Background Twenty per cent of Americans die using ICU services. Efforts to improve palliative care overall must therefore involve the ICU, yet the ICU presents many difficult ethical challenges not always found in other settings.

Aim To review the ethical challenges of providing high quality palliative care in the ICU.

Methods Clinical experience and review of the literature

Results Three classical philosophical distinctions continue to resonate through end-of-life care in the ICU—the distinction between killing versus allowing-to-die, the distinction between withholding versus withdrawing treatments, and the distinction between hastening death as an intended versus merely foreseen side effect of administering analgesics and sedatives.

Discussion Using cases from my experience and the literature, each of these distinctions will be explored in terms of modern ICU care. Specifically, I will discuss the role of non-invasive mechanical ventilation, along with the withdrawal of mechanical ventilation, cardiac pacemakers, tube feedings, and oral feedings. I will discuss various approaches to providing analgesia and sedation following the withdrawal of life support, including the use of unconventional agents (eg, propofol), unconventional doses, and the debate around the use of neuromuscular blocking agents in end of life care.

Conclusion Classical philosophical dilemmas continue to generate ethical challenges to providing high quality end-of-life care in the ICU, and careful normative analysis can help to clarify the issues involved and guide practice.