Perioperative Fluid and Blood Management Quiz

abnormal skin turgor, dehydrated mucous membranes, thready peripheral pulses, increased resting HR, BP changes from supine to sitting or standing (orthostatic changes), decreased urinary flow rate

pretibial pitting edema in the ambulatory patient, presacral pitting edema in the bedridden patient, late signs of hypervolemia: CHF, tachycardia, tachypnea, elevated jugular pulse pressure, pulmonary crackles, wheezing, cyanosis, pink and frothy pulmonary secretions

rising hematocrit and hemoglobin, progressive metabolic acidosis (including lactic acidosis), urine specific gravity > 1

serial hematocrit, arterial blood pH, urine specific gravity or osmolality, urine serum sodium or chloride concentration, serum sodium, BUN-to-creatinine ratio

may be altered by perioperative factors

rising hematocrit and hemoglobin, progressive metabolic acidosis (including lactic acidosis), urine specific gravity > 1

The three functions of crossmatching in blood transfusion are to confirm ABO and Rh typing, to detect antibodies to other blood group systems, and to detect antibodies in low titers or those that do not agglutinate easily.

Some complications of massive blood transfusion include coagulopathy (dilutional thrombocytopenia, lack of factors 5 & 8, DIC), and metabolic problems (hyperkalemia, citrate toxicity, acidosis, hypothermia, impaired O2 carrying capacity due to reduced 2,3 DPG concentration).

Transfusing one unit of PRBCs will increase the hematocrit by 2-3% or 1 g/dL of Hgb in an average adult.

The clinical manifestations of a hemolytic blood transfusion reaction include fever, chills, chest/flank/back pain, nausea, oliguria or anuria, hemoglobinuria, diffuse bleeding, and indicators of decreased temperature, blood pressure, and urine output if the patient is asleep.

The alternatives to homologous blood transfusion include autologous transfusion, perioperative blood salvage (CellSaver), intraoperative hemodilution, and the use of substitute products.

The indications for Fresh Frozen Plasma (FFP) administration include treatment of isolated factor deficiencies, reversal of warfarin, and correction of coagulopathy associated with liver disease. 1 unit of FFP increases the level of clotting by 2-3% in adults.

PAOP measurements help determine a patient's volume status. A PAOP < 8 mmHg indicates hypovolemia in patients with normal LV compliance, while PAOP < 15 mmHg indicates relative hypovolemia in patients with impaired LV compliance.

Echocardiography is more accurate at determining cardiac filling pressures than PA pressure measurements.

During spontaneous ventilation, blood pressure decreases on inspiration, while during positive pressure ventilation, it increases on inspiration.

Crystalloid solutions rapidly equilibrate with and distribute throughout the entire extracellular fluid space, while colloid solutions help maintain plasma colloid oncotic pressure and mostly remain intravascular.

The intravascular half-life of crystalloid solutions is 20-30 minutes, while for colloid solutions, it is 3-6 hours.

Colloids are indicated for fluid resuscitation in severe intravascular fluid deficits (e.g., hemorrhagic shock) prior to the arrival of blood for transfusion.

The determinants of perioperative fluid requirements include basal requirements, preoperative deficits, blood loss, third space losses, evaporation losses, transcellular fluid losses, effects of anesthesia, and urine output.

Normal hemoglobin (Hgb) levels are 14-18 g/dl for males and 12-16 g/dl for females.

Physiologic adaptations to acute normovolemic anemia during surgery include increased cardiac output, redistribution of blood to oxygen-dependent tissues, and increased oxygen extraction.

An acceptable minimum preoperative hematocrit for healthy patients is 18%, while patients with symptomatic cardiac disease should have a preoperative hematocrit of 30%.

Red cell products available include red blood cells, deglycerolized red blood cells, leukocyte-reduced red blood cells, washed red blood cells, and whole blood.

The difference between a type and screen and a crossmatch is that the former identifies the patient's blood type and screens for antibodies, while the latter tests compatibility between donor and recipient blood.

Potential dangers include pulmonary edema, acidosis, and hindered healing due to the increased interstitial fluid.

Fluid requirements are determined by preoperative loss replacement, maintenance fluid replacement, surgical loss replacement, and blood loss replacement.

The daily fluid requirement is calculated based on a 4-2-1 rule and adjusted for metabolic rate.

Goal-directed fluid therapy utilizes stroke volume and cardiac output to guide fluid administration in perioperative fluid management.

Balanced salt solution is the preferred initial resuscitation fluid, distributing quickly into both blood volume and interstitial fluid.

Third-space losses refer to unexplained fluid requirements, necessitating further infusions to maintain intravascular volume and adequate perfusion.