-
Ceska a Slovenska Oftalmologie :... 2021This article provides a comprehensive view of the issue of dry eye. It emphasizes provisions of the Tear Film and Ocular Surface Society, discusses the new... (Review)
Review
This article provides a comprehensive view of the issue of dry eye. It emphasizes provisions of the Tear Film and Ocular Surface Society, discusses the new classification and definition of dry eye based on its pathophysiology, and emphasizes the correct diagnostic and therapeutic approaches, which appears in the form of algorithms. Dry eye is a multifactorial disease of the ocular surface characterized by a loss of homeostasis of the tear film, and accompanied by ocular symptoms, in which tear film instability and hyperosmolarity, ocular surface inflammation and damage, and neurosensory abnormalities play etiological roles. Dry eye disease is a dynamic and complex disease of the ocular surface and ocular adnexa with known risk factors. It is a disease with a cyclical character, in which the most important step is to find the etiological trigger, to restore homeostasis and break the vicious circle. The key elements in the diagnosis are increased osmolarity of the tear film and inflammation of the ocular surface, which are accompanied by ocular symptoms (discomfort, visual disturbance). Inflammation is not always associated with hyperemia and can be confirmed by several techniques and methods. However, in current clinical practice, there is still no "gold standard" and sufficient tests to diagnose inflammation of the ocular surface. The treatment of dry eye disease must be individualized, dynamic and optimized for each stage of the disease.
Topics: Dry Eye Syndromes; Eye; Humans; Osmolar Concentration; Tears; Vision, Ocular
PubMed: 34107689
DOI: 10.31348/2020/29 -
JPEN. Journal of Parenteral and Enteral... May 2023Drug administration through feeding tubes presents many challenges to the healthcare provider. There is little information available on medications than can be delivered... (Review)
Review
BACKGROUND
Drug administration through feeding tubes presents many challenges to the healthcare provider. There is little information available on medications than can be delivered safely when crushed and what efforts can be implemented to minimize clogging the feeding tube. Our institution requested a comprehensive examination of all oral medications for the feeding tube route.
METHODS
This report is a synopsis of the physical evaluation of 323 different oral medications for their appropriateness for feeding tube administration with distal site in either the stomach or jejunum. A worksheet was created for each medication. This document contained a review of the chemical and physical properties that would contribute to delivery of the medication. Each medication was then studied for the degree of disintegration, pH, osmolality, and potential to form clogs. For drugs that needed to be crushed, the volume of water needed to dissolve the drug, time for that process, and volume needed to rinse the tube after administration was also studied.
RESULTS
The results of this review are summarized in a table and based on a composite of the documents cited, tests conducted, and author's judgements based all the data collected. Thirty-six medications were identified as inappropriate for feeding tube administration, and an additional 46 medications were identified as inappropriate for direct jejunal administration.
CONCLUSION
The information produced by this study will enable clinicians to make informed choices in selecting, compounding, and rinsing medications through feeding tubes. Using the template provided, they will be able to evaluate a drug not studied here for potential issues in feeding tube administration.
Topics: Humans; Enteral Nutrition; Intubation, Gastrointestinal; Pharmaceutical Preparations; Osmolar Concentration; Health Personnel; Administration, Oral
PubMed: 36847617
DOI: 10.1002/jpen.2490 -
The Korean Journal of Internal Medicine May 2023Hypernatremia is an occasionally encountered electrolyte disorder, which may lead to fatal consequences under improper management. Hypernatremia is a disorder of the... (Review)
Review
Hypernatremia is an occasionally encountered electrolyte disorder, which may lead to fatal consequences under improper management. Hypernatremia is a disorder of the homeostatic status regarding body water and sodium contents. This imbalance is the basis for the diagnostic approach to hypernatremia. We summarize the eight diagnostic steps of the traditional approach and introduce new biomarkers: exclude pseudohypernatremia, confirm glucose-corrected sodium concentrations, determine the extracellular volume status, measure urine sodium levels, measure urine volume and osmolality, check ongoing urinary electrolyte free water clearance, determine arginine vasopressin/copeptin levels, and assess other electrolyte disorders. Moreover, we suggest six steps to manage hypernatremia by replacing water deficits, ongoing water losses, and insensible water losses: identify underlying causes, distinguish between acute and chronic hypernatremia, determine the amount and rate of water administration, select the type of replacement solution, adjust the treatment schedule, and consider additional therapy for diabetes insipidus. Physicians may apply some of these steps to all patients with hypernatremia, and can also adapt the regimens for specific causes or situations.
Topics: Humans; Adult; Hypernatremia; Sodium; Osmolar Concentration; Body Water; Water
PubMed: 36578134
DOI: 10.3904/kjim.2022.346 -
Advances in Therapy Nov 2019The subcutaneous administration route is widely used to administer different types of drugs given its high bioavailability and rapid onset of action. However, the... (Review)
Review
The subcutaneous administration route is widely used to administer different types of drugs given its high bioavailability and rapid onset of action. However, the sensation of pain at the injection site might reduce patient adherence. Apart from a direct effect of the drug itself, several factors can influence the sensation of pain: needle features, injection site, volume injected, injection speed, osmolality, viscosity and pH of formulation, as well as the kind of excipients employed, including buffers and preservatives. Short and thin needles, conveniently lubricated and with sharp tips, are generally used to minimize pain, although the anatomic injection site (abdomen versus thigh) also affects the sensation of pain. Large subcutaneous injection volumes are associated with pain. In this sense, the maximum volume generally accepted is around 1.5 ml, although volumes of up to 3 ml are well tolerated when injected in the abdomen. Injected volumes of up to 0.5-0.8 ml are not expected to increase substantially the pain produced by the needle insertion. Ideally, injectable products should be formulated as isotonic solutions (osmolality of about 300 mOsm/kg) and no more than 600 mOs/kg have to be used in order to prevent pain. A pH close to the physiological one is recommended to minimize pain, irritation, and tissue damage. Buffers are frequently added to parenteral formulations to optimize solubility and stability by adjusting the pH; however, their strength should be kept as low as possible to avoid pain upon injection. The data available recommend the concentration of phosphate buffer be limited to 10 mM and that the concentration of citrate buffer should be lower than 7.3 mM to avoid an increased sensation of pain. In the case of preservatives, which are required in multiple-dose preparations, m-cresol seems to be more painful than benzyl alcohol and phenol.Funding: Sandoz SA.
Topics: Humans; Injection Site Reaction; Injections, Subcutaneous; Needles; Osmolar Concentration; Pain; Patient Compliance; Pharmaceutical Preparations; Thigh
PubMed: 31587143
DOI: 10.1007/s12325-019-01101-6 -
The Ocular Surface Jul 2017The members of the Tear Film Subcommittee reviewed the role of the tear film in dry eye disease (DED). The Subcommittee reviewed biophysical and biochemical aspects of... (Review)
Review
The members of the Tear Film Subcommittee reviewed the role of the tear film in dry eye disease (DED). The Subcommittee reviewed biophysical and biochemical aspects of tears and how these change in DED. Clinically, DED is characterized by loss of tear volume, more rapid breakup of the tear film and increased evaporation of tears from the ocular surface. The tear film is composed of many substances including lipids, proteins, mucins and electrolytes. All of these contribute to the integrity of the tear film but exactly how they interact is still an area of active research. Tear film osmolarity increases in DED. Changes to other components such as proteins and mucins can be used as biomarkers for DED. The Subcommittee recommended areas for future research to advance our understanding of the tear film and how this changes with DED. The final report was written after review by all Subcommittee members and the entire TFOS DEWS II membership.
Topics: Dry Eye Syndromes; Eye; Humans; Keratoconjunctivitis Sicca; Osmolar Concentration; Tears
PubMed: 28736338
DOI: 10.1016/j.jtos.2017.03.006 -
Journal of the International Society of... Oct 2020Despite a substantial body of research, no clear best practice guidelines exist for the assessment of hydration in athletes. Body water is stored in and shifted between... (Review)
Review
BACKGROUND
Despite a substantial body of research, no clear best practice guidelines exist for the assessment of hydration in athletes. Body water is stored in and shifted between different sites throughout the body complicating hydration assessment. This review seeks to highlight the unique strengths and limitations of various hydration assessment methods described in the literature as well as providing best practice guidelines.
MAIN BODY
There is a plethora of methods that range in validity and reliability, including complicated and invasive methods (i.e. neutron activation analysis and stable isotope dilution), to moderately invasive blood, urine and salivary variables, progressing to non-invasive metrics such as tear osmolality, body mass, bioimpedance analysis, and sensation of thirst. Any single assessment of hydration status is problematic. Instead, the recommended approach is to use a combination, which have complementary strengths, which increase accuracy and validity. If methods such as salivary variables, urine colour, vital signs and sensation of thirst are utilised in isolation, great care must be taken due to their lack of sensitivity, reliability and/or accuracy. Detailed assessments such as neutron activation and stable isotope dilution analysis are highly accurate but expensive, with significant time delays due to data analysis providing little potential for immediate action. While alternative variables such as hormonal and electrolyte concentration, bioimpedance and tear osmolality require further research to determine their validity and reliability before inclusion into any test battery.
CONCLUSION
To improve best practice additional comprehensive research is required to further the scientific understanding of evaluating hydration status.
Topics: Absorptiometry, Photon; Blood Physiological Phenomena; Body Mass Index; Body Water; Dehydration; Drinking; Electric Impedance; Hematocrit; Hormones; Humans; Neutron Activation Analysis; Osmolar Concentration; Saliva; Serum; Sodium; Sports; Tears; Thirst; Urinalysis; Vital Signs
PubMed: 33126891
DOI: 10.1186/s12970-020-00381-6 -
Diabetes Care Nov 2014The hyperosmolar hyperglycemic state (HHS) is the most serious acute hyperglycemic emergency in patients with type 2 diabetes. von Frerichs and Dreschfeld described the... (Review)
Review
The hyperosmolar hyperglycemic state (HHS) is the most serious acute hyperglycemic emergency in patients with type 2 diabetes. von Frerichs and Dreschfeld described the first cases of HHS in the 1880s in patients with an "unusual diabetic coma" characterized by severe hyperglycemia and glycosuria in the absence of Kussmaul breathing, with a fruity breath odor or positive acetone test in the urine. Current diagnostic HHS criteria include a plasma glucose level >600 mg/dL and increased effective plasma osmolality >320 mOsm/kg in the absence of ketoacidosis. The incidence of HHS is estimated to be <1% of hospital admissions of patients with diabetes. The reported mortality is between 10 and 20%, which is about 10 times higher than the mortality rate in patients with diabetic ketoacidosis (DKA). Despite the severity of this condition, no prospective, randomized studies have determined best treatment strategies in patients with HHS, and its management has largely been extrapolated from studies of patients with DKA. There are many unresolved questions that need to be addressed in prospective clinical trials regarding the pathogenesis and treatment of pediatric and adult patients with HHS.
Topics: Adult; Animals; Child; Diabetes Mellitus, Type 2; Diabetic Ketoacidosis; Glycosuria; Humans; Hyperglycemic Hyperosmolar Nonketotic Coma; Incidence; Osmolar Concentration
PubMed: 25342831
DOI: 10.2337/dc14-0984 -
Journal of Applied Physiology... Apr 2017Hypohydration, or a body water deficit, is a common occurrence in athletes and recreational exercisers following the completion of an exercise session. For those who... (Review)
Review
Hypohydration, or a body water deficit, is a common occurrence in athletes and recreational exercisers following the completion of an exercise session. For those who will undertake a further exercise session that day, it is important to replace water losses to avoid beginning the next exercise session hypohydrated and the potential detrimental effects on performance that this may lead to. The aim of this review is to provide an overview of the research related to factors that may affect postexercise rehydration. Research in this area has focused on the volume of fluid to be ingested, the rate of fluid ingestion, and fluid composition. Volume replacement during recovery should exceed that lost during exercise to allow for ongoing water loss; however, ingestion of large volumes of plain water results in a prompt diuresis, effectively preventing longer-term maintenance of water balance. Addition of sodium to a rehydration solution is beneficial for maintenance of fluid balance due to its effect on extracellular fluid osmolality and volume. The addition of macronutrients such as carbohydrate and protein can promote maintenance of hydration by influencing absorption and distribution of ingested water, which in turn effects extracellular fluid osmolality and volume. Alcohol is commonly consumed in the postexercise period and may influence postexercise rehydration, as will the coingestion of food. Future research in this area should focus on providing information related to optimal rates of fluid ingestion, advisable solutions to ingest during different duration recovery periods, and confirmation of mechanistic explanations for the observations outlined.
Topics: Dehydration; Drinking; Exercise; Fluid Therapy; Humans; Osmolar Concentration; Rehydration Solutions; Water; Water-Electrolyte Balance
PubMed: 28126906
DOI: 10.1152/japplphysiol.00745.2016 -
Sports Medicine (Auckland, N.Z.) Feb 2022Body-fluid loss during prolonged continuous exercise can impair cardiovascular function, harming performance. Delta percent plasma volume (dPV) represents the change in... (Meta-Analysis)
Meta-Analysis
The Hydrating Effects of Hypertonic, Isotonic and Hypotonic Sports Drinks and Waters on Central Hydration During Continuous Exercise: A Systematic Meta-Analysis and Perspective.
BACKGROUND
Body-fluid loss during prolonged continuous exercise can impair cardiovascular function, harming performance. Delta percent plasma volume (dPV) represents the change in central and circulatory body-water volume and therefore hydration during exercise; however, the effect of carbohydrate-electrolyte drinks and water on the dPV response is unclear.
OBJECTIVE
To determine by meta-analysis the effects of ingested hypertonic (> 300 mOsmol kg), isotonic (275-300 mOsmol kg) and hypotonic (< 275 mOsmol kg) drinks containing carbohydrate and electrolyte ([Na] < 50 mmol L), and non-carbohydrate drinks/water (< 40 mOsmol kg) on dPV during continuous exercise.
METHODS
A systematic review produced 28 qualifying studies and 68 drink treatment effects. Random-effects meta-analyses with repeated measures provided estimates of effects and probability of superiority (p) during 0-180 min of exercise, adjusted for drink osmolality, ingestion rate, metabolic rate and a weakly informative Bayesian prior.
RESULTS
Mean drink effects on dPV were: hypertonic - 7.4% [90% compatibility limits (CL) - 8.5, - 6.3], isotonic - 8.7% (90% CL - 10.1, - 7.4), hypotonic - 6.3% (90% CL - 7.4, - 5.3) and water - 7.5% (90% CL - 8.5, - 6.4). Posterior contrast estimates relative to the smallest important effect (dPV = 0.75%) were: hypertonic-isotonic 1.2% (90% CL - 0.1, 2.6; p = 0.74), hypotonic-isotonic 2.3% (90% CL 1.1, 3.5; p = 0.984), water-isotonic 1.3% (90% CL 0.0, 2.5; p = 0.76), hypotonic-hypertonic 1.1% (90% CL 0.1, 2.1; p = 0.71), hypertonic-water 0.1% (90% CL - 0.8, 1.0; p = 0.12) and hypotonic-water 1.1% (90% CL 0.1, 2.0; p = 0.72). Thus, hypotonic drinks were very likely superior to isotonic and likely superior to hypertonic and water. Metabolic rate, ingestion rate, carbohydrate characteristics and electrolyte concentration were generally substantial modifiers of dPV.
CONCLUSION
Hypotonic carbohydrate-electrolyte drinks ingested continuously during exercise provide the greatest benefit to hydration.
Topics: Bayes Theorem; Dehydration; Exercise; Humans; Osmolar Concentration; Sodium; Water-Electrolyte Balance
PubMed: 34716905
DOI: 10.1007/s40279-021-01558-y -
Annals of Medicine 2019Dehydration appears prevalent, costly and associated with adverse outcomes. We sought to generate consensus on such key issues and elucidate need for further scientific...
Dehydration appears prevalent, costly and associated with adverse outcomes. We sought to generate consensus on such key issues and elucidate need for further scientific enquiry. A modified Delphi process combined expert opinion and evidence appraisal. Twelve relevant experts addressed dehydration's definition, objective markers and impact on physiology and outcome. Fifteen consensus statements and seven research recommendations were generated. Key findings, evidenced in detail, were that there is no universally accepted definition for dehydration; hydration assessment is complex and requires combining physiological and laboratory variables; "dehydration" and "hypovolaemia" are incorrectly used interchangeably; abnormal hydration status includes and/or abnormalities in body water and serum/plasma osmolality (pOsm); raised pOsm usually indicates dehydration; direct measurement of pOsm is the gold standard for determining dehydration; pOsm >300 and ≤280 mOsm/kg classifies a person as hyper or hypo-osmolar; outside extremes, signs of adult dehydration are subtle and unreliable; dehydration is common in hospitals and care homes and associated with poorer outcomes. Dehydration poses risk to public health. Dehydration is under-recognized and poorly managed in hospital and community-based care. Further research is required to improve assessment and management of dehydration and the authors have made recommendations to focus academic endeavours. Key messages Dehydration assessment is a major clinical challenge due to a complex, varying pathophysiology, non-specific clinical presentations and the lack of international consensus on definition and diagnosis. Plasma osmolality represents a valuable, objective surrogate marker of hypertonic dehydration which is underutilized in clinical practice. Dehydration is prevalent within the healthcare setting and in the community, and appears associated with increased morbidity and mortality.
Topics: Acute Kidney Injury; Adult; Aged; Aged, 80 and over; Biomarkers; Body Fluid Compartments; Body Water; Consensus; Critical Illness; Dehydration; Delirium; Heart Failure; Humans; Inpatients; Middle Aged; Nursing Homes; Organism Hydration Status; Osmolar Concentration; Osmotic Pressure; Prevalence; Prognosis; Risk Assessment; Thromboembolism; Water-Electrolyte Balance
PubMed: 31204514
DOI: 10.1080/07853890.2019.1628352