Welcome back.
Thanks for joining me
on this discussion of postoperative care
and some of the common problems
that we may see in the postoperative period
in this section of perioperative care.
Let's first visit tachycardia.
You know, when I was a resident,
one of the things
that we were always most afraid of
is being called by the nurse to the bedside
and told that your patient had a sinus tachycardia.
Why is that?
I'll show in a second.
Look at this laundry list of potential differential diagnosis,
all of which you have to rule out.
Pain is probably one of the most common postoperative
or post-surgery causes of tachycardia.
But patients can actually be having
a myocardial infarction
or pulmonary embolism,
hypovolemia,
maybe an infection,
anxiety,
bleeding,
hypoxia,
withdrawal if the patient has history of alcohol,
or they may be developing sepsis.
And when you look at this laundry list of problems,
you can understand why we always get a little tachycardic
when we get called to the bedside
for evaluation of a patient’s sinus tachycardia.
Let's evaluate one of the causes of pulmonary embolism.
What are some risk factors for pulmonary embolism?
First, any major surgery
or any periods of immobility.
This is the perfect storm for surgical patients
because they undergo major surgery.
And for a period of time,
it may be painful due to incisions,
in which case
the patients become immobile.
How do we prevent DVTs
and subsequent pulmonary embolism?
Well, we give pharmacologic DVT prophylaxis in the setting of surgery.
Sometimes, we give the pharmacologic DVT prophylaxis
before even making incision.
The choice of DVT prophylaxis
is up to you and your institution.
There is some evidence that sequential compression devices may also help,
although, by themselves,
are not sufficient to prevent DVTs
and subsequent pulmonary embolism.
Diagnosis of pulmonary embolism
may be aided by giving an arterial blood gas.
In an arterial blood gas,
generally, we demonstrate hypoxia,
but very importantly hypocarbia.
That's because most patients with pulmonary embolism also hyperventilate,
causing a reduction in the CO2.
How do we treat pulmonary embolism?
Unfortunately,
a lot of it is up to your own body to break down the clot.
Remember, the same clot process that allows us to stop bleeding
also has a mechanism
by which clots are broken down in an organized fashion.
We give systemic anticoagulation for two reasons.
Number one,
to decrease the propagation of further clot,
both in the legs and in the lungs.
And number two,
to decrease inflammatory response.
Let's move on to a discussion of myocardial infarction
in the postoperative period.
On the far left side of the screen,
you see a normal EKG.
And as highlighted by the green bars,
you see various changes
when a patient may have a myocardial infarction.
We can see hyperacute T waves,
ST elevation,
Q waves
and T wave inversions.
And in the fourth quadrant,
you see,
when the ST elevation has improved,
depending on when you actually capture the EKG.
In patients who have had a myocardial infarction,
there may actually be Q waves
that persist even though the T waves have normalized.
Coupled with the troponin,
this may be highly sensitive for a myocardial infarction.
What happens during a myocardial infarction is that
the coronary vessels are not perfusing the heart enough with oxygen.
And our main goal of the preop workup is to predict
and try to prevent a postoperative myocardial infarction.
Remember,
patients who present with myocardial infarctions,
particularly in the postoperative period,
may have atypical symptoms.
And because the pain –
because the patient may be experiencing pain elsewhere,
it may be masked by other surgical pain.
Remember, getting EKG and a set of troponins,
these are high-value, low-cost studies.
If the patient is determined to have a myocardial infarction,
we initiate MONA therapy.
And we also start statins to reduce in-hospital mortality.
MONA stands for morphine,
oxygen,
nitroglycerin
and aspirin.
Let’s move on to fevers as potential causes of tachycardia
and fevers in general in the postoperative period.
If a clinical scenario is presented to you
in the immediate postop period,
within a few days of surgery,
the most likely cause of fevers is atelectasis.
Patients can also develop pneumonias
and urinary tract infections
in the postop period.
DVTs is also a possibility,
so are foreign objects.
Do you have a central line in?
Is there a urinary catheter infection?
Did you implant mesh during inguinal hernia repair?
Did the orthopedic surgeon put any new hardware implants in joints?
And lastly, but not –
but not any less important is
surgical site infections,
particularly deep surgical site infections,
such as intra-abdominal abscesses.
Intra-abdominal abscesses take time to form
and typically no imaging study is usually useful
until about postop day number four or five
for intra-abdominal surgeries.
A word of caution, however.
Immediate surgical site infections can be of the necrotizing infection variety.
In these patients,
there can be rapid deterioration
if the surgical site infection is not recognized.
This is why we always teach our residents and students,
look at the surgical wound.
It is potentially a common sight of postoperative fevers.