IV Access


IV Access, Intravenous Access, Venous Cannula Insertion, Vascular Access, Vascular Access Flow Rates, Intravenous Catheter Volume Flow Rate, Intravenous Pressure Bag

  • Types
  • Vascular Access Flow Rates
  1. Background
    1. Needle free connectors (e.g. Bionector, "bung") slow flow rates as much as 40% (esp. short, wide bore catheters)
    2. Pressure benefits all catheter flow rates (esp. longer catheters), increasing rates 60 to >100%
  2. Size 13F Dialysis Catheter
    1. Estimated Flow Rate to Gravity: 400 ml/min (infuses 1 L in 2.5 min)
  3. Size 14G Peripheral catheter
    1. Estimated Flow Rate to Gravity: 250 ml/min (infuses 1 L in 4 min)
  4. Size 16G Peripheral catheter
    1. Estimated Flow Rate to Gravity: 150 ml/min (infuses 1 L in 7 min)
  5. Size 8.5F Sheath Introducer
    1. Estimated Flow Rate to Gravity: 130 ml/min (infuses 1 L in 8 min)
  6. Size 18G Peripheral Catheter
    1. Estimated Flow Rate to Gravity: 100 ml/min (infuses 1 L in 10 min)
  7. Size 16G Distal Port Triple Lumen Central Catheter
    1. Estimated Flow Rate to Gravity: 70 ml/min (infuses 1 L in 15 min)
  8. Size 15G Intraosseous Needle (adult tibia)
    1. Estimated Flow Rate to pressure (via syringe): 60–100 ml/min of crystalloid
  9. References
    1. Fluid administration device flow rates (LITFL)
    2. Azim (2023) Crit Dec Emerg Med 37(4): 23-9
    3. Reddick (2011) Emerg Med J 28(3):201-2 +PMID: 20581377 [PubMed]
  • Approach
  • Peripheral Access
  1. Peripheral IV Access (default initial line)
    1. IV Gauge determines maximal flow rates (18 G or larger is preferred)
      1. See above
    2. Initial Resuscitation with fluids
      1. Fluid infusion via 18 gauge peripheral IV is faster than via a triple lumen central catheter
    3. Medication administration including antibiotics
    4. Intravenous Contrast administration (reliable 18 gauge IV needed for CTA, PE studies)
    5. Initial Vasopressors may be used peripherally if reliable large bore IV (until central access is obtained)
    6. Allows for venous lab samples on placement and later
      1. Requires wasting part of sample, and then Flushing line
  2. Intraosseous Access
    1. Rapid landmark based placement with multiple available sites (e.g. proximal tibia, Humerus)
    2. Emergent Vascular Access for Resuscitation when peripheral IV cannot be immediately placed
    3. Allows for infusion of most fluids and medications including Vasopressors (but not Sodium Bicarbonate)
    4. Limited flow rates even with pressure bags (incapable of rapid infusion)
  3. Midline Venous Catheter (Ultrasound-Guided Antecubital Line)
    1. Alternative to central venous access when standard peripheral lines are difficult
    2. Extravasation is more common with deep brachial vein IVs
  4. Rapid Infusion Catheter (RIC Line)
    1. Converts a 18-20 gauge peripheral IV into a large bore line (8 Fr)
      1. Seldinger wire is threaded through peripheral line and peripheral IV is removed
      2. Skin is nicked at IV entry site and dilator is threaded over wire and through skin
      3. Catheter is threaded over wire and into vein and wire is removed
    2. Allows for high flow rates via peripheral line
    3. Risk of destroying peripheral vein by threading it with too large of a catheter
  • Approach
  • Central Access
  1. See Central IV Access
  2. Background
    1. Central Lines are sewn in place and typically more secure than peripheral lines which may be dislodged
    2. Internal Jugular Veins are preferred central access points
      1. However, in Resuscitation, consider femoral lines which are out of way of Resuscitation efforts
      2. Convert femoral lines to other sites in first 48 hours
  3. Central Line Types
    1. Triple Lumen Catheters
      1. Best for infusing multiple medications (including Vasopressors)
      2. Slower infusion rates (under pressure) than 18 gauge peripheral IVs
    2. Introducer Catheters
      1. Largest bore of the central catheter options offering high infusion rates
      2. Weingart recommends bypassing side port with commercially available product
    3. Hemodialysis Catheters
      1. Large bore catheter (12-13 french) with 2 ports
  • Types
  • Pressure Bag
  1. Standard Pressure Bag
    1. Maximum pressure 300 mmHg (requires repeatedly repumping up bag)
    2. Superior to manually squeezing IV fluid bags (unable to reach the same pressures manually)
    3. When using large pressure bags (1 Liter) on smaller IV fluid bags
      1. Position the IV fluid bag at the inferior aspect of the pressure bag
  2. Mechanical Pressure Device (Belmont rapid infuser, Level 1 Infuser)
    1. Maximum pressure equivalent to standard pressure bag
    2. Applies constant pressure throughout infusion regardless of remaining fluid volume (unlike standard pressure bag)
    3. Also functions as a fluid warmer
  3. References
    1. Weingart and Swaminathan (2023) EM:Rap 23(11)
  • References
  1. Weingart and Swaminathan in Herbert (2021) EM:Rap 21(4): 5-7