If someone has pulmonary conjestion,
and a swan-catheter is used to determine if the
conjestion is due to fluid overload, what value
of wedge pressure would determine that fluid overload
is the cause?
If the wedge pressure is high in someone who has
known kidney failure (creatinine = 2.5), and possible
heart failure, how can one determine which organ
is causing the problem?
Thank you very much for your help.
Marty Braff
Links
On 15 Nov 1996 19:32:57 GMT, br…@mtatm.mt.att.com (M.BRAFF()) wrote:
>If someone has pulmonary conjestion,
>and a swan-catheter is used to determine if the
>conjestion is due to fluid overload, what value
>of wedge pressure would determine that fluid overload
>is the cause?
>If the wedge pressure is high in someone who has
>known kidney failure (creatinine = 2.5), and possible
>heart failure, how can one determine which organ
>is causing the problem?
>Thank you very much for your help.
>Marty Braff
I would consider a wedge pressure of 18 or higher to suggest fluid
overload (the numbers are not very exact, however). To evaluate the
contribution the heart is making, one can measure cardiac output via a
thermodilution technique with the Swan, to see if the cardiac index is
significantly depressed, too. H2
Howard Homler <76212…@compuserve.com> wrote:
>I would consider a wedge pressure of 18 or higher to suggest fluid
>overload (the numbers are not very exact, however). To evaluate the
Would this vary at all with the age of the person. Would a higher
wedge pressure be expected in an older person?
>contribution the heart is making, one can measure cardiac output via a
>thermodilution technique with the Swan, to see if the cardiac index is
>significantly depressed, too. H2
What value of cardiac output would suggest that the heart is
the cause of the fluid overload?
Marty Braff
Don’t forget that the position of the sensor can be a cause of
abnormally high/low readings.
Other conditions which may affect the true wedge pressure are:
Poor measurement technique.
Thombosis in the Swan’s lumen.
Infusions running through the distal port.
Positive ventilation and high levels of PEEP.
Pulmonary artery stenosis.
Left ventricular hypertrophy.
On 27 Nov 1996 23:17:52 GMT, br…@mtatm.mt.att.com (M.BRAFF()) wrote:
- Hide quoted text — Show quoted text -
>Howard Homler <76212…@compuserve.com> wrote:
> Would this vary at all with the age of the person. Would a higher
> wedge pressure be expected in an older person?
>>contribution the heart is making, one can measure cardiac output via a
>>thermodilution technique with the Swan, to see if the cardiac index is
>>significantly depressed, too. H2
Paul Canning wrote:
> Don’t forget that the position of the sensor can be a cause of
> abnormally high/low readings.
> Other conditions which may affect the true wedge pressure are:
> Poor measurement technique.
> Thombosis in the Swan’s lumen.
> Infusions running through the distal port.
> Positive ventilation and high levels of PEEP.
> Pulmonary artery stenosis.
> Left ventricular hypertrophy.
With all these sources of errors does the swan catheter
help with differentiating a lung problem from a fluid
overload problem?
Marty Braff
- Hide quoted text — Show quoted text -
martin braff wrote:
> Paul Canning wrote:
> > Don’t forget that the position of the sensor can be a cause of
> > abnormally high/low readings.
> > Other conditions which may affect the true wedge pressure are:
> > Poor measurement technique.
> > Thombosis in the Swan’s lumen.
> > Infusions running through the distal port.
> > Positive ventilation and high levels of PEEP.
> > Pulmonary artery stenosis.
> > Left ventricular hypertrophy.
> With all these sources of errors does the swan catheter
> help with differentiating a lung problem from a fluid
> overload problem?
> Marty Braff
I can’t remember, offhand, the correct reference of a recent
article in one of the most read cardiology journals. That article
concluded that the S-G cath is not providing the information it should
while patients are put at *risk* (risk is small but it’s not
non-existant). In theory it should provide valuable information. In
practice however, is it used properly or when not really needed?
Guy
On Tue, 03 Dec 1996 09:29:06 GMT, paul.cann…@ukonline.co.uk (Paul
- Hide quoted text — Show quoted text -
Canning) wrote:
>Don’t forget that the position of the sensor can be a cause of
>abnormally high/low readings.
>Other conditions which may affect the true wedge pressure are:
>Poor measurement technique.
>Thombosis in the Swan’s lumen.
>Infusions running through the distal port.
>Positive ventilation and high levels of PEEP.
>Pulmonary artery stenosis.
>Left ventricular hypertrophy.
>On 27 Nov 1996 23:17:52 GMT, br…@mtatm.mt.att.com (M.BRAFF()) wrote:
>>Howard Homler <76212…@compuserve.com> wrote:
>> Would this vary at all with the age of the person. Would a higher
>> wedge pressure be expected in an older person?
>>>contribution the heart is making, one can measure cardiac output via a
>>>thermodilution technique with the Swan, to see if the cardiac index is
>>>significantly depressed, too. H2
So true. You know, there were some interesting issues raised about
Swans in JAMA a few months ago, saying that using a Swan was
associated with a higher mortality even in patients with similar
degrees of illness. Although everyone argues that "sicker patients
get the Swan" so one wonders if the groups were truly matched, I do
think that it’s not too difficult to get misled by all the factors
mentioned above. Hmmmm… H2
On Fri, 06 Dec 1996 23:17:38 -0500, martin braff
<mbr…@postoffice.worldnet.att.net> wrote:
Marty,
many of the mentioned errors are usually rule outable?? (is
that a word? probably not) Anyway, if you are careful and aware of the
potential for problems then the swan ganz can be used successfully.
As for determining heart as opposed to lung problems.
If the patient is in LVF, the wedge is high and pulmonary oedema is
cardiogenic.
If the heart functions normally, the wedge is normal, then pulmonary
oedema is due to increased capillary permeability. i.e. ARDS
- Hide quoted text — Show quoted text -
you wrote:
>With all these sources of errors does the swan catheter
>help with differentiating a lung problem from a fluid
>overload problem?
>Marty Braff
Paul Canning wrote:
> On Fri, 06 Dec 1996 23:17:38 -0500, martin braff
> <mbr…@postoffice.worldnet.att.net> wrote:
> Marty,
> many of the mentioned errors are usually rule outable?? (is
> that a word? probably not) Anyway, if you are careful and aware of the
> potential for problems then the swan ganz can be used successfully.
> As for determining heart as opposed to lung problems.
> If the patient is in LVF, the wedge is high and pulmonary oedema is
> cardiogenic.
> If the heart functions normally, the wedge is normal, then pulmonary
> oedema is due to increased capillary permeability. i.e. ARDS
> Do you *really* need to know the wedge pressure value to
determine or confirm that a patient has LVF?
Guy