00:00
Now, let's visit the initial priorities and treatment of a patient with septic shock. First, your goal
is to stabilize the patient. Remember, stabilization of the patient goes beyond just the fluid
resuscitation or potentially using medications such as norepinephrine to augment the mean
arterial blood pressure. It's very important to contain the source of infection or injury. For
example, if your patient has a perforated appendicitis causing generalized peritonitis, that
patient should have appropriate drainage and source control in addition to the other measures
taken to stabilize the patient. As clinicians, we should be goal-driven, although some of these
recommendations are being re-tested. It's generally safe to assume that if you can meet these
goals your patient is likely perfusing. First, we like to maintain a mean arterial pressure
somewhere around 65 mmHg. Next, we want to maintain a urine output greater than or equal
to 0.5 cc/kg/hour. This is indicative of appropriate kidney perfusion. Next, we want to try to
maintain a central venous pressure if you have a central line in place between 8 to 10 mmHg.
01:14
This item is potentially the most controversial currently. Lastly, we can obtain what's called
a central venous oxygenation. Traditionally when patients have had septic shock, we used to
put pulmonary artery catheters in place. As a practice _____ has moved away from pulmonary
artery catheters, we were unable to get true mixed venous gases. As a reminder, a true mixed venous
gas is obtained at a location distal to the coronary sinus. At reflex, the difference between
supply and demand. An ScvO2 level of greater than 70% or a true mixed venous gas greater
than 65% is indicative of acceptable perfusion. Now, how do you resuscitate the patient?
We generally use crystalloid volume. If a clinical scenario presents to you and gives you various
different fluids, remember studies have shown no difference in terms of using crystalloid and
colloid volume resuscitation. In fact, colloid volume resuscitation may lead to worse outcomes.
02:24
Sometimes we need to initiate vasopressors. Remember I mentioned the medication
norepinephrine. There are various vasopressors that are necessary to maintain a perfusion
pressure. Next, cardiac contractility is incredibly important for perfusion. You can have
adequate RBCs and oxygen levels but if the pump is not working no oxygen is actually being
delivered to the surrounding tissues. Sometimes, patients particularly with cardiac dysfunction
may need a little bit of augmentation. This is a class of medications called ionotropics. Lastly,
because the vast majority of septic shock patients have an ongoing infection, it's important
to start empiric antibiotics early on. The theory behind empiric antibiotics is we may not know
the exact bug or virus that's involved but we want to cover it by being broad in terms of initial
coverage. As a microbiology studies come back, we should tailor our antibiotics. You always
want to be a good antibiotics steward. This is my favorite picture. This is called "The Fishing
Expedition." Remember, oftentimes patients appear quite sick and you have a laundry list of
differential diagnoses. In particular, patients who are deteriorating we go on a Fishing
Expedition with cross-sectional imaging to look for potential sources of infection. Remember,
anything is possible, although the clinical history and physicals oftentimes guide you into the
most likely 1, 2 and 3 diagnoses. Remember, source control is of the utmost importance and
sometimes patients say "surgeons are great for source control," and we are. Here, you see a
picture of a severe necrotizing soft tissue infection. Remember, a clinical scenario may be
presented to you with the patient who has septic shock has a picture similar to this and may
have a history of diabetes. The next step of management for this patient is the operating room.
04:26
This patient needs an extensive debridement for surgical source control. Unfortunately, no
amount of volume or pressors could help this patient. In this example, you see free air under
the diaphragm. That's called pneumoperitoneum. Remember, pneumoperitoneum on an
abdominal x-ray only tells you that there is likely perforated viscus, not exactly sure where the
viscus is. What would your next management step be in this situation? I'll give you a second to
think about it. That's right, of course, exploratory laparotomy. Take this patient to the
operating room. Next, let's look at this. Remember from our vascular discussion? What about
gangrenes of the toe? There's a difference between wet gangrene and dry gangrene? Wet
gangrene needs surgical debridement right away. You also notice that there's some cellulitis
on the left side of the screen. Patients with cellulitis and an abscess require antibiotics.
05:26
Surgical source control in this situation may involve amputation. How about this cross-sectional
imaging of the chest? You notice on the right side of the screen on the left lower lobe is likely
a pneumonia or infiltrate. Unfortunately, there is no surgical source control for pneumonia but
that's why the broad-spectrum empiric antibiotics are in place. Now, I'd like to help you
understand lactate a little bit better. Lactate is a sign of anaerobic metabolism. Remember, we
use glucose to generate ATP. This system includes glucose 2 pyruvate and in the sense of
aerobic metabolism, pyruvate is then fed into the ATP cycles but in anaerobic metabolism when
there's lacking perfusion such as septic shock patients, that pyruvate feeds into lactate.
06:24
To _____ mechanisms in oxidases, this patient develops an accumulation of lactate.
06:31
Physiologically, lactate in in of itself is not harmful. In fact, lactate can be used in the Cori cycle
turn back into glucose to deliver. Unfortunately, with continued malperfusion or hypoperfusion
and persistent anaerobic metabolism, lactates will continue to build. As a plasma level, when you
see lactates continue to rise it's very suggestive that the tissue beds are not getting enough
oxygen. This may be a marker for further resuscitation. Now, remember "Whatever is necessary,
but don't delay." That's the mantra for surgery. If you need to go to the operating room to
take out the emphysematous gallbladder, do it. If you have necrotizing soft tissue infection,
go to the operating room. The most important thing is don't delay. Similarly on a standardized
examination when presented with a clinical scenario and a clear source of infection that's
surgical in nature, your next step in management should be to the operating room. Now, it's
time to re-visit some important clinical pearls and high-yield information. Remember, as
frustrating as it can be, patients may not demonstrate a clear diagnosis and yet you need to
treat. Therefore, understand the initial priorities in stabilizing the patient. As intensivist,
oftentimes I don't know the diagnosis, although I have some suspicions I start treating.
07:59
Remember, if the patient is deteriorating clinically, proceed to surgery if there is a source
control issue whether that's in the chest, abdomen, pelvis or elsewhere. Don't delay, don't get
further diagnostic studies. Thank you very much for joining me on this discussion of sepsis.