Orthostatic hypotension: clinical review and case study

Transient loss of consciousness (TLOC) accounts for 3% of all attendance in emergency departments within the UK. More than 90% of TLOC presentations are due to epileptic seizures, psychogenic seizures or syncope. However, in England and Wales in 2002, it was estimated that 92000 patients were incorrectly diagnosed with epilepsy, at an additional annual cost to the NHS of up to £189 million. This article will reflect on the case study of a 54-year-old female patient who presented with a possible TLOC, and had a background of long-term depression. Differential diagnoses will be discussed, but the article will focus on orthostatic hypotension. Being diagnosed with this condition is independently associated with an increased risk of all-cause mortality. Causes of orthostatic hypotension and the pathophysiology behind the condition will be discussed, highlighting the importance of obtaining an accurate clinical history. This is extremely pertinent if a patient collapses in an NHS setting and this is witnessed by nurses because they can contribute to the history of the type of collapse, to aid diagnosis and correct treatment. In addition, nurses have a valuable role to play in highlighting polypharmacy to doctors, and non-medical prescribers, as a contributing factor to orthostatic hypotension is polypharmacy. It is therefore important to accurately distinguish TLOC aetiology, not only to provide appropriate management, but to also identify patients at risk of morbidity/mortality related to underlying disease.N/

Other syndromes of orthostatic intolerance : Delayed orthostatic hypotension, postprandial hypotension, postural orthostatic tachycardia syndrome, and reflex syncope

Apart from classical orthostatic hypotension, the gravitational force may strongly contribute to other forms of orthostatic intolerance, delayed and postprandial OH, postural orthostatic tachycardia syndrome (POTS), and reflex syncope. In delayed OH, the significant blood pressure drop occurs first after 3-min period of orthostasis, whereas in postprandial OH, the symptoms appear first approximately 15-30 min after the meal. POTS is rarely seen in older adults and presents as abnormal sinus tachycardia on standing with symptoms of orthostatic intolerance, dizziness, fatigue, and cognitive impairment. Reflex syncope may manifest as orthostatic vasovagal reflex, situational syncope, or carotid sinus hypersensitivity, which becomes a clinical syndrome when associated with history of unexplained syncope and positive provocation test, carotid sinus massage. Older patients with a history of orthostatic intolerance, unexplained syncope and fall trauma, and negative result of active standing test should be further evaluated using cardiovascular autonomic tests such as head-up tilt testing, Valsalva maneuver, and carotid sinus massage