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Vascular Access Overview 

  • Required to administer IV fluids and medications
  • Useful in obtaining blood sampling for lab tests
  • Types of access depends on medications that need to be administered and anticipated length of use
    • Central vs. peripheral
  • Vascular acces can be utilized for invasive monitoring in critically ill patients 



Peripheral catheters



  • Most commonly used catheter in the acute care setting
  • Usually placed in a vein of the hand or arm, placed distally if possible
  • CDC Guidelines recommend changing of catheter every 96 hours
  • Infection, Phlebitis, Extravasation, Infiltration, Air embolism, Hemorrhage, Hematoma 


Peripherally Inserted Central Catheters (PICC)


  • Good for patietns who are staying long IV acces
  • Alternative to Subclav lines, internal jugular lines or femoral lines, which have higher rates of infection
  • Insertions requires specialised training
  • Complications
    • Catheter occlusion, phlebitis, hemorrhage, thrombosis, infection



Central Venous Catheters

  • Allows administrations of large volumes of fluid, blood products, TPN, caustics, vasopressors, chemo
  • Capabe of monitoring hemodynamics CVP
  • Placed into a large vein in the neck (internal jugular vein). chest or groin
  • Complications
    • Pneumothorax, Thrombosis, Infections, Air embolism 



  • Entry into the bone marrow to provide a non-collapsible entry point into the systemic venous system
  •  Any medication that can be administered via IV can be administered via IO
  • Useful in emergency situations when IV access cannot be obtained
  • Requires specialized training
  • EM nurses, EMT
  • Can be utilized for ~24 hours
  • Complicatons 
    • Fat embolism, fracture, osteomyelitis, compartment syndrome, Abscess, skin necrosis


Complications of IV therapy

  • Infiltration
    • Non-vesicant fluid leaks into surrounding tissue
  • Infections
    • Punture interrupts skin integrity
  • Phlebitis
    • Inflammation of the vein
  • Thromophlebitis
    • Irritation of vein with clot formation
  • Extravascation 
    • Leakage of vesicant fluid into surrounding tissue 


Comparison  fo Options for Vascular Access


Total Body Water

1 liter of fluid =?

70 kg male =

  • For clinical purposes, total body fluids = 60% body weight for adults 
  • Percent decreases as body fat increases
  • decreases with Age 
  • For calculations, use hydrated (normal) weight unless patient is obese (>20% of IBW) use IBW
  • 2.2Ibs(1 kg)
  • 42 liters 


Intracellular fluid 

  • Water within cells
  • 2/3 of TBW
  • 40% of body weight
  • Rich in electrolytes
    • K, Mg, Phosphates, Proteins


Extracellular fluid (ECF) 


  • Fluid outside cell
    • Rich in Sodium, Chloride, bicarb
  • 1/3 of TBW
  • Made up of two major fluid sub compartements 
    • Interstitual/ lymph 
      • Fluid space between cells
    • Intravascular 


Fluids, Electrolytes, Acid-Base losses


  • Sensible
    • Urine, stool
    • Water, sodium, K
  • Insensible
    • Lung, evaporation through skin, fever
    • Mostly water and a little Na+
  • Other
    • Nasogastric tube suction
    • Nasojejunal tubes
    • Drains
    • Fistula tracts
    • Burns 


Intravascular Depletion Acute problem

Signs/Symptoms and causes 


TBW depletion Chronic problem 


Replacement therapy Determining the Needs

  • Ongoing exceptional loss
    • If ongoing problems are not accounted for, a second insufficiency will develop soon after correction of the current deficiency 
    • Replacement regimen should match as closely as possible both the amount and composition of the exceptional losses
    • At minimum, realize that exceptional fluid losses maybe be occuring and be particularly vigilant to monitor these patients for S/S of fluid depletion 


Maintenance Basal Requirements 

Neonate (1-10 kg)

Child (10-20)

Adults > 20 

  • 100 ml/kg
  • 1000 ml + 50 ml for each kg > 10 
  • 1500 mL + 20 ml for each kg >20 '
  • For sensible losses in hospitalized pts not taking much PO



Isotonic fluids 

(310 mEq/L) 


fluid doesnt shift from ECF to ICF 




Hypertonic > 376 can help?

Draws water out of cells into ECF

Help stabalize bp, increase urine output, and reduce edema


Hypotonic < 250 

Water is pulled from vascular compartments into interstitial fluid is diluted 


Crystalloid solutions

  • Electrolyte solutions supply water and sodium to maintain the osmotic gradient between ICF and ECF
  • Plamsa volume- expanding capability of crystalloid is directly related to its sodium concentration
  • D5W: Free water


IV fluid comparisons


IV fluid comparisons continued 


Choice of approptiate fluid?


Pts with impaired tissue perfusion?

Standard therapy?

  • Define primary type of fluid problem 
    • TBW depletion vs. ECF depletion 
  • ITP- immediate therpeutic goal 
    • Return volume to intravascular space and ECF compartment
    • Standard therapy is to administer normal saline quickly (150-500 mL/hr) until S/S of impaired tissue perfusion have minimized or disappeared 
      • Pt may be switched to a more hypotonic solution 


In pts demonstrating impaired tissue perfusion?

  • LR is an alternative, however, lactate may be problematic during massive prolonged infusions 
  • In severe cases, a solution may be indicated that increases in oncotic pressire within the vasculature space
    • Colloid 
    • blood cells (specially indacted if oxygen-carrying capacity of blood is compromised) 


In patients with elevated plasma osmolarity and serum sodium concentrations 

  • In patients demonstrating elevated plasma osmolality and serum sodium concentrations
  • Virtually always have a water-deficit problem and, in the absence of S/S of impaired tissue perfusion, primarily need hydration (water) therapy
  •  Hypotonic solutions: more efficient at replenishing the ICF than do isotonic solutions and reduce the plasma osmolality more quickly 
  •  Solution should have a lower sodium concentration than the patient's serum, but do not drop the serum sodium too quickly (CAUTION - cerebral edema)
  • D5½ NS is a commonly-used general rehydration solution; hypertonic or colloidal solutions have no role in treating TBW depletion


Monitoring therapy


Therapuetic goal:  resolve S/S of fluid deficit and normalize lab values as much as possible 

  • Physical S/S (thirst, sunken fontanelles, CNS problems)
  • Orthostatic blood pressure 
  • Pulse rate
  • Wt changes
  • Blood chnages
  • Blood chemistries 
  • FLuid input vs. fluid output
  • CVP, PCWP, cardiac output (ICU pts) 



Monitoring therapy?

Replenish fluids ______ in conditions that may?


  • more cautiously in conditions that may predispose a pt to fluid overload
    • Renal failure 
    • Cardiac failure 
    • Hepatic failure 
    • Elderly 


Fluid deficiency summary? 


Summary - fluid overload 

  • Excess intake
    • Excess IV fluids 
    • Blood/plasma use
    • hypertonic fluids 
    • Excess dietary sodium 
    • Water intoxication 
    • Remobilization of edema
  • Inadequate Output
    • CHF
    • Cirrhosis
    • Nephrotic syndrome 
    • Hyperaldosteronism
    • Low dietart protein
    • Steroid use 


Electrolyte distribution 

Total # of anions = ? 

Critical that cell membrane keep? 

___ concentrations reflect total body stores of ECF electrolytes rather than that of ICF electrolytes

  • total number of cations in each fluid compartment 
  • keep the ICF and ECF separate and biochem distinct
  • Serum  


Serum electrolyte normal values?