Biomedical Engineering Reference
In-Depth Information
pathogenetic bacteria that can cause infection. As the studies
described earlier suggest that antibiotic prophylaxis can help
reduce the rate of infection after ablative laser skin resurfacing,
especially when a closed wound care technique is utilized post-
operatively. Furthermore, many authors believe that both
gram-positive and gram-negative antibiotic coverage should
be instituted when occlusive dressings are utilized for wound
care after cutaneous laser skin resurfacing (43,150).
There are some authors, however, who have not found anti-
biotic prophylaxis effective in reducing rates of infection after
cutaneous laser resurfacing. In a retrospective study of 133
consecutive patients undergoing CO
2
laser resurfacing, Walia
et al. found a signifi cantly higher rate of infection in patients
receiving intraoperative (cephalexin 1 g IV) or postoperative
(azithromycin 1.5 g PO for 5 days) antibiotics. The most com-
mon pathogens found were
Pseudomonas
and
Enterobacter
species. The authors concluded that prophylactic antibiotics
are not necessary, especially if good postoperative care is fol-
lowed (151,152).
The literature shows that staphylococcal infection may be
prevented by the prophylactic use of systemic antibiotics such
as dicloxacillin, azithromycin, or ciprofl oxacin (16,45,121).
The use of intranasal mupirocin (Bactroban®) (153), however,
has not proved to be advantageous and may even worsen the
situation. All staphylococcal infections occurred in the group
of patients using intranasal Bactroban in a study of patients
randomly assigned to use or not to use Bactroban for 3 days
preoperatively and 7 days postoperatively (100).
The prevention of bacterial infections should not be taken
lightly, because toxic shock syndrome has been reported after
a benign cutaneous infection with
S
.
aureus
after laser resur-
facing in three patients to date. Also, scarring secondary to dis-
ruption of wound healing has resulted from
S
.
aureus
and
Pseudomonas
infection.
Another postoperative infection that may result from the
moist wound environment is cutaneous candidiasis. This has
been found to correlate with a prior history of vaginal yeast
infection (43). Prophylaxis with a single dose of fl uconazole
(400 mg) on the day of surgery is recommended. To date, we
have not seen a yeast infection occur in a patient who received
this prophylactic treatment preoperatively. The presentation of
this infection postoperatively may include typical signs and
symptoms of cutaneous candidiasis but also may be atypical
and present only as slow wound healing, itching, and erythema.
It should always be suspected in a patient with unexplained
poor wound healing. A potassium hydroxide preparation from
a scraping of a suspicious area or a culture usually confi rms
the diagnosis.
In contrast to the controversial nature of antibacterial pro-
phylaxis, most authors today advocate antiviral prophylaxis
for herpes simplex virus for all patients undergoing full-face or
perioral skin laser resurfacing (42,44,47). Resurfacing laser-
induced epidermal trauma and thermal injury can reactivate
latent labial herpes simplex virus. The de-epithelialized sur-
face left behind after cutaneous laser resurfacing is highly sus-
ceptible to rapid dissemination of the herpes simplex virus.
The incidence of herpetic outbreak in the postoperative period
has been reported in the range of 2-7% (2,16). All patients
should be administered prophylaxis for herpes simplex virus,
because patients with no known prior history of herpes
simplex infection have been noted to develop an acute episode
in the immediate postoperative period (101). Dissemination
over the treatment area with resultant scarring has been
observed to occur in these patients (Fig. 6.32).
Patients should be treated with an antiviral agent such as
valacyclovir (Valtrex®) or famcyclovir (Famvir®) starting a day
or two preoperatively if they have a prior history of herpes
simplex infection or starting on the day of the procedure if no
prior history. This treatment should be continued at least
through the reepithelialization phase of wound healing (an
additional 10 days). An acute treatment dose rather than a
suppressive dose should be used. Valtrex (500 mg twice daily)
and Famvir (250 mg twice daily) provide higher and longer-
lasting blood drug levels than does acyclovir (Zovirax®, 400 mg
four times daily).
(
A
)
(
B
)
(
C
)
Figure 6.32
(
A
) Dissemination of herpes simplex occurred on day 4 postop-
eratively in a patient with no prior history of herpes simplex infection, despite
pretreatment with acyclovir (Zovirax). Valacyclovir (Valtrex) has been found
to be superior as a preventive medication because much higher drug blood
levels are achieved. (
B
) 10 months postoperatively, scarring from infection is
apparent. (
C
) 8 months later, marked improvement has been achieved with
pulsed dye laser treatment of scars.
