Critical Care Prophylaxis, Nutrition & Infection Prevention

ABPN Neurocritical Care Study Guide Exam

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1 Chapter 1: Neurologic Examination & Coma Assessment in the ICU

Current Examination, Blueprint & Preparation Neurologic Examination in Critically Ill Patients Coma Evaluation & Consciousness Alterations Delirium & Toxic-Metabolic Encephalopathy in the ICU

2 Chapter 2: Cerebral Physiology & Intracranial Dynamics

Cerebral Blood Flow, Metabolism & Autoregulation Intracranial Pressure & Compliance Cerebral Edema & Herniation Syndromes

3 Chapter 3: Intracranial Hypertension & Cerebral Perfusion Management

Tiered ICP Management Protocols Hyperosmolar Therapy & Fluid Management Advanced & Refractory ICP Interventions

4 Chapter 4: Airway, Mechanical Ventilation & Pulmonary ICU Management

Emergency Airway Management & Neuro-Intubation Mechanical Ventilation Strategies in Acute Brain Injury Tracheostomy & Ventilator Weaning in Neurocritical Care Pulmonary Complications in the Neuro-ICU Obstructive Lung Disease, Pulmonary Hypertension & Bronchoscopy

5 Chapter 5: Hemodynamics, Shock & Cardiovascular Management

Hemodynamic Monitoring & Blood Pressure Targets Vasoactive Agents: Inotropes, Vasopressors & Antihypertensives Cardiac Complications of Brain Injury

6 Chapter 6: Neuropharmacology, Analgesia & Sedation

ICU Sedation & Analgesia Neuromuscular Blockade & Monitoring Propofol Infusion Syndrome & Drug Toxicities Antiseizure Drug Pharmacology in the ICU

7 Bleeding, Thrombosis & Hematologic Emergencies

Warfarin & Heparin Reversal Direct Oral Anticoagulant (DOAC) Reversal Antiplatelet Management & Platelet Dysfunction Venous Thromboembolism Prophylaxis & Management Transfusion, Coagulopathy, TMA & Cellular-Therapy Neurotoxicity

8 Chapter 8: Systemic ICU Care, Fluids, Electrolytes & Endocrine

Hyponatremia & Osmoregulation: SIADH vs Cerebral Salt Wasting Diabetes Insipidus, Hypernatremia & Endocrine Crises Critical Care Prophylaxis, Nutrition & Infection Prevention

9 Systemic Trauma & Environmental Injury

Polytrauma, Chest Injury & Abdominal Hemorrhage Burns, Electrical Injury & Hanging

10 Cardiac Emergencies & Mechanical Support

IABP, Ventricular Devices & ECMO Acute Coronary, Valvular, Rhythm & Aortic Emergencies

11 Kidney Injury, Acid–Base & Renal Replacement

Acute Kidney Injury & Renal Drug Clearance Acid–Base Disorders, Electrolytes & Renal Replacement

12 Systemic Infection & Endocrine Emergencies

Sepsis, Endocarditis & Antimicrobial Principles Thyroid, Adrenal & Dysglycemic Emergencies

13 Gastrointestinal & Hepatic Emergencies

Acute Abdomen, GI Bleeding & Abdominal Compartment Syndrome Acute Liver Failure, Cirrhosis & Hepatic Drug Effects

14 Chapter 9: Neuroimaging in the Neuro-ICU

Non-Contrast CT & CT Angiography CT Perfusion & Advanced Perfusion Imaging Magnetic Resonance Imaging in Critical Illness

15 Chapter 10: Electrophysiology & Neuromonitoring

Continuous EEG & ACNS Standardized Critical Care Terminology Invasive Neuromonitoring: ICP & External Ventricular Drains Multimodal Monitoring: PbtO2, Microdialysis & Transcranial Doppler

16 Angiography, Electrodiagnosis & CSF Analysis

Conventional Angiography & Cranial–Spinal Shunts EMG, Nerve Conduction & Acute Muscle Disease CSF Analysis: Infection, Inflammation & Hemorrhage

17 Chapter 11: Bedside Procedures, Ultrasound & Death by Neurologic Criteria

Critical Care Procedural Skills Critical Care Ultrasound & Echocardiography Determination of Death by Neurologic Criteria

18 Chapter 12: Acute Ischemic Stroke & Reperfusion Therapies

Acute Ischemic Stroke Management & Thrombolysis Endovascular Thrombectomy & Large Vessel Occlusion Malignant Hemispheric & Cerebellar Infarction

19 Chapter 13: Spontaneous Intracerebral Hemorrhage & Intraventricular Hemorrhage

Acute Intraparenchymal Hemorrhage Management Intraventricular Hemorrhage & Hydrocephalus Surgical Evacuation & Minimally Invasive Surgery in ICH

20 Chapter 14: Aneurysmal Subarachnoid Hemorrhage & Delayed Cerebral Ischemia

Aneurysmal Subarachnoid Hemorrhage: Acute Resuscitation & Securing Delayed Cerebral Ischemia & Cerebral Vasospasm Non-Aneurysmal Subarachnoid Hemorrhage & Vascular Malformations

21 Venous, Spinal & Traumatic Vascular Disease

Cerebral Venous Thrombosis & Spinal Cord Infarction Traumatic Dissection, Carotid–Cavernous Fistula & Penetrating Injury

22 Chapter 15: Traumatic Brain & Spinal Cord Injury

Severe Traumatic Brain Injury & Contusions Acute Traumatic Spinal Cord Injury & Neurogenic Shock Spine Trauma, Fractures & Cord Syndromes

23 Chapter 16: Status Epilepticus, Seizures & Neuromuscular Emergencies

Status Epilepticus: Convulsive & Non-Convulsive Refractory & Super-Refractory Status Epilepticus Acute Neuromuscular Respiratory Failure

24 Chapter 17: Post-Cardiac Arrest Care, CNS Infections & Encephalitis

Targeted Temperature Management & Post-Cardiac Arrest Care Post-Cardiac Arrest Neuroprognostication Acute CNS Infections, Encephalitis & Inflammatory Emergencies

25 Neuroinflammation & Neurooncology

Fulminant Demyelination & Autoimmune Encephalitis Brain, Spinal & Leptomeningeal Cancer Emergencies

26 Pregnancy, Transplantation & Pediatric Care

Pregnancy, Postpartum & Post-Transplant Neurologic Care Pediatric Neurocritical Care

27 Chapter 18: Neurosurgical & Perioperative Emergencies

Postoperative Neurosurgical Complications Device Complications: EVDs, Shunts & ICP Monitors Cerebral Hyperperfusion Syndrome & Post-Interventional Emergencies

28 Chapter 19: Ethics, Palliative Care & Organ Donation in the Neuro-ICU

Communication, Surrogate Decision-Making & Conflict Resolution Neuroprognostication Ethics, Withdrawal of Life Support & Palliative Care Organ Donation & Management of the Deceased Donor

Critical Care Prophylaxis, Nutrition & Infection Prevention

Key Takeaways Explain This Topic AI

Stress-ulcer prophylaxis depends on bleeding risk; the 2024 guideline recognizes shock, coagulopathy, and chronic liver disease rather than ventilation alone as a firm independent risk.

Avoid severe hyperglycemia and hypoglycemia; intensive insulin targets increased harm in NICE-SUGAR.

Begin and advance enteral support when appropriate to perfusion and gut function, with individualized energy, protein, and refeeding assessment.

Use insertion and maintenance bundles, closed drainage, and daily necessity review for invasive lines and urinary catheters.

Prevent skin and device pressure injury and advance mobility when safe; neuropathic pain treatment requires organ and sedation-risk assessment.

Last updated: October 2026

Critical Care Prophylaxis, Nutrition & Infection Prevention

Optimizing outcomes in neurocritical care requires rigorous systemic intensive care support that runs parallel to primary neurosurgical and neuromedical therapies. Neurologically critically ill patients are uniquely vulnerable to systemic complications—including stress-induced mucosal ulceration, secondary ischemic brain injury from glycemic volatility, hypercatabolic malnutrition, and device-associated hospital-acquired infections. A disciplined, evidence-based approach to prophylaxis, metabolic support, and infection prevention is essential to mitigate secondary brain injury and systemic organ dysfunction.

• Stress Ulcer Prophylaxis (SUP) in Neurocritical Care
• Pathophysiology of Stress-Related Mucosal Disease (SRMD)

Critically ill patients experience visceral hypoperfusion secondary to sympathetic overactivation, splanchnic vasoconstriction, systemic hypotension, and hypovolemia. Decreased gastric mucosal blood flow impairs microvascular bicarbonate delivery, depletes mucus production, and disrupts the epithelial tight junctions, allowing luminal gastric acid ( H C l HCl H Cl ) and pepsin to erode the mucosa.

In neurocritical care, patients are additionally predisposed to Cushing ulcers —distinctive, deep, and perforating peptic ulcers occurring in the setting of severe intracranial hypertension, traumatic brain injury, or brainstem injury. Increased intracranial pressure stimulates hypothalamic autonomic centers and the vagal motor nucleus, causing excessive parasympathetic vagal discharge. Hyperstimulation of postganglionic muscarinic ( M 1 M_1 M 1 ​ and M 3 M_3 M 3 ​ ) receptors on gastric parietal cells triggers massive, unchecked hydrochloric acid secretion through the H + / K + H^+/K^+ H + / K + ATPase pump.

Evidence-Based Indications for SUP

The 2024 SCCM/ASHP guideline identifies coagulopathy, shock, and chronic liver disease as likely important risk factors. It does not find firm evidence that mechanical ventilation alone is an independent risk factor. Consider the full bleeding risk, including the neurologic context, rather than automatically treating every intubation as a definite indication.

Use a low-dose PPI or H2 blocker when prophylaxis is indicated, and stop when the relevant risk has resolved. Enteral nutrition can reduce risk but does not necessarily replace prophylaxis in a patient with significant risk factors. Prior bleeding, treatment exposure, and clinical circumstances may affect individual decisions. Prophylaxis is distinct from treatment of established GI hemorrhage.

Pharmacologic Comparison: PPIs vs. H 2 H_2 H 2 ​ RAs

Feature Histamine-2 Receptor Antagonists ( H 2 H_2 H 2 ​ RA, e.g., Famotidine) Proton Pump Inhibitors (PPI, e.g., Pantoprazole)

Mechanism Reversible, competitive antagonism of H 2 H_2 H 2 ​ receptors on parietal cells Irreversible covalent inhibition of active parietal H + / K + H^+/K^+ H + / K + ATPase pumps

Acid Suppression Moderate suppression; subject to tachyphylaxis/tolerance within 48–72 hours Profound, sustained suppression ; no tachyphylaxis

Bleeding Reduction Significantly reduces clinically important GI bleeding Slightly lower overt bleeding rates in high-risk patients compared to H 2 H_2 H 2 ​ RAs

Infection considerations Assess individual risk Observational associations do not establish that PPIs inevitably cause excess infection; randomized data and current guidance inform selection

Drug Interactions Minimal (famotidine); requires renal dose reduction Variable CYP2C19 inhibition (minimal with pantoprazole)

Bone / Renal Risks Minimal Associated with hypomagnesemia, acute interstitial nephritis

Note

Clinical practice in neurocritical care increasingly balances bleeding prevention against infectious risks. For most patients meeting SUP criteria, famotidine ( 20 mg 20\text{ mg} 20 mg IV/PO q12h, adjusted for renal clearance) or pantoprazole ( 40 mg 40\text{ mg} 40 mg IV/PO daily) are acceptable first-line agents. SUP should be promptly deprescribed once the patient is successfully extubated, coagulopathy has resolved, and enteral nutrition is established.

• Glycemic Control in Acute Brain Injury
• Neurotoxic Mechanisms of Hyperglycemia

Stress hyperglycemia is triggered by excessive sympathoadrenal discharge, endogenous cortisol release, glucagon secretion, and systemic insulin resistance. In acute brain injury (ischemic stroke, ICH, aSAH, and TBI), serum glucose > 180 mg/dL > 180\text{ mg/dL} > 180 mg/dL produces pronounced secondary neurotoxicity:

Lactic Acidosis: Hyperglycemia accelerates anaerobic glucose metabolism within ischemic tissue, generating marked intracellular lactic acidosis and tissue acidosis that destabilizes mitochondrial membranes.

Reactive Oxygen Species ( R O S ROS ROS ): Excessive glucose influx drives mitochondrial electron transport chain overload, generating superoxide radicals, peroxynitrite, and oxidative lipid peroxidation.

Blood-Brain Barrier Breakdown: Hyperglycemia upregulates matrix metalloproteinase-9 ( M M P − 9 MMP-9 MMP − 9 ), digesting vascular endothelial basement membranes and precipitating vasogenic edema and hemorrhagic transformation.

The NICE-SUGAR Trial & Contemporary Targets

Historically, the 2001 Leuven trial suggested that "tight" glycemic control ( 80 – 110 mg/dL 80\text{--}110\text{ mg/dL} 80 – 110 mg/dL ) dramatically reduced critical illness mortality. However, the landmark NICE-SUGAR trial (2009; 6,104 patients) definitively refuted this hypothesis:

Intensive insulin therapy ( 80 – 110 mg/dL 80\text{--}110\text{ mg/dL} 80 – 110 mg/dL ) produced a increase in severe hypoglycemia ( < 40 mg/dL < 40\text{ mg/dL} < 40 mg/dL ; 6.8 % 6.8\% 6.8% vs 0.5 % 0.5\% 0.5% ).

Intensive therapy resulted in a significant increase in 90-day all-cause mortality ( 27.5 % 27.5\% 27.5% vs 24.9 % 24.9\% 24.9% ; Odds Ratio 1.14 1.14 1.14 ).

Neuroglycopenia in the Neuro-ICU

Cerebral microdialysis studies demonstrate that the injured brain is exceptionally vulnerable to systemic glucose drops. Lowering systemic glucose to < 100 mg/dL < 100\text{ mg/dL} < 100 mg/dL frequently produces cerebral neuroglycopenia (brain interstitial glucose < 0.8 mmol/L < 0.8\text{ mmol/L} < 0.8 mmol/L ) and cellular energy crisis (lactate-to-pyruvate ratio L P R > 40 LPR > 40 L PR > 40 ), triggering irreversible secondary neuronal necrosis even when systemic blood glucose remains technically "normal."

Important

Neurocritical Care Glycemic Recommendations:

Moderate Glycemic Target: Maintain blood glucose between 140 – 180 mg/dL 140\text{--}180\text{ mg/dL} 140 – 180 mg/dL ( 7.8 – 10.0 mmol/L 7.8\text{--}10.0\text{ mmol/L} 7.8 – 10.0 mmol/L ). Initiate a continuous intravenous regular insulin infusion when blood glucose persistently exceeds 180 mg/dL 180\text{ mg/dL} 180 mg/dL .

Strict Avoidance of Hypoglycemia: Absolute blood glucose < 70 mg/dL < 70\text{ mg/dL} < 70 mg/dL must be aggressively avoided and treated immediately with 50 % 50\% 50% dextrose ( D 50 W D_{50}W D 50 ​ W ), because severe neuroglycopenia can cause seizures and brain injury; choose the dextrose concentration and route according to protocol and access.

• Enteral Nutrition Support & Metabolic Demands
• Hypermetabolism and Hypercatabolism in Brain Injury

Severe acute brain injury induces a profound systemic hypermetabolic state. In severe TBI and status epilepticus, the hyperadrenergic state can increase energy expenditure, with considerable patient-to-patient variation. Protein breakdown accelerates, resulting in massive urinary nitrogen loss ( > 20 – 30 g/day > 20\text{--}30\text{ g/day} > 20 – 30 g/day ) and rapid depletion of somatic lean muscle mass.

Timing & Route of Nutritional Support

Early Enteral Nutrition (EEN): Enteral feeding should be initiated within 24 to 48 hours 24\text{ to }48\text{ hours} 24 to 48 hours of neuro-ICU admission once hemodynamic resuscitation is complete.

Physiologic Benefits: Luminal nutrients stimulate gut mucosal blood flow, maintain intestinal epithelial tight junctions, stimulate secretory I g A IgA I g A production, and prevent bacterial translocation through the gut barrier, significantly reducing systemic sepsis and ventilator-associated pneumonia.

Enteral vs. Parenteral: Enteral nutrition ( E N EN EN ) is strongly preferred over total parenteral nutrition ( T P N TPN TPN ). Parenteral support is selected when enteral feeding is contraindicated or persistently insufficient, with timing based on nutritional risk and clinical guidance.

Energy and protein: Prefer measured expenditure when available and advance support according to illness phase, tolerance, nutritional risk, and local guidance rather than delivering a fixed full 25–30 kcal/kg immediately to every unstable patient. Protein needs are individualized. Screen for refeeding risk; replace thiamine and relevant electrolytes and monitor phosphate, potassium, magnesium, glucose, and fluid balance while advancing nutrition.

Gastric Residual Volumes (GRVs) & Post-Pyloric Feeding

Routine cessation of enteral nutrition for moderate gastric residual volumes ( G R V < 250 – 500 mL GRV < 250\text{--}500\text{ mL} GR V < 250 – 500 mL ) is no longer recommended, as it causes severe nutritional deficits without reducing aspiration pneumonia.

If gastroparesis or persistent intolerance occurs, administer prokinetic agents (metoclopramide 10 mg 10\text{ mg} 10 mg IV q6h or low-dose erythromycin 125 – 250 mg 125\text{--}250\text{ mg} 125 – 250 mg IV q8h).

If high aspiration risk or intolerance persists, place a post-pyloric (nasoduodenal or nasojejunal) feeding tube .

ICU-Acquired Infection Prevention: Device Bundles

Critically ill neurologic patients frequently require invasive intravascular lines and indwelling urinary catheters, placing them at high risk for hospital-acquired bacteremia and urosepsis.

Central Line-Associated Bloodstream Infection (CLABSI) Bundle

Strict adherence to the evidence-based CLABSI bundle dramatically reduces catheter infections:

Hand Hygiene: Thorough hand washing or alcohol-based rub prior to catheter insertion and manipulation.

Maximal Sterile Barrier Precautions: The operator must wear cap, mask, sterile gown, and sterile gloves; the patient is covered with a full-body sterile drape.

Chlorhexidine Skin Antisepsis: Prepare insertion site with > 0.5 % > 0.5\% > 0.5% chlorhexidine gluconate in 70 % 70\% 70% isopropyl alcohol; allow to dry completely according to the product instructions.

Optimal Site Selection: Avoid femoral vein catheterization in adult patients due to high rates of thrombosis and bacterial colonization. The subclavian site carries the lowest infection risk, followed by the internal jugular vein.

Daily Review and Prompt Removal: Daily assessment of catheter necessity with immediate removal of unneeded lines is the important component of the CLABSI prevention bundle.

Catheter-Associated Urinary Tract Infection (CAUTI) Bundle

Indwelling urinary catheters are a leading source of secondary bacteremia and septic shock in the ICU:

Restrict Indications: Place urinary catheters strictly for objective indications: acute urinary retention, hourly urine output titration in hemodynamic shock or active intracranial pressure resuscitation, and selected open sacral/perineal wounds in an incontinent patient when the benefits justify the catheter risk.

Aseptic Insertion: Use sterile equipment, sterile gloves, and sterile drape during placement.

Closed Drainage System: Maintain an uninterrupted, sterile closed drainage circuit; never disconnect catheter and tubing.

Unobstructed Downward Flow: Keep collection bag continuously below the level of the bladder; avoid tubing kinks or loops.

Early Catheter Removal: Reassess need during daily multidisciplinary rounds. Implement nurse-driven Foley removal protocols once hourly titration is no longer required.

Skin Protection, Mobility, and Pain

Inspect pressure-prone skin, use an appropriate support surface, offload heels, and reposition according to tolerance while protecting the airway, spine, drains, and perfusion. Device-related pressure injury can occur under collars, tubing, masks, and splints; skin checks must include these areas. An unstable spine or active ICP crisis changes the mobilization plan rather than eliminating reassessment forever. Begin a coordinated progression from passive activity to sitting, standing, and walking when physiologically safe, with nursing, therapy, and the clinical team.

Neuropathic pain after cord injury or other neural damage can involve burning, electric, or stimulus-evoked pain that responds differently from incisional nociception. Gabapentin or pregabalin may be useful, but require renal adjustment and monitoring for sedation and respiratory effects, especially with opioids. Other agents, such as selected antidepressants, need attention to blood pressure, anticholinergic effects, arrhythmia, serotonin interactions, and the neurologic examination. Combine medication with positioning, rehabilitation, and treatment of the underlying cause. Do not use paralysis to mask pain or agitation.