Fat embolism

Definition: 

Fat emboli:

- a complication of trauma/ surgery that involve intrumentation of femoral intramedullary canal

- it is a response/ manisfestation of fat globules that may enter the blood stream

Fat embolism:

- a process by which fat emboli passes the bloodstream and lodges within the blood vessel

Fat embolism syndrome:

- serious manisfestation of fat embolism that causes multi system dysfunction

Causes: 

1. mechanical theory

- fat droplets from bone marrow enters the vessel

- increase of intramedullary pressure and cause fat/marrow to enter the bloodstream. which later could lodge in the lungs as emboli

- causes inflammation and local ischemia

2. metabolic theory

- stress from trauma that causes change to the chylomicron that causes formation of fat emboli

or

1. trauma related

- fracture at long bones: especially femur fractures

2. non trauma related

- liver disease, shock, bone tumor lysis

Symptoms:

- asymptomatic within the first 12-48 hours

Gurd's criteria: 2major 1 minor or 1major 4 minor

• Major: 

- hypoxemia, petechial rashes, neurological symptoms, pulmonary edema

• Minor: 

-tachycardia, fever, retinal changes/ renal changes/ fat macroglobinemia, jaundice, 

- drop in Hb, increase ESR, thrombocytopenia

Investigation: 

- FBC

- ABG

- RP/LFT

- CXR : ground glass appearance / snow storm appearance

Management:

- stabilise the patient

• Airway : no obstruction
• Breathing: oxygen support
• Circulation: two large branulla with fluid support 
• hemodynamically: Hb? any blood loss
• hydration: 3L/d

1. monitor vital signs : BP, PR, SPO2, temperature

2. inform 

- MO incharge, anaest (ventilator support)

- keep in view the need of doing CT brain to exclude other causes

3. rigid fixation of fracture within 24 hours

4. diagnosis of exclusion

5. DVT prophylaxis 

6. stress ulcer prophylaxis

Reference: 

1. https://www.orthobullets.com/basic-science/9055/fat-embolism-syndrome

Compartment syndrome

Definition:

a rise in pressure within a closed osteofascial compartment, resulting in impaired local circulation compartment. 

Causes:

high risk injury:

- fracture that causes inflammation to the muscle where it has no place to expand therefore compressing on the vascular structure and nerves

- operation

- infection

- trauma: crush injury

- burn injury

- tight plaster cast

clinical features

5P s

• PAIN: pt will complain excrutiating pain, just like they wanted to have their legs cut off
• Pallor
• Parasthesia
• Pulselessness
• Paralysis

Passive stretch test: positive 

- can be seen in the video below 2:50 onwards

transducer : to measure the pressure we have at the compartment

Management : 

1. triage

2. if there is a cast or bandage, remove it immediately

**no compression

3. elevate the limb but not above heart treatment

4. emergency fasciotomy

2. Emergency Fasciotomy 

NF and GG

 

Necrotising Fasciitis vs Gangrene

 

** REMEMBER TO ALWAYS DO RESUSCITATION FIRST PRIOR OTHER MANAGEMENT (ABX, ANALGESICS, DM CONTROL)

Indication for amputation: 3D's

🐣 Dying / diseased bone - PVD, infection, gangrene, trauma

🐣 Dangerous - lethal sepsis, malignant

🐣 Damn nuisance - gas gangrene, crush syndrome, severe malformation

Sample Xray

 Gas shadows seen extending from the foot up to upper calf 

Doppler 

Usually medical officer will ask for a doppler done and also ABSI. 

So try to get your doppler right. 

There are three spots that we must check : the Dorsalis Pedis Artery (DPA), Posterior Tibial Artery (PTA) and Brachial 

 

                   Normal ABSI: 1.0-1.3                                                    Normal wave: Triphasic

          ABSI 0.5-0.9: moderate to severe

ABSI >1.3: common in DM (may have severe calcifications)

Antibiotics:

For NF: commonly polymicrobial bacteria can be seen. 

• - IV Tazocin 4.5g QID (consist of piperacillin and tazobactem)
• - IV clindamycin 600-900mg  TDS 
• inhibitor of protein synthesis and protein  m synthesis 
• effective for gram +ve
• or Cefotaxime + metronidazole

 OTHERS:

• - unasyn (beta lactam, inhibiting bacterial cell wall synthesis)
• - ciprofloxacin : covers gram negative

Reference: 

Doppler PDF

Short terms;

- WD: wound debridement

- h/o : history of

- DM : Diabetes Mellitus

- DFU : Diabetes Foot Ulcer

- ABSI : Ankle Brachial Index