LINEBURG


<< . .

 51
( 87)



. . >>

nosis is by low plasma and high urinary copper levels and very low
Budd-Chiari syndrome
plasma ceruloplasmin, or by liver biopsy with copper assay.2,3,54
This syndrome, characterized by thrombotic occlusion of hepatic
Treatment and obstetric implications veins, is rare in pregnancy. In 105 cases, only one presented during
pregnancy, but fifteen presented four days to three weeks post-
Treatment consists of eliminating foods containing copper, and
partum.64 The etiology is uncertain, but the hypercoagulable state
removing and detoxifying copper deposits. If untreated the dis-
of pregnancy may be a predisposing factor. Liver biopsy shows
ease is fatal within a few years. Chelating agents increase renal
congestion and centrilobular liver necrosis,1,2,3,4,54 and the clinical
copper excretion. Due to its many serious side effects penicilla-
features include hepatomegaly, sometimes ascites, and occasion-
mine is no longer used and has been replaced by alternatives such
ally acute liver failure. The onset may be insidious over months or
as chelators like zinc (induces hepatic metallothionine to seques-
acute, and diagnosis is made with Doppler flow studies, venogra-
ter hepatic copper), trientine, or, in the symptomatic phase, tet-
rathiomolybdate (blocks intestinal absorption of copper).59 Zinc phy, or magnetic resonance imaging. Anticardiolipin antibodies
may be detected and there are several associated diseases (see
is the treatment of choice for asymptomatic and pregnant
patients because of its efficacy and lack of toxicity,59,60,61 whereas Table 14.8). Management is with heparin and oral anticoagulants,
but the obstruction may be resistant to anticoagulation, thrombo-
those with hepatic or neurological involvement receive tetrathio-
lytic therapy, and other attempts at revascularization.1,2,3,4,54,65
molybdate.59 Liver transplantation has been performed success-
Maternal prognosis is poor. Surgical intervention for shunting
fully for fulminant hepatitis.
is associated with high mortality,64,65 and liver transplantation
Pregnancy is unlikely in untreated disease, because amenorrhea,
may be required.1 Antenatal presentation is associated with a
subfertility, and spontaneous abortion are common. However,
poor prognosis. In addition to the detailed assessment of liver
early copper chelation allows normal fertility and in the absence
function and the application of appropriate anesthetic principles,
of severe liver disease, portal hypertension, or esophageal varices,
the implications of anticoagulation must be considered.
pregnancy outcome is good. Estrogen induces a rise in plasma



256
Chapter 14


Peliosis hepatitis Nevertheless, surgery may be required urgently because of cyst
torsion or rupture, or to remove large cysts that obstruct labor.70
This rare infectious disease is caused by the gram-negative bac-
teria genus Bartonella, best known because one species causes
˜˜cat scratch disease™™. These bacteria are widespread and cause
Liver emergencies
opportunistic infection with diverse clinical manifestations,
Hepatic rupture
including angiomatosis, liver and spleen vasculitis, and endocar-
There are over a hundred case reports of liver rupture in preg-
ditis. Liver pathology is characterized by irregular blood-filled
nancy, with trauma75 or rupture of a subcapsular hematoma
spaces and cystic dilation of hepatic sinusoids, sometimes with
associated with severe preeclampsia being common causes.
calcification. Patients may be asymptomatic, or experience com-
Other pathology includes rupture of intrahepatic hemangiomas,
plications such as portal hypertension, liver failure, or intraperi-
tumor, and abscess (pyogenic, amoebic, or parasitic), or in asso-
toneal hemorrhage. Cases in pregnancy and the puerperium have
been reported, including immunodeficient patients.66,67 Disease ciation with cocaine abuse. Most cases that complicate pre-
regression may occur with antibiotic treatment,68 and successful eclampsia occur in late pregnancy or peripartum, and arise from
hepatic artery embolization has been described.67 an intraparenchymal hematoma in the superior and anterior
sections of the right lobe, rupturing along the inferior edge of
the right lobe.3,4
Autoimmune hepatitis
This diagnosis should be suspected in any pregnant woman
This chronic disease of uncertain origin may affect women of
who presents with RUQ pain, signs of peritoneal irritation, or
childbearing age, but pregnancy is uncommon because of asso-
hypovolemia. Diagnosis can be confirmed with a contrast CT
ciated hypothalamic-pituitary dysfunction. With immunosup-
scan, but if the patient is unstable the diagnosis may be made
pressive therapy menstruation returns and pregnancy becomes
with abdominal ultrasound, diagnostic peritoneal lavage, or
possible. The immunotolerance of pregnancy has a positive effect
exploratory laparotomy. Both fetal and maternal mortality
on disease progression, but postpartum relapse is very frequent.69
approach 60%.76,77 In stable patients, a nonoperative approach
Treatment with prednisolone is considered safe, although first
involving observation and transfusion is preferred.78 However,
trimester use is associated with a small risk of cleft palate.
early surgery has helped reduce mortality and surgical options
Azathioprine is safe throughout pregnancy.3,27
involve packing, oversewing, hepatic artery embolization or liga-
tion, and partial lobectomy.
Hydatid disease
Acute liver failure
Hydatid disease or cystic ecchinococcosis is a parasitic disease
Acute liver failure during pregnancy results from loss of hepato-
found worldwide but most prevalent in countries in the
cellular function as a result of a constellation of disorders such as
Mediterranean, South America, Middle East, and the Pacific,
fulminant viral hepatitis, poisoning by hepatotoxins, Wilson dis-
where the incidence is from 1“220 per 100 000. In the USA a few
ease, and AFLP. Cardiovascular changes include low systemic
hundred cases are reported each year. Primarily a disease of
vascular resistance and increased cardiac output. Hypoxemia
sheep and cattle, humans are accidental hosts, with the adult
results from pulmonary edema, pneumonia, pleural effusion,
worm containing eggs transmitted in canine feces. Larvae
adult respiratory distress syndrome (ARDS), or hypoventilation
develop in the intestine and penetrate the wall to the portal
associated with cerebral edema. The hepatorenal syndrome leads
circulation and go to the liver. However, cysts also may occur in
to oliguria, renal failure, and transient diabetes insipidus.
the spleen, mesentery, and pelvis, although not in the placenta, so
the neonate is not exposed.70 Cysts are often asymptomatic. Hypoglycemia is a consequence of defective gluconeogenesis
and inadequate insulin uptake. Disseminated intravascular coa-
Diagnosis is by ultrasound and confirmed by an indirect hemag-
gulation is present in the majority of cases.79 Fluid and electrolyte
glutination test.
status must be assessed regularly, and dehydration or excessive
The disease is rare during pregnancy, with a rate of less than 1 in
diuresis may need correction. Exchange transfusion, plasma-
30 000 even in endemic areas, and there are only a few published
pheresis, extracorporeal perfusion, and steroids all have a place
case reports. It has been postulated that cysts may expand and
in the treatment of acute liver failure. Despite treatment the
present during pregnancy because of decreased cellular immu-
nity.71 Medical treatment is with antihelmintics such as albenda- maternal and fetal mortality is high (40% and 60% respectively,
in one series).79
zole and mebendazole. Drug therapy is usually reserved for
recurrent disease or where surgery is impossible, but use during
pregnancy is controversial.72 Teratogenicity and embryotoxicity are Anesthetic implications
The anesthesiologist may be required to manage an urgent deliv-
reported in some animal models, although a safe dose has been
ery or liver transplantation, in a woman who is coagulopathic and
determined in sheep. Antihelmintics have been used in human
pregnancy without ill effect.72 Perioperative albendazole has been encephalopathic (with restlessness, confusion, asterixis, seizures,
successfully combined with surgery72,73,74 to cure the disease, psychosis, or coma). The choice of anesthetic technique is deter-
mined by the degree of coagulopathy and mental obtundation,
although the World Health Organization does not recommend
with regional anesthesia preferable for C/S but rarely feasible.
surgery during pregnancy because of the risk of intra-abdominal
General anesthesia may reduce hepatic blood flow because of
dissemination or severe anaphylaxis from spill of cyst contents.



257
4 Metabolic disorders


controlled ventilation and the effect of inhalational anesthetic is rare. The disease shows a wide clinical spectrum and variable
drugs. Propofol does not reduce hepatic blood flow or show natural history, and patients are usually asymptomatic, although
altered pharmacokinetics in cirrhosis,42 so propofol and desflur- symptoms may include pruritus, jaundice, and fatigue. Serum
ane or isoflurane, or total intravenous anesthesia with propofol, ALP and GGT are raised, and aminotransferases and bilirubin
are options.80 Caution with drug dosing is advised as prolonged may be mildly elevated.88,89 It is not known whether pregnancy
responses can occur. For rapid sequence induction succinylcho- causes deterioration, although some reports describe worsening
liver function in women with PBC during pregnancy.88 Maternal
line may have a less predictable duration, as may rocuronium,
which undergoes hepatic metabolism. Atracurium is the neuro- and fetal outcomes are variable, with premature delivery and
muscular blocker of choice because it undergoes Hoffman elim- stillbirth described, but good outcome can be expected in well-
compensated disease.90 Management is with UDCA antenatally
ination. Nevertheless, use of a peripheral nerve stimulator is
and after the first trimester,91 but methotrexate is teratogenic and
recommended as metabolic acidosis may alter the duration of
neuromuscular blockers. If multiorgan failure is present or the must be avoided. Ursodeoxycholic acid has unknown embryo-
patient is unstable at the end of surgery, postoperative ventilation toxicity but appears safe. Liver transplantation is the only defini-
and intensive monitoring are essential. tive therapy for advanced disease.
Primary sclerosing cholangitis is another rare disease that is
associated with inflammatory bowel disease. The only effective
Diseases of the biliary tract
means of halting disease progression is liver transplantation.
Cholelithiasis, cholecystitis, choledocholithiasis, During pregnancy, pruritus may be prominent, but the course
and pancreatitis of the disease appears unaltered and neonatal outcome is usually
good.92
During late pregnancy and the early postpartum period there is a
predisposition to cholelithiasis, a result of increased serum lipid
concentrations, slowing of bile acid excretion, and reduced small
Renal disease
intestinal motility. Gall bladder motility returns to a prepregnant
level a few days after delivery.2,3 Despite these changes, acute Until recently, successful pregnancy among patients with severe
cholecystitis is uncommon, with a prevalence of 1 in 1000“10 000 renal disease was unusual, but with better medical care, this
pregnancies.81,82 The clinical presentation is typical, with RUQ has now become commonplace. Published experience specific
pain and tenderness, fever, and leukocytosis, and the course of to the management of pregnant women with renal disease is
the disease is unchanged. Back pain (supported by raised serum limited, possibly because some renal diseases have little impact
amylase) indicates pancreatitis, which can be associated with alco- on obstetric and anesthetic management, while in others preg-
hol or viral illness.83 Pancreatitis results in long periods without nancy is unusual. Systemic diseases that cause renal pathology,
oral intake, longer hospital stay, and lower neonatal birth weight. include diabetic nephropathy, hypertensive nephropathy,
However, maternal and fetal prognoses have improved recently systemic lupus erythematosus, and various connective tissue
due to better intensive care and neonatal resuscitation.84 The disorders.
diagnosis of gallstones is often confirmed with ultrasound. Kidney size is larger in pregnancy, mainly because of a 75%
Although the majority of women with acute cholecystitis are suit- increase in renal blood flow. There is dilation of the renal pelvis,
able for conservative management, the relapse rate is >33% and calyces, and ureter, more marked on the right side, probably due
surgery may be preferable. Complications of gallstones now repre- to a combination of hormonal factors and obstruction by the
sent the second most common nongynecological condition requir- gravid uterus. The glomerular filtration rate (GFR) increases
ing surgery during pregnancy, and cholecystectomy is performed from 100 to 150 ml/min by the second trimester causing a fall in
at a rate of 1“8 per 10 000 pregnancies. Endoscopic retrograde serum urea and creatinine. Hence, during pregnancy normal or
cholangiopancreatography may be required for common bile slightly raised serum urea and creatinine ( >80 mmol/l) indicate
duct stones. In the second trimester, cholecystectomy is associated poor renal function. Proteinuria increases slightly and tubular
with good maternal and fetal outcome, even when disease is reabsorption of glucose decreases, which contributes to the
severe.82,84,85 Lead shielding of the uterus minimizes fetal exposure development of gestational diabetes in some women. Tubular
to radiation and anesthetic management follows usual principles. reabsorption of bicarbonate also decreases, producing a compen-
The anesthetic issues with respect to placental perfusion and gas satory metabolic acidosis in response to the respiratory alkalosis
exchange during laparoscopic surgery with pneumoperitoneum seen in pregnancy. There is increased production of vitamin D,
have been reviewed.86,87 renin, and erythropoietin by the kidney, but their effects are
masked by other changes.
Primary biliary cirrhosis and primary sclerosing cholangitis
Primary biliary cirrhosis (PBC) is a rare disease with prevalence of
Chronic renal failure in pregnancy
1 in 13 000. It is diagnosed by detection of IgG antibodies to
mitochondrial pyruvate dehydrogenase, or by liver biopsy. The increase in GFR during pregnancy is attenuated with moder-
Histology shows slowly progressive destruction of intrahepatic ate renal impairment and lost with severe impairment. Chronic
bile ducts, portal inflammation, and scarring. Most patients are renal failure (CRF) is uncommon in pregnancy, occurring in
0.03“0.12% of all pregnancies in the USA.93 Chronic renal failure
women aged 35“60 years and infertility is common, so pregnancy



258
Chapter 14


Pathophysiology and causes of acute renal failure
Table 14.9 Maternal complications associated with chronic
in pregnancy
renal disease
Acute renal failure (ARF) in pregnancy is a rare event, having a
Preeclampsia
reported incidence of 1 in 10 000.1 Acute tubular necrosis and/or
Worsening renal function
renal cortical necrosis are associated with severe preeclampsia,
Preterm delivery
PPH, AFLP, or obstructive uropathy.92 Acute tubular necrosis
Anemia
(ATN) complicates many conditions, with severe uncorrected
Chronic hypertension
hypotension and preeclampsia the most common causes during
Cesarean delivery
pregnancy. The incidence of ATN in pregnancy has fallen drama-
tically due to the decline in septic abortion. Acute tubular necro-
sis occurs as a complication in 1“2% of women with severe
is defined as a progressive decrease in GFR and is mild when
preeclampsia, but usually there is full recovery of renal function.
the GFR > 50 ml/min, moderate if GFR is 10“29 ml/min, severe
Pregnant women are more predisposed to develop renal cortical
if GFR < 10 ml/min, and end-stage if the GFR < 5 ml/min.
necrosis. The main antecedents of renal cortical necrosis are
Diabetes mellitus and hypertension account for more than 50%
placental abruption, preeclampsia, and amniotic fluid embolism.
of cases of chronic renal failure in the general population. Severe
Hematuria is more common with renal cortical necrosis than
renal impairment or renal failure affects most body systems,
with ATN, and a larger proportion of women with renal cortical
mandating a thorough preoperative assessment.
necrosis never recover normal renal function.
In the woman with CRF symptoms, signs of hypertension and
Other causes of ARF include hemolytic uremic syndrome
accelerated atherosclerosis are common. The electrocardiogram
(HUS) and renal tract obstruction. Obstructive uropathy and
should be reviewed for signs of hyperkalemia (which may cause
nephrolithiasis are neither more common, nor more likely to be
ventricular dysfunction and acute dysrhythmias) and for QT pro-
complicated, during pregnancy, and urinary tract stones rarely
longation (which may reflect hypocalcemia). Hypoalbuminemia
cause ARF. Ureteric stenting or percutaneous nephrostomy can
and low plasma oncotic pressure predispose to the development
be used to relieve obstruction.
of pulmonary edema in the presence of fluid overload. A decrease
in surfactant production increases the risk of postoperative
atelectasis, and impaired response to infection increases the risk
Maternal and fetal outcome in renal disease
of pneumonia.
Maternal complications associated with chronic renal disease are
In CRF the concentrating ability of the kidney is impaired,
listed in Table 14.9. The live birth rate in women with chronic
leading to sodium and water retention. On the other hand, hypo-
renal disease ranges from 64“98% depending on the degree of
volemia may result from fluid loss secondary to pyrexia, vomiting,
renal insufficiency and presence of hypertension.93 Women with
or surgery. Hyperkalemia, hypermagnesemia, and chronic meta-
end-stage renal failure (serum creatinine > 170 mmol/l) often
bolic acidosis are common features. Intestinal absorption of cal-
experience amenorrhea or irregular menses, and are subfertile
cium is decreased and phosphate excretion is impaired, such that
or infertile, and are likely to have an increased rate of early
hyperphosphatemia develops, calcium is deposited in the soft
pregnancy loss and stillbirth. Renal function may deteriorate
tissues, and osteomalacia occurs. Glucose intolerance and dia-
from the physiological stresses of pregnancy, and 40% and 66%
betes mellitus are common. There is an increased risk of gastric
respectively of women with moderate or severe renal impairment
irritation and gastrointestinal hemorrhage. Nausea and vomiting
experience deterioration. A small proportion of those with mod-
are common problems in the uremic patient.
erate disease do not recover postpartum, but almost all women
Central nervous system manifestations, such as confusion or
with severe impairment have persistent deterioration and one in
convulsions, are late and sinister signs in CRF. Peripheral neuro-
three develop end-stage renal failure.
pathies should be documented preoperatively, especially prior to
Maternal and fetal outcomes depend on many factors includ-
a regional block, and there is the possibility of coexisting auto-
ing degree of renal dysfunction at conception; the underlying
nomic neuropathy.
disease process; and the degree of hypertension at conception
Normochromic normocytic anemia is a classic feature of CRF,
or in early pregnancy. Better outcomes occur in women with mild
although widespread use of recombinant erythropoietin has
renal dysfunction (serum creatinine <120 mmol/l) prior to preg-
decreased the severity of chronic anemia. The platelet count
nancy, with prepregnancy BP the most important prognostic
may be low or normal, and while standard coagulation tests are
factor. Patients with established hypertension are more likely to
often normal, bleeding time is frequently prolonged in uremic
patients, probably because of defective von Willebrand factor.96 experience disease progression and have worse fetal outcomes.
The incidence of preeclampsia among patients with mild
Abnormal bleeding in the acute setting can be treated with
renal disease is not greatly increased, but if serum creatinine
D-desmethyl-arginine vasopressin (DDAVP) and possibly recom-
is > 110 mmol/l the incidence is very high.
binant factor VIIa. Low serum albumin and metabolic acidosis
Maternal and fetal outcomes in pregnant women with renal
may increase the free-drug concentration of certain drugs. The
disease have been compared with matched controls with a high-
activity of drugs eliminated in part or largely by the kidneys is
risk pregnancy but no renal impairment.94 Women with renal
prolonged, mandating dose adjustment (see below).



259
4 Metabolic disorders


disease had higher BP during the first and third trimesters and a must be taken of arteriovenous fistulae. A fistula should be ban-
greater rate of pregnancy loss, mainly due to first trimester spon- daged and padded during childbirth or anesthesia. Intravenous
taneous abortion. The rate of premature delivery and C/S was catheters should be sited well away from a fistula, using the
similar in both groups. Diabetic patients had similar outcomes opposite limb whenever possible. Patients with osteomalacia
to controls, but those with hypertension had a poorer outcome, are prone to fractures, especially if the patient is under regional
and fetal loss was more common in the presence of autoimmune anesthesia, so careful attention to positioning and movement is
disease. Focal segmental glomerulosclerosis, IgA nephropathy, needed. Consideration must be given to the most appropriate
and reflux uropathy were associated with the worst outcomes setting for care after delivery. High-dependency care, where
among those with renal disease including a high rate of fetal close monitoring of fluid and electrolyte balance can continue,
loss. Only 3% of women with renal disease suffer deterioration is often required.
in renal function postpartum. Most of these have poor renal There is no evidence supporting additional benefits from regio-
function and severe hypertension at the time of conception, so nal blockade in pregnant patients with renal failure. Although an
deterioration usually reflects natural progression of the disease. epidural hematoma has been reported in a patient with chronic
renal failure,97 epidural analgesia is commonly used for patients
undergoing renal transplantation.98 Epidural insertion is gener-
Anesthesia for the pregnant woman
ally considered safe in renal patients, with the usual provisos
with renal failure
in relation to anticoagulants, such as low molecular weight
Patients with mild renal disease, normal renal function, and no heparin. It may be difficult to assess the coagulation status of
hypertension present no particular anesthetic concerns. In con- renal patients who present in labor or require urgent delivery,
trast, there are many anesthetic issues in women with end-stage as platelet count and coagulation tests are often normal.
renal failure, moderate to severe renal impairment, or those on Thromboelastography has been used in parturients with throm-
bocytopenia to assess global clotting function,99 although a risk“
dialysis. Such women should be identified as high risk early in
pregnancy and appropriate monitoring and management plans benefit assessment is required on an individual basis. Ideally,
established in close liaison with obstetric, nephrology, and patients with renal impairment should be identified early in
anesthetic colleagues. The literature is devoid of cases specifically pregnancy, providing time to perform specific tests and to obtain
discussing obstetric anesthetic considerations in the presence the opinion of a hematologist.
of renal disease, but the following general advice can be The maximum plasma concentration or time to peak concen-
applied.95,96 tration of bupivacaine is not significantly altered in patients with
renal failure.98 The onset of subarachnoid blockade may be faster,
Maternal intravascular volume must be assessed with a view to
maintaining BP, renal and placental perfusion. Large fluid or the dermatomal spread increased by one or two segments, but the
duration of the block is reduced.100 Possible explanations include
blood-volume loss may be poorly tolerated and central venous
pressure (CVP) monitoring should be considered. Arterial BP the effects of a hyperdynamic circulation and acidosis on the
monitoring is useful in cases where large blood loss is anticipated binding and pharmacokinetics of local anesthetics.
or occurs. Electrolyte disorders should be corrected.
Treatment of diabetes may require an insulin and dextrose
Specific renal diseases
infusion. Anemia should be sought and corrected, while taking
Urinary tract infection
care to avoid transfusion of patients who have adapted to low
hemoglobin levels. Renal patients are prone to delayed gastric Bacteruria is present in 3“7% of pregnant women and urinary
emptying, and full precautions against gastric aspiration are advi- tract infection (UTI) occurs in 25% of pregnancies. Acute pyelo-
nephritis complicates up to 1% of pregnancies.101 This is often
sable. Drugs that are primarily excreted by the kidneys should be
avoided, or the dosage altered (see Table 14.10). secondary to dilatation of the renal tract and urinary stasis.
Hypercarbia should be avoided because extracellular acidosis Women with recurrent UTI should be monitored closely with
causes intracellular potassium to move into the extracellular renal ultrasound. Prophylactic antibiotic therapy may reduce
compartment, potentially exacerbating hyperkalemia. In the further infections and preserve renal function. Preterm labor
may be triggered by UTI.102
presence of hypermagnesemia, nondepolarizing muscle relax-
ants are potentiated. Potassium release following the use of Pyelonephritis is often due to Escherichia coli and some women
succinylcholine is not increased in renal failure, but caution is present with septic shock, requiring intensive care. Other serious
necessary in those with hyperkalemia, as normal potassium complications include pulmonary edema, ARDS, hemolysis, and
release may evoke dysrhythmias. Uremia may disrupt the thrombocytopenia. It is postulated that low colloid osmotic pres-
blood“brain barrier, resulting in an exaggerated response to sure and plasma fibronectin concentration during pregnancy
induction agents. Patients with renal failure are more prone to may explain an apparent increase in vulnerability to pulmonary
complications.103
thrombosis, so antithrombotic therapy is frequently indicated.
Nonsteroidal anti-inflammatory drugs and other nephrotoxic A rare complication of obstruction and UTI is nontraumatic
rupture of the renal tract. In a series of 14 cases,104 eight had a
drugs should be avoided.
Renal patients are at increased risk of infection, so strict asepsis rupture of the collecting system and six had rupture of renal
is required when undertaking invasive procedures. Great care parenchyma. Patients complained of abdominal pain, most

<< . .

 51
( 87)



. . >>

Copyright Design by: Sunlight webdesign