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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Which among the following is best method to assess intake of fluid in Polytrauma pt -
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The correct answer is  • Lets see each option one by one
Urine output

"Urine output is a quantitative and relatively reliable indicator of organ perfusion. Adequate urine output is 0.5 ml/kg/ h in an adult, lml/kg/h in a child and 2ml/kg/h in an infant less than 1yr. of age."

Pulse-

"Although tachycardia may be the earliest sign of hypovolemia, individuals in good physical condition, and particularly trained atheletes with a low resting pulse rate, may manifest only a relative tachycardia, pts on blocking medication may not be able to increase their heart rate. In children, bradycardia or relative bradycardia can occur with severe blood loss. Conversely, hypoxia, pain, apprehension and stimulant drugs  produce a tachycardia"

B.P. -

Hypotension is not a reliable early sign of hypovolemia. in healthy pts.
Blood volume must decrease by 30 to 40 percent before hypotension occurs.
Younger pts with good sympathetic tone can maintain systemic blood pressure with severe intravascular deficit untill they are on the verge of cardiac arrest.

CVP

CVP measurement helps in distinguishing b/w cardiogenic shock and hypovolemic shock.
'A central venous catheter can give information about the relationship b/w intravascular volume and right ventricular function but should not be used to assess either factor independently." - Schwartz pretest based on 7/e.