1. Critical Illness Myopathy (CIM)
Rebekah Rubin, SPT

2. Critical Illness
Chronic critical illness patients have decreased function and quality of life, increased morbidity and mortality rates and high costs of care
Intensive care unit-acquired weakness (ICUAW) is a clinical diagnosis of weakness
Three component conditions: critical illness polyneuropathy (CIP), critical illness myopathy (CIM), and critical illness neuromyopathy (CINM).
CIM and CIP often co-exist
Occurs in 33-57% of pts who have been in the ICU >7 days
68-100% in pts w/ sepsis and SIRS

3. What is it?
William Osler, 19th century first described “rapid loss of flesh” in patients with prolonged sepsis
Mid 20th century CIM was first used as a distinct pathology
CIM seems to be a syndrome of ‘symmetric weakness of all extremities, of muscle wasting, hyporeflexia and failure to wean from mechanical ventilation.’
Three Subtypes: CIM, Thick Filament Myopathy, Acute Necrotizing Myopathy of Intensive Care
Thought to be a manifestation of systemic inflammatory response syndrome(SIRS)
It is a primary myopathy and is not secondary to muscle denervation
Clinical syndrome that typically occurs in the intensive care unit in patients who have been treated with multiple drugs
CIM-changes are small and accompany CIP Type 1 and 2 fibers. CK values are normal and have a good prognosis
TFM-selective loss of myosin filaments w/ CK levels elevated, OK prognosis, typically a result of medication
ANMoIC-poor outcome, eleveated serum CK

4. Signs and Symptoms
Most common are diffuse weakness and a failure to wean from mechanical ventilation.
Proximal and distal muscle weakness
flaccid and usually symmetrical
Cranial Nerves intact
Reflexes typically diminished
Sensation remains intact

5. Risk Factors? Prolonged ICU stay Acute respiratory disorder Inactivity
Drugs(corticosteroids, neuromuscular blocking agents)
Sepsis
Hyperglycemia
Female
Multi-Organ Dysfunction
Renal Failure
acute respiratory distress syndrome, pneumonia, or severe asthma

6. Predecessors to icu-acquired weakness

7. Diagnosis? Muscle biopsy – GOLD STANDARD
fiber atrophy, loss of myosin, fatty degeneration, and necrosis
Needle EMG or nerve conduction studies
In the case of CIM, there should be no major problems with conduction
Reduced amplitude and duration of action potentials
Some muscles can be electrically inexcitiable with direct stimulation
For patients with CIM, in contrast to those with CIP, nerve conduction studies demonstrate preserved sensory nerve action potentials.
 Compound muscle action potential amplitudes may be reduced, and the duration of the potentials may be prolonged, reflecting slowed muscle fiber conduction velocity.
 In some patients, muscle may be electrically inexcitable, and no muscle fiber action potentials can be recorded even with direct electrical stimulation of muscle

8. Differential Diagnosis
Spinal cord disorder
Guillain-Barre Syndrome
Diabetic polyneuropathy
Myasthenia gravis
Toxin and drugs
Porphyria
Acute Quadriplegic Myopathy

9. Treatment
Early and complete recovery may occur with successful treatment of the critical illness, and withdrawal of the medications.
Multimodal Approach
Early Dx
Intensive Insulin Therapy
Minimal Sedation
Early Therapy
EMS
There are no published RCTs or quasi-RCTs that examine whether physical rehabilitation interventions improve activities of daily living for people with CIP and CIM. Large RCTs, which are feasible, need to be conducted to explore the role of physical rehabilitation interventions for people with CIP and CIM. 

10. ROM Exercise and Functional Mobility
Aimed to improve function and reduce disabilities from peripheral muscle weakness
Started as soon as possible, once pt is hemodynamically stable- decreases length of stay and decreases immobilization risks
Passive, Active, Active Assist, Resisted, PNF Diagonals
Bed mobility, balance, transfer training, gait
Therapeutic exercises (both active and passive) are aimed to improve function and reduce disabilities and complications like muscle shortening, contractures, and deformities. Studies have shown that more than one third of patients with prolonged stay of two or more weeks in ICU had at least two functionally significant joint contractures clearly indicating immobility as a major reason for development of contractures and a contributing factor for muscle wasting and muscle weakness in critically ill patients.
Active or passive mobilization and muscle training should be instituted early
Positioning, splinting, passive mobilization and muscle stretching should be used to preserve joint mobility and skeletal muscle length in patients unable to move spontaneously and administered jointly w/ nursing staff

11. “ Feasibility of physical and occupational therapy beginning from initiation of mechanical ventilation.” (Pohlam et al.)
Patients underwent sedative interruption followed by PT/OT every hospital day
MEASUREMENTS AND RESULTS:
49 mechanically ventilated patients
received PT/OT ~ 1.5 days after intubation on 90% of ICU days
subjects sat at the edge of the bed in 69% of all sessions
transferred from bed to chair in 33%, stood in 33%, and ambulated during 15% of sessions
4% of sessions aborted
CONCLUSION:
Early physical and occupational therapy is feasible from the onset of mechanical ventilation despite high illness acuity and presence of life support devices. Adverse events were uncommon
While endotracheally intubated pts participated in session
Median distance of 15 ft
Therapeutic exercises may begin as soon as the patient is hemodynamically stable to prevent prolonged hospitalization and associated immobilization risks and may be one of the key factors for patients’ recovery. Exercises in ICU offer well established physical and psychological benefits and additionally reduce oxidative stress and inflammation due to increased anti-inflammatory cytokines production. Exercises schedules like trunk control, passive, active and resistive exercises with therabands and weight cuffs, upper and lower limb strengthening exercises, functional training, walking, mobilization with frequent positional changes, respiratory physiotherapy have shown beneficial effects in terms of clinical outcome and early weaning.

13. “Efficacy of EMS in preventing CIPNM in critically ill patients” (Rousti et al.)
Methods
144 consecutive critically ill patients
EMS Group vs. Control Group
CIPNM was diagnosed clinically with the medical research council (MRC) scale for muscle strength
Duration of weaning from mechanical ventilation and intensive care unit (ICU) stay were recorded.
Results
52 pts evaluated w/ MRC: 24 EMS Group/28 Control
EMS Group :3 diagnosed with CIPNM, MRC 58, Weaning Period 1 day
Control Group: 11 diagnosed w/ CIPNM, MRC 52, Weaning Period 3 days
Conclusions
Suggests that daily EMS sessions prevent the development of CIPNM in critically ill patients and also result in shorter duration of weaning.
vastus lateralis, vastus medialis and peroneous longus muscles of both lower extremities duration of the session was 55 minutesPatients of the EMS group received daily EMS sessions
(maximum score 60, <48/60 cut off for diagnosis) by two unblinded independent investigators.
NMES is well tolerated and may preserve the muscle mass of critically ill patients. It may be considered to be an alternative treatment to active exercises, which does not require patient cooperation. Use of NMES has shown to increase muscle strength and reduce the number of hospital days for transfer from bed to chair. Long term use of NMES has shown to have positive effect on tissue healing including redistribution of interface pressures away from the pressure regions with an increase in local blood flow. Regular NMES may increase regional vascularization, hence prevent bed sores in spinal cord injury patients.[22–28] However, though NMES is a promising technique, definite evidence of efficacy is still lacking

14. Respiratory Therapy
Respiratory weakness and difficulty weaning are common complications of CIM
Difficulty with clearing secretions common
Assisted cough techniques, diaphragmatic breathing, pursed-lip breathing

15. Summary
Team Approach
PT/OT/RT/SLP play an important role in restoring function in patients with critical illness.
Evidence shows that rehab can be implemented safely in people who have ICU-acquired weakness when appropriate guidelines are followed.
Start slow and build tolerance.

16. References
Pattanshetty, R., & Gaude, G. (2011). Critical illness myopathy and polyneuropathy - A challenge for physiotherapists in the intensive care units. Indian Journal of Critical Care Medicine Indian J Crit Care Med, 15(2), 78. doi: /
Pohlman, M. C., Schweickert, W. D., Pohlman, A. S., Nigos, C., Pawlik, A. J., Esbrook, C. L., Kress, J. P. (2010). Feasibility of physical and occupational therapy beginning from initiation of mechanical ventilation*. Critical Care Medicine, 38(11), doi: /ccm.0b013e3181f270c3
Routsi, C., Gerovasili, V., Vasileiadis, I., Karatzanos, E., Pitsolis, T., Tripodaki, E. S., Nanas, S. (2010). Electrical muscle stimulation prevents critical illness polyneuromyopathy: A randomized parallel intervention trial. Critical Care Crit Care, 14(2). doi: /cc8987
Visser, L. H. (2006). Critical illness polyneuropathy and myopathy: Clinical features, risk factors and prognosis. Eur J Neurol European Journal of Neurology, 13(11), doi: /j x