Acquired Neuromuscular Disorders in the ICU
ICU-acquired weakness (ICUAW) refers to clinically detectable muscle weakness in
critically ill patients, in the absence of weakness caused by factors other than critical illness.Approximately one-third of critically ill patients have ICUAW.Possible etiologies may includemuscle atrophy/wasting, CIP, CIM, or a combination of these factors.
ICU获得性虚弱是指危重患者在缺乏虚弱致病因素条件下临床上可检测到的肌肉力量减弱，大约有三分之一的危重患者存在ICU获得性虚弱，可能的病因可能包括肌肉萎缩/消瘦，重症多发神经病变（critical illness polyneuropathy，CIP），重症多发肌肉病变（critical illness myopathy，CIM），或综合因素。
Risk Factors for Neuromuscular Disorders and Functional Impairment：
bed rest, corticosteroids, and neuromuscular blockers (NMBs). Among potential risk factors, bed rest is an important modifiable risk factor. Early mobilization and rehabilitation of critically ill patients may help prevent or mitigate the sequelae of bed rest and improve patient outcomes.
Sequelae of Neuromuscular Disorders
ICU-associated neuromuscular disorders have short- and long-term sequelae. Several
studies reported an association between ICUAW and delayed weaning from mechanical ventilation, increased in-hospital costs, and increased mortality.In addition, patients with ICUAW may have a significantly increased risk of death after discharge,and significant impairments in respiratory muscle strength, physical function, and health-related quality of life that persist for at least 2 years. Persistent physical impairment was also reported in other longitudinal studies that followed ARDS survivors up to 5 years following discharge.
Safety of Early Mobilization and Rehabilitation
Mechanically ventilated patients are often considered to have a vulnerable hemodynamic and respiratory status, among other perceived barriers, that may interfere with mobilization.However, the reported rate of adverse events is very low, mostly in the form of transient physiological derangements that resolve without the need for any additional therapy. There is expert consensus that early mobilization and rehabilitation is safe and does not expose mechanically ventilated patients to any significant additional risk, as long as they are closely monitored during and after mobilization.
Commonly Perceived Barriers to Early Mobilization and Rehabilitation
In many centers, current ICU culture represents an important and potentially modifiable
barrier to early mobilization and rehabilitation. Insufficient coordination, timing conflicts with different procedures, and competing patient priorities are common.21,55,56,45 Overcoming these barriers requires a structured multidisciplinary effort, with clear communication and recognition of the importance of early mobilization and rehabilitation.57 Provision of critical care in an ICU with a culture that prioritizes early rehabilitation has been shown to increase the number of mechanically ventilated patients ambulating by three-fold.
The widespread use of sedation in the ICU can be a major barrier to mobilizing critically
ill patients.Combining sedation minimization with early mobility can be done via
implementing the ABCDE bundle,in which all patients undergo daily coordinated spontaneous awakening trials, spontaneous breathing trials, sedation and delirium screening, and early mobility and rehabilitation.A pre-post prospective study of 296 patients showed that applying this bundle was feasible and improved patient outcomes, such as reducing delirium and increasing mobilization out of bed.
Tips:（ABCDE bundle :the awakening and breathing coordination, delirium monitoring/management, and early exercise/mobility bundle.）
ICU里广泛使用镇静剂可能是危重患者活动的一个主要的障碍。通过使用ABCDE bundle 策略可以把镇静最小化和早期活动联合起来。其中所有的患者接受每日唤醒试验，自主呼吸试验，镇静和谵妄筛查，以及早期活动和康复。一个纳入了296例患者的前-后对比的前瞻性研究表明，应用这一bundle策略是可行的而且改善了患者预后，如降低谵妄和增加床下活动能力。
Endotracheal Tube (ETT)
The presence of an ETT is another commonly perceived barrier.To assist with
overcoming this barrier, one study detailed the steps undertaken to start PT and OT interventions after a median of only 1.5 days of intubation in 49 endotracheally intubated patients.Patients underwent daily screening for ten contraindications to PT/OT interventions, followed by daily interruption of sedation until they achieved wakefulness, with PT/OT interventions initiated thereafter. Initiation of PT/OT interventions was preceded by securing the ETT, removing unnecessary noninvasive devices, and disconnecting enteral feedings. Rehabilitation interventions were completed on 90% of patient days. One third of sessions involved intubated patients moving from bed to chair and standing, and 15% involved intubated patients ambulating. Therapy was stopped prematurely in only 4% of all sessions, mostly due to ventilator dysynchrony.Figure 1
illustrates a patient mechanically ventilated via an ETT ambulating with a physical therapist in the ICU
Femoral catheters are a perceived barrier to early rehabilitation due to risk of accidental
removal, bleeding or infection.29 However, a study observed 101 MICU patients with a femoral catheter (81% venous, 29% arterial, and 6% hemodialysis) who had 253 PT sessions over 210 ICU days. Patients were able to perform in-bed exercises, supine cycle ergometry, and stand or walk in 38%, 12%, and 23% of days, respectively. There were no catheter-related adverse events.69 Similar results were obtained by other studies.
Continuous Renal Replacement Therapy (CRRT)
The use of CRRT is another perceived barrier.21 However, a prospective single center
study including 57 consecutive patients (79% receiving mechanical ventilation) who received at least one PT session while undergoing CRRT demonstrated no safety events associated with CRRT.There was a total of 268 PT sessions that included in-bed exercises (29%), supine cycle ergometry (27%), sitting on edge of bed (30%), transferring to chair (5%), and standing or marching in place (9%). Similar results were obtained in another prospective study that also demonstrated potential improved CRRT filter life with patient mobilization.
Increased staffing and costs associated with early rehabilitation are commonly perceived
barriers. A controlled trial using a dedicated mobility team did not result in increased overall costs after accounting for extra costs related to the mobility team,39 with evidence of significantly decreased risk of readmission or death in the year after ICU dishcarge.74 Similarly, a QI project demonstrated a significant decrease in average MICU and hospital LOS.47 Using data from the QI project and other publications, a financial model for introducing ICU early mobilization and rehabilitation had 24 possible scenarios (ranging from conservative to best-case scenarios), 83% of which had net savings。
【方法】床上活动：病人在床上坐着或躺着的任何活动，例如：翻身、搭桥 、上肢负重训练(any activity undertaken whilst the patient is sitting or lying in bed such as rolling, bridging, upper-limb weight training)
下床活动：病人坐在床的边缘上的任何活动（腿垂到床边晃来晃去），站立，走路，在原地行走或坐在床外的椅子上。(any activity where the patient sits over the edge of the bed (dangling), stands, walks, marches on the spot or sits out of bed.)
【强度】运动的强度，应由病人的力量和耐力以及评估安全标准来决定。（The level of mobilization should be determined by the patient’s strength and endurance, as well as an assessment of the safety criteria.）
【时机评估】The safety criteria covered by the consensus group were divided into four categories: (1) respiratory considerations, including intubation status, ventilatory parameters and the need for adjunctive therapies; (2) cardiovascular considerations,including the presence of devices, cardiac arrhythmias and blood pressure; (3) neurological considerations, including level of consciousness, delirium and intracranial pressure, and (4) other considerations, including lines and surgical or medical conditions.
【评估方法】The consensus group agreed that a standard traffic-light system of recommendations would be used to assist clinicians in evaluating safety criteria, where red would indicate the need for caution as the risk of an adverse event, or consequences of an adverse event, was high, yellow would indicate that mobilization was possible, but only after further consideration and/or further discussion among the ICU multidisciplinary team, and green would indicate that the patient was safe to be mobilized (see Figure 1). It was agreed that the most conservatively scored parameter must take precedence over all other scores (for example, a single red would be sufficient to caution about the potential for high risk of an adverse event during mobilization, even if all other parameters were green).
Figure 1 Color coding definitions.
参考文献：Hashem MD, Parker AM, Needham DM, Early Mobilization and Rehabilitation of the Critically Ill Patient, CHEST (2016), doi: 10.1016/j.chest.2016.03.003.
Hodgson et al. Expert consensus and recommendations on safety criteria for active mobilization of mechanically ventilated critically ill adults Critical Care (2014) 18:658 DOI 10.1186/s13054-014-0658-y