This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Anaesthesia
True about Epidural anesthesia – a) Effects start immediatelyb) C/I in coagulopathiesc) Given in subarachnoid spaced) Venous return decreases 
Select and explain. 
A. bd, B. d, C. ab, D. ac
A: bd
Answer: A: bd 
Explanation: Epidural anesthesia is given outside the dura in epidural (extradural) space (not in subarachnoid space).
Onset of effect takes place in 15-30 minutes (not immediately). In contrast, spinal anesthesia has immediate effect (approximately 5 minutes).
Neuraxial block (spinal & epidural) anesthesia is contraindicated in coagulopathy or bleeding diasthesis.
Neuraxial block (spinal & epidural) can cause venous pooling and decreased venous return.