Downloaded 132 times
Uploaded byEmmanuel MANIRABONA
FLUIDS&ELECTROLYTES
Fluids and electrolyte management is important for surgical patients, as changes can occur pre, intra, and postoperatively. The document discusses fluid compartments and disorders, including volume deficits, excesses, and electrolyte abnormalities like hyponatremia, hypernatremia, hypokalemia, hyperkalemia, hypercalcemia, and hypocalcemia. Management involves assessing the patient's volume status and replacing deficits while monitoring electrolytes to prevent complications and maintain normal balance.
More Related Content
Similar to FLUIDS&ELECTROLYTES
FLUIDS&ELECTROLYTES
- 1. Fluids and Electrolytes Managementin Surgical Patient MANIRABONA Emmanuel, MD, PG-Y2, General Surgery 1
- 2. SCOPE Introduction Fluidcompartments and composition Disorders of fluid balance and management Disorders of electrolytes and management Disorders of acid base balance and management MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 2
- 3. Introduction Fluids andelectrolyte management is paramount to the surgical patient. Many changes in fluid volume and electrolyte composition can occur: • Preoperatively • Intraoperatively • Postoperatively • In response to trauma and sepsis MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 3
- 4. Body fluids TOTAL BODYWATER (TBW) • 50-60% of total body weight • Reflection of body fat • Skeletal muscles and solid organs >>> more water than bone and fat • Young lean male: 60% • Lean female: 50% • Infant: 80% MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 4
- 5. Fluid Compartments Total bodywater 3 Functional fluid compartments: PLASMA ECF INTERSTITIAL FLUID INTRACELLULAR FLUID (ICF) MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 5
- 6. Composition of fluidcompartments ECF : Na+ is the principal cation, and chloride and bicarbonate are principal anions ICF: principal cations is K+ and Mg2+, and anions are Phosphate and sulfate and proteins MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 6
- 7. Concentration gradientis maintained by Na- K ATPase in cell membranes Water is freely movable between compartments Na+ in ECF remains associated with water MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 7
- 8. Serum Osmolality Principaldeterminants of osmolality are : Na+, glucose and urea (BUN) Calculated serum osmolality = 2Na + glucose/18 + BUN/2.8 Normal ECF and ICF osmolality : 290 -310 mOsm/kg Any change in osmotic pressure: redistribution of water Isotonic change in volume : no net movement of water as long as the ionic concentration is the same MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 8
- 9. Normal exchange offluids MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 9
- 10. Disorders of bodyfluids 3 general categories o Disturbance in volume o Disturbance in concentration o Disturbance in composition MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 10
- 11. Extracellular volume fluiddeficit Most common disorder in surgical patients: Acute or chronic Acute : CVS and CNS signs Chronic Tissue signs • Decrease in skin turgor • Sunken eyes • +CVS and CNS sings MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 11
- 12. Volume Disturbance Labs Increasein BUN Hemoconcentration : Hb+++ Increase in urine osmolality Urine Na < 20 mEq/L MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 12
- 13. Causes of volumedeficit in surgery Loss of GI fluids • NG tube suctioning • Vomiting and Diarrhea • Enterocutaneous fistula Sequestration • Soft tissue injuries and Burns • Intraabdominal process (peritonitis, obstruction, prolonged surgery) MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 13
- 14. ECF excess Iatrogenic 2nd to renal dysfunction CHF Cirrhosis Elderly and cardiac patients: very susceptible to fluid excess MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 14
- 15. FLUID THERAPY Fluidtherapy in surgical patients is adjusted to each patients needs and volume status Assessing intravascular volume status is pivotal and sometimes difficult. It is based on each patient’s: Volume status (hypervolemic, normovolemic and hypovolemic) MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 15
- 16. IVF Crystalloids LactatedRinger’s and NS 0.9% are isotonic to plasma Ideal for correcting ECF volume deficits Replacement use 3: 1 rule MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 16
- 17. IVF Colloids Highmolecular weight Confined to the intravascular space Albumin, dextran, hetastarch and gelatins Replacement uses the 1:1 rule MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 17
- 18. Fluid management The principleis to replace: 1. Fluid deficit 2. Maintenance fluids 3. Ongoing losses MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 18
- 19. Preoperative fluid therapy Maintenance IV fluids For patients who are NPO before surgery 5% dextrose in 0.45% NS (K can be added in normal renal function ) 4-2-1 rule MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 19
- 20. Fluids requirement duringsurgery Calculated per hour during OR: Fluid deficit (NPO for 6+ hours): 4/2/1 Ongoing fluid requirements: 4/2/1 Replacement of blood loss Crystalloid 3:1, Colloid 1:1 “Third-space” loss uses 4/6/8 rule: • 4ml/kg/h for minor surgery (hernias, wrist ORIF, breast) • 6mL/kg for moderate surgery (gyn&obs, ortho, thoracics) • 8mL/kg for major procedures (GIT surgery, trauma) MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 20
- 21. Postoperative Fluid Therapy Based on the patients volume status and ongoing fluid losses Correct deficits, replace ongoing losses and give maintenance fluids Initial post op period: give an isotonic fluid solution After 24-48 hrs: 5% Dextrose 0.45% NS ( with added K) Daily assessment of volume status and electrolytes MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 21
- 22. ELECTROLYTE ABNORMALITIES HYPONATREMIA: SerumNa < 135 mEq/L Dilutional • High ECF volume • Excessive oral fluid intake or IVF therapy • Syndrome of inappropriate ADH • Drugs: antipsychotics, tricyclic antidepressantants, ACEI MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 22
- 23. Depletional: • Decreasedintake: low sodium diet • GI losses from vomiting • Prolonged nasogastric tube suctioning • Diarrhea • Diuretic use or primary renal disease MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 23
- 24. Manifestation of Hyponatremia MANIRABONAEmmanuel, MD, PGY-2, General Surgery Resident 24
- 25. Hyponatremia Management Mostcases can be treated with water restriction Severe cases need Na administration Symptomatic at levels < 120 mEq/L Neurologic symptoms: give 3% NS ( correct Na at a rate < 1mEq/l, until 130mEq/l) Rapid correct can lead to Central Pontine myelinolysis MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 25
- 26. Hypernatremia Na >145mEq/L Loss of free water or gain of Na Hypervolemic hypernatremia • Iatrogenic ( Na containing fluids) • NaHCO3 • Mineralocorticoid excess (hyperaldosteronism, Cushing syndrome) MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 26
- 27. Hypernatremia Normovolemic hypernatremia •Diabetic insipidus • Diuretic use and Renal disease • GI losses, skin losses Hypovolemic hypernatremia • GI losses- diarrhea • Fever and hyperventilation MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 27
- 28. Manifestation of Hypernatremia MANIRABONAEmmanuel, MD, PGY-2, General Surgery Resident 28
- 29. Management of Hypernatremia First, assess the volume status Treat hypovolemia with isotonic fluids Once volume is restored replace water deficit with a hypotonic solution : dextrose 5%, ¼ NS 5% Dextrose Slowly correct Na levels at a rate < 1mEq/h and 12 mEq/d (< 0.7 mEq/h in chronic hypernatremia) This is to prevent cerebral edema MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 29
- 30. POTASSIUM K+ iscritical to cardiac and neuromuscular function Factors that influence K+ distribution in ICF and ECF • Surgical stress • Injury • Acidosis • Tissue metabolism Normal serum K+: 3.5- 5.0 mEq/L MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 30
- 31. HYPERKALEMIA Serum level> 5.5 mmol/L Excessive potassium intake Increased release from cells Impaired excretion MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 31
- 32. Cont.… GI: nausea,vomiting, intestinal colic, diarrhea Neuromuscular: weakness, ascending paralysis, respiratory failure MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 32
- 33. Management of Hyperkalemia MANIRABONAEmmanuel, MD, PGY-2, General Surgery Resident 33
- 34. HYPOKALEMIA : Etiologies, S&S MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 34
- 35. Management of Hypokalemia •Check Magnesium level first • Asymptomatic patient with K > 3.0 mEq/L, oral K replacement may be sufficient. • Rate of IV infusion should not exceed 40 mEq/hr • May cause a burning sensation if given in peripheral IV. • Low flow rate of 10 mEq/hr or add small amount of lidocaine to the solution can decrease discomfort MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 35
- 36. HYPERCALCEMIA Normal totalserum calcium : 8.5- 10.5 mg /dl Ionized calcium > 4.2- 4.8 mg/dl Causes • Primary hyperparathyroidism ( 90% of patients) • Malignancy: bone metastasis, tumor secreting PTH Anorexia, nausea and vomiting, abdominal pain Weakness, confusion, coma, bone pain Hypertension, arrhythmias, polyuria, polydipsia MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 36
- 37. Management of Hypercalcemia Definitive management is the correction of the primary cause Correct volume deficits with IVF like NS followed by a loop diuretic In case of renal failure: hemodialysis Biphosphonates : reduce osteoclast mediated release of calcium. (bone metastasis) Exogenous calcitonin; can be used in short term treatment but not helpful in the long term MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 37
- 38. HYPOCALCEMIA Total calcium< 8.5 mEq/L or Ionized calcium < 4.2 mg/dl Etiologies o Pancreatitis, Necrotizing fasciitis, Tumor lysis syndrome o Renal failure, Hypoparathyroidism o Post parathyroid or thyroid surgery • Occurs in 1-2% after total thyroidectomy o Malignant related osteoblastic activity MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 38
- 39. Manifestation of Hypocalcemia Symptoms start with ionic fraction < 2.5 mg/dl Paresthesia of face and extremities ,Muscle cramps Carpopedal spasm, tetany, seizures, Hyperreflexia Chvostek’s sign: spasm from tapping over the facial nerve Trousseau sign: Carpal spam after inflating the BP cuff Decreased cardiac contractility, heart failure MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 39
- 40. Management of Hypocalcemia Repletion can be given oral or IV Oral calcium carbonate suspension 1250 mg/5ml q6 hours IV Calcium gluconate 2g IV over 1hr Recheck levels after 3 days Correct associated Magnesium, potassium and phosphate abnormalities MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 40
- 41. HYPERMAGNESEMIA Normal plasmaMg: 1.5-2.0 mEq/L Causes Of hypermagnesemia • Severe renal insufficiency • Magnesium containing antacids and laxatives S&S • Nausea and vomiting • Weakness, lethargy, hyporeflexia • Hypotension, cardiac arrest MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 41
- 42. Management of Hypermagnesemia Eliminate exogenous sources Correct volume deficits Correct acidosis Acute symptoms: calcium chloride 5-10 ml immediately to antagonize CVS effects Hemodialysis: if levels and symptoms persist MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 42
- 43. HYPOMAGNESEMIA Common inhospitalized patients and critically ill Alteration of intake Starvation, alcoholism, prolonged IVF therapy Increased renal excretion Alcohol abuse, diuretic use, amphotericin B, primary aldosteronism ,diarrhea, malabsorption, acute pancreatitis MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 43
- 44. Manifestation of Hypomagnesemia S&S • Hyperactive reflexes • Muscles tremors, tetany • Positive Chvostek's and trousseau signs • Delirium and seizures Hypomagnesemia can lead to hypocalcemia, persistent hypokalemia When they coexist, prompt correction of Mg2+ , to restore the other electrolytes MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 44
- 45. Management of Hypomagnesemia Mg level 1.0 -1.8 mEq/L • Magnesium sulfate 0.5 mEq/L in NS 250 ml infused over 24 hr for 3 days Mg < 1.0 mEq/L • Magnesium sulfate 1 mEq/l in NS 250 ml iv over 24 hr for 1 day, then 0.5 mEq/l in NS 250 ml over 24 hr for 2 days o Asymptomatic and mild • Oral: milk of magnesia 15 ml ( 49mEq/l ) q 24hours and hold if diarrhea MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 45
- 46. REFERENCES 1. Fluid andElectrolyte Management of the surgical patient, in Schwartzs Principles of Surgery, 10th Ed, chap 3, p65-81 2. Shock, Electrolytes and Fluids, in Sabiston Texbook of Surgery, 19th Ed, chap 5 3. Managing physiologic changes in the surgical patient, in Essential Surgery 5TH Ed, p 19-32 4. G P Joshi, Intraoperative fluid management. Available on UPTODATE. 5.N. Siparsky, Overview of Postoperative fluid therapy in adults. Available on UPTODATE. 6.Fluid, Electrolyte and Acid Base Balance in Elaine N. Marieb, Human Anatomy and Physiology, 7th Ed, chap 26 MANIRABONA Emmanuel, MD, PGY-2, General Surgery Resident 46