33 patients who were admitted to a palliative care unity for acute symptom management. These patients all had cancer, but were not in the "terminal" phase (all had Karnofsky's >50 & a life expectancy >1mo). All had rapid opioid escalations (50% a day during the escalation phase) and, on average, achieved a stable opioid dose at 40 hours. They measured a bunch of symptoms at the time of admission, at the time the patient achieved a stable opioid dose, and then 10 and 20 days later. The symptoms that clearly worsed during this were drowsiness and constipation (drowsiness did abate by 20 days but remained a little higher than baseline). Dry mouth was a touch worse at the time patients achieved stability but this abated by day 10. Weakness, confusion, appetite, and mood didn't change much at all.
Most interestingly, however, is that nausea/vomiting didn't change at all during the study. The patients received anti-emetics at the treating doc's discretion (but 9 out of 33 patients received them), so this is heartening news that it appears possible to rapidly uptitrate opioids without this dread side effect.
This article also introduced me to a new word for enema: clyster.