Anesthetic Course
One hour before entering the operating room, 1,500 units of Confact
F® were transfused. In terms of transfusion volume,
although we planned to carry out implant placement, it was determined
that the amount of bleeding would not differ greatly from that of tooth
extraction alone, so we used 25 IU/kg, basing our calculations on those
published in the New England Journal of Medicine (Table
2).3 Immediately before surgery, we took another blood
sample. We confirmed that VWF activity was 127% and that coagulation
factor VIII had increased to 104%. We then proceeded with the surgery.
Considering that fluctuations in hemodynamics during surgery promote
bleeding, intravenous sedation was performed to stabilize circulation.
Oxygen (2 l/min) was administered transnasally, and cefmetazole sodium
(1 g) was administered preoperatively to prevent infection. During the
operation, we used midazolam iv and propofol (1% Diprivan Injection
kit®) target-controlled infusion for continuous
intravenous sedation. Also, 2% Xylocaine Dental® with
epinephrine 1:80,000 was used for local anesthesia. The operation time
was 3 hours and 37 minutes, the anesthesia time was 4 hours and 16
minutes, and blood loss was 405 ml. Although it was a little difficult
to stop bleeding during the operation, we completed the procedure with
no major problems. No postoperative complications, such as bleeding were
observed, and the prognosis was favorable. One week after the operation,
evaluation of the coagulation factor VIII and VWF activity revealed that
they had decreased to 48% and 23%, respectively, which were close to
their preoperative values (Table 3).
Discussion
VWD is a congenital bleeding disorder inherited in an autosomal dominant
manner. This condition consists of a quantitative or qualitative
abnormality in the VWF, a hemostatic factor that causes a temporary
hemostatic disorder. The VWF functions as an intrinsic coagulation
factor that mediates platelet adhesion to subepithelial connective
tissue and stabilizes binding to coagulation factor VIII.
A lack or decrease in these functions can cause bleeding. Under the
disease classification proposed by the International Society on
Thrombosis and Haemostasis, there are the following types of VWD: 1, 2A,
2B, 2M, 2N, and 3.4 Type 1 is the most common and
features a quantitative deficiency of the VWF but no functional
problems. It was previously reported that desmopressin (DDAVP) is
effective for hemostasis management in mild to moderate hemophilia and
VWD.5 Therefore, DDAVP was used in many cases
considering side effects such as the risk of infection from hepatitis
virus and AIDS. However, the increase in deficiency factor activity is
uncertain. Although it is used for short-term hemostasis, it has limited
application since it cannot be repeatedly or continuously used. The
improved viral inactivation accuracy of Confact F®improves the purity and safety of the drug, and the risk of infection is
said to be lower than before.6 Although in this case,
we planned to perform tooth extraction and implant placement, it was
determined that the amount of bleeding would not differ greatly from
carrying out tooth extraction alone, so for the transfusion volume, we
used 25 IU/kg, basing our calculations on those published in the New
England Journal of Medicine (Table 2). Although no abnormal bleeding was
observed during or after surgery, it was necessary to pay attention to
bleeding when carrying out implant placement. Furthermore, stabilizing
hemodynamics using appropriate analgesia and sedation is also considered
extremely important for reducing the risk of bleeding.
Conclusion
In this case, we carried out safe perioperative management under
intravenous sedation combined with local anesthesia after preoperatively
supplementing with heat-treated factor VIII concentrate (Confact
F®) when extracting teeth and placing implants for a
Type 1 VWD patient. Stabilizing hemodynamics using appropriate analgesia
and sedation is also considered important for reducing the risk of
bleeding.