History 

Sample history for crush/traumatic ischemia is shown below:

"Peggy S. is a 26 y/o woman who was involved in an auto/pedestrian accident earlier this morning. She had a work truck malfunction along the highway. A second work truck was parked in front of her and offering assistance. She was standing on one leg with the other raised up to the bumper of her work truck. A 16 y/o driver in a car was distracted and crashed into the rear of Peggy's work truck at 50 mph. The ensuing destruction pinned Peggy's left leg between the two trucks. She was extricated and taken to the University Level 1 trauma center. Both orthopedic and vascular surgeons took her to the operating room the begin the process of saving her left leg. 

Plain X-Ray and CT scan of the left leg revealed a compound, comminuted fracture of both tibia and fibula of the left leg. The tibial plateau of the left leg is shattered with a short section of tibia remaining. Should reconstruction fail, this short section of tibia and a shattered tibial plateau is unlikely to support a below knee amputation. Hence, should limb salvage fail, an above the knee amputation will be required. 

In the operating room, the vascular supply at the trifurcation was disrupted requiring emergency bypass surgery and arterial repair by the vascular surgeons. This makes her trauma a Gustilo IIIC trauma score with a 50% likelihood of permanent injury and complications. 

Her pertinent past history includes treated depression and body image disorder. 

We have been asked to see Peggy and to provide hyperbaric oxygen therapy as an adjunctive therapy to assist limb salvage and healing her multiple fractures. We are happy to do so with a diagnosis of crush injury to the left lower leg."

[Note that compartment syndrome would be a similar history of closed leg crush, fracture, or injury with resultant impending/established compartment syndrome. Brief sample:

"John T. is a 36 y/o man with short history of work injury this evening. A 400 pound piece of steel fell and trapped his right leg between the steel and bench. He did not sustain any fractures but came to the emergency room with a tight, swollen right leg below the knee. The emergency room physician measured compartment pressures using ultrasound and needle measurements. Pressures were at least 30mmHg higher than diastolic pressure in each compartment. He has been taken to the operating room for emergent compartment releases. 

In the operating room, the surgeon noted that several muscles were hypoxic and dying. When stimulated by the electrical cautery, there was no muscle movement. Because of this finding, the surgeon asked us to provide hyperbaric oxygen in adjunctive fashion to attempt limb/muscle salvage. We will start therapy this evening with a diagnosis of acute, established compartment syndrome of the right lower leg."

Physical Exam

Acute traumatic peripheral ischemia

"Hard" signs of arterial injury: 

• Active hemorrhage
• Expanding or pulsatile hematoma
• Arterial vibration upon palpation
• Bruit near or over the artery upon auscultation
• Six Ps of acute ischemia: pain, pallor, poikilothermia, pulselessness, paresthesia, and paralysis

Crush injury

• Typically presents with involvement of multiple tissues (skin, subcutaneous tissue, muscles, bones, nerves, vessels)

Skeletal muscle compartment syndrome

• History of severe trauma, especially involving crush injuries or fractures of long bones of the arm or leg
• Pain levels disproportionate to apparent injury
• Tense muscle compartment, painful to passive extension of affected limb
• Increased measured intra-compartmental pressure (not required for diagnosis)

5 P's:

• Pallor, paresthesias, pulse deficit, paralysis, and pain on passive extension of the compartment 
• Pain is usually very severe and occurs early
• Paresthesias may occur early as well
• Paralysis is a late sign
• Pulse loss is a late sign

Impression

• Acute Traumatic Peripheral Ischemia Refer to ICD-10 Crosswalk
• Crush Injury Refer to ICD-10 Crosswalk
• Compartment Syndrome Refer to ICD-10 Crosswalk

Plan

A typical hyperbaric regimen for a traumatic ischemia consists of an aggressive treatment protocol. Patients will be treated at 2.0 or 2.4 ATA with oxygen breathing from 90 minutes. Initially, treatment will be twice daily. Once the extremity is stable and the neurovascular status is improved, treatments will be once daily for several days. If the tissue begins to show evidence of advancing ischemia or progression of tissue destruction, the twice daily regimen can be extended or renewed.

Risk and Benefit of Hyperbaric Oxygen Therapy 

• Please refer to topic "Documentation HBO: Risks and Benefits"
  

Indication for Hyperbaric Oxygen Therapy (HBOT)

"Acute traumatic ischemia occurs when there is a severe injury to a limb that results in compromise of the arterial blood supply or perfusion differential pressure to that limb. The immediate, emergent threat is determined by whether perfusion of the limb is sufficient to maintain viability of the tissues. Crush injuries are directly associated with trauma while skeletal muscle compartment syndromes arise from ischemia, venous outflow obstruction, exertion, external compression, or trauma. There are 3 common features: 1) ischemia and hypoxia at the injury site, 2) a gradient of injury, and 3) the potential for self-perpetuation of the injury. 

While hyperbaric oxygen is a useful adjunct, surgery and aggressive medical interventions will often be required in order to manage the condition. Conditions with related pathophysiology, which are also amenable to hyperbaric oxygen therapy, include threatened flaps, grafts, re-implantations, and frostbite. The pathophysiology is a picture of vasogenic edema as a consequence of injury exacerbated by cytogenic edema because the injured tissues are no longer able to maintain intracellular water. When tissue oxygen tensions fall below 30 mmHg, the host responses to infection and ischemia are compromised. White blood cell phagocytic killing becomes ineffective, fibroblasts are no longer able to secrete collagen, and neovascularization cannot occur. 

Hyperbaric oxygen (at 2 ATA) increases blood oxygen content by 125%, where plasma and tissue oxygen tensions are increased by 1000%. Hyperbaric oxygen also induces vasoconstriction (decreasing blood flow by 20%), thus reducing edema. In this indication, hyperbaric oxygen enhances oxygen concentration at the tissue level, increases oxygen delivery per unit of blood flow, and reduces edema."

Sample Order

•  See Sample Physician Order - Acute Traumatic Peripheral Ischemia
•  See Sample Physician Order - Crush Injury/ Compartment Syndrome

CLINICAL EVIDENCE AND RECOMMENDATIONS

Hyperbaric Oxygen Therapy for Crush Injuries and Acute Traumatic Ischemia

• 1BFor patients with crush injuries and acute traumatic ischemias, adjunctive HBOT is recommended to mitigate resulting tissue damage, preferably within 4-6 hours of the injury. (Grade 1B)
• Rationale: HBOT increases oxygen availability to hypoxic tissues during the immediate post-injury period and increases tissue oxygen tension needed to support host response to trauma.[6][7] Use of adjunct HBOT for this indication is backed by moderate certainty evidence (level B), drawn from a positive randomized controlled trial (RCT) and over 600 case reports in more than 20 publications.[2][8][9][10] As one would expect, there is a great deal of variability in these case reports, such as: time from injury to HBOT, mechanism of injury, injury kinetic energy sources, and 'standard care.' We note that the vast majority of these cases improved with adjunctive HBOT. Improvements were more dramatic when HBOT was introduced early on after the injury, and injuries responded better when more than one HBOT treatment was undertaken in the first few days post-injury.
• For optimal results, HBOT should be initiated in those crush injuries where complications (e.g. flap necrosis, osteomyelitis) are predictable but not yet established, such as fractures Gustilo III-B and C, or lower Gustilo grades if the patient is impaired/decompensated.[6] However, we need to note that, on many occasions in daily clinical practice, clinicians are asked to provide HBOT for injuries that have already started to fail or other serious complications have appeared. Even then, the evidence will support the use of HBOT and encourage earlier intervention whenever possible.
• Coverage: Medicare covers adjunct HBOT for crush injuries and acute traumatic ischemia on an outpatient basis, but not for hospitalized patients.[1]

Hyperbaric Oxygen Therapy for Skeletal Muscle Compartment Syndromes 

• 1CFor patients with skeletal muscle compartment syndrome (SMCS) in the impending stage (i.e., symptoms of SMCS with no indication for fasciotomy), adjunct HBOT is recommended to prevent progression to the established stage (i.e., SMCS with indication for fasciotomy). (Grade 1C)
• 1CFor patients with SMCS in the established stage, adjunct HBOT is indicated to prevent wound healing complications and promote recovery. (Grade 1C)
• Rationale: HBOT increases oxygen availability to hypoxic tissues during the immediate post-injury period and increases tissue oxygen tension needed to support host response to trauma.[6][7] Use of adjunct HBOT for this indication is backed by low certainty evidence (level C), based on expert opinion, experimental studies and case reports.[6][11][12][13][14][15] There are no RCTs in the area of extremity compartment syndromes. There are however, multiple papers involving case presentations and case series that suggest early intervention with HBOT will be beneficial in preserving muscle in the injured compartment. Benefits of adjunctive HBOT outweigh the risks. Adjunctive HBOT is regarded as the only intervention with the potential to prevent progression of SMCS from the impending to the established stage.[6]  

APPENDIX

Summary of Evidence

Crush Injuries and Acute Traumatic Ischemia

(back to text)

Randomized controlled trial (RCT)

• In 1996 Bouachour et al. published a randomized, controlled, sham, blinded study using HBOT as an adjunctive addition to surgical care.[2] This is a complicated study because of the vagaries of trauma care. The HBOT intervention was 2.5 ATA and administered twice daily for 6 days post-injury. The results show dramatic improvement in the HBOT group (N = 36) and equally divided between sham and intervention groups. Complete healing occurred in 17 of the HBOT group and 10 of the sham. Additional surgical interventions (like skin grafts, vascular surgery, and/or amputation) was undertaken in 1 patient in the HBOT group and 6 in the sham group. The research group documented that regional perfusion indices (affected limb vs. non-affected limb) were consistently 0.9 or greater during HBOT, suggesting that episodic exposure to HBOT and increased oxygen to the injured area improved outcome. 

CATEGORY A CONTINUING EDUCATION CREDIT

This topic has been reviewed and approved by the National Board of Diving and Hyperbaric Medical Technology (NBDHMT) for one (1) Category A Credit.

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• 1. Read the topic
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For more information on Category A continuing education credits see blog post " Hyperbaric Certification and Continuing Education for Technicians & Nurses".

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