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pituitary enlargement followed by atrophy and fibrosis. In its
may remain hypertensive despite significant intravascular fluid
most serious form, lymphocytic hypophysitis may lead to inade-
volume depletion due to DI.
quate corticotropin release with potential for adrenal insufficiency,
Central DI is treated with desmopressin (DDAVP), which can be
cardiovascular collapse, and death in the peripartum period. Other
given intranasally. Desmopressin is resistant to vasopressinase, is
presentations include headache or visual changes due to an enlar-
not uterotonic, and appears safe for the fetus and nursing
ging pituitary mass, or symptoms of specific hormonal deficits of
infant.49,50 Nephrogenic DI does not respond to DDAVP and is
thyrotropin, antidiuretic hormone, or gonadotropins. Lymphocytic
treated with the oral hypoglycemic, chlorpropamide. In all cases,
hypophysitis can be associated with postpartum thyroiditis.
adequate fluid resuscitation should be confirmed prior to induc-
Glucocorticoids are used to suppress the inflammatory response
tion of regional anesthesia or GA. Central intravascular monitor-
and protect remaining pituitary tissue. Steroids are important in
ing may be helpful in evaluating volume status.51 Plasma
cases of corticotropin deficiency and mass-related visual field def-
electrolytes and osmolarity should be evaluated, and a urinary
icits. Replacement doses of thyroxine, vasopressin, and gonadotro-
bladder catheter is recommended to monitor urine output.
pins may be necessary depending on symptoms and hormonal
Hypotonic fluids may be indicated in cases of extreme hyperos-
levels. Definitive diagnosis is by transsphenoidal biopsy.
molarity when the oral intake of free water is restricted. With
careful attention to volume status, electrolytes, and osmolarity,
Sheehan syndrome Sheehan syndrome occurs as a result
either general or regional anesthesia may be safely administered.
of ischemic pituitary necrosis due to severe postpartum
Epidural anesthesia for C/S in a woman with gestational DI and
hemorrhage. It is seen rarely without massive hemorrhage.
severe hypernatremia has been described.52
Improvements in obstetric care and blood-bank facilities have
been associated with a marked reduction in the incidence of
Sheehan syndrome in developed countries.56 The presentation
The syndrome of inappropriate antidiuretic
may include symptoms of DI, hypoadrenalism, hypothyroidism,
hormone secretion
hypoprolactinemia, and hypogonadism. Symptoms may develop
The syndrome of inappropriate antidiuretic hormone secretion as late as ten years following the initial obstetric event. Magnetic
(SIADH) is most commonly reported in older, critically ill, and resonance imaging is useful to look for an empty sella tursica;
postoperative patients with inadequately treated pain. One case however, an endocrinologic work-up is necessary to identify speci-
report describes a 32-year-old woman who developed SIADH on fic hormonal deficits. Although amenorrhea and infertility are com-
day five postpartum with symptoms of fatigue, weakness, dizzi- mon, spontaneous pregnancy may be possible if gonadal hormones
ness, and nausea.53 Other possible symptoms include weight are preserved. In such cases, appropriate thyroid and corticosteroid
gain, lethargy, confusion, seizure, and coma. Electrolyte testing replacement are essential for maternal and fetal well-being.57
demonstrates a serum sodium (Naþ) level < 130 mEq/l and serum
osmolality < 270 mEq/l. Therapy includes pain management and
Anesthetic considerations for women with
fluid restriction to < 800 ml per day.
panhypopituitarism
In the stable patient, a diagnostic evaluation under the guidance
of an endocrinologist will identify specific hormonal deficits and
Panhypopituitarism
replacement goals. In unstable patients, it may be necessary to
There are three major causes of panhypopituitarism in the peri- treat immediately with hydrocortisone, thyroxine, and fluid
partum period: iatrogenic, lymphocytic, and hemorrhagic. In resuscitation with careful monitoring of intravascular volume
addition, diabetic parturients with spontaneous pituitary necro- and electrolytes. Patients on corticosteroids will require supple-
sis may present with a midline headache, vomiting, and mentation during labor and delivery (hydrocortisone 100 mg
decreased insulin requirements. If unrecognized, the condition every eight hours). Regional and general anesthesia are safe pro-
may result in fetal and maternal death. vided there is adequate volume and hormonal replacement.



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Adrenal
Table 16.7 Syndromes associated with pheochromocytoma
Pheochromocytoma
Multiple endocrine neoplasia type 2A (Wermer syndrome)
Pheochromocytoma is rare during pregnancy, but can be life Pancreatic B-cell islet adenoma
threatening when it occurs. Symptomatic pheochromocytoma Pheochromocytoma
has an estimated prevalence of 20 per million pregnancies.58 Medullary thyroid carcinoma
Carcinoid syndrome
Multiple endocrine neoplasia and neuroectodermal Adrenal cortical adenoma
syndromes Pheochromocytoma is less rare among women with Multiple endocrine neoplasia type 2B (Sipple syndrome)
multiple endocrine neoplasia (MEN) or neuroectodermal syn- Mucocutaneous neuroma
dromes (see Table 16.7). Pheochromocytoma develops in 50% of Pheochromocytoma
patients with MEN 2A and 2B, in 25% of patients with von Hippel- Medullary thyroid carcinoma
Lindau syndrome (VHL), and in 5% of patients with neurofibro- Ganglioneuromas of visceral anatomic plexuses
matosis.59 Patients with familial pheochromocytoma are typically Von Hippel-Lindau syndrome
younger at diagnosis (32 versus 46 years), and are more likely to Ataxia telangiectasia syndrome
develop multifocal disease (55% versus 8%), and malignancy Neurofibromatosis (von Recklinghausen syndrome)
(11% versus 0%).60 In one series of 82 patients with pheochromo- Tuberous sclerosis
cytoma, 23% were carriers of familial disorders, so all patients Sturge-Weber syndrome
with pheochromocytoma should be screened for associated
genetic disorders.60 Genetic testing is becoming available with
specific mutations identified in the RET gene (seen with some presence of a presumptive diagnosis of preeclampsia should
point towards pheochromocytoma.66
forms of MEN 2), the VHL tumor-suppressor gene, the NF 1 gene
(neurofibromatosis type I), and various succinate dehydrogenase If hypertension is paroxysmal, the patient may present with
subunits (pheochromocytoma-paraganglioma syndromes).59 symptoms other than hypertension, including episodic head-
Patients and family members who test positive for one of these aches, pallor, palpitations, excessive sweating, spells of anxiety,
oncogene mutations may be candidates for prophylactic therapy. tremor, fatigue, glucose intolerance, or dizziness due to orthostatic
hypotension.67 Finally, myocardial injury is a well-recognized
For example, in families with MEN 2 A, the RET mutation identifies
children at risk for medullary thyroid cancer who will benefit from complication of pheochromocytoma. Case reports have described
prophylactic total thyroidectomy.61 women who presented with pulmonary edema and acute cardiac
failure where peripartum cardiomyopathy, myocardial ischemia,
Maternal and fetal outcomes of pheochromocytoma or pulmonary embolus were considered before pheochromo-
cytoma was diagnosed.68,69,70 Cardiogenic shock requiring pressor
Historically, maternal and fetal mortality rates were 58% and
61% respectively.62 The most common causes of maternal death support may develop following massive catecholamine release
followed by catecholamine failure.70 Other medical conditions
were cardiovascular collapse, cardiac arrest, dysrhythmia, and
intracerebral hemorrhage. Uteroplacental insufficiency leads that mimic pheochromocytoma include abdominal catastrophe,
cerebral hemorrhage, epilepsy, eclamptic seizure,71 cocaine or
to spontaneous abortion, IUGR, fetal hypoxia, and intrauterine
fetal death. More recently, antenatal diagnosis and medical other sympathomimetic drug abuse, sepsis, MH, acute adrenal
insufficiency, and thyrotoxicosis.72 Nephrolithiasis may develop
management of pheochromocytoma have improved outcomes.
When antenatal diagnosis and medical management with alpha- as a result of dehydration.
adrenergic blockade are successful, maternal mortality may Because pheochromocytomas secrete heterogeneous patterns
be reduced to zero and fetal mortality to 15% to 20%.63,64 of catecholamines and catecholamine metabolites, no single bio-
Nevertheless, maternal and neonatal deaths continue to occur,65 chemical analysis is perfectly accurate. The availability of labora-
with two maternal deaths attributed to pheochromocytoma in The tory testing varies by center, and the appropriate testing strategy
Sixth Report of the Confidential Enquiries into Maternal Death in varies based on family history and patient presentation.
the United Kingdom 2000“2002.66 Therefore, consultation with a clinical pathologist is recom-
mended prior to ordering diagnostic tests for pheochromocytoma.
Clinical features However, the combination of resting plasma catecholamines
Prenatal diagnosis is the most important step in minimizing (norepinephrine and epinephrine) > 2000 pg/ml and urinary
maternal and perinatal mortality. In the setting of pregnancy, metanephrines (normetanephrine and metanephrine) > 1.8 mg
the diagnosis can be missed because symptoms are often attrib- in a 24-hour urine collection has a diagnostic accuracy of 98%
for both sporadic and hereditary pheochromocytoma.73 An alter-
uted to severe preeclampsia. Hypertension is the most common
sign of pheochromocytoma, occurring in 98% of cases,64 but native screening strategy is to measure fractionated plasma meta-
episodes of hypertension may be either chronic or paroxysmal nephrines only, which have a sensitivity of 97% and a specificity
and transient. A multigravid woman with severe hypertension of 96% among those with a familial endocrine syndrome. For the
and no previous history of preeclampsia should prompt investi- general population, sensitivity is also high (99%), but specificity
gation for pheochromocytoma. In addition, glycosuria in the is only 82%, so a positive test should be followed up by more



283
4 Metabolic disorders


complete testing.74 For women with indeterminate biochemical
Table 16.8 Criteria for optimal preoperative preparation in
results, a provocative test with glucagon or a suppression test with
pheochromocytoma
clonidine may help to distinguish patients with pheochromocytoma
from those patients with essential hypertension or preeclampsia. No BP higher than 160/90 mmHg in the 24 hours prior to surgery
However, each has the potential of inducing hemodynamic instabil- Orthostatic hypotension should be present, but not less than
ity, and their use in pregnancy has been questioned. 80/55 mmHg
Once the diagnosis is confirmed biochemically, radiological The electrocardiograph should be free of ST-T segment changes
evaluation may be used to locate the tumor. Magnetic resonance Premature ventricular contractions should be no more frequent than
imaging, CT and 123Iodinated metaiodobenzylguanidine (123I- once every 5 minutes
MIBG) scans all have excellent sensitivity (95“100%), but MRI Hematocrit decreased by $5%
avoids ionizing radiation.73 Ultrasound is a less sensitive alter-
native. Although most tumors are located in the adrenal medulla, Adapted from Roizen M. F., Schreider, B. D. & Hassan, S. Z. Anesthesia
approximately 10% can be found in the sympathetic ganglia for patients with pheochromocytoma. Anesthesiol. Clin. North Am.
located along the superior and inferior paraaortic areas, the 1987; 5: 269“75.
bladder, thorax, head, neck, or pelvis.
Finally, if cardiomyopathy or CHF is suspected, echocardiogra-
phy will define the extent of any cardiac dysfunction.
allowed for a relatively stable hemodynamic course throughout
delivery.67
Management
Initial management is directed at controlling the hemodynamic The pregnant woman with an unresected pheochromocytoma
response to catecholamines. Phenoxybenzamine, a long-acting is usually scheduled for a planned C/S. Preoperative preparation
a-blocker, is given orally (10 mg twice daily and increased by with 10 to 14 days of phenoxybenzamine therapy may be needed
10 mg/day until symptoms are controlled). Prazosin (1.5“2.5 mg to achieve adequate a-blockade. Concomitant oral hydration will
q 6 h) or doxasocin (2“16 mg/day) are equally effective, and may help expand the intravascular volume.
have fewer side effects than phenoxybenzamine.75,76 Labetalol Criteria for adequate preoperative preparation in the nonpreg-
may be added if tachycardia persists, but should not be given nant patient are listed in Table 16.8. In pregnancy, the BP goal
until a-blockade is established. Calcium channel blockers have of < 160/90 mmHg may represent inadequate preparation, and a
also been used. more appropriate goal may be 10“15 mmHg below this value.
Once hemodynamic control is achieved, management varies by Furthermore, orthostatic hypotension may not be advisable
gestational age. Before 24 weeks™ gestation, patients may have because it may impair uteroplacental perfusion and contribute
surgical resection of the pheochromocytoma through an open to oligohydramnios. The FHR pattern should be monitored regu-
or laparoscopic approach.77 After 24 weeks™ gestation, patients larly while increasing the dose of antihypertensive medication.83
are typically managed medically with phenoxybenzamine or Patients with pheochromocytoma accumulate norepinephrine
another a-adrenergic antagonist until the fetus matures, at in their nerve terminals, and develop an exaggerated sympathetic
which time, open surgical resection may be combined with C/S. response when stress and pain stimulate norepinephrine release.
One case described the conservative management of pheochro- Therefore, attention to anxiolysis and analgesia is important.
mocytoma from 14 to 35 weeks™ gestation, with delivery by C/S. Preoperative sedation with a low dose of benzodiazepine reduces
Three weeks later, tumor removal and total hysterectomy were maternal anxiety and activation of the sympathetic nervous sys-
performed.78 tem. Intraoperative analgesia with a sufentanil infusion helps to
control the physiologic response to pain.84 Alternatively, regional
Plasma catecholamines are largely metabolized by placental
catechol-O-methyl transferase and monoamine oxidase, with anesthesia with an epidural catheter may control the exaggerated
minimal transfer to the fetus.79 In contrast, phenoxybenzamine physiologic response to pain.
crosses the placenta and appears to accumulate in the fetus. The Both epidural anesthesia and GA are appropriate as long as care
fetal to maternal plasma phenoxybenzamine ratio has been meas- is taken to monitor and treat hemodynamic lability. Monitors
ured at between 1.13:1 and 1.6:1.80 Neonates exposed to long- include ECG, pulse oximetry, urinary bladder catheter, and arterial
term phenoxybenzamine may experience hypotension and line. A second, large-bore peripheral i.v. cannula (14- or 16-gauge)
respiratory distress in the first few days of life.81 is established to allow for rapid infusion of warmed crystalloid
and colloid fluids intraoperatively. It may be prudent to place a
Obstetric and anesthetic considerations central access sheath preoperatively, in case catecholamine-
The preferred mode of delivery is C/S because uterine contrac- induced cardiomyopathy becomes apparent intraoperatively.
tions and the maternal Valsalva maneuver may precipitate cate- When GA is used, care must be taken to minimize the hemo-
cholamine release. However, there are case reports of uneventful dynamic effects of intubation. Alfentanil (20“30 mg/kg) or fentanyl
vaginal deliveries among women with pheochromocytoma.67,82 (2“3 mg/kg) and lidocaine (1“2 mg/kg) will reduce the incidence of
In one case, dense epidural anesthesia, minimal maternal push- ventricular dysrhythmias and prevent or attenuate the pressor
ing, vacuum-assisted delivery, manual delivery of the placenta, response to endotracheal intubation. These drugs are followed
and ongoing hemodynamic monitoring and management immediately by induction with 4 mg/kg sodium thiopental or



284
Chapter 16


retain Kþ, leading to hyponatremia and hyperkalemia. Adrenal
0.3 mg/kg etomidate with 1.5 mg/kg succinylcholine. Rocuronium
is preferred to succinylcholine if the tumor is embedded in skeletal insufficiency may occur as a result of pituitary or adrenal failure
muscle. Controlled ventilation with a mixture of nitrous oxide, or destruction.
oxygen, and isoflurane is acceptable for maintenance of GA. Primary adrenal insufficiency in the perinatal period may result
Drugs that release histamine, such as atracurium and morphine, from intrapartum hemorrhage, traumatic breech delivery, or ful-
minant sepsis.89 Autoimmune adrenal insufficiency occurs at a
are avoided, because histamine stimulates catecholamine release
from chromaffin granules. Droperidol and metoclopramide should rate of 2“3 in 100 000 as an isolated abnormality or as a part of an
also be avoided as they may block inhibitory dopaminergic input to autoimmune polyglandular deficiency syndrome (types I and II).
chromaffin cells. In type II, women aged 20 to 40 years have chronic immune
thyroiditis and insulin-dependent diabetes mellitus.90,91
Regional anesthesia with a lumbar epidural catheter has been
used successfully for C/S and pheochromocytoma resection. In Other patient scenarios that may lead to mineralocorticoid
the presence of sympathetic blockade with epidural anesthesia, insufficiency include prolonged administration of corticoster-
oids, congenital 21-hydroxylase deficiency,92 and acquired
postsynaptic receptors still respond to the direct effects of cate-
immunodeficiency syndrome.93 The antifungal drug ketocona-
cholamines. Epinephrine should be removed from the test dose
solution. Possible problems with this technique include hypoten- zole may cause adrenal insufficiency because it inhibits mito-
sion following tumor vein ligation, and inadequate anesthesia if chondrial cytochrome P450 enzymes such as cholesterol
high abdominal exploration is required. An alternative anesthetic desmolase, 11 ß-hydroxylase, and aldosterone synthase.
strategy is to use lumbar epidural anesthesia for the C/S followed
by GA for the pheochromocytoma resection.83 With either a re- Clinical features
gional or a GA technique, periods of paroxysmal tachycardia and With Addison disease, chronic primary adrenal insufficiency
hypertension should be expected before tumor resection, and presents with an insidious history of malaise, anorexia, diarrhea,
profound hypotension can occur after the tumor is removed. weight loss, joint and back pain. The cutaneous manifestations
Therefore, short-acting vasoactive infusions should be prepared include darkening of the skin especially in sun-exposed areas and
for intraoperative hemodynamic management. hyperpigmentation of the palmar creases, frictional surfaces,
recent scars, genital skin, and oral mucosa.88 Hyponatremia,
Sodium nitroprusside (SNP, 50 mg in 500 ml of 5% dextrose
solution) can be infused to control BP intraoperatively (1 mg/kg/ hyperkalemia, and volume depletion typify aldosterone insuffi-
min). If the surgery includes removal of the pheochromocytoma, ciency. Because nausea, vomiting, fatigue, weakness, and hyper-
SNP should be terminated when the adrenal vein is clamped. pigmentation are common symptoms of pregnancy, the
Typically, recovery from the SNP infusion occurs within two diagnosis of adrenal insufficiency may be difficult. Clinical and
minutes, thus preventing a rapid fall in BP once the tumor is laboratory features of adrenal insufficiency indicate deficiencies
removed. Fetal cyanide toxicity can become a problem if higher in cortisol and aldosterone. Plasma cortisol levels and cortisol-
doses are used or maternal tachyphylaxis develops. binding globulin levels are increased during normal pregnancy,
Magnesium sulfate (4 g i.v. loading dose, 1 g/h i.v. infusion, but patients with Addison disease fail to show the expected rise
2 g i.v. bolus p.r.n.) helps maintain cardiovascular stability during in cortisol following adrenocorticotrophic hormone (ACTH)
pheochromocytoma resection.85 Magnesium sulfate has a direct stimulation.
vasodilator effect, reduces the sensitivity of the alpha-adrenergic
Maternal and fetal effects
receptors to catecholamines, and inhibits release of catechola-
mines from the adrenal medulla and peripheral adrenergic nerve Historically, Addison disease was associated with a high rate of
terminals. Magnesium has been used to treat the symptoms maternal mortality but today, with adequate steroid replacement,
associated with pheochromocytoma crises.86 Magnesium has pregnancy is associated with minimal risk.94,95 Overall prognosis
the additional benefit of being familiar to obstetric care provi- for the fetus and newborn is good, although there are reports of
ders.87 If magnesium is used, blood levels should be checked and oligohydramnios, IUGR, and fetal distress.96
neuromuscular function carefully monitored as recovery may be
Management
impaired.
Other useful vasoactive medications include: phentolamine Standard doses of glucocorticoids (hydrocortisone 20“30 mg/
IV bolus (1“5 mg), nitroprusside IV bolus (1“2 mg/kg), esmolol, labe- day) and mineralocorticoids (fludrocortisone 0.05“0.10 mg/day)
talol, and propranolol. Following resection, hypotension unrespon- are used during pregnancy. Most women tolerate labor and vagi-
sive to volume expansion with crystalloids or blood may be treated nal delivery well, but the potential for Addisonian crisis must be
with an infusion of epinephrine, norepinephrine, or phenylephrine. recognized. Fluid balance, glucose, and electrolyte levels should
Avoid using indirect sympathomimetics such as ephedrine. be optimized, and stress-dose steroids considered, particularly in
cases of operative delivery.

Addison disease
Anesthetic implications
Addison disease, or primary adrenal insufficiency, results in Current techniques of epidural analgesia or GA may be used when
glucocorticoid and mineralocorticoid deficiency.88 Patients with appropriate. Certain modifications are recommended for GA.
this disorder excrete excessive amounts of Naþ in the urine but Administration of incremental or low doses of anesthetic agents



285
4 Metabolic disorders


is recommended to avoid the risk of drug-induced myocardial tacrolimus, and other calcineurin inhibitors may also cause aldos-
depression. Etomidate should be avoided because of the potential terone resistance mediated by a reduction in mineralocorticoid
receptor expression.98
transient inhibition of cortisol synthesis. A peripheral nerve sti-
mulator allows monitoring of neuromuscular blockade and titra- There are no reports of this condition in pregnancy.
tion of neuromuscular blocking agents, because skeletal muscle
weakness is a typical feature of the disease. In cases of emergency
Cushing syndrome
surgery, hydrocortisone 100 mg may be administered every
6 hours for 24 hours. Invasive hemodynamic monitoring has Cushing syndrome is produced by any condition associated with
been used to guide volume replacement. It is important to excessive cortisol production. Cushing disease is the term used
remember the potential for Addisonian crisis, hypotension, and when a pituitary tumor produces excessive amounts of ACTH.
circulatory collapse. Pregnancy in patients with Cushing syndrome is rare because
of infertility from anovulation, or from maternal complications
Addisonian crisis Addisonian crisis is a life-threatening condi- such as hypertension, gestational diabetes, spontaneous abortion,
tion that may be precipitated by the stress of labor and delivery, and preeclampsia.100 Cushing syndrome has been separated
infection, or surgery. It may occur at any time during the peri- into two categories: (1) adrenal corticotropin hormone-dependent,
partum period. Common presenting symptoms include abdom- which is associated with excessive plasma corticotropin con-
inal pain, nausea, vomiting, and shock, which can be confused centrations, stimulating the adrenal cortex to produce markedly
with an acute surgical emergency within the abdomen. elevated cortisol levels; and (2) corticotropin-independent, which
Circulatory collapse in Addisonian crisis has several possible is associated with excessive production of cortisol by abnormal
mechanisms: loss of an enhanced response to catecholamines adrenocortical tissue that suppresses the secretion of both corti-
linked to steroids, altered receptor affinity, increased catechola- cotropin-releasing hormone (CRH) and corticotrophin.101 A 1990
mine metabolism, increased calcium (Ca2þ) uptake and altered literature review reported 58 pregnant women with Cushing
electrolyte milieu, loss of cardiac glycogen, and decreased ade- syndrome. A benign adrenal adenoma was present in 40%, adrenal
nosine triphosphatase activity. In addition, reversible car- hyperplasia due to elevated ACTH of either pituitary or placental
diomyopathy has been described in a patient with Addison origin in 41%, and carcinoma in 10%. In four cases, the cause
disease.97 was undetermined, and one patient had ectopic ACTH from an
It is important to remain alert to this possibility in the undiag- ACTH-secreting pheochromocytoma.102
nosed patient with Addison disease. Therapy includes a bolus
of 100 mg hydrocortisone followed by 300“400 mg of i.v. hydro-
Clinical features
cortisone infused over 24 hours.
The typical features include weight gain, weakness, muscle atrophy,
abdominal striae, easy bruising, edema, hyperpigmentation, thin-
Pseudohypoaldosteronism ning of the skin, pathologic fractures, and abnormal glucose toler-
ance. The diagnosis may be delayed or missed if signs and
Pseudohypoaldosteronism (PHA) type I is a class of genetic dis-
symptoms are attributed to normal pregnancy, preeclampsia, or
orders characterized by elevated serum levels of aldosterone and
diabetes mellitus.100
aldosterone resistance. The autosomal recessive form is more
Biochemical diagnosis may be problematic because cortisol
severe. Infants typically present in the first two weeks of life with
levels are elevated two- to three-fold during normal pregnancy,
weakness, failure to thrive, hyponatremia, hyperkalemia, and
and much of this is protein bound. Pregnant women with
metabolic acidosis, and require sodium chloride and Kþ binding
Cushing syndrome may be identified because they typically
resins throughout life to maintain electrolyte homeostasis.98 The
lose the normal diurnal variation in cortisol levels and have
autosomal recessive form is caused by a loss-of-function mutation
increased urinary free cortisol.103
in the gene encoding the endothelial Naþ channel, the primary
Patients with corticotropin-dependent Cushing syndrome
mediator of aldosterone-dependent Naþ transport in the distal
show significant suppression of free cortisol and 17-hydroxycor-
nephron, colon, sweat glands, and salivary glands. In addition to
ticosteroid levels following a dexamethasone suppression test. In
electrolyte derangements, patients suffer from pulmonary conges-
contrast, patients with corticotropin-independent Cushing syn-
tion, wheezing, and secondary pulmonary infections. Autosomal
drome fail to demonstrate suppression of baseline corticosteroid
dominant PHA type I is caused by mutations in the gene that
levels. Ultrasonography, MRI, or CT may be helpful in locating an
encodes the mineralocorticoid receptor. Sodium chloride and Kþ
adrenal or pituitary mass or bilateral adrenal hyperplasia.
binding resins may be necessary in infancy, but symptoms subside
in childhood. Adult survivors continue to show marked elevations
Maternal and fetal effects
in aldosterone, but require no therapy, maintain normal elec-
trolytes and BP, and have normal pulmonary function.99 Cushing syndrome has significant morbidity and mortality for
mother and fetus.102 In a series of 67 pregnancies, 46% had preterm
Pseudohypoaldosteronism type II (Gordon syndrome) is an auto-
somal dominant disorder that causes hypertension and hyperka- births, 12% spontaneous abortions, 7% stillbirths, and 34% term
lemia in the presence of a normal glomerular filtration rate (GFR), births. Other complications include IUGR, fetal hypertrophic
and serum aldosterone levels remain low or normal.98 Cyclosporin, cardiomyopathy,104 and neonatal adrenal insufficiency. Maternal



286
Chapter 16


complications include hypertension (65“87%), glucose intolerance complications, such as cardiac failure. For GA, consider awake
(32“61%), CHF (11%), impaired wound healing (8“40%), pulmon- fiberoptic intubation because central obesity, a buffalo hump,
ary embolism, and maternal death (4.5%).102,105 Other compli- increased fatty tissue of the neck and sternal areas, and delicate
mucosa may all contribute to a difficult airway.109,112 Muscle weak-
cations of Cushing syndrome in pregnancy include HELLP
syndrome, preeclampsia, and multiple pathologic fractures.106 ness may reduce the dose requirements for neuromuscular block-
ing agents, and a peripheral nerve stimulator is essential for GA
Management with pharmacologic paralysis.
Management during pregnancy may include unilateral or bilat- If severe hypertension is present on arrival in the operating
eral adrenalectomy, pituitary irradiation, pituitary adenectomy, room, hydralazine or labetalol is used and BP is reduced to a
or medical therapy with metyrapone or cyproheptadine. These range of 140“150 mmHg systolic and 90“100 mmHg diastolic.
interventions are associated with fewer premature births and Before induction of GA, a diastolic BP can be maintained at 90
stillbirths compared with supportive therapy alone.105 Hence, to 100 mmHg using 50-mg boluses of nitroglycerin (50“200 mg).
surgery is the definitive and preferred treatment for women with After cord clamping, intravenous opioids reduce the release of
severe symptoms. Surgery was traditionally performed at the end cortisol secondary to surgical stimuli.
of the first or beginning of the second trimester, but there now are
reports of laparoscopic and open adrenalectomy in the second
Conn syndrome
and third trimesters.107,108 Transsphenoidal hypophysectomy has
been used successfully in mid-pregnancy for a woman with In primary hyperaldosteronism (Conn syndrome), excess minera-
Cushing disease.109 This case was complicated by patient obesity locorticoid secretion produces diastolic hypertension, hyper-
requiring awake fiberoptic intubation, diabetes with decreasing natremia, hypokalemia, kaliuresis, and metabolic alkalosis.
postoperative insulin requirements, and hypertension.109 Symptoms include headache, fatigue, weakness, and muscle
Women who are not surgical candidates, or whose diagnosis is cramps. Primary hyperaldosteronism is rare in pregnancy, with 29
made later in pregnancy may be treated with metyrapone,110 the cases reported in the literature up to 2002.113 Patients present with
5-HT antagonist cyproheptadine, or ketoconazole,111 all of which hypertension resistant to therapy, and may develop uteroplacental
inhibit cortisol secretion. Each medication crosses the placenta insufficiency resulting in premature delivery, placental abruption,
and may cause fetal adrenal suppression. The risk for teratogeni- IUGR, or intrauterine fetal demise. Of 27 women with completed
city is unclear based on current evidence. Medical treatment is pregnancies, 85% had hypertension ( > 140/90 mmHg), 52% had
continued until the fetus is mature, at which time early delivery proteinuria, 44% delivered prematurely, and 7% experienced an
intrauterine fetal death.113 Other potential complications include
may be chosen depending on maternal and fetal status.
CHF, aortic dissection, dysrhythmias secondary to hypokalemia,
Anesthetic implications hyperglycemia, hypercoagulability with thromboembolism, and
It is important to evaluate coagulation, cardiovascular function, pathologic fractures. Most cases are due to an adrenal adenoma

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