A 25-year-old otherwise healthy male was involved in a motorcycle accident resulting in multiple long bone and pelvic fractures, and blood in his pelvis and abdomen. Massive blood loss occurred in the operating room, and the patient was rapidly transfused with 15 units of packed red blood cells (pRBC), 12 units of fresh frozen plasma (FFP), and two 6-packs of platelets. Despite the fluid resuscitation, the patient remained hypotensive. The astute resident in the case noted that the ionized calcium level on the last arterial blood gas was low and promptly administered 1 g of intravenous calcium chloride. The blood pressure rapidly improved. Why was the patient’s calcium low? Why did treating the hypocalcemia improve the blood pressure?

A 27-year-old female, G1P0 at 39 weeks gestational age, is currently receiving a magnesium sulfate infusion for pre-eclampsia. You are consulted for a possible cesarean section. You begin to interview her and notice that she is lethargic and has a hard time staying awake. You promptly check her deep tendon reflexes and notice that they are hyporeflexic. You immediately notify the obstetrician of your findings. What are the next steps you should take? What are your concerns? How would this affect your anesthetic management of this patient?

A 32-year-old male with a spinal cord injury (SCI) at the level of T4 from a motor vehicle accident nine months ago presents for a pre-surgical anesthesia evaluation. He will be undergoing a lithotripsy for bladder stones. He has no sensation below the level of T4. Apart from the SCI, he has no other medical problems. What are your considerations for this patient? If this patient has autonomic dysreflexia, how would this change your anesthetic plan?