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Hemorrage q

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virgola82
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05/10/07 - 03:11 PM

A 45 yo male patient arrives at the ER because his arterial blood pressure has fallen below 40 mmHg as a result of a severe blood loss. Which of the following is primarily responsible for maintaining peripheral resistance and blood pressure in this patient?

A. Arterial baroceptors

B. Central chemoreceptors

C. Stretch receptors in the right atrium

D. Peripheral chemoreceptors

E. Stretch receptors in the left atrium

Edited by virgola82 on 05/10/07 - 04:42 PM

arlete
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05/10/07 - 04:14 PM

A

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al-fateh
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05/10/07 - 04:22 PM

new_n_lost
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05/10/07 - 04:33 PM

A. Arterial baroceptors

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virgola82
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05/10/07 - 04:40 PM

Are you sure? I said it too....

virgola82
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05/10/07 - 05:01 PM

little hint: look at the BP

Luckyall
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05/10/07 - 05:38 PM

is the strech REC in Right Atrium for sure

Luckyall
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05/10/07 - 05:41 PM

The stimuli arising from strech REC act to chronically inhibit ADH secretion. The decr in blood Vol---> causes venous& arterial REC to send fewer signals to CNS --> decreasing the chronic inhibition of ADH secr. This is the BIG TIME very imp mech in restoring ECF following hemorrhage wink

virgola82
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05/11/07 - 07:20 AM

ECF volume is determine by total body sodium which in turn is controlled by aldosterone; osmolality is determined by plasma sodium conc that is controlled by ADH which is in turn regulated by ATII and stretch receptors.

Tricky q

new_n_lost
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05/11/07 - 07:46 AM

#10

but i think the answer shud be Peripheral Chemoreceptors cos the Arterial Baroreceptors stop working when the BP goes down below 70mmHg they stop working so its the Chemoreceptors which take over can u plz post the Explanation.

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new_n_lost
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05/11/07 - 08:18 AM

#11

virgola82 wrote:
ECF volume is determine by total body sodium which in turn is controlled by aldosterone; osmolality is determined by plasma sodium conc that is controlled by ADH which is in turn regulated by ATII and stretch receptors. <<<<

Tricky q

R U SURE Abt this Cos I wud really like to know the Source thanks Yes indeed a tricky question

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new_n_lost
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05/11/07 - 08:19 AM

#12

ADH by Stretch Receptors i know but also by Ang II that is wht i m not getting.

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new_n_lost
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05/11/07 - 08:34 AM

#13

Ok Found it Thanks

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GoodGirl
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05/11/07 - 08:53 AM

#14

Where did you found it ? I mean, where can I read about it ? Please, NNL .

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silver
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05/11/07 - 08:56 AM

#15

Ganong, p. 245

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virgola82
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05/11/07 - 02:17 PM

#16

OK, the right answer is D: peripheral chemoreceptors. This is the explanation:

When the mean arterial BP falls below 40 mmHg (this is what it says here: 40, not 70... anyway I'll doublecheck), the arterial baroreceptors are completely unloaded and baroreceptor inhibition of sympathetic centers ceases. Therefore, the periferal chemoreceptors become the main source of additional sympathetic drive to the arterioles and primarily responsible for maintenance of mean arterial BP.

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