concurrent trigger sensitivity adjustment and diaphragmatic facilitation on weaning from mechanical ventilation

Conditions: Acute Respiratory Failure; Mechanically Ventilated Patients

Summary: as acute respiratory failure (arf) is a challenging serious condition especially when it necessitates intubation to deliver mechanical ventilation which is a fundamental strategy for supporting the respiratory function when the patient can't bear all work of breathing. even if it represents a life-saving procedure, mechanical ventilation (mv) is associated to life-threatening complications as respiratory muscle dysfunction, and atrophy that lead to long stay in intensive care unit (icu) and higher mortality. weaning difficulty is experienced in nearly 30 percent of critically ill patients. the decision to extubate mechanically ventilated patients should be aimed at preventing both the risk of premature liberation from mv which is associated with poor outcome and the risk of delayed extubation which increases the complications of prolonged mv and there is increasing evidence that mv itself may adversely affect the diaphragm's structure and function, which has been termed ventilator-induced diaphragmatic dysfunction (vidd). the combination of positive pressure ventilation and positive end-expiratory pressure may unload the diaphragm which leads to changes in myofibril length and rapid atrophy that occurs within hours of mv, caused by an imbalance between protein synthesis and proteolysis, lead to a large reduction in the inspiratory pressure generated by the diaphragm.

physiotherapist is a key member of multidisciplinary team and plays an vital role in icu in improving the patient's quality of life, inspiratory muscle training (imt) applies a load to the diaphragm and accessory inspiratory muscles to increase their strength and endurance. adjustment of ventilator sensitivity provides resistance and hence a pressure load to the inspiratory muscles, and proprioceptive neuromuscular facilitation (pnf) of respiration is newly introduced in icu for patients who are ventilator dependent by use of external proprioceptive and tactile stimuli to assist respiration. pnf techniques improve inspiration and expiration in next cycle that shows improvement with active initiation or more participation in respiration to alter the rate and depth of breathing, facilitate respiratory muscles, improve breathing pattern and increase tidal volume so the purpose of this study is to determine the concurrent effect of trigger sensitivity adjustment and diaphragmatic facilitation on weaning of patients from mechanical ventilation. as the patients may gain a more benefit from the combination of trigger sensitivity adjustment and manual diaphragmatic facilitation (pnf) techniques than from each one alone. therefore, a concurrent trigger sensitivity adjustment and manual diaphragmatic facilitation (pnf) techniques must likely be started within 24 to 48 hours of initiating mv to protect diaphragm from atrophy, facilitate faster weaning, minimize icu stay and cost of treatment, and decrease the morbidity and mortality rate of those patients admitted to icu. study hypothesis: it will be hypothesized that there is no effect of diaphragmatic facilitation on weaning of patients from mechanical ventilation. it will be hypothesized that there is no effect of trigger sensitivity adjustment on weaning of patients from mechanical ventilation. it will be hypothesized that there is no effect of a concurrent trigger sensitivity adjustment and diaphragmatic facilitation on weaning of patients from mechanical ventilation.

Eligibility criteria:
inclusion criteria: * patients of both sexes with age ranges (50-60) years old. * patients will be referred with acute respiratory failure (arf) inside icu. * all patients are intubated and mechanically ventilated with assisted control (pressure or volume) or pressure support modes for 24-48 hours. * all patients with positive end expiratory pressure (peep) don't exceed 10 cmh2o. * all patients are hemodynamically stable; temperature (36.2-37.5) c, heart rate \ 90% * all patients are conscious and responsive to verbal command. exclusion criteria: * fraction of inspired oxygen (fio2)\>0.6 and spo2 \< 85% to avoid further hypoxia and respiratory distress. * positive end expiratory pressure (peep) \> 10 cmh2o to avoid barotrauma. * severe pulmonary condition; acute pulmonary embolism, undrained pneumothorax. * unstable hemodynamic condition as defined by heart rate more than 140 beats/min, systolic blood pressure \>180 mmhg or low blood pressure \< 80 mmhg and respiratory rate is exceeding 35 breaths/min. * patients who develop any cardiac condition during the course of treatment; acute myocardial infarction or cardiac arrhythmia. * patients who recently have undergo cardiac or abdominal or gynecological surgery. * active lung infection like tuberculosis. * chest trauma such as rib fracture, flail chest, thoracic vertebra fracture or chest burns. * spinal cord injuries involved the phrenic nerve. * active bleeding as alveolar hemorrhage, hemoptysis. * heavy sedation that depresses respiratory drive or ability to follow commands.

Keywords: acute respiratory failure mechanical ventilation ventilator induced diaphragmatic dysfunction proprioceptive neuromuscular training diaphragmatic facilitation diaphragmatic pnf inspiratory muscle training trigger sensitivity