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* please explain these questions
  dexa - 12/31/18 01:56
  hi guys, please explain this questions.

1. why pyridoxine in hyperemesis gravidarum ? what s mechanism of action?

2. Why during pregnancy progesterone increases tidal volume and respiratory rate is unchanged ?

3. why in preterm pregnancy MgSO4 can be given with indomethacin but not with nifedipine?

4. what is the mechanism of oxytocin causing hypotension ?

5. why anemia in fetus causes sinusoidal heart rate instead of tachycardia?

6. WHy HPV vaccine in c/i during pregnancy even though it is not a live vaccine?

Please shed some light on these questions.

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* Re:please explain these questions
  dexa - 12/31/18 16:41
  ok guys, no one wants to answer.

for question 3

3. why no MgSO4 with nifedipine ?
- when given with MgSO4, nifedipine can suppress muscular contractility and cause respiratory depression

Happy New Year to you guys!
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* Re:please explain these questions
  cardio69 - 12/31/18 17:26
  You understand for 1st management you can B6 &/or ginger, then 2nd line you add doxylamine and 3rd line adm antimemetic… now that depends how bad would be you may have to rehydrate pat via IV and supply with electrolytes & ondansetron and if that not going get you anywhere -> then glucocorticoids probably...

-Regard to you Q here not really clear but B6 probably have intrinsic antinausea properties &/or synergy with the antinausea prop of antihistamines, but I don’t think concrete proven correlation btw maternal B6 and indicine or severity of nausea. Thats all I think you need to know...
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* Re:please explain these questions
  cardio69 - 12/31/18 17:27
  2ndry to the ↑ min ventilation* 2nry to level progesterone & ↑ metabolic rate of both the mom & kido ( other word Prog tickle the respiratory center -> physiological, chronic comp RA => ↑ TV/~40% -> *) also ↓PCO2 like 30… the inc vent is more than the corresponding elevation O2 consumed ~20%
Let me make it more clear progesterone as I said INC min volume (amount inhaled in & out of lung in one min) by 40% in 1st tri by inc TV ONLY,

Q4U) What you think gone happen to diaphragm?
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* Re:please explain these questions
  cardio69 - 12/31/18 17:46

What effect progesterone have on smooth muscle in the airway?
Oxy very close to what similarity to what hormone syn/peptide you know of?
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* Re:please explain these questions
  dexa - 12/31/18 21:40
  Hi cardio69
thanks a lot.

I think diaphragm is gonna be pushed up by the uterus..and progesterone also has muscle relax. effect.

Oxytocin very close to ADH I think, causing hyponatremia? but hypotension? please explain this one .
thanks cardio
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* Re:please explain these questions
  cardio69 - 01/02/19 16:43
  Hello:) Most welcome.
Rt on your first point but on your 2nd point more or less similar to Vasopressin -> hypertension. Oxytocin Rs ergometrine not completely understood but perhaps via partial agonist @ alpha adrenoRs or 5-HT (besides 1ry action of Oxy tickling SM contraction -> childbirth, just as adding to your knowledge uterine effect of oxy due in part to INC production & release of the PGF2a from myometrium/ and little decidua😊
Anyhow, synthetic one that im guessing you talking about/Pitocin -> hypotension which you should give it SLOW ( 40U @ least 500cc cry over 10min) ideally, bz it shown to bring down MAP ~40% & SVR ~60% but not on that 10 min I just preach here… hope that clear it for you in real practice. So bz of that vascular SM relaxes you ever never give as undiluted bolus dose bz of that hypOTN/arrhythmias can develop.

Safety of HPV vac is pregnant is limited. Although not recommended during pregnancy but some case u see inadvertently vaccinated ( unplanned or unrecognized pregnancies) > Moreover if I recall correctly Denmark ( did regisor base cohort study ˝ mil pregnancies 06 to I guess end of 2013 investigated the assoc btw quadrivalent HPV during preg & adverse preg outcomes -> they include major birth defect/low b weg/ small size gestational age/spontaneous abo/preterm birth and I think stillbirth… and later propensity score match analytics said a different thing. Whatever the case maybe, FOR YOUR prep & real practice😊 with all my preach evidence may suggest is safe, just know IS NOT RECOMMENDED😊
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* Re:please explain these questions
  cardio69 - 01/02/19 16:44
  Happy new year!!!
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* Re:please explain these questions
  dexa - 01/03/19 14:10
  @cardio69, man you rock!
Thanks and Happy New Year.
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* Re:please explain these questions
  dexa - 01/05/19 21:07
  1. What is mechanism of macrocytic anemia in congenital hypothyroidism ?

2. indications for flexible and rigid bronchoscope?

3. In case of foreign body aspiration which are indications for flexible bronchoscopy ?

thanks in advance
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* Re:please explain these questions
  cardio69 - 01/06/19 20:22
  :) Thanx

Most probably due to defect EP action/or production + thyroxine in vitro need to start EP act on erythroid colony formation (+ ↓ tissue O2 requirement due to ↓ basal metabolic rate) -> hypothyroidism may by itself -> physiological adaptation -> ↓EP production/consequent dec EP & -> low reticulocyte count give fall on that for macro pic u see. Hope some1 give more light to it😊 all I could come up with.

That would be a long list you can google it… I really don’t think you need to know all. Indication for flex more for a routine exam, or use catheter & brush for cytology (i.e transbronchial lung) or localized bleeding in cases of hemoptysis. Rigid more of preventing hyperextension of neck let say with pat in aortic aneurysm (read more below)

If your pat about to parish forgets about imaging go straight -> intervention;). Now if you adult pat suspect of FNA & “STABLE” -> PE-> X-ray ( or CT if your x, not unconvincing) -> flex broncho (both dx & therapeutic) & can confirm it & you can attempt to remove it. Now if you pat cervicalfacial trauma/or mech vent; Rigid broncho use rather than a diagnostic tool. Also, more preferred in kido due wider instrument lumen & vent & easier to remove it)
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