Learning objectives
Learn about pathologic & non-pathologic causes of ectopic gas.
Recognize alarm signs for identification of situations on which ectopic gas detection implies emergency medical conditions.
Understand underlying causes and processes ofectopic gas from a practical approach.
Background
Ectopic gas is defined as presence of gas in abnormal locations.
It constitutes a common radiological finding,
whose clinical significance ranges from "benignant" to "life-threatening" situations.
Answering thefollowing two questions could representa good strategy to assure the best management for each case:
1.
Which is the site of origin?
2.
Does it imply a severe clinical condition? There are certain alarm signs related to clinical severity which radiologists should be familiarized with.
Determination of the origin of the ectopic gas
This is not always an...
Findings and procedure details
Once learned that the presence of ectopic gas can be related to a wide spectrum of clinical situations,
in this section a etiopathogenic approach will be made.
1.
ECTOPIC GAS OF IATROGENIC ORIGIN
TENSION PNEUMOCEPHALUS
Also known as intracraneal aerocele,this entity is characterized by presence of air within the subdural space.
It is considered a neurosurgical emergency due to the mass efect the pneumocephalus provokes against the underlying cerebral parenchyma,
with subsequent permanentneurological damage.
Most of the times it is secondary to an unidirectional valvular...
Conclusion
Presence of gas in abnormal locationsis a common radiological findingrelated to a wide range of clinical situations.
Underlying causes and processes should be understood and certain alarm signs recognized in order to identify thosecases on which ectopic gas implies an emergency medical condition.
References
ATLS: Advanced Thrauma Life Support Guidelines
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Cerebral air embolism...