Ketamine: does it have a role in palliative sedation?

Characterisation of palliative sedation use in inpatients at a medium-stay palliative care unit

Background

Palliative sedation has been used to refer to the practice of providing symptom control through the administration of sedative drugs. The objective of this article was to characterise palliative sedation use in inpatients at a medium-stay palliative care unit.

Material and methods

A cross-sectional study was conducted on 125 randomly selected patients (aged 15 or older) who had died in 2014. The Palliative Performance Scale was used to evaluate the functional status.

Results

Palliative sedation was documented in 34.4% of the patients and midazolam was the most commonly used sedative agent (86.0%). More than half (53.5%) of those who recieved sedation presented with delirium. Liver dysfunction was more frequent in the sedated patients (p=0.033) and patients with heart disease were less likely (p=0.026) to be sedated.

Conclusion

Palliative sedation is an ethically accepted practice. It was commonly midazolam-induced, and differences were documented, among sedated and non-sedated patients, in terms of liver dysfunction and heart disease.

Palliative Sedation for the Terminally Ill Patient

Palliative sedation (PS) is performed in the terminally ill patient to manage one or more refractory symptoms. Proportional PS, which means that drugs can be titrated to the minimum effective dose, is the form most widely used. From a quarter to a third of all terminally ill patients undergo PS, with a quarter of these requiring continuous deep sedation. The prevalence of PS varies according to the care setting and case mix. The most frequent refractory physical symptoms are delirium and dyspnea, but PS is also considered for existential suffering or psychological distress, which is an extremely difficult and delicate issue to deal with. Active consensus from the patient and advanced care planning is recommended for PS. The decision-making process concerning the continuation or withdrawal of other treatments is not the same as that used for PS. The practice differs totally from euthanasia in its intentions, procedures, and results. The most widely used drugs are midazolam and haloperidol for refractory delirium, but chlorpromazine and other neuroleptics are also effective. In conclusion, some patients experience refractory symptoms during the last hours or days of life and PS is a medical intervention aimed at managing this unbearable suffering. It does not have a detrimental effect on survival.

Palliative sedation in Germany: factors and treatment practices associated with different sedation rate estimates in palliative and hospice care services

Background

Clinical practice of Palliative Sedation (PS) varies between institutions worldwide and sometimes includes problematic practices. Little available research points at different definitions and frameworks which may contribute to uncertainty of healthcare professionals in the application of PS. This analysis investigates what demographic factors and characteristics of treatment practices differ between institutions with high versus low sedation rates estimates in Palliative and Hospice Care in Germany.

Methods

Data sets from 221 organisations from a prior online survey were separated into two sub-groups divided by their estimated sedation rate A) lower/equal to 16% (n = 187; 90.8%) and B) higher than 16% (n = 19; 9.2%) for secondary analysis. Demographic factors and characteristics of PS treatment practices between the two groups were compared using T-Tests and Chi²/ Fisher Exact Tests and considered significant (*) at two-sided p < .05.

Results

Organisations in group B report that they discuss PS for a higher proportion of patients (38.5%/10.2%, p < 0.000**), rate agitation more often as an indications for PS (78.9%/ 53.5%, p = 0.050*), and are more likely to use Lorazepam (63.2%/ 37.4%, p = 0.047*), Promethazin (26.3%/ 9.6%, p = 0.044*), and (Es-)Ketamin (31.6%/ 12.8%, p = 0.039*) than representatives in group A. Both groups differ significantly in their allocation of three case scenarios to different types of PS.

Conclusions

Both definitions and patterns of clinical practice between palliative and hospice care representatives show divergence, which may be influenced one by another. A comprehensive framework considering conceptual, clinical, ethical, and legal aspects of different definitions of PS could help to better distinguish between different types and nuances of PS.

The role of ketamine in the treatment of chronic cancer pain

Background and aim

Ketamine is a drug used for the induction and maintenance of general anesthesia, for the treatment of postoperative and posttraumatic acute pain, and more recently, for the reduction of postoperative opioid requirements. The main mechanism of action of ketamine is the antagonization of N-methyl-D-aspartate (NMDA) receptors that are associated with central sensitization. In the pathogenesis of chronic pain and particularly in neuropathic pain, an important role is played by the activation of NMDA receptors. Although ketamine is indicated and used for the treatment of chronic cancer pain as an adjuvant to opioids, there are few clinical studies that clearly demonstrate the effectiveness of ketamine in this type of pain.

The aim of this study is to analyze evidence-based clinical data on the effectiveness and safety of ketamine administration in the treatment of chronic neoplastic pain, and to summarize the evidence-based recommendations for the use of ketamine in the treatment of chronic cancer pain.

Method

We reviewed the literature from the electronic databases of MEDLINE, COCHRANE, PUBMED, MEDSCAPE (1998–2014), as well as chapters of specialized books (palliative care, pain management, anesthesia).

Results

A number of studies support the effectiveness of ketamine in the treatment of chronic cancer pain, one study does not evidence clear clinical benefits for the use of ketamine, and some studies included too few patients to be conclusive.

Conclusions

Ketamine represents an option for neoplasic pain that no longer responds to conventional opioid treatment, but this drug should be used with caution, and the development of potential side effects should be carefully monitored.