LINEBURG


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Waldenstrom macroglobulinemia
chronic leukemia during pregnancy (90%) is chronic myeloid
leukemia (CML). Therapy during pregnancy is usually supportive; This disorder is characterized by an IgM monoclonal gammopa-
however, there are reports of treatment with interferon-a during thy and recurring purpura. Patients with this disorder have hepa-
pregnancy.111 tosplenomegaly, frequently a mild anemia, and usually some
degree of renal insufficiency. It is very rare in pregnancy with
only one reported case.123 That pregnancy was complicated
Myelofibrosis
Myelofibrosis is an extremely rare disorder in pregnancy possibly by IUGR and fetal distress leading to C/S under general anesthe-
because the outlook of this disorder is bleak. In the past myelo- sia. These patients usually have normal screening coagulation
fibrosis was thought to be the outcome of polycythemia vera studies, a normal platelet count, and, in the absence of any



301
5 Other disorders


obvious purpura, a low bleeding risk. However, they may be at the woman had uneventful regional anesthesia. The authors
increased risk for thrombosis as a result of hyperviscosity related commented that the coagulation profile should be normal and
to the level of monoclonal IgM protein. acquired VW disease ruled out prior to administering neuraxial
anesthesia.
Anesthetic management of patients with acute leukemia
Anesthetic management for patients with
shares similar principles to that of aplastic anemia, since the
malignant marrow disorders
complications of anesthesia and surgery relate to the pancyto-
Theoretically both regional and general anesthesia can be used in penia associated with these disorders and/or their treatment.
women with ET unless there is evidence of platelet dysfunction or In patients with acute leukemia, aggressive large cell lymphoma,
ongoing hemorrhage, in which case regional anesthesia is contra- or chronic granulocytic leukemia (CGL) who remain untreated
indicated. In a patient presenting in the third trimester with a at the time of delivery, special attention must be given to the
platelet count >1500 ‚ 109/l, consider urgent plateletpheresis to level of blast cell count or, in the case of CGL, the total WBC
reduce the platelet count, minimizing the risk of thrombosis and count. Significantly increased blast cell counts place the patient
bleeding. Postpartum, rebound severe thrombocytosis often at risk for hyperviscosity syndrome leading to renal compromise,
occurs: this should be anticipated and intervention with chemo- cerebral infarction, and other complications. Leukopheresis or
therapy and/or plateletpheresis, as well as low-dose aspirin, may rapid reduction of WBC count with chemotherapy may reduce
minimize the risk of thrombosis. the risks of anesthesia and labor. Vigorous hydration is essential
There are multiple reports of women with ET undergoing with close monitoring of urine output and renal function.
C/S but there is only a single report of the anesthetic mana- Although some of these women have delivered by C/S there is
gement.124 In this case, coagulation was assessed at 38 little information regarding anesthesia. Spencer and colleag-
weeks™ gestation using TEG followed by uneventful epidural ues described a parturient with multiple medical issues (myo-
analgesia ten days later for labor analgesia. The authors cardial infarction, congestive heart failure, diabetes mellitus,
noted that while TEG may be helpful, success in a single asthma, two previous C/S, mild preeclampsia) in addition to
CML, with suboptimal control.131 The woman refused epidural
patient does not prove the safety of relying on TEG. Of note,
at the time of the TEG, the woman had ecchymoses of her anesthesia and general anesthesia was uneventful. There was no
lower extremity and a platelet count >1000 ‚ 109/l. Based on discussion regarding the implications of her poorly controlled
these findings many anesthesiologists would consider neuraxial leukemia.
block contraindicated. Bucklin and coworkers reported a clinical dilemma whereby
There are a few reports of anesthesia in the nonobstetric ET a parturient with acute myelogenous leukemia developed a
postdural puncture headache (PDPH).132 Although epidural
population, and they underline the importance of ensuring that
preoperative platelet counts and platelet aggregation tests are blood patch was considered, symptomatic treatment was given
within the normal range before considering neuraxial anesthe- due to concerns about the risk of infection and central nervous
sia.125 As thrombosis is a major risk in patients with ET, consider system leukemia. The PDPH resolved ten days after the dural
thromboprophylaxis.126 Invasive monitoring may be hazardous puncture.
as there are reports in which radial artery thrombosis with Anesthetic concerns in women with lymphoma relate to the
degree of cardiorespiratory compromise,116,117 and multidiscipli-
subsequent necrosis followed radial artery catheterization in ET
patients.127,128 One case received spinal anesthesia,127 and the nary involvement is essential. One patient with a mediastinal
other general anesthesia.128 tumor, had a C/S five days following initiation of chemotherapy,
In general, PV patients have a high risk of hemorrhagic and thereby preceding the nadir of pancytopenia. As her condition was
thrombotic complications related to surgery.129 This is controlled stable, uneventful epidural anesthesia was provided. Appropriate
by maintaining the hematocrit in the range of 0.40“0.45 with equipment was present in the operating room to manage any
airway problems that might have arisen.116 In another report,117
phlebotomy. In the event of emergency C/S, attention should be
paid to positioning (to prevent venous stasis) and hemodilution a parturient with a 32-week twin gestation had recurrent upper
should be performed, preferably with associated phlebotomy if gastrointestinal bleeding. She required emergency C/S under gen-
the hematocrit is >0.45. Maintain normotension and provide eral anesthesia. Following delivery, during upper gastrointestinal
supplemental oxygen. endoscopy, difficulty with ventilation was noted and an emergent
Although the advantages of vasodilatation, improved regional computed tomography (CT) scan demonstrated a non-Hodgkin
blood flow, and hemodilution that occur with regional block- lymphoma mediastinal mass.
ade and intravenous fluid preload are significant, regional
anesthesia is avoided if the hematocrit is poorly controlled
Bone marrow transplantation
because of an unpredictable bleeding risk. Careful monitoring
of fluids will prevent circulatory system overload, which could
Pregnancy has been reported following bone marrow transplan-
induce cardiac failure. There is one report of epidural anesthe-
tation for aplastic anemia and hematologic malignancies,133 but
sia for C/S in a parturient with PV and preeclampsia.130 During
is relatively uncommon when total body irradiation (TBI) is given
her pregnancy she was treated with IFNa and prednisone.
prior to transplant. Anesthetic management should focus on the
Her coagulation profile was normal the day of surgery and



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Chapter 17


Platelet disorders
patient™s current status as multiple sequelae may result from the
procedure. The technique of choice for analgesia and anesthesia
Thrombocytopenia
will be based on the current hematologic and clinical condition.134
Total body irradiation and/or chemotherapy can produce pulmon- Thrombocytopenia is the most common hematologic complica-
ary fibrosis so pulmonary function should be assessed. Strict aseptic tion in pregnancy. The etiology varies from an apparent physio-
technique is required as these patients are prone to infection. logic condition (gestational thrombocytopenia) to disorders
Generally speaking there is no contraindication to the use of general associated with significant underlying pathology. The implica-
or regional anesthesia. These patients are at risk for both transfusion- tions of a low platelet count with regard to anesthetic considera-
associated infection and alloimmunization to RBCs and platelets.135 tions in the pregnant woman vary according to the underlying
pathophysiology of the thrombocytopenia (see Table 17.4).
Most authorities agree that the platelet count progressively
Coagulation disorders
decreases throughout gestation until 32“36 weeks, associated with
a consistent increase in mean platelet volume.11,12,139 This suggests
In the past regional anesthesia was considered contraindicated
an increase in platelet consumption (younger platelets being larger)
in any patient with a bleeding abnormality, even if there was no
but limited kinetic studies have failed to confirm a shortened plate-
evidence of overt bleeding or bruising. This applied to parturients
let life span in pregnancy. A study of platelet behavior demon-
with platelet counts <100 ‚ 109/l, mild VW disease and those
strated an increase in platelet reactivity in the third trimester.140 It
treated with heparin and/or aspirin. With better understanding
should be remembered that platelet activation is the first stage of
of the pathophysiology of these disorders and the changes that
in vivo hemostasis. In patients with hypoplastic thrombocytopenia
occur with pregnancy, anesthesiologists are becoming more
and platelet counts <100 ‚ 109/l, there is a relationship between
liberal in their use of regional anesthesia. Within certain limita-
platelet counts and the bleeding time.141 In conditions such as
tions, it is unlikely that this change will be accompanied by an
ITP, this relationship is shifted to the left, and in patients with
increase in anesthetic-related complications.
platelet dysfunction, to the right. The use of aspirin or nonster-
The major concern with regional anesthesia relates to the
oidal anti-inflammatory drugs (NSAIDs) in patients with any of
development of a spinal or epidural hematoma with resulting
these disorders can dramatically shift the relationship between
permanent neurologic damage. The incidence of this complica-
platelet count and platelet function. Therefore, these drugs
tion in parturients is extremely low,136,137,138 and it is difficult to
should not be used in patients with thrombocytopenia.
determine the relationship between epidural hematoma, regional
anesthesia, and coagulopathy.
For many coagulation disorders, there is no concensus as to the Table 17.4 Disorders of platelets during pregnancy
most appropriate anesthetic management. The obstetric litera-
Abnormal platelet
ture indicates that patients with many of these unusual condi-
Disorder Thrombocytopenia function
tions have received anesthetic care. Some general principles for
anesthetic management of the parturient with a coagulation dis- Gestational Yes No
order are outlined in Table 17.3. thrombocytopenia
ITP Yes No
May Hegglin anomaly Yes Possibly
Table 17.3 Principles of anesthetic management of patients
Antiphospholipid Yes Very unusual
with a bleeding disorder
syndrome
HIV Yes No
1. Take a thorough history: emphasis on family history of bleeding,
Microangiopathic Yes Only, if significant
bruising (especially during surgery, dental work)
syndromes decrease in
2. Do a thorough physical examination: bruising, bleeding, petechiae
fibrinogen
(blood pressure cuff, i.v. sites)
Bernard Soulier Yes Yes
3. Lab work: CBC, platelet count, specific testing dependent on
syndrome
history, clinical course
Chediak Higashi No Yes
4. Involve hematologist, if appropriate
syndrome
5. Assess airway, feasibility of other techniques
Platelet storage pool No Yes
6. Discuss risks/benefits of proposed procedure and what is known
deficiency
about risk
Glazmann No Yes
7. Discuss risks/benefits of blood products
thrombasthenia
8. Document discussion of 6 and 7
Von Willebrand No, except with Yes
9. Proceed with regional anesthesia, if appropriate
disease variant type IIB
10. Remember, if regional contraindicated so are pudendal block,
intramuscular injections, NSAIDs, aspirin
ITP ¼ idiopathic/immune thrombocytopenic purpura; HIV ¼ human
immunodeficiency virus
CBC ¼ complete blood count




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5 Other disorders


Gestational thrombocytopenia (incidental assessment using percutaneous umbilical cord or fetal scalp-
thrombocytopenia of pregnancy) vein sampling of fetal platelets prior to delivery was appropriate
in the small number of patients considered at high risk to deliver a
Gestational thrombocytopenia occurs in approximately 8% of all
severely affected infant.151,152,153 Due to the high incidence of
pregnant women.142 It is generally mild with a platelet count
fetal mortality, these procedures are no longer recommended.139
greater than 90 ‚ 109/l, although it may be lower. Patients and
Neonates of ITP mothers should be followed daily until their
their neonates are not at increased risk of bleeding, and the
platelet count has stabilized (usually within three days). Recent
platelet count in the majority of patients returns to normal three
practice guidelines do not recommend routine C/S for women
to five days postpartum. This pattern may be repeated in sub-
with ITP.139
sequent pregnancies.143
In preparation for delivery, it is often appropriate to administer
The diagnosis of gestational thrombocytopenia is usually one
a short course of steroids or IVIG at 37“38 weeks™ gestation to
of exclusion. Diagnosis is based on a normal platelet count in
elevate the platelet count, ensuring a full range of options for
early pregnancy, no previously documented thrombocytopenia
analgesia in these patients. There is no role for platelet transfu-
prior to pregnancy, and the absence of clinical evidence for
sion unless there is life-threatening bleeding. Aspirin and NSAIDs
impending preeclampsia. Thrombocytopenia that occurs prior
are contraindicated.
to pregnancy, or within the first trimester of pregnancy, is gener-
Anesthetic management of women with ITP is usually straight-
ally ITP. Parturients with uncomplicated gestational thrombo-
cytopenia can have regional anesthesia safely.144,145 forward. In most instances platelet function is excellent and a
platelet count of >75 ‚ 109/l is more than adequate for regional
Idiopathic/immune thrombocytopenic purpura anesthesia. A history of a lack of bleeding problems at a given
platelet count should reassure the anesthesiologist, and a careful
This is a common disease in young women and has an incidence
of approximately 0.01“0.02% of deliveries.146 Studies on its patho- physical examination will assess hemostasis prior to neuraxial
block. Many anesthesiologists are comfortable administering
physiology have revealed the presence of platelet-specific auto-
neuraxial anesthesia, especially spinal anesthesia, to parturients
antibodies (usually IgG), which recognize immunogenic
with ITP and platelet counts between 50 and 75 ‚ 109/l. In the
glycoproteins on the platelet membrane. Generally speaking,
past it was recommended that women not receive neuraxial block
thrombocytopenia is related to increased destruction of sen-
unless the platelet count was >75“100 ‚ 109/l but there is little
sitized platelets in the RE system; however, there is also evi-
evidence to support this practice.21,139 In our center, women with
dence for antibody-mediated impaired thrombopoiesis.147,148
ITP and platelet counts >50 ‚ 109/l are routinely offered regional
Laboratory findings usually include isolated thrombocytopenia
anesthesia providing there are no other specific contraindications
(antedating pregnancy or presenting early in pregnancy) with
to its use. In special situations, such as fetal distress and a difficult
large well-granulated platelets and often normal hemostasis in
maternal airway, platelet counts as low as 40 ‚ 109/l may well be
spite of a significantly reduced platelet count. Not infrequently,
safe for spinal anesthesia (risk of neuraxial bleeding is less than
there is a family history of autoimmune disease. The most
risk of emergency general anesthesia).
common conditions in the differential diagnosis include thrombo-
cytopenia associated with SLE, human immunodeficiency virus
Wiskott-Aldrich syndrome (WAS)
(HIV) infection, and antiphospholipid antibodies. There is no
Wiskott-Aldrich syndrome is an X-linked recessive disease with a
specific laboratory test, and routine measurement of platelet
antibodies is not recommended.139 Rarely, there is a concomitant poorly understood pathophysiology. As it is X-linked, it is found
mainly in males and is associated with developmental defects of
platelet functional abnormality.
platelets, lymphocytes, and possibly other bone marrow-derived
There are insufficient data to recommend treatment of the
cell lineages resulting in immunodeficiency, thrombocytopenia,
asymptomatic parturient who has a platelet count above
20“30 ‚ 109/l during the antenatal period.139 At our institution, eczema, and susceptibility to malignancies. Platelets are typi-
cally small and thrombocytopenia may cause severe bleeding,
treatment (prednisone or IVIG) is administered when there is
requiring platelet transfusions. Hematopoietic stem cell trans-
impaired hemostasis during pregnancy or to elevate the platelet
plantation corrects the thrombocytopenia and the immunodefi-
count prior to delivery or an invasive procedure. Those patients
ciency.154 Normally female carriers have no clinical signs, but
who require therapy usually respond to prednisone 1 mg/kg or
occasionally females have microthrombocytes without other
IVIG 2 g/kg over two to five days. Those who fail to respond to
findings of the syndrome. There are two reports of females with
either therapy may respond to a combination of the two. Rarely
Wiskott-Aldrich syndrome-related thrombocytopenia with a
splenectomy is required during pregnancy and is best done dur-
wide spectrum of platelet size, including giant platelets.155,156
ing the second trimester.
In one family, this disorder was transmitted in an autosomal
Infants born to mothers with ITP may be thrombocytopenic
dominant fashion.155 To date, no pregnant women with this
because the antibody crosses the placenta.149,150 Approximately
disorder have been reported.
5% of neonates born to mothers with ITP have significant thrombo-
cytopenia (<50 ‚ 109/l) at birth; however, over the few days
Other causes of thrombocytopenia
following birth, approximately 30“40% of neonates with a normal
There are several other causes of thrombocytopenia that are not
or near-normal count at delivery may become significantly
pregnancy specific. Spurious thrombocytopenia results when
thrombocytopenic. In the past, it was suggested that an



304
Chapter 17


functional binding site on the platelet membrane for VW factor.
Thus, GPIb-deficient platelets cannot bind to the subendothe-
lium of the injured vessel in vivo. A prolonged bleeding time is
characteristic of the disorder. Platelet aggregation studies reveal
normal aggregation to ADP, collagen, and epinephrine but no
response to ristocetin. Complications that occur during preg-
nancy include intrapartum bleeding and PPH (two to three
weeks).160,161 Platelet transfusions are ineffective if previous
transfusion has resulted in alloimmunization to platelet glyco-
protein Ib:IX. Furthermore, in the presence of this type of platelet
specific antibody, the fetus may be at risk for immune-mediated
thrombocytopenia, indistinguishable from neonatal alloimmune
thrombocytopenia. There is one report of a successful pregnancy
following treatment with IVIG.160 In another report, a woman had
post cesarean bleeding that required tranexamic acid; this report
did not mention anesthesia.162 These authors reviewed the litera-
ture for management during pregnancy and found 16 pregnan-
Figure 17.3 A peripheral blood smear demonstrating platelet clumping cies in 9 women with this diagnosis. Postpartum hemorrhage
showing the comparative size of the clump with a white blood cell. (See color (immediate, early, or delayed) occurred in all but three of the
plate section.) pregnancies. One case that did not report a PPH was an elective
cesarean hysterectomy, as suitable platelet transfusion products
were not available.162
platelets are clumped and the automated counter ˜˜sees™™ them
Close involvement with a hematologist is important, partic-
as WBCs. Review of the peripheral blood smear will result in a
ularly in the setting of an alloimmunized patient. Principles of
correct platelet count (see Figure 17.3). Thrombocytopenia may
result from viral infections (HIV,157 cytomegalovirus, Epstein Barr anesthetic management include avoidance of invasive proce-
dures such as intramuscular injections and regional anesthesia,
virus) and drug therapy (heparin, sulphonamides, penicillin,
rifampicin, quinine).158 Another cause of immune thrombocyto- including pudendal block. Platelet transfusion may be necessary
if the patient is not alloimunized. Intravenous narcotic analgesia,
penia is that associated with antiphospholipid antibodies (lupus
nitrous oxide/oxygen in a 50:50 mixture for labor analgesia and
anticoagulant, anticardiolipin antibodies, antibodies that cause a
general anesthesia for C/S are reasonable options. Aspirin and
false positive serologic test for syphilis). Approximately 25% of
NSAIDs are contraindicated.
patients with these antibodies have concomitant thrombo-
cytopenia; however, the overriding risk is for thrombotic com-
MYH9-related disease
plications, rather than hemorrhage. These patients are at risk for
Mutations in the MYH9 gene (responsible for nonmuscle myo-
a variety of adverse pregnancy outcomes, related mainly to pla-
sin heavy chain IIA) on chromosome 22 result in autosomal
cental compromise such as IUGR, abruption, severe and often
dominant macrothrombocytopenias.164 These disorders include
early onset preeclampsia (<26 weeks™ gestation), intrauterine
May-Hegglin anomaly, Sebastian syndrome, Fechtner syn-
death, placental infarction, recurrent miscarriage. The combina-
drome, and Epstein syndrome. Fechtner syndrome is similar
tion of low-dose heparin and low-dose aspirin (81 mg daily) is
to Alport syndrome in that nephritis, sensorineural hearing
very successful and is currently the treatment of choice. In those
loss, and congenital cataracts are present. However, there is
who have suffered recurrent thrombosis prior to pregnancy
also macrothrombocytopenia and polymorphonuclear inclu-
necessitating long-term anticoagulation, therapeutic anticoagu-
sions called D¨ hle-like bodies that are not present in Alport
o
lation with heparin combined with aspirin is necessary through-
syndrome. Epstein syndrome does not have cataracts or
out pregnancy. Providing these patients are not on therapeutic
D¨ hle-like bodies. Characteristics of May-Hegglin anomaly
o
heparin, regional anesthesia is not contraindicated, but attention
has to be paid to the timing of the block.159 and Sebastian syndrome include thrombocytopenia, large plate-
lets, and leukocyte inclusions, the latter differing in the two
syndromes.164,165 There are several reports of pregnancy in
Platelet functional disorders
these various syndromes.166,167
Bernard-Soulier syndrome May-Hegglin anomaly is a rare hereditary disorder character-
ized by giant platelets and blue inclusions in the cytoplasm of
This is a rare, autosomal recessive bleeding disorder character-
leukocytes. It is inherited as an autosomal dominant trait with
ized by low normal or diminished platelet count, giant platelets,
variable penetrance. These patients have thrombocytopenia and
and platelet dysfunction. Clinically, patients with this disorder
platelet dysfunction. Platelet levels range from 10 ‚ 109/l to nor-
have moderate to severe bleeding of the purpuric type. Very few
mal levels and there may be a bleeding diathesis. Generally, these
pregnancies have been reported in women with this disor-
der.160,161,162,163 Platelets from these patients have a deficiency patients are asymptomatic but occasionally they have severe
bleeding episodes related to thrombocytopenia.
of platelet glycoproteins Ib, IX and V. GPIb:IX is an important



305
5 Other disorders


There are several reports of pregnancy in patients with the removal by plasmapheresis may be performed prior to platelet
May-Hegglin anomaly.168,169,170,171,172,173 Most have delivered transfusion.
by C/S since the fetus, if affected, is at risk of intracranial hemor- While bleeding can often be controlled using conservative
rhage. One case report documented a vaginal delivery after per- measures (e.g. pressure), other agents such as topical thrombin,
cutaneous umbilical blood sampling demonstrated a fetus with epsilon aminocaproic acid, and tranexamic acid may be required
the May-Hegglin anomaly but an adequate platelet count.173 during surgery. There are reports of the use of recombinant factor
VIIa in GT parturients.178,179

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