5^th International Conference on
Palliative Care and Gerontology

Biography:

Dr. Duc Chung is the chief of hospice and palliative care at the VA Central California Health Care System in Fresno, CA and an assistant clinical professor at UCSF Fresno Hospice and Palliative Medicine Fellowship. He also served on the public policy and leadership committees with the American Academy of Hospice and Palliative Medicine (AAHPM) and currently the Chair-Elect of the Rehabilitation Interest Group of AAHPM. He enjoys resident and fellow teaching and mentorship. In his spare time, Dr. Chung enjoys singing and songwriting and often uses his compositions to heal and inspire patients during their difficult life journeys. 

 

 

Abstract:

Nausea and vomiting are common symptoms that diminish patients’ overall quality of life in hospice and palliative settings. Approximately 62% of patients endure nausea and vomiting at the end-of-life. These difficult-to-control symptoms require not only a thorough history and physical examination but a broad understanding of the pathophysiology and mechanisms of action of different medications to effectively control nausea and vomiting. Key points in our history include obtaining details about positional vertigo, abdominal pain, early satiety, headaches with early morning nausea, increased CNS tumor burden, and ruling out other causes of nausea and vomiting, including polypharmacy, metabolic derangements, and psychological factors such as anxiety. It is also important to keep in mind that any particular patient can present with nausea and vomiting of multifactorial etiologies. The pathophysiology of nausea and vomiting involve the peripheral, cortical, chemoreceptor trigger zone (CTZ), and vestibular pathways. Within these pathways are mu, dopaminergic, muscarinic, and cannabinoid receptors that signal into the vomiting center, resulting in the nausea and vomiting reflex. For example, the peripheral pathway include mechano and chemoreceptors in the GI tract, serosa, viscera and provide afferents to the vomiting center via the vagas and splanchnic nervous systems, the glossopharyngeal nerve and sympathetics. The cortical pathway involve inputs from the sensory system as well as anxiety. The chemoreceptor trigger zone, located outside of the blood brain barrier, receives afferents from toxic triggers in the bloodstream and CSF which feed into the vomiting center. Blocking these various pathways will provide symptomatic relief. Various medications such as the commonly used Zofran, Compazine, Reglan, Haldol, Phenergan act through blocking various receptors that reduce signal pathways to the vomiting center. Recent evidence also demonstrated potential utility of NK-1 receptor antagonist such as aprepitant in the management of refractory nausea and vomiting. Furthermore, numerous studies have demonstrated potential utility of cannabinoid-containing medications such as dronabinol. The overall premise of nausea and vomiting management center around targeting multiple receptors simultaneously to block signal pathways to the vomiting center, thereby providing symptomatic relief. In summary, this presentation will highlight the pertinent questions that we should address during our history taking with emphasis on the pathophysiology of nausea and vomiting, the various receptors involved, medications employed to target these receptors, and explore novel medical and alternative interventions to target nausea and vomiting. A deep understanding of nausea and vomiting pathways will significantly alleviate much of these distressing symptoms.