Anesthesiologists are involved: Anesthesiologists are involved

Occult hypoperfusion syndrome

• Occult hypoperfusion syndrome

• is common in postoperative trauma patients, particularly young ones

• normal BP maintained by intense systemic vasoconstriction

• intravascular volume is low

• cardiac output is low

• and organ system ischemia persists.

• Such patients are at high risk for MOSF if hypoperfusion is not promptly corrected.

Technique shorcomings

• Technique shorcomings

• Vital signs Will not indicate occult hypoperfusion

• Urine output confounded by intoxication, diuretic renal injury

• Systemic acid-base status Confounded by respiratory status

• Lactate clearance Requires time to obtain laboratory result

• Cardiac output pulmonary artery catheter or use of noninvasive technology

• Mixed venous oxygenation Difficult to obtain, but a very accurate marker

• Gastric tonometry Requires time to equilibrate, subject to artifact

• Tissue oxygenation Emerging technology, appears beneficial

• Stroke volume variation Emerging technology, requires an arterial line

• Acoustic blood flow Investigational technology, unproven

• 100

• Invasive monitoring change to noninvasive approaches that assess of adequate metabolism,respiration, and oxygen transport in peripheral tissue beds.

• One minimally invasive technique is tissue oxygen monitoring (skin, subcutaneous tissue, or skeletal muscle).

• Skeletal muscle blood flow decreases early in the course of shock and is restored late during resuscitation, thus making the skeletal partial pressure of oxygen a sensitive indicator of low flow.

• Early goal directed treatment of septic shock ,with an emphasis on measurement of mixed venous oxygen saturation ,has influenced the care of trauma patient ,and many of ICUs are now using continiucely measured venous oxygenation to guide resuscitation.

• Stroke volume variation Change in arterial pressure driven by the respiratory cycle(during positive pressure ventilation) a reliable predictor of decrease intravascular volume.

Tissue hypercapnia

• Tissue hypercapnia

• has been suggested as a universal indicator of critically reduced perfusion

• measurement of *gastric mucosa Pco2 through gastric tonometry has been used in trauma patients as an indicator of restoration of splanchic blood flow, and **distal gut PH has shown promise as a reliable indicator.

• the most proximal area of the gastrointestinal tract, the ***sublingual mucosa, has been shown to be a useful site for measurement of Pco2

continuous

• continuous

• When sublingual Pco2(PsLco2) exceeded a threshold of 70 mm Hg (normal = 45.2 ± 0.7 mm Hg), its positive predictive value for the circulatory shock was 100%.

• Inadequate tissue perfusion as indicated by these specific monitoring or by the traditional systemic markers of serum lactate, base deficit, and decreased PH, must be treatment promptly once ongoing hemorrhaged is controlled.

• The rate at which a shock patient's lactate returns to the normal range is strongly correlated with outcome:

• failure to reach to normal range within 24 hours of a traumatic injury carries a greater of organ system failure and eventual death