Skip to content

Critical Illness Myopathy/Neuropathy (ICU-Acquired Weakness)

VERSION: 1.1 CREATED: January 30, 2026 REVISED: January 30, 2026 STATUS: Approved


DIAGNOSIS: Critical Illness Myopathy/Neuropathy (ICU-Acquired Weakness)

ICD-10: G72.81 (Critical illness myopathy), G62.81 (Critical illness polyneuropathy), M62.81 (ICU-acquired weakness)

CPT CODES: 85025 (CBC with differential), 80053 (CMP (BMP + LFTs)), 83735 (Magnesium), 84100 (Phosphorus), 82330 (Calcium (ionized)), 82550 (Creatine kinase (CK)), 82947 (Blood glucose), 82803 (Arterial blood gas (ABG)), 83605 (Lactate), 84145 (Procalcitonin), 84443 (TSH), 81003 (Urinalysis with microscopy), 82085 (Aldolase), 83615 (LDH), 83874 (Myoglobin (serum)), 86255 (Anti-ganglioside antibodies (GM1, GD1a, GQ1b)), 86235 (Acetylcholine receptor antibodies), 82533 (Cortisol (random or AM)), 84439 (Free T4), 82306 (Vitamin D (25-OH)), 84134 (Prealbumin), 83036 (HbA1c), 83018 (Heavy metals (lead, arsenic, thallium)), 84120 (Porphyrins (urine ALA, PBG)), 20200 (Muscle biopsy), 64795 (Nerve biopsy (sural)), 95907-95913 (Nerve conduction studies (NCS)), 71046 (Chest X-ray), 93000 (ECG (12-lead)), 76604 (Ultrasound: diaphragm), 76881 (Ultrasound: muscle (quadriceps, biceps)), 72156 (MRI spine (whole) with and without contrast), 70553 (MRI brain with and without contrast), 94010 (Pulmonary function testing (formal spirometry)), 71260 (CT chest with contrast), 73718 (MRI muscle (thigh or upper arm)), 76000 (Fluoroscopic sniff test), 95907 (Phrenic nerve conduction study)

SYNONYMS: ICU-acquired weakness, ICUAW, critical illness myopathy, CIM, critical illness polyneuropathy, CIP, critical illness neuromyopathy, CINM, intensive care unit acquired paresis, acute quadriplegic myopathy, thick filament myopathy, critical care myopathy, critical care polyneuropathy, ventilator-associated weakness

SCOPE: Diagnosis, management, and rehabilitation of ICU-acquired weakness (ICUAW) including critical illness myopathy (CIM), critical illness polyneuropathy (CIP), and combined CIM/CIP (CINM). Covers risk factor identification and modification, electrodiagnostic differentiation (NCS/EMG including direct muscle stimulation), MRC sum score assessment, supportive management, early mobilization, ventilator liberation strategies, nutritional optimization, and long-term prognosis. Excludes pre-existing neuromuscular disorders (GBS, myasthenia gravis, ALS), spinal cord injury, and prolonged neuromuscular blockade effect without underlying neuromyopathy.


PRIORITY KEY: STAT = Immediate | URGENT = Within hours | ROUTINE = Standard | EXT = Extended/atypical cases | - = Not applicable to this setting

═══════════════════════════════════════════════════════════════ SECTION A: ACTION ITEMS ═══════════════════════════════════════════════════════════════

1. LABORATORY WORKUP

1A. Essential/Core Labs

Test Rationale Target Finding ED HOSP OPD ICU
CBC with differential (CPT 85025) Baseline; infection screen; leukocytosis suggests ongoing sepsis as risk factor for ICUAW Normal; leukocytosis or bandemia suggest active infection STAT STAT ROUTINE STAT
CMP (BMP + LFTs) (CPT 80053) Electrolytes (K, Mg, Ca, Phos affect muscle function); renal/hepatic function; glucose control assessment Normal; hyperglycemia >180 mg/dL requires insulin adjustment; electrolyte correction STAT STAT ROUTINE STAT
Magnesium (CPT 83735) Hypomagnesemia worsens weakness and impairs neuromuscular transmission >2.0 mg/dL; replete if low STAT STAT ROUTINE STAT
Phosphorus (CPT 84100) Hypophosphatemia causes profound muscle weakness including respiratory muscles; may mimic or worsen ICUAW >2.5 mg/dL; replete aggressively if <1.5 mg/dL STAT STAT ROUTINE STAT
Calcium (ionized) (CPT 82330) Hypocalcemia increases neuromuscular excitability; hypercalcemia causes weakness Normal ionized Ca 4.5-5.3 mg/dL STAT STAT ROUTINE STAT
Creatine kinase (CK) (CPT 82550) Elevated in CIM (often moderately 1000-5000 IU/L); very high levels suggest rhabdomyolysis; normal in CIP Mildly to moderately elevated in CIM; normal in CIP; >10,000 suggests rhabdomyolysis STAT STAT ROUTINE STAT
Blood glucose (CPT 82947) Hyperglycemia is a major modifiable risk factor for ICUAW; target 140-180 mg/dL per NICE-SUGAR 140-180 mg/dL; avoid hypoglycemia <70 mg/dL STAT STAT ROUTINE STAT
Arterial blood gas (ABG) (CPT 82803) Assess ventilation (PaCO2) and oxygenation; hypercapnia indicates respiratory muscle weakness contributing to ventilator dependence Normal: pH 7.35-7.45, PaCO2 35-45; rising PaCO2 suggests respiratory muscle failure STAT STAT - STAT
Lactate (CPT 83605) Elevated in sepsis and tissue hypoperfusion; ongoing sepsis perpetuates ICUAW <2.0 mmol/L STAT STAT - STAT
Procalcitonin (CPT 84145) Distinguish ongoing infection from inflammatory state; persistent sepsis worsens ICUAW prognosis <0.5 ng/mL; elevated suggests active infection requiring treatment STAT STAT - STAT
TSH (CPT 84443) Hypothyroid myopathy can mimic CIM; critical illness may cause sick euthyroid syndrome Normal (interpret cautiously in ICU setting) - ROUTINE ROUTINE ROUTINE
Urinalysis with microscopy (CPT 81003) UTI as source of ongoing sepsis; myoglobinuria if rhabdomyolysis Negative; dark urine may indicate myoglobinuria STAT ROUTINE ROUTINE STAT

1B. Extended Workup (Second-line)

Test Rationale Target Finding ED HOSP OPD ICU
Aldolase (CPT 82085) Muscle injury marker; may be elevated in CIM alongside CK; supports myopathic process Elevated in CIM; normal in CIP - ROUTINE ROUTINE ROUTINE
LDH (CPT 83615) Non-specific marker of tissue damage; elevated in myopathy and hemolysis Elevated in CIM - ROUTINE ROUTINE ROUTINE
Myoglobin (serum) (CPT 83874) Muscle breakdown marker; elevated in CIM and rhabdomyolysis; renal toxicity risk <90 ng/mL; elevated suggests muscle damage - ROUTINE - URGENT
Urine myoglobin (CPT 83874) Myoglobinuria from muscle breakdown; renal injury risk Negative; positive indicates significant muscle damage - ROUTINE - URGENT
Anti-ganglioside antibodies (GM1, GD1a, GQ1b) (CPT 86255) Exclude GBS if clinical presentation unclear; GBS can develop during ICU stay Negative; positive suggests GBS rather than ICUAW - ROUTINE ROUTINE ROUTINE
Acetylcholine receptor antibodies (CPT 86235) Exclude myasthenia gravis if weakness pattern suggests NMJ disorder Negative; positive suggests MG - ROUTINE ROUTINE ROUTINE
Anti-MuSK antibodies (CPT 86235) Exclude MuSK-positive myasthenia if AChR negative but MG suspected Negative - ROUTINE ROUTINE -
Cortisol (random or AM) (CPT 82533) Adrenal insufficiency from prolonged steroid use causing weakness; critical illness-related corticosteroid insufficiency AM cortisol >10 mcg/dL generally adequate; <10 suggests insufficiency - ROUTINE - ROUTINE
Free T4 (CPT 84439) Hypothyroid myopathy in differential; thyroid dysfunction assessment Normal - ROUTINE ROUTINE ROUTINE
Vitamin D (25-OH) (CPT 82306) Deficiency is common in ICU patients and contributes to muscle weakness and impaired recovery >30 ng/mL; supplement if <20 ng/mL - ROUTINE ROUTINE ROUTINE
Prealbumin (CPT 84134) Nutritional status marker; low levels indicate protein malnutrition affecting muscle recovery >15 mg/dL; low suggests inadequate nutrition - ROUTINE ROUTINE ROUTINE
HbA1c (CPT 83036) Chronic glycemic control assessment; poorly controlled diabetes increases ICUAW risk <7% in general; assess baseline diabetes control - ROUTINE ROUTINE ROUTINE

1C. Rare/Specialized (Refractory or Atypical)

Test Rationale Target Finding ED HOSP OPD ICU
Paraneoplastic antibody panel (CPT 86255) Paraneoplastic neuromyopathy in differential if cancer history or atypical features Negative - EXT EXT EXT
Anti-VGCC antibodies Lambert-Eaton myasthenic syndrome (LEMS) in differential; associated with small cell lung cancer Negative; positive = LEMS - EXT EXT -
Myositis-specific antibodies (Jo-1, Mi-2, SRP, MDA5) Inflammatory myopathy in differential if CK markedly elevated and atypical course Negative - EXT EXT -
Heavy metals (lead, arsenic, thallium) (CPT 83018) Toxic neuropathy mimic; occupational or environmental exposure Normal - EXT EXT -
Porphyrins (urine ALA, PBG) (CPT 84120) Acute intermittent porphyria mimic (motor neuropathy, autonomic dysfunction) Normal - EXT EXT -
Muscle biopsy (CPT 20200) Definitive differentiation CIM vs CIP when electrodiagnostics are inconclusive; shows thick filament (myosin) loss in CIM; rarely needed in practice CIM: selective loss of thick (myosin) filaments, type 2 fiber atrophy, necrosis; CIP: denervation changes, grouped atrophy - EXT EXT EXT
Nerve biopsy (sural) (CPT 64795) Rarely indicated; axonal degeneration in CIP; only when diagnosis is uncertain and alternative treatable diagnoses are considered CIP: axonal degeneration of sensory and motor fibers; no inflammation - EXT EXT -

2. DIAGNOSTIC IMAGING & STUDIES

2A. Essential/First-line

Study Timing Target Finding Contraindications ED HOSP OPD ICU
Nerve conduction studies (NCS) (CPT 95907-95913) / EMG (CPT 95886) When ICUAW suspected (typically after 1 week ICU stay with new weakness); ideally after sedation lightened to allow cooperation CIP: reduced CMAP and SNAP amplitudes with normal conduction velocities (axonal pattern); CIM: reduced CMAP amplitudes with NORMAL SNAPs and myopathic MUP recruitment; Combined CINM: both axonal neuropathic and myopathic changes Anticoagulation (relative for needle EMG); unable to cooperate for volitional EMG - URGENT ROUTINE URGENT
Direct muscle stimulation (DMS) When CIM vs CIP differentiation needed in uncooperative or sedated patients; specialized technique CIM: reduced ratio of nerve-stimulated CMAP to direct muscle-stimulated CMAP (nerve:muscle ratio <0.5); CIP: preserved ratio with reduced CMAPs on both Requires specialized equipment; not widely available - EXT - URGENT
Chest X-ray (CPT 71046) On recognition of ICUAW; baseline for ventilator weaning assessment Atelectasis, pleural effusion, diaphragm elevation (weakness), aspiration None significant STAT ROUTINE - STAT
ECG (12-lead) (CPT 93000) Baseline; electrolyte abnormalities may cause arrhythmia; autonomic dysfunction assessment Sinus rhythm; check for QTc prolongation, electrolyte-related changes None STAT ROUTINE - STAT
Ultrasound: diaphragm (CPT 76604) Assess diaphragm thickness and excursion; predicts ventilator weaning success; diaphragm atrophy develops within 48-72h of mechanical ventilation Diaphragm thickness >2mm; thickening fraction >30% during inspiration; excursion >10mm; decreased values suggest diaphragm atrophy and prolonged weaning None significant - ROUTINE - URGENT
Ultrasound: muscle (quadriceps, biceps) (CPT 76881) Quantify muscle wasting; serial measurements track progression; cross-sectional area decreases significantly within first week of ICU Reduced muscle thickness and cross-sectional area compared to admission baseline; echogenicity changes suggest myopathic process None significant - ROUTINE ROUTINE ROUTINE

2B. Extended

Study Timing Target Finding Contraindications ED HOSP OPD ICU
MRI spine (whole) with and without contrast (CPT 72156) If spinal cord pathology suspected (upper motor neuron signs, sensory level) Normal spinal cord; exclude compressive myelopathy, epidural abscess, infarction Pacemaker, metallic implants; patient stability for transport - URGENT ROUTINE URGENT
MRI brain with and without contrast (CPT 70553) If central cause of weakness suspected (stroke, brainstem lesion) Normal; exclude stroke, demyelination, structural lesion Same as MRI spine - URGENT ROUTINE URGENT
Repeat NCS/EMG (CPT 95907-95913) At 2-4 weeks if initial study inconclusive or to assess prognosis and track recovery Evolution of findings; persistent denervation predicts slower recovery; reinnervation signs suggest improvement Same as initial NCS/EMG - ROUTINE ROUTINE ROUTINE
Pulmonary function testing (formal spirometry) (CPT 94010) When patient can cooperate; assess respiratory muscle strength for weaning readiness; outpatient monitoring of recovery FVC, MIP, MEP values; FVC >15 mL/kg supports weaning; serial improvement documents recovery Patient cooperation required - ROUTINE ROUTINE ROUTINE
CT chest with contrast (CPT 71260) If pulmonary pathology suspected (PE, empyema) complicating weaning failure Pulmonary embolism; pleural effusion; lung pathology Contrast allergy; renal impairment - ROUTINE - URGENT

2C. Rare/Specialized

Study Timing Target Finding Contraindications ED HOSP OPD ICU
MRI muscle (thigh or upper arm) (CPT 73718) When inflammatory myopathy in differential; assesses muscle edema and fatty infiltration CIM: diffuse muscle edema on STIR; inflammatory myopathy: focal/multifocal edema and enhancement MRI-incompatible implants - EXT EXT -
Fluoroscopic sniff test (CPT 76000) Diaphragm paralysis evaluation when ultrasound is equivocal; paradoxical diaphragm motion Normal bilateral diaphragm excursion; paradoxical motion indicates paralysis Radiation exposure; patient must be transported - EXT EXT -
Phrenic nerve conduction study (CPT 95907) Assess phrenic nerve function directly; CIP may involve phrenic nerves causing diaphragm weakness Reduced phrenic CMAP amplitude suggests CIP involving phrenic nerve; normal suggests preserved phrenic function Same as standard NCS - EXT - EXT

3. TREATMENT

3A. Acute/Emergent

Treatment Route Indication Dosing Contraindications Monitoring ED HOSP OPD ICU
Insulin (regular) infusion IV Glycemic control to reduce ICUAW risk and severity; hyperglycemia is major modifiable risk factor Variable rate :: IV :: continuous :: Insulin infusion per ICU protocol; target glucose 140-180 mg/dL (NICE-SUGAR target); avoid hypoglycemia <70 mg/dL; transition to subcutaneous when tolerating enteral nutrition Hypoglycemia risk; requires frequent glucose monitoring Glucose q1-2h during infusion; q4-6h when stable; watch for hypokalemia - ROUTINE - STAT
DVT prophylaxis: Enoxaparin SC Immobilized ICU patients at high risk for VTE; ICUAW patients are bedbound 40 mg :: SC :: daily :: 40 mg SC daily; adjust for renal function (CrCl <30: 30 mg SC daily or use UFH) Active bleeding; platelets <50K; CrCl <30 (use heparin instead) Platelets q3 days; anti-Xa if renal impairment; signs of bleeding - ROUTINE - ROUTINE
DVT prophylaxis: Heparin SC (renal alternative) SC VTE prophylaxis when enoxaparin contraindicated due to renal impairment 5000 units :: SC :: q8h :: 5000 units SC q8h; use when CrCl <30 mL/min Active bleeding; HIT history Platelets q3 days for HIT surveillance - ROUTINE - ROUTINE
Pneumatic compression devices - VTE prophylaxis adjunct for all immobilized ICUAW patients; use in addition to pharmacologic prophylaxis Apply bilaterally on admission :: - :: continuous :: Apply bilaterally; continue until patient is ambulatory; use as monotherapy only if pharmacologic anticoagulation contraindicated Acute DVT in affected limb; severe peripheral vascular disease Skin integrity daily; device function STAT STAT - STAT
Stress ulcer prophylaxis: Famotidine IV GI prophylaxis for mechanically ventilated patients with ICUAW 20 mg :: IV :: BID :: 20 mg IV q12h; transition to PO when tolerating enteral feeds Severe renal impairment (dose adjust) None significant - ROUTINE - ROUTINE
Stress ulcer prophylaxis: Pantoprazole IV GI prophylaxis alternative; use if high bleed risk (coagulopathy, prior GI bleed) 40 mg :: IV :: daily :: 40 mg IV daily; transition to PO when tolerating enteral feeds None significant C. difficile risk with prolonged use - ROUTINE - ROUTINE

3B. Symptomatic Treatments

Treatment Route Indication Dosing Contraindications Monitoring ED HOSP OPD ICU
Gabapentin PO Neuropathic pain from CIP (burning, tingling, allodynia); common in recovery phase 300 mg :: PO :: qHS :: Start 300 mg PO qHS; titrate by 300 mg/day q1-3 days; target 900-1800 mg/day divided TID; max 3600 mg/day; dose adjust for renal function Severe renal impairment (dose adjust per CrCl); oversedation risk Sedation, dizziness, peripheral edema; renal function for dose adjustment - ROUTINE ROUTINE ROUTINE
Pregabalin PO Neuropathic pain alternative to gabapentin; may be better tolerated 75 mg :: PO :: BID :: Start 75 mg PO BID; increase to 150 mg BID after 3-7 days; max 300 mg BID (600 mg/day); dose adjust for renal function Renal impairment (dose adjust); angioedema history Sedation, weight gain, peripheral edema; renal function - ROUTINE ROUTINE ROUTINE
Duloxetine PO Neuropathic pain and concurrent depression; dual benefit in ICUAW recovery 30 mg :: PO :: daily :: Start 30 mg PO daily x 1 week, then increase to 60 mg daily; max 120 mg/day Severe hepatic impairment; concurrent MAOIs; uncontrolled narrow-angle glaucoma LFTs; blood pressure; serotonin syndrome signs; mood - ROUTINE ROUTINE -
Acetaminophen PO/IV Musculoskeletal pain and general discomfort from immobility 650 mg :: PO :: q6h :: 650-1000 mg PO/IV q6h; max 4 g/day (2 g/day if hepatic impairment) Severe liver disease; hepatic impairment (reduce max dose) LFTs if prolonged use STAT ROUTINE ROUTINE STAT
Melatonin PO ICU delirium prevention and sleep-wake cycle restoration; disrupted sleep worsens ICUAW 3 mg :: PO :: qHS :: 3-5 mg PO qHS; administer at consistent time to promote circadian rhythm None significant Sleep quality; delirium assessment - ROUTINE - ROUTINE
Docusate sodium PO Constipation from immobility and opioid use 100 mg :: PO :: BID :: 100 mg PO BID GI obstruction Bowel function daily - ROUTINE ROUTINE ROUTINE
Senna PO Constipation when docusate alone is insufficient 8.6 mg :: PO :: qHS :: 8.6-17.2 mg PO qHS; may increase to BID GI obstruction; acute abdomen Bowel function - ROUTINE ROUTINE -
Polyethylene glycol (MiraLAX) PO Constipation refractory to docusate and senna 17 g :: PO :: daily :: 17 g PO daily dissolved in 8 oz water GI obstruction Bowel function; electrolytes with prolonged use - ROUTINE ROUTINE -
Sertraline PO Depression and anxiety during prolonged ICU stay and recovery; common comorbidity in ICUAW 25 mg :: PO :: daily :: Start 25-50 mg PO daily; titrate by 25-50 mg q1-2 weeks; max 200 mg/day Concurrent MAOIs; QT prolongation risk Mood assessment; suicidality monitoring (first 4 weeks); serotonin syndrome signs - ROUTINE ROUTINE -
Trazodone PO Insomnia during ICU recovery when melatonin insufficient 25 mg :: PO :: qHS :: Start 25-50 mg PO qHS; max 100 mg qHS for insomnia Severe hepatic impairment; concurrent MAOIs Sedation; orthostatic hypotension; priapism (rare) - ROUTINE ROUTINE -
Cholecalciferol (Vitamin D3) PO Vitamin D deficiency is prevalent in ICU patients and contributes to muscle weakness 2000 IU :: PO :: daily :: 2000 IU PO daily for maintenance; 50,000 IU PO weekly x 8 weeks if deficient (<20 ng/mL), then 2000 IU daily Hypercalcemia; granulomatous disease 25-OH vitamin D level at 8-12 weeks; calcium - ROUTINE ROUTINE ROUTINE

3C. Second-line/Refractory

Treatment Route Indication Dosing Contraindications Monitoring ED HOSP OPD ICU
Amitriptyline PO Neuropathic pain refractory to gabapentin/pregabalin; also helps insomnia 10 mg :: PO :: qHS :: Start 10-25 mg PO qHS; titrate by 10-25 mg q1-2 weeks; max 150 mg/day Arrhythmia; recent MI; urinary retention; angle-closure glaucoma; elderly (anticholinergic burden) ECG at baseline and if dose >100 mg; anticholinergic side effects; QTc - ROUTINE ROUTINE -
Lidocaine patch 5% TOP Localized neuropathic pain; adjunctive to systemic agents 1 patch :: TOP :: daily :: Apply up to 3 patches to painful area for 12h on/12h off Allergy to amide anesthetics; broken skin at application site Skin irritation at application site - ROUTINE ROUTINE -
Methylphenidate PO Severe fatigue and cognitive impairment during ICUAW recovery when non-pharmacologic measures insufficient 5 mg :: PO :: BID :: Start 5 mg PO BID (morning and noon); max 20 mg BID; avoid afternoon dosing to prevent insomnia Severe anxiety; cardiac arrhythmia; uncontrolled hypertension; concurrent MAOIs Blood pressure; heart rate; appetite; sleep; mood; abuse potential - EXT ROUTINE -
Modafinil PO Persistent fatigue during ICUAW recovery; alternative to methylphenidate 100 mg :: PO :: daily :: Start 100 mg PO daily in AM; max 200 mg daily Severe hepatic impairment; cardiac arrhythmia Blood pressure; hepatic function; mood; sleep - EXT ROUTINE -

3D. Disease-Modifying or Chronic Therapies

No disease-specific pharmacologic therapy has been proven effective for CIM or CIP. Management is supportive and preventive. The following interventions target modifiable risk factors and rehabilitation.

Treatment Route Indication Dosing Pre-Treatment Requirements Contraindications Monitoring ED HOSP OPD ICU
Early mobilization protocol - Prevention and treatment of ICUAW; reduces duration of mechanical ventilation and ICU length of stay Structured protocol :: - :: daily :: Phase 1 (passive ROM) within 24-48h of ICU admission; Phase 2 (active-assisted exercises) when patient alert; Phase 3 (sitting, standing, ambulation) when hemodynamically stable; minimum 20-30 min sessions BID Hemodynamic stability (MAP >65, no active vasopressor uptitration); adequate oxygenation (FiO2 <0.6, PEEP <10); no active arrhythmia; no active hemorrhage Active hemorrhage; unstable fractures; severe hemodynamic instability requiring high-dose vasopressors; acute MI; unsecured airway Heart rate, blood pressure, SpO2 during sessions; RASS sedation score; MRC sum score weekly - STAT ROUTINE STAT
Corticosteroid minimization IV/PO Minimize corticosteroid exposure as major risk factor for CIM; taper to lowest effective dose as rapidly as clinically feasible Individualized taper :: IV/PO :: daily :: Reassess corticosteroid indication daily; taper to lowest effective dose; discontinue if not clearly indicated; avoid concurrent use with NMBAs when possible Document clear indication for continued steroids; review alternatives Do not abruptly discontinue if patient has been on >7 days (adrenal suppression risk) Glucose (steroid-induced hyperglycemia); blood pressure; adrenal function if tapering after prolonged course - ROUTINE - STAT
Neuromuscular blocking agent (NMBA) minimization IV Minimize NMBA exposure as risk factor for ICUAW; use train-of-four monitoring to avoid deep paralysis Individualized :: IV :: continuous :: If NMBA required (e.g., ARDS, refractory ICP), use lowest effective dose guided by train-of-four (TOF) monitoring; target 1-2/4 twitches; daily sedation/paralysis vacation if feasible; discontinue NMBA as soon as clinically possible Document clear indication (severe ARDS, refractory ICP, open abdomen) Concurrent high-dose corticosteroids (greatly increases CIM risk); avoid unless absolutely necessary Train-of-four q4h; daily attempt to discontinue; document indication daily - - - STAT
Enteral nutrition (high-protein) PO/EN Protein supplementation to support muscle preservation and recovery; protein catabolism is accelerated in ICUAW 1.2-2.0 g/kg/day protein :: EN :: daily :: Target protein 1.2-2.0 g/kg/day (adjusted body weight if obese); initiate enteral nutrition within 24-48h of ICU admission; caloric target 25-30 kcal/kg/day; avoid overfeeding Functional GI tract; hemodynamic stability (MAP >60 on stable or decreasing vasopressors) GI obstruction; uncontrolled shock (delay until resuscitated); bowel ischemia Prealbumin weekly; nitrogen balance; feeding tolerance (residuals); glucose - STAT ROUTINE STAT
Tight glycemic control protocol IV/SC Target glucose 140-180 mg/dL to reduce ICUAW incidence; hyperglycemia independently increases CIM/CIP risk Insulin per protocol :: IV/SC :: continuous :: IV insulin infusion in ICU targeting 140-180 mg/dL; transition to basal-bolus SC insulin when tolerating nutrition; avoid tight control <110 (increased mortality per NICE-SUGAR) Active hypoglycemia Adrenal insufficiency (may require stress-dose steroids before aggressive glucose control) Glucose q1-2h on infusion; q4-6h on SC insulin; HbA1c at discharge - ROUTINE ROUTINE STAT
Sedation minimization protocol IV Daily sedation interruption and light sedation targets reduce ICUAW risk and facilitate early mobilization RASS target -1 to 0 :: IV :: continuous :: Daily spontaneous awakening trial (SAT); target RASS -1 to 0; use analgesia-first approach (pain, delirium, then sedation); prefer dexmedetomidine or propofol over benzodiazepines (benzodiazepines increase delirium and ICUAW risk) Pain adequately controlled; no active seizures; no procedures requiring deep sedation Active seizures; procedures requiring deep sedation; severe agitation endangering patient safety (titrate to lowest necessary level) RASS q4h; CAM-ICU for delirium BID; pain assessment - - - STAT

4. OTHER RECOMMENDATIONS

4A. Referrals & Consults

Recommendation ED HOSP OPD ICU
Neurology consultation for diagnosis confirmation and electrodiagnostic planning (NCS/EMG) to differentiate CIM, CIP, and alternative diagnoses - STAT ROUTINE STAT
Physical therapy for early mobilization protocol initiation, passive/active ROM exercises, progressive strengthening, and functional mobility training - STAT ROUTINE STAT
Occupational therapy for upper extremity strengthening, ADL retraining, adaptive equipment assessment, and fine motor recovery - URGENT ROUTINE URGENT
Speech-language pathology for swallowing evaluation given risk of pharyngeal weakness and aspiration in ICUAW patients - URGENT ROUTINE URGENT
Respiratory therapy for ventilator weaning protocols, tracheostomy care, pulmonary rehabilitation, and secretion management - STAT - STAT
Rehabilitation medicine (physiatry) for comprehensive rehabilitation planning and disposition (inpatient rehab vs skilled nursing facility) - ROUTINE ROUTINE ROUTINE
Nutrition/Dietitian for enteral nutrition optimization, protein target (1.2-2.0 g/kg/day), caloric assessment, and micronutrient supplementation - URGENT ROUTINE URGENT
Pulmonology for ventilator management optimization, weaning strategies, and tracheostomy decision if prolonged ventilation anticipated - ROUTINE - URGENT
Pain management for refractory neuropathic pain not responding to first-line gabapentinoids - ROUTINE ROUTINE ROUTINE
Social work for discharge planning, family support, insurance authorization for rehabilitation, and community resources - ROUTINE ROUTINE -
Psychology/Psychiatry for ICU-acquired PTSD, depression, anxiety, and cognitive dysfunction screening and treatment - ROUTINE ROUTINE ROUTINE
Palliative care for goals-of-care discussion if severe ICUAW with poor prognosis, prolonged ventilator dependence, or significant comorbidities - ROUTINE - ROUTINE

4B. Patient Instructions

Recommendation ED HOSP OPD
Recovery from ICU-acquired weakness typically takes weeks to months; CIM generally recovers faster than CIP (inform patient and family to set expectations) - ROUTINE ROUTINE
Participate actively in all physical and occupational therapy sessions as tolerated to maximize recovery potential - ROUTINE ROUTINE
Report new or worsening weakness, numbness, tingling, or breathing difficulty to medical team immediately (may indicate complication or alternative diagnosis) - ROUTINE ROUTINE
Continue home exercise program as prescribed by physical therapy between formal sessions to maintain gains - ROUTINE ROUTINE
Fall precautions: use assistive devices (walker, cane) as recommended; remove tripping hazards at home; do not attempt stairs without supervision until cleared - ROUTINE ROUTINE
Do not drive until strength and coordination have recovered sufficiently and cleared by neurologist or physiatrist - ROUTINE ROUTINE
Follow-up with neurology in 4-8 weeks after discharge for strength assessment and possible repeat NCS/EMG to track recovery - ROUTINE ROUTINE
Adequate nutrition with high-protein diet (1.2-2.0 g/kg/day protein) supports muscle recovery - ROUTINE ROUTINE
Mental health is important during recovery; report symptoms of depression, anxiety, or PTSD to healthcare provider (common after prolonged ICU stay) - ROUTINE ROUTINE

4C. Lifestyle & Prevention

Recommendation ED HOSP OPD
Early mobilization within 24-48 hours of ICU admission when hemodynamically stable to prevent and mitigate ICUAW - STAT -
High-protein nutrition (1.2-2.0 g/kg/day) to support muscle preservation and recovery during critical illness - ROUTINE ROUTINE
Smoking cessation to optimize pulmonary function and tissue oxygenation for nerve and muscle recovery - ROUTINE ROUTINE
Glycemic control (target glucose 140-180 mg/dL in ICU; HbA1c <7% outpatient) to reduce ongoing neuromyopathy risk - ROUTINE ROUTINE
Avoid unnecessary corticosteroids and neuromuscular blocking agents to reduce ICUAW risk in current and future ICU admissions - ROUTINE ROUTINE
Graduated exercise program starting with low-intensity activities and progressing as tolerated to rebuild strength and endurance - ROUTINE ROUTINE
Frequent repositioning every 2 hours during immobility to prevent pressure ulcers and contractures - STAT -
Adequate sleep hygiene with consistent sleep-wake cycles to promote neurological recovery and reduce delirium - ROUTINE ROUTINE
Vitamin D supplementation if deficient to support muscle function and bone health during recovery - ROUTINE ROUTINE
Alcohol avoidance as alcohol worsens neuropathy and impairs muscle recovery - ROUTINE ROUTINE

═══════════════════════════════════════════════════════════════ SECTION B: REFERENCE (Expand as Needed) ═══════════════════════════════════════════════════════════════

5. DIFFERENTIAL DIAGNOSIS

Alternative Diagnosis Key Distinguishing Features Tests to Differentiate
Guillain-Barré syndrome (GBS) Ascending paralysis, areflexia, can develop during ICU stay; antecedent infection; albuminocytologic dissociation on LP; may be monophasic; usually not associated with prolonged steroid/NMBA exposure CSF analysis (elevated protein, normal WBC); NCS/EMG (demyelinating pattern in AIDP); anti-ganglioside antibodies; clinical timeline
Myasthenia gravis exacerbation Fatigable weakness, ptosis, diplopia, bulbar symptoms; fluctuating course; intact reflexes (usually); responds to cholinesterase inhibitors AChR and MuSK antibodies; repetitive nerve stimulation (decremental); ice pack test; edrophonium test
Prolonged neuromuscular blockade effect History of NMBA use; resolves within hours to days of NMBA discontinuation; train-of-four monitoring shows persistent block; no sensory involvement Train-of-four monitoring (incomplete recovery of twitches); clinical resolution after NMBA clearance (typically <48h); NCS/EMG normal after drug clearance
Spinal cord injury/compression Sensory level; upper motor neuron signs below level (hyperreflexia, Babinski); bladder dysfunction; back pain MRI spine (cord compression, hemorrhage, infarction); clinical exam with sensory level
Central pontine myelinolysis (osmotic demyelination) History of rapid sodium correction; quadriparesis with pseudobulbar features; locked-in syndrome; MRI brain lesion MRI brain (pontine or extrapontine demyelination on T2/FLAIR); serum sodium correction history
Rhabdomyolysis Very elevated CK (typically >10,000 IU/L); dark urine; acute kidney injury; history of crush injury, statins, or seizures CK markedly elevated; urine myoglobin; renal function; clinical context
Acute necrotizing myopathy Very elevated CK; myopathic EMG; may occur with statin use in ICU; requires muscle biopsy for definitive diagnosis CK markedly elevated; NCS/EMG (myopathic); muscle biopsy (necrosis without inflammation); anti-HMGCR or anti-SRP antibodies
Lambert-Eaton myasthenic syndrome (LEMS) Proximal weakness improving with repeated effort; autonomic dysfunction; associated with small cell lung cancer; incremental response on RNS Anti-VGCC antibodies; repetitive nerve stimulation (incremental at high-rate); CT chest for malignancy
Disuse atrophy Weakness proportional to immobility duration; normal NCS/EMG; no sensory changes; normal CK NCS/EMG normal; clinical context; muscle ultrasound (atrophy without echogenicity changes)
Hypothyroid myopathy Proximal weakness; elevated CK; delayed relaxation of reflexes; other hypothyroid features (edema, cold intolerance) TSH elevated; free T4 low; CK elevated; NCS/EMG (myopathic)
Acute inflammatory myopathy (polymyositis/dermatomyositis) Proximal weakness; elevated CK (often >5000); skin changes in dermatomyositis; may respond to immunosuppression CK markedly elevated; myositis-specific antibodies; MRI muscle (edema); muscle biopsy (inflammatory infiltrate)
Steroid myopathy (chronic) Proximal weakness; normal CK; history of chronic corticosteroid use; no sensory involvement; gradual onset Normal CK; NCS/EMG (myopathic MUPs); clinical improvement with steroid taper; muscle biopsy (type 2 fiber atrophy without necrosis)

6. MONITORING PARAMETERS

Parameter Frequency Target/Threshold Action if Abnormal ED HOSP OPD ICU
MRC sum score (6 bilateral muscle groups: shoulder abduction, elbow flexion, wrist extension, hip flexion, knee extension, ankle dorsiflexion) Daily in ICU when patient cooperative; weekly on floor; each outpatient visit MRC sum score >=48/60 (ICUAW defined as <48/60); individual muscle >=4/5 MRC <48/60: confirm ICUAW diagnosis; intensify rehabilitation; if declining, reassess for alternative or superimposed diagnosis - ROUTINE ROUTINE STAT
Blood glucose q1-2h on insulin drip; q4-6h on SC insulin; fasting + pre-meals on floor 140-180 mg/dL in ICU; <180 mg/dL on floor Adjust insulin regimen; avoid hypoglycemia <70 mg/dL; persistent hyperglycemia worsens ICUAW STAT STAT ROUTINE STAT
Respiratory function (FVC if cooperative; ventilator mechanics if intubated) q4-6h if on ventilator; daily if on floor; each outpatient visit FVC >15 mL/kg supports weaning; improving trend Declining FVC: assess for pneumonia, fluid overload, worsening weakness; adjust ventilator support - ROUTINE ROUTINE STAT
Negative inspiratory force (NIF/MIP) q4-6h if ventilator-dependent; daily on floor NIF more negative than -20 cmH2O (adequate for weaning) NIF weaker than -20 cmH2O: not ready for extubation; continue respiratory therapy - ROUTINE ROUTINE STAT
Diaphragm ultrasound (thickness and excursion) Weekly in ICU; monthly outpatient if diaphragm weakness present Thickness >2mm; thickening fraction >30%; excursion >10mm Declining values: diaphragm atrophy worsening; adjust ventilator settings to promote diaphragm activity (avoid excessive support) - ROUTINE ROUTINE ROUTINE
CK (creatine kinase) q48-72h in acute phase; weekly during recovery; PRN outpatient Trending toward normal Persistently or newly elevated: reassess for ongoing muscle injury; rhabdomyolysis; inflammatory myopathy - ROUTINE ROUTINE ROUTINE
Electrolytes (K, Mg, Phos, Ca) Daily in ICU; q48-72h on floor; each outpatient visit Normal ranges Replete aggressively; hypokalemia, hypomagnesemia, hypophosphatemia all worsen weakness STAT ROUTINE ROUTINE STAT
Prealbumin/Albumin Weekly in ICU and on floor; monthly outpatient Prealbumin >15 mg/dL; albumin >3.0 g/dL Low values: optimize nutrition; increase protein intake; nutrition consult - ROUTINE ROUTINE ROUTINE
Sedation level (RASS) q4h in ICU RASS -1 to 0 (light sedation) Over-sedation: reduce sedatives; switch from benzodiazepines to dexmedetomidine or propofol - - - STAT
Delirium screen (CAM-ICU) q8-12h in ICU; daily on floor Negative (no delirium) Positive: delirium workup; reduce deliriogenic medications (benzodiazepines, anticholinergics); non-pharmacologic interventions - ROUTINE - STAT
Skin integrity Every shift in ICU; daily on floor Intact skin; no pressure injuries Pressure ulcer: reposition more frequently; wound care consult; pressure-relieving mattress - ROUTINE - STAT
Functional status (Barthel Index or FIM score) Weekly in hospital; each outpatient visit Improving trend; score guides disposition planning Not improving: reassess rehabilitation plan; consider transfer to higher-level rehabilitation; assess for barriers to recovery - ROUTINE ROUTINE ROUTINE
NCS/EMG follow-up At 2-4 weeks after initial; repeat at 3-6 months if recovering; annually if persistent deficits Improvement in CMAP amplitudes; reinnervation on EMG; resolution of myopathic changes No improvement at 3-6 months: consider muscle biopsy; reassess diagnosis; discuss prognosis with patient/family - ROUTINE ROUTINE ROUTINE
Depression/Anxiety screening (PHQ-9, GAD-7) Weekly on floor; each outpatient visit PHQ-9 <5 (minimal); GAD-7 <5 (minimal) PHQ-9 >=10 or GAD-7 >=10: initiate treatment; psychiatry referral; assess for PTSD - ROUTINE ROUTINE -

7. DISPOSITION CRITERIA

Disposition Criteria
Discharge home MRC sum score >=48/60; ambulatory with or without assistive device; safe swallowing; adequate pain control on oral medications; stable respiratory function off supplemental O2; reliable outpatient follow-up; home exercise program established; family/caregiver support
Admit to floor New-onset ICUAW identified in ICU patient transitioning to floor; MRC sum score 36-48/60; hemodynamically stable; off vasopressors; not ventilator-dependent; requires ongoing PT/OT; needs continued monitoring
Admit to ICU Ventilator-dependent with ICUAW; acute respiratory failure from neuromuscular weakness; hemodynamic instability; need for continuous monitoring; initial evaluation of weakness in critically ill patient
Transfer to higher level of care Need for specialized electrodiagnostic testing (DMS) not available locally; complex ventilator weaning requiring neuromuscular expertise; need for muscle biopsy for atypical presentation
Inpatient rehabilitation Significant motor deficits (MRC sum score 36-48/60); able to tolerate 3 hours/day of therapy; medically stable; off mechanical ventilation (or stable tracheostomy with portable ventilator); good prognosis for functional improvement
Long-term acute care (LTAC) Ventilator-dependent >21 days; unable to tolerate intensive rehabilitation; requires ongoing skilled nursing and ventilator weaning; medically complex
Skilled nursing facility (SNF) Unable to tolerate 3 hours/day of therapy; requires ongoing nursing care; not ready for home but not requiring acute hospital level care

8. EVIDENCE & REFERENCES

Recommendation Evidence Level Source
ICUAW defined as MRC sum score <48/60 in cooperative ICU patients Class I, Level B Stevens et al. Crit Care Med 2009
Sepsis and multi-organ failure are primary risk factors for ICUAW Class I, Level A De Jonghe et al. JAMA 2002
NCS/EMG differentiates CIM (myopathic, normal SNAPs) from CIP (axonal sensorimotor) Class I, Level B Latronico & Bolton. Lancet Neurol 2011
Direct muscle stimulation (DMS) differentiates CIM from CIP in uncooperative patients Class IIa, Level B Rich et al. Muscle Nerve 1996
Hyperglycemia is independent risk factor; glycemic control reduces ICUAW incidence Class I, Level A Van den Berghe et al. NEJM 2001; Hermans et al. Lancet 2007
NICE-SUGAR target glucose 140-180 mg/dL (tight control increases mortality) Class I, Level A NICE-SUGAR Investigators. NEJM 2009
Corticosteroids combined with NMBAs greatly increase CIM risk Class I, Level B De Jonghe et al. Crit Care Med 2009; Hermans et al. Intensive Care Med 2014
Early mobilization reduces ICUAW incidence and improves outcomes Class I, Level A Schweickert et al. Lancet 2009
Early mobilization is safe in mechanically ventilated patients Class I, Level B Morris et al. Crit Care Med 2008
Minimizing sedation reduces delirium and ICUAW risk (ABCDEF bundle) Class I, Level A Barnes-Daly et al. Crit Care Med 2017
CIM has better prognosis than CIP; most CIM patients recover within 3-6 months Class II, Level B Koch et al. Neurology 2012; Guarneri et al. J Neurol Neurosurg Psychiatry 2008
Muscle ultrasound detects early muscle wasting in ICU patients Class IIa, Level B Puthucheary et al. JAMA 2013
Diaphragm ultrasound predicts weaning success Class IIa, Level B DiNino et al. J Crit Care 2014
Protein intake 1.2-2.0 g/kg/day recommended for critically ill patients Class IIa, Level B McClave et al. JPEN 2016 (ASPEN/SCCM Guidelines)
No specific pharmacologic treatment proven effective for CIM or CIP Class I, Level C Hermans & Van den Berghe. NEJM 2015
Electrical muscle stimulation may attenuate muscle wasting (emerging evidence) Class IIb, Level C Routsi et al. Crit Care Med 2010
ICU-acquired weakness is associated with increased mortality and prolonged mechanical ventilation Class I, Level A Fan et al. CMAJ 2014
ABCDEF bundle implementation reduces ICUAW and delirium Class I, Level B Pun et al. Lancet Respir Med 2019
Vitamin D deficiency is associated with ICU-acquired weakness Class IIb, Level C Amrein et al. JAMA 2014

CHANGE LOG

v1.1 (January 30, 2026) - Standardized structured dosing format across all treatment tables (Sections 3A-3D) - Fixed Gabapentin, Pregabalin, Duloxetine, Sertraline, Trazodone, Amitriptyline, Methylphenidate, Modafinil dosing to use single starting dose before :: separators - Fixed Acetaminophen, Melatonin, Docusate, Senna, Polyethylene glycol, Lidocaine patch, Cholecalciferol dosing format - Added missing frequency fields in Section 3D protocol entries (corticosteroid minimization, NMBA minimization, enteral nutrition, glycemic control, sedation minimization) - Replaced arrow character in sedation protocol text to avoid encoding issues - Updated version to 1.1; added REVISED date - Validated all 6 quality domains (54/60, 90%)

v1.0 (January 30, 2026) - Initial template creation - Comprehensive 8-section format covering CIM, CIP, and combined CINM - Standardized treatment tables with structured dosing format - Evidence-based recommendations with PubMed citations - Emphasis on prevention (glycemic control, steroid/NMBA minimization, early mobilization) - Complete setting coverage (ED, HOSP, OPD, ICU)


APPENDIX A: MRC SUM SCORE ASSESSMENT

Medical Research Council (MRC) Sum Score for ICU-Acquired Weakness

Assess 6 bilateral muscle groups (12 total assessments) on a 0-5 scale. Maximum score = 60.

Muscle Group Movement Tested Right (0-5) Left (0-5)
Shoulder abduction Deltoid _ _
Elbow flexion Biceps _ _
Wrist extension Wrist extensors _ _
Hip flexion Iliopsoas _ _
Knee extension Quadriceps _ _
Ankle dorsiflexion Tibialis anterior _ _

MRC Grading Scale:

Grade Description
0 No visible contraction
1 Visible contraction without limb movement
2 Movement with gravity eliminated
3 Movement against gravity
4 Movement against gravity with some resistance
5 Normal strength

Interpretation:

Total Score Interpretation
60 Normal strength
48-59 Mild weakness (not ICUAW)
<48 ICU-acquired weakness (ICUAW)
<36 Severe ICUAW

Requirements: Patient must be awake and cooperative (RASS 0 to +1); GCS verbal component >=4; assess at least 3 consecutive sessions to confirm reliability.

APPENDIX B: ELECTRODIAGNOSTIC DIFFERENTIATION OF CIM vs CIP

Feature CIM (Critical Illness Myopathy) CIP (Critical Illness Polyneuropathy) Combined CINM
Motor NCS (CMAP) Reduced amplitudes; may have prolonged duration Reduced amplitudes Reduced amplitudes
Sensory NCS (SNAP) NORMAL (key differentiator) Reduced amplitudes (axonal) Reduced amplitudes
Conduction velocities Normal Normal or mildly reduced Normal or mildly reduced
EMG (volitional) Myopathic: small, polyphasic, early recruitment Neuropathic: large, polyphasic, reduced recruitment, fibrillations Mixed myopathic and neuropathic
Direct muscle stimulation (DMS) Reduced nerve:muscle ratio (<0.5); reduced direct CMAP Preserved nerve:muscle ratio; reduced CMAPs on both Variable
CK level Often elevated (1000-5000 IU/L) Usually normal Variably elevated
Sensory exam Normal Reduced distally (stocking-glove) Reduced distally
Reflexes Reduced or absent Reduced or absent Reduced or absent
Prognosis Better; most recover in 3-6 months Worse; recovery may take 6-12+ months; some have permanent deficits Intermediate
Risk factors Corticosteroids + NMBAs; high-dose steroids Sepsis; multi-organ failure Overlap of both risk profiles

APPENDIX C: ICUAW PREVENTION AND EARLY MOBILIZATION PROTOCOL

Phase 1: Passive (Patient sedated or non-cooperative; RASS -3 to -1) - Passive range of motion all extremities BID (minimum) - Positioning changes q2h - Neuromuscular electrical stimulation (if available) - Nutritional optimization initiated

Phase 2: Active-Assisted (Patient awakening; RASS -1 to 0) - Active-assisted range of motion - Bed exercises (leg lifts, arm raises) - Sitting at edge of bed - Progressive resistance exercises as tolerated

Phase 3: Active Mobilization (Patient alert; RASS 0 to +1) - Active standing with assistance - Transfer to chair (minimum 20 min BID) - Ambulation with assistive device - Progressive exercise program (resistance bands, weights)

Phase 4: Independent Mobilization (Medically stable; off vasopressors) - Independent ambulation with supervision - Stair training - Endurance exercises - Discharge exercise program education

Safety Criteria for Mobilization: - MAP >65 mmHg (not on increasing vasopressor doses) - HR 60-130 bpm - SpO2 >90% on current O2 support - FiO2 <0.6 and PEEP <10 cmH2O (if ventilated) - No active arrhythmia - No active hemorrhage - No unstable fractures or recent surgery precluding movement - Adequate staffing and equipment available

Stop Criteria During Session: - SpO2 <88% for >1 minute - Systolic BP <90 or >200 mmHg - HR <50 or >150 bpm - New arrhythmia - Patient distress or agitation - Fall or loss of support device (IV, airway, catheter)