Sedation is described as a continuum, and it is often categorized according to the patient's level of consciousness as minimal, moderate, and deep sedation. Intravenous sedation can potentially cause numerous complications. The clinicians should therefore have a thorough knowledge of these possible complications and understand their management strategies. There are several scoring systems used to document the patient's mental status and depth of sedation, such as the Richmond Agitation-Sedation Scale (RASS) and the Inova Health System Sedation Scale (ISS). Prevention of complications starts with a thorough pre-procedural patient assessment. This chapter discusses, among other things, some of the patient-related risk factors and procedure-related risk factors. Among all the complications induced by intravenous sedation, respiratory complications are the most common. Moderate and deep sedation may have varying degrees of depressive effects on cardiovascular function, depending on the patient's physiological status and the dosage of sedatives administered.