Multiple organ dysfunction syndrome (MODS): Clinical sciences

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Introduction0:00–0:55

Multiple organ dysfunction syndrome or MODS is a life-threatening condition that occurs in the setting of shock. Now, a condition that precedes MODS is a systemic inflammatory response syndrome, or SIRS for short, which can be triggered by both infectious and non-infectious causes, including burns and trauma.
Now, no matter what the initial trigger is, in SIRS, the immune system overproduces inflammatory cytokines and mediators, such as TNF-alpha, as well as IL-1, IL-6, and IL-8.
This overproduction of inflammatory cytokines is often referred to as “cytokine storm”, and in combination with prolonged hypotension, it can lead to hypoperfusion of multiple organs, hypoxic damage, and progressive organ dysfunction.
Now, if you suspect MODS, immediately perform an ABCDE assessment and begin acute management. Start by stabilizing their airway, breathing, and circulation, which means that you might need to intubate the patient.

ABCDE Assessment0:55–1:43

Next, obtain IV access, start IV fluids, and consider placing a central venous catheter for the administration of medications and hemodynamic monitoring.
Additionally, you can insert an arterial catheter for continuous monitoring of the mean arterial pressure or MAP; or you may also place a pulmonary artery catheter or PAC to measure hemodynamic parameters and guide the administration of IV fluids and even vasopressors.
Finally, put your patient on continuous vital sign monitoring, including heart rate, blood pressure, and pulse oximetry.
Now, once you stabilize the patient, perform a focused history and physical examination and obtain labs, including a CBC, CMP, lactate, ABG, as well as cardiac enzymes and BNP.

Focussed H&P and Labs1:43–1:57

Next, use physical exam findings and some of the lab values to perform the SIRS assessment, which is based on four main criteria.

SIRS assessment1:57–3:14

The first criterion is either leukopenia, defined as WBCs below 4,000, leukocytosis, defined as WBCs above 12,000, or bandemia, defined as bands greater than 10% bands.
The second one is body temperature either below 36 ൦C or over 38൦C; while the third one is a heart rate above 90 beats per minute.
Finally, the last criterion includes respiratory rate over 20 breaths per minute.Now, the SIRS criteria is not met if your patient presents with less than 2 criteria, so you should consider an alternative diagnosis.
On the flip side, SIRS criteria is met if there are 2 or more criteria present. In these individuals, your next step is to assess for signs and symptoms of hypoperfusion, primarily by checking their systolic blood pressure, peripheral pulses, and capillary refill time, and if available, labs to check lactate levels!Systemic blood pressure over 90 mmHg, normal peripheral pulses, and normal capillary refill time, as well as normal lactate levels below 2 mmol/L are suggestive of normal organ perfusion, so in these individuals, you should consider alternative diagnoses.

Assess hypoperfusion3:14–4:52

On the flip side, systemic blood pressure less than 90 mmHg, weak peripheral pulses, and prolonged capillary refill time, as well as elevated lactate levels above 2 mmol/L are usually associated with organ hypoperfusion, so your patient is likely experiencing shock!
Now here’s a high yield fact to keep in mind! MODS can be caused by almost any type of shock, but the most common ones include septic and hypovolemic shock!
Suspect septic shock if your patient reports a fever, has a known or suspected infection, and if their labs reveal leukocytosis, but some cases may have leukopenia, neutropenia, or bandemia greater than 10%.
Also, if initial blood lactate levels are twice above the normal limit, so above 4 mmol/L, you should be suspicious for severe sepsis.
On the other hand, suspect hypovolemic shock if they report a history of trauma or burn injury and if their labs show abnormal hemoglobin levels.
Moreover, low hemoglobin levels, or anemia, are a specific sign of hemorrhagic shock, while high hemoglobin levels, or hemoconcentration, are highly suggestive of non-hemorrhagic shock.Okay, now that you’ve diagnosed shock, your next step is to assess for organ system failure.

Assess organs systems4:52–5:59

Suspect neurologic failure in patients with altered state of consciousness or encephalopathy. Think of heart failure if your patient presents with pitting edema and elevated cardiac enzymes and BNP.
Next up is respiratory failure, which is associated with signs and symptoms of respiratory distress, such as shortness of breath, use of accessory inspiratory muscles, and cyanosis.
Additionally, ABG findings of hypoxemia and hypercapnia confirm the diagnosis of respiratory failure. Next up is liver failure, which typically manifests with jaundice, as well as elevated liver function tests or LFTs.
Suspect renal failure if urine output is decreased, or if BUN and creatinine become elevated above baseline. Finally, think of hematologic failure if your patient develops easy bleeds, coagulopathy, or disseminated intravascular coagulation or DIC.
If 2 or more organ systems are affected, you can diagnose MODS and begin treatment.Since the central problem underlying MODS is inadequate tissue perfusion, the primary goal in treatment is hemodynamic management and monitoring to maintain adequate tissue perfusion.

Treatment5:59–7:01

This may require IV fluid volume resuscitation, maintenance IV fluids, infusion of vasopressors and inotropes, and even transfusion of blood products.
You can use several methods to guide hemodynamic management, including periodic assessment of the systolic blood pressure, continuous monitoring of the mean arterial pressure, and following serial lactate levels.
Once the patient is hemodynamically stable, the secondary goal in MODS treatment is to treat the underlying cause. If an infection has led to septic shock, you’ll administer empiric broad spectrum antibiotics to address the underlying infection.
On the other hand, if bleeding due to trauma led to hemorrhagic shock, you’ll want to stop the bleeding, so don’t hesitate to consult the surgical team, and transfuse blood products, if not already done, to support the hemodynamics.
Alright, as a quick recap... Multiple organ dysfunction syndrome or MODS is a life-threatening condition that occurs in the setting of shock, when prolonged hypotension leads to hypoperfusion of multiple organs, hypoxic damage, and progressive organ dysfunction.

Review7:01–8:42

If you suspect MODS, use SIRS criteria to assess the patient’s WBC count, body temperature, heart rate, and respiratory rate.
The SIRS criteria is not met if your patient presents with less than 2 criteria. In this case you should consider an alternative diagnosis.
On the flip side, the SIRS criteria is met if there are 2 or more criteria present. In this case, your next step is to assess for signs and symptoms of hypoperfusion, primarily by checking the patient’s systolic blood pressure, peripheral pulses, and capillary refill time, as well as labs to check lactate levels!
If systemic blood pressure is over 90 mmHg, peripheral pulses are normal, capillary refill time is normal, and lactate level is less than 2 mmol/L, you should consider alternative diagnoses.
On the flip side, systemic blood pressure less than 90 mmHg, weak peripheral pulses, prolonged capillary refill time, and lactate levels greater than 2 mmol/L are highly suggestive of organ hypoperfusion and shock!
Okay, now that you’ve diagnosed shock, your next step is to assess for organ system failure. If 2 or more organ systems are affected, you can diagnose MODS and begin treatment, which includes hemodynamic management and monitoring, treatment of the underlying cause, and surgical consultation if needed.