Compartment syndrome: Clinical sciences

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Introduction0:00–0:51

Acute compartment syndrome is a surgical emergency that occurs when muscle compartments which are bounded by noncompliant fascial membranes have an increase in pressure causing tissue ischemia.
Although it's usually associated with extremity trauma, any condition that increases intracompartmental pressure can lead to compartment syndrome.
Acute compartment syndrome is typically a clinical diagnosis, but you can confirm the diagnosis of unclear cases with a direct measurement of compartment pressures.
Compartment syndrome can lead to irreversible tissue damage, requiring amputation without rapid diagnosis and surgical decompression by fasciotomy.

Unstable patient0:51–4:53

When assessing a patient with signs and symptoms, suggestive of acute compartment syndrome. First perform an ABCDE assessment to determine if the patient is unstable or stable.
If the patient is unstable, start acute management immediately to stabilize their airway breathing and circulation. This means that you might need to intubate the patient obtain IV access, begin fluid resuscitation and monitor their vitals before continuing with your assessment.
Once this important step is complete, obtain a focused history and physical exam as well as labs like CBC CMPC PK and lactate.
Now, let's first look at history. The patient might present with ongoing severe extremity pain, swelling and rapid progression of symptoms over a few hours.
You can also suspect some causes of acute compartment syndrome based on history. The patient may have a known history of extremity trauma such as a fracture, burn or crush injury.
They might have a history of prolonged ischemia with reperfusion such as a recent surgical revascularization procedure. Other causes include extended immobility or extreme exercise which can lead to rhabdomyolysis and even massive DVT like phlegmasia caerulea Dolens.
Ok. The exam may reveal tachycardia and hypotension as well as a tense wood like muscle compartment on palpation, motor paralysis and sensory loss.
Physical exam findings can also include skin changes like power or modeling as well as polo theia or skin that is too cold to the touch and as a late sign, weak or absent extremity pulses.
Additionally, a key sign that's considered compartment syndrome until proven otherwise is pain in the leg with passive stretching of the muscles such as pain in the leg with passive dorsiflexion of the foot.
It is important to always perform a thorough neurovascular examination of the affected extremity. Because after more than six hours of ischemia, tissue damage can become irreversible.
Signs of severe ischemia include foot drop from peroneal nerve injury or Ulman's contracture in the arm which results in a claw like deformity of the hand.
If tissue necrosis has already occurred, a secondary soft tissue infection may also be present. Here's a clinical pearl.
The lower leg consists of four muscle compartments, anterior lateral superficial posterior and deep posterior. However, the deep posterior compartment cannot be palpated on physical examination.
Finally, labs might reveal leukocytosis, electrolyte abnormalities such as hyperkalaemia. And in some cases, even evidence of acute kidney injury such as an elevated bun to creatinine ratio, as well as an elevated CPK lactate can also be elevated since it's released by damaged cells.
If you see these signs and symptoms, you can diagnose acute compartment syndrome. Now that the diagnosis is made, let's talk about treatment.
Compartment syndrome is an emergency. So the first thing to do is call the surgical team for consultation.
Then immediately start with supportive care, which includes IV, fluid resuscitation, correction of electrolyte abnormalities, broad spectrum antibiotics, supplemental oxygen and pain management as needed.
Once ready, the surgical team will perform emergent fasciotomy, finally treat the underlying cause if found. Ok.

Stable patient4:53–6:12

Now that the unstable patients are taken care of, let's return to the ABCD E assessment and talk about stable patients. Your first step here is to obtain a focused history and physical exam as well as labs like CBC CMP, CPK and lactate.
Now, history and labs are usually similar in all patients with compartment syndrome. The history might reveal pain paresthesias such as pins and needles sensations or numbness and rapid progression of symptoms.
Over a few hours as before patients might report traumatic injuries such as fractures, burns, crush injuries, or even a new constrictive cast or bandage.
You should also look out for other causes such as animal bites and stings, prolonged ischemia and reperfusion, spontaneous hemorrhage or hematoma and even extravasation of IV fluid medications or drugs.
On the flip side, labs typically reveal leukocytosis, electrolyte abnormalities such as hyperkalaemia and elevated CPK and lactate.
Now, the real difference in presentation is the physical exam. Some patients might present with clear findings of compartment syndrome.

Clear findings6:12–7:32

In this case, the physical exam reveals pain out of proportion to physical findings, extremity swelling, a tense wood like muscle compartment on palpation and pain to passive stretch.
They may even have motor or sensory deficits depending on the duration and severity of the limb ischemia. If you see these clear findings, you can make a clinical diagnosis of acute compartment syndrome.
As before. Since this is an emergency call, the surgical team for a consult and possible fasciotomy at the same time, start supportive care including IV fluids and supplemental oxygen.
Take steps to maximize tissue perfusion such as with limb elevation to the level of the heart. Now, this will decrease arterial blood flow but it will also increase venous drainage and decrease swelling and help relieve pressure as well as removing or relieving any external constriction like casts or bandages.
Finally administer analgesics if needed for pain management. Once again, remember to treat the underlying cause.

Inconclusive findings7:32–8:45

Now let's go back to the H AND P and discuss patients who present with inconclusive findings of compartment syndrome. In this case, the physical exam might only reveal leg swelling, absent or mild pain to passive stretch and no motor or sensory deficits.
Exam findings might also be inconclusive in patients who are unable to participate in their physical exam or reliably express how they're feeling.
If this is the case, you might suspect acute compartment syndrome, you should initiate the same supportive care with IV fluids, supplemental oxygen, limb elevation, removing or relieving external constriction of the limb and pain management.
Once supportive care is started measure the compartment pressure to confirm your diagnosis. Here's a clinical pearl.
There are several ways to obtain a compartment pressure reading. There's a special handheld manometer made just for this purpose.
However, if you don't have one readily available, you can create your own manometer by attaching an 18 gauge needle to an arterial line set up to measure compartment pressures.
All right. Now that you have measured the compartment pressure, let's talk about the results.

Compartment pressure8:45–9:56

If your patient's compartment pressure is greater than or equal to 30 millimeters of mercury, or if the delta pressure, which is the difference between the compartment pressure and the patient's diastolic BP is less than or equal to 30 millimeters of mercury, then you can diagnose acute compartment syndrome.
If this is the case call the surgical team for an emergent fasciotomy as before, remember to treat the underlying cause.
However, let's say you measure the compartment pressure and the absolute value is less than 30 millimeters of mercury and the delta pressure is more than 30 millimeters of mercury.
At this point, continue to closely monitor the patient hourly or even more frequently if needed with serial extremity or compartment exams and assess their response to supportive care.
Don't limit your exam to simply palpating the muscle compartments of concern. Always perform a thorough neurovascular exam too.

Adequate and inadequate response9:56–11:05

Next, assess the patient's response to treatment if the patient has an adequate response where symptoms and exam findings improve over the next several hours to days, you can rule out acute compartment syndrome.
Go ahead and continue supportive care and treat the underlying cause. Ok.
Let's switch gears and talk about patients with inadequate response to treatment. If the patient's symptoms or exam findings are worsening, you should immediately remeasure the compartment pressure.
All right, if the repeat compartment pressure measurement is now greater than or equal to 30 millimeters of mercury or if the delta pressure is less than or equal to 30 millimeters of mercury, you can diagnose acute compartment syndrome at this point.
Call the surgical team for an emergency fasciotomy and be sure to treat the underlying cause as well. Finally, if the repeated compartment pressure measurement is still less than 30 millimeters of mercury or the delta pressure is over 30 millimeters of mercury.
Consider an alternative diagnosis. All right, as a quick recap.

Review11:05–12:35

Acute compartment syndrome is a surgical emergency, unstable patients should be rapidly assessed and treated surgically as the extremity might not be viable.
On the other hand, stable patients may present with findings on physical exam that indicate compartment syndrome. When the clinical diagnosis is clear, such as a patient with a tense wood like compartment and pain to passive stretch immediately, call for a surgical consultation for an emergency fasciotomy and treat any underlying causes.
However, if the exam findings are inconclusive measure the compartment pressures directly. If any compartment pressure is greater than or equal to 30 millimeters of mercury, or if the delta pressure is less than or equal to 30 millimeters of mercury call a surgical consult for a fasciotomy and treat any underlying causes when the clinical diagnosis is clear, such as a patient with a tense wood like compartment and pain to passive stretch immediately, call for a surgical consultation for an emergency fasciotomy and treat any underlying causes.
However, if the exam findings are inconclusive measure the compartment pressures directly, high compartment pressure or low delta pressure requires fasciotomy.
Normal compartment pressure and delta pressure should be managed with supportive care and hourly reassessment.