Resting Physiologic Dead Space as Predictor of Postoperative Pulmonary Complications After Robotic-Assisted Lung Resection: A Pilot Study.

Lung resection surgery carries significant risks of postoperative pulmonary complications (PPC). Cardiopulmonary exercise testing (CPET) is performed to predict risk of PPC in patients with severely reduced predicted postoperative forced expiratory volume in one second (FEV1) and diffusion of carbon monoxide (DLCO). Recently, resting end-tidal partial pressure of carbon dioxide (PETCO) has been shown as a good predictor for increased risk of PPC.

Noninvasive ventilation: education and training. A narrative analysis and an international consensus document.

Noninvasive ventilation (NIV) is an increasingly used method of respiratory support. The use of NIV is expanding over the time and if properly applied, it can save patients' lives and improve long-term prognosis. However, both knowledge and skills of its proper use as life support are paramount.

Teflon Injection into the Trachea Causes Predictable Fibroblastic Response and Collagen Deposition: A Pilot Study.

Background: Expiratory central airway collapse is an increasingly recognized abnormality of the central airways and may be present in as many as 22% of patients evaluated for chronic obstructive pulmonary disease and/or asthma. Many current treatment options require invasive procedures that have been shown to cause significant morbidity and mortality. To test the hypothesis that Teflon injection will induce sufficient fibroblast proliferation and collagen deposition, we evaluated the time course on the effect of Teflon injection in the posterior membranous trachea on the histopathology of the tracheobronchial tree.

Timing Matters: Circadian Rhythm in Sepsis, Obstructive Lung Disease, Obstructive Sleep Apnea, and Cancer.

Physiological and cellular functions operate in a 24-hour cyclical pattern orchestrated by an endogenous process known as the circadian rhythm. Circadian rhythms represent intrinsic oscillations of biological functions that allow for adaptation to cyclic environmental changes. Key clock genes that affect the persistence and periodicity of circadian rhythms include BMAL1/CLOCK, Period 1, Period 2, and Cryptochrome.

Inhibition of Intestinal Thiamin Transport in Rat Model of Sepsis.

Objectives: Thiamin deficiency is highly prevalent in patients with sepsis, but the mechanism by which sepsis induces thiamin deficiency is unknown. This study aimed to determine the influence of various severity of sepsis on carrier-mediated intestinal thiamin uptake, level of expressions of thiamin transporters (thiamin transporter-1 and thiamin transporter-2), and mitochondrial thiamin pyrophosphate transporter.

Design: Randomized controlled study.

Positive end-expiratory airway pressure does not aggravate ventilator-induced diaphragmatic dysfunction in rabbits.

Introduction: Immobilization of hindlimb muscles in a shortened position results in an accelerated rate of inactivity-induced muscle atrophy and contractile dysfunction. Similarly, prolonged controlled mechanical ventilation (CMV) results in diaphragm inactivity and induces diaphragm muscle atrophy and contractile dysfunction. Further, the application of positive end-expiratory airway pressure (PEEP) during mechanical ventilation would result in shortened diaphragm muscle fibers throughout the respiratory cycle.

Successful closure of bronchopleural fistula with Xeroform dressing.

Bronchopleural fistula (BPF) is a communication between the pleural space and the bronchial tree, and is associated with significant morbidity and mortality. Treatment options for BPF include surgical closure and medical therapy. In an unstable patient, invasive surgical intervention is not an option.

Triggering of the ventilator in patient-ventilator interactions.

With current ventilator triggering design, in initiating ventilator breaths patient effort is only a small fraction of the total effort expended to overcome the inspiratory load. Similarly, advances in ventilator pressure or flow delivery and inspiratory flow termination improve patient effort or inspiratory muscle work during mechanical ventilation. Yet refinements in ventilator design do not necessarily allow optimal patient-ventilator interactions, as the clinician is key in managing patient factors and selecting appropriate ventilator factors to maintain patient-ventilator synchrony.

Interactive effects of corticosteroid and mechanical ventilation on diaphragm muscle function.

Information on the interactive effects of methylprednisolone, controlled mechanical ventilation (CMV), and assisted mechanical ventilation (AMV) on diaphragm function is sparse. Sedated rabbits received 2 days of CMV, AMV, and spontaneous breathing (SB), with either methylprednisolone (MP; 60 mg/kg/day intravenously) or saline. There was also a control group.

Bench-to-bedside review: Diaphragm muscle function in disuse and acute high-dose corticosteroid treatment.

Critically ill patients may require mechanical ventilatory support and short-term high-dose corticosteroid to treat some specific underlying disease processes. Diaphragm muscle inactivity induced by controlled mechanical ventilation produces dramatic alterations in diaphragm muscle structure and significant losses in function. Although the exact mechanisms responsible for losses in diaphragm muscle function are still unknown, recent studies have highlighted the importance of proteolysis and oxidative stress.

Acute effects of high-dose methylprednisolone on diaphragm muscle function.

The time- and dose-dependent effects of acute high-dose corticosteroids on the diaphragm muscle are poorly defined. This study aimed to examine in rabbits the temporal relationships and dose-response effects of acute high-dose methylprednisolone succinate on diaphragmatic contractile and structural properties. Animals were assigned to groups receiving: (1) 80 mg/kg/day methylprednisolone (MP80) intramuscularly for 1, 2, and 3 days; (2) 10 mg/kg/day methylprednisolone (MP10, pulse-dose) for 3 days; or (3) saline (placebo) for 3 days; and (4) a control group.

Optimal arrangement of magnetic coils for functional magnetic stimulation of the inspiratory muscles in dogs.

In an attempt to maximize inspiratory pressure and volume, the optimal position of a single or of dual magnetic coils during functional magnetic stimulation (FMS) of the inspiratory muscles was evaluated in twenty-three dogs. Unilateral phrenic magnetic stimulation (UPMS) or bilateral phrenic magnetic stimulation (BPMS), posterior cervical magnetic stimulation (PCMS), anterior cervical magnetic stimulation (ACMS) as well as a combination of PCMS and ACMS were performed. Trans-diaphragmatic pressure (Pdi), flow, and lung volume changes with an open airway were measured.

Potential advantages of patient-ventilator synchrony.

During conventional mechanical ventilation, fixed set pressure, flow, and tidal volume result in a mismatch between patient and ventilator inspiratory time and in a patient's inability to adapt to changing ventilatory demand. Synchrony between the patient and ventilator improves neuromuscular coupling and the ability to adapt to increased ventilatory demand or loading. The sensation of dyspnea prevents ineffective inspiratory efforts and attenuates periodic breathing during sleep.

Early effects of mechanical ventilation on isotonic contractile properties and MAF-box gene expression in the diaphragm.

This study aimed to determine the time-dependent effects of diaphragmatic inactivity on its maximum shortening velocity (V(max)) and the muscle atrophy F-box (MAF-box, atrogin-1) gene expression during controlled mechanical ventilation (CMV). Twenty-four New Zealand White rabbits were grouped into 1 day, 2 days, and 3 days of CMV and controls in equal numbers. The in vitro isotonic contractile properties of the diaphragm were determined.

Assist-control mechanical ventilation attenuates ventilator-induced diaphragmatic dysfunction.

Controlled mechanical ventilation induced a profound diaphragm muscle dysfunction and atrophy. The effects of diaphragmatic contractions with assisted mechanical ventilation on diaphragmatic isometric, isotonic contractile properties, or the expression of muscle atrophy factor-box (MAF-box), the gene responsible for muscle atrophy, are unknown. We hypothesize that assisted mechanical ventilation will preserve diaphragmatic force and prevent overexpression of MAF-box.