ICU-acquired paresis

In a study of 183 COPD patients with acute respiratory failure, 10.4% remained mechanically ventilated 21 days after intubation (11). In the same ICU, the relative risk of remaining ventilated at day 21 was twice as high in patients intubated for acute lung injury (21 of 107) (42). One explanation for the latter observation is the presence of either critical illness polyneuropathy or ICU-acquired paresis (ICUAP). In a study of 95 patients ventilated for at least seven days, one quarter developed ICUAP, resulting in a longer duration of MV (18 vs. 8 days in patients without ICUAP) (43). 

De Jonghe B, Bastuji-Garin S, Sharshar T, et al. Does ICU-acquired paresis lengthen weaning fl om mechanical ventilation Intensive Care Med 2004 30(6) 1117-1121. 

New-onset respiratory muscle weakness may result from conditions that are unique to mechanically ventilated patients, such as ventilator-associated respiratory muscle dysfunction, sepsis-associated myopathy, and ICU-acquired paresis (63). New-onset respiratory muscle weakness may also result from conditions that are not unique to critically ill patients, such as acid-base disorders, electrolyte disturbances, decreased oxygen delivery, and medications (63). 

In the last few years, it has become increasingly apparent that critical illness neuropathy and myopathy often coexist, and it has become common to refer to these patients as simply having ICU-acquired paresis (26,83). ICU-acquired paresis is an independent risk factor of prolonged weaning (26). In an investigation, tight control of hyperglycemia reduced the risk of ICU-acquired paresis and the duration of mechanical ventilation (84). 

The functional outcome of ICU-acquired paresis is not uniform, with 50-60% of patients experiencing complete recovery over two weeks to six months (85-87) and 10-30% experiencing persistent disability, including tetraparesis, tetraplegia, or paraplegia (88,89). Whether ICU-acquired paresis can be prevented, and whether that would result in shorter duration of mechanical ventilation, remains unknown. 

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