Albumin/fluids and svr - page 2
by Zaphod 9,426 Views | 23 Comments
Ok, open heart RN's. Does Albumin increase SVR? Do isotonic solutions increase SVR? I was under the thinking that Albumin does, but was assured otherwise. Thank you guys and girls:)... Read More
- 0Dec 16, '10 by TakeBackSVR is only a calculated number
Resistance = Pressure Gradient / Flow
Any interventions that increase mean perfusion pressure (MAP - CVP) or decrease CO will mathematically increase the SVR number.
Giving fluid will have multiple effects- small inc in CVP, inc LV preload so inc CO at the same HR, barereceptor response to inc BP.... all these factors determine the ratio which will result in the SVR calcuation.
So in a mathematical sense, volume will inc SVR under certain circumstances. But at the bedside most folks use SVR to refer to drug mediated vascular tone. Post pump vasodilation is the most common cause, which is treated with pressors (neo/vaso/levo/dopa etc) as long as there is adequate preload.
- 0Jan 10, '11 by Esme12 Senior ModeratorQuote from RNbyDesignThank you.
My patient had very low SVR-so likely vasodilatated. I figured some albumin would bump the svr, but some people disagreed. Eventualy levo fixed the issue.
If the patient was vasodilated.....just adding fluid to try to fill a big pipe will not really work. YOu need to make the pipe smaller in volume so it takes less to fill it to the poper volume. Also albumin can cause diuresis further increasing the hypovolemia.
http://tinyurl.com/6ht3lso Here is a link to several good sites.....:heartbeat
- 0Sep 24, '11 by hl_dwt74Sure, vasodilation decreases SVR and there is an inverse relationship b/n CO and SVR. I would agree giving some Albumin but only if pt' Hct is only > 30 otherwise I would give 1 Unit of PRBC's. This pt. has gotten a dose of lasix in OR, could he be dry intravascularly may be? Norepi would be my first choice after volume expander is given prn.
- 0Sep 24, '11 by suannaHypovolemia causes a HIGH SVR- correcting the problem by adding fluid will reduce the SVR. Low cardiac output with high SVR is the hallmark of hypovolemia. Colloid corrects the problem for longer than crystaloid since the fluid dosen't 3rd space out as quickly. Low CO/CI with a normal or low SVR is an indication for a inotrope. High cardiac output with a low SVR and poor perfusion pressure is an indication for pressors. High SVR with elevated filling pressures is an indication for a vasodialator. If you drop someones SVR without adequate fluid volume they are going to crash or go tachycardic to compensate for the greater vascular space.
- 0Sep 25, '11 by TakeBackQuote from hl_dwt74-I've had one anesthesiologist give lasix in the OR but it is not common in my experience. BUT....every practice differs. Cardiac pts suck up volume so it would be an odd choice to diurese during that period.Sure, vasodilation decreases SVR and there is an inverse relationship b/n CO and SVR. I would agree giving some Albumin but only if pt' Hct is only > 30 otherwise I would give 1 Unit of PRBC's. This pt. has gotten a dose of lasix in OR, could he be dry intravascularly may be? Norepi would be my first choice after volume expander is given prn.
-Transfusing to a hct of 30 is a thing of the past. Cardiac pts as a whole can tolerate hgbs down to 7. In anemic pts who are not actively bleeding I use albumin for oncotic pressure. If bleeding or sig. anemic and shocky, then PRBCs.
- 0Feb 25, '13 by SRNA15Giving fluid will more than likely decrease your SVR even further because the vasculature dilates in response to increased volume within the system. The reason open heart patients "suck up volume" according to TakeBack is because opening the thoracic cavity completely eliminates the intrathoracic pressure which is generally around -4. This in and of itself significantly reduces the hearts ability to fill so you have to drastically increase the mean systemic filling pressure (above the normal value of 7 mm Hg) to compensate and maintain cardiac output.
- 0Feb 26, '13 by TakeBackThe main reason they require volume is due to the massive third spacing from cardiopulmonary bypass/inflammatory response, and the use of vasodilating agents for anesthesia and postoperative sedation. The thoracic pump mechanism you are suggesting would really only applies to the chest when it is open, during the case, not afterward.
- 0Feb 26, '13 by TakeBackIt is really difficult to say that volume loading will have any absolute effect on SVR. Resistance results from the interplay of flow (CO) and vascular tone. With fixed tone and CO the SVR would increase with IVF. However EVERY pt responds differently- the degree of change in the SV (ventricular compliance variability), vasodilation (vascular compliance variability) and HR response (chronotropic variability) makes it nearly impossible to predict. Experts on hemodynamics tend to agree that it is a bedside, case-by-case titration model which requires constant feedback to determine the individual results.