Biomedical Engineering Reference
In-Depth Information
Table 6.7
Biosynthetic Dressings
Classifi cation
Composition
Examples
Transmits oxygen
Polyurethane fi lms
Polyurethane
or
co-polyester with
adhesive backing
Op-Site Bioclusive, Oprafl ex,
Unifl ex, Blisterfi lm, Visulin,
Ensure, Clingfi lm, Viofi lm,
Acuderm, Omniderm, Dermafi lm,
Silon II, Tegaderm
Fluid retention may be problem
Diffi cult to handle
Omniderm or Silon II better suited
for exudative wounds
Hydrocolloids
Hydrophilic colloidal particles
bound to polyurethane foam
DuoDerm, Actiderm, Tegasorb,
Cutinova Hydro, Ultec, Comfeel
Ulcus, Restore, Hydrapad,
Granulfex E, Intrasite, Intact,
Flexzan
Hydrogels
60-99% water cross-linked polymer,
such as polyethylene or polyvinyl
Vigilon, Second Skin, Biofi lm,
Geliperm, Cutinova Gel,
Elasto-Gel, Intrasite Gel,
Span Gel, ClearSite
Gel formed by dressing often
purulent in appearance and
acrid in odor
If a wound is very exudative, gel will
leak beyond dressing
Calcium alginate
Composite of fi bers from calcium
alginate
Sorbsan
Capable of signifi cant fl uid
absorption
Foams
Hydrophilic or hydrophobic
polyurethane or gel fi lm
Kaltostat
Require frequent dressing change
Signifi cant hemostatic properties
Others
Biobrane
Silicone rubber with nylon and
porcine collagen bilaminate
Cutinova Plus Ulcer Care, Lyofoam,
Sythaderm Allevin, Epigard
Very high absorbency
Similar to hydrogels
N-Terface
Monofi lament plastic
Can become incorporated in wound
if wound dries
May delay reepithelialization
Cellophane wrap
(contains 65%
glycerin)
Cellulose with glycerin
Saran Wrap
Excessive fl uid accumulation occurs
Wick effect transfers fl uids to outer
membrane
Oxygen transmission increases
1000-fold when material is wet
complications of co
2
laser resurfacing
As with all resurfacing procedures, the incidence of complica-
tions is related to both the depth of resurfacing and the
patient's preexisting skin pigment type. Complications include
infection, pigmentary changes, acne and milia, scarring, and
ectropion. Swelling, erythema, petechiae, and itching are nor-
mal postoperative sequelae that may be more prominent in
some patients (120).
preparations such as Theraplex emollient, Cetaphil moistur-
izer (Galderma Laboratories, Inc., Fort Worth, Texas, USA),
Norwegian Formula emulsion (Neutrogena), and Curel
(Bausch and Lomb, Inc., Rochester, New York, USA) are pre-
ferred during this phase. Biologic agents, such as vitamin C,
essential fatty acids, hyaluronic acid, aloe vera, and topical
photoprotective antioxidants such as green tea extract, ideben-
one, or ferulic acid, may be benefi cial in this phase. After the
second week, a lighter, high-moisture cream containing these
biologic agents can be used and continued. Preoperative topi-
cal agents are restarted at 2-3 weeks postoperatively.
To minimize postoperative erythema, we use 0.1% fl uocino-
lone ointment (Synalar®, Medicis, Scottsdale, Arizona, USA)
applied to the face at night from postoperative day 5-21. We
have not noted any decrease in wound healing or allergic reac-
tions as this topical steroid ointment does not contain any
preservatives or stabilizers. In addition, the addition of a topi-
cal steroid decreases postoperative pruritus and edema. Aqua-
nil HC lotion (Person & Covey, Glendale, California, USA)
is recommended for daytime use during the same period.
This mild topical steroid is in a light, moisturizing, non-
sensitizing base.
Close surveillance of patients during the postoperative period
is important to provide emotional support and to detect abnor-
malities in the healing process at the earliest manifestation. Ide-
ally, patients are seen 1 day, 3 days, 1 week, 3 weeks, 6 weeks,
3 months, 6 months, and 1 year postoperatively.
Postoperative Swelling
Postoperative swelling is generally mild to moderate, peaking
on day 2-3 and most often resolving by day 5-7. At times,
however, dramatic swelling may occur that is frightening and
uncomfortable for the patient. Although we do not routinely
use steroids in the postoperative course, in this situation of
excessive swelling, IM Celestone® (6-9 mg) or oral prednisone
(40-60 mg daily for 3-5 days) may be valuable. Patients are
also advised to soak their face frequently and use ice packs or
frozen peas as frequently as needed.
Erythema
Erythema occurs to some degree in all patients and refl ects the
increased blood fl ow and angiogenesis associated with dermal
healing. The degree and persistence of erythema relate to the
depth of resurfacing performed and the amount of nonspe-
cifi c thermal injury produced, as well as to unidentifi ed indi-
vidual variables and possibly to preoperative and postoperative
