the cvp in hypovolemic shock
DESCRIPTION
The CVP in patient with hypovolemic shock case : Mostafa 22years old Agitated and compleaning of abdominal pain Airway is patent Respiratory rate 32 per min. BP 90/60 mmHg. Pulse 130 bpm. Temp 36C. Abdominal distension. Cold skin Nsogastric tube rvealed green liqued Urinary cathetar revealed dark urine Hemoglobin is 7. FAST is postive.TRANSCRIPT
Hwmo
Maryam AL-Qahtani.
G:3
Clinical vignette 2
Shock
Objectives:
What would be the central venous and/or
pulmonary capillary occlusion pressure
(Low, normal, high )?
Hemorrhagic shock is a condition of reduced tissue perfusion,
resulting in the inadequate delivery of oxygen
and nutrients that are necessary for cellular
function.
Venous pressure:is a term that represents the average blood pressure within the venous compartment.
Central venous pressure:considered a direct measurement of the blood pressure in the right atrium and vena cava.
Central venous
pressure
Normal
value :CVP is 2-6 mm Hg.
ΔCVP = ΔV / Cv
change in volume (ΔV)The compliance (Cv)
Equation:
Factors influencing the Central Venous Pressure:
Cardiac output.
Blood volume.
Venous constriction.
Changing from standing
to supine body posture.
Arterial dilation.
CVP is elevated by :Heart failure or PA stenosis which limit venous
outflow and lead to venous congestion.
CVP decreases with:Hypovolemic shock from hemorrhage, fluid shift,
dehydration.
Pulmonary capillary occlusion pressure:
intravascular pressure as measured by a catheter
wedged into the small pulmonary artery ; used to
measure indirectly the mean left atrial pressure.
Normally about 8-10 mmHg.
In our case :What would be the central venous and/or pulmonary capillary occlusion
pressure (Low, normal, high )?
Early stage of shock .Compensate stage
The central venous pressure
and pulmonary capillary
occlusion pressure ……
Due to the compensatory
mechanism
Systemic arterial blood pressure
Blood volume venous return volume
the central venous pressurepulmonary arteries blood flow
Initial stage: CVP slightly decrease
Compensatory stage:
1/ increasing stroke volume.
2/ increasing the heart rate.
3/raising blood pressure.
4/increasing the rate of return of venous
blood to the heart.
Vasoconstriction blood
vessels + increase blood
volume …..>increase
arterial pressure.
CVP Normal
•Hemorrhage decreases blood volume and decreases CVP (A→B)
•By compensatory mechanism (B→C),which increases CVP andshifts blood volume toward heart…..> increase pulmonary capillary occlusion pressure
In Short:
The CVP & PCWP in hypovolemic shock differs
depend on the stage of the shock.
Initial stage decrease
Compensatory stage normal
Uncompensatory stage decrease
Guyton & Hall. Text book of Medical physiology .
.Merck Manual.
.Up to data. Website
http://www.rnceus.com/hemo/cvp.htm
http://www.medscape.com/viewarticle/749208_7
http://cvphysiology.com/Blood%20Pressure/BP020.htm