What is the legal test for deliberate indifference by a prison official in a case of medical malpractice?

Second, the prison official must have a "sufficiently culpable state of mind." Farmer, 511 U.S. at 834. "In prison-conditions cases that state of mind is one of deliberate indifference to inmate health or safety." Id. (internal quotation marks omitted). "Deliberate indifference is a high legal standard." Toguchi v. Chung, 391 F.3d 1051, 1060 (9th Cir. 2004). Deliberate indifference exists when a prison official "knows of and disregards an excessive risk to inmate health and safety; the official must be both aware of facts from which the inference could be drawn that a substantial risk of serious harm exists, and he must also draw the inference." Farmer, 511 U.S. at 837.