Hypovolemic- positional hypotension?

[LokiRN]

For a hypovolemic pt--Right Side Laying-( RSL ) the bp is 70/x. LSL the bp is 100/x... Why? Colleague say "classic sign" of hypovolemia but can give no mechanism. Is RSL restricting venous return by venacaval compression?
I am aware of LSL for pregnant pt to remove venacaval pressure but can find no literature re other pts inspite of mult. searches.
Can anyone suggest a site which details the pathophys?
Thanks, Loki

[Ricu]

For a hypovolemic pt--Right Side Laying-( RSL ) the bp is 70/x. LSL the bp is 100/x... Why? Colleague say "classic sign" of hypovolemia but can give no mechanism. Is RSL restricting venous return by venacaval compression?
I am aware of LSL for pregnant pt to remove venacaval pressure but can find no literature re other pts inspite of mult. searches.
Can anyone suggest a site which details the pathophys?
Thanks, Loki

Hi there,

I can't think of a specific website, text or a single disease entity which causes the symptoms you outline but there are countless conditions. Has this patient presented to the ED in this state? Has it happened before? The difference between right and left pressures while noteworthy is likely not related to the current issue and may not be significant especially if the pt. has known vascular disease. Which pressure seems to more accurately reflect the current state? Has there been an injury or loss of consciousness? Any other history? Other than hypotension, what does the rest of the exam show? What does the labwork show? ECG? Is there reason to suspect vena caval compression? Could it be sympathetic tone? Hemorrhage? Transient arrythmia? Excessive beta blockade? Digitalis toxicity? Other drugs? Drug interaction? It can certainly be a combination of the things listed or others not listed. Any reason not to try a fluid challenge? Obviously a complete work up needs to be done but often such conditions can be treated satisfactorily and the specific cause(s) will never be found.

R

[LokiRN]

Hello Ricu.

Pt transfered from floor w/ dx of uti/sepsis. Fluid bolus and pressors initiated prior to picc placement and xigris infusion. No significant past medical history.

My question relates to the comment of 2 co-workers who have stated that ANY pt w/ significant hypovolemia- whether relative (as here) or absolute- will display the RSL/LSL discrepancy. A "classic sign" they say yet neither can supply the mechanism of action.

Any anecdotal comments or other possible pathophys explainations?

Thanks, Loki.

[Ricu]

Hello Ricu.

Pt transfered from floor w/ dx of uti/sepsis. Fluid bolus and pressors initiated prior to picc placement and xigris infusion. No significant past medical history.

My question relates to the comment of 2 co-workers who have stated that ANY pt w/ significant hypovolemia- whether relative (as here) or absolute- will display the RSL/LSL discrepancy. A "classic sign" they say yet neither can supply the mechanism of action.

Any anecdotal comments or other possible pathophys explainations?

Thanks, Loki.

Hi Loki,

I've seen a lot of septic patients and while this right versus left discrepancy is common enough because of preexistent vascular disease, I have not seen this phenomenon as a "classic" presentation but maybe others have.

R

[SoldierNurse]

Hey Loki,

Check out the link below. Although, may not answer your posted questions directly... this is an excellent resource with related info for you.

Effects of Gravity on Venous Return

[bsn06]

Are these aline or cuff pressures? In addition to various conditions it could just be positioning- transducer lower than axis=higher pressure reading and vise versa, or it could be the patient lying on the bp cuff which in my limited experience will distort the reading.

[mrkmrrtt]

Hi there,

Too many ???? unanswered. Hx?, Labs?, Diagnostics? Ricu is right on, the BP gradient may not be significant in this case. Hypovolemic "classical" presentation I cannot say.

I do know preexisting vascular disease is common when R v L BP's > 20mm Hg are present, you stated "30". Carotid-Subclavian steal syndrome occurs only on the RS when there is RS Brachiocephalic occlusion, commonly presents asymptomatic. SSS Symptoms: dizziness, arm ischemia causing claudication. Physically: weak or absent Radial/Ulnar pulses in the presence of ipsilateral dec. blood flow when compared to contraleral BP readings suggest Steal Syndrome.

M