Drug-Related Hospital Visits and Admissions Associated with Laboratory or Physiologic Abnormalities-A Systematic-Review

Countless studies have demonstrated that many emergency-room visits and hospital admissions are drug-related and that a significant proportion of these drug-related visits (DRVs) are preventable. It has not been previously studied which DRVs could be prevented through enhanced monitoring of therapy. The objective of the study was to determine the incidence of DRVs attributed to laboratory or physiologic abnormalities. Three authors independently performed comprehensive searches in relevant health care databases using pre-determined search terms. Articles discussing DRV associated with poisoning, substance abuse, or studied among existing in-patient populations were excluded. Study country, year, sample, design, duration, DRV identification method, proportion of DRVs associated with laboratory or physiologic abnormalities and associated medications were extracted. The three authors independently assessed selected relevant articles according to the Strengthening the reporting of observational studies in epidemiology (STROBE) as applicable according to the studies' methodology. The initial literature search yielded a total of 1,524 articles of which 30 articles meeting inclusion criteria and reporting sufficient laboratory or physiologic data were included in the overall analysis. Half employed prospective methodologies, which included both chart review and patient interview; however, the overwhelming majority of identified studies assessed only adverse drug reactions (ADRs) as a drug-related cause for DRV. The mean (range) prevalence of DRVs found in all studies was 15.4% (0.44%-66.7%) of which an association with laboratory or physiologic abnormalities could be attributed to a mean (range) of 29.4% (4.3%-78.1%) of cases. Most laboratory-associated DRVs could be linked to immunosuppressant, antineoplastic, anticoagulant and diabetes therapy, while physiologic-associated DRVs were attributed to cardiovascular therapies and NSAIDs. Significant proportions of laboratory and physiologic abnormalities contribute to DRVs and are consistently linked to specific drugs. These therapies are potential targets for enhanced medication monitoring initiatives to proactively avert potential DRVs.The research was funded by a Qatar University student grant.Scopu

Are Compression Stockings an Effective Treatment for Orthostatic Presyncope?

Syncope, or fainting, affects approximately 6.2% of the population, and is associated with significant comorbidity. Many syncopal events occur secondary to excessive venous pooling and capillary filtration in the lower limbs when upright. As such, a common approach to the management of syncope is the use of compression stockings. However, research confirming their efficacy is lacking. We aimed to investigate the effect of graded calf compression stockings on orthostatic tolerance

Theoretical analysis of the mechanisms of a gender differentiation in the propensity for orthostatic intolerance after spaceflight

<p>Abstract</p> <p>Background</p> <p>A tendency to develop reentry orthostasis after a prolonged exposure to microgravity is a common problem among astronauts. The problem is 5 times more prevalent in female astronauts as compared to their male counterparts. The mechanisms responsible for this gender differentiation are poorly understood despite many detailed and complex investigations directed toward an analysis of the physiologic control systems involved.</p> <p>Methods</p> <p>In this study, a series of computer simulation studies using a mathematical model of cardiovascular functioning were performed to examine the proposed hypothesis that this phenomenon could be explained by basic physical forces acting through the simple common anatomic differences between men and women. In the computer simulations, the circulatory components and hydrostatic gradients of the model were allowed to adapt to the physical constraints of microgravity. After a simulated period of one month, the model was returned to the conditions of earth's gravity and the standard postflight tilt test protocol was performed while the model output depicting the typical vital signs was monitored.</p> <p>Conclusions</p> <p>The analysis demonstrated that a 15% lowering of the longitudinal center of gravity in the anatomic structure of the model was all that was necessary to prevent the physiologic compensatory mechanisms from overcoming the propensity for reentry orthostasis leading to syncope.</p

Recommendations for tilt table testing and other provocative cardiovascular autonomic tests in conditions that may cause transient loss of consciousness. Consensus statement of the European Federation of Autonomic Societies (EFAS) endorsed by the American Autonomic Society (AAS) and the European Academy of Neurology (EAN)

An expert committee was formed to reach consensus on the use of tilt table testing (TTT) in the diagnosis of disorders that may cause transient loss of consciousness (TLOC) and to outline when other provocative cardiovascular autonomic tests are needed. While TTT adds to history taking, it cannot be a substitute for it. An abnormal TTT result is most meaningful if the provoked event is recognised by patients or eyewitnesses as similar to spontaneous events. The minimum requirements to perform TTT are a tilt table, a continuous beat-to-beat blood pressure monitor, at least one ECG lead, protocols for the indications stated below and trained staff. This basic equipment lends itself to the performance of (1) additional provocation tests, such as the active standing test, carotid sinus massage and autonomic function tests; (2) additional measurements, such as video, EEG, transcranial Doppler, NIRS, end-tidal CO2 or neuro-endocrine tests; and (3) tailor-made provocation procedures in those with a specific and consistent trigger of TLOC. TTT and other provocative cardiovascular autonomic tests are indicated if the initial evaluation does not yield a definite or highly likely diagnosis, but raises a suspicion of (1) reflex syncope, (2) the three forms of orthostatic hypotension (OH), i.e. initial, classic and delayed OH, as well as delayed orthostatic blood pressure recovery, (3) postural orthostatic tachycardia syndrome or (4) psychogenic pseudosyncope. A therapeutic indication for TTT is to teach patients with reflex syncope and OH to recognise hypotensive symptoms and to perform physical counter manoeuvres

Drug-Related Visits, overall pooled mean incidence and 95% CI.

<p>Drug-Related Visits, overall pooled mean incidence and 95% CI.</p

Flow chart of the process of identifying selected articles.

<p>This figure describes the outcomes of our outlined search strategy at various stages of the systematic review. The three authors conducted structured searches in several databases, which yielded 1,524 citations. When these titles were screened, 270 duplicate articles were identified and removed. Of the remaining titles, only 425 met our main inclusion criteria: 256 were excluded as they described illicit drug use or abuse-related DRV; 187 were DRV study in ambulatory or primary care populations; 114 were DRV study in hospitalized populations; and 272 were reviews, commentaries, editorials or letters. Subsequently 381 full text articles assessed reported data in insufficient detail to ascertain if documented DRVs could be associated with laboratory or physiologic abnormality and 14 abstracts were not available in full-text English. The remaining 30 studies were included in the review.</p

Laboratory and Physiologic-Abnormality Associated DRV, overall pooled mean incidence and 95% CI.

<p>Laboratory and Physiologic-Abnormality Associated DRV, overall pooled mean incidence and 95% CI.</p