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IN A NUTSHELL

The hospital, especially the OR staff, should be prepared to

deal with a patient who suffers from latex sensitivity. Latex-
sensitive patients undergoing surgery should be scheduled as

Cecilia Pascual-Garrido, MD
the first case of the day, when aerosolized latex particles are
University of Colorado, Denver, CO, USA
at a low. If unmanaged, latex allergies can have a profound

and unnecessary impact on hospital resources due to post-
operative complications or operating room teardown costs. If
latex gloves are worn even during the set-up of the O.R., a

last minute discovery of a patient’s latex allergy will require a
teardown of the O.R. set up which would result in significant

What is “PEEK”?
cost implications. Many hospitals are now implementing latex-
free environment in order to avoid these unpredictable issues.

PEEK (Polyetheretherketone) is a strong thermoplastic What is “the process of allograft
polymer (plastic). The properties of PEEK make it an ideal
material for use in orthopedic implants. It closely matches the irradiation”?

mechanical properties of the bone (tensile yield strength, shear
strength and modulus). Clinically, is highly biocompatible (no Allograft irradiation is part of the secondary sterilization
normally used during allograft tissue processing.
cytotoxicity has been observed when implanted) and stays as
a permanent implant with ability to be revised easily.
Sterilization has been defined as the process or act of

PEEK material was initially used in Orthopedics for Spine inactivating or killing all forms of life, especially microorganisms.
implants. Lately, its application has widely spread in the field Sterilization by gamma irradiation is normally used in order

of Sports Medicine in the form of Suture anchors and screws. to minimize the risk of blood-borne diseases transmission
Compared to bioabsorbable suture anchors such as: PLAA such as hepatitis, bacterial or fungal infection, and HIV. The
virucidal and bactericidal effects of gamma irradiation are
and PGA, PEEK is non-absorbable. It offers the advantage
of excellent postoperative imaging (similar to bioabsorbable created by two mechanisms. The primary mechanism is direct
alteration of nucleic acids leading to genome dysfunction and
anchors) with stable fixation without the complication
associated with the degradation of the polymer. No published destruction. A secondary mechanism is the generation of free
radicals, primarily from liquid water.
data to date have been reported on complications or failures
with implants manufactured with PEEK
Initially, human tissue allografts were irradiated with 2.5 to 5
Mrad (25-50kGy), considered as “high dose radiation”, which
What is “sensitivity to latex”?
compromised graft structural integrity and resulted in high
failures rate. More recent secondary sterilization protocols
Latex allergy is defined as a previous reaction to latex. If rash
or other symptoms after contact with latex were developed, have employed lower irradiation doses, typically from 1 to
1.8 Mrad (10-18kGy), and are frequently termed “low dose
that will be considered as a latex sensitivity. Latex allergies radiation”.. Studies conducted on low-dose irradiated allograft
or sensitivity may cause reactions ranging in severity from
suggest that the pre-implantation biomechanical properties
skin redness or a rash to sneezing or even anaphylaxis, a are not altered when allografts are irradiated at these lower
potentially life-threatening condition.
levels.
It is estimated that 6% of the general population suffers from Gamma irradiation is very effective against bacteria at doses
latex allergy and 15% of health-care workers. Patients with
of 1.5 to 2.5 Mrad.
spina bifida (myelomeningocele) are at the highest risk of latex However, gamma irradiation is much less effective against
allergy because of repeated exposure of mucous membranes
viruses. Some studies, have estimated that more than 3.6
to latex during surgeries and procedures. The prevalence of Mrad may be needed to inactivate all but 1 in 1,000,000 HIV-
latex allergy in these patients range from 20 to 67% and their
risk of anaphylaxis in the operating room is 500 times higher infected cells.
Gamma radiation, together with aseptic harvesting, antibiotic
than rest of the population. The prevalence of anaphylactic
reactions during the perioperative period and during medical soaks, multiple cultures, and low-dose gamma irradiation
(<3.0 Mrad), has become the most commonly used process
procedures overall has been defined poorly. Different reports
have suggested an incidence between 1 in 10.000 to 1 in for producing a sterile graft. Despite the risk of HIV infection
from allogeneic grafts, there has been only one reported
20.000.
case in which HIV was proved to be transferred from an
Between 1988 and 1992, the FDA received more than 1000 infected donor.
reports of latex allergic reactions. Most of the cases were
associated with use of gloves or latex balloon-tipped barium Any surgeon using allografts should make a point of being
familiar with the exact techniques and standards used by the
enema catheters. Fifteen deaths occurred, all of which were
related to the use of the latex balloon-tipped catheter. The bank supplying the grafts. Surgeons should feel comfortable
that everything reasonable has been done to ensure that the
deaths prompted the CDC and the FDA to issue a medical grafts they use are of the highest quality available.
alert and recall these products.

ISAKOS NEWSLETTER 2013: Volume II 45