Biomedical Engineering Reference
In-Depth Information
in delivery of analgesics for continuous therapeutic effects at homes. Many
syringe infusers rely on mechanical means (spring-loaded) or operate
electronically to deliver a precise dose over a predetermined time period
(Rapsilber and Camp-Sorrell, 1995). An example of syringe infusers is the
Microfuse
®
syringe infuser (Baxa Corporation, USA) which delivers volumes
between 5 and 140 ml in 20 to 120 minutes.
2.6. Infusion Pumps
Infusion pumps operate by forcing precise parenteral doses to the patient
using either piston-valve pumps or peristaltic pumps. Infusion pumps can be
used in hospitals or at homes, depending on their design. They are commonly
used for parenteral delivery of antibiotics, analgesics, total parenteral nutrition
(TPN) and chemotherapeutic agents (Rapsilber and Camp-Sorrell, 1995).
Peristaltic pumps operate by employing appendages having wave-like
movements with a stationary appendage underneath to prevent backflow of the
medical fluid (Rapsilber and Camp-Sorrell, 1995). Alternatively, a cam within
a cylinder is employed to push the fluid. For further details about peristaltic
pumps,
a
review
by
Rapsilber
and
Camp-Sorrell
(1995)
is
highly
recommended.
2.7. Elastomeric Pumps
Elastomeric pumps, also called balloon pumps, consist of membranes that
permeate the medication fluid when a positive pressure on the fluid is applied
(i.e. when the main chamber is full). Fill volume is up to 0.5 L and can be
delivered over several hours (Rapsilber and Camp-Sorrell, 1995). Recent
research has demonstrated the significant potential of elastomeric pumps in the
control of pain after surgical operations (Boada et al., 2002; Barreiro et al.,
2005; Ansaloni et al., 2007)
3.
D
EVICES
U
SED IN
P
ULMONARY
D
RUG
D
ELIVERY
Pulmonary drug delivery or delivery of drugs to the lungs may offer
significant therapeutic advantages over the invasive means of drug delivery
(i.e. parenteral injections). Pulmonary delivery is achieved using inhalation
