Deck 3 Flashcards
Fat embolism definition
Circulating fat globules in circulation and pulmonary parencgyma
Triad of fat embolism syndrome
Respiratory insufficiency: Increased RR, SOB, cyanosis
Cerebral features: drowsiness, rigidity
Petechial rash: sternum, axilla, mouth
Causes of fat embolism
Traumatic:
- fractures
- Hip/knee arthroplasty
Non-traumatic:
- pancreatitis
- liposuction
- bone marrow transplant
Mechanical theory of fat embolism pathophysiology
Fracture leads to damage to vasculature at that site
Fat globules enter circulation and taken to pulmonary circulation causing damage
They gain access to systemic circulation via arterio-venous shunts and cause ischaemia by obstructing various vessels
Biochemical theory of fat embolism pathophysiology
Stress hormones such as steroids and catecholamines release activated lipase
Free fatty acids increase vascular permeability and induce pulmonary damage
Different forms of fat embolism
Subclinical: minor haematological change, decreased PaO2, no resp distress
Non fulminant (subacute): triad, resolves after 72hrs
Fulminant: resp failure, altered mental state, death
CXR appearance of fat embolous
Snow storm appearance
bilat fluffy infiltrates
Which brain imaging to use for fat embolism
T2 weighted MRI shows high intensity areas within white matter
CT has limited use, may display minimal cerebral oedema
Which brain imaging to use for fat embolism
T2 weighted MRI shows high intensity areas within white matter
CT has limited use, may display minimal cerebral oedema
Causes of enterocutaneous fistula
Abdo surgery 75%
Inflammation: Crohns or infection
Classification of fistulas by output
Low output<200ml/day
Moderate 200-500
High output >500ml//day
Fistula mx
SNAP
Sepsis: abx + drainage
Nutrition: Decompression + TPN to allow healing (In high output fistulas)
Adequate fluid and electrolyte
Plan and protect: conservative vs surgical, protect skin
Which fistulas could be treated conservatively
- no obstruction or sepsis
- not complicated with IBD
Imaging for fistulas
CT with oral contrast or contrast injected through the fistula
MRI used for complex anal fistulation
Complications of TPN
Metabolic:
- K, Mg, phosphate
- glucose (most common)
Line related:
- as per Central line
Rule of 2/3 for portal HTN
2/3 cirrhosis gets portal HTN
2/3 of protal HTN develop oesophageal varices
2/3 oesophageal varics present with acute bleeding
Rule of 2/3 for portal HTN
2/3 cirrhosis gets portal HTN
2/3 of protal HTN develop oesophageal varices
2/3 oesophageal varics present with acute bleeding
Sites of porto-sysyemic anastomosis
Umbilical Upper anal Varices Bare area of liver Retroperitoneal
TIPS procedure
Transjugular intrahepatic portosystemic shunt
Hepatic vein cannulated via IJV
Stent inserted between hepatic vein and branch of portal vein to reduce portal pressure
Complication of TIPS
Encephalopathy as portal blood diverted from liver
Occlusion
False localising sign
Weakness on lateral gaze
Due to brain herniation and its impact on CN6 (long intra-cranial path)
Classical presentation of extra dural haemorrhage
Concussion
Lucid period (conscious): haematoma expanding
Loss of consciousness: ICP increases as per Monro-Kellie
doctorine
Secondary brain injury definition
Any injury that occurs hours or days after primary injury
Due to cellular damage
Prevention of secondary brain injury
- Rapid sequence intubation to keep sedation and control ventilation (hyperventilate pt)
- nurse at 45 degrees (reduces oedema)
- Central line to monitor ICP -> hypertonic saline, mannitol, dex
