0521779407-19 CUNY1086/Karliner 0 521 77940 7 June 4, 2007 21:21
1340 Shock
➣Lactate Level >2 mEq/L
Most accurate marker of shock; consider empiric therapy if
laboratory turnaround >1 hr
■Advanced Studies:
➣A-VDO 2 >5 ml/dl
requires PA catheter; may be normal in sepsis
Mixed Venous O 2 <70%
➣requires PA catheter; may be normal in sepsis
■Urine:
➣Fractional Excretion Sodium <1%
➣(UNa×PCr)/(UCr×PNa)×^100
➣Urine Sodium <20 mEq/ml (hypovolemia)
■Other Tests:
➣ECG – signs of ischemia, MI
➣Cardiac Output – PA catheter, Echocardiography
differential diagnosis
Hypovolemic vs Cardiogenic
■Hypovolemia: Low PCWP, inadequate RA or LV filling on echocar-
diography
■Cardiogenic: ECG changes, hypodynamic LV on echo, increased tro-
ponin, CPK, adequate PCWP
Septic vs Neurogenic
■Septic: Fever, leukocytosis, bacteremia, normal mixed venous O 2 ,
AVDO 2
■Neurogenic: Acute spinal trauma
management
What to Do First:
■Secure airway: Endotracheal intubation if mentally altered
■Institute respiratory support: bag-valve or mechanical ventilat-
ion
➣Caution: Positive pressure will exacerbate hypotension
➣Continuous monitoring with arterial catheter is recommended
■Augment preload: Fluid Challenge: 20 cc/kg crystalloid, 10 cc/kg
colloid
■Raise systemic perfusion pressure: Dopamine, phenylepherine,
epinepherine, norepinepherine
■Caution: Dobutamine may exacerbate hypotension