title: Nutrient stimulation of mesenteric blood flow - implications for older critically ill patients.
abstract: Nutrient ingestion induces a substantial increase in mesenteric blood flow. In older persons (aged ≥ 65 years), particularly those with chronic medical conditions, the cardiovascular compensatory response may be inadequate to maintain systemic blood pressure during mesenteric blood pooling, leading to postprandial hypotension. In older ambulatory persons, postprandial hypotension is an important pathophysiological condition associated with an increased propensity for syncope, falls, coronary vascular events, stroke and death. In older critically ill patients, the administration of enteral nutrition acutely increases mesenteric blood flow, but whether this pathophysiological response is protective, or precipitates mesenteric ischaemia, is unknown. There are an increasing number of older patients surviving admission to intensive care units, who are likely to be at increased risk of postprandial hypotension, both during, and after, their stay in hospital. In this review, we describe the prevalence, impact and mechanisms of postprandial hypotension in older people and provide an overview of the impact of postprandial hypotension on feeding prescriptions in older critically ill patients. Finally, we provide evidence that postprandial hypotension is likely to be an unrecognised problem in older survivors of critical illness and discuss potential options for management.
authors.affiliation: Thu AN Nguyen, Yasmine Ali Abdelhamid, Leeanne S Chapple, Adam M Deane, Discipline of Acute Care Medicine, University of Adelaide, Adelaide 5005, Australia.
authors.forename: Thu An
authors.initials: TA
authors.lastname: Nguyen
authors.affiliation: Thu AN Nguyen, Yasmine Ali Abdelhamid, Leeanne S Chapple, Adam M Deane, Discipline of Acute Care Medicine, University of Adelaide, Adelaide 5005, Australia.
authors.forename: Yasmine Ali
authors.initials: YA
authors.lastname: Abdelhamid
authors.affiliation: Thu AN Nguyen, Yasmine Ali Abdelhamid, Leeanne S Chapple, Adam M Deane, Discipline of Acute Care Medicine, University of Adelaide, Adelaide 5005, Australia.
authors.forename: Liza K
authors.initials: LK
authors.lastname: Phillips
authors.affiliation: Thu AN Nguyen, Yasmine Ali Abdelhamid, Leeanne S Chapple, Adam M Deane, Discipline of Acute Care Medicine, University of Adelaide, Adelaide 5005, Australia.
authors.forename: Leeanne S
authors.initials: LS
authors.lastname: Chapple
authors.affiliation: Thu AN Nguyen, Yasmine Ali Abdelhamid, Leeanne S Chapple, Adam M Deane, Discipline of Acute Care Medicine, University of Adelaide, Adelaide 5005, Australia.
authors.forename: Michael
authors.initials: M
authors.lastname: Horowitz
authors.affiliation: Thu AN Nguyen, Yasmine Ali Abdelhamid, Leeanne S Chapple, Adam M Deane, Discipline of Acute Care Medicine, University of Adelaide, Adelaide 5005, Australia.
authors.forename: Karen L
authors.initials: KL
authors.lastname: Jones
authors.affiliation: Thu AN Nguyen, Yasmine Ali Abdelhamid, Leeanne S Chapple, Adam M Deane, Discipline of Acute Care Medicine, University of Adelaide, Adelaide 5005, Australia.
authors.forename: Adam M
authors.initials: AM
authors.lastname: Deane
keywords: Aged; Critical care; Enteral nutrition; Mesenteric ischaemia; Postprandial hypotension