emergency med

  1. Total body water
    • 50-70% of total body weight
    • Average M>F
    • Lean muscle contains h20>adipose
    • Deceases w/ age
  2. Body water purpose
    • Transport nutrients, gases and waste in/out cells
    • Eliminate wastes
    • Regulate body temp
  3. ICF
    • Approx. 40% body weight
    • High in K, Mg
    • Low Na, Cl
  4. ECF
    • 20% tbw
    • Low K,MG
    • High Na Cl
  5. ECF divisions
    • Interstitial fluid
    • Plasma
    • Fluid of bone and connective tissue
    • Transcellular fluid
  6. K, Mg fluid levels
    • High ICF
    • Low ECF
  7. Interstitial fluid
    • ECF
    • LOW PROTEIN LEVEL
    • “Fluid that fills the cracks”
    • Approximately 10.5L
    • It is the link between the intracellular fluid and intravascular space
    • Oxygen, nutrients, wastes and chemical messengers all pass through
    • Has the same compositional characteristics of ECF
    • Lymph
  8. Intravascular
    • HIGH PROTEIN CONTENT
    • CONTAINS RED AND WHITE CELLS
    • ONLY major fluid that exists as real collection all in 1 location
    • Plasma
    • High bulk flow
  9. Bone and ct fluid
    Mobilized very slowly
  10. Transcellular fluid
    • Body fluids formed from transport activities of cells
    • w/in epithelial lined spaces
    • csf, urine, aqueous humor
    • joint fluid
  11. Goals of Fluid Therapy
    • Replace volume losses
    • Protect organs from hypoperfusion injuries
    • Maintain osmolarity
    • Maintain acid-base and electrolyte balance
  12. Colloid Solutions
    • Contain large molecules that do NOT pass through semipermeable membranes
    • remain in the intravascular space
    • expand the intravascular volume
    • draw fluid in via their higher oncotic pressure
  13. Crystalloid Solutions
    • Contain small molecules that flow easily across semipermeable membranes
    • allowing for transfer from the blood stream into the cells and body tissues
    • Increases fluid in BOTH interstitial and intravascular space
    • Approximately 25% remains in the intravascular space 1hr after administration
  14. Osmolality
    describes the solute concentration in body fluid by particles per Kilogram (# mOsm/Kg)
  15. Osmolarity
    • describes the solute concentration in body fluid by particles per Liter (# mOsm/L)
    • - Normal 270-300 mOsm/L or Kg
  16. Isotonic
    • when a fluid is fairly EQUIVALENT in particle concentration to normal plasma osmolarity
    • (270-300 mOsm/L)
    • Osmotic pressure is constant on both inside and outside of cells
    • fluid in each compartment remains the same (No shift occurs)
    • Fluid does not move into the intracellular space
    • remains in the extracellular space (intravascular and interstitial)
    • Examples: 0.9% Normal Saline (0.9 NS), Lactated Ringers (LR), Ringer’s and 5% Dextrose in Water (D5W)
  17. Hypotonic
    when a fluid is LESS concentrated than normal plasma osmolarity(<270 mOsm/L)
  18. Hypertonic
    when a fluid is MORE concentrated than normal plasma osmolarity (>300 mOsm/L)
  19. Normal Saline 0.9%
    • - Basically salt water, it contains 154 mEq/L of Na and Cl; isotonic
    • - Increases the volume of the extracellular space
    • - FLUID OF CHOICE FOR RESUCSCITATION EFFORTS
    • - ONLY fluid that can be administered with blood products in the same line
  20. NS when to GIVE
    • very good for replacing fluid volume deficit from
    • hemorrhage, severe vomiting or diarrhea,
    • heavy drainage from GI suction/fistulas/ostomies,
    • draining wounds, shock, mild hyponatremia,
    • hypercalcemia and fluid challenge
  21. NS caution use
    • in your fragile patients such as the elderly
    • cardiac and renal disease as there is potential for volume overload
  22. Lactated Ringer’s (LR)
    • The MOST physiologically adaptable fluid
    • it’s electrolyte content is most closely related to the composition of the body’s blood plasma
    • metabolized in the liver which converts the lactate to bicarb (Alkalizing solution)
  23. Lactated ringer’s Contents
    130 mEq/L Na, 109 mEq/L Cl, 4 mEq/L K, 3 mEq/L Ca
  24. LR When to GIVE
    • another first choice for fluid resuscitation,
    • similar clinical situations as 0.9% NS
    • also used pre/post op, metabolic acidosis
  25. LR When to use CAUTIOUSLY
    • patient’s with liver disease or renal disease
    • HOLD if pH is >7.5
  26. Isotonic Fluids: Ringer’s
    • - Similar in make up to LR however doesn’t have the lactate therefore it doesn’t have the same liver contraindications
    • - Not an alkalizing agent, no pH restriction
  27. 5% Dextrose in Water (D5W)
    • Basically sugar water, contains 170 calories/L and no electrolytes
    • Isotonic or Hypotonic…
    • Provides “Free Water”
    • Expands BOTH intracellular and extracellular compartments at the same time
    • Good for hypernatremia, most often used as a maintenance fluid
    • Although it does supply some calories, it’s not enough for prolonged use
  28. D5W NOT used
    • treat fluid water deficit
    • 1. dilutes plasma electrolyte concentration
    • 2. it won’t stay in the intravascular space
  29. D5W Contraindicated
    • In early post op because the body’s reaction to the surgical stress may cause an increase in ADH
    • In patients with known or suspected increased intracranial pressure (ICP) due to it’s hypotonic properties following metabolism
  30. Free water
    • unbound water molecules small enough to pass through membrane pores to the intracellular space
    • provided by D5W and hypotonic fluids
  31. Isotonic Fluids… Final thoughts
    • Patients can quickly develop hypervolemia following rapid or over infusion of isotonic fluids.
    • Be MINDFUL!!!
    • Monitor – Vitals, PE , Labs, I&O’s
  32. Hypotonic Fluids
    • Lower concentration or tonicity of solutes
    • Osmolarity <250 mOsm/L
    • Infusion causes a DECREASE in serum osmolarity within the vascular space
    • Fluid will shift from the intravascular space to BOTH the intracellular and interstitial compartments.
    • “Cell Hydration”
    • BE AWARE the fluid WILL shift which can deplete the fluid within the circulatory system, worsening hypotension and causing circulatory collapse
    • Examples: 0.45% NS, 0.2% NS, 0.33% NS, 2.5% Dextrose in Water
  33. Hypotonic Fluids CONTINUED
    • Provide free water, NaCl, and replace natural fluid loss
    • Assist with maintaining daily body fluids and electrolytes
    • Help Kidneys excrete excess fluids and electrolytes
    • Usually used during conditions that cause intracellular dehydration (DKA, hyperosmolar hyperglycemic state)
    • NEVER GIVE: patients at risk for increased ICP or to trauma or burn victims
  34. Hypertonic Fluids
    • Higher tonicity/solution concentration causing an unequal pressure gradient between the inside and outside of cells
    • Draws fluid OUT of the intracellular space therefore increasing extracellular fluid volume
    • “Volume Expanders” – increases BP
    • Reduces interstitial and endothelial edema
    • Osmolarity >375 mOsm/L
    • Examples: 3% NS, 5% NS, D10W, D20W, D50W
  35. Concentrated NS
    • Moderate to severe Hyponatremia,
    • patient’s with cerebral edema
  36. D10W
    provides free water and calories (340 calories/L)
  37. D20W
    acts as an osmotic diuretic
  38. D50W
    • highly concentrated sugar water
    • given rapidly via IV bolus to treat severe hypoglycemia
  39. Hypertonic Fluids Continued
    • Maintain vigilance
    • potential for causing intravascular volume overload and pulmonary edema.
    • GO SLOW
    • Prescription for their use should include:
    • why administering, total volume to be infused, rate of infusion, stop time
    • Also you can always add Dextrose to other solutions to get benefit of calories plus electrolytes, with addition the solution will be made slightly hypertonic
  40. Colloid Solutions
    • Contain molecules too large to pass through semipermeable membranes
    • Volume Expanders - they draw fluid from the interstitial space into the intravascular compartment
    • Similar to hypertonic solutions
    • require administration of LESS total volume
    • their effects last LONGER compared to crystalloids
    • Examples: Albumin, Dextran, Hetastarch
  41. Colloid Solutions…. 5% Albumin
    • Most commonly used colloid solution
    • Contains plasma protein fractions obtained from human plasma
    • Works to rapidly expand the plasma volume
    • Expensive
    • BLOOD product so has same protocols and risks with administration
  42. 25% albumin
    this draws out 4x its volume from the interstitial fluid into the intravascular compartment in 15 min!
  43. 5% albumin When to GIVE
    • Patient’s with hypoproteinemia/malnourished,
    • patient’s who require intravascular volume expansion and cannot tolerate large infusions of crystalloids,
    • shock, post surgery – especially ortho/reconstructive surgery
  44. Synthetic Colloid Solutions
    • Dextran
    • Hetastarch/6% hespan
  45. Dextran:
    • 1. Available in saline or glucose preparations
    • 2. Can INTERFERE with blood typing
  46. Hetastarch/6% Hespan:
    • 1. Contains some Na and Cl
    • 2. LESS expensive than albumin
    • 3. Effects last 24-36hrs

    • Colloids: Last Tidbits
    • Need an 18G IV to infuse
    • Colloid solutions can interfere with platelet function, increasing bleeding times. Monitor patient’s coagulation indexes
    • Monitor closely for intravascular volume overload
  47. Sensible fluid loss
    loss that can be measured, loss from the GI and GU tract.
  48. Insensible fluid loss
    cannot be measured, loss from skin and lungs
  49. Clinical Assessment of Volume Status
    • Most of your patient’s will present with some degree of dehydration
    • Red Flags: vomiting, diarrhea, fever, anorexia, AMS and decreased urine output
    • Tachycardia and Hypotension are LATE findings
    • Lab values are usually not reliable indicators
  50. Calculating Fluid Deficit
    • calculated based on number of Hrs NPO
    • Hrs NPO x (60 +weight in kg - 20) ml = Fluid deficit
  51. Calculating Fluid Maintenance requirement for normal adults
    • 60ml + (weight in kg -20) ml = Fluids/Hr
    • OR
    • 4-2-1 Rule
    • 4ml/kg/hr for first 10kg
    • 2ml/kg/hr for next 10kg
    • 1ml/kg/hr therafter
  52. To estimate Daily Fluid requirement,
    use the 100-50-20 Rule
  53. Calculating Fluid Requirements in the Obese Pt
    • Calculate for their IDEAL body weight.
    • Men: 106 + 6lbs for every inch over 60 in (5ft)
    • Women: 100 + 5lbs for every inch over 60 in (5ft)
  54. End Points to Resuscitation
    • UOP 30-50 ml/hr or 0.5/kg/hr
    • CVP 8-12 mmHg
    • MAP >65 mm Hg
    • ScVO2 >70%
  55. Central line Indications
    • Central venous monitoring
    • Volume resuscitation
    • Cardiac arrest
    • Lack of peripheral access
    • Infusion of concentrated solutions/vasopressors
    • Chemotherapy,
    • epinephrine, dopamine, norepinephrine, vasopressin
    • Placement of transcutaneous pacemaker
    • Hemodialysis
  56. Central line Relative Contraindications
    • Anticoagulated/Bleeding disorderso
    • Combative patients
    • Distorted anatomy-US may help with this
    • Cellulitis/Burns/Vasculitis at site
  57. Central line Complications
    • Air embolus
    • Arterial entry
    • Hematoma & Blood clot
    • Infection
    • Dysrhythmias-can cause V tach with IJ placement
    • Nerve injury
    • Pneumothorax/Hemathorax
    • Bowel or bladder perforation
  58. Diagnostic errors
    • Delayed, wrong, missed entirely
    • 1 in 10 wrong
    • 40-80K deaths US yrly
    • Leading cause of med malpractice
  59. Diagnostic error causes
    • Inaccurate assessment of hx and PE
    • Wrong interpretation of dx test
    • Overreliance on clinical axiom
    • Cognitive biases
  60. Anchoring bias
    • Locking on to salient features in pts initial presentation
    • Failing to adjust in light of later info
  61. Availability bias
    Judging things to be more likely if they readily come to mind
  62. Confirmation bias
    Looking for evidence to support dx rather than looking for evidence to rebut it
  63. Diagnosis momentum
    Allowing dx labe that has been attached to pt to gather steam ->wrongful exclusion
  64. Overconfidence bias
    Believing we know more than we do and acting on incomplete data
  65. Premature closure
    Accepting a diagnosis before it is fully verified
  66. Search satisfying bias
    Calling off the search once something is found
  67. I VINDICATE
    • Idiopathinc/psych
    • Vascular
    • Infectious or inflammatory
    • Neoplastic
    • Degenerative
    • Iatrogenci ( drug/toxin)
    • Congenital
    • Allergic/autoimmune
    • Trauma
    • Endocrine/metabolic
Author
alyspins
ID
307288
Card Set
emergency med
Description
emergency med
Updated