Systematic review and narrative summary: treatments for and risk factors associated with respiratory tract secretions (death rattle) in the dying adult

Aim
To identify effective treatments and risk factors associated with death rattle in adults at the end of life.

Background
The presence of noisy, pooled respiratory tract secretions is among the most common symptoms in dying patients around the world. It is unknown if ‘death rattle’ distresses patients, but it can distress relatives and clinicians. Treatments appear unsatisfactory, so prophylaxis would be ideal if possible.

Design
Quantitative systematic review and narrative summary following Cochrane Collaboration guidelines.

Data sources
CINAHL, MEDLINE, Health Source Nursing and Web of Science were searched for international literature in any language published from 1993 - 2016 using MeSH headings and iterative interchangeable terms for ‘death rattle’.

Review Methods
Randomised controlled trials were appraised using the Cochrane Collaboration’s tool for assessing risk of bias. Non-randomised studies were assessed using ROBINS-I tool for assessing risk of bias in non-randomised studies of interventions. Instances of treatment and risk were extracted and relevant key findings extracted in line with Cochrane methods.

Results
Five randomised trials and 23 non-randomised studies were analysed. No pharmacological or non-pharmacological treatment was found superior to placebo. There was a weak association between lung or brain metastases and presence of death rattle, but otherwise inconsistent empirical support for a range of potential risk factors.

Conclusions
Clinicians have no clear evidence to follow in either treating death rattle or preventing it occurring. However, several risk factors look promising candidates for prospective analysis, so this review concludes with clear recommendations for further research.