Acupuncture is a treatment intervention used globally for a wide variety of disorders. Its efficacy has been established over the course of 3000 years, originating in Asia and diversifying worldwide.The scientific basis for acupuncture remains unclear. Nonetheless, acupuncture releases neurochemical substrates, such as endorphins, serotonin, and norepinephrine.Acupuncture is considered to be a safe treatment when applied by a certified acupuncturist.Acupuncture has already been deployed in the treatment of sepsis or muscle weakness.Studies have revealed that acupuncture significantly improved grip strength and respiratory muscle strength in chronic obstructive pulmonary disease participates.Neuromuscular electrical stimulation (NMES) is an alternative to mobilize and exercise because it does not require active patient participation and can be used on bedridden patients.The investigators designed a study to compare the effects of acupuncture, electroacupuncture, and neuromuscular electrical stimulation on mechanical ventilation patients with weaning difficulties

Inclusion Criteria:

• Prolonged mechanical ventilation duration (>72 h)
• stable oxygen saturation, fraction of inspired oxygen≤55%, and positive end expiratory pressure (PEEP)≤8 cmH2O
• dose of dopamine<10 μg/kg/min and dose of epinephrine<0.4 μg/kg/min;
• mean arterial pressure>75 mmHg and urine output>1 mL/kg/h
• good healing of the incision after surgery;
• normal cognitive function
• no history of chronic mental illness or chronic obstructive pulmonary disease

Exclusion Criteria:

• Inability to perform physical activities
• long-term MV prior to admission
• neurological comorbidities involving muscles
• irreversible disorders with a 6-month mortality rate of>50% according to Acute Physiology and Chronic Health Evaluation II (APACHEII)
• unsound limbs or unstable fractures
• administration of glucocorticoids (prednisone or other corticosteroid dose equivalents>20 mg/day) for at least 20 days prior to admission
• cardiopulmonary resuscitation before admission to the ICU
• radiotherapy or chemotherapy within the previous 6 months
• presence of comorbidities, including acute myocarditis, deep venous thrombosis/embolism, and cerebrovascular accident
• Patients with implanted pacemakers or defibrillators
• Pregnancy and lactation patients
• Patients with active bleeding or bleeding tendency
• Skin infection or injury at the acupuncture site