So, here is the situation, you’re in the trauma or neuro ICU and you’re getting a patient with a head bleed or head trauma. The neurosurgeon wants to place a device to monitor or relieve the elevated intracranial pressure (ICP). What can the bedside nurse expect to need for the surgeon, patient, etc.? Once the drain is placed how do we troubleshoot the device? Well, you’ve come to the perfect place!
Caution: These are general tips and knowledge to help you feel more comfortable and properly educated for this type of situation/patient! Each facility and clinician have various policies/practices.
CONTRAINDICATIONS: Just like any other invasive procedure, prior to drilling into a patient’s head, be sure that the doctors have assessed coagulopathic state, presence of brain abscess, or scalp infection.
Generally speaking, there are two devices that could be implanted into the patient: a bolt or a drain. A patient can have just one of the two, or both. A bolt is for monitoring ICPs specifically whereas a drain can also be used to remove fluid in a therapeutic manner. There are pros and cons for each and which is chosen depends on patient-related factors.. These devices can be placed in the OR but more commonly placed at the bedside.
BOLT: A bolt is a catheter with a strain-gauge (measures a change in force) tip that is usually inserted into the parenchyma. This allows for continuous measurements of ICPs. These bolts can also be placed in the subdural and subarachnoid space. As mentioned before, it is patient/situation-dependent as well as physician preference! So why a bolt over a drain one might ask? It is less invasive, easy to install, and has much less risk of infection than an EVD. However, once inside the patient’s brain, the catheter cannot be recalibrated, if the tip of the transducer becomes kinked or occluded it can cause inaccurate measurements.
EVD: External ventricular drain that is usually placed in the lateral or third ventricles to drain CSF, blood, mitigate intracranial hypertension, and/or instill meds. With this device, you lose the accuracy of the ICP if the drain is set to drain continuously (stay open). Be aware that if the device is set to drain continuously there is an increased risk of infection and hemorrhage. The drain has to be re-zeroed with any change in the patient head of bed or transport.
The picture to the right shows the actual drain that is calibrated, zeroed, and where the CSF fluid drains into and can be monitored at all times. It is extremely important that this drain does not be moved or accidentally dislodged from the patient. The drain itself will be sutured on the patient, but the external device is something the bedside nurse needs to be aware of at all times. Please always clear if the drain should be set to mmHg or mmH2O as well. Orders will be patient and physician-driven, and can be adjusted in an acute situation just as other external devices on patients
Symptoms to be aware of that could indicate adverse events of drain and need to notify the LIP or team are as follows: infection, new-onset headache, decreased CPP, nausea, change in mental status (From baseline), and lethargy. Strong indications for infection are erythema and tenderness at the insertion site with weak to low indications being fever without other known sources.
- Remove all hair from insertion site prior to insertion to decrease the risk of infection
- Even tape will do around the head of the bed to help reduce exposure and can be done without being in the way of the Neurosurgeon
- Keep HOB 30 degrees or higher in order to decrease ICP
- Always check your orders for correct measurement of drain and when to notify NeuroSurgery of elevated ICPs/decreased CPP
- CPP- Cerebral Perfusion Pressure (MAP-ICP): generally want it between 55-60 to make sure brain is being perfused
- If EVD, is it set to drain or remain clamped?
- Always use betadine, chlorhexidine is neurotoxic
- Cluster nursing care with Respiratory Therapists so the patient is minimally stimulated
- Suctioning, turning, bathing, assessments
Compliant brain: P1>P2 Acute Brain Injury: P2>P1 (poor compliance)
P1: Percussive wave- arterial pulsation
P2: Tidal wave- intracranial compliance (change in volume or pressure)
P3: Dicrotic wave- closure of the aortic valve
Being able to read the waveform on the monitor or bedside device is crucial when caring for these patients. Just like an arterial waveform or a heart rhythm, an ICP waveform is just as important when caring for the patient. If a patient has had some sort of decompression (craniotomy), the waveform may appear dampened, but otherwise should be easy to interpret. A normal ICP waveform (top left), can be indicative of adaptive capacity, or compliance. A compliant brain will have a higher P1 than P2. Any sort of acute brain injury will be seen in the waveform as P2 being higher than P1. The level of P1 is indicative of blood pressure. If there is swelling or extra fluid around the brain, an abnormal waveform may be seen on the monitor. A tombstone waveform has the same meaning as a tombstone rhythm and usually indicates trouble ahead. Always keep an eye on your waveform and report any changes ASAP!
- Remove all hair from insertion area to reduce risk of contamination/infection
- Keep HOB 30 degrees or higher (review orders)
- Keep suctioning and stimulation to a minimum to control ICPs
- Clamp before turning or moving pt if set to drain
- If any new signs or symptoms occur notify the team
- Chau, C., Craven, C. L., Rubiano, A. M., Adams, H., Tülü, S., Czosnyka, M., Servadei, F., Ercole, A., Hutchinson, P. J., & Kolias, A. G. (2019). The Evolution of the Role of External Ventricular Drainage in Traumatic Brain Injury. Journal of clinical medicine, 8(9), 1422. https://doi.org/10.3390/jcm8091422
- Dey, M., Jaffe, J., Stadnik, A., & Awad, I. A. (2012). External ventricular drainage for intraventricular hemorrhage. Current neurology and neuroscience reports, 12(1), 24–33. https://doi.org/10.1007/s11910-011-0231-x
- Evensen, K. B., & Eide, P. K. (2020). Measuring intracranial pressure by invasive, less invasive or non-invasive means: limitations and avenues for improvement. Fluids and barriers of the CNS, 17(1), 34. https://doi.org/10.1186/s12987-020-00195-3
- Munakomi S, M Das J. Ventriculostomy. [Updated 2021 May 8]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2021 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK545317/