94 Intraventricular Catheter with External Transducer for CSF Drainage and ICP Monitoring 843

PROCEDURE Intraventricular Catheter 94 with External Transducer for Cerebrospinal Fluid Drainage and Intracranial Pressure Monitoring

Stephanie Cox PURPOSE: An intraventricular catheter with an external transducer is used to monitor intracranial pressure and, in the presence of pathology, to alleviate increased intracranial pressure by draining cerebrospinal ﬂ uid (CSF) from the ventricular system.

PREREQUISITE NURSING hemorrhage vasospasm may need higher CPPs to main- KNOWLEDGE tain adequate perfusion through vasospastic cerebral blood vessels. 7 Patients with other neurological injuries • Knowledge of neuroanatomy and physiology is needed. require individualized CPP parameters refl ective of the • Understanding is needed regarding the assembly and neuropathology and brain perfusion needs. maintenance of the intraventricular catheter with an exter- • Elevations in ICP result when one or more intracranial nal transducer and drainage system, care of the insertion components—blood, CSF, or brain tissue—increase site, and drainage techniques. without an accompanying decrease in one or two of the • Principles of aseptic technique should be understood. Of other intracranial components. This is known as the all the intracranial pressure monitoring devices, external Monro-Kellie doctrine or hypothesis.1,20 ventricular drains (EVDs) have the greatest risk of • Clinical conditions that frequently result in increased infection.1,4 intracranial pressure include traumatic brain injury, • Institutional standards may vary with regard to antiseptic ischemic stroke,36 subarachnoid hemorrhage,7 intraparen- choice—follow your institutional standard. Although the chymal hemorrhage,30 brain tumor, meningitis, and hydro- package insert for chlorhexidine warns against use before cephalus.1,27 An EVD may be indicated in the management any neuraxial procedures, a large retrospective study and of intracranial pressure in each of these conditions. 2 several anesthesiology societies recommend chlorhexi- • Fiberoptic catheters and the microsensors that are placed dine as an antiseptic.14,15,18,33 during surgery in the surgical site or through a bolt in the • The normal range for intracranial pressure (ICP) is 0 to skull are also used to monitor the ICP. They may be placed 15 mm Hg.1,26,29 This measurement refl ects the pressure in the epidural, subdural, subarachnoid, ventricular, and exerted by the intracranial contents within the skull, intraparenchymal spaces. 28,29 These catheters are sentinels including brain, blood, and cerebrospinal fl uid.26 for increased ICP but may not be designed for treatment • Cerebral perfusion pressure (CPP) is a derived mathe- of increased ICP with CSF drainage.28,29 When a ventricu- matic calculation that indirectly refl ects the adequacy of lar catheter is inserted and transduced at the level of the cerebral blood fl ow. The CPP is calculated by subtracting foramen of Monro, approximately at the level of the exter- the ICP from the mean arterial pressure (MAP); thus, nal auditory canal, it produces a value and a waveform CPP = MAP − ICP.1,28 The normal CPP range for adults is that refl ects the ICP. The EVD is considered the most approximately 60 to 100 mm Hg 22 or a mean of 80 mm accurate ICP monitor. 1,4 Hg.20,29 The optimal CPP for a given patient and clinical • CSF is formed within the lateral ventricles of the cerebral condition is not entirely known. ICP and CPP should be hemispheres by the choroid plexus. From the lateral ven- managed concomitantly and recorded. According to the tricles, fl uid drains into the foramen of Monro, the intra- Brain Trauma Foundation Guidelines, an acceptable CPP ventricular foramina, and into the third ventricle adjacent for an adult with a severe traumatic brain injury (Glasgow to the thalamus. Although most of the CSF is made in the Coma Scale [GCS] score of ≤ 8) lies between 50 and choroid plexus of the lateral ventricles, the third ventricle 70 mm Hg.4 Patients with aneurysmal subarachnoid contributes some CSF, which then passes through the

842 94 Intraventricular Catheter With External Transducer for CSF Drainage and ICP Monitoring 843

aqueduct of Sylvius into the fourth ventricle at the pons monitoring (or EEG-based consciousness/sedation moni- and medulla. The choroid plexus in the roof of the fourth toring) for burst suppression is necessary to achieve the ventricle and the brain parenchyma itself5 contribute an desired decrease in cerebral oxygen consumption and additional small amount of CSF. The fl uid then enters into electrical stimuli.12 Additional strategies include decom- the subarachnoid space, with the major portion of the fl uid pressive craniectomy and hemispherectomy.1,11,28,35 moving through the foramen of Magendie, where it is • Underdrainage of CSF may result in sustained increased dispersed around the spinal cord and through the foramen intracranial pressure and herniation. 22,25,28,29 of Luschka, where it fl ows around the brain. CSF is • Over drainage of CSF may result in headache, subdural absorbed by the arachnoid villi, also known as arachnoid hematoma, pneumocephalus, and herniation.22,25,28,29 granulations, where it drains into the venous system to be returned to the heart.3,6 EQUIPMENT • CSF is a clear colorless liquid of low specifi c gravity with no red blood cells and only 0 to 5 white blood cells • Cranial access tray with drill (WBCs). Approximately 150 mL of CSF circulates within • Ventricular catheter the CSF pathways in the brain and spinal subarachnoid • Pressure monitor tubing kit, including pressure tubing, space. CSF is secreted at the rate of 0.35 mL/min or transducer, a three-way stopcock, or a fl ushless transducer approximately 20 mL/hr.3 with stopcock • ICP waveform morphology refl ects transmission of arterial • Nonvented sterile caps and venous pressure through the CSF and brain paren- • External drainage system, including tubing, collection chyma. The normal ICP waveform has three or four peaks, chamber, and drainage bag

with P1 being of greater amplitude than P2 , and P2 of greater • Preservative-free normal saline solution amplitude than P3 . P1 is thought to reﬂ ect arterial pressure; • Pressure monitoring cable and module P2 , P 3, and P 4 (when present) have been described as origi- • Sterile syringes nating from the choroid plexus or veins (see Fig. 92-2 ).1,28 • Skin/site preparation with antiseptic solution

The amplitude of P2 may exceed P1 with increased ICP or • Sterile towels, drapes decreased intracranial compliance (see Fig. 92-3 ). • Local anesthetic (e.g., lidocaine 1% or 2% without • During ICP elevations, pathological (Lundberg) wave- epinephrine) form trends include a, b, and c waves. The a waves, also • Sutures or staples referred to as plateau waves, are associated with ICP • Sterile dressing values of 50 to 100 mm Hg and last 5 to 20 minutes. The • Tape a waves are associated with abrupt neurological deteriora- • Laboratory forms and specimen labels (for CSF tion and herniation and are the most ominous 1 (see specimens) Fig. 92-4 ). The b waves (see Fig. 92-5), with ICP values • CSF specimen tubes (for collection of CSF) of 20 to 50 mm Hg, last 30 seconds to 2 minutes and may • Caps, masks, sterile drapes, gloves, and gowns become a waves. The c waves (see Fig. 92-6) may coin- • Cautery as required by institutional standard (for bedside cide with ICPs as high as 20 mm Hg but are short lasting insertion) and without clinical signifi cance (see Fig. 92-6 ).1 • Leveling device (e.g., carpenter ’ s, laser, or line level) • Some external ventricular drainage systems may also • Intravenous (IV) pole provide simultaneous drainage and trending of the intra- Additional equipment, to have available as needed, includes cranial pressure. the following: • Management of acute brain injury is aimed at decreasing • Suction secondary brain injury from increased intracranial pressure, decreased cerebral perfusion pressure, impaired auto- PATIENT AND FAMILY EDUCATION regulation, hypotension, hypoxemia, cerebral ischemia, hypercarbia, hyperthermia, hypoglycemia, hyperglyce- • Explain the procedure to the patient/family. This proce- mia, seizures or abnormalities in cerebral blood fl ow. dure may be performed at the bedside and require the Interventions should include strict blood pressure manage- patient to be sedated, paralyzed, and intubated. Rationale: ment, decreased environmental stimuli, elevation of the Patient cooperation during cranial access is of utmost head of the bed, alignment of the head and neck in a importance. The patient and family should be aware that straight position to promote venous drainage, the avoid- the patient may need to be intubated to maintain a patent ance of constrictive devices about the neck that might airway, ensure adequate oxygenation, and maintain a impede arterial fl ow to the brain and venous drainage from normal ICP and an adequate CPP. the brain, seizure prophylaxis, glucose control, and attain- • Assess the patient and the family for understanding of ICP ing and maintaining normothermia without shivering.1,26 pressure monitoring. Rationale: Knowledge and informa- • In addition to CSF drainage, management of increased tion may lessen anxiety. ICP frequently requires the use of certain pharmacological • Explain the potential need for low environmental stimula- agents to lessen intracranial pressure, including sedation tion, especially during periods of ICP elevations (decreased and analgesia, osmotic diuretics, hypertonic saline, neu- noise, decreased tactile stimulation, and low lighting). romuscular blockade, and barbiturates. In the case of bar- Rationale: Knowledge and information may lessen biturate coma, continuous electroencephalographic (EEG) anxiety and present expectations of potential events. 844 Unit III Neurologic System

• Explain the waveforms on the bedside monitor and how cleanse the site, local anesthetic, and possibly systemic this pressure is continually observed for signs of increased analgesia and sedation. External ventricular catheters ICP. In the case of increased ICP, the drain is opened to may be impregnated with antibiotics (e.g., clindamycin, drain CSF continuously or intermittently as prescribed to rifampin, and minocycline), or systemic antibiotics may alleviate the pressure. Rationale: This explanation pre- be given periprocedurally or prophylactically.4,22,27 sents to the patient and family a more realistic expectation of the events to come. Patient Preparation • Verify that the patient is the correct patient using two PATIENT ASSESSMENT AND identifi ers. Rationale: Before performing a procedure, the PREPARATION nurse should ensure the correct identifi cation of the patient for the intended intervention. 34 Patient Assessment • Ensure that the patient and family understand preproce- • Obtain a baseline assessment to include level of con- dural information. Answer questions as they arise, and sciousness, mental status, motor capability, sensation, reinforce information as needed. Rationale: Understand- cranial nerves, and vital signs. Rationale: This assessment ing of previously taught information is evaluated and provides baseline data. reinforced. • Obtain the patient ’ s medical and surgical history to include • Ensure that informed consent has been obtained. Ratio- use of aspirin, anticoagulants, prior craniotomies, the nale: Informed consent protects the rights of the patient presence of aneurysm clips, embolic materials, permanent and makes a competent decision possible for the patient. balloon occlusions, detachable coils, or a ventriculoperi- However, in emergency circumstances, time may not toneal shunt. Obtain laboratory results to assess coagula- allow for the consent form to be signed. tion status as needed. Rationale: The information obtained • Initiate IV access or assess the patency of the IV access. determines and guides future treatment based on the neu- Rationale: Readily available IV access is necessary if the rological examination results and evidence from radiology patient needs to be sedated or paralyzed or needs other and angiography. medications. • Assess for allergies. Rationale: Insertion of an external • Perform a preprocedure verifi cation and time out, if non- ventricular catheter requires the use of an antiseptic to emergent. Rationale: Ensures patient safety. 34

Procedure for Pressure Monitoring and Drainage Steps Rationale Special Considerations External Ventricular Drainage (EVD) System Assembly 1 . HH 2. Open the outer package of the Ensures sterile technique. sterile supplies. Apply sterile gloves, gown, and mask with eye shield.16 3. With aseptic technique, fl ush Prepares the drainage system for use; Use of a syringe fi lled with sterile, through the pressure tubing fl ushes air from the system. If air is preservative-free normal saline and drainage system with left in the tubing, it may alter the solution to prime the external preservative-free saline solution, numeric value or prevent the fl ow ventricular drainage system tubing turning the stopcocks as needed of CSF.9,23 rather than a bag of fl ush solution to prime the entire system. The preservative in normal saline may lessens the risk of fl ush solution Remove the syringe and replace cause cortical necrosis. 15 being administered through the with a sterile nonvented cap. ventricular catheter into the brain. In addition, the use of a fl ushless transducer at the zero reference on the drainage system eliminates lengthy tubing that may dampen the waveform ( Fig. 94-1 ). 4. Connect the end of the EVD Ensures that the system is secure and drainage system tubing to the is a sterile closed system. distal stopcock of the pressure monitor tubing ( Fig. 94-2 ) if not already included in the drainage system. Tighten all the connections.16,17,24 94 Intraventricular Catheter With External Transducer for CSF Drainage and ICP Monitoring 845

Figure 94-1 External ventricular drainage system with ﬂ ushless transducer at zero reference level. (Courtesy of Integra Lifesciences Corporation, Plainsboro, NJ.)

cm H2o Distal stopcock mm Hg

CSF sampling stopcock CSF sampling External drainage port system tubing Ventriculostomy Distal tip catheter Air fluid interface (zeroing stopcock)

Transducer with flush Drainage device system stopcock Sterile External Foramen cap auditory Drip Monroe meatus chamber (interventricular foramen) 4th ventricle Choroid plexus

External drainage collection bag

Figure 94-2 External ventricular drainage system. (Drawing by Paul Schiffmacher, Thomas Jef- ferson University, Philadelphia, PA.) 846 Unit III Neurologic System

Procedure for Pressure Monitoring and Drainage—Continued Steps Rationale Special Considerations 5. Close the clamp or stopcock Ensures the ability to measure hourly between the drip chamber and drainage in the drip chamber. the external ventricular drainage collection bag (see Fig. 94-2 ). 6. Replace all vented caps with Vented caps are used by the nonvented caps. manufacturer to permit sterilization of the entire system. These caps need to be replaced with sterile nonvented caps to prevent bacteria and air from entering the system. 7. After fl ushing the pressure The stopcock in this position readies Prevents the backfl ow of fl uid into the monitor tubing and the external the entire system for connection to drip chamber. ventricular drainage system the ventriculostomy catheter. tubing, turn the distal stopcock off to the distal tip of the pressure monitor tubing ( Fig. 94-3 ). 8. Position the reference level of the The relationship of the reference level The reference level of the drip chamber drip chamber as prescribed. of the drip chamber to the may need to be adjusted after anatomical reference point alters insertion of the ventricular catheter the rate of CSF drainage. and the initial ICP is obtained and is individualized for each patient based on etiology, pathophysiology, and management strategies. 9. Discard used supplies. Removes and safely discards used supplies. 10. HH Assisting With Insertion of an Intraventricular Catheter 1 . HH 2. Apply nonsterile gloves, gowns, Reduces transmission of and masks with eye shields. After microorganisms and body opening outer packaging, apply secretions; Standard Precautions. sterile gloves to handle sterile supplies. 3. Ensure the patient is in position Facilitates the insertion of the The usual position is supine, with the for ventricular catheter catheter. head of bed elevated. placement. Administer sedation and analgesia as prescribed and monitor patient per institutional standards for procedural sedation monitoring. 4. Assist as needed with the Reduces the transmission of The choice of povidone iodine or antiseptic preparation of the microorganisms into the ventricles. chlorhexidine as an antiseptic agent insertion site. is controversial.14,18 Both should be allowed to dry completely. Observe for initiation of CSF drainage, and obtain an opening ICP. Distal stopcock

To transducer Distal tip of pressure monitoring tubing

External ventricular Ventriculostomy drainage system catheter tubing Figure 94-3 Distal stopcock turned off to the distal tip of the pressure monitor tubing. (Drawing by Paul Schiffmacher, Thomas Jefferson University, Philadelphia, PA.) 94 Intraventricular Catheter With External Transducer for CSF Drainage and ICP Monitoring 847

Procedure for Pressure Monitoring and Drainage—Continued Steps Rationale Special Considerations 5. Connect the drainage/monitoring Establishes draining system. system to the distal tip of the catheter after it is inserted. 6. Assist as needed with application Reduces the risk of infection. of a sterile, occlusive dressing or as per hospital standards. Secure the catheter to minimize manipulation and the risk of inadvertent removal.16,25 (Level E * ) 7. Discard supplies. 8 . HH Connecting the EVD Transducer with Bedside Monitor 1. Turn on the bedside monitor. Prepares the monitor. 2. Plug a pressure cable into the The signal is transmitted to the appropriate pressure module or bedside monitor so that it may be port in the bedside monitor (see transmitted to the oscilloscope for Fig. 94-2 ). display. 3. Attach the pressure cable to the Prepares the equipment. transducer connection on the pressure tubing of the drainage system. 4. Turn on the ICP parameter. Visualizes correct waveform. 5. Set the appropriate scale for the It is necessary to visualize the The normal ICP for an adult is within measured pressure.27,29 complete waveform and to obtain the range of 0–15 mm Hg. 8,12 corresponding numerical values. Waveforms vary in amplitude, depending on the pressure within the system. 6. Set the monitor alarm limits for Goals for ICP management are ICP and CPP. individualized for each patient based on etiology, pathophysiology, and management strategies. Leveling the Transducer 1. Perform hand hygiene. 2 . PE 3. Position the patient in the supine Prepares the patient. The head of the bed is usually placed position with the head of the bed at 30 degrees to aid in increasing elevated as prescribed by the venous return. 12,27 physician, advanced practice nurse, or other healthcare professional.26,28,31 (Level E) 4. Place the air-ﬂ uid interface The external auditory meatus Some institutions use the tragus or a (zeroing stopcock) at the level of approximates the level of the line drawn from the outer canthus the external auditory meatus (see foramen of Monro (intraventricular of the eye.2,22 Follow institutional Fig. 94-2 ). 2,31 (Level B * ) foramen).2,8 policy. 5. Discard supplies. 6 . HH

* Level B: Well-designed, controlled studies with results that consistently support a speciﬁ c action, intervention or treatment. * Level E: Multiple case reports, theory-based evidence from expert opinions, or peer-reviewed professional orga nizational standards without clinical studies to support recommendations.

Procedure continues on following page 848 Unit III Neurologic System

Procedure for Pressure Monitoring and Drainage—Continued Steps Rationale Special Considerations Zeroing the Transducer 1 . HH Follow institutional standard. 2 . PE 3. Turn the transducer stopcock off Prepares the system for the zeroing to the patient. procedure. 4. If indicated for the drainage/ Allows the monitor to use Follow institutional standard. monitoring system in use: remove atmospheric pressure as a reference the nonvented cap from the for zero. stopcock, thus opening the stopcock to air. (Some drainage systems may not require removing a cap but simply adjusting the drip chamber to 0 mm Hg, pressing zero on the bedside monitor, and retuning the drip chamber to the level prescribed.) 5. Push and release the zeroing The monitor automatically adjusts Some monitors require that the zero button on the bedside monitor. itself to zero. Zeroing negates the be turned and adjusted manually. Observe the digital reading until effects of atmospheric pressure. it displays a value of zero. 6. Place a new, sterile, nonvented Maintains sterility. cap on the stopcock. 7. Turn the stopcock so that it is Permits pressure monitoring. open to the transducer. Observe the ICP waveform and the corresponding numerical value. 8. Discard used supplies. 9 . HH Monitoring Intracranial Pressure 1 . HH 2 . PE 3. Position the head of the bed as Allows for accurate and consistent Ensure that the EVD system is at the prescribed. monitoring of the ICP. prescribed level for ICP measurement (e.g., level with external auditory meatus). 4. Turn the distal stopcock off to the Decreases artifact from simultaneous external ventricular drainage drainage. Allows for accurate system ( Fig. 94-4 ).22 monitoring of the ICP. 5. Record the ICP value and Provides a value for ongoing The normal ICP waveform has at waveform per institutional assessment. Allows analysis of the least three distinct pressure standard. ICP waveform. oscillations or peaks. These are

referred to as P 1 , P2 , and P3 (see Fig. 92-2 ). 19,25

Distal stopcock

To transducer

Distal tip of pressure monitoring tubing

External ventricular Ventriculostomy drainage system catheter tubing Figure 94-4 Distal stopcock turned off to the external drainage system tubing. (Drawing by Paul Schiffmacher, Thomas Jefferson University, Philadelphia, PA.) 94 Intraventricular Catheter With External Transducer for CSF Drainage and ICP Monitoring 849

Procedure for Pressure Monitoring and Drainage—Continued Steps Rationale Special Considerations 6. Monitor and record ICP and CPP Assesses ICP waveform and values If continuous drainage is prescribed, as prescribed. and CPP value. the risk of overdrainage is increased. If the drainage system allows, turn the stopcock to simultaneously drain and to trend the ICP. Set alarms. To obtain an accurate ICP, the stopcock must be turned off to the drain with the catheter open to the transducer only and the waveform and numeric value of the ICP given time to stabilize. The waveform and numeric value of the ICP should correspond. Deviations in ICP and CPP may require immediate intervention and should be reported to the physician, advanced practice nurse, or other healthcare professional. If an EVD is in the monitoring position (and off to CSF drainage), special care must be paid to the bedside neurological examination with regard to the potential for deterioration. The catheter may become obstructed with clot, tissue, or protein. Note any changes in CSF fl ow. Notify the physician, advanced practice nurse, or other healthcare professional who may need to irrigate the catheter to reestablish patency. Other maneuvers may include turning or stimulating a cough. Some institutional policies may allow the critical care nurse to irrigate the catheter with a limited amount of preservative-free saline solution. Follow institutional standard. 7 . PE 8 . HH Draining CSF from the EVD 1 . HH 2 . PE 3. The physician, advanced practice If the physician, advanced practice Assess patency of the system when nurse, or other healthcare nurse, or other healthcare applicable by lowering the system professional will prescribe the professional prescribes the ICP to briefl y to assess for CSF dripping desired ICP parameter and the be maintained at < 15 mm Hg, into the burette (then return to reference level of the drip drainage of CSF will be initiated if ordered anatomical point).32 chamber. the patient ’ s ICP is > 15 mm Hg. 4. To drain the CSF, turn the distal Allows the fl ow of CSF from the Never leave a draining EVD stopcock of the pressure ventricles. unattended. Excessive drainage may monitoring tubing off to the cause overdrainage and a possible transducer ( Fig. 94-5 ).22 collapse of the ventricles, resulting in tearing of the bridging veins of the brain causing a subdural hematoma. Procedure continues on following page 850 Unit III Neurologic System

Distal stopcock

To transducer

Distal tip of pressure monitoring tubing

External ventricular Ventriculostomy drainage system catheter tubing Figure 94-5 Distal stopcock turned off to the transducer. (Drawing by Paul Schiffmacher, Thomas Jefferson University, Philadelphia, PA.)

Procedure for Pressure Monitoring and Drainage—Continued Steps Rationale Special Considerations 5. Allow 2–5 mL of CSF to enter Prevents overdrainage of CSF. Never leave a draining EVD the drip chamber (see Fig. 94-5 ). unattended. 6. When drainage is completed, turn Check the ICP value to determine If the patient’ s CSF is being the distal stopcock off to the whether the parameter is met. continuously drained, note and external ventricular drainage record the amount of drainage system (see Fig. 94-4) and record every hour. In general, no more the amount drained and the ICP than 20 mL, the amount of CSF value. produced in 1 hour,3 should be drained each hour. 7. If the goal was not met, repeat Allows gradual draining of CSF. Steps 3–5 until the ICP parameter is met. CSF Sampling 1 . HH 2. Obtain from a physician, Prepares for the test. CSF sampling may include glucose, advanced practice nurse, or other cell count, protein, culture and healthcare professional an order sensitivity, and gram stain. If a for a CSF sample, including the comparison of serum glucose and frequency. CSF glucose is prescribed, a serum glucose sample should be obtained at the same time as the CSF sampling. Normal CSF glucose is two thirds of blood glucose.3,6 3. Obtain the supplies for sampling: Prepares the equipment. sterile 3-mL syringes, CSF tubes, antiseptic solution, sterile gloves, mask with face shield, laboratory forms, and specimen labels. 4. Apply sterile gloves and mask Reduces the transmission of with face shield. microorganisms and body ﬂ uids; Standard Precautions. 5. Cleanse the CSF sampling port Reduces the transmission of Follow institutional standard. with an antiseptic solution ( Fig. microorganisms into the ventricles. 94-6 ). Allow solution to dry. 6. Turn the distal stopcock of the Allows for direct sampling of CSF pressure monitor tubing off to the from the ventriculostomy catheter. transducer and turn the drainage system stopcock off to the drop chamber (see Fig. 94-5 ). 94 Intraventricular Catheter With External Transducer for CSF Drainage and ICP Monitoring 851

CSF sampling port

CSF sampling stopcock

Figure 94-6 CSF sampling port. (Drawing by Paul Schiffmacher, Thomas Jefferson University, Philadelphia, PA.)

Procedure for Pressure Monitoring and Drainage—Continued Steps Rationale Special Considerations 7. Slowly withdraw two 1- to 2-mL Obtains the prescribed sample. One sample may be used for samples from the designated CSF laboratory studies, and the other Y-site or sampling port and inject for culture and Gram stain, if each into a specimen tube. If prescribed by the physician, resistance is met during advanced practice nurse, or other aspiration, notify physician, healthcare professional. Follow advanced practice nurse, or other institutional standards. healthcare professional. 8. Turn the distal stopcock to Continues monitoring and drainage as resume monitoring or open to prescribed. drainage as prescribed. 9. Label the CSF specimen tubes Prepares the specimen for analysis. and send to the laboratory for analysis. 10. Discard used supplies. Removes and safely discards used supplies. 1 1 . HH

Expected Outcomes Unexpected Outcomes • Aseptic drainage system21,25,27 • Loose connections within the external ventricular • Air-fl uid interface of the transducer is leveled at the drainage system foramen of Monro for accurate ICP and CPP • Stopcocks left open to air without nonvented caps monitoring 22,26,28 • Air bubbles within the system23 • The monitoring system is zeroed • CSF infection 1,10,30 • Drainage chamber at prescribed level • CSF leak • Intermittent or continuous drainage as prescribed • Lack of CSF fl ow6 • Accurate and reliable monitoring of ICP and CPP22,26,28 • Dislodgment or occlusion of the EVD • Continuous fl ow of CSF when drainage is initiated; • Headache from overdrainage31 appropriate amount of CSF drainage22,26,28 • Pneumocephalus from overdrainage • Immediate management of increased ICP and • Rebleed from subarachnoid hemorrhage13,21 decreased CPP22,26,28 • Subdural hematoma from overdrainage27 • Improvement or stabilization of neurological • EVD-related hemorrhage27 function 22,28,31 • Herniation from underdrainage or overdrainage Procedure continues on following page 852 Unit III Neurologic System

Patient Monitoring and Care Steps Rationale Reportable Conditions These conditions should be reported if they persist despite nursing interventions. 1. Monitor each of the following Assesses neurological status. • Any gradual or sudden increase in parameters continuously or the ICP, with or without intermittently as prescribed: ICP, accompanying neurological CPP, and CSF drainage, amount, changes color, clarity, and patency of the • Lack of drainage in the presence of system. signifi cantly increased ICP requires immediate reporting to the physician, advanced practice nurse, or other healthcare professional; this may indicate an occlusion of the catheter 21,27 • Lack of drainage in the presence of signifi cantly increased ICP may also indicate occlusion of the drainage system from persistent contact of CSF catheter with the ventricular wall8 • Persistent large volumes of CSF may indicate the need for a CSF shunt 30 2. Zero the external ventricular Ensures the accuracy of the drainage system during the initial monitoring process. setup or before insertion, then after insertion and again if connections between the transducer and the monitoring cable become dislodged, if connections between the monitoring cable and the monitor become dislodged, and when the values do not fi t the clinical picture. 3. During position changes, clamp Minimizes the risk for underdrainage, • Increase or decrease in CSF the EVD. After changing the overdrainage, or erroneous ICP drainage patient ’ s position, maintain the values. • The inability to obtain CSF reference level of the EVD at the drainage external auditory meatus and • Changes in ICP or neurological ensure system is patent. assessment 4. Maintain the reference level of The relationship of the reference for • Underdrainage the drip chamber as prescribed. CSF drainage and ICP monitoring • Overdrainage level of the drip chamber to the anatomical reference point alters the rate of CSF drainage. 5. Check the system every hour and Ensures that all connections are as needed. tightly secured and that no cracks occur in the system. Ensures that the system is closed with nonvented caps on all stopcocks. Ensures that the system is free of air bubbles. 23 94 Intraventricular Catheter With External Transducer for CSF Drainage and ICP Monitoring 853

Patient Monitoring and Care —Continued Steps Rationale Reportable Conditions 6. Set the alarm parameters relative Provides immediate alarm for high • Changes in ICP or neurological to the ICP and CPP goals pressures (and an immediate alarm assessment established by the physician, for low pressures associated with advanced practice nurse, or other inadvertent overdrainage). healthcare professional. 7. All drainage should be measured Assesses CSF drainage. Amount, • Increase or decrease in CSF and recorded as part of the intake color, and character should be drainage; change in CSF color, and output. noted.26 presence of blood or blood-tinged CSF 8. If continuous drainage is used, Assesses CSF drainage. • Increase or decrease in CSF record and monitor the output drainage; underdrainage or every 1–2 hours. Maintain the overdrainage reference point at the foramen of Monro. 9. Change the dressing at the Maintains sterility and provides an • Signs or symptoms of infection insertion site daily or as opportunity for insertion site • Loosened sutures prescribed with aseptic technique. assessment.24 Follow institutional standard. 10. Change bag and drainage system Practices for changing CSF drainage • Inadvertent disconnection as needed by institutional collection device vary considerably. standard. Maintain closed system. 11. Follow institutional standard Identiﬁ es need for pain interventions. • Continued pain despite pain for assessing pain. Administer interventions analgesia as prescribed ( Fig. 94-7 ).

Documentation Documentation should include the following: • Initial opening ICP and CPP • Insertion site assessment • Level of the drip chamber and anatomical landmark • Hourly to every 2 hours output or amount drained for zeroing intermittently22,29 • Patency of drainage system • Hourly ICP and CPP22,29 • Analysis of waveform19,26,28,29 • Neurological assessment22,29 • Description of CSF to include amount, clarity and • Site care and change of drainage system or bag color • Pain assessment, interventions, and evaluation 854 Unit III Neurologic System

Monitoring ICP with a Ventricular Drain

To Drain CSF To drip chamber • Master System Stopcock Transducer system is off to the transducer Transducer Stopcock • Drainage line is open between the patient and Master the drip chamber System Stopcock • When the stopcock is open to drain it is critical that neither the height of the patient nor that of the drainage system be To patient changed to avoid over drainage of CSF

To Zero Transducer To drip • Requires hand hygiene, Transducer chamber sterile gloves and new Transducer system sterile dead-ender Stopcock • Turn the Transducer Master Stopcock off to the patient System (off to the Master System Stopcock Stopcock) • Remove dead-ender cap from side port of Transducer Stopcock To patient • The Transducer is OPEN TO AIR and isolated from any pressures • Press ZERO on the ICP monitor • Replace dead-ender cap with NEW STERILE CAP and turn stopcock back OFF to side port

To Monitor ICP To drip • Turn the Master System Transducer chamber Stopcock off to the drip Transducer system chamber Stopcock • The drainage line is open Master between the patient and the System transducer Stopcock

To patient

NEVER! To drip chamber • NEVER turn the stopcock Transducer system open three ways to try to Transducer drain and monitor at the Stopcock same time! • This gives a false ICP reading – the system is open to drain and therefore also open to air Figure 94-7 Alternate external ventricular drainage monitoring system. (Drawing by To patient Lorna Prang, Littleton, CO). 94 Intraventricular Catheter With External Transducer for CSF Drainage and ICP Monitoring 855

References and Additional Readings For a complete list of references and additional readings for this procedure, scan this QR code with any freely available smartphone code reader app, or visit http://booksite.elsevier.com/9780323376624 .