The aim is to achieve a systolic blood pressure of 90 mmHg in order to maintain tissue perfusion without inducing re-bleeding from recently clotted vessels. Permissive hypotension is a means of restricting fluid administration until hemorrhage is controlled while accepting a short period of suboptimal end-organ perfusion. Studies regarding permissive hypotension have yielded conflicting results and must take into account type of injury (penetrating versus blunt), the likelihood of intracranial injury, the severity of the injury, as well as proximity to a trauma center and definitive hemorrhage control.The quantity, type of fluids to be used, and endpoints of resuscitation remain topics of much study and debate. For crystalloid resuscitation, normal saline and lactated ringers are the most commonly used fluids. Normal saline has the drawback of causing a non-anion gap hyperchloremic metabolic acidosis due to the high chloride content, while lactated ringers can cause a metabolic alkalosis as lactate metabolism regenerates into bicarbonate.Recent trends in damage control resuscitation focus on "hemostatic resuscitation" which pushes for early use of blood products rather than an abundance of crystalloids in order to minimize the metabolic derangement, resuscitation-induced coagulopathy, and the hemodilution that occurs with crystalloid resuscitation. The end goal of resuscitation and the ratios of blood products remain at the center of much study and debate. A recent study has shown no significant difference in mortality at 24 hours or 30 days between ratios of 1:1:1 and 1:1:2 of plasma to platelets to packed RBCs.
Microvasculitis refers to a range of diseases or presentations associated with a disease, where there is inflammation of small blood vessels:

Kawasaki disease
Susac syndrome

Nerve microvasculitis
Non-systemic vasculitic neuropathy (NSVN)
Hepatitis C-related cryoglobulinemia neuropathy (CRYOVASC)
Hepatitis B-associated PAN
Diabetic lumbosacral radiculoplexus neuropathy (DLRPN)
Non-diabetic lumbosacral radiculoplexus neuropathy (LRPN)
Diabetic cervical-radiculoplexus neuropathy (DCRPN)
Diabetic Cranio-Cervico-Radiculoplexus Neuropathy
Diabetic Cervical Neuropathy


== References ==