noteslobi.blogg.se - Extracellular fluid volume excess

Lymphoedema (classically non-pitting oedema).Hypoproteinaemia - nephrotic syndrome, malnutrition, malabsorption or liver failure.Pre-eclampsia (always check urine protein if >20 weeks pregnant and unwell/oedema).Superior vena cava obstruction (distention of neck and upper limb veins, classically non-pulsatile).Constrictive pericarditis or cardiac tamponade cause raised JVP - which unlike normal JVP will INCREASE on inspiration.Other causes of raised jugular venous pressure (JVP): Poor inspiratory effort may cause basal lung crackles - resolve after a few deep breaths.Fibrosing alveolitis also causes fine inspiratory crackles (long-standing symptoms usually).Acute anaphylaxis may cause wheezing (may have swollen lips or tongue).Pulmonary embolism (classically with no added lung sounds).Bronchospasm - eg, asthma or chronic obstructive pulmonary disease (COPD).Other causes of dyspnoea (see the separate Breathlessness article): Excretion of excess sodium and water is more difficult for injured or surgical patients. Several studies have demonstrated that even healthy subjects find it difficult to excrete solutions with a high chloride content (in comparison with solutions such as Hartmann's).So-called 'normal saline' (0.9% sodium chloride) actually contains supranormal amounts of sodium chloride (154 mmol/L sodium and chloride compared with the physiological 140 mmol/L for sodium and 95 mmol/L for chloride).The National Institute for Health and Care Excellence (NICE) recommends crystalloids that contain sodium in the range 130-154 mmol/L, with a bolus of 500 ml over less than 15 minutes for patients needing rapid fluid resuscitation. There are pros and cons of crystalloid and colloid solutions.However, the body's response to sodium excess is sluggish and even normal subjects are slow to excrete an excess sodium load.įor hospitalised patients requiring fluid therapy, be aware that:.If there is sodium depletion, the renin-angiotensin-aldosterone system is activated with consequent reduction in urinary sodium.Osmoreceptors and changes in vasopressin secretion affect urinary concentration and water excretion.In normal subjects the extracellular fluid sodium concentration and osmolality are maintained by the kidneys: The recommended intake of sodium and water for normal adults is: There can be a fifth subtype, integrating all cardiorenal involvement caused by systemic diseases. Two main types have been identified - cardiorenal, and renocardiac - based on which organ is the main originator of disease. It is now recognised that there are complex interactions between heart and kidneys which affect body fluid and sodium regulation.

Excretion of excess sodium and water is more difficult for injured or surgical patients (owing to various physiological responses to injury and surgery which affect renal function and fluid balance regulation).Increased antidiuretic hormone (ADH) secretion - eg, following head injury or major surgery.

Acute kidney injury - depending on severity and whether oliguric or not.

Postoperative patients may receive inappropriately large amounts of intravenous fluid and/or sodium.

There may be insufficient training of junior doctors regarding intravenous fluid therapy.

The risk of fluid overload is higher in elderly patients and if there is cardiac or renal impairment, sepsis, major injury or major surgery.

Iatrogenic - excessive intravenous fluids, blood transfusions:.

This results in heart failure, which usually manifests as pulmonary oedema and peripheral oedema. This article refers to fluid overload that occurs when the circulating volume is excessive, ie more than the heart can effectively cope with.