Use and nursing of the helmet in delivering non invasive ventilation.

Continuous positive end-expiratory pressure (CPAP) and Pressure Support Ventilation (PSV) are commonly used for the therapy of several forms of respiratory failure. CPAP and PSV can be delivered both during invasive respiratory treatment, by means of an endotracheal tube or tracheostomy, and during non invasive respiratory treatment. Non Invasive Ventilation (NIV) is commonly used for the therapy of several forms of respiratory failure (COPD, Weaning period from Invasive Mechanical Ventilation, Cardiogenic Edema,.) and the helmet could be a good new device to deliver it with a better compliance instead the common facial mask without increasing the nurses' workload.

The abdominal compartment syndrome. Clinical relevance.

Increased intra-abdominal pressure (IAP) may occur in a number of different situations encountered by intensivists, such as tense ascites, abdominal hemorrhage, use of military antishock trousers, abdominal obstruction, during laparoscopy, large abdominal tumors and peritoneal dialysis.1-3 Both clinical and experimental evidence indicate that increased IAP may adversely affect cardiac, renal, respiratory and metabolic functions.1-5 Despite this, increased IAP is rarely recognized and treated in Intensive Care Unit (ICU) settings. There appears to be two reasons for this: the physiologic consequences of increased IAP are not well know, to most physicians and, more importantly, the capability of easily measuring IAP has not been well documented. In this chapter, we will discuss: 1) the different methods proposed to evaluate IAP in ICU; 2) the physiopathological consequences of increased IAP; 3) the existing clinical data about IAP in critically ill patients. Considering overall our data, we can conclude that: 1) different techniques are available at the bedside to estimate the IAP; 2) the IAP ranges between 10 and 20 cmH2O, substantially increased compared to normal subjects. Most of the patients have IAH, while few of them (<5%) present clinical characteristics of ACS; 3) the IAP is different among different categories of patients and its increase is not limited to surgical patients only; 4) the increase in IAP appears to influence respiratory function, homodynamic, kidney, gut and brain physiology; 5) the IAP seems to be correlated with severity scores but its relation to mortality is controversial; 6) the routine measurements of IAP by means of bladder pressure are not associated with an increased rate of urinary tract infections.

Respiratory mechanics in brain injured patients.

BACKGROUND: Brain injured patients have an increased risk of extracerebral organ failure, mainly pulmonary dysfunction. The prevalent cause of pulmonary failure is ventilator associated pneumonia (VAP) which increases morbidity and mortality. The respiratory dysfunction is mainly characterized by the presence of alveolar consolidation of the dependent lobes. METHODS: We investigated the mechanical changes of the respiratory system and the effects of positive end-expiratory pressure (PEEP) in 10 normal subjects, in 10 brain injured patients without respiratory failure and in 10 brain injured patients with respiratory failure (PaO2/FiO2 lower than 200 mmHg) due to VAP. RESULTS: We found that: 1) Intra-Abdominal Pressure (IAP) was increased in brain injured patients with or without respiratory failure compared to normal subjects; 2) the Elastance of respiratory system (Est,rs), the Elastance of the chest wall (Est,cw) and Resistance max of the Lung (Rmax,L) increased in brain injured patients independently from the presence of respiratory failure; 3) in brain injured patients with respiratory failure application of 15 cmH2O of PEEP increased the Elastance of the Lung (Est,L), Est,rs and Rmax,L, while did not result in significant alveolar recruitment and oxygenation improvement. CONCLUSIONS: In conclusion, in brain injured patients 1) the respiratory mechanics is altered; 2) PEEP is uneffective to improve respiratory function in respiratory failure due to ventilator associated pneumonia. Further studies are warranted to better elucidate the pathophysiology and clinical management of respiratory dysfunction in brain injured patients.

[Mechanical ventilation in acute respiratory distress syndrome. New Trends]. / La ventilazione meccanica nella sindrome da distress respiratorio acuto. Nuovi orientamenti.

Adult Respiratory Distress Syndrome (ARDS) is characterized by an inflammatory process affecting endothelial and epithelial lung tissue, with occurrence of hypoxemia, bilateral X-ray infiltrates, in absence of cardiogenic edema. The introduction of Computerized Tomography brought some improvements in understanding the ARDS lung, leading to a pulmonary model made up of three zones: 1) normally inflated, 2) recruitable and 3) consolidated. It has now been well established that mechanical ventilation of ARDS lung presents some iatrogenic effects that may affect mortality. Several mechanisms are considered responsible of ventilator-associated lung injury (VALI): high inspired oxygen fraction, high inspiratory plateau pressure and large tidal volume, and intratidal collapse and reinflation of alveolar units. In these years, different ventilatory strategies in the treatment of ARDS patients have been suggested to decrease and to prevent VALI. The most important one seems to be the application of an appropriate value of tidal volume and positive end-expiratory pressure (PEEP). Several randomized studies, which compared low versus high tidal volumes, have recently been finished. Despite some differences, it seems that a ventilatory management limiting inspiratory plateau pressure to 35 cmH2O or lower may be useful to reduce VALI and mortality, also in association with a PEEP level sufficient to decrease the end-expiratory collapse. Another useful ventilatory tool for improving gas exchange and decreasing VALI in ARDS patients is likely the prone positioning, even if further studies are necessary to understand how this maneuver may really affect mortality. Another therapeutic instrument for improving oxygenation in ARDS patients is the inhalation of NO. Unfortunately, this pharmacological agent does not seem to affect the outcome of these patients.