Resp Care
-
Weaning comprises 40 percent of the duration of mechanical ventilation. Protocols to reduce weaning time and to identify candidates at the earliest possible moment have been introduced to reduce complications and costs. Increased demand for mechanical ventilation, an increase in the number of patients requiring prolonged ventilation, and resource/staffing issues have created an environment where automated weaning may play a role. ⋯ Preliminary research has demonstrated mixed results. Current systems continue to be evaluated in different patient populations and environments. Automated weaning is part of the ICU armamentarium, and identification of the patient populations most likely to benefit needs to be further defined.
-
Mechanical ventilation is a life-saving supportive therapy, but it can also cause lung injury, diaphragmatic dysfunction, and lung infection. Ventilator liberation should be attempted as soon as clinically indicated, to minimize morbidity and mortality. The most effective method of liberation follows a systematic approach that includes a daily assessment of weaning readiness, in conjunction with interruption of sedation infusions and spontaneous breathing trials. ⋯ Checklists can be used to reinforce application of the protocol, or possibly in lieu of one, particularly in environments where the caregiver-to-patient ratio is high and clinicians are well versed in and dedicated to applying evidence-based care. There is support for integrating best-evidence rules for weaning into the mechanical ventilator so that a substantial portion of the weaning process can be automated, which may be most effective in environments with low caregiver-to-patient ratios or those in which it is challenging to consistently apply evidence-based care. This paper reviews evidence for ventilator liberation protocols and discusses issues of implementation and ongoing monitoring.
-
Review
The ventilator liberation process: update on technique, timing, and termination of tracheostomy.
Tracheostomy is one of the most commonly performed procedures in the ICU. Despite the frequency of the procedure, there remains controversy regarding selection of patients who should undergo tracheostomy, the optimal technique, timing of placement and decannulation, as well as impact on outcome associated with the procedure. A growing body of literature demonstrates that percutaneous tracheostomy performed in the ICU is a safe procedure, even in high risk patients. ⋯ Although there was initial enthusiasm in support of early tracheostomy to improve patient outcomes, repeated studies have been unable to produce robust benefits. The question of optimal timing and location of decannulation has not been answered, but there is some reassurance that in aggregate, across a variety of ICUs, patients do not appear to be harmed by transfer to ward with tracheostomy. Future research into techniques, timing, and termination of tracheostomy is warranted.
-
A patient presented with shortness of breath and pleuritic pain shortly after bilateral knee synovial injections with sodium hyaluronate (HA). He was discharged after a brief hospitalization without a diagnosis when no Doppler or radiologic evidence of deep vein thrombosis or pulmonary emboli was found. Radiologic studies found patchy ground glass opacities that were predominantly peripheral in disposition, with prominent septal lines in the lungs; a subsequent pulmonary function test showed a reduced diffusing capacity of the lung for carbon monoxide (D(LCO)). These results prompted a lung biopsy that revealed multiple emboli composed of HA and fibrin in medium size pulmonary arteries, enlarged lymphatic vessels, and a bone marrow embolus. This is the first report of HA emboli following therapeutic HA injections and demonstrates that pulmonary function tests can be used to infer the reduction in pulmonary vascular area consequent to pulmonary emboli, and so can contribute to the detection of pulmonary emboli in unusual presentations.