Crystalloid
Normal Saline
Isotonic solution of sodium chloride in water
Simplest fluid replacement, normals saline can be given in a large bolus for rapid fluid resuscitation or as a maintenance fluid. There is a risk of hyperchloræmic acidosis from the high chloride concentration in NS. NS is also used as a vehicle in transfusion of blood products.
CSL/Hartmann’s (Ringer’s Lactate)
Isotonic solution of sodium chloride, sodium lactate, potassium chloride, and calcium chloride in water
CSL has electrolyte concentrations more similar to plasma and may be a better alternative to NS. The presence of calcium in the solution may cause precipitation of some compounds.
CSL has an alkalinising effect due to the presence of lactate. Also due to its lactate content it should not be used in patient with lactic acidosis, not because it affects disease course but rather because it confuses the gas machine.
Both NS and CSL may produce hypernatraemia when used as a sole maintenance fluid as they provide no free water.
D4/5NS1/5 Dextrose in Normal Saline
Isotonic solution of dextrose (4%) and sodium chloride (0.18%) in water. Dextrose/saline becomes hypotonic in vivo as the sugar is taken up by cells.
Dex Saline is often the maintenance fluid of choice as it provides both electrolytes and free water, and better replaces obligatory fluid losses (both sensible and insensible). The addition of glucose may also help prevent catabolism in anorexic patients.
Optimal maintenance would be ‘four and a fifth’ with potassium to cover the daily potassium requirement (1mmol/kg/day).
D5W Dextrose in Water
Isotonic solution of dextrose in water. Plain dextrose becomes hypotonic in vivo as the sugar is take up by cells
Dextrose containing solutions cause an increase in insulin secretion which drives potassium into the cell and can precipitate hypokalaemia
Colloid
Albumin
Human albumin is best left to those people that know what they are doing. What you should know is that it rather good at maintaining intravascular volume, at least for a while in most patients.
Artificial colloid
This come from cows usually, perhaps one for the expert experts…
Blood products
Blood products should be crossmatched before administration.
pRBC / Packed Red Cells
Packed red cells are often administered in suspension and are indicated in significant blood loss and/or anaemia where hæmoglobin falls below 90g/L.
As a rule of thumb, one unit of pRBCs will raise the hæmaglobin by 10g/L.
PLT / Platelets
Concentrated platelets can be prepared by apheresis or pooled donation (from whole blood or platelet-rich plasma).
Platelets have a nucleus independent “apoptotic clock” that runs out at ~10 days and labels the cell for destruction. This explains the shelf life of 4-7 days.
Indication for platelet transfusion according to NICE:
Active bleeding with PLT count <30, or severe/critical site bleeding with PLT count up to 100
Prophylaxis of bleeding with PLT count <10, or PLT count <50 in patients soon to undergo invasive procedure or surgery.
And some others… of note, in HELLP syndrome consider transfusion when PLT count <75, aiming PLT count >50 (RCOG)
FFP / Fresh Frozen Plasma
The fluid component of a unit of whole blood, containing all coagulation factors except platelets.
It is indicated for correction of deficiency of coagulation factors in active bleeding. It is also indicated for a planned surgery or invasive procedure in the presence of abnormal coagulation tests, reversal of warfarin in active bleeding, or planned procedure when vitamin K is inadequate to reverse the warfarin effect, thrombotic thrombocytopenic purpura, and congenital or acquired factor deficiency with no alternative therapy.
FFP is stored at -30 Celsius. Before administration, it is thawed to near body temperature and should be administered immediately after thawing.
Cryoprecipitate
Fresh frozen plasma is thawed to between 1-6ºC before centrifugation, the resulting precipitate is then collected.
Cryoprecipitate contains mostly fibrinogen (≥140mg/unit) and factor VIII (≥70IU/unit), as well as von Willebrand factor (>100IU/unit). Preparation from whole blood or plasma aphaeresis yields different compositions.
Indications for use are essentially limited to maintenance therapy of hypofibrinogenaemia and management of haemophilia, von Willebrand’s disease or Factor XIII deficiency (where one is unable to get a hold of the specific factor concentrate.
Prothrombinex
Prothrombinex is lyophilised human clotting factor concentrate prepared by adsorption of coagulation factors from plasma followed by selective elution.
The only routine indication is reversal of warfarin. It does not, in fact, reverse warfarin; it merely replaces the inactive factors.