Diaphragm Injury

Unrecognized abdominal and pelvic injuries can result in catastrophic disability and death. Sporadic reports of "occult" injuries have generated concern, and physicians, fearing that they may miss such an injury, have adopted the practice of obtaining computed tomography on virtually all patients with significant blunt trauma. This practice exposes large numbers patients to dangerous radiation at considerable expense, while detecting injuries in a small minority of cases. Existing data suggest that a limited number of criteria can reliably identify blunt injury victims who have "no risk" of abdominal or pelvic injuries, and hence no need for computed tomography (CT), without misidentifying any injured patient. It is estimated that nationwide implementation of such criteria could result in an annual reduction in radiographic charges of $75 million, and a significant decrease in radiation exposure and radiation induced malignancies. This study seeks to determine whether "low risk" criteria can reliably identify patients who have sustained significant abdominal or pelvic injuries and safely decrease CT imaging of blunt trauma patients. This goal will be accomplished in the following manner: All blunt trauma victims undergoing computed tomography of the abdomen/pelvis in the emergency department will undergo routine clinical evaluations prior to radiographic imaging. Based on these examinations, the presence or absence of specific clinical findings (i.e. abdominal/pelvic/flank pain, abdominal/pelvic/flank tenderness, bruising abrasions, distention, hip pain, hematuria, hypotension, tachycardia, low or falling hematocrit, intoxication, altered sensorium, distracting injury, positive FAST imaging, dangerous mechanism, abnormal x-ray imaging) will be recorded for each patient, as will the presence or absence of abdominal or pelvic injuries. The clinical findings will serve as potential imaging criteria. At the completion of the derivation portion of the study the criteria will be examined to find a subset that predicts injury with high sensitivity, while simultaneously excluding injury, and hence the need for imaging, in the remaining patients. These criteria will then be confirmed in a separate validation phase of the study. The criteria will be considered to be reliable if the lower statistical confidence limit for the measured sensitivity exceeds 98.0%. Potential reductions in CT imaging will be estimated by determining the proportion of "low-risk" patients that do not have significant abdominal or pelvic injuries.

Mechanical ventilation can lead to diaphragm and lung injury. During mechanical ventilation, the diaphragm could be completely rested or it could be overworked, either of which may cause diaphragm injury. Mechanical stress and strain applied by mechanical ventilation or by the patient's own respiratory muscles can also cause injury to the lungs. Diaphragm and lung injury are associated with increased morbidity and mortality. Throughflow is a novel system that can reduce dead space without the need to increase the tidal ventilation, reducing the ventilatory demands and respiratory drive.

This study is designed to characterize the changes in diaphragm structure, function and biology during bridging to lung transplant by mechanical ventilation or extracorporeal life support.

We intend, with this study, to prove that blocking the molecular mechanisms whose blockade prevents VIDD in animals, will indeed prevent the development of VIDD in humans as well. We believe that this evidence will serve as the required basis for proceeding with large, ICU-based clinical trial(s) of a drug to prevent VIDD.

Reduced diaphragmatic activity during mechanical ventilation can lead to diaphragmatic disuse atrophy, atelectasis, increased lung stress and strain, and hemodynamic impairment. This, in turn, may prolong the duration of mechanical ventilation, make weaning more difficult, and even increase mortality. Synchronizing phrenic nerve stimulation to promote diaphragmatic activity may prevent ventilator-induced lung injury and ventilator-induced diaphragm dysfunction, thereby improving patient outcomes. Surgically implanted phrenic nerve stimulation has been used in certain neurological disorders, but the effects of percutaneous non-invasive synchronized phrenic nerve stimulation in patients with ARDS undergoing mechanical ventilation remain unclear and require further investigation.

This study is a prospective physiologic study. The primary study population will be adult invasive tracheal intubated patients with COPD, and investigators will collect relevant demographic data, vital signs, and baseline physiologic parameters of the patients prior to the spontaneous breathing test（SBT). The participants will be divided into a successful withdrawal group and a failed withdrawal group according to the SBT outcome, and the changes in the above parameters during SBT will be compared between the two groups .

Air is normally pumped in and out of the lungs by the muscles that contribute to inhalation and exhalation, called the respiratory muscles. The abdominal muscles help by forcing air out of your lungs during exhalation; whereas the diaphragm, the main muscle used for breathing, contracts to get air into the lungs during inhalation. With mechanical ventilation, respiratory muscles are able to rest and recover while the breathing machine takes over; however, this may cause respiratory muscle weakness. Patients who develop weakness of these muscles may require more assistance from the ventilator and take longer to recover their ability to breathe without assistance. The impact of this phenomenon on long-term outcomes is uncertain. The RESPIRE study is designed to characterize how respiratory muscles change during mechanical ventilation and to evaluate the impact on long term quality of life. An additional objective of this study is to examine novel measures obtained from automated functions of a ventilator, that may better predict success from weaning from mechanical ventilation.