The investigators are testing the hypothesis that administering 2L of body temperature warmed lactated ringer's intravenously prior to surgery can optimize the postoperative and recovery of patients undergoing total hip and total knee arthroplasty.

Hip and knee arthroplasty are safe and reliable surgeries for the majority of patients, but a small percentage experience major complications such as myocardial infarction, deep vein thrombosis (DVT), and pulmonary embolism (PE). As these complications are related to local tissue hypoxemia and patient immobility, interventions that can improve the ability of the heart to deliver blood to the tissue and help patients mobilize earlier in their postoperative course may decrease these complications. Based on recent evidence, it has been shown that many patients are dehydrated before surgery, which can make them feel nauseous, tired, and increase their perception of pain making them less likely to mobilize. This predisposes them to DVTs, pulmonary embolism, nausea and vomiting. Peri-operative dehydration can also decrease the ability of the lungs to oxygenate the blood properly and can place additional stress on the heart, which can increase the risk of heart attacks. The specific aim is to determine if patients' peri-operative hemodynamics can be improved with preoperative administration of 2 L of lactated ringers, and consequently reduce postoperative complications and improve recovery in arthroplasty patients.

Inclusion Criteria:

• All patients >= 18 years of age, undergoing a total primary knee or hip arthroplasty

Exclusion Criteria:

• Patients weighing less than 80 kg.
• Patients undergoing irrigation and debridement, explantation, or revision will not be eligible.
• history of kidney disease, congestive heart failure, pulmonary edema, cirrhosis of the liver, or history of systemic fluid overloard will be excluded from the study.
• No one will be excluded based on gender, ethnicity or race.

90 Days postoperatively