Vascular Access, Body Fluids, and Fluid Therapy

Transcription

1 Introduction Vascular Access, Body Fluids, and Fluid Therapy Garret Pachtinger, VMD, DACVECC COO, VetGirl Garret Pachtinger, VMD, DACVECC COO, VetGirl Justine A. Lee, DVM, DACVECC, DABT CEO, VetGirl Introduction CE Certificates Justine A. Lee, DVM, DACVECC, DABT CEO, VetGirl ed to you within 48 hours of webinar Active participation = no quiz Watching video later, must complete quiz / contact with ANY questions garret@vetgirlontherun.com justine@vetgirlontherun.com Overview Vascular Access Vascular access Body fluid compartments Goals of fluid therapy Fluid therapy options Peripheral venous catheterization Central venous catheters Intraosseous catheterization Arterial catheters 1

2 Vascular Access Venous Catheters Indications Sites Peripheral vs. Central Types of catheters Catheter through the needle Needle through the catheter Over the wire systems Potential complications Sterile preparation Proper positioning Patient restraint Insertion of catheter Peripheral Catheter Placement Securing the catheter henous%20vein.jpg Peripheral Catheter Placement Peripheral Catheter Placement Cephalic Vein Catheter Through the Needle Combined Over / Through the Needle Catheters Short catheter is placed Long catheter fed sterilely through short catheter 2

3 Multi-Lumen Catheters Central Line Complications Arterial Catheters Hemorrhage Phlebitis Infection Thrombosis Catheter emboli Extravasation of fluids Indications Sites Potential complications Careful in cats! Intraosseous Catheters Indications Sites Devices What if it won t flush? Rotate needle degrees Pull back 1-2 mm Check placement with radiographs Stylet (core in hub of catheter) Flush with pressure Procedure Potential complications Charlie 3

4 Body Fluid Compartments Fluid Balance In health, fluid balance determined by balances between: 1. Forces favoring reabsorption Increased oncotic pressure Decreased hydrostatic pressure 2. Forces favoring filtration Decreased oncotic pressure Increased hydrostatic pressure Why do we need fluid therapy? Shock resuscitation Rehydration Maintenance requirements Replacement of ongoing losses Hypovolemia = Dehydration Dehydration Dehydration Clinical Signs Estimate of dehydration Normal <5% Dry mucous membranes 5% Reduced skin turgor 6-8% Increased heart rate 8-10% Weak pulses 10-12% Collapse, shock 12-15% 4

5 Is skin turgor always the best? Clinical signs of Hypovolemia Pale mucous membranes Prolonged capillary refill time Cold extremities Poor peripheral pulse quality Tachycardia Tachypnea Dull mentation Decreased urine output Shock Fluid Therapy? Fluid Therapy MAP SVR SV PL AL Dehydration? D 2 O CO HR contractility % dehydration x wt in kg = L Hg, SpO 2 CaO 2 PaO 2 20 kg patient is 10% dehydrated 20 kg x.10 = 2.0 liters (2000 ml) Example: 20 kg dog who is 8% dehydrated requires 1.6 L Fluid Therapy SHOCK?!? Yes? DOG: 90 ml x wt in kg = ml CAT: 60 ml x wt in kg = ml To Effect What rate? Calculations: Shock: ml bolus to effect THEN. Dehydration: ml/hr + Maintenance: ml/hr + Ongoing Losses: ml/hr =Initial Fluid Rate ml/hr 5

6 Fluid Delivery Drop Size Formula 10 drop/ml (ml/hr) 6 = drop/min 15 drop/ml (ml/hr) 4 = drop/min 20 drop/ml (ml/hr) 3 = drop/min 60 drop/ml (ml/hr) 1 = drop/min What Effect? Reduction in heart rate Improvement in pulse quality Improvement in MM color Return of CRT to normal Improvement of mentation Resolution of hypothermia Oral Subcutaneous Intraperitoneal Intravenous Intraosseous What route? Bowl of water Voluntary Naso-esophageal tubes Oral Hospitalized cats NOT respiratory distress INAPPROPRIATE FOR SHOCK OR VOMITING PATIENTS! Rehydration NOT for shock Subcutaneous Intraperitoneal The rate of absorption? Complications? Advantages? Only isotonic solutions Avoid dextrose Maintain hydration in renal failure patients 6

7 Intravenous Fluid Therapy Options Preferred route for hypovolemia Severe dehydration Maintenance and ongoing losses Any type of fluid, supplements Colloids Hypertonic solutions Types of fluids available: Isotonic crystalloids Synthetic colloids Hypertonic saline (7.5%) Blood products Fresh Whole Blood Plasma Packed Red Blood Cells Albumin Oxyglobin Isotonic crystalloids Electrolyte containing fluids with an electrolyte composition similar to the extracellular fluid Same osmolarity as plasma ( mosm/l) Examples include: 0.9% saline Lactated Ringer s solution Normosol-R Isotonic Crystalloids Plasmalyte-148 Synthetic Colloids High molecular weight particles Suspended in isotonic crystalloid solution Help to pull fluid into the vascular space Increases blood volume by a greater amount than that infused Synthetic Colloid Solutions Synthetic Colloid Solutions Hydroxyethyl starch *Hetastarch* Hespan, Hextend Tetrastarch VetStarch Voluven Pentastarch Advantages: Much more effective support of COP Prolonged duration of effect Bolus minimal reactions Disadvantages: Only for oncotic support none of the other advantages of plasma apply! PentaLyte, HAESteril 7

8 Dextran 70 Hetastarch ½ life of hrs Average molecular weight: 70,000 kd May interfere with accurate blood cross-matching. Coagulopathy Dilutional platelet adhesion Inhibits Factor VIII and vwf A synthetic high molecular weight starch polymer M w of 670 kd and 0.75 degree of substitution Relatively long duration of action May cause restlessness and salivation in some cats. Soapbox VetStarch Recommend maximum daily dose of ml/kg If higher doses are needed, supplement with fresh frozen plasma to provide coagulation factors M w of 130 kd and a 0.4 degree of substitution. Compared, Hetastarch has a M w of 670 kd and 0.75 degree of substitution Reduces coagulation effects Less risk of acute kidney injury VetStarch / Hetastarch Acute resuscitation, bolus dose: ml/kg in the dog (most commonly 5) ml/kg in the cat (most commonly 2-3) Followed by re-assessment HES - up to 20 ml/ kg/day* VetStarch - rates of up to 50 ml/kg/day. Refractometry Gives an indication of hypoproteinemia and thus an idea about COP Cannot be used reliably once artificial colloids have been administered Artificial colloids have refractometry reading of g/dl 8

9 Assessment of therapy Only method to directly measures patient s COP Patient response to treatment Basic and advanced monitoring tools Edema improving, worsening? Tissue perfusion corrected? Beneficial or harmful effect? Why use it? COP 100 Hypertonic Efficacy Side effects Sensitization? Albumin Therapy Canine Albumin Oxyglobin Plasma obtained via plasmapheresis Albumin fractionated out and lyophilized 5g albumin/vial (~that of 200mL of plasma) Shelf-life 15 months; store in refrigerator Limited studies A sterile, ultrapurified, stroma-free, polymerized bovine hemoglobin solution (Hb~13gm/dL) Hyperoncotic, isotonic, non-antigenic Stored at room temperature for up to 2 years Dose = 10-30mL/kg Side effects Colloid Chart Hypertonic Saline Colloid Mean MW (KDa) Molar substitu tion COP (mmhg) 5% Human albumin 69 N/A 23.2± % Human albumin 69 N/A > 200 Canine fresh frozen plasma 69 N/A 17.1± 0.6 6% Hetastarch in 0.9% NaCl ± 0.2 6% Hetastarch in balance electrolyte solution ± 0.1 Hextend 6% Voluven ± 0.8 6% Vetstarch * Dose 5 ml/kg over 5-10 minutes Indications Small volume resuscitation, head trauma Potential side effects Dehydration, hypernatremia (additional fluid therapy should be used) 9

10 Turbo-Starch Blood products for resuscitation? 17 mls of 23.5% NaCl with 43 mls of colloid = 60 mls of 7.5% NaCl-Dextran solution Dose s 4-7 ml/kg for dogs 2-4 ml/kg for cats Prolongs the effect of the resuscitation fluids (60-90 min) Het/Vetstarch or Dextran MAP D 2 O SVR CO CaO 2 PL SV AL contractility HR Hg, SpO 2 PaO 2 Blood Products Shock Fluid Therapy Dependent on the underlying disease process What losses do they tolerate? When do they require a blood transfusion? What products do they need? Fresh whole blood? Packed red blood cells (Fresh) frozen plasma Goals? Keep the Hct >20-25% Clotting times within the normal range Time for administration: Typically over 1-4 hours Bolus? Shock Fluid Therapy Fresh Whole Blood Red blood cells Clotting factors Platelets Dose = ml/kg Indicated in animals with thrombocytopenia-induced bleeding or massive hemorrhage Shock Fluid Therapy Packed Red Blood Cells Only red blood cells Dose = ml/kg Hct drops <20-25% acutely Transfusion trigger? Massive hemorrhage? 10

11 Shock Fluid Therapy Fresh Frozen Plasma (FFP) Plasma separated and frozen within 6 hours and <1 year old Contains clotting factors, albumin, and other proteins Dose = ml/kg Indicated in animals that require clotting factors Colloidal properties? Shock Fluid Therapy Frozen Plasma Plasma separated and frozen <6 hours from time drawn or FFP that is >1 year old Contains stable clotting factors only (factor V, VIII, and VWF are not stable and therefore not present) Dose = ml/kg Indicated for: Rodenticide poisoning Colloid replacement Transfusion Reactions Autotransfusion Excessive hemorrhage Pleural cavity Peritoneal cavity Contraindications - hemorrhage due to: Neoplasia Septic process Chronic effusions Monitoring Monitoring Reassess HR RR / effort Pulse quality, MM color, CRT Mental status Temperature Uncontrolled hemorrhage? Abnormal compensatory mechanisms? Additional therapeutic and monitoring strategies CVP ABP EKG Repeated measurements of PCV, TS, BG, electrolytes and acid base are indicated 11

12 Conclusions Variety of vascular access locations and techniques It is important to understand the distribution of body water when assessing animals and formulating fluid plans The animal with evidence of cardiovascular shock requires prompt treatment and frequent reassessment November: Where is VetGirl going to be? Check out our upcoming 2013 Virginia VMA, Greenbriar, VA (Dr. Lee) lectures here: Latin America VECCS, Ecuador (Dr. Lee) WSAVA, Bangkok, Thailand (Dr. Pachtinger) December: SE Michigan VMA, Detroit, MI (Dr. Lee) Novotech, Madrid, Spain (Dr. Lee) January: NAVC, Orlando, FL (Dr. Lee, Dr. Pachtinger) AMVW, Toronto, Canada (Dr. Lee) February: International Veterinary Seminars, Curacao (Dr. Lee) WVC, Las Vegas (Dr. Lee) March: Montreal (Dr. Lee) AAHA, Nashville, TN (Dr. Lee) Connecticut VMA, Hartfort, CT (Dr. Lee) Exhibiting debut! January 2014: NAVC, Orlando, FL Stop by and get a free VetGirl sticker and water bottle! Questions? GARRET@VETGIRLONTHERUN.COM VetGirlOnTheRun 12