Episode #222 Best Practices for External Ventricular Drain Management – Part 3 of 3

Hello and welcome back to the Anesthesia Patient Safety Podcast. My name is Alli Bechtel, and I am your host. Thank you for joining us for another show. We are returning to the APSF Resources today and the External Ventricular Drain Safety Campaign. Question, what type of EVD is recommended to reduce the risk of EVD-associated ventriculitis? Answer, an anti-microbial EVD. Check out the EVD educational document for a picture of this catheter device.

Before we dive into the episode today, we’d like to recognize Nihon Kohden, a major corporate supporter of APSF. Nihon Kohden has generously provided unrestricted support to further our vision that “no one shall be harmed by anesthesia care”. Thank you, Nihon Kohden – we wouldn’t be able to do all that we do without you!”

Our featured topic again today is the External Ventricular Drain Safety Campaign: A Global Patient Safety Initiative which represents a collaboration between the APSF and The Society for Neuroscience in Anesthesiology and Critical Care. To follow along with us, head over to APSF.org and click on the Patient Safety Resources heading. Then, the 7^th one down is External Ventricular Drain Safety Campaign. I will include a link in the show notes as well.

We are going to dive a little bit further into the EVD Safety Campaign. Let’s start with increasing our knowledgebase. To follow along with us, go ahead and click on the EVD Educational Document. There are high-quality labeled pictures to help highlight how to use these devices correctly and safely. Last week, we talked about the indications and complications. Today, let’s start with device set up. Here are the recommendations.

• EVD systems should be set up by personnel familiar with the devices who have demonstrated appropriate clinical competency
• Devices should be set up observing standards of sterile techniques
• Only flush-less transducer systems are used
• The EVD system is primed with sterile, preservative free saline
• Setting should be expressed in cm H20
• And Leveling of EVD should always be made at the external auditory meatus (EAM)

Next up, how do you level an EVD?

• Connect ventricular or lumbar catheter with sterile technique
• Attach pressure cable to flush-less transducer
• Turn stopcock off to patient by turning it to “3 o’clock” position
• Open system to air by removing the red cap
• Press “zero” on monitor
• When monitor indicates “0”, return stopcock upright
• Replace injection cap

Caution ahead: Make sure that you do not connect the EVD or lumbar drain to a high-pressure system such as a pressure bag that you would use for an arterial line or central line.

For patient preparation prior to EVD placement, here are the steps that you want to take:

• Follow ASRA guidelines for lumbar drain placement & the Neurocritical Care Society guidelines for EVD for prompt coagulopathy screening and reversal prior to EVD or LD placement and maintenance
• Administer antibiotics only prior to placement of EVD or LD, and follow institutional antibiograms in selecting antibiotics
• Whenever possible use antimicrobial-impregnated EVDs
• And make sure that you practice strict aseptic technique based on national and institutional guidelines

Here are several preoperative considerations to keep in mind as well. These are important details to include as part of a complete pre-operative handoff between the intensive care team and the anesthesia team.

• Focused history and neurological examination
• CSF color and consistency. Is it hemorrhagic, xanthochromic, or tea-colored
• Hourly CSF output with a maximum of about 20 ml/hr.
• Review of the ICP values, ICP waveform analysis, ICP trends, autoregulation indices, CPP and other multimodal monitoring data as appropriate
• Clinical and radiological evidence of clamping trial tolerance

We mentioned ICP waveform. This can be monitored with an EVD and it is important to understand what you are looking at:

• The first wave, P1, is the Percussion wave due to reflections off the choroid plexus
• The second wave, P2, is the Tidal wave which reflects brain compliance and normally, the P2 wave is 80% of the P1 wave. If you see that the P2 wave is taller than P1 wave, this means that there is reduced cerebral compliance.
• Finally, the dicrotic wave reflects aortic valve closure.

Before the patient is brought down from the ICU, here are some important considerations as part of the pre-transport screening questionnaire:

• Is EVD continuously draining in the neuro ICU or is it clamped for drainage?
• What is hourly CSF drainage?
• What is CSF output over 24 hours?
• Was an EVD clamp trial conducted in the ICU?
• What were the results of the clamping trial?
• What is the baseline ICP ( < 15 mmHg, 15-19 mmHg, or > 20 mmHg)
• What is the reason for transporting patient to the anesthesia suite ( Diagnostic vs. therapeutic procedure)

There are two options for managing the EVD during transport.

Option 1:  Travel with EVD clamped

Option 2 : Travel with EVD open and draining CSF

It is important to continue monitoring during transport.

• Continue all pre-transport monitoring and documentation which may include
  • End tidal carbon dioxide
  • Mean and systolic arterial pressures
  • Intracranial pressure, brain tissue oxygenation
  • Cerebral perfusion pressure
• Use a dedicated intravenous pole to mount EVD and LD
• Transport personnel be prepared to treat intracranial hypertension during intrahospital transport
• Individualize decision to transport with EVD open vs. closed to CSF drainage

Phew, we made it to the operating room. We need to continue our vigilant monitoring to keep our patients with EVD safe.

• Document the following in the anesthetic record at least every hour or more frequently as the situation demands
  • Pressure = ICP/CPP or intraspinal pressure (ISP)/ spinal cord perfusion pressure (SCPP)
  • Amount of CSF drainage (expressed in ml)
  • Color of CSF and any change in color of CSF observed during the procedure
  • Drain height relative to the reference level
  • EVD / LD status as set by the stopcocks in the device (i.e. open, clamped)
• Incorporate all information pertinent to EVD and LD into a standardized intraoperative handoff between anesthesia providers

Anesthesia professionals are good at troubleshooting in many different situations. Here are several considerations for EVD troubleshooting.

• Promptly recognize any accidental intrathecal injection, but lavage of the intrathecal space after intrathecal injection is not recommended
• Routine flushing of the EVD should not be performed
• EVD tubing that is accidentally disconnected should be clamped immediately
• If EVD system is contaminated by disconnection, all distal parts should be replaced with new sterile tubing

You must remain vigilant for any of these critical changes:

• sudden change in color of CSF
• sudden drainage of CSF of 15-20mls
• the EVD or LD suddenly stops draining
• Dampening of the ICP waveform

This is time to alert the neurosurgeon immediately and if you are being supervised to inform your attending.

The Educational Document has a Perioperative Checklist at the end. It includes all of the information that we just went through in a tidy checklist. This is a great resource to print out and have on hand any time that you are providing care for a patient with an EVD or LD.

Now, we are going to look a little closer at the EVD policy and procedure template, which is an evidence-based document that you can use to implement best practices at your institution. Go ahead and click on the PDF link from the Resource Page and scroll down until you get to EVD Maintenance. This section is really important for anaesthesia professionals who are providing anaesthesia care for patients with an EVD to understand how the EVD is maintained in the ICU prior to transport to theatre and afterwards.

Here we go:

1. Monitoring for signs and symptoms associated with changing ICP which may include decreased level of consciousness, nausea, vomiting, headache, lethargy, or agitation. Neurological assessments should be performed and documented hourly, or more frequently as the clinical situation warrants
2. Hourly assessment includes CSF drainage, color, and clarity
3. Measure ICP every hour. Notify the physician immediately if ICP exceeds established parameters. If no parameter is specified, notify the physician if ICP is >20 mmHg. To obtain accurate ICP monitoring, the stopcock should be at the 12 o’clock position.
4. Keep HOB elevated 30°unless otherwise ordered by Physician/NP/PA.
5. Check the patient’s position to ensure the transducer is at the ordered reference level. If the patient is very active and moving around in bed, it is imperative to frequently assess that the drain is levelled appropriately to prevent over- or under-drainage.
6. Verify neurocritical care primary team orders for drain height every shift and drainage parameters if indicated (mL/hour).
7. Verify the correct placement of the drainage chamber every 1- 2 hours and with every position change. Maintain cylinder in an upright position at all times.
8. Ensure the system is appropriately clamped or open depending on patient situation and physician order.
9. Assessment of the drainage system should be done a minimum of every 4 hours, which includes inspecting the EVD from the insertion site along with the entire drainage system, checking for cracks in the system or fluid leaking from the insertion site.
10. Check EVD for patency as needed by lowering the entire system for a brief moment to assess drip-rate into the graduated burette.
11. Waveform assessment should be ongoing with special attention noted to P1, P2, and P3 components. Be aware of changes in waveform and troubleshoot when warranted.
12. Document ICP waveform assessment once a shift and as waveform changes occur. Perform waveform analysis upon initial assessment of patient and system, establishing a baseline to use for comparison throughout the shift.
13. Observe ICP in relation to other hemodynamic parameters such as MAP, which will give an indicator of CPP.
14. If the ventricular drain is used for continuous drainage, clamp momentarily for changes in position, and suction.
15. After the patient activity that required clamping is completed, verify that the clamp is open at the pre-ordered level and HOB is returned to the previous position.
16. The transducer is re-zeroed after a shift and at least every 12 hours, as a troubleshooting technique, or when interface with the monitor has been interrupted.
17. Use of mechanical VTE prophylaxis (sequential compression device or intermittent pneumatic compression) in all patients with contraindications to pharmacological prophylaxis (UFH or LMWH) and without contraindications to mechanical devices.
18. In patients with additional risk factors for VTE (including, but not limited to concurrent malignancy, trauma, spinal cord injury, critical illness, and immobilization), suggest pharmacological prophylaxis after an intracranial hemorrhage has been ruled out or is stable.
19. Avoid routinely changing catheter sites.

As you can see, a lot of work goes into keeping patients with an EVD safe in the ICU and it is imperative that anesthesia professionals remain vigilant in the operating room to keep patients with EVDs safe as well.

Another important way to keep patients safe is by gather more information and we have resources so that you can collect data on quality and safety regarding EVDs. SNACC has created a list of electronic clinical quality metrics that you can start implementing at your hospital. These metrics are based on the evidence-based recommendations. Check it out on the EVD Safety Campaign page or in the show notes.

The EVD Safety Campaign provides the foundation for an education session that you can go through on your own or invite a few colleagues and review these materials with your perioperative team or anesthesia department. With this APSF resource, all you need to do is bring the coffee.

If you have any questions or comments from today’s show, please email us at [email protected]. Please keep in mind that the information in this show is provided for informational purposes only and does not constitute medical or legal advice. We hope that you will visit APSF.org for detailed information and check out the show notes for links to all the topics we discussed today.

The EVD Safety Campaign provides the foundation for an education session that you can go through on your own or invite a few colleagues and review these materials with your perioperative team or anesthesia department. With this APSF resource, all you need to do is bring the coffee.

Until next time, stay vigilant so that no one shall be harmed by anesthesia care.

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