Oncologic emergencies Flashcards
(166 cards)
1
Q
What are the historical classifications of neutropenia based on ANC levels?
A
Mild: 1000 to 1500 cells/mm3, Moderate: 500 to 1000 cells/mm3, Severe: less than 500 cells/mm3.
2
Q
How is the ANC calculated?
A
([ % granulocytes] + [ % bands]) × [total WBC count] / 100.
3
Q
What is the mortality risk associated with neutropenic fever?
A
About 10% of hospitalized patients will not survive to discharge.
4
Q
What are the most common causes of neutropenic fever?
A
- Pneumonia
- Anorectal lesion
- Skin infection
- Pharyngitis
- Urinary tract infection.
5
Q
What is the definition of fever in neutropenic patients?
A
A single temperature of 38.3°C or greater or a sustained temperature of 38.0°C or greater for 1 hour or more.
6
Q
Is fever a requisite for infection in neutropenic patients?
A
No, any neutropenic patient with signs or symptoms of infection should be treated as having neutropenic fever.
7
Q
What should the history and physical examination for neutropenic patients include?
A
- Diarrhea
- Nausea or vomiting
- Headache
- Neck stiffness
- Rashes
- Dysuria
- Cough
- Dyspnea
- Pain at any location.
8
Q
What risk does an indwelling venous catheter pose in neutropenic patients?
A
Increases the risk of bacteremia and skin infection.
9
Q
What is a common adverse effect of chemotherapy that can provide a portal for oral flora into the bloodstream?
A
Mucositis.
10
Q
What are some differential diagnoses for fever in cancer patients?
A
- Infection
- Venous thrombus or embolus
- Adverse effect of chemotherapy or other medication
- Direct effect of tumor burden.
11
Q
What percentage of neutropenic fever cases have a clear source of infection identified?
A
Only about one-third.
12
Q
What should all febrile neutropenic patients receive?
A
Empirical antibiotics and a full evaluation for an infectious source.
13
Q
What percentage of hematologic malignancies experience neutropenic fever at least once during therapy?
A
Up to 80%.
14
Q
What percentage of solid tumors experience neutropenic fever during chemotherapy?
A
10-50%.
15
Q
What does survival rate in neutropenic fever hinge upon?
A
Expeditious recognition and appropriate treatment.
16
Q
What is the IDSA definition of neutropenic fever?
A
Single temp ≥ 38.3°C or sustained temp ≥ 38°C for more than 1 hour with ANC of either < 0.5 or < 1 with a predicted nadir of < 0.5 over subsequent 48 hours.
17
Q
Multinational Association of Supportive Care
in Cancer (MASCC) Risk Index
A
18
Q
Clinical
Index of Stable Febrile Neutropenia (CISNE)
A
19
Q
What should be done for neutropenic patients with fever before administering antibiotics?
A
At least two sets of blood cultures should be drawn
Both cultures may be drawn peripherally in patients without central access. In patients with a central line, one culture should be peripheral and others from each lumen of the central catheter.
20
Q
What indicates a possible catheter-associated infection in blood cultures?
A
Bacterial growth in the catheter-drawn samples greater than 2 hours prior to the peripheral samples
This suggests that the infection may be associated with the catheter.
21
Q
What tests should be performed for patients with neutropenic fever?
A
CBC with differential count, urinalysis, urine culture, chemistries, renal and hepatic function tests
Serum lactate should also be measured if sepsis is suspected.
22
Q
What additional cultures may be sent based on clinical presentation in neutropenic patients?
A
Sputum culture, stool culture, testing for Clostridium difficile
These tests are relevant if there are specific symptoms like productive cough or diarrhea.
23
Q
What is the initial imaging usually performed for neutropenic patients with fever?
A
Chest x-ray
This imaging is often low-yield in the absence of specific respiratory symptoms.
24
Q
What should be considered if fever persists for 72 hours without an identified source?
A
Empirical CT scan of the chest and sinuses, and bronchoalveolar lavage
This is to evaluate for occult fungal infection.
25
Who is at higher risk of fungal pneumonia in the context of neutropenic fever?
Patients with a history of invasive aspergillosis and those with profound or prolonged neutropenia
## Footnote
Pulmonary imaging should be considered for these patients if there is little clinical response within the first day of therapy.
26
When may directed CT scans be performed sooner?
In the setting of appropriate clinical signs
## Footnote
For example, chest CT for coughing and bronchial breath sounds despite a clear chest x-ray.
27
What is the role of nucleotide sequencing in pathogen identification?
It is being developed as a useful adjunct for pathogen identification
## Footnote
Although it may direct antibiotic therapy prior to culture growth, it should not replace conventional diagnostics.
28
What should febrile neutropenic patients receive prior to confirmation of an infectious source?
Antibiotics
## Footnote
This is crucial for managing febrile neutropenia effectively.
29
What are high-risk features for febrile neutropenic patients according to IDSA?
* Expected duration of neutropenia greater than 7 days
* Expected nadir ANC less than 100 cells/mm3
* Hypotension
* Pneumonia
* New-onset abdominal pain
* Neurologic changes
* Significant medical comorbidities
* Current or prior infection with a resistant organism
* Treatment at a center with a high prevalence of resistant organisms
30
What scoring system identifies low-risk patients based on clinical features?
Multinational Association for Supportive Care in Cancer (MASCC) risk index
## Footnote
Patients scoring at least 21 points are considered low-risk.
31
What is the recommended antibiotic regimen for high-risk febrile neutropenic patients?
Parenteral broad-spectrum antibiotic regimen
## Footnote
Monotherapy using a broad-spectrum beta-lactam with antipseudomonal coverage is typically recommended.
32
Name some broad-spectrum beta-lactams recommended for high-risk febrile neutropenic patients.
* Ceftazidime
* Cefepime
* Piperacillin-tazobactam
* Antipseudomonal carbapenem
33
True or False: Combination therapy with aminoglycosides provides a survival benefit for febrile neutropenic patients.
False
## Footnote
A meta-analysis showed no survival benefit and increased adverse events with aminoglycosides.
34
What should be considered when choosing specific agents for antibiotic therapy?
Local antibiograms
## Footnote
This helps tailor the antibiotic regimen to local resistance patterns.
35
What is the recommended empirical therapy for patients with community-acquired pneumonia?
* Levofloxacin 750 mg IV q24 hrs
* Azithromycin 500 mg IV q24 hrs
* Doxycycline 100 mg q12 hrs
36
What is the preferred regimen for Pneumocystis pneumonia (PCP) coverage?
Trimethoprim-sulfamethoxazole (TMP-SMX) at 15 to 20 mg of TMP per kg per day IV
## Footnote
Dosing must be divided into 3 or 4 doses per day.
37
What should be done for patients with gastrointestinal symptoms?
Cefepime/metronidazole combination therapy
## Footnote
This has shown improved 28-day survival compared to piperacillin-tazobactam monotherapy.
38
What is the initial regimen for patients with herpes infections?
Acyclovir 5-10 mg/kg IV every 8 hours
## Footnote
Dosing must be adjusted for renal impairment.
39
What are some strategies to reduce time to antibiotics in the ED setting?
* Implementation of neutropenic fever order sets
* Dedicated neutropenic fever response team
* Elevation of patients in triage queue
* Protocol for bedside initiation of antibiotics
40
What enteral regimen may low-risk patients be treated with?
* Amoxicillin/clavulanate (875 mg PO q12 hrs)
* Fluoroquinolone (e.g., ciprofloxacin 500 mg PO q12 hrs)
41
What are the criteria for outpatient treatment of febrile neutropenic patients?
* MASCC score of 21 or less
* No evidence of pneumonia, line infection, cellulitis, or organ failure
* Reliable daily follow-up with oncologist
* Clinical stability during observation in ED for 4 hours or longer
* Low suspicion of infection with a drug-resistant organism
42
What should be ensured before discharge of febrile neutropenic patients?
* Initial dose of parenteral antibiotics in the ED
* Reliable follow-up and access to outpatient antibiotic regimen
* Coordination of discharge with oncologist
43
What is the mortality rate for high-risk infections in neutropenic fever?
30-90%
44
Name two high risk infections in neutropenic fever?
1. Neutropenic Enterocolitis or Typhilitis(Involves cecum, generally occurs 10-14 days post chemo)
2. Zygomycosis or Mucormycosis( involves paranasal sinuses, Infection of fungal hyphae into vasculature, rapidly leading to tissue necrosis and destruction)
45
What are the common symptoms of neutropenic enterocolitis?
Fever, RLQ pain, nausea, vomiting
46
What complications can arise from rhinocerebral mucormycosis?
Encroaching into orbits, oro-nasopharynx, brain, nearby vasculature
47
What does a MASCC Score of 21 or higher indicate?
Identifies low-risk patients
48
What are the positive predictive value (PPV), sensitivity, and specificity for the MASCC Score?
PPV 94%, sensitivity 80%, specificity 71%
49
What antibiotics resulted in successful outpatient treatment for 96% of cases?
Ciprofloxacin and amoxicillin-clavulanate
50
What is the primary cause of metastatic spinal cord compression (MSCC)?
Malignancy-related compromise of the spinal cord due to an extradural neoplasm that has metastasized to the vertebral column.
## Footnote
The lesion expands to invade spinal canal locally from the marrow space through a vertebral vein foramen.
51
Is direct nerve compression by tumor common in MSCC?
No, direct nerve compression by tumor is uncommon.
52
What is the more common cause of cord injury in MSCC?
Occlusion of the epidural venous plexus leading to breakdown of the blood-cord barrier and vasogenic edema.
Untreated tumor expansion leads to Arterial obstruction, causing cord ischemia and infarcta
53
What are less common causes of cord injury over time in MSCC?
Direct compression of the cord leading to demyelination and axonal injury.
54
Which tumors most commonly cause MSCC?
* Prostate cancer
* Breast cancer
* Lung cancer
## Footnote
Each accounts for about 15% to 20% of total cases.
55
What additional cancers account for 5% to 10% of MSCC cases?
* Renal cell cancer
* Non-Hodgkin lymphoma
* Multiple myeloma
56
What is the most commonly affected region in MSCC cases?
Thoracic spine (60%).
## Footnote
* Lumbosacral spine: 25%
* Cervical spine: 15%
57
What percentage of patients with MSCC have multiple loci of spinal metastasis?
Twenty to forty percent.
58
What are the most frequent presenting symptoms of MSCC?
* Back pain(most common initial symptom, occurs in more than 95% of patients)
* Weakness ( extremity weakness occurs in up to 75% of patients)
* Sensory loss
* Autonomic function loss
59
What differential diagnoses should be considered in patients with back pain?
* Muscle strain
* Ligamentous sprain
* Pathologic fracture
* Disc displacement
* Radicular stenosis
* Vertebral osteoarthritis
* Paraspinal infections (e.g., paraspinal abscess, vertebral osteomyelitis, discitis)
60
What does new back pain with neurologic deficits indicate in patients with known malignancy?
High specificity for MSCC.
## Footnote
20% of MSCC cases without known cancer present with new back pain
Commonly takes up two months to diagnose MSCC from initial presentation.
61
What is the gold standard for confirming the diagnosis of MSCC?
Magnetic resonance imaging (MRI)
## Footnote
MRI has a sensitivity of 93% and specificity of 97%
Should include Thoracic and Lumbar
Add cervical if possible
62
What is the next most informative study if MRI is unavailable or contraindicated?
CT scan of the spine
## Footnote
CT myelography can assess cord compression if vertebral metastasis is seen
It involves introduction of contrast into subarachnoid space.
63
What are the limitations of plain radiographs, PET scans, and radionuclide scans in diagnosing MSCC?
Sensitivity is limited and they provide no information about the spinal cord state
## Footnote
They cannot rule out MSCC
64
What is the initial treatment for MSCC in the emergency department?
Administration of corticosteroids
## Footnote
Followed by definitive treatment such as surgery or radiation therapy
65
What is the recommended initial dose of dexamethasone for patients with neurologic deficits due to MSCC?
10 mg intravenous bolus followed by 16 mg orally per day
## Footnote
Higher doses may be given for severe deficiencies
66
What role do corticosteroids play in the management of MSCC?
Temporize vasogenic cord edema
## Footnote
Definitive correction requires radiation therapy, surgery, or both
67
What is the benefit of combining surgical decompression with radiation therapy?
Better long-term rates of continence, ambulation, and survival
## Footnote
Recommended in the most recent guidelines
68
What is the main concern with surgical intervention for MSCC?
High complication rate
## Footnote
Mini-open approaches and postoperative stereotactic body radiation therapy show promise in reducing complications
69
What is the significance of neurointerventional radiology technologies in the context of MSCC?
They show promise for patients whose goals of care are incompatible with major surgery
## Footnote
Techniques include cement injection into spinal fractures and tumor embolization
70
What is the strongest indicator of functional outcome in MSCC treatment?
Neurologic status at initiation of treatment
## Footnote
Efforts should be made to expedite therapy to prevent further neurologic decline
71
What is the recommended timeframe for initiating definitive treatment for MSCC?
Within 24 hours whenever possible
## Footnote
No direct evidence exists for exact timing, but this is a common expert recommendation
72
What should be the disposition for patients with neurologic deficits after corticosteroid administration?
They should be hospitalized for definitive therapy
## Footnote
Asymptomatic patients may be managed as outpatients with reliable follow-up
73
What are the pericardial manifestations of malignant disease?
Pericarditis, pericardial neoplasm (usually metastatic), and pericardial effusion
## Footnote
These affect greater than 10% of cancer patients.
74
What percentage of all effusive pericardial disease in the developed world is caused by malignancy?
About 25%
## Footnote
Approximately two-thirds of malignancy-associated pericardial disease is clinically insignificant.
75
What is the primary mechanism by which neoplastic disease causes pericardial effusion?
Obstruction of lymphatic flow
## Footnote
This obstruction is often due to congestion in proximal malignant lymph nodes.
76
What are the common tumors associated with pericardial effusion?
* Lung tumors
* Breast tumors
* Hematologic tumors
* Melanoma
## Footnote
These tumors can lead to obstruction of fluid outflow and increased pericardial fluid production.
77
What is the maximum elastic potential capacity of the pericardial sac?
Greater than 1 L
## Footnote
However, it is poorly distensible in short time frames.
78
What is cardiac tamponade?
A lifethreatening condition where intrapericardial pressures rise to match or surpass those of the heart chambers, reducing cardiac output
## Footnote
This can lead to shock.
79
What are the classic presenting symptoms of pericardial disease?
* Dyspnea 91%
* Chest pain 47%
* Cough 65%
* Weakness
* Fatigue
Othopnea
## Footnote
Large effusions may cause mass effect on nearby structures.
80
What is pulsus paradoxus?
A 10 mm Hg systolic blood pressure gradient between inspiration and expiration
## Footnote
It is the most sensitive sign of pericardial disease.
81
What is Beck triad?
* Hypotension
* Elevated JVP
* Muffled heart sounds
## Footnote
This is seen in less than half of cases of cardiac tamponade.
82
What should be included in the evaluation for suspected malignant pericardial effusion?
* Chest radiography
* Electrocardiogram (ECG)
* Transthoracic echo (TTE)
## Footnote
CXR may be first sign , shows cardiomegaly, globular (“water-bottle”) heart shadow
83
What are the electrocardiographic manifestations of malignant pericardial effusion?
* Nonspecific ST or T changes 93%
* Low amplitude QRS voltage 88%
* Sinus tachycardia 56%
* Electrical alternans (seen in 10% of cases)- poor prognostic sign
84
What is the management for malignant pericardial effusion with cardiac tamponade?
Immediate drainage under real-time ultrasonographic guidance
## Footnote
This is considered a medical emergency.
85
What is the preferred approach for drainage of pericardial effusion?
Ultrasound-guided drainage by the intercostal approach
## Footnote
This method results in fewer complications and higher success rates.
86
What are temporizing measures for malignant pericardial effusion without tamponade?
* Inotropes (e.g., epinephrine, dobutamine)
* Intravenous fluids
## Footnote
These have not demonstrated reproducible benefit in humans.
87
What should be done for effusions without tamponade?
Nonemergent management and fluid sampling for cytology and tumor marker analysis
## Footnote
This helps confirm the etiology of the effusion.
88
What is a long-term management strategy for malignant effusions?
* Percutaneous drain
* Surgical window
* Percutaneous balloon pericardiotomy
## Footnote
These strategies should be considered due to the tendency for malignant effusions to recur.
89
Non malignant causes of pericardial effusion
Radiation, medications, hypothyroidism, infection
(TB,HIV), ESRD, autoimmune disorders (RA, SLE)
90
What are the physical exam findings for malignant pericardial effusion?
Physical Examination
* Majority will relatively preserve BP
* Pulsus paradoxus - sensitivity 82%
* Tachycardia (74%), JVD (68%), hepatomegaly (63%), distant heart
sounds (58%), hypotension (53%), friction rub (16%)
91
Classify pericardial effusion according to volumes
92
What hormones are primarily responsible for regulating serum calcium levels?
Parathyroid hormone (PTH) and calcitriol
## Footnote
Calcitriol is the activated form of vitamin D, and calcitonin also plays a role by decreasing serum calcium levels.
93
What is the most common cause of malignancy-associated hypercalcemia?
Synthesis of PTH-related protein (PTHrP)
## Footnote
This accounts for about 80% of cases and is often associated with squamous cancers.
94
What are the common presenting symptoms of hypercalcemia?
Weakness, lethargy, confusion, abdominal pain, nausea, vomiting, constipation, polyuria, polydipsia, kidney injury
## Footnote
Signs of dehydration may also be present.
95
What is the recommended initial treatment for severe hypercalcemia?
Intravenous fluid administration
## Footnote
This helps restore euvolemia and enhances renal elimination of calcium.
96
What is the typical dosage and administration method for bisphosphonates in treating hypercalcemia?
90 mg of pamidronate over 2 to 4 hours or 4 mg of zoledronate over 15 to 30 minutes, given intravenously
## Footnote
Oral availability of bisphosphonates may be limited.
97
What complications can arise from the use of bisphosphonates?
Renal dysfunction, jaw osteonecrosis, acute phase reaction (fever, myalgia, arthralgia, headache)
## Footnote
Acute phase reactions usually occur within 36 hours.
98
What is the role of calcitonin in the management of hypercalcemia?
Provides a quicker onset of action (12 to 24 hours) for immediate reduction of serum calcium levels
## Footnote
Its effects are short-lived due to tachyphylaxis.
99
What are some differential diagnoses to consider for malignancy-associated hypercalcemia?
Infection, direct neurologic injury, metabolic derangements (hyper- or hyponatremia, acidemia, TLS)
## Footnote
TLS stands for tumor lysis syndrome.
100
What tests are important for diagnosing malignancy-associated hypercalcemia?
Free serum calcium level, serum sodium, potassium, bicarbonate, chloride, magnesium, phosphorus, kidney function tests
## Footnote
Free or ionized calcium levels are preferred for accuracy.
101
What is the significance of primary hyperparathyroidism in cancer patients?
It occurs coincidentally with cancer and is more common than ectopic PTH production
## Footnote
Ectopic PTH production is rare and mainly documented in case reports.
102
What should be done for patients with severe hypercalcemia (>14.0 mg/dL)?
They should be admitted to a monitored bed
## Footnote
This is crucial for close monitoring and management.
103
Fill in the blank: The median survival for patients with malignancy-associated hypercalcemia is less than _______.
two months
104
True or False: Loop diuretics are recommended for all hypercalcemic patients.
False
## Footnote
Loop diuretics should only be used for volume overload, as they can worsen hypercalcemia.
105
What is denosumab used for in hypercalcemia treatment?
It inhibits the RANK ligand in bisphosphonate-resistant hypercalcemia
## Footnote
Denosumab is more expensive and used second-line.
106
What are the possible manifestations of chronic hypercalcemia?
Nephrolithiasis and nephrocalcinosis
## Footnote
These are infrequent in malignancy-associated hypercalcemia.
107
Vit D metabolism
108
Hypercalcemia treatment
109
Non malignant causes of hypercalcemia
110
What is Tumor Lysis Syndrome (TLS)?
TLS occurs when destruction of malignant cells occurs so rapidly that the body’s mechanisms for regulating the unwanted products of this destruction are overwhelmed.
## Footnote
Mortality 29% to 79%, largely on basis of patient’s underlying
functional status
111
What metabolic abnormalities are seen during TLS?
* Hyperuricemia
* Hyperkalemia
* Hyperphosphatemia
* Hypocalcemia
* AKI
112
What can acute kidney injury in TLS be caused by?
* Crystal deposits of uric acid
* Crystal-independent mechanisms of damage by uric acid
113
Which types of tumors are most likely to cause TLS?
* NHL especially Burkitt lymphoma
* Acute lymphoblastic leukemia (ALL)
* Chronic leukemia with recent chemotherapy
114
Which patient factors can predispose someone to TLS?
* Preexisting renal failure
* Hypovolemia
* Hyperuricemia
115
What are some symptoms of TLS?
* Nausea
* Vomiting
* Lethargy
* Confusion
* Edema
* Seizure
* Myalgias
* Tetany
116
What are potential cardiac effects of TLS?
* Dysrhythmias
* Cardiac arrest
117
What should be administered to patients with septic symptoms in TLS?
Empiric antibiotics
118
What diagnostic tests should be performed for TLS?
* Serum potassium
* Serum phosphate
* Ionized calcium
* Urea nitrogen
* Creatinine
* Uric acid
* Lactate dehydrogenase (LDH)
119
Fill in the blank: Measurement of __________ should be performed for patients presenting with acute kidney injury in TLS.
fractional excretion of sodium (FENa)
120
What is the initial therapy for TLS?
Intravenous fluids to promote renal clearance of unwanted metabolites
121
What volume of fluids is suggested for TLS management?
3 L/m2/day, or as high as 5 to 6 L daily
122
What is no longer supported in the management of TLS due to potential complications?
Alkalinization of the urine
123
What causes hypocalcemia in TLS?
Free calcium precipitating with excess phosphate to form calcium phosphate
124
How can hyperkalemia be managed in TLS?
* Intravenous calcium
* Administration of insulin
* Bicarbonate
* Beta-agonists
* Potassium binders
125
What pharmacological treatments can be used for hyperuricemia in TLS?
* Allopurinol
* Febuxostat
* Rasburicase
126
What is the mechanism of action of allopurinol?
Competitively inhibits enzymatic conversion of xanthine to uric acid
127
What is the main concern with using rasburicase?
It can trigger hemolytic crisis in patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency
128
What does the Cairo-Bishop definition of TLS classify?
Divides patients into laboratory TLS (LTLS) and clinical TLS (CTLS)
129
What is indicated for patients with CTLS consisting of dysrhythmia or seizure?
Admission to an ICU
130
What should be done for patients with laboratory TLS only?
Admission to a monitored bed for observation and treatment
131
Cairo-Bishop definition
132
Risk factors for Tumor Lysis Syndrome
** Tumor- related factors**
- high cell proliferation rate
- large tumor burden (bulky > 10cm, LDH> 1500 IU/L)
- WBC count ≥ 50
- extensive bone marrow involvement
- tumor infiltration of kidney
- high tumor sensitivity to chemotherapeutic agents
** Host risk factors **
- low urinary output
- preexisting hyperuricemia
- chronic kidney disease
- dehydration
- acidic urine
133
ECG changes seen in TLS
Electrocardiographic changes may include QT interval prolongation due to hypocalcemia
and P-wave flattening, PR and QRS interval prolongation, and T-wave
peaking due to hyperkalemia
134
Treatment of Metabolic abnormalities
135
What is leukostasis?
A sufficiently high WBC count causing vascular congestion, leading to organ dysfunction, typically in the lungs or CNS.
136
What are the two mechanisms believed to drive leukostasis?
1. Blast cells are larger and less deformable than normal WBCs, increasing blood viscosity.
2. Intrinsic features of leukemic cells like cytokine-induced activation of endothelial adhesion.
137
At what WBC count may patients with acute myeloid leukemia (AML) develop leukostasis?
Less than 100,000 cells/μL.
## Footnote
CLL patients may tolerate WBC counts greater than 500,000
138
What are the clinical features of leukostasis?
**Pulmonary leukostasis**
Dyspnea, tachypnea, hypoxemia, crackles or rhonchi on auscultation, bilateral opacities on imaging.
**CNS leukostasis**
Confusion, audio or visual abnormalities, headache, ataxia, coma, and possible intracranial hemorrhage
**Others**
Retinal hemorrhage, myocardial infarction, acute limb ischemia, priapism, renal vein thrombosis, renal infarction.
139
What is the gold standard diagnostic test for leukostasis?
Presence of leukocyte-clogged blood vessels on tissue pathology.
140
What is the primary goal of ED management for leukostasis?
Reduction of blood viscosity.
## Footnote
Avoid RBC transfusion in asymptomatic patients with hyperleukocytosis
141
What is leukapheresis?
A process that involves continuous removal of fractions of a patient’s blood, selective extraction of leukocytes, and return of the remaining product.
## Footnote
Leukapheresis can reduce leukocyte count by 20 to 50 % in only a few hours
142
What is Hydroxyurea used for in leukostasis management?
To pharmacologically reduce leukocyte burden over 24 to 48 hours.
## Footnote
Inhibits deoxyribonucleotide synthesis
143
What should be monitored in patients undergoing chemotherapy induction for leukostasis?
Signs of tumor lysis syndrome (TLS).
144
What is required for patients with leukostasis?
Hospitalization for monitoring, hydration, and leukocyte-reducing therapy.
145
When should asymptomatic patients with leukocytosis be hospitalized?
If they have a blast count greater than 20,000 cells/μL, have a tumor type of AML, or have a new leukemia of unknown type.
146
True or False: Normal imaging findings exclude leukostasis.
False.
147
What is the normal blood pressure range in the superior vena cava?
≤2 to 8 mm Hg.
## Footnote
It can reach upto 20 to 40 mm Hg when SVC flow is compromised.
148
What percentage of SVC syndrome cases is caused by malignancy?
More than 60%.
149
Which types of cancer are responsible for over 90% of malignancy-induced SVC syndrome cases?
* Lung cancer
* Lymphoma.
150
What is a common cause of SVC syndrome related to thrombosis?
Intraluminal mass.
151
What symptoms do patients with SVC syndrome typically present with?
* Neck swelling 82%
* Upper extremity edema- 62%
* Chest edema/dilated chest veins 38%
* Face erythema
* Dyspnea at rest 53%
* Dysphagia
* Chest pain
* Cough 50%
* Headache, confusion, leathargy as CNS venous drianage becomes compromised)
152
What physical examination findings indicate elevated venous return pressures in SVC syndrome?
* Jugular venous distention (JVD)
* Edema
* Flushing
* Cyanosis of the face, arms, and upper trunk.
153
What complications can arise from distention of the SVC?
* Vocal cord paralysis
* Blurred vision
* Horner syndrome.
154
What imaging modality is most commonly employed for diagnosing SVC syndrome?
Contrast-enhanced CT.
155
What should be obtained prior to treatment initiation in confirmed cases of SVC syndrome?
A tissue diagnosis of the offending mass.
156
What conservative management strategies are recommended in the ED for SVC syndrome?
* Elevating the head of bed
* Administration of supplemental oxygen.
157
What treatment should be initiated for patients with SVC syndrome due to obstructing thrombus?
Anticoagulation with or without thrombolytics.
158
True or False: Diuretics and steroids have proven benefits in the treatment of SVC syndrome.
False.
159
What is the primary goal in managing SVC syndrome in the ED?
Achieving basic medical stabilization.
160
What procedure may be employed for rapid reduction of SVC pressures in emergent cases?
Endovascular stenting.
161
What are some non-malignant causes of SVC syndrome?
* Histoplasmosis
* Tuberculosis
* Syphilis
* Actinomycosis
* Mediastinitis
* Vascular problems (e.g., aortic aneurysm)
* Trauma
* Local thromboses related to CV catheters and pacemaker wires.
162
What percentage of patients with SVC syndrome experience neck swelling?
82%.
163
What imaging technique can provide clues to the diagnosis of SVC syndrome?
Plain Radiography.
## Footnote
Abnormal in 78% cases
164
What is the preferred imaging method in the emergency setting for SVC syndrome?
Chest CT.
165
What treatments may be considered for SVC syndrome?
* Chemotherapy
* Radiation treatment
* Endovascular stent placement.
166
What is a recommended treatment for large acute or subacute thrombosis in SVC syndrome?
Thrombolytic therapy directly into the thrombus via catheters.
