Critical Care / Medicine Flashcards
How do you estimate blood volume?
60cc / kg
Blood volume is approximately half of body weight in a normal adult
Classification for blood loss
Class I - EBL <750, BP and P and UOP nl
Class II - EBL 750-1500, UOP decreased, HR elevated, BP nl
Class III - EBL >1500, BP dropping, oliguria
Class IV - loss of vital signs, no urine output
Types of shock
Hemorrhagic
Septic/Distributive
Obstructive
Cardiogenic
Septic shock
Low systemic vascular resistance
High cardiac output
Low wedge pressure
Hemorrhagic shock
High systemic vascular resistance
Normal cardiac output
Low wedge pressure
Cardiogenic shock
High systemic vascular volume
Low cardiac output
High wedge pressure
What clotting factors are in FFP?
FFP provides factors II, V, VIII, IX, X, XI, and antithrombin III and fibrinogen (lower concentration than cryo)
What clotting factors are in cryoprecipitate?
fibrinogen (higher concentration), von Willebrand factor, factor VIII, factor XIII
What is the massive transfusion protocol in OB?
1:1:6 - pRBC : plasma : platelets
(different in every hospital, may be 1:1:1 or 1:1:2)
What is the goal level for fibrinogen in a hemorrhage?
> 100 or >150
What electrolyte abnormalities can occur with massive transfusions?
HypoCa
Hyper K
Due to citrate in pRBC
When to transfuse platelets?
<50 in massive bleeding
<10 for prophylaxis
<20 for procedures
What is the definition of massive transfusion?
> 6u within 2 hours
replacement of >50% of blood volumes
10U within 24h
what are adverse effects of massive transfusions?
Volume overload
HypoCa
HyperK
HypoMag
Hypothermia
Metabolic alkalosis (citrate)
DIC
What is the fluid resuscitation for septic shock?
30 cc/kg/hr
What is the goal for antibiotics administration in septic shock?
Broad spectrum antibiotics in <1hr
Blood cultures prior to antibiotics
Virchow triad
Venous stasis
Endothelial injury
Hypercoagulability
Risk factors for PE
What most affects nutritional status?
Weight > age > height
Definition of malnutrition
albumin <3.4
loss of 15% of usual body weight
What is the threshold for increased risk of low albumin?
Albumin <3
Associated with poor surgical outcomes, operative complications
What is the mean survival after diagnosis after malignant bowel obstruction?
With TPN = 72days
Without TPN = 41days
TPN may buy about a month of time. No meaningful survival benefit.
TPN complications
Infection
Cholestasis
Refeeding Syndrome
Overfeeding
Electrolyte abnormalities
Pneumothorax (with placement of line)
Short bowel syndrome
<100-150cm of functional small bowel
Assoc with malabsorption, diarrhea, metabolic abnormalities, B12/fat soluble vitamin deficiencies
Caused by surgical resection AND radiation bowel injury
Refeeding syndrome
Features:
- HypoPhos
- HypoK
- congestive heart failure
- peripheral edema
- hemolysis
- seizures
Due to aggressive nutrition replacement leading to fluid shifts/electrolyte imbalance
Features of pre-renal etiology
FENA <1%
Ur/Pr Creat >20:1
BUN/Cr >20:1
UNa <10
Uosm >500
Causes of Afib
Hypoxia
PE
Volume overload
Volume depletion
A-fib with RVR treatment
Beta-blocker (first line)
Diltiazem/amiodarone (second line, call cards)
Hypertensive urgency
Systolic >160
Diastolic >100
Asymptomatic
Hypertensive emergency
Systolic >180
Diastolic >120
+ active endo-organ damage (encephalopathy, pulmonary edema, aortic dissection)
Need IV tx (nitroprusside, nitroglycerin; also nicardipine, labetalol, esmolol, hydralazine)
At risk for rebound hypoperfusion leading to stroke, MI, and blindness
What antibiotics most commonly contribute to C diff?
Cipro
PCN
Cephalosporin
Neutropenic Fever
T>38.3 x1
T >38.0 sustained over one hour
May be limited by chronic steroid use, elderly age (may be hypothermic)
ANC <1500
Risks of neutropenia
ANC < 1500 = moderate risk
ANC < 500 = severe infection risk
ANC < 100 x3 weeks = 100% infection risk
Tx of neutropenic fever inpatient
Zosyn or Cefepime
Tx of neutropenic fever outpatient
Augmentin + Cipro
What are the advantages of LMWH (lovenox) over unfractionated heparin?
More predictable therapeutic response
Longer half life
Lower risk of HIT
Less bone mineral density loss
What’s the increase in cardiac output in pregnancy?
45%
What’s the cardiac output changes postpartum?
60-80% increase immediately postpartum
then rapid decrease
What is the change in HR in pregnancy?
20% increase
