The best method to assess the adequacy of replacement of fluid in a case of shock is:

The primary goal in fluid resuscitation for all forms of shock is the same: restoration of adequate end organ perfusion. Urine output is a quantitative and relatively reliable indicator of organ perfusion. It is a reflection of kidney perfusion and function and an indicator of renal, cardiovascular, and fluid volume status. Must know: Signs of a successful initial resuscitation: Improved blood pressure Improving level of consciousness Improving peripheral perfusion Decreasing tachycardia Decreasing lactate Normalizing pH Ref: Holcroft J.W., Anderson J.T., Sena M.J. (2010). Chapter 12. Shock & Acute Pulmonary Failure in Surgical Patients. In G.M. Dohey (Ed), CURRENT Diagnosis & Treatment: