Fluids and Electrolytes in Surgical Practice.pptx

A detailed description on fluid and electrolyte in a surgical patient

1. Fluids, Electrolytes, Acid-Base Balance ES Garba

2. Teaching Objectives Body fluids distribution The kidneys' role in electrolyte balance The body's way of compensating for acid-base imbalances Major acid-base imbalances.

3. Body Homeostasis Depend on: Fluid Electrolyte Acid-base balance Disrupting factors: Surgery Illness Injury

4. Body Fluid Composition Made up of water containing solutes . These solutes are necessary for physiologic functioning. Solutes include: ( AGE ) Electrolytes Glucose Amino acids Other nutrients .

5. Types of Body Fluids Intracellular fluid ( ICF ) Intravascular fluid ( IVF ) (plasma, is found within the blood vessels and the lymphatic system ) Interstitial fluid ( ISF ) is found in the loose tissue around cells. Extracellular fluid ( ECF ), found in the spaces between cells, includes IVF and ISF .

6. Kidneys Guts Lungs Skin

7. Three Different Types of Solutions Commonly found as : Isotonic Hypotonic Hypertonic . The body constantly strives to maintain a state of balance .

8. Fluid Movement In active transport , solutes move from an area of lower concentration to an area of higher concentration. The energy required for a solute to move against a concentration gradient comes from a substance called adenosine triphosphate (ATP). Stored in all cells , ATP supplies energy for solute movement in and out of cells.

9. Solute Movement Some solutes, such as sodium and potassium , use ATP to move in and out of cells in a form of active transport called the sodium potassium pump . Other solutes that require active transport to cross cell membranes include calcium ions, hydrogen ions, amino acids , and certain sugars . Osmosis refers to the passive movement of fluid across a membrane from an area of lower solute concentration and

10. Transporting nutrients to cells and wastes from cells Transporting hormones , enzymes , blood platelets , and red and white blood cells Facilitating cellular metabolism and proper cellular chemical functioning Acting as a solvent for electrolytes and nonelectrolytes Helping maintain normal body temperature Facilitating digestion and promoting elimination Acting as a tissue lubricant Functions of Water in the Body

11. Fluid Shift Osmolality : concentration of a solution determined by the number of dissolved particles per kilogram of water. Osmolality controls water movement and distribution in body fluid compartments Diffusion : the random movement of particles in all directions through a solution Active transport : movement of solutes across membranes; requires expenditure of energy Filtration : transfer of water and solutes through a membrane from a region of high pressure to a region of low pressure Osmosis : movement of water across a membrane from a less concentrated solution to a more concentrated solution

12. Osmolality is determined by the number of dissolved particles, mainly Na , urea and glucose per kilogram of H2O Na is the largest contributor of particles To maintain balance between ICF and ECF , the body continues to shift Na and H2O between them ICF is maintained by K+ ECF is maintained by Na+

13. Regulation of F/E balance requires a constant adjustment Fluid volume , distribution , and composition is accomplished by the Kidneys and The circulatory system These two systems are influenced by the CNS , Hormones , (ADH, Aldosterone, Renin ) The thirst center in the brain.

14. Types of Fluids Crystalloids : 0.9% saline - not “ normal “ ! 5% dextrose 0.18% saline + 0.45% dextrose Others Colloids : Blood Plasma / albumin Synthetics

15. Simple Rules of Fluid Replacement Replace blood with blood Replace plasma with colloid Resuscitate with colloid Replace ECF depletion with saline Rehydrate with dextrose

16. Regulation of Fluid Volume Kidneys: Capillary pressure forces fluid through the walls and into the tubule At this point H2O or electrolytes are then either retained or excreted The urine becomes more dilute or more concentrated based on the needs of the body

17. Antidiuretic hormone (ADH) Produced by the hypothalamus Stored in the pituitary gland Restores blood volume by increasing or decreasing excretion of water Increased osmolality or decreased blood volume stimulates the release of ADH Then the kidneys reabsorb water Also may be released by stress, pain, surgery, and some meds

18. Renin-angiotensin-aldosterone system Renin secreted in kidney Amount of renin produced depends on blood flow and amount of Na in the blood Produces angiotensin II (vasoconstrictor) Angiotensin causes peripheral vasoconstriction Angiotensin II stimulates the production of aldosterone

19. Aldosterone Secreted by the adrenal gland response to angiotensin II The adrenal gland may also be stimulated by the amount of Na and K + in the blood Causes the kidneys to retain Na and H2O Leads to increases in fluid volume and Na levels Decreases the reabsorption of K+ Maintains B/P and fluid balance

20. Aldosterone Atrial natriuretic peptide or factor (ANP) (ANF) Cardiac hormone Released in response to increased pressure in the atria (increased blood volume) Opposes the renin-angiotensin-aldosterone system Stimulates excretion of Na and H2O Suppresses renin level Decreases the release of aldosterone Decreases ADH release Reduces vascular resistance by causing vasodilation

21. Space Fluid Shifting 1st space shifting- normal distribution of fluid in both the ECF compartment and ICF compartment. 2nd space shifting- excess accumulation of interstitial fluid (edema) 3rd space shifting- fluid accumulation in areas that are normally have no or little amounts of fluids (ascites)

22. How does movement from space to space occur? Diffusion Osmosis Filtration Active transport

23. Assessment of Fluid Deficit Hypotension Weak rapid pulse Temperature decreased if hypovolemic, and increased in dehydration Weight loss Skin turgor poor in dehydration and possible edema in hypovolemic Concentrated urine and blood

24. Causes of Third-Spacing Burns Peritonitis Bowel obstruction Massive bleeding into joint or cavity Liver or renal failure Lowered plasma proteins Increased capillary permeability 24

25. Normal Saline (NS) Expands IV volume Preferred fluid for immediate response Risk for fluid overload higher Does not change ICF volume Blood products Compatible with most medications

26. Lactated Ringer’s Isotonic More similar to plasma than NS Has less NaCl Has K, Ca , PO 4 3 - , lactate (metabolized to HCO 3 - ) Expands ECF

27. Plasma Expanders Stay in vascular space and increase osmotic pressure Colloids (protein solutions) Packed RBCs Albumin Plasma

28. Electrolytes Electrolytes are substances that dissociate (break up) in water into electrically charged particles, called ions . Adequate amounts of each major electrolyte and a proper balance of electrolytes are required to maintain normal physiologic functioning .

29. Electrolytes Cations : positively charged Anions : negatively charged

30. Electrolytes Major cations include sodium , potassium , calcium , and magnesium . Major anions include chloride , bicarbonate (HCO3-), and phosphate . Normally, the electrical charges of cations balance the electrical charges of anions, keeping body fluids electrically neutral.

31. Electrolytes Blood plasma contains slightly more electrolytes than does ISF . Because ions are present in such low concentrations in body fluids, they're usually expressed in milliequivalents per liter ( mEq /L). ICF and ECF cells are permeable to different substances ; therefore, these compartments normally have different electrolyte compositions

32. Solutes Ions : Na+ , Cl-, K+, PO4--- Sugars : glucose, mannitol Large molecules (colloids): albumin, hetastarch

33. Two Types of Membranes Non-brain Capillary Endothelium Is Permeable To Everything But Colloid Therefore, Only Colloid Is Osmotically Active At Non-brain Capillary Membrane.