Understanding Of Respiratory Physiology Research Articles

On the efficacy of facial masks to suppress the spreading of pathogen-carrying saliva particles during human respiratory events: Insights gained via high-fidelity numerical modeling.

Respiratory fluid dynamics is integral to comprehending the transmission of infectious diseases and the effectiveness of interventions such as face masks and social distancing. In this research, we present our recent studies that investigate respiratory particle transport via high-fidelity large eddy simulation coupled with the Lagrangian particle tracking method. Based on our numerical simulation results for human respiratory events with and without face masks, we demonstrate that facial masks could significantly suppress particle spreading. The studied respiratory events include coughing and normal breathing through mouth and nose. Using the Lagrangian particle tracking simulation results, we elucidated the transport pathways of saliva particles during inhalation and exhalation of breathing cycles, contributing to our understanding of respiratory physiology and potential disease transmission routes. Our findings underscore the importance of respiratory fluid dynamics research in informing public health strategies to reduce the spread of respiratory infections. Combining advanced mathematical modeling techniques with experimental data will help future research on airborne disease transmission dynamics and the effectiveness of preventive measures such as face masks.

Respiratory distress in small animals: Pathophysiology and clinical approach.

Respiratory distress is a common reason for animals to present to the emergency room. An understanding of respiratory physiology is helpful to facilitate accurate localization of the patient's source of respiratory distress. This knowledge will aid implementation of more appropriate therapies. Respiratory distress can occur secondary to lesions at any location of the respiratory system. Diseases affecting different portions of the respiratory track (eg, upper airway, lower airways, parenchymal, or the pleural space) lead to distinguishing clinical signs as the patient's respiratory physiology is affected differently. Respiratory distress can be life-threatening if it is not recognized and addressed in a timely matter. Prompt recognition of unique clinical signs may aid the clinician's ability to localize the disease process and implement targeted therapies. Diseases affecting different portions of the respiratory track (eg, upper airway, lower airways, parenchymal, or the pleural space) lead to distinguishing clinical signs as the patient's respiratory physiology is affected differently. Recognition of respiratory patterns allows clinicians to correlate clinical signs to the most likely affected region of the respiratory tract. Ideally, alveolar gas (ventilation) and blood flow (perfusion) are equally matched. However, even a normal lung does not have ideal ventilation/perfusion (V/Q) matching. There are a variety of conditions that lead to decreased lung compliance, from pathology of the pulmonary parenchyma (eg, pulmonary edema, alveolar infiltrates such as pneumonia or contusions, or pulmonary fibrosis), pleural space disease (eg, pneumothorax or pleural effusion), abdominal distension, or the inability to expand the rib cage (eg, pain, thoracic wall injury, constricting thoracic bandages). The five classic causes of hypoxemia include low FiO2 , diffusion impairment, hypoventilation, shunt, and V/Q mismatch. Being prepared to rapidly induce anesthesia and intubate dyspneic animals with upper airway obstruction may be required alleviate the risk of respiratory arrest.

Pre-hospital critical care management of severe hypoxemia in victims of Covid-19: a case series

ObjectiveDespite critical hypoxemia, Covid-19 patients may present without proportional signs of respiratory distress. We report three patients with critical respiratory failure due to Covid-19, in which all presented with severe hypoxemia refractory to supplemental oxygen therapy. We discuss possible strategies for ventilatory support in the emergency pre-hospital setting, and point out some pitfalls regarding the management of these patients. Guidelines for pre-hospital care of critically ill Covid-19 patients cannot be established based on the current evidence base, and we have to apply our understanding of respiratory physiology and mechanics in order to optimize respiratory support.MethodsThree cases with similar clinical presentation were identified within the Norwegian national helicopter emergency medical service (HEMS) system. The HEMS units are manned by a consultant anaesthesiologist.Patient’s next of kin and the Regional committee for medical and health research ethics approved the publication of this report.ConclusionPatients with Covid-19 and severe hypoxemia may pose a considerable challenge for the pre-hospital emergency medical services. Intubation may be associated with a high risk of complications in these patients and should be carried out with diligence when considered necessary. The following interventions are worth considering in Covid-19 patients with refractory hypoxemia before proceeding to intubation. First, administering oxygen via a tight fitting BVM with an oxygen flow rate that exceeds the patient’s ventilatory minute volume. Second, applying continuous positive airway pressure, while simultaneously maintaining a high FiO2. Finally, assuming the patient is cooperative, repositioning to prone position.

Clinical Scenarios of the Application of Electrical Impedance Tomography in Paediatric Intensive Care

EIT is a radiation-free functional modality that enables bedside imaging and monitoring of lung function and expansion. Clinical interest in this method has been driven by the need for bedside monitoring of the dynamics of the lungs and the effects of ventilatory manoeuvres, including changes in ventilator settings, suctioning, chest drains, positioning and physiotherapy. We aimed to describe the use of Electrical Impedance Tomography (EIT) as a clinical tool in a tertiary Paediatric Intensive Care unit. Children requiring intensive care with a variety of clinical conditions had an electrode belt with 16 electrodes wrapped around the chest, which sequentially applied a small alternating current from each electrode pair. The signal gives information on both real time, regional, global, and relative data. With the correct application, and understanding of the monitor, much clinical information can be gained, with potentially significant patient benefit. We present the clinical use of EIT in six conditions: Asthma, Ventilation weaning and expansion recoil, Sequential Lobar Collapse, Targeted Physiotherapy, Pleural Effusion assessment, and PEEP optimisation. Screenshots and analyses are offered displaying the pragmatic use of this technology. Electrical Impedance Tomography is a clinically useful tool on the Paediatric Intensive Care unit. It allows monitoring of a patient’s respiratory function in ways which are not possible through any other means. An understanding of respiratory physiology will allow use of this information to improve patient outcomes.

Mechanical ventilation in pediatrics: basic concepts

The use of pediatric mechanical ventilation involves inherent risks, and its application should be surrounded by specific care. In the operating room, anesthesia can produce different degrees of respiratory depression and the use of various ventilation modes is required. From a better understanding of respiratory physiology and the expansion of the knowledge about this subject, technological innovations have enabled a significant improvement in ventilatory assistance to pediatric patients. The purpose of this article is to review concepts on respiratory physiology of the child, the ventilation systems in pediatric anesthesia and ventilation modes often used in this group of patients – all these enable us to reduce the rate of complications related to mechanical ventilation.

Spirometry in children

Respiratory disorders are responsible for considerable morbidity and mortality in children. Spirometry is a useful investigation for diagnosing and monitoring a variety of paediatric respiratory diseases, but it is underused by primary care physicians and paediatricians treating children with respiratory disease. We now have a better understanding of respiratory physiology in children, and newer computerised spirometry equipment is available with updated regional reference values for the paediatric age group. This review evaluates the current literature for indications, test procedures, quality assessment, and interpretation of spirometry results in children. Spirometry may be useful for asthma, cystic fibrosis, congenital or acquired airway malformations and many other respiratory diseases in children. The technique for performing spirometry in children is crucial and is discussed in detail. Most children, including preschool children, can perform acceptable spirometry. Steps for interpreting spirometry results include identification of common errors during the test by applying acceptability and repeatability criteria and then comparing test parameters with reference standards. Spirometry results depict only the pattern of ventilation, which may be normal, obstructive, restrictive, or mixed. The diagnosis should be based on both clinical features and spirometry results. There is a need to encourage primary care physicians and paediatricians treating respiratory diseases in children to use spirometry after adequate training.

How to nurse the intensive care unit ventilator patient

Mechanical ventilators are an integral part of any intensive care unit. There are a variety of patients that may benefit from mechanical ventilation such as patients that are hypoxaemic (Pa02 <60mmHg) in spite of oxygen therapy, hypercapnic (PaC02>60mmHg) or at risk of impending respiratory failure. Mechanical ventilation is expensive and requires a dedicated nurse to care for the patient. This nurse must have an understanding of respiratory physiology, principles of mechanical ventilation, terminology, setting up the ventilator, troubleshooting problems, providing nursing care to meet the individual patient requirements and recognising signs of complications. Such cases require thorough clinical records and communication between staff members. They are labour intensive cases but can be extremely rewarding to nurse.

Frontiers in Respiratory Physiology - Grand Challenge

Frontiers in Respiratory Physiology - Grand Challenge

Monitoring ventilator weaning--predictors of success.

Improving the prediction of successful ventilator weaning and extubation is a goal that all Intensivists and perioperative physicians strive for. The successful wean and extubation of ventilated patients decreases hospital length of stay and associated costs, but more importantly it also reduces patient morbidity and mortality. This review evaluates traditional and novel indices used in the assessment for ventilatory wean readiness. Novel equipment such as the Bicore pulmonary monitor and the CO2 SMO Plus are now available on the market to assess and monitor ventilator weaning and may offer some value in this process. We also review the non-respiratory factors affecting weaning and the role of the bedside nurse and respiratory therapist. Resolution of the pulmonary compromise and an understanding of respiratory physiology, used in conjunction with monitored indices of weaning parameters in a consistent fashion will continue to improve our success rates of ventilator weaning and extubation.

Some Trends in the History of Sinus Surgery

Some trends in the American and Western European history and literature of sinus surgery for infection are summarized. Maxillary sinus surgery was first limited to drainage; subsequently radical surgery became very popular. With modern antibiotics and antiallergic management and better understanding of respiratory physiology, the indications for radical surgery have been reduced. The dangers of ethmoid surgery have been recognized for a long time. The popularity of the frontal osteoplastic operation is due to the poor results of the other techniques. The introduction of the Hopkins scopes and the functional concept in sinus surgery allow an increasingly popular conservative surgical approach to sinus infection.

Ventilatory Management in the Critically Ill

A basic understanding of respiratory physiology and ventilator-patient interaction is critical for the initiation of ventilatory support and management of the ventilated patient. A brief review of these subjects is incorporated in this outline of the approach to the patient requiring mechanical ventilation.

Pathogenesis and treatment of adult respiratory distress syndrome

As the scope of oral and maxillofacial surgery broadens, the oral and maxillofacial surgeon is more often faced with critically ill patients. These patients frequently have cardiopulmonary instability and may be nutritionally and immunologically compromised. Following initial resuscitation or detailed surgical procedures, such critically ill patients are known to be at high risk of developing post-insult pulmonary insufficiency. A detailed knowledge and understanding of respiratory physiology and the pathogenesis of respiratory failure are essential for the proper diagnosis and management of these patients. In reviewing the oral and maxillofacial surgery literature, there are only a few publications and discussions on this important subject. 1–3 In this review we shall discuss the history, etiology, pathophysiology, and current treatment concepts of adult respiratory distress syndrome (ARDS).

The surgery for pulmonary tuberculosis.

The surgery for pulmonary tuberculosis.

Chest trauma. Analysis of 685 patients.

ADVANCES in the care of traumatic injuries have often coincided with wars where large numbers of casualties are concentrated in both time and space. In civilian practice, injuries tend to be more widely distributed and advances in management come more slowly and spread less quickly. Patterns and trends of injury are difficult to recognize and therapy is often based on incomplete or misunderstood evidence. Progress in the understanding of respiratory physiology and mechanics has radically changed the concepts of management of chest injury. 1-3 At the same time, the general use of the automobile has increased the frequency with which chest trauma is seen in civilian practice. How this affects the overall pattern of chest injury is unknown. This retrospective study was undertaken to determine the extent and pattern of chest injury in a 16-year period at one hospital. Methods The records of all chest injury patients admitted to Colorado

Rehabilitation of a patient with a high cervical cord lesion; report of a case.

There is no more difficult problem in rehabilitation than that of a patient with a high section of the cervical cord. Patients with physiologically and/or anatomically complete cervical cord lesions above the fourth cervical vertebra do not survive without artificial respiration. Survival of patients with complete lesions between the fourth and fifth cervical vertebrae is becoming more frequent with present-day supportive therapy and a better understanding of respiratory physiology. The following case history demonstrates rehabilitation to maximal self-sufficiency in a patient with a physiologically complete lesion between the fourth and fifth cervical vertebrae. REPORT OF A CASE On July 6, 1952, the patient, a 15-year-old boy, dived into shallow water; immediate motor and sensory loss of his trunk and all four extremities resulted. During the following four to six hours, the patient had intermittent periods of unconsciousness and respiratory difficulty. Roentgenograms taken within two hours after the accident revealed normal

Treatment of penetrating and perforating chest wounds: A discussion of its complication, the organized hemothorax

1. 1. There has been a marked improvement in the treatment of the acute chest wound based on a better understanding of respiratory physiology. 2. 2. Although the principles of treatment and their application are based on experience gained under conditions of warfare, it is believed that they can be applied profitably to the civilian casualty. 3. 3. The importance of establishing stable respiratory function before operation is pointed out. The methods at hand for accomplishing this stabilization are described. 4. 4. The implications of fluid replacement therapy in the chest casualty are discussed. 5. 5. The indications for thoracotomy in wounds of the chest are presented. 6. 6. The complication of organized hemothorax is discussed and its treatment described.