Safety and Effectiveness of Novel Nitroglycerin Based Catheter Lock Solution

Inclusion Criteria: * Inpatients who have a long term central venous catheter (CVC)-and the CVC has been in place for at least 14 days and is expected to remain in place at least for 30 days after enrollment * The CVC consists of a 5.0 French size, dual-lumen, peripherally inserted central catheter * Patients who are willing and capable to provide Informed Consent * Patients who are willing and capable to follow the instructions required to complete the study * Females (of child bearing potential) and males (of child bearing potential) must be abstinent or agree to use birth control during the study. Exclusion Criteria: * Patients who have an antimicrobial CVC. * Patients who have a short term CVC that have been placed in ICU (mainly rigid wall CVCs placed for acute care in ICU). * Patients who are hypotensive with a systolic blood pressure reading of \<110 mmHg at any time over the 3 days prior to study entry * Patients who are not awake, not alert, or who cannot express pain or discomfort related to the catheter locks * Patients with an existing local or systemic infection as defined by evidence of fever (a body temperature \> 38.0o C with two readings taken at least 10 minutes apart or one body temperature \> 38.3o) and any of the following within 24 hours of enrollment: Pulse rate \> 100 beats/min.; Respiratory rate \> 20/min.; WBC count \>12,000/mm3, \<4,000/mm3 or differential count showing \>10% band forms. Patient will still be eligible for the study if the partici…