(venous access device) surgically implanted.
  Ports and catheters are implanted under
  local anesthetic in an operating room,
  although general anesthetic may sometimes
  be used.
      A port is essentially a small chamber
  placed under the skin, usually near the
  shoulder. The chamber connects to a small
  tube inserted in a vein and threaded through
  it into larger veins.  Access to the port is
  easy for the person injecting the drug and
  avoids the pain and discomfort often
  associated with intravenous injections.