Management Protocol for Ommaya (Intraventricular) Reservoir
The management of an Ommaya reservoir requires strict adherence to infection prevention protocols, including minimal manipulation of the device, standardized sterile access techniques, and use by only highly qualified personnel to minimize infection risk and maximize device longevity. 1
Pre-Insertion Considerations
- Preprocedural antimicrobials: Administer cefazolin before insertion to reduce surgical site and central nervous system infections 1, 2
- Skin preparation: Perform perioperative chlorhexidine shampoo and hair clipping, avoiding skin abrasions 1
- Placement technique: Position the reservoir under a skin flap at a safe distance from the incision site 1
- Consider antibiotic-impregnated catheters: Minocycline/rifampin-impregnated or silver-coated catheters significantly reduce infection rates (risk ratio 0.31) 1, 2
Insertion Technique
- Use image guidance (fluoroscopy, endoscopy, ultrasound, or stereotaxy) to ensure accurate catheter placement in the lateral ventricle 3, 4
- Preassemble the reservoir and catheter to minimize risk of clogging during placement 3
- Recess the reservoir for better cosmetic results 3
- Confirm catheter position with intraoperative imaging when possible 4
- Obtain post-insertion CT scan before initiating intraventricular therapy 4
Accessing the Reservoir
- Personnel restrictions: Allow only specially trained personnel to access the device 5
- Strict aseptic technique: Implement standardized protocols for reservoir access 1, 5
- Hand washing using surgical theater-standard scrubs
- Wearing mask and gloves
- Thorough cleaning of access ports
- Minimize manipulation: Reduce frequency of CSF sampling to only when clinically necessary 1
- Consider chlorhexidine-impregnated dressings at the catheter exit site to reduce infection risk 1
Monitoring and Maintenance
- Monitor for signs of infection:
- Local skin/soft tissue inflammation
- Meningitis/ventriculitis symptoms (fever, headache, neck stiffness)
- Consider CSF analysis with cultures when infection is suspected 1
- Watch for complications:
- Catheter malposition or disconnection
- Hemorrhage
- Wound dehiscence
- Catheter tract leukoencephalopathy/edema 1
- Document all reservoir parameters, including CSF appearance and neurological status 2
Infection Prevention Bundle
- Implement a comprehensive infection control protocol including:
- Standardized hand washing technique
- Surgical theater-standard preparations
- Chlorhexidine-impregnated dressings
- Minimal device manipulation 1
Advantages of Ommaya Reservoirs
- Reduces patient anxiety and discomfort compared to serial lumbar punctures 1
- Avoids complications inherent to lumbar punctures (post-dural puncture headaches, low back pain, radiculopathy) 1
- Eliminates need for anticoagulation holds 1
- Allows more frequent and reliable monitoring of CSF 1
- Improves drug dissemination through the intrathecal space due to pulsatile CSF flow 1
- Associated with improved survival compared to lumbar drug delivery 1
Complication Rates and Prevention
Modern complication rates are substantially lower than historical estimates:
- Contemporary infection rates: 0.9-3.8% (vs. historical 15%) 1
- Perioperative hemorrhage: 0.9-6.4% 1
- Malfunction: 0.9-2.8% 1
- Wound dehiscence: 1.8% 1
- Catheter tract issues: 1.8% 1
These risks are minimized with experienced surgeons and strict sterile access techniques 1, 5.
Special Considerations
- Assess for elevated intracranial pressure before placement, as some patients may require ventriculoperitoneal shunting instead 4
- Monitor for treatment-related imaging abnormalities, including leukoencephalopathy 4, 6
- Verify catheter position before initiating intraventricular chemotherapy 4
By following this protocol, Ommaya reservoirs can be safely managed with minimal complications, as demonstrated by long-term studies showing infection rates as low as 1% over thousands of drug administrations 5.