Compartment Syndrome

30 mm Hg REF: With text

“Setting the threshold for fasciotomy at a perfusion pressure of 30 mmHg can be considered safe, but still may lead to overtreatment if used routinely” REF: Evidence-based Orthopedics – Mohit Bhandari Page 634

Different authors consider surgical intervention if: (REF: Tiwari A, Haq A I, Myint F, Hamilton G. Acute compartment syndromes. Br J Surg 2002; 89: 397-412.)

1. Absolute ICP greater than 30 mmHg
2. Difference between diastolic pressure and ICP greater than 30 mmHg
3. Difference between mean arterial pressure and ICP greater than 40 mmHg

“Intracompartmental pressure may be measured by the wick catheter in patients suspected to have compartment syndrome. By such method a pressure of 30 mm Hg or more sustained for 6-8 hours or more is a likely indication for decompressive fasciotomy” REF: Skeletal injury in the child by John Anthony Ogden Page 317

REF: Mastery of vascular and endovascular surgery – Gerald B. Zelenock, Thomas S. Huber, Louis M. Messina Page 507

• Compartment syndrome (CS) occurs whenever increased tissue pressure in a myofascial compartment compromises blood flow to the muscles and nerves within that compartment, resulting in tissue and nerve damage. The compartments of the lower leg and the volar forearm are particularly prone to developing elevated compartment pressures.
• In posterior compartment syndrome, patient keeps foot in a position of plantar-flexion to maximally relax the fascia/muscles And there occurs pain on dorsiflexion, due to passive stretching of posterior leg muscles.

Acute compartment syndrome occurs when the tissue pressure within a closed muscle compartment exceeds the perfusion pressure and results in muscle and nerve ischemia.

Compartmental pressures higher than 30 mm Hg require surgical intervention.

If such high compartmental pressures are left untreated, within 6-10 hours, muscle infarction, tissue necrosis, and nerve injury occur.

Exercise may increase intracompartmental pressure and muscle edema, so it is avoided in case of acute compartment syndrome.

Ref: Tachdjian’s Pediatric Orthopedics 3/e, Page 2139-77, 2060; Rockwood and Green’s Fracture in Children 6/e, Page 543-86; Apley’s 8/e, Page 596-99, 563-64; Watson Jones : Fracture and Joint injuries 6/e, Page 591-609.

The deep posterior compartment contains the flexor hallucis longus, flexor digitorum longus, and posterior tibialis muscles, as well as the posterior tibial nerve. In deep posterior compartment syndrome, patient keeps the foot in a position of plantar flexion to maximally relax fascia/muscles. Pain occurs on dorsiflexion , due to passive stretching of posterior leg muscles

B i.e. Dorsiflexion of foot 

A i.e. Fracture

B i.e. Pain on passive stretch is reliable sign > C i.e. Fasciotomy is earliest management

D i.e. Excercise

Excercise may increase intra compartmental pressure & muscle edema, so it is avoided in cases of acute compartmental syndromeQ.

A i.e. Pulse is a reliable indicator

• In compratment syndrome the order of compression of vascular structures with increase of intra compartmental pressure is : capillary compression venous compression arterial compression . That’s why pulselessness is a late feature and it can’t be used as a reliable indicator of compartment syndromeQ. The presence of pulse does not exclude the diagnosis.
• A split catheter is introduced into compartment & the pressure is measured close to the level of fracture. A differential pressure (Ap) – the difference between diastolic pressure and compartment pressure – of less than 30 mm Hg (4. 00 kPa) is an indication of immediate compartment decompressionQ (fasciotomy).
• If facilities of measuring compartmental pressure are not available , the limb should be clinically assessed at 15 minutes interval and if there is no improvement with in 2 hours of removing the dressing fasciotomy should be performed. Muscle will be dead after 4- 6 hours of total ischemia – there is no time to loose.

A i.e. Fractures

A i.e. Fasciotomy

D i.e. Do operative decompression of fascial compartment

C i.e. Normal sensation distally

Compartment Syndrome

– Tibial diaphyseal fractures is the most common cause of compartment syndromeQ (overall and in adults); in children the most common cause is fracture supracondylar humerusQ.

In a recent study it has been reported that 69% of compartment syndromes are associated with fracturesQ and 36% of all compartment syndrome are associated with tibial diaphyseal fractureQ.

With the improved results associated with intramedullary nailing of tibial fractures, compartment syndrome has become the commonest serious complication of closed tibial fractures. An open fracture does not protect the patient from compartment syndrome.

It mainly affects young male and is best detected by compartment pressure monitoringQ.

Most of the classical symptoms of compartment syndrome only occur only after there has been irreversible soft tissue damageQ. If the surgeons wait for paresthesia, paralysis, or pulselessness, the patient is highly unlikely to recover full function and it is probable that myonecrosis will already have started. If clinical suspicion is to be used for diagnosis, the diagnosis must be based on increased painQ (disproportionate) and pain on passive muscle stretchQ, as these clinical signs usually occur at an earlier stage. It is extremely difficult to diagnose compartment syndrome clinically, and this problem is exacerbated by the fact that a number of patients will be pain free, unconscious, on ventilators, or anesthetized when compartment syndrome becomes clinically important. When monitoring it is only necessary to record the pressure in the anterior compartment (as it is involved in all cases). The pressure is highest nearer the fracture site, it is there fore important to locate the tip of the catheter near to the fracture site to ensure that the muscle with the highest pressure is monitored. Continuous pressure monitoring is better than single reading.

Surgeons use a single pressure level, usually 30 mm He, or a difference between intra compartment pressure and diastolic blood pressure (diastolic BP – ICP) < 30 mmHgQ as an appropriate criteria to base the decision to undertake fasciotomy.

Subtotal fasciotomy should never be undertaken. All four compartments should be decompressed. Compartment decomression (fasciotomy) should be performed immideatelyQ as delay carries risk of permanent dysfunction.

C. i.e. Toe dorsiflexion 

Compartment syndrome is clinically diagnosed by high index of suspicion in any patient with pain out of proportion to injury, who is unresponsive b/O associated head or other injury. Physical findings that warn are pain on passive range of motion of toes causing affected compartmental muscles stretchQ, and tense compartments that are tender on palpation.

So compartment syndrome affecting posterior leg can be earliest diagnosed by passive stretch of toe plantiflexiors that occurs during (passive) toe, dorsiflexion movementQ.

Ans is ‘a’ i.e. Intraabdominal pressure > 15 cm H₂O

Abdominal Compartment syndrome

Is caused by acute increase in the intraabdominal pressure, caused by accumulation of large amounts of fluid i.e. blood or edema

It is seen in patients

-who have sustained massive abdominal trauma

had an operation for massive intraabdominal infection or

undergone a complicated prolonged abdominal operation

The Normal intraabdominal pressure (IAP) is nearly 0 cm of H₂0 and large amounts of fluid accumulation is needed before it begin to rise.

• When the IAP exceeds 15 cm F1₂0, serious physiological changes begin to occur.
• The lungs are compressed by the upward displacement of the diaphragm. This causes a decrease in functional residual capacity, increased airway pressure, and ultimately hypoxia. a)

–   Cardiac output decreases due to diminished venous return to the heart and increased afterload.

–  Both venous return and arterial perfusion of every intraabdominal organ especially kidneys are severely compromised. This leads to oliguria which may progress to anuria.

As IAP exceeds 25 to 30 cm of H₂O life threatening hypoxia and anuric renal failure occurs. 

Management

• The diagnosis is made by measuring bladder pressure (through Foley catheter). It represents the intraabdoinal pressure.
• Abdominal compartment syndrome is a surgical emergency and treatment includes rapid decompression of the elevated intraabdominal pressure by opening the abdominal wound and performing a temporary closure of the abdominal wall with mesh or a plastic bag. Permanent closure is done 5 to 7 days later when the condition resolves.
• IAP pressures less than 15 mm of 11₂0 do not require decompression.

Ans is A (Cardiac Output), C (Venous return)

Ans. D i.e., Oliguria due to ureter obstruction 

• ACS is defined as increased intra-abdominal pressure (IAP >20 mm Hg) resulting in compression of abdominal structures, producing fatal complications due to pulmonary failure and mesenteric vascular compromise.
• Normal IAP= 5-7 mmHg; Intra-abdominal hypertension IAP ≥ 12 mmHg
• ACS occurs predominantly in:

1. Patients in profound shock
2. Patients requiring large amounts of resuscitation fluids and blood

• Those with major visceral or vascular abdominal injuries
• ACS is characterized by a sudden increase in intra-abdominal pressure, increased peak inspiratory pressure, decreased urinary output, hypoxia, hypercapnia, and hypotension are secondary to decreased venous return to the heart.

Decreased :

• Cardiac output
• Venous return
• Visceral blood flow
• Renal blood flow
• Glomerular filtration

Increased :

• Cardiac rate
• Pulmonary capillary wedge pressure
• Peak inspiratory pressure
• Central venous pressure
• Intrapleural pressure
• Systemic vascular resistance

Ans. is ‘a’ i.e., Fracture supracondylar humerus

Compartment syndrome is most commonly caused by extremity fractures :-

1. Supracondylar fracture of humerus is the most common cause is children.
2. Crush injuries to forearm are the most common cause in adults.
3. Other injuries are fracture both bones forearm, elbow dislocation.

Ans. is ‘b’ i.e., Vertigo

Answer A) Pain

Compartment syndrome

• Condition in which increased pressure within one of the body’s anatomical compartments results in insufficient blood supply to tissue within that space.
• There are two main types: acute and chronic.
• Compartments of the leg or arm are most commonly involved.

Signs and symptoms

Acute

• There are five characteristic signs and symptoms related to acute compartment syndrome:

1. Pain
2. Paraesthesia (reduced sensation)
3. Paralysis
4. Pallor
5. Pulselessness. 

• Pain and paresthesia are the early symptoms of compartment syndrome.

Common

• Pain – A person may experience pain disproportionate to the findings of the physical examination. This pain may not be relieved by strong analgesic medications. The pain is aggravated by passively stretching the muscle group within the compartment. However, such pain may disappear in the late stages of the compartment syndrome. The role of local anesthesia in delaying the diagnosis of compartment syndrome is still being debated.
• Paresthesia (altered sensation) – A person may complain of “pins & needles”, numbness, and a tingling sensation. This may progress to loss of sensation (anesthesia) if no intervention is made.

Uncommon

• Paralysis – Paralysis of the limb is a rare, late finding. It may indicate both a nerve or muscular lesion.
• Pallor and pulselessness – A lack of pulse rarely occurs in patients, as pressures that cause compartment syndrome are often well below arterial pressures. Absent pulses only occur when there is arterial injury or during the late stages of the compartment syndrome, when compartment pressures are very high.
• Pallor can also result from arterial occlusion.

Chronic

• The symptoms of chronic exertional compartment syndrome, CECS, may involve pain, tightness, cramps, weakness, and diminished sensation.