Thank you to everyone who commented and voted on this case - some great debates!
Before I go through assessment of fluid responsiveness in critical care, it's worth saying that it is one component of your overall assessment of the patient. Not to be taken in isolation. [1/12]
One of the key principles here is that the positive pressure delivered into the thorax from the ventilator will affect the venous return to the right heart (with less returning during inspiration).
This leads to variation in IVC and LVOT VTI/V max values.
[2/12]
Some variation is completely normal.
But when patients are hypovolaemic, they are more susceptible to the pressure changes, & the variation will get larger.
In ICU we can also see this as "swing" on an arterial line trace
It is not so simple in a spont breathing patient
[3/12]
In this case, the IVC variation & LVOT VTI variation were within normal limits:
The middle ground is not clear one way or other.
[4/12]
The other principle here is about the Frank-Starling curve.
In summary, this says that increasing the pre-load (LVEDV), will increase the stroke volume, up to a point. At that point, further increases will have no affect on SV, and may worsen SV.
[5/12]
To assess this we can compare the LVOT VTIs before and after a fluid bolus, or a passive leg raise (PLR).
Using a PLR we deliver a fluid bolus to the patient from their lower limb venous pool - essentially sparing them a fluid bolus if they turn out to be non-responsive.
[6/12]
In this case, the response was negligible.
The normal values are:
Increase of <8% - not fluid responsive
>12% - fluid responsive.
With a zone of uncertainty in between
As with IVC and LVOT VTI, there will be a few exceptions where values can be misleading.
[7/12]
So in this case:
- Minimal IVC variation
- Minimal LVOT VTI variation
- No response to a PLR.
We can confidently say he is currently unlikely to be fluid responsive (remember in critical care the patient can change very rapidly).
[8/12].
The other thing I always try to comment on is any signs of volume overload, to try and help give as much useful info as possible:
- Is the patient unlikely to be fluid responsive and look about right?
- Is the patient unlikely to be fluid responsive and look overloaded?
[9/12]
I didn't show you all the the images here, but can tell you:
- The RV has normal dimensions with normal TAPSE and fractional area change.
- The RA is normal size
- The IVS has normal movement, with no bowing into LV.
In essence, no signs of volume overload.
[10/12]
In summary, this patient is unlikely to be fluid responsive, and has no signs of volume overload.
I attach a helpful diagram I use as my prompt for these scenarios.
It's taken from a book I use, but have no conflict of interest with.
[11/12]
I hope this has been useful. As always, do let me know your thoughts, and if you agree/disagree with my interpretation.
A patient with long-standing renal failure has a cardiac arrest on commencement of dialysis. You achieve ROSC, and do a focused echo. Here are the views you achieve.
Parasternal long axis...
This is my first critical care echo case tweetorial. I will be discussing the assessment of potential fluid responsiveness in critical care. Case today, answers tomorrow.
Please do give me honest feedback so I can make these useful.
The case is a post-op patient who is hypotensive. They have had some fluid resuscitation already. Do they need more filling? Do they need inotropes? Do they need vasopressors?
1. A person has mild Covid infection and isolates at home for 10 days. They go back to work and are fine. A week later they are killed crossing the road.
This IS counted as a death from Coronavirus.
[2/4]
2. A person has severe Covid infection and spends over a month in ITU. They get weaker, and get other chest infections, while in hospital. Ultimately they fail to recover and die.
This is NOT counted as a death caused by Coronavirus.
[3/4]
As lockdown restrictions are being lifted, it’s tempting to think that life can start to get back to normal. I think it’s key to understand how hospitals have changed to cope with COVID-19 and how rushing to normality is causing much apprehension for the many health workers [1/8]
Even before the #COVIDー19 pandemic, ITUs were typically short staffed and running at almost full capacity.
This relied on all medical team members working incredibly hard together, along with goodwill overtime, to ensure safe staffing levels. [2/8]
To cope with the surge in #COVIDー19 cases, hospitals cancelled most elective operations.
This led to more beds being available, and medical and nursing staff were redeployed in order to provide care for the sickest people in our new expanded intensive care areas. [3/8]
Organ donation in the UK has now changed to an "Opt-out" system.
What does this mean for you and your family?
Bear with me, and I will briefly go through the changes, and how you can ensure you can communicate your wishes, even if it is too hard to talk to your family. [1/n]
Death and dying are very hard subjects to talk about, and often make people feel uncomfortable. However, at some stage we will all die, and it’s worth thinking in advance what we would want at that point in our lives - and ideally communicating that to those close to us. [2/n]
Sometimes, death may occur in a way that means the body organs (e.g. kidneys, lungs) would not be significantly injured, and could potentially be donated to someone else who might really benefit. [3/n]
With more people being offered testing for Coronavirus, daily updates on numbers tested, and potential news in the bid for an accurate antibody test, it’s a good time for an overview on testing. A thread. [1/n]
There are two broad types of test:
1. Those looking for antigen (i.e. you currently have Covid) 2. Those looking for antibodies (i.e. your immune system has faced Covid recently). [2/n]
Antigen tests need a respiratory sample, the vast majority of which are nasopharyngeal or oropharyngeal swabs (or both). This means a sample taken from far back in your nose or mouth.