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Hospital Treatment
 #95
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Primary survey, stabilization and resuscitation, secondary survey
Diagnosis through examination and confirmation with tissue pressure measurements
Treat systemic effects of compartment syndrome similar to crush injury
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If injury is open:
antibiotics, tetanus, thorough cleansing
debridement of nonviable tissues
early amputation for severely injured limbs may be required to reduce sepsis
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Teaching Tip
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Continue to use a scenario and patient cases to explain crush injury and compartment syndrome.
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Fasciotomy
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Fasciotomy is definitive treatment, but tissue pressure at which it is required is controversial. Varying views include:
early fasciotomy when pressures >45 mm Hg or when within 20 mm Hg of diastolic pressure
delayed fasciotomy (beyond 48-72 hours) increases risk of sepsis and death due to extensive necrotic tissues
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Objective
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Describe the procedural skills needed for management of compartment syndrome, including measuring compartment pressures, use of ketamine, and fasciotomies.
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Procedural Skills: Measuring Compartment Pressure
#96 & 97
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Measurement of compartment pressures is the standard for the diagnosis of compartment syndrome.
Methodology
Various methods, as well as equipment, are available for this purpose. A transducer connected to a catheter usually is introduced into the compartment to be measured. This method is the most accurate method for measuring compartment pressure and diagnosing compartment syndrome. Measurement of the compartment pressure then can be performed at rest, as well as during and after exercise.
With acute syndrome, the exact threshold is controversial, but typical ranges are from 30-45 mm Hg at rest. Some sources state that it is better to associate this pressure to diastolic pressure (i.e., within 10-30 mm Hg of diastolic pressure).
With chronic compartment syndrome, resting intracompartmental pressure above 15 mm Hg or exertional pressure greater than 30 mm Hg generally is considered elevated. Prolonged elevated pressures of more than 20 mm Hg for 5 minutes or more after completion of exercise is also considered abnormal. (Abraham T Rasul, Jr, MD, Compartment Syndrome, eMedicine)
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Procedural Skills: Use of Ketamine
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Ketamine is a parenteral anesthetic drug with several properties that yields it particularly useful in disaster situations. Because of its unique properties, it has been used in battlefield situations as well as in disaster scenarios where anesthesia had to be provided in the field (e.g., in field amputation secondary to building collapse). It is also an anesthetic choice to be considered in the emergency department.
Within a wide therapeutic range, it provides excellent analgesia and amnesia while supporting respiratory reflexes and spontaneous ventilation. This is a noteworthy quality given the potential of inadequate numbers of ventilators available in a disaster situation. Because of sympathomimetic properties, cardiac function is not depressed nor is there the peripheral vasodilation seen with most anesthetic drugs, making it an ideal choice in the hypotensive patient. It also is a superb bronchodilator.
Ketamine is a dissociative anesthetic and produces an unusual sedative state. The onset of anesthesia occurs in 30-60 seconds given IV, but is considerably longer given IM (20 to 30 minutes or longer). The patient appears catatonic with eyes open, sometimes with nystagmus present. Although brainstem function is maintained, higher cognitive awareness is disconnected from somatic sensory input. Normal or slightly enhanced muscle tone is maintained, and varying degrees of skeletal movement despite analgesia and amnesia is to be expected.
In contrast with most anesthetics, upper airway reflexes remain intact even at induction doses. Sonorous respirations are observed frequently and may be managed by repositioning the patient's head and airway. Stimulation of the vocal cords by instrumentation or secretions may produce mild laryngospasm rarely. Brief apnea may occur when ketamine is administered via rapid intravenous push. Laryngospasm is rare and usually responds to brief gentle positive pressure ventilation with a bag-valve-mask device. Mild upper airway obstruction secondary to the tongue is more common, and this usually responds to repositioning of the patient's head or a jaw thrust. Although ventilatory drive is maintained, supplemental oxygen should be administered.
In addition to the catatonic state and intermittent motor activity, other side effects include increased salivation, which may be blunted with pre-treatment with an antisialagogue. Intracranial pressure is also increased, and so it is not the ideal drug for a head-injured patient. In adult patients, there is also a frequent emergence phenomenon during recovery characterized by hallucinations and terrifying dreams. This reaction can be ameliorated with benzodiazepines, although this may prolong recovery times due to sedation. A quiet and calm environment during recovery will decrease the incidence of the emergence reaction. This is not seen in patients less than 10 years of age.
Dosing
usual induction dose is 1-2 mg/kg IV or 4-8 mg/kg IM (additional drug may be necessary)
IV dosing is preferred, more reliable, and more readily titratable
analgesia can be attained with lower doses
effects last approximately one hour
may be maintained with additional boluses of .5-1mg/kg IV or 2mg/kg IM
may instead use an infusion of 200mg ketamine in NS 50cc at .5cc/kg/hr; stop infusion 15 minutes prior to end of procedure
consider glycopyrrolate .01 to .02 mg/kg (not to exceed .2 mg) or atropine .01 mg/kg (not to exceed .5 mg) as premedication to decrease secretions
supplemental oxygen, cardiac monitoring, and pulse oximetry should be provided
small doses (as little as 10mg IV) can provide limited analgesia, and have been successfully used especially as an adjunct to narcotic administration
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Procedural Skills: Faciotomies
#98
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Methodology
provide adequate analgesia and anesthesia
pre-operative broad spectrum antibiotics
ensure ALL compartments in extremity checked for pressures (multiple compartments may be affected)
check compartment pressures before and after fasciotomy
ensure adequate hemostasis
pack wound open and use large bulky dressings
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Objective
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Describe the treatment of an entrapped patient.
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Entrapped Patient: Treatment
#99
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fluid resuscitation before victim extricated
1 L NS bolus, followed by 1-1.5 L per hour infusion
limb stabilization
minimize potential systemic effects of reperfusion
consider use of tourniquets prior to release
consider alkalinization by giving 1 ampule of sodium bicarbonate (50 meq) immediately prior to extrication, followed by adding 1 ampule of sodium bicarbonate to each liter of NS infused at 1-1.5 L per hour as above; keep second IV line open without sodium bicarbonate.
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Objective
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Describe the indications (potential need) for field amputation.
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Indications: Field Amputation
#100,101,102
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The context may dictate the need for field amputation. Indications would include the inability to safely extricate the patient, continued environmental toxins that pose a hazard to victims or rescuers, and a grossly prolonged time until definitive treatment is available even after extrication.
Field amputations are best performed by trauma or orthopedic surgeons. Few EMS systems have amputation protocols. If a field amputation is performed, ensure adequate analgesia and anesthesia. Ketamine, a dissociative anesthestic that does not cause cardiorespiratory depression, decreases or only minimally increases serum potassium levels.
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Objective
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Describe the military experience in blast injury care, such as hemorrhage control issues and issues related to the use of tourniquets.
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