Mitomycin is a chemotherapy agent used to treat various cancers, including gastric, pancreatic, and breast carcinomas. Because of its hazardous nature and potential for severe tissue damage upon extravasation, its intravenous administration requires a meticulous, stepwise approach by qualified personnel. Healthcare facilities must have institutional guidelines in place to ensure patient safety throughout the process. The following sections detail the essential procedures for handling and administering mitomycin.
Essential Pre-Administration Safety Checks
Before a single dose of mitomycin is prepared or administered, several critical steps must be completed to ensure patient safety and readiness for treatment.
Patient Evaluation and Assessment
- Review Laboratory Results: Check recent blood counts, including white blood cell (WBC) count, platelet count, and hemoglobin levels. Mitomycin causes cumulative myelosuppression, so repeat dosages should not be given until a full hematologic recovery is observed (e.g., WBC count >4000/mm$^3$ and platelet count >100,000/mm$^3$).
- Assess Renal Function: Verify serum creatinine levels. The use of mitomycin should be avoided in patients with a serum creatinine greater than 1.7 mg/dL due to the risk of renal toxicity.
- Verify Venous Access: A functioning intravenous catheter is mandatory. A central venous access device (CVAD) is strongly recommended for administering vesicant chemotherapy to minimize the risk of extravasation. Assess the patency of the IV line by checking for blood return and flushing with saline before connecting the medication. If resistance is noted or patency is uncertain, a new, secure access site must be established.
Mitomycin Preparation and Reconstitution
Mitomycin is supplied as a sterile, dry powder that requires reconstitution and dilution according to institutional policies for hazardous medications.
- Protective Equipment: All personnel preparing the drug must wear appropriate personal protective equipment (PPE), including a gown, gloves, and eye protection, in a designated biological safety cabinet.
- Reconstitution: For a 5 mg vial, reconstitute with 10 mL of Sterile Water for Injection to achieve a concentration of 0.5 mg/mL. For other vial sizes, follow the manufacturer's specific instructions.
- Dissolution: Gently shake the vial to dissolve the powder. If dissolution is not immediate, allow it to stand at room temperature until the solution is obtained. The reconstituted solution is a blue-violet color.
- Inspection: Visually inspect the reconstituted solution for particulate matter and discoloration before further dilution.
- Dilution: The reconstituted mitomycin can be further diluted for infusion in 0.9% Sodium Chloride Injection or 5% Dextrose Injection. Common concentrations range from 0.02 to 0.04 mg/mL.
- Stability: Adhere to stability timelines for the diluted solution. For example, stability in 0.9% sodium chloride is 12 hours at room temperature, while in 5% dextrose, it is 3 hours.
Administering Mitomycin IV
Mitomycin is a vesicant, meaning it can cause severe tissue damage if it leaks into the surrounding tissue. Vigilance is key during administration.
Administration Methods
- Slow IV Push: Administer over 3 to 10 minutes via a freely running dextrose or saline infusion. This method requires careful observation throughout the entire injection.
- Short Intermittent Infusion: Administer over a 15 to 30-minute period via a freely running IV line. This is the preferred method for many institutions and should be performed via a central venous catheter.
Extravasation Prevention
- Always administer through a patent, freely flowing IV line, preferably a CVAD.
- Continuously monitor the injection site during and immediately after administration for signs of extravasation, including pain, swelling, redness, or poor blood return.
Mitomycin vs. Intravesical Administration: A Comparison
While this article focuses on intravenous administration, mitomycin is also used intravesically (directly into the bladder) for superficial bladder cancer. The administration route is determined by the type and location of the cancer being treated.
| Feature | Intravenous (IV) Administration | Intravesical Administration |
|---|---|---|
| Indication | Metastatic gastric, pancreatic, and breast cancers, among others. | Superficial bladder cancer to prevent recurrence after transurethral resection. |
| Target | Systemic circulation for treatment of distant tumors. | Local application directly to the bladder lining. |
| Procedure | Administered as a slow push or short infusion over a period of minutes. | Instilled directly into the bladder via a catheter and retained for 1-2 hours. |
| Reconstitution | Typically reconstituted with Sterile Water for Injection, then diluted with saline or dextrose. | Usually reconstituted with sterile water and administered directly, sometimes with sodium bicarbonate to raise pH. |
| Primary Risk | Extravasation, causing severe tissue necrosis. | Chemical Cystitis, causing bladder irritation and local inflammation. |
How to Manage Mitomycin Extravasation
If extravasation is suspected, immediate action is critical to minimize damage.
- Stop Infusion: Immediately stop the infusion and clamp the IV line.
- Aspiration: If possible, attempt to aspirate the extravasated drug from the catheter and surrounding tissue.
- Removal: Remove the IV needle or catheter carefully after attempting aspiration.
- Application: Apply a cold compress to the site for at least 12 hours, typically for 20 minutes, 4 times daily for the first 24-48 hours.
- Evaluation: Mark the affected area and monitor it closely for pain, swelling, and changes in skin color.
- Topical Treatment: Institutional protocols may include applying topical treatments like dimethylsulfoxide (DMSO) to the site.
- Consultation: Notify the physician immediately and consult with a specialist for further management. Extensive injuries may require surgical debridement and skin grafting.
Post-Administration Patient Education and Monitoring
After administration, it is important to educate the patient and continue monitoring for side effects.
- Monitor for Side Effects: Watch for common side effects like nausea, vomiting, and loss of appetite. Also, monitor for signs of infection (fever, chills) and unusual bleeding or bruising, which indicate myelosuppression.
- Delayed Extravasation: Patients should be educated to report any signs of redness, pain, or swelling at the injection site, as extravasation injuries from mitomycin can have a delayed onset, sometimes appearing weeks or months later.
- Renal and Pulmonary Toxicity: Long-term follow-up should include monitoring for signs of renal toxicity, such as hemolytic uremic syndrome (HUS), and pulmonary toxicity, including interstitial pneumonia.
Conclusion
Safe and effective intravenous mitomycin administration is a high-stakes procedure demanding rigorous adherence to protocol and continuous professional vigilance. The preparation process involves careful reconstitution and handling to prevent exposure, while the administration itself requires a patent IV line and careful monitoring to avoid extravasation. In the event of an extravasation, a prompt and coordinated response is critical to minimize tissue damage. Adhering to these safety measures, along with thorough patient monitoring for both immediate and delayed effects, is paramount for optimizing patient outcomes when using this potent cytotoxic agent.
For additional professional guidance on the drug, refer to official product information or specialized oncology resources, such as those found on Drugs.com.
