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There is a report of general anesthesia for two C/S in one
patient with May-Hegglin abnormality.168 The patient had a low There also are reports of acquired GT whereby patients may
platelet count (approximately 80 ‚ 109/l) and no evidence of present with no previous bleeding history and a normal platelet
bleeding. Spinal anesthesia for C/S was used following platelet count but prolonged bleeding time. Acquired GT is often asso-
transfusion in two other cases.169,170 ciated with lymphoproliferative or autoimmune disorders.181
In one report, a woman with GT received intravenous meper-
idine as neuraxial anesthesia was considered contraindicated.176
Chediak-Higashi syndrome
This is a rare disease, which usually results in death before age In another report, a parturient with GT requiring urgent C/S
ten. It is an autosomal recessive immunological disorder of received general anesthesia as TEG showed poor clot strength
and she had alloimmunization to HLA.180 The woman received
neutrophil function. The syndrome is characterized by partial
oculocutaneous albinism, decreased leukocyte chemotaxis, sus- gamma globulin the night before surgery and then prior to her
ceptibility to infection, and death in childhood. Neurological surgery she received ten units of platelets and recombinant FVIIa.
abnormalities may also occur: in particular, cerebellar involve- Intraoperatively, the woman received 12 units of platelets with
ment, peripheral neuropathies, and mental retardation.174 It is a TEG monitoring before and after administration. She continued
disorder of lysosome fusion and pathognomonic giant granules to receive platelets and recombinant FVII prophylactically post-
are seen in most biochemically active cells. A bleeding disorder partum. Reported operative blood loss was 700“800 ml.
related to platelet dysfunction occurs due to abnormalities of
Platelet storage pool deficiency (SPD)
platelet content and aggregation.
There is one reported case of an uneventful pregnancy and Platelet storage pool deficiency is a heterogeneous group of
vaginal delivery with no mention of anesthesia.175 If there is a disorders that have in common platelets that have decreased
history or evidence of a bleeding disorder, regional anesthesia adenosine diphosphate (ADP) in dense granules and/or decreased
a-granule contents.182 There are three types of platelet storage pool
is contraindicated. These patients are susceptible to recurrent
pulmonary infections, which may be resistant to antibiotic ther- deficiency: those with deficiencies in the dense granules (d SPD),
apy, so strict asepsis is essential. Peripheral neuropathies pro- a- granules (a SPD), or both types of granules (ad SPD). These rare
ducing muscle weakness and wasting may contraindicate the use conditions are transmitted in an autosomal dominant pattern and
of succinylcholine. produce a bleeding diathesis, which may be mild or severe. There
is reduced ADP, ATP, serotonin, and calcium in the dense storage
Glanzmann thrombasthenia (GT) granules of platelets. Hermansky-Pudlak syndrome (HPS) is an
This very rare, life-threatening autosomal recessive bleeding dis- inherited autosomal recessive disorder that manifests as oculocu-
order is characterized by qualitative or quantitative abnormal- taneous albinism, platelet storage pool deficiency (d SPD), and
intralysosomal ceroid lipofuscin accumulation.183 The platelet
ities of the platelet glycoprotein GPIIb and/or GPIIIa complex.
These glycoproteins form a complex in the platelet membrane count is generally normal in this condition although impaired
and act as a receptor for fibrinogen and other adhesive glycopro- platelet aggregation may lead to a hemorrhagic diathesis. Some
teins. Because of abnormalities in binding fibrinogen, severe patients with HPS develop pulmonary fibrosis, which is fatal in the
platelet dysfunction may result with a failure of platelet plug fourth to sixth decades. Grey platelet syndrome (a SPD) is a rare
formation. In vivo, platelets of these patients adhere normally inherited qualitative disorder of platelet function that results in
bleeding.184 The name derives from the grey appearance that is
to the subendothelium of damaged vessels, but there is defective
recruitment of additional platelets via aggregation to form the visible on Wright staining. The platelets are large, have a decreased
hemostatic plug. In vitro, platelets agglutinate normally in the number of cytoplasmic granules (alpha granules), and increased
presence of ristocetin, but do not aggregate in response to other vacuoles resulting in abnormalities of platelet secretion and sec-
platelet agonists (ADP, collagen, thrombin, epinephrine, arachi- ondary aggregation. Thrombocytopenia may also be present.
donic acid).176 There are few reports of pregnancy in women with platelet
There are three types of GT: type I is associated with <5% storage pool deficiency. In one report, there was a family history
normal GPIIb/IIIa; type II has 5“20% normal GPIIb/IIIa; the of bleeding and the patient had a previous hospital admission for
bruising and epistaxis.185 Labor was induced at 39 weeks™ (platelet
variant type has a qualitative defect in the GPIIb/IIIa complex.
count 137 ‚ 109/l) and leukocyte-poor platelets were infused dur-
Few cases of pregnancy have been reported in patients with
this disorder.176,177,178,179,180 Patients with infants suspected of ing and after delivery to prevent hemorrhage. In one case report
having GT are usually delivered by C/S to prevent intracranial of a parturient with HPS, the woman received a platelet trans-
hemorrhage. Women with GT often have multiple antiplatelet fusion during active labor. Intravenous butorphanol was used for
antibodies from previous platelet transfusions.177 Antibody labor analgesia.183



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Chapter 17


Synthetic 1-deamino-8-d-arginine vasopressin (DDAVP) has smear in these syndromes shows hemolysis (schistocytes and
been used in some of these patients to enhance coagulation. If fragmented cells) and thrombocytopenia (see Figure 17.4).
platelet infusions are given, leukocyte-poor preparations should
Preeclampsia and hemolysis, elevated liver enzymes,
be used to decrease antibody development.
and low platelets (HELLP) syndrome
Principles of anesthetic management in parturients with plate-
let storage pool deficiency include avoidance of invasive proce- A small group of patients with preeclampsia develop the HELLP
syndrome.188,189 These patients usually present preterm, although
dures, where possible, and involvement of a hematologist in the
event that the mother is alloimmunized. Regional anesthesia, 30% may present postpartum, with malaise, epigastric or right
including pudendal block, is best avoided. Intravenous narcotic upper-quadrant pain, and nausea/vomiting. Hypertension and
analgesia, nitrous oxide/oxygen in a 50:50 mixture for labor proteinuria are not always prominent features. Hemolysis, ele-
analgesia, and general anesthesia for C/S are the therapies of vated liver enzymes, and low platelets syndrome is associated
choice. Avoid intramuscular injections, aspirin, and NSAIDs. with a high rate of maternal and perinatal mortality and treatment
There is one report of anesthesia in two sisters with grey plate- is delivery of the fetus. In one prospective study, morbidity asso-
let syndrome (GPS).184 The first sister required general anesthesia ciated with HELLP included DIC 18%, abruptio placentae 16%,
for an emergency C/S complicated by severe hemorrhage. The acute renal failure 7.7%, pulmonary edema 6%, subcapsular liver
hematoma 0.9%, and retinal detachment 0.9%.190 Fifty-five per-
second sister had a primary C/S under spinal anesthesia for
oligohydramnios. At that time, the diagnosis of GPS had not cent required transfusion with blood or blood products. Patients
been made in the first sister. Following the diagnosis of GPS the who developed postpartum HELLP had a higher incidence of pul-
monary edema and renal failure.191
second sister had another pregnancy and a repeat C/S following a
The thrombocytopenia may be severe (<20 ‚ 109/l), with the
failed trial of labor. General anesthesia was administered follow-
ing platelet transfusion.184 nadir in platelet count occurring postpartum. Recovery to platelet
counts >100 ‚ 109/l may take up to 11 days.192,193 Providing there
There are reports on the use of intravenous PCA during labor
using remifentanil in parturients with platelet abnormal- is no associated DIC, hemostasis is frequently normal until the
ities.186 Remifentanil has the advantage of a short half-life platelet count is <40 ‚ 109/l.194 However, the platelet count may
and so is unlikely to affect neonatal respiration. However, fall precipitously leading to clinical bleeding in a short period of
interindividual variability and that same short half-life may time. It is essential to assess the course of the thrombocytopenia
make it difficult to balance adequate maternal analgesia with and the clinical picture. If the platelet count has been stable at
80 ‚ 109/l and there is no evidence of bleeding, regional anesthe-
respiratory depression.
sia may be considered. If, however, the platelet count was
120 ‚ 109/l one hour previously and now is 80 ‚ 109/l, regional
Thrombotic microangiopathy in pregnancy
anesthesia may be inappropriate. High-dose steroids have been
and the postpartum period
used to treat preterm HELLP syndrome with a view to improving
The microangiopathic syndromes seen in pregnancy and the the platelet count to a level that will allow the patient to become a
candidate for regional analgesia.195
puerperium are preeclampsia, thrombotic thrombocytopenic
purpura (TTP), hemolytic uremic syndrome (HUS), acute fatty In the past, concern was raised about platelet function in this
liver of pregnancy, and lupus vasculitis.187 The peripheral blood disorder due to studies comparing platelet count and bleeding
time. As these studies found no correlation between bleeding
time and platelet count in HELLP syndrome, regional anesthesia
was considered contraindicated in patients with a platelet count
<100 ‚ 109/l.196,197 Most now agree that the bleeding time is not an
accurate measure of the risk of bleeding. Thromboelastography
(TEG) is being used in some centers in these patients and has
been found a useful technique.198 However, due to the rarity of
an epidural hematoma considerable experience will have to be
gained with TEG to demonstrate its efficacy in determining the
risk of an epidural hematoma in any individual patient. As regional
anesthesia has definite advantages in patients with preeclampsia
(improves intervillous blood flow, avoids potential difficult intuba-
tion), the risks and benefits of the procedure have to be weighed in
each patient with HELLP syndrome.199,200

Thrombotic thrombocytopenic purpura
and hemolytic uremic syndrome
Thrombotic thrombocytopenic purpura and hemolytic uremic
Figure 17.4 A peripheral blood smear from a patient with a microangiopathic
syndrome (HUS) are both characterized by thrombocytopenia,
syndrome demonstrating fragmented cells, schistocytes, and thrombocytopenia.
microangiopathic hemolytic anemia, and ischemia of various
(See color plate section.)



307
5 Other disorders


organs due to platelet aggregation in the arterial microvascula- stabilize a woman with TTP prior to delivery, parturients with
ture.201 Neurological dysfunction is said to be more common with TTP that is active at delivery may have severe thrombocytopenia
TTP while renal dysfunction is more common with HUS, and a significant bleeding diathesis. Regional anesthesia and
although some patients have neither. Although often considered intramuscular injections should be avoided. Due to concerns
as separate disorders, many now consider them to be variants of about neurologic function sedatives should be avoided or used
the same disorder.202 TTP/HUS is a rare disorder (1/100 000) that with caution. These patients are prone to seizures and appropri-
tends to occur primarily in young women, increasing the chance ate precautions should be taken. Platelet transfusions should be
of its concurrence with pregnancy. Although TTP/HUS can occur avoided and packed RBCs and frozen plasma should be adminis-
throughout pregnancy, it occurs most commonly at term (TTP) tered through a large-bore catheter. Patients who have received
and in the postpartum period (HUS). Microangiopathic hemoly- multiple plasma exchanges may have an arteriovenous (AV)
tic anemia and thrombocytopenia are essential to the diagnosis. shunt and this should be managed appropriately. Careful man-
The incidence of TTP in the USA is estimated to be 3.7 cases per agement of intravascular volume and sustaining a good urine
million people and may be increasing.201 The cause is either a output are important to avoid any further renal insult.
deficiency of, or an inhibitor to, VW factor cleaving protease.201 Intravenous PCA or nurse-administered narcotic analgesia,
TTP/HUS probably has multiple pathogenic mechanisms that and nitrous oxide/oxygen are useful techniques for labor analge-
produce thrombi in the microvasculature and/or endothelial sia. For C/S, general anesthesia with special attention to gentle
cell injury.201 Since HELLP syndrome and TTP/HUS share signif- manipulation of the airway is advisable, especially if the platelet
count is less than 50 ‚ 109/l. Hypertension on intubation should
icant clinical and laboratory features it is important to differenti-
ate between the two, as the treatment is vastly different.203 be avoided, if possible, in patients with low platelet counts due to
Hematological manifestations are generally milder in patients the risk of intracranial hemorrhage, as should hypotension due to
with preeclampsia and HELLP in contrast to those with TTP/ potential renal involvement.
HUS. A platelet count <20 ‚ 109/l favors the diagnosis of TTP
Acute fatty liver of pregnancy
providing there is no evidence of DIC. Some report that the
plasma antithrombin III level is reduced in preeclampsia and Acute fatty liver of pregnancy is a relatively rare disease of
normal in TTP.201 The primary treatment of HELLP is delivery unknown etiology, which may present with malaise, nausea,
vomiting, and upper abdominal pain.207,208 There is rapid progres-
and possibly platelet or plasma transfusion. In contrast, continu-
ation of the pregnancy and aggressive treatment of the mother sion over a one to two week period to overt liver failure with
using plasma exchange with frozen plasma is appropriate in jaundice and bleeding. Further deterioration may lead to seizures,
antepartum TTP.203 The use of platelet transfusions in TTP may coma, and death.209,210 Studies of liver function will point to signs
result in a dramatic worsening of the condition from massive of hepatic failure (hypoglycemia, markedly elevated direct biliru-
thrombosis. bin, alanine aminotransferases, blood ammonia, and often rising
Thrombocytopenia in TTP may be severe and in a small num- blood urea nitrogen and creatinine). The peripheral smear is simi-
ber of patients there may be a history of previous episodes. Prior lar to those of other microangiopathic disorders; however, there
to the use of plasma exchange, maternal and fetal mortality were are decreased antithrombin III levels and marked prolongation of
very high.203 Hayward and colleagues reviewed all cases of TTP PT and aPTT, and hypofibrinogenemia. Treatment should consist
in adults at their hospital.204 There were nine treated patients of aggressive support to address the hypoglycemia and coagulo-
of whom one died from ˜˜brain death™™, despite achieving hema- pathy, with careful fluid and electrolyte management, and treat-
ment of associated seizures.208 For anesthetic considerations see
tologic remission. The others had a complete remission of TTP
but most developed long-term complications. One was lost to Chapter 14.
long-term follow-up and of the remaining seven, only one was
completely well. The others suffered mild renal impairment, per-
Miscellaneous platelet disorders
sistent hypertension, persistent memory loss and hemiparesis,
Sticky platelet syndrome
subsequent relapses, optic nerve infarct, and/or persistent myal-
gias and arthralgias.204 Sticky platelet syndrome (SPS) is inherited as an autosomal domi-
Thrombolytic thrombocytopenic purpura may occur postpar- nant disorder and is associated with arterial and venous throm-
tum205 and there also appears to be a familial form of relapsing boembolic disease.211 Clinically, women may have angina, acute
TTP.202 Although TTP may have been successfully treated and in myocardial infarction (MI), transient cerebral ischemic attacks,
remission, it may also recur during pregnancy.202 The overall stroke, and thrombosis in the arterial and venous systems. There
prognosis improves with plasma exchange.203 is one report of a 24-year-old woman who had a MI during her
pregnancy.211 There were no identifiable risk factors except for
her mother who had an acute MI during pregnancy, and an
Management of analgesia/anesthesia
18-year-old brother with angina. Laboratory testing revealed
for TTP/HUS
that her platelets and those of her symptomatic family members
To date, there have been no reports of anesthetic management of were hyperaggregable with ADP and epinephrine. Treatment
the parturient with TTP/HUS. However, there is an excellent of the family resulted in normal platelet aggregation. There was
review of the principles involved.206 Although it is optimal to no information reported regarding the mode of delivery or



308
Chapter 17


10“20% respectively.212 The physiological changes of pregnancy
anesthetic management. However, as platelet aggregation is
normal when these patients are on low-dose aspirin (81 mg), accentuate the AV shunts due to dilation of the systemic vascular
women with SPS should be regarded as normal in regards to bed, increased blood volume, and increased cardiac output while
hormonal changes may weaken the vessel walls.213,214 Reports
their anesthetic management. Other families with venous and
arterial thromboembolism and no other known risk factors have of deterioration of pulmonary AVM during pregnancy indicate
been identified with SPS. that these patients should be followed closely to decrease the
risk of maternal morbidity.215,216,217 In one report, transcatheter
Neonatal alloimmune thrombocytopenia (NAIT) embolic therapy was used in a pregnant woman with pulmonary
AVM.216 Hemothorax has been reported during pregnancy sec-
This disorder is caused by transplacental passage of maternal
ondary to lung involvement,213 and arterial hypoxemia and para-
platelet-specific alloantibodies directed against specific anti-
doxical embolism may reflect pulmonary shunts.216 Congestive
gens present on fetal but not maternal platelets. As a result,
the fetus/neonate may be affected with severe thrombo- cardiac failure due to hepatic AV shunts and portal hypertension
have occurred during pregnancy.218 Fistulas have been reported
cytopenia, which may be associated with massive intracranial
hemorrhage leading to significant morbidity/mortality. Neonatal in the epidural space and in the spinal cord (see Chapter 3).
alloimmune thrombocytopenia is the platelet equivalent of
rhesus (Rh) disease; however, unlike erythroblastosis fetalis,
Pseudoxanthoma elasticum (PXE)
NAIT occurs more commonly in the first pregnancy. The
incidence of neonatal intracranial hemorrhage is 15“20% with Pseudoxanthoma elasticum is an inherited connective tissue dis-
half of these occurring antenatally. Early diagnosis and treat- order with biosynthesis of abnormal collagen and elastin fibers,
ment of the mother with weekly high-dose IVIG from approxi- which may result in hemorrhage and thrombosis. Some authors
question whether PXE deteriorates during pregnancy,219,220,221
mately 20 weeks™ gestation has dramatically improved the fetal
and neonatal mortality and morbidity associated with this although one report suggested that most pregnancies with PXE
are uncomplicated.222 Gastrointestinal hemorrhage may occur
disorder.
Since this disease affects the fetus and not the mother, analge- and there is an increased incidence of cardiac dysrhythmias.
sia/anesthesia for delivery is dependent on the mother™s wishes
and overall clinical condition. However, preparation of compati-
¨
Allergic purpura (Henoch-Schonlein purpura,
ble maternal or homologous platelets is important to ensure their
¨
HSP, Schonlein-Henoch purpura, SHP)
availability for the infant at delivery.
This IgA-mediated vasculitis commonly affects the kidneys,
joints, gastrointestinal system, and the skin and is mainly a dis-
Blood vessel wall disorders
ease of children although several cases have been reported in
pregnancy.223 The clinical syndrome of purpura, hematuria, pro-
Bleeding from disorders of the blood vessel wall is usually mild
and superficial. Inherited blood vessel wall disorders are rare and teinuria, abdominal pain, gastrointestinal bleeding, and arthral-
there is limited information about these patients in pregnancy. gia is due to a generalized vasculitis. It appears to be allergic in
A careful history and, when indicated, a careful assessment, pre- origin but often an etiologic agent is not identified. The effect of
ferably prior to pregnancy or at least well in advance of delivery, pregnancy on HSP is unknown, although one study suggests that
is necessary to fully assess the extent of the disease and its impli- pregnancy may be a trigger for new-onset or recurrence of HSP in
susceptible individuals.224 Plasmapheresis has been used to treat
cations for anesthesiologists. Acquired blood vessel wall dis-
orders are much more common and for the most part fall into severe relapses during pregnancy, resulting in a successful out-
the category of vascular purpura, which arises from damage to the come for mother and fetus.
endothelium or its supporting matrix. There is very little literature
on the anesthetic implications in pregnancy. A careful physical
Anesthetic management of women with
examination to assess the presence of active purpura will provide
vessel wall abnormalities
the best assessment of bleeding risk.
In all of these disorders anesthetic management is dependent
on the status of the patient. There are no specific contraindica-
Hereditary hemorrhagic telangiectasia
tions to regional anesthesia, but if there is ongoing hemorrhage
(HHT, Osler-Weber-Rendu syndrome)
regional anesthesia is contraindicated. In many of these disor-
Hereditary hemorrhagic telangiectasia is inherited as an autoso- ders, abnormal spinal and epidural vessels may be present
mal dominant disease and is characterized by abnormal small increasing the chance of venipuncture with subsequent bleeding
blood vessels and AV fistulae involving almost all organs. The into the epidural space. In each situation, the risk and benefit of
telangiectasia often appear as small blush areas on the skin, and the procedure will determine whether, following appropriate
mucous membrane involvement commonly presents as epistaxis informed consent, regional or general anesthesia should be
or gastrointestinal hemorrhage. Pulmonary arteriovenous mal- used. If regional anesthesia is chosen, these patients should be
formations (AVM) are present in at least 30% of patients with followed closely for possible neurological sequelae. To decrease
HHT, while hepatic and cerebral AVM are present 30% and risk associated with the procedure, the most experienced person



309
5 Other disorders


should perform the block and it should be done in the midline. the fetus will also have dysfibrinogenemia. Women who are
The risks and benefits of the alternatives should be considered asymptomatic may simply be followed closely.
for each patient. In a review of pregnancy in women with congenital dysfibrino-
There is one case report of uneventful epidural anesthesia in a genemia, 55% were asymptomatic, 25% had a bleeding tendency,
laboring parturient with HHT.213 Analgesia, with the subsequent and 20% a thrombotic tendency.232 The prevalence of dysfibrino-
decrease in catecholamines attenuating the increased cardiac genemia in patients with a history of thrombosis is low, 0.8%. In
output from labor, was considered important in decreasing dis- pregnancy, severe bleeding is rare and is usually limited to the
tension of existing AV fistulae. As there is the potential for para- postpartum period. Women with a thrombotic tendency have a
doxical embolism through pulmonary fistulae, the epidural space high incidence of spontaneous abortion and postpartum
should be identified using loss of resistance to saline. thrombosis.
There are two reports of uneventful epidural anesthesia in For the most part the problem with these patients is that of
parturients with PXE.225,226 The major risk during pregnancy is hemorrhage.233,234 Periodic transfusions of fibrinogen may be
related to gastrointestinal hemorrhage, but most reports indicate necessary during pregnancy in order to prevent miscarriage. In
an uneventful labor and delivery. Levitt and Collison reported a patients with evidence of thrombophilia, low-dose heparin may
difficult intubation in a nonpregnant patient with PXE.227 The be required for prophylaxis. It is important that these patients are
authors suggested that the problem was secondary to calcifica- identified early in pregnancy and a plan is devised by the hema-
tion and aggregation of elastic fibers in the laryngeal ligaments tologist, obstetrician, and anesthesiologist. Regional anesthesia is
and cartilage. contraindicated.


Factor deficiencies Factor II (FII, prothrombin) deficiency
There are several excellent reviews on this subject.16,228,229,230,231 Factor II (prothrombin) is a glycoprotein synthesized in the liver.
Along with factors VII, IX, and X, it is vitamin K-dependent. Factor
II is necessary for conversion of fibrinogen to fibrin, aggregation
Fibrinogen (factor I, FI) deficiency
of platelets, activation of plasminogen, activation of thrombin-
Fibrinogen is a protein synthesized in the liver with a half-life activatable fibrinolysis inhibitor, activation of factors V, VIII, XI,
of approximately four days. Fibrinogen is necessary for normal and XIII, and activation of protein C in the presence of thrombo-
platelet aggregation and a functional fibrinogen level <0.5 g/l is modulin. Factor Xa activates FII on the surface of platelets in the
associated with microvascular bleeding. There are three conge- presence of FV and calcium.
nital abnormalities of fibrinogen deficiency: afibrinogenemia, Factor II deficiency is the rarest inherited bleeding disorder
hypofibrinogenemia, and dysfibrinogenemia.16 In afibrinogen- with a prevalence of 1:2 000 000.16 It is inherited in an auto-
emia there is a total absence of fibrinogen; hypofibrinogenemia somal recessive manner and is often seen in situations of con-
refers to a decreased level of normally functioning fibrinogen; sanguinity. There are two types of FII deficiency: type I
while in dysfibrinogenemia the fibrinogen is functionally (hypoprothrombinemia “ where antigen and activity levels are
abnormal. low) and type II (dysprothrombinemia “ where antigen levels
Afibrinogenemia is inherited in an autosomal recessive manner are normal but activity is low). Patients with type I deficiency
and is due to defective synthesis. Afibrinogenemia has a preva- often have mucosal and soft tissue bleeding as well as hemar-
lence 1:1 000 000 and is often associated with consanguinity. throsis. The PT and aPTT may be prolonged (see Table 17.2) but
Bleeding due to afibrinogenemia may be life threatening but are occasionally normal; thus, if this disorder is suspected clini-
cally, further testing is required.235
there are long periods where there is no bleeding. Bleeding asso-
ciated with hypofibrinogenemia is generally milder and may Obstetric complications in women with hypoprothrombinemia
include spontaneous fetal loss and PPH.236 Bleeding in type II
follow invasive procedures, such as surgery. Women with afibri-
nogenemia and hypofibrinogenemia may have recurrent preg- deficiency is usually more variable, and these women may be
nancy loss as well as antepartum and postpartum hemorrhage asymptomatic or have mild bleeding symptoms.
and thromboembolism.
Some women with dysfibrinogenemia are asymptomatic while
Factor V (FV) deficiency
others will have episodes of hemorrhage or thrombosis. Bleeding
may not correlate with the fibrinogen level or thrombin time. Factor V is a large glycoprotein that is synthesized in the liver and
in megakaryocytes.16 Platelets normally contain approximately
Fibrinogen deficiency can also be acquired. Treatment of afibri-
nogenemia is fibrinogen concentrate. Some authors recommend 20% of the circulating FV. Factor V is activated by thrombin and
using fibrinogen concentrate prophylactically throughout preg- acts as a cofactor for FXa in converting prothrombin to thrombin
nancy beginning once pregnancy is confirmed.16 Fibrinogen con- (FII to FIIa). Factor Va is downregulated by activated protein C to
centrate may be ineffective in women with dysfibrinogenemia, maintain normal hemostatis.
while other measures such as topical fibrin glue or tranexamic Factor V deficiency is a rare autosomal recessive disorder with a
acid may be useful. Avoid invasive monitoring and procedures on prevalence of 1:1 000 000 that is often seen in consanguinous
the fetus in women with dysfibrinogenemia as it is assumed that situations. In the homozygous state, there may be moderate to



310
Chapter 17


severe bleeding. Postpartum hemorrhage has been reported used. Thrombosis has also been reported in association with
FVII deficiency with speculation as to the reason.16,241
in pregnant women with this disorder. Laboratory testing will
show a prolonged PT and aPTT with a normal thrombin time In normal women, FVII levels increase during pregnancy, but it
(see Table 17.2). The abnormal PT and aPTT can be corrected is unclear whether this happens in women with FVII deficiency.
by mixing the patient™s serum with normal serum. Treatment of Several reports of management of FVII deficient pregnant
bleeding episodes is with fresh frozen plasma (FFP). women have been published, and recent reports highlight the
prophylactic use of rVIIa to prevent hemorrhage.242,243,244 There
There are few reports of FV deficiency in pregnancy. A retro-
spective report described the experience of pregnancy and the is a report of rVIIa administration prior to induction of epidural
anesthesia for C/S.245 The rVIIa infusion was continued for four
use of oral contraceptives in women with FV deficiency (homo-
zygous and heterozygous).237 There were five homozygous days postpartum without complications. The literature is other-
patients and two of these had a total of three pregnancies. wise silent on the anesthetic management of patients with FVII
One of these was known to have FV deficiency and received deficiency. Obviously, if there is evidence of a coagulopathy
prophylactic FFP two hours before C/S; this was followed by (prolonged PT or INR), neuraxial anesthesia is contraindicated
repeat transfusion of FFP for five days postpartum. No mention and options for labor include intravenous opioids and for cesar-
is made of anesthesia and no details are given regarding her other ean delivery, general anesthesia.
pregnancy, which presumably was managed in a similar fashion.
In the other woman, FV deficiency was detected following
Von Willebrand disease
excess bleeding at delivery. In heterozygotes, 15 pregnancies in
11 women were uneventful.237 In another report a women had Von Willebrand disease is the most common inherited bleeding
disorder with a prevalence in the general population of 1%.246
undetectable FV levels and although she had minimal bleeding
problems (bruising and occasional epistaxis) she was advised not It has an autosomal dominant pattern of inheritance and is seen
to have an epidural.238 She had an emergency C/S under general equally in males and females. Unlike hemophilia, phenotypic
anesthesia and received two units of solvent-detergent plasma. expression of VW disease varies within families. Approximately
There was minimal blood loss during surgery or postpartum. 90% of patients classify as type 1, which is characterized by a
Bolton-Maggs et al. recommend FFP once the woman is in estab- decrease in the level of plasma FVIII:VWF antigen and activ-
lished labor followed by monitoring of FV levels.16 However, one ity.247 The other subtypes of VW disease (IIa, IIb, IIM, IIN, III,
may wish to use solvent-detergent plasma rather than FFP due platelet) involve abnormal configurations of the multimer and
to the lower risk of transmitting infection. As with any blood varying abnormalities of plasma- and platelet-associated
VWF.247 The majority of those patients who are not type I are
products, inhibitors to the factors may develop so the number
of blood products should be limited. type II variants. Type III VW disease has a prevalence of

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