Tumor lysis syndrome

Tumor lysis syndrome (TLS)

is a potentially life-threatening complication that can occur in patients with cancer, most commonly seen in those with rapidly growing or highly sensitive tumors following initiation of cancer treatment. 

TLS occurs when large amounts of cancer cells are destroyed rapidly, leading to the release of their contents into the bloodstream. 

 TLS is considered a medical emergency, and immediate medical attention should be sought if symptoms develop. Early recognition and intervention can improve outcomes and prevent life-threatening complications.

 Pathophysiology and symptoms

The breakdown of tumor cells releases intracellular contents, such as potassium, phosphorus, and nucleic acids, into the bloodstream. This sudden release overwhelms the body's ability to eliminate these substances, leading to electrolyte imbalances. Electrolytes imbalance in TLS

hyperkalemia (elevated levels of potassium), 

hyperphosphatemia (elevated levels of phosphorus), and

  hypocalcemia (reduced levels of calcium). 

TLS can also cause acute kidney injury due to the deposition of uric acid crystals in the kidneys. 

 Symptoms

 The symptoms of TLS can vary but may include weakness, fatigue, nausea, vomiting, decreased urine output, rapid heartbeat, muscle cramps, and seizures.

It is crucial to identify and manage TLS promptly to prevent serious complications, such as kidney failure, cardiac arrhythmias, and even death. 

 Prevention and treatment 

 Prevention and management of TLS involve 

careful monitoring of electrolyte levels before and during cancer treatment,

 aggressive hydrationhyperhydration 

the administration of medications to control the levels of uric acid and other electrolytes, and potentially dialysis in severe cases.

 In some situations, prophylactic measures may be taken to prevent TLS in high-risk patients.

 Aggressive hyperhydration

by means of intravenous fluids (2500 to 3000 ml per square meter per day in the patients at highest risk). 

Hydration is the preferred method of increasing urine output, but diuretics may also be to facilitate the excretion of uric acid 

 Types of IV fluids used in hyperhydration 

 1. Normal saline (0.9% saline): This is the most commonly used IV fluid for hyperhydration in tumor lysis syndrome. 

It is isotonic and helps to restore fluid balance in the body.

 2. Dextrose 5% in water (D5W): This is a hypotonic IV fluid that is used to provide fluids and calories to the body. It is often used in combination with normal saline.

 3. Ringer's lactate: This IV fluid is used to correct electrolyte imbalances in the body. It contains lactate, which helps to buffer the pH of the blood. 

 4. Hypertonic saline (3% saline): This IV fluid is used in severe cases of tumor lysis syndrome where there is a risk of cerebral edema. It helps to reduce brain swelling and lower intracranial pressure. 

 5. Colloids: These are IV fluids that contain large molecules such as albumin or starch. They are used to increase plasma volume and minimize the risk of hypotension in patients with tumor lysis syndrome. 

6. Mannitol: This is a diuretic IV fluid that is used to reduce intracranial pressure in patients with cerebral edema. It works by drawing water out of brain cells and into the bloodstream. 

 Management of hyperkalemia

 Hyperkalemia is a potentially life-threatening condition characterized by high levels of potassium in the blood. 

 1.Frequent monitoring of potassium level every 4 to 6 hrs and Restricting potassium intake: Limiting potassium from the diet or from medications is an initial step. Foods and drinks high in potassium such as bananas, oranges, and sports drinks must be avoid Hyperkalemia is a potentially life-threatening condition characterized by high levels of potassium in the blood. 

 2. Medications: Medications may be given to bind or move potassium into cells and out of the bloodstream. These include sodium polystyrene sulfonate, beta agonist nebs,calcium gluconate, insulin, and glucose. The choice of medication is dependent upon the severity of the hyperkalemia.