1. Oncology Emergencies in PICU
Norah Khathlan MD
Pediatric Intensivist
Director PICU
November 2006

2. Oncology Emergencies in the PICU
MEDIASTINAL MASSES
SVC Syndrome
HYPERLEUKOCYTOSIS
TUMOR LYSIS SYNDROME
SEPTIC SHOCK
ARDS
SPINAL Cord Compression.
CNS Events

3. Oncology Emergencies in the PICU
1- TUMOR LYSIS SYNDROME
Metabolic abnormalities occurring as a result of tumor cell death:
Spontaneously
Chemotherapy
Starting chemotherapy on rapidly growing-chemo-sensitive tumors  release of intracellular contents into circulation.

4. TUMOR LYSIS SYNDROME Hyperkalemia. Hyperphospatemia. 2ry Hypocalcemia.
Hyperuricemia.
Uremia.
High creatinine.
Oliguria.

5. TUMOR LYSIS SYNDROME Incidence:
70% of hematological malignancies  laboratory criteria of TLS.
3% with clinical TLS.
Associated with hematological malignancies:
ALL
AML
Lymphomas
Solid tumors

6. TUMOR LYSIS SYNDROME Maybe precipitated by : Risk factors:
Chemotherapy
steroids
Radiotherapy.
Hormonal agents.
Risk factors:
Tumor type
Dehydration
Preexisting renal insufficiency
Nephrotoxic medications
High LDH in TLS is indicative of likely progression to ARF

7. TUMOR LYSIS SYNDROME MANAGEMENT: Identify at risk patients.
Admit to PICU.
Consult Nephrology service
Establish good venous access prefer. CVC.
Frequent lab monitoring of:
- Na+ - Ca++
- K+ - Uric acid
- Cl- - Creatinine
- PO Urea
- Bicarbonate - LDH

8. TUMOR LYSIS SYNDROME MANAGEMENT: cont. Urine analysis and pH
HYDRATION THERAPY:
2-3 L/m2/day OR 1 1/2 to 2 x maintenance
Start hrs prior to chemotherapy.
Isotonic NS or Hypotonic saline if Urine Na <150 meq/L
Alkalinization of the urine to pH = controversial !
Diuretics controversial !
Mannitol if suboptimal diuresis
Avoid P.O. or exogenous K+, potassium sparing diuretics, ACE inhibitors and uric acid tubular re-absorption blockers.

9. TUMOR LYSIS SYNDROME Specific management: Hyperkalemia:
Ca gluoconate
Na Bicarbonate
Insulin & Glucose
Salbutamol
K binding resins
DIALYSIS or CRRT “CVVHD” for K>5

10. TUMOR LYSIS SYNDROME Hyperphosphatemia & 2ry Hypocalcemia:
Phosphate binders eg. Aluminum antacids.
Avoid unnecessary Ca supplements.
PO4 > 4 is an indication for dialysis.
Consider CRRT.

11. TUMOR LYSIS SYNDROME Hyperuricemia:
Urine Alkalinization maximizes Uric acid solubility
Urine pH > 6 and < 7.5
Avoid urine pH more than 7.5 “may lead to massive phosphate crystalluria and phosphate precipitates”.

12. Xanthine Hypoxanthine
Tumor Lysis Syndrome
Allopurinol:
Xanthine oxidase inhibitor:
Xanthine Hypoxanthine
Xanthine oxidae -
-ve
allopurinol
Uric Acid
Blocks production of new Uric acid
Increased levels of uric acid precursors; Xanthine nephrotoxic
Impairs chemotherapy metabolism

13. TUMOR LYSIS SYNDROME Hyperuricemia: cont.
Non recombinant urate oxidase (Uricozyme)
urate oxidase
Uric Acid  Allantoins “highly soluble in urine”
Recombinant Urate Oxidase (Rasburicase)
Effective: Single dose decreases uric acid from 15 to 0.4 mg/dl in 24 hrs
Costs
C.I. in G6PD deficiency
====================

14. Oncologic Emergencies in PICU
2- Hyperleukocytosis
WBC counts > 100,000/ul in 5-20% children ALL
Clinically significant if > 300,000 in ALL
Marked elevation of blood viscosity:
erythrocyte + Leukocyte volumes and deformability of cells.
Normal = relative to water
Clinical manifestation if > 4
Mainly affects CNS & Lungs
Leukocyte aggregation.
Small vessel obstruction.
Decreased perfusion of microcirculation.
Vascular stasis, Leukostasis.
Risk of Intra Cranial Hmg and /or IVH & SAH
Role of Cytokines !!

15. Hyperleukocytosis Management: Lack of controlled trials.
Avoid Packed RBCs transfusion
Avoid diuretics.
Maintain platelets > 20,000
Correct coagulopathy
Hydration,? Alkalinization and allopurinol:
Used in ALL & WBCs > 100,000  80% reduction in 36hrs no complications.
Exchange transfusion & Leukapheresis;
Needs anticoagulants and vascular access.
Rebound WBC count.
No effect on pulmonary status, CNS outcome or mortality.
NO ROLE FOR STEROIDS NOR emergency CRANIAL RADIATION

16. Oncology Emergencies in the PICU
3- Anterior Mediastinal Mass
Airway & circulatory compromise posed by mediastinal masses provide some of the great challenges in the PICU and in OR
This is a genuine emergency!!

17. Anterior Mediastinal Mass
Lymphomas
Teratomas
Middle:
Lymphoma
Posterior:
neuroblastoma

19. Anterior Mediastinal Mass
Signs & Symptoms:
Respiratory symptoms predominate: > 50% narrowing
Air hunger
Dyspnea
Wheezing
Anxiety
Position of comfort.
SVC obstruction symptoms:
Facial swelling
Periorbital edema
Conjunctival suffusion
Headache & Dizziness

20. Anterior Mediastinal Mass
Evaluation:
Quick & cautious approach is a must!!!
Inappropriate delay, investigation and /or management may be catastrophic !!
CXR: PA & Lat.  wide mediastinum
CT Chest:
No sedation May lead to cardio respiratory arrest
No supine position

21. Anterior Mediastinal Mass
CBC & blood film
LDH
Β-HCG & α-fetoprotein
BMA & biopsy
Pleural fluid LOCAL Anesthetic
Pericardial fluid Only
Lymph node biopsy

22. Anterior Mediastinal Mass
If still no diagnosis: nearly 27% of cases
Empiric therapy
Steroids
Chemotherapy
Radiation OR
More Invasive testing

23. Anterior Mediastinal Mass
Accurate diagnosis is preferable but Significant risk of induction of general anesthesia must be considered
Predictors of safe G.A.:
Echo to evaluate cardiac motility & venous return
PFT : PEF rates > 5o% predicted
Tracheal cross-sectional area > 50%
Different Protocols for different PICUs depending on the available support.

24. Anterior Mediastinal Mass
In a Study to assess risk of G.A in patients with SVC syndrome,163 children with anterior mediastinal masses were reviewed:
44 underwent G.A. prior to therapy:
Seven (16%) developed life-threatening airway compromise.
Three needed chemotherapy or radiation prior to extubation.
However all survived.
Ferrari et al; General Anesthesia prior to treatment of anterior mediastinal masses in Pediatric cancer patients, Anesthesiology 1990

25. Anterior Mediastinal Mass
Intubation should be performed:
Awake with FOB.
Spontaneously breathing.
Sitting position.
Lower extremities venous access.
Standby ECMO or CPB
If above is not feasible:
Seriously consider empiric steroids +/- chemo or radiotherapy

26. Oncology emergencies in the PICU
Coordination of care is essential for optimal care.
Communication and collaboration among the members of the health care team improves quality and efficiency of patient care.
Everyone has an important role in the team, BUT there must be a “Captain of the Ship”.

27. NOW Back to our patient