Prevalence of QTc Prolongation in Patients With Advanced Cancer Receiving Palliative Care-A Cause for Concern?

CONTEXT: Medications commonly used for symptom control along with other known risk factors have the potential to prolong ventricular repolarization as measured by the QT interval (the time from the start of the Q wave to the end of the T wave) on a standard electrocardiogram (ECG). OBJECTIVES: To document the prevalence of a prolonged QT interval corrected for heart rate (QTc) interval in the palliative/oncology setting, compare automatic ECG QTc measurements with manual readings and identify any correlation between QTc prolongation and the use of drugs or other risk factors. METHODS: A convenience sample of consecutive patients with cancer, admitted under or known to the palliative/supportive care teams in two metropolitan hospitals, and willing to provide an ECG recording and basic demographic information including QTc risk factors were included. Both automated and manually calculated QTc intervals were recorded. Multivariable analysis was used to determine risk factors independently associated with prolonged QTc intervals. RESULTS: Of the 389 participants, there was a significant difference in mean QTc between sites using automated but not manual calculations. Manual readings were therefore used with predetermined cutoffs of 0.44 seconds (males) and 0.46 seconds (females). Seventy-two (18.5%) of the participants had a prolonged QTc with six (1.5%) having a prolongation of >0.50 seconds. At-risk drugs were being taken by 218 participants (56.0% of total cohort). Factors shown to be associated with QTc prolongation included age, gender, performance status, and hypocalcemia. No specific medication was associated with increased risk. CONCLUSION: Although almost 20% of patients receiving palliative care had prolongation of QTc, the possibility of serious consequences appeared to be low despite the frequent occurrence of risk factors.

Regular dosing compared with as-needed dosing of opioids for management of chronic cancer pain: systematic review and meta-analysis.

Opioids are the recommended form of analgesia for patients with persistent cancer pain, and regular dosing "by the clock" is advocated in many international guidelines on cancer pain management. The development of sustained-release opioid preparations has made regular dosing easier for patients. However, patients report that the intensity and impact of their cancer pain varies considerably day to day, and many try to find a trade-off between acceptable pain control and impact of cognitive (and other) adverse effects on daily activities. In acute care settings, (eg, postoperative) as-needed dosing and other opioid-sparing approaches have resulted in better patient outcomes compared with regular dosing. The aim of this study was to determine whether regular dosing of opioids was superior to as-needed dosing for persistent cancer pain. We systematically searched for randomised controlled trials that directly compared pain outcomes from regular dosing of opioids with as-needed dosing in adult cancer patients. We identified 4347 records, 25 randomised controlled trials meet the inclusion criteria, 9 were included in the review, and 7 of these included in meta-analysis. We found no clear evidence demonstrating superiority of regular dosing of opioids compared with as-needed dosing in persistent cancer pain, and regular dosing was associated with significantly higher total opioid doses. There was, however, a paucity of trials directly answering this question, and low-quality evidence limits the conclusions that can be drawn. It is clear that further high-quality clinical trials are needed to answer this question and to guide clinical practice.

Evidence-Based Palliative Care 13 Years On: Has anything changed?

There is a paucity of data on whether interventions in individual palliative care units are evidence-based. Thirteen years ago an initial study evaluated the evidence base of interventions in palliative care. Using similar methodology in the present study, we evaluated the evidence for interventions performed in an inpatient palliative care setting, looking at level of evidence as well as quality and outcome of evidence. More than half of all the interventions (47 interventions, 59 percent) we looked at in a Brisbane, Australia, inpatient palliative care setting were based on a high level of evidence in the form of systematic reviews of randomized controlled trials (level I or level II). There were only a few interventions (10 percent) for which no evidence could be retrieved. Our results show that the evidence base for interventions in palliative care continues to evolve, but that there are still areas for which further high-quality studies are needed.

Ketamine for rapid sequence induction in patients with head injury in the emergency department.

OBJECTIVE: To examine the evidence regarding the use of ketamine for induction of anaesthesia in patients with head injury in the ED. METHOD: A literature review using the key words ketamine, head injury and intracranial pressure. RESULTS: Advice from early literature guiding against the use of ketamine in head injury has been met with widespread acceptance, as reflected by current practice. That evidence is conflicting and inconclusive in regards to the safety of using ketamine in head injury. A review of the literature to date suggests that ketamine could be a safe and useful addition to our available treatment modalities. The key to this argument rests on specific pharmacological properties of ketamine, and their effects on the cerebral haemodynamics and cellular physiology of brain tissue that has been exposed to traumatic injury. CONCLUSION: In the modern acute management of head-injured patients, ketamine might be a suitable agent for induction of anaesthesia, particularly in those patients with potential cardiovascular instability.