Description

Sepsis Overview:
Sepsis is a life-threatening condition where the body’s immune system reacts excessively to an infection, causing tissue and organ damage
In 2017, there were 48.9 million cases globally and 11 million deaths.
Sepsis affects anyone but is more common in the elderly, young, pregnant women, or those with chronic health conditions.

Definition:
Sepsis occurs when an infection triggers a chain reaction in the body

Pathophysiology of Sepsis:
1.Infection triggers immune response: The immune system overreacts to infections (bacterial, viral, fungal, or parasitic)
2-Release of cytokines: Cells release IL-1, IL-6, TNF-α, and other mediators, causing inflammation.
3.Vasodilation and permeability: Blood vessels dilate and leak, leading to hypotension
4-Decreased cardiac output: Blood volume drops, reducing oxygen delivery to organs
5.Tissue hypoxia and acidosis: Lack of oxygen leads to lactic acid build-up.
6.Coagulation: Impaired blood clotting results in DIC.
7-Multi-organ dysfunction: Key organs (heart, lungs, kidneys) are affected.
8-Septic shock: Persistent low blood pressure without treatment can lead to septic shock.

Causes of Sepsis:
-Bacterial infections: Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa are common.
-Viral infections: Influenza and COVID-19.
-Fungal infections: Candida and Aspergillus.
-Parasitic infections: Malaria (Plasmodium).
-Infection sources: Pneumonia, urinary tract infections, abdominal infections, and skin infections.
-Healthcare-associated infections: Infections from catheters, ventilators, or surgery.
-Weakened immunity: People with compromised immune systems (chemotherapy, organ transplants) are more vulnerable.

Clinical Features (TIME mnemonic):
T – Temperature: High fever or low temperature
I – Infection signs: Symptoms vary (e.g., cough, shortness of breath, abdominal pain)
M – Mental status: Confusion or difficulty waking
E – Extremely ill: Severe discomfort, pain, and shortness of breath

Clinical Criteria for Diagnosing Sepsis:
1,Infection suspected (bacterial, viral, fungal, or parasitic)
2.qSOFA score:
Systolic BP ≤ 100 mmHg
Respiratory rate ≥ 22 breaths/min
Altered mental status
qSOFA score ≥ 2 suggests higher risk
3.NEWS score: NEWS ≥ 5 predicts sepsis risk based on RR, BP, and oxygen levels.

Treatment for Sepsis:
Blood cultures: Obtain before starting antibiotics.
Lactate levels: Elevated lactate (≥ 2 mmol/L) indicates tissue hypoxia.
Urine output: Monitor for over 0.5 mL/kg/h to assess kidney function.
IV fluids: Start 30 mL/kg within the first hour to treat hypotension.
Oxygen therapy: Maintain oxygen saturation ≥ 94% (unless chronic respiratory issues are present).
Antibiotics: Administer broad-spectrum antibiotics within the first hour.
Vasopressors: If fluids fail to restore BP, use vasopressors (e.g., norepinephrine) to maintain a MAP ≥ 65 mmHg.
Monitoring: Track blood pressure, lactate, and urine output to ensure effective treatment.

Clinical Scenario Example:
Assessment: Patient with low BP (88 mmHg), rapid breathing, and confusion.
Treatment: Start IV fluids, monitor BP, administer vasopressors if needed, give antibiotics immediately.

Transcript

Introduction
0:00
Sepsis is a serious condition that happens when the body’s immune system has an extreme response
0:05
to an infection, and this extreme immune response causes damage to its own tissue and organs.
0:11
A study done in 2017 showed that there were 48.9 million cases worldwide, and 11 million
0:19
sepsis-related deaths in the same year. It’s a very deadly condition and it’s crucial to be able
0:25
to recognize it early, and know what to do. Sepsis can affect anyone, but people who
0:30
are older, very young, pregnant or have other health problems are at higher risk.
0:34
So, in this video, we’re going to answer the question what is sepsis?
Content
0:38
And we’re going to do that by going through the definition. Then go through the pathophysiology
0:43
for Sepsis, basically what happens within the body. Then we’re going to
0:47
talk a little bit about the causes. After that we’ll briefly go through
0:51
what the symptoms of Sepsis are using a mnemonic. Then we’re going to go
0:54
through the recent clinical criteria to be able to recognize this disease early.
0:59
And lastly, we’ll briefly talk about the measures and treatment
1:02
for this condition by using an example. So let’s start with the definition.
Definition
1:07
Sepsis is the body’s extreme response to an infection. What does that mean? It means that
1:12
sepsis starts with an infection that you already have that triggers a chain reaction throughout
1:17
your body. In 2017, the largest contributors to sepsis cases and sepsis-related mortality across
1:24
all ages were diarrhoeal diseases and lower respiratory infections. But infections in the
1:29
urinary system and skin may also cause Sepsis. Look here, a simple scheme to show how this
Pathophysiology
1:35
condition develops would look like this. In other words, the pathophysiology. Sepsis starts off
1:40
with an infection. Let’s say to there’s an infection in the lungs. A pneumonia.
1:44
Let’s take a detailed look at the lungs of this affected person, we’ll be able to see
1:49
the blood vessel. Interstitium and cell. Let’s add bacteria. Any type of common
1:53
bacterial infections, wether that may be gram positive or negative. Let’s say that
1:58
the infection is in the space between the cells and the blood vessels now. What happens is that
2:03
cells in your innate immune system, like this macrophage, is going to engulf some of these
2:07
bacteria and release inflammatory mediators. There are many things that happens simultaneously, but
2:13
the overall effect is that any damaged epithelium or activated immune cell will release these
2:18
inflammatory mediators, like prostaglandings, leukotriens, IL1, IL6, TNFa, and so on.
2:25
These inflammatory mediators are crucial to the development of a septic condition. Look here.
2:30
With all of those inflammatory mediators, we are going to attract a lot of other while blood cells,
2:35
like you see here how this neutrophil is making its way into this area. These mediators will also
2:41
cause the blood vessel to dilate, vasodilation, to increase the blood supply to this inflamed area.
2:46
And an increase in permeability, meaning that water will leak into the interstitial space.
2:52
Usually this is good. But the problem now is that what if this reaction happens in an extreme
2:58
level? What if there’s a dysregulated cytokine release, so these inflammatory mediators keeps
3:10
All of those inflammatory mediators are now in your blood stream, keep getting released by active
3:15
cells as part of a response to the infection. What happens now is that you’re gonna start
3:20
having fever. These interleukins will make their way to the temperature center in the hypothalamus
3:25
and trigger a fever, along with release of acute phase proteins like CRP, and all of those things.
3:30
Another thing that might happen is you see all of that fluid leaking out of the capillaries?
3:35
What happens when this inflammation isn’t regulated anymore? If it happens so extremely
3:40
that you start losing fluid within the actual blood vessel? You start to get
3:44
a decreased blood volume, and as a reaction to that, you get a decreased blood pressure.
3:49
And if that’s not bad enough, if you decrease the systolic BP, as well as damaging the endothelium,
3:55
inflammatory mediators can affect the cardiac return, meaning less blood enters the heart,
4:00
which again decreases the CO, or the amount of blood going out from the heart
4:05
to the body. So the body doesn’t get their normal supply of oxygen and blood anymore.
4:10
Along with all of this, you’ll also get damaged tissue. Now if we get fluid within
4:16
the interstitium you’ll get local edema which decreases the oxygen supply to our cells. And
4:21
as you know tissue hypoxia leads to an anaerobic metabolic response which can increase the lactate,
4:28
lactate is acidic. And if you decrease the CO, this might happen systemically,
4:33
within the whole body. As all of this is happening,
4:36
endothelial cells might lose their anticoagulant function after a pro inflammatory stimulation
4:42
and promote coagulation by decreasing the expression of thrombomodulin and heparin
4:46
sulfate on the cell surface, as well as increasing the expression of TF. All of
4:51
this may activate the coagulation cascade and cause a sepsis induced coagulopathy, meaning
4:57
you have a higher chances of getting blood clot. Alright so there are a whole lot of things that
5:01
happens, this is just an overview to show you that a dysregulated immune response
5:05
has a systemic severe reaction. So what actually causes Sepsis?
5:10
In most cases, a bacterial infection is the source. With agents like S aureus, Pseudomonas
5:16
and Ecoli accounting for a majority of cases. But it can be other infections aswell like viruses,
5:22
fungi and parasitic infections. The novel corona virus caused a lot of sepsis cases aswell, would
5:32
are LRT infections like pneumonia, as well as abdominal infections and from the genitourinary
5:38
tract. But it can be from any source. In elderly, infections in the urinary tract is very common.
Causes
5:44
Sepsis comes form the word septicemia, meaning blood poisoning. But the blood doesn’t necessarily
5:50
have to be contaminated to cause sepsis. It can be, the blood may be infected as well, but not
5:55
necessarily. And it’s actually also common in some cases to not find any source of infection at all.
6:02
Now How would you actually recognize the symptoms of a septic patient?
6:06
Let’s go through the Clinical features. The symptoms vary a lot, but a good mnemonic
6:11
to remember is TIME, heh just like my name. T stands for Temperature, it can be high due
6:17
to fever. Or low, since the patient has low blood pressure and also decreased CO, the circulation
6:23
will be compromised, and as a result the blood can get centralized and the patient might get
6:28
very cold. So either high temperature or low. I stands for infection, signs and symptoms can vary
6:35
a lot depending on both the causative agent and the location of the infection. So a LRT infection
6:41
give symptoms like cough and dyspnea. In the GI tract there’s diarrhea, vomit, abdominal pain,
Clinical Features
6:47
and so on. If you get a severe reaction, and you decrease the blood supply to the brain,
6:52
the patient might have an altered mental status. It’s quite common to find a septic
6:57
patient that is confused, sleepy and sometimes they may be difficult to rouse, difficult to
7:02
wake up basically. E stands for extremely ill. The patient might have a severe pain,
7:08
they may have a discomfort no matter the position they’re lying in. and They may have a SOB.
7:12
So those are the main symptoms related with Sepsis.
7:16
Now sepsis is a clinical diagnosis, and it’s crucial to recognize the
7:21
possibility of sepsis early, preferably within seconds to minutes. And this is
7:26
done primarily through some screening tools. So recent guidelines, at least from -21 till date
7:31
of making this video. Suggest that first, there has to be a presence of infection. That’s number
7:37
one. You see a patient, you suspect an infection. That’s number one. Together with the infection,
7:42
there are two screening tools that is used nowadays to be able to identify patients at
7:47
high risk of spesis. It’s the quick SOFA, and NEWS. The qSOFA score ranges from 0-3,
7:53
with 1 point each for sustolic hupotention of 100 or under, tachypnea of 22 breaths or higher
Clinical Criteria
8:00
per minute, or altered mental status. A qSOFA score of 2 or above points has a predictive
8:06
value for sepsis. The other screening tool is the national early warning score, or NEWS. NEWS is a
8:13
scoring system derived from the 6 physiological parameters, including RR, oxygen saturation,
8:19
systolic blood pressure, HR, altered mental status and the temperature. And here, a score of 5 or
8:25
above can be used to predict the chance of sepsis. So the way this goes is that there has to be
8:30
presence of an infection, plus qSOFA score 2 or above, or NEWS score 5 or above. There
8:37
are other scoring systems aswell such as SIRS criteria, but recently there has been
8:42
a shift of usage from SIRS to qSOFA and NEWS. Now, you’ve found out the possibility of Sepsis,
8:48
what do you do first? So first we have to secure blood cultures prior to antibiotics
8:53
administration. Because we need to localize the infection, as well as find out about the causative
8:57
agent for later targeted therapy. Then we need to measure Lactate, as we said earlier, if you have
9:03
a tissue hypoxia, that may lead to anaerobic metabolism which might increase the lactate.
9:08
There are many factors that influence the lactate levels here. Anaerobic metabolism is one cause,
9:13
but it can also be causes like decreased hepatic clearance, increased b adrenergic
9:18
stimulation and so on. Lactate is a very important prognostic tool to see the severity of sepsis.
9:25
And we have to measure the urine output. Why do we need to check the urine output? You check
Measures/Treatment
9:30
the urine output as a way to check for organ dysfunction. If you have an organ dysfunction,
9:36
the kidneys won’t be able to filter the blood optimally and you’ll have a decreased to none
9:40
urine production. So you want to maintain a urine production higher than 0.5 ml/kg/h, This
9:48
is also a way to check the severity of sepsis. Then we have to give IV fluids. This is a crucial
9:54
part because remember our main problem right now is that we have a decreased BP and decreased blood
10:00
volume. We also need to try to keep a oxygen saturation above 94%, primarily for people
10:07
with healthy lungs from before. If they have any respiratory illnesses from before you’d want this
10:12
number to be lower, to not get CO2 retention. Then we need to treat the cause of sepsis. So
10:18
we give empiric antibiotics first, then a targeted therapy later when the causative agent is known.
10:23
So these are the general measures. Now let’s put this to practice.
10:27
Imagine you’re working late at the hospital, and you get called to go
10:30
check on a patient that is admitted for an infection. They’ve gotten worse. They have
10:34
a systolic blood pressure of 88. They breath fast, and they have an altered mental status.
10:40
So you already know within seconds that this patient has an infection and have a
10:44
qSOFA score of 2 or above or a NEWS score of 5 or above. So the sepsis diagnosis is
10:50
established within seconds. What do you do now? You’re standing next to the patient.
10:54
We start fluid resuscitation. So we start an IV crystalloid solution, give a bolus of 500ml,
11:00
and we continue to give fluids up until 30ml/kg given within the first hour,
11:06
with continuous monitoring of blood pressure. We have to secure 2 IV lines just in case.
Clinical Scenario Example
11:12
And we need to consider a urine catheter. I say consider because not all patients need it,
11:17
some patients can still give an estimate on the urine output. Again this is to check
11:21
the severity of organ dysfunction. Then after that we need to remeasure. Do the
11:26
patient have a persistent hypotention or not? If the patient has a persistent hypotention
11:32
without hypovolemia. Then that is enough to think that this is a septic shock. So we have to
11:38
start some type of pressors to increase the blood pressure again using drugs like noradrenaline. If
11:43
the patient now ahs a higher blood pressure after giving fluid. We continue to give fluid, while
11:49
now we also need to start giving antibiotics. And for that you need to check the guidelines,
11:54
because there are ifferent antibiotics you give based on the location of the infection,
11:58
and also the endemic region, country, the patient is located in. And so the antibiotics has to be
12:03
started within the first hour. Then after that, we need to set a treatment goal. Usually we want the
12:10
patient to be stable within the first 6 hours. So we want to keep a mean arterial pressure of
12:16
above 65, we want to keep a urine output of higher than 0.5 ml/kg/h,
12:22
and we need to strive for an oxygen saturation within acceptable value, that is 94% for people
12:29
with healthy lungs. And a little bit lower for people with known respiratory diseases like COPD.
12:35
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