Study guide
17.3 Vascular Access, Thoracic Echo, and Lung Ultrasound (02.J–L)
ABIM Neurocritical Care Subspecialty Certification Exam
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1 Introduction & Exam Overview
1.1 Current Exam Facts 1.2 Eligibility, Practice Pathway, and the IM Training Route 1.3 Format, Scoring, Pearson VUE, and Score Reports 1.4 How to Use This Independent Study Guide
2 ICU Neurologic Exam, Cerebral Physiology, and CSF
2.1 Neurological Examination in the ICU 2.2 Cerebral Physiology, ICP, CBF, and Autoregulation 2.3 CSF Physiology
3 Core Neuropharmacology
3.1 Osmotic Agents 3.2 Anti-Seizure Drugs 3.3 Anesthetics, Sedatives, Analgesia, and Paralytics 3.4 Antihypertensives, Vasopressors, and Inotropes
4 Reperfusion Drugs, Airway, and Ventilation
4.1 Thrombolytics, Anticoagulants, and Antiplatelets 4.2 Reversal of Anticoagulation After Acute Hemorrhage 4.3 Airway Management and Tracheostomy 4.4 Mechanical Ventilation
5 Hemodynamics and Shock
5.1 Hemodynamic Monitoring 5.2 IABP, Temporary VADs, LVAD, and ECMO 5.3 Diagnosis and Management of Shock
6 Nutrition, Temperature, and ICU Prophylaxis
6.1 Nutrition (01.J) 6.2 Temperature Control (01.K) 6.3 ICU Prophylaxis, Delirium, and Early Mobility (01.L)
7 General Trauma
7.1 Emergency Evaluation of Polytrauma, Chest, and Abdominal Trauma 7.2 Long-Bone Fractures and Fat Embolism 7.3 Burns, Electrical Injury, and Hanging/Strangulation
8 Pulmonary Critical Care
8.1 Pulmonary Physiology and ARDS (01.N.1–2) 8.2 PE, Pneumonia, and Pulmonary Edema (01.N.3, 7–8) 8.3 COPD, Asthma, PAH, and Bronchoscopy Basics (01.N.4–6, 9)
9 Cardiovascular Critical Care
9.1 Cardiovascular Physiology, Stress Cardiomyopathy, ACS, and Valves 9.2 Arrhythmias and Pacing 9.3 Acute Aortic Dissection and Cardiac Ultrasound
10 Renal and Infectious Disease
10.1 AKI, RRT, and Renal Drug Dosing 10.2 Acid-Base and Electrolyte Disorders 10.3 Severe Sepsis, Septic Shock, and Infective Endocarditis 10.4 Antimicrobial Use and Infection in the Immunosuppressed
11 Endocrine and Salt-Water Disorders
11.1 Pituitary Apoplexy, DI, and Panhypopituitarism (01.R.1–4) 11.2 SIADH and Cerebral Salt Wasting (01.R.5–6) 11.3 Thyrotoxicosis, Myxedema, Adrenal Crisis, and Dysglycemia (01.R.7–9)
12 Gastrointestinal Critical Care
12.1 GI Physiology, Acute Abdomen, Bleed, Ileus, and Perforation (01.S.1–5) 12.2 Mesenteric Ischemia and Abdominal Compartment Syndrome (01.S.6–7) 12.3 Fulminant Liver Failure, Cirrhosis Decompensation, and Hepatic Dosing (01.S.8–10)
13 Hematologic Disorders
13.1 Anemia, Transfusion, Thrombocytopenia, Coagulopathy, and DIC (01.T.1–4) 13.2 VTE in the Neuro ICU (01.T.5) 13.3 Chemo/Immune, SCT, CAR-T, Sickle Cell, and TMA (01.T.6–10)
14 Neuroimaging
14.1 CT of Brain and Spine 14.2 MRI and CT/MR Perfusion 14.3 Noninvasive Angiography and Catheter Angiography
15 EEG, EMG, and CSF Analysis
15.1 EEG, Standard and Processed (02.B) 15.2 Basic EMG Interpretation (02.G) 15.3 CSF Analysis (02.H)
16 ICP, TCD, and Multimodality Monitoring
16.1 ICP Monitoring (02.C) 16.2 Transcranial Doppler (02.D) 16.3 Brain-Tissue Oxygen and Multimodality Monitoring (02.E–F)
17 Brain Death and Bedside Procedures
17.1 Brain Death Prerequisites and Clinical Exam (02.I) 17.2 Apnea Testing and Ancillary Studies (02.I) 17.3 Vascular Access, Thoracic Echo, and Lung Ultrasound (02.J–L)
18 Coma, Anoxia, and Intracranial Hypertension
18.1 Coma and Other States of Altered Consciousness (03.A) 18.2 Global Anoxia-Ischemia and Post-Resuscitation Encephalopathy (03.A.1) 18.3 Toxidromes, ICU Delirium, and Hypertensive Encephalopathy (03.A.2–4) 18.4 Intracranial Hypertension as a Disease State (03.B)
19 Acute Ischemic Stroke
19.1 IV Reperfusion Therapy (03.C.3) 19.2 Mechanical Thrombectomy Windows and Imaging Selection (03.C.3) 19.3 Malignant Hemispheric Infarction and Basilar Artery Occlusion (03.C.1–2)
20 Intraparenchymal Hemorrhage
20.1 Intracerebral Hematoma (03.D.1) 20.2 Cerebellar Hematoma (03.D.2) 20.3 Intraventricular Hemorrhage (03.D.3)
21 SAH, CVST, and Spinal Cord Infarction
21.1 Aneurysmal Subarachnoid Hemorrhage (03.E.1) 21.2 Non-Aneurysmal SAH (03.E.2) 21.3 Cerebral Venous Sinus Thrombosis (03.F) 21.4 Spinal Cord Infarction (03.G)
22 Vascular Anomalies and Traumatic Brain Injury
22.1 Unruptured Aneurysm, Cavernoma, AVM, and Dural AVF (03.H) 22.2 Diffuse Axonal Injury and Cerebral Contusions (03.I.1–2) 22.3 Epidural Hematoma, Subdural Hematoma, and Penetrating Injury (03.I.3–4, 7) 22.4 Arterial Dissection and Carotid-Cavernous Fistula (03.I.5–6)
23 Spine, Hydrocephalus, and CNS Infection
23.1 Spinal Cord Injury, Central Cord, and Neurogenic Shock (03.J) 23.2 Unstable Spine Fractures (03.K) 23.3 Hydrocephalus and CSF Diversion (03.L) 23.4 Acute CNS Infections (03.M)
24 Seizures and Neuromuscular Emergencies
24.1 Status Epilepticus and Seizures (03.N) 24.2 Guillain-Barré Syndrome (03.O.1) 24.3 Myasthenic Crisis (03.O.2) 24.4 Motor Neuron Disease, Acute Myopathies, Rhabdomyolysis, and CINM (03.O.3–6)
25 Inflammatory Disease, Neuro-Oncology, and Special Populations
25.1 Fulminant Demyelinating Diseases (03.P) 25.2 Autoimmune Encephalitis and Acute Autonomic Hyperactivity (03.Q–R) 25.3 Neuro-Oncology and Treatment Complications (03.S) 25.4 Pregnancy/Post-Partum, Post-Transplant, and Pediatric Patients (03.T–U)
26 Neurosurgical and Perioperative Complications
26.1 Postoperative Seizures, Hemorrhage, Ischemia, and Hyperperfusion (04.A, C, D, H) 26.2 Infection, CSF Leak, and Pneumocephalus (04.B, E, F) 26.3 Complications of EVD and Lumbar Drain (04.G, I)
27 Ethics, Prognostication, and Organ Donation
27.1 Communication, Decision-Makers, Advance Directives, and DNR (05.A, B, G) 27.2 Uncertainties of Prognostication and the Self-Fulfilling Prophecy (05.C) 27.3 Palliative Care, Withdrawal, Withholding, and Futility (05.D–F) 27.4 Donation After Cardiac Death and Care of the Organ Donor (05.H–I)
17.3 Vascular Access, Thoracic Echo, and Lung Ultrasound (02.J–L)
Key Takeaways Explain This Topic AI
Choose a central venous site for the neuro ICU patient with ICP, coagulopathy, and infection risk in mind: internal jugular veins are ultrasound-friendly but can impair cerebral venous drainage if occluded; subclavian access has more pneumothorax; femoral access spares the neck when ICP is high or the collar stays on.
Ultrasound guidance is the default for internal jugular central lines and for radial arterial lines; confirm venous location before dilation and confirm arterial waveform and distal perfusion after an arterial catheter.
Lung ultrasound: A-lines with sliding suggest aerated lung; B-lines mark interstitial syndrome; absent sliding plus a lung point diagnoses pneumothorax at that location; absent sliding without a lung point is not automatically a pneumothorax.
Bedside thoracic echocardiography looks for tamponade physiology, left and right ventricular size and function, and inferior vena cava behavior as a rough right-atrial-pressure clue — not as a single-number volume protocol in every ventilated patient.
Complications to name on the examination are pneumothorax, arterial puncture, catheter-related bloodstream infection, venous thrombosis with possible effects on ICP, tamponade from wire injury, and limb ischemia from arterial lines.
Last updated: September 2026
Procedures that keep the brain perfused
Quick Answer: In the neuro ICU, a central venous catheter (CVC) is a site-choice problem: internal jugular (IJ) is ultrasound-friendly but sits in the cerebral venous outflow; subclavian lowers some infection risk and raises pneumothorax risk; femoral spares the neck when ICP is high or a cervical collar is on, at the price of thrombosis and infection. Place arterial lines for beat-to-beat pressure and blood gas access, preferably ultrasound-guided . Lung ultrasound separates A-lines (aerated) from B-lines (interstitial) and uses the lung point for pneumothorax. Thoracic echo looks for tamponade , left ventricular (LV) and right ventricular (RV) failure, and inferior vena cava (IVC) plethora.
Independent ExamFinch teaching in this section covers vascular access, thoracic echocardiography, and lung ultrasound listed under Diagnostic studies and procedural skills in the ABPN Content Specifications. It is not an ultrasound-credentialing course and not an ABIM product. The examination wants which site in a high-ICP patient, which lung sign after a subclavian attempt, and which echo view explains shock after a wire went too far.
Central venous access: three veins, three neuro-ICU prices
A CVC is for vasopressors, hypertonic saline, central venous saturation sampling, and emergency resuscitation when peripheral veins fail. Ultrasound guidance is the default for IJ cannulation: it reduces carotid puncture and failed attempts. Identify the vein as compressible and non-pulsatile, watch the needle tip enter the lumen, confirm venous blood color and pressure if there is any doubt, and never dilate until you are sure you are not in the carotid. A manometry column or a transduced waveform is cheap insurance. After dilation, confirm tip position in the cavoatrial junction on radiograph or by ultrasound/ECG-tip methods used in your unit.
Site Advantages Neuro-ICU-specific costs Classic mechanical complications
Right IJ Straight path to the SVC; excellent ultrasound window Large catheter, hematoma, or thrombosis can impede cerebral venous drainage and raise ICP ; left IJ is more tortuous and can injure the thoracic duct Carotid puncture, hematoma that threatens the airway
Subclavian (infraclavicular) Historically lower CLABSI than femoral; out of the way of a cervical collar Pneumothorax; harder ultrasound; landmark technique still used in arrest Pneumothorax, hemothorax, pinch-off, arterial puncture that is hard to compress
Femoral Compressible; no pneumothorax; does not occupy the jugulars when ICP is high or herniation is a concern Higher infection and DVT with prolonged dwell; dirty in groin trauma Femoral artery puncture, retroperitoneal spread if you go too high
ICP and venous drainage. Cerebral venous blood leaves largely through the jugulars . A tight hematoma, a large-bore dialysis catheter, or IJ thrombosis can raise cerebral venous pressure and therefore ICP . When ICP is already a crisis, many neurointensivists prefer femoral or subclavian access rather than parking a stiff catheter in the only remaining jugular. That is a physiology choice, not a prohibition: an ultrasound-guided IJ is still appropriate when it is the safest emergency vein and the neck is not the problem. Do not place bilateral IJ catheters “because we might need two lumens” in a mass-lesion patient.
Coagulopathy. A compressible site (femoral, IJ) is safer than a non-compressible subclavian when platelets or INR are hostile. Reverse what you can before an elective line; an arterial bleed into the neck after carotid puncture is an airway emergency.
Dialysis catheters in the right IJ are standard for CRRT , but in high ICP they are the same jugular-occupancy problem. If the brain is the organ that will herniate this hour, femoral dialysis access is often the less bad option for a few days.
Arterial lines
Neuro ICU indications are labile blood-pressure targets (ischemic stroke after lytics, SAH, ICP/CPP titration), frequent ABGs, and unreliable non-invasive cuffs in shock or arrhythmia. Radial is first-line: collateral flow via the palmar arch, easy ultrasound, and a compressible site. The modified Allen test is traditional and insensitive; ultrasound of the ulnar artery and of flow after radial occlusion is more informative if you bother to check collaterals. Femoral arterial lines are larger, better in profound shock, and risk retroperitoneal hemorrhage. Brachial lines sit near the median nerve and have weaker collateral options — use them only when radial and femoral are impossible. Axillary and dorsalis pedis are reserve sites.
Transduce at the phlebostatic axis (mid-chest). For CPP you care about the same transducer height you use for MAP. Zero to atmosphere. A damped tracing is a clot, a bubble, or a wrist that is bent — not a reason to believe the cuff over a correctly leveled arterial line without troubleshooting.
Ultrasound habits that prevent catastrophe
Dynamic needle-in-plane or out-of-plane visualization of the tip , not just the shaft.
Distinguish artery from vein: pulsatility, non-compressibility, Doppler.
After CVC placement, lung ultrasound for sliding before you wait on a chest radiograph if the patient desaturates.
After radial cannulation, check distal color, Doppler, and pain — early ischemia means the catheter comes out.
Lung ultrasound: A-lines, B-lines, and the lung point
A high-frequency linear probe is excellent for sliding and pneumothorax at the anterior chest; a curvilinear or phased-array probe sees effusions and B-lines. Place the probe in sagittal intercostal spaces so you see two ribs and the pleural line between them.
Lung sliding is the to-and-fro shimmer of visceral against parietal pleura. On M-mode, sliding is the seashore sign (sandy lung under a still chest wall). Absent sliding produces the stratosphere / barcode sign. Absent sliding is not diagnostic of pneumothorax by itself: mainstem intubation, apnea (including during a BD/DNC apnea test), dense adhesions, and bullous disease also kill sliding.
A-lines are horizontal reverberation artifacts repeating below the pleural line at multiples of the probe-to-pleura distance. Prominent A-lines with preserved sliding mean aerated lung (normal, pulmonary embolism, or asthma/COPD). A-lines without sliding raise pneumothorax on the differential at that spot.
B-lines are vertical laser-like reverberations that erase A-lines, move with sliding, and reach the bottom of the screen. One or two in a space can be normal. Three or more B-lines in a rib space, in several spaces, define an interstitial syndrome : pulmonary edema, ARDS, pneumonia, or fibrosis. Neurogenic pulmonary edema after SAH or a seizure is a B-line diagnosis at the bedside while you wait for a chest radiograph.
Lung point is the moment the probe sees sliding (or B-lines) on one side of the image and absent sliding / barcode on the other, in the same rib space, moving with respiration. That transition is specific for pneumothorax . It maps the edge of the pleural air. A complete, large pneumothorax may have no lung point anteriorly because the lung is collapsed posteriorly — then you combine absent sliding, absent B-lines, A-lines, and the clinical story (subclavian attempt, positive-pressure ventilation, sudden desaturation).
Pleural effusion is anechoic (or complex) fluid above the diaphragm with a positive spine sign and, on M-mode, a sinusoid sign of the lung moving in fluid. Hemothorax looks similar but may be particulate. After a difficult subclavian line, look at both the anterior chest for pneumothorax and the flanks for new fluid.
The BLUE protocol mindset (Bedside Lung Ultrasound in Emergency) still helps shock and respiratory failure: venous compression for DVT, anterior A/B profiles, and posterolateral effusion. You do not need to recite every BLUE profile name on this examination, but you do need to know that A-profile plus DVT points toward embolism, and that an anterior B-profile is edema until proven otherwise.
- Finding Meaning Neuro-ICU use
- Sliding + A-lines Aerated lung Argues against pneumothorax at that site
- Sliding + ≥3 B-lines Interstitial syndrome Neurogenic edema, aspiration, volume overload
- No sliding, A-lines, lung point Pneumothorax Post-CVC, post-barostress
No sliding, no lung point PTX or apnea, mainstem, adhesions Do not needle the chest on barcode alone during apnea testing
- Anechoic dependent collection Effusion / hemothorax After attempted subclavian or chest trauma
- Thoracic echo: tamponade, ventricles, IVC
A bedside transthoracic study in subxiphoid, parasternal long- and short-axis, and apical windows answers four shock questions: Is there pericardial tamponade ? Is the LV empty, hyperdynamic, or severely hypokinetic (including neurogenic stunned myocardium / takotsubo after SAH)? Is the RV dilated and strained (massive PE, hypoxia, high PEEP)? Is the IVC plethoric or collapsing?
Tamponade is a clinical diagnosis that echo supports: pericardial effusion plus right atrial systolic collapse , right ventricular diastolic collapse , a plethoric IVC that does not collapse, and exaggerated inspiratory variation of mitral/tricuspid inflows. After CVC placement, a new effusion and obstructive shock is wire or dilator injury until proven otherwise — that is a crash thoracotomy / pericardial drain conversation, not a fluid bolus. Loculated postoperative hematoma can tamponade without a circumferential black stripe.
LV qualitative function is enough for most ICU decisions: squeeze is hyperdynamic in vasoplegia and hypovolemia, globally poor after anoxic injury or myocarditis, and regionally abnormal in infarction. After aneurysmal SAH, an apical ballooning pattern with modest troponin and no culprit lesion is neurocardiogenic , not an automatic trip to the catheterization laboratory — but ST elevation still needs an ECG-first approach.
RV dilation with septal flattening ( D-sign ) in systole suggests pressure overload. McConnell’s sign (apex-sparing RV free-wall hypokinesis) is a PE clue, not pathognomonic. Do not load a failing RV with liters of crystalloid because “the IVC looks small in one clip.”
IVC diameter and inspiratory collapse estimate right atrial pressure in spontaneously breathing patients. In positive-pressure ventilation , collapse is less trustworthy; a fat, non-varying IVC more reliably says high RA pressure (tamponade, RV failure, high PEEP, fluid overload) than a thin IVC proves “give 2 liters.” Integrate with the rest of the echo and the blood pressure.
Complications to name without hedging
Procedure Complication First response
IJ CVC Carotid puncture, airway hematoma, IJ thrombosis raising ICP Hold pressure; do not dilate an artery; ultrasound the neck; ICP-directed care if venous outflow is blocked
Subclavian CVC Pneumothorax, hemothorax Lung ultrasound; chest tube if needed; never both subclavians blindly in one sitting
Femoral CVC Infection, DVT, arterial puncture Remove infected lines; anticoagulation decisions vs hematoma
Any CVC Catheter-related bloodstream infection; wire embolism; atrial perforation / tamponade Sterile technique; never let go of the wire; echo for new shock
Arterial line Distal ischemia, pseudoaneurysm, accidental intra-arterial injection Remove the catheter; vascular surgery if the hand is cold
Lung ultrasound false call Needling a barcode that was apnea or mainstem intubation Confirm lung point or clinical PTX before decompression
Worked scenarios
A patient with a left hemispheric mass and ICP 32 mm Hg needs vasopressors. A right IJ dialysis catheter already occupies the remaining jugular. Place a femoral or subclavian CVC rather than a second IJ.
Desaturation 10 minutes after a left subclavian attempt: anterior left chest shows A-lines without sliding and a lung point — treat as pneumothorax. The same barcode during apnea testing without a lung point may simply be a disconnected ventilator.
PEA after a difficult wire: subxiphoid echo with a new pericardial stripe and RV diastolic collapse is tamponade from injury, not “anesthetic vasodilation.”
Exam traps
Bilateral IJ catheters in a high-ICP patient. Dilating a pulsatile vessel because the ultrasound picture was pretty. Calling absent sliding during BD/DNC apnea a pneumothorax without a lung point. Using EEG language in this procedures section. Treating a small collapsing IVC on high PEEP as a license for uncontrolled volume in a herniating patient. Forgetting that TCD in the previous section is a cerebral blood-flow ancillary test, while here TTE is a shock and tamponade tool.