Anaesthesia And Fluids Flashcards
What is normal serum osmolarity
275 - 295 mOsm/L
Why is normal saline not routinely given in fluid resuscitation, especially septic patients? (3)
- hyperchloremic metabolic acidosis
- renal dysfunction
- mesenteric hypoperfusion
Which group of fluids is contraindicated in shock?
Hydroxyethyl starches aka voluven. Type of synthetic colloid
Resuscitation fluid indications and examples?
To provide plasma volume expansion and improve tissue perfusion . needs to contain sodium. Isotonic
Eg ringer’s, plasmalyte B
Maintenance fluid indications and examples?
Provide basic daily requirements of water, electrolytes and some caloric support in patients unable to use oral intake route
Eg 5-10 % maintelyte
Rehydration fluid indications and examples?
Indicated purely to restore water deficits. Electrolytes have to be added depending on specific deficits
Eg rehydration solution, 5% dextrose
Replacement redistribution fluid indications and examples?
Assist with daily balance of water by adding or subtracting from maintenance needs in cases with superimposed loses or excesses
Eg ringer’s, plasmalyte B
Name 3 classes of fluids and 3 examples of each
• Crystalloid’s.: ringers lactate, 0,9% Nacl normal saline, plasmalyle B (balsol), maintelyte 5-10%, 5 and 10% dextrose in water, 5 % Hypertonic saline, rehydration solution, 1/2 dd (half Darrows and dextrose Paeds) , neonatalyte
. synthetic colloids: starches HES (voluven., volulyte) and gelatine (gelofusine)
• natural colloids: human albumin 4 % (albusol), blood components (RC, FFP, platelets, freeze dried plasma), especial fractions (cryoprecipitates, factor concentrates eg haemosolvate, haemosolvex, immunoglobulins
State the composition (Na, Cl, k, buffer, ca, mg, glucose, pH, osmolality ) of plasma
• Na 135 - 145 •cl 95-105 . K 3,5-5,3 • buffer hco3 24-32 • Ca 2,2-2,6 . Mg 0,8-1,2 • glucose 3,5-5,5 • ph 7,35-7,45 .0sm 275-295
State the composition (Na, Cl, k, buffer, ca, mg, glucose, pH, osmolality ) of ringers lactate and uses
• Na 130 ( slightly less than plasma) • cl 109 (slightly more than plasma) . K 4 . Buffer lactate 28 • Ca 1,4 (slightly less than plasma) • ph 6-7,5 • Osm 273 (slightly less than plasma) Used for resus and replacement
State the composition (Na, Cl, k, buffer, ca, mg, glucose, pH, osmolality ) of plasmalyte B and uses
• Na 130 • cl 110 (slightly more than plasma) •K 4 . Buffer hco3 27-28 . Mg 1,5 (slighty more than plasma) • ph 7, 4 . Osm 273 Used for resuscitation and replacement
State the composition (Na, Cl, k, buffer, ca, mg, glucose, pH, osmolality ) of maintelyte 5%
• Na 35 (much less than plasma) • cl 65 (much less than plasma) • K 25 (much more) • mg 2,5 (slightly more than plasma) • Glucose 50 g (much more ) • Ph 4 (much less) • Osm 405 ( much more) Used for maintenance
What are normal daily water, electrolyte, proteins and glucose requirements?
Water 30-50 ml /kg/day
Na, cl, k 1 mmol/kg/day
50-100 g/day glucose (about 2000 cal)
Proteins 1,5 g/kg per day ( 2g needed in hypercatabolic patients)
When should maintenance fluids be prescribed and which is the preferred fluid and dose?
When patient can’t meet daily water and caloric needs orally but doesn’t have any added loses or excesses
Maintelyte 5% 60-80 ml per hour
Consequences of gastric fluid loses eg aspirate, fistula, vomiting?
Hypochloraemic metabolic alkalosis
Low Na, cl, K
High hco3
Consequences of fluid loses by pancreatic fistula?
Hyponatraemic hypokalaemia metabolic acidosis
Low na, k, hco3
Normal cl
Consequences of fluid loses by small bowel enterocutaneous fistula?
Hyponatraemic hypokalemic metabolic acidosis
Low na, cl, k, hc03
Consequences of fluid loses by biliary fistula?
Alkalosis may occur
Low na, cl, K
Normal hco3
Acid-base Consequences of fluid loses by diarrhoea?
Hyperchloraemic metabolic acidosis ( non anion gap)
High na, cl, hco3
Low K
What is the common protocol for fluid replacement?
• Quantify 6 hourly water loses then replace using nacl containing crystalloids (ringers, plasmalyte B) to admin equal volume = 1:1. formula
Eg ECF loosing 450ml every 6 hours, then add 450 ml ringers to maintenance every 6 hours to keep water balance.
How often should electrolytes and CMP be monitored when practicing fluid maintenance?
Daily
Blood products ratio used?
4 RCC: 4 FFP: 1 mu platelets
Which induction agents use for trauma patients?
Etomidate or ketamine
Which maintenance anaesthetic agents use for trauma patients?
Ketamine
