Vitamin K is an organic exogenous compound required by humans for a vital function in clotting. It is a fat-soluble vitamin that is easily depleted and poorly stored, requiring dietary replenishing given that it cannot be synthesized in sufficient quantities to meet the requirements
of humans and higher mammals. Vitamin K actually refers to not one but a group of fat-soluble (lipophilic, hydrophobic) vitamins that share a common methylated naphthoquinone characteristic chemical structure. There are two naturally occurring forms of vitamin K— vitamin K1
and vitamin K2 (Figures 1 and 2). Vitamin K3 is a synthetic water-soluble substance that is chemically similar to natural vitamin K but with limited effectiveness (Figure 3).
Neonatal Network®, established in April 1981, is a peer-reviewed journal dedicated to assisting neonatal nurses and related health care professionals remain current in their fields. Neonatal Network® acts as a vehicle for the exchange of information by providing up-to-date, relevant articles in the areas of evidence-based clinical practice, research, and education. Neonatal Network® is issued six times a year; January/February, March/April, May/June, July/August, September/October, and November/December. With a circulation of 10,000, Neonatal Network® goes to more than 1,000 recognized Level II and Level III neonatal intensive care units in the United States.