assessing and managing patients with chronic subdural hematoma · acute-on-chronic subdural...

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RUBY JACOBS, age 84, arrives at the emergency department with a headache, which she says has got- ten worse over the past week de- spite taking acetaminophen. Her past medical history includes atri- al fibrillation managed with meto- prolol 50 mg b.i.d. and warfarin 5 mg daily. She responds to voice but is oriented to name only. Her speech is slurred and she has diffi- culty finding the right words. She reports feeling “woozy and tired.” Her daughter states that her moth- er had a “fainting spell” several weeks ago and has become con- fused and lethargic over the past few days. A 12-lead electrocardiogram (ECG) shows atrial fibrillation with a ventricular rate of 62 beats/ minute. Blood pressure (BP) is 116/54 mm Hg; her standing BP, 102/50 mm Hg. Mrs. Jacobs’s labora- tory results are within normal ranges except for her International Normalized Ratio (INR) of 2.5, which is therapeutic for anticoagu- lation. Given her admitting symp- toms and altered neurologic status, the physician orders a noncontrast computed tomography (CT) scan of the head, which shows a right-sided acute-on-chronic subdural hematoma (SDH) with a 2-mm midline shift. Mrs. Jacobs is trans- ferred to the local trauma center for definitive management of her head bleed. In SDH, blood accumulates in the space between the dural and arachnoid membranes surrounding the brain. Bridging vessels that cross this space channel blood from the brain to the dural sinuses. Dam- age to these vessels commonly leads to subdural bleeding. Frequently stemming from a traumatic event, SDH is one of the deadliest brain injuries. Among people older than age 65, falls are the most common mecha- nism. But other factors can contribute to SDH in old- er adults, including anti- coagulant and an- tiplatelet medications to treat chronic med- ical conditions (such as atrial fibrillation, heart valve replace- ment, coronary ar- tery disease, and deep vein thrombo- sis). A history of anticoagulant and antiplatelet thera- py is especially significant for chronic SDH. One retro- spective study found that among more than 200 pa- tients admitted with chronic SDH, 39% were taking anticoag- ulants, antiplatelets, or a combination at the time of diagnosis. Types of SDH SDHs are categorized by the inter- vals between the precipitating event, symptom onset, and appear- ance of the blood in the subdural space, as shown on CT. An SDH may be acute, chronic, or acute on chronic. With an acute SDH, bleeding fills Assessing and managing patients with chronic subdural hematoma More common in the elderly, chronic subdural hematoma may be mistaken for stroke. By Mark Bauman, MS, RN, CCRN, and Tammy Russo McCourt, BSN, RN, CCRN 38 American Nurse Today Volume 9, Number 9 www.AmericanNurseToday.com

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RUBY JACOBS, age 84, arrives atthe emergency department with aheadache, which she says has got-ten worse over the past week de-spite taking acetaminophen. Herpast medical history includes atri-al fibrillation managed with meto-prolol 50 mg b.i.d. and warfarin 5 mg daily. She responds to voicebut is oriented to name only. Herspeech is slurred and she has diffi-culty finding the right words. Shereports feeling “woozy and tired.”Her daughter states that her moth-er had a “fainting spell” severalweeks ago and has become con-fused and lethargic over the pastfew days.

A 12-lead electrocardiogram(ECG) shows atrial fibrillation witha ventricular rate of 62 beats/minute. Blood pressure (BP) is116/54 mm Hg; her standing BP,102/50 mm Hg. Mrs. Jacobs’s labora-tory results are within normalranges except for her InternationalNormalized Ratio (INR) of 2.5,which is therapeutic for anticoagu-lation. Given her admitting symp-toms and altered neurologic status,the physician orders a noncontrastcomputed tomography (CT) scan ofthe head, which shows a right-sidedacute-on-chronic subduralhematoma (SDH) with a 2-mmmidline shift. Mrs. Jacobs is trans-ferred to the local trauma centerfor definitive management of herhead bleed.

In SDH, blood accumulates inthe space between the dural andarachnoid membranes surroundingthe brain. Bridging vessels thatcross this space channel blood fromthe brain to the dural sinuses. Dam-age to these vessels commonlyleads to subdural bleeding. Frequently stemming from a

traumatic event, SDH is one of thedeadliest brain injuries. Amongpeople older than age 65, fallsare the most common mecha-nism. But other factors cancontribute to SDH in old-er adults, including anti-coagulant and an-tiplatelet medicationsto treat chronic med-ical conditions (suchas atrial fibrillation,heart valve replace-ment, coronary ar-tery disease, anddeep vein thrombo-sis). A history of anticoagulant andanti platelet thera-py is especiallysignificant forchronic SDH.One retro-spective studyfound that amongmore than 200 pa-tients admitted withchronic SDH, 39%were taking anticoag-ulants, antiplatelets,or a combination atthe time of diagnosis.

Types of SDHSDHs are categorized by the inter-vals between the precipitatingevent, symptom onset, and appear-ance of the blood in the subduralspace, as shown on CT. An SDHmay be acute, chronic, or acute onchronic.With an acute SDH, bleeding fills

Assessing and managing patients with chronic subdural

hematomaMore common in the elderly, chronic subdural

hematoma may be mistaken for stroke.

By Mark Bauman, MS, RN, CCRN, and Tammy Russo McCourt, BSN, RN, CCRN

38 American Nurse Today Volume 9, Number 9 www.AmericanNurseToday.com

www.AmericanNurseToday.com September 2014 American Nurse Today 39

the subdural space rapidly, com-pressing brain tissue. This typicallycauses brain swelling, herniation,and eventually death. An estimated50% of brain injuries and 60% ofdeaths in brain-injured patients re-sult from acute SDHs; many sur-vivors suffer severe neurologic dis-ability.

Chronic SDH may follow a mi-nor brain injury or certain proce-dures (such as lumbar puncture) ormay arise spontaneously, especiallyin persons with cerebral atrophy. Itmay go unnoticed for weeks ormonths.

Acute-on-chronic SDH (Mrs. Ja-cobs’s diagnosis) refers to chronicSDH that has been present for sev-eral weeks, with recent additionalcollection of hemorrhagic blood.Presenting signs and symptoms re-semble those of an acute SDH. Chronic SDH is primarily a dis-

ease of the elderly. Age-related at-rophy reduces brain volume, whichwidens the subdural space andstretches the bridging vessels, mak-ing them more fragile and prone torupture. Also, an atrophied braintends to move more within the cra-nium, resulting in higher potentialshearing forces on the bridgingvessels even with relatively minorforces. Up to half of elderly per-sons who fall sustain brain injuriescaused by indirect forces (tearingof the bridging vessels from brainmotion) rather than direct headtrauma. A widened subdural spacefrom cerebral atrophy usually givesthese hematomas room to expandwithout causing intracranial pres-sure to increase, while at the sametime preventing pressure from ris-ing high enough to cause tampon-ade of the bleeding vessels.

Signs and symptoms of chronicSDHTypically, chronic SDH is slow todevelop and causes nonspecificsigns and symptoms, whose severi-ty varies with hematoma size, loca-tion, and thickness. Persistent

headache is a common complaint.Neurologic status changes (such aslethargy, confusion, gait and bal-ance disturbances, recurrent falls,or seizures) usually prompt the vic-tim to seek medical care. As chronic SDH expands and

exerts more pressure on the brain,level of consciousness (LOC) dete-riorates and focal neurologicdeficits (such as hemiparesis ordysphasia) may arise. Often con-fused for stroke, these develop-ments warrant emergency surgery.

Diagnosing chronic SDHSuspicion of chronic SDH is basedon patient risk factors and history.A noncontrast-enhanced CT headscan provides a definitive diagno-sis, determining SDH location, size,and thickness and measuring mid-line shift. Hematoma staging com-monly hinges on density of bloodin the subdural space and timingrelative to the precipitating event.

Managing chronic SDHNo established standard of care ex-ists for chronic SDH management.

Surgical options include percuta-neous twist-drill craniostomy (TDC),operative burr-hole evacuation, andcraniotomy. Debate surrounds notjust the surgical approach but alsothe number of burr holes, saline ir-rigation of the cavity, postoperativedrain use, and postprocedural pa-tient position and mobility. For elderly patients with signifi-

cant comorbidities, a minimally in-vasive bedside TDC eliminates theneed for general anesthesia. A re-cent meta-analysis found bedsideTDC offers the same efficacy as op-erative burr-hole evacuation. Cran-iotomy (bone flap removal with re-placement) remains the procedureof choice for congealed blood inthe subdural space and recurringhematomas, estimated to occur inup to 25% of cases after less inva-sive management.

Bedside TDC Because many patients with chron-ic SDH are receiving anticoagulantsor antiplatelet agents, laboratorystudies (prothrombin time, partialthromboplastin time, INR, and acomplete blood count) should beobtained and values normalizedbefore TDC. Fresh frozen plasma,vitamin K, or prothrombin complexconcentrate may be given to re-verse warfarin; a platelet transfu-sion may be administered emer-gently to manage patients receivingantiplatelet drugs, such as aspirinor clopidogrel. Be aware that an-tiplatelet therapy impairs the func-tion but not quantity of platelets. Aplatelet transfusion replenishesfunctional platelets and is an ac-cepted reversal agent for an-tiplatelet agents, independent ofthe patient’s platelet count. Neweranticoagulants, such as directthrombin inhibitors and factor Xainhibitors, are more problematic toreverse. They should be withdrawnimmediately and institutional algo-rithms or treatment guidelinesshould be implemented. Because TDC involves cannula-

Suspicion of chronicSDH is based on patient

risk factors and

history.

40 American Nurse Today Volume 9, Number 9 www.AmericanNurseToday.com

tion of the subdural space, care-givers must adhere strictly to asep-tic precautions, including scalppreparation, antibiotic prophylaxis,and sterile garb and draping. Mostpatients can be managed with localanesthesia, but procedural medica-tions (including sedatives) may beneeded to calm a confused or anx-ious patient. In this case, cliniciansmust adhere to facility policies andprocedures for moderate sedation.Use of end-tidal carbon monoxide(ETCO2) monitoring may provebeneficial given the typical patientpopulation and risks of sedation inthe elderly. To begin, the neurosurgeon

makes a small incision through thescalp to expose the skull and, us-ing a twist drill, takes an angledapproach through the bone to ac-cess the subdural space. When thedural membrane is fully breached,old blood flows freely. Dependingon the system used, either a ven-tricular catheter is advanced via theburr hole into the clot or a subdur-al evacuation system with closed-system drainage is threaded inplace. If a ventricular catheter is being

used, it is tunneled under the scalpto help prevent infection and dis-lodgment. Then it’s connected toan external drainage system, whichis lowered at least 20 cm below thepatient’s head to create the pres-sure gradient needed to promotedrainage. To avoid wetting the airfilter in the collection chamber, thecollection system must be kept up-right to maintain a functionaldrainage system. Expect the physician to order a

postprocedural head CT scan toconfirm drain placement and ex-clude complications, such as brainlaceration or epidural bleeding.Typically, the drain stays in placefor 24 to 48 hours. Every hour,monitor drainage for amount andcharacteristics and perform a fo-cused neurologic exam. Know thatdrainage cessation may indicate

catheter clotting, which necessitatesphysician intervention (manual as-piration or catheter flushing withpreservative-free normal saline so-lution) to restore flow. Serial CTscans aid in assessing drainage ad-equacy. Rarely, a chronic SDH maybe evacuated fully via subduralcatheter drainage. However, reduc-ing its size may promote the natu-ral absorption process.

Patient positioning duringdrainagePositioning during drainage is con-troversial. Because chronic SDHsrarely increase intracranial pressure,many neurosurgeons favor thesupine position with the head ofthe bed flat to encourage drainageand brain reexpansion. Enforcedbed rest in elderly patients maylead to pneumonia, deep venousthrombosis, and aspiration. A 2007study suggested better outcomes(without a clinically significant risein complications) are achieved withthe supine position, but more re-cent studies contradict these find-

ings. At our hospital, the practice isto maintain the supine, flat head-of-bed position except for meals (un-less contraindicated). During thistime, the subdural drain is clampedand the patient is permitted to sit ina high Fowler’s position.

TDC complicationsPotential complications of TDC in-clude bleeding, infection, pneumo-cephaly, a bleed in the opposingbrain hemisphere, and herniation.Simple pneumocephaly (air in thesubdural space) results from lackof counterpressure on the evacuat-ed subdural space; typically, CSFfills the space over time and miti-gates this effect. Tension pneumo-cephaly occurs when air enters thesubdural space and creates pres-sure within the cranial vault. As airexerts pressure on surroundingbrain structures, the patient’s LOCmay decline. Considered a medicalemergency, tension pneumo-cephaly almost always warrants acraniotomy for decompression.

Nursing considerationsNursing care for a patient who willundergo a TDC include preparingthe patient and family for the pro-cedure, obtaining informed con-sent, and obtaining baseline labora-tory values (with appropriateinterventions taken to normalizevalues). Because many patientswith chronic SDH have significantcardiac comorbidities, continuousECG and pulse oximetry should beused. If the patient will receivemoderate or procedural sedation,ETCO2 monitoring should be con-sidered. Obtain a thorough neurologic

baseline assessment for comparisonwith subsequent neurochecks. Al-though procedural pain usually canbe managed with local anesthesia,many patients may experience anx-iety and some may have underly-ing delirium, requiring judicioususe of anxiolytics or antipsychoticagents. In this case, decrease sen-

TDC complicationsinclude bleeding, infection,

pneumocephaly, a bleed

in the opposing brain

hemisphere, and

herniation.

sory stimuli, such as by turning offoverhead lights and minimizingnoise. Placing a pressure-relievingmattress or an air cushion underthe patient’s sacrum is recommend-ed, as mobility is limited while thedrain is in place. If the patient isallowed to sit upright for meals,encourage him or her to use incen-tive spirometry and perform cough-ing and deep breathing during thistime. Monitor and documentdrainage output, including volumeand character, every hour; reportchanges to the neurosurgeon im-mediately. Postoperatively, teach the patient

and family about the need for serialCT head scans, the prospect of sur-gical intervention in the event of aworsening CT scan or neurologicexam, and the need for compre-hensive evaluation by the rehabili-tation team to assess for neurologicdeficits after the procedure.

Scenario continuedWhen Mrs. Jacobs arrives at thetrauma center, the neurosurgeonreviews her CT scan. Based on herpresenting symptoms and cardiachistory, he decides to perform abedside percutaneous TDC withdrain insertion. Before the proce-dure, Mrs. Jacobs requires 6 unitsof fresh frozen plasma to normalize

her INR. Using moderate sedation,the neurosurgeon inserts the sub-dural drain without adverse events.Over the next 24 hours, 150 mL ofliquefied blood is evacuated. Thenthe drain is removed. The CT scanshows significant reduction in thevolume of blood removed.

During her hospital stay, Mrs. Ja-cobs has episodes of symptomaticbradycardia with heart rates in the40s. A cardiology consult leads tomedication revision to manage herchronic atrial fibrillation. Physical,speech, and occupational therapistsevaluate her for functionality andrecommend her for home dischargewith outpatient physical therapy. O

Visit www.AmericanNurseToday.com/Archives.aspx for a chart on SDH categoriesand a list of selected references.

The authors are senior clinical nurses at the R AdamsCowley Shock Trauma Center at the University ofMaryland Medical Center in Baltimore.

Postoperatively, teachthe patient and family

about the need for serialCT head scans.

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Subdural hematomas (SDHs) may be acute, chronic, or acute on chronic. This chart differentiates the three types.

Type Description Appearance Symptom onset after Signs and precipitating event symptoms

Acute Usually results from Clotted blood, which Within 72 hours • Decreased LOCbrain laceration with appears hyperdense • Hemiparesisinjury to small bridging (white) on CT • Unilateral pupil dilationveins of subdural space • Extraocular eye movement

• Paralysis• Cranial nerve dysfunction, causing diminished or absent pupillary light response or corneal reflex

Chronic Usually occurs in elderly Fluid mass with classic 2 weeks or longer Interval when patient appearspersons or chronic drinkers “crankcase oil” to recover, followed by with brain atrophy; often appearance, which progressive deterioration with linked to falls appears hypodense drowsiness, inattention,

(black) on CT personality changes, and headache progressing to hemiparesis, pupil changes, and decreased mental status

Acute on Preexisting blood Heterogeneous 2 weeks or longer Similar to acute SDHchronic accumulation with new appearance on CT;

bleeding superimposed; may cause layering usually caused by of hyper- and traumatic injury or brain hypodense fluidatrophy

Key: CT: computed tomography; LOC: level of consciousness

Classifying subdural hematomas

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