PubMed Health⌕ Search

Biomedical subjects

Paolo Navalesi

Publications and source records attributed to Paolo Navalesi.

15 recordsLinked to original sources
PubMed2006

Non-invasive ventilation in chronic obstructive pulmonary disease patients: helmet versus facial mask.

RATIONALE: The helmet is a new interface with the potential of increasing the success rate of non-invasive ventilation by improving tolerance. OBJECTIVES: To perform a physiological comparison between the helmet and the conventional facial mask in delivering non-invasive ventilation in hypercapnic patients with chronic obstructive pulmonary disease. METHODS: Prospective, controlled, randomized study with cross-over design. In 10 patients we evaluated gas exchange, inspiratory effort, patient-ventilator synchrony and patient tolerance after 30 min of non-invasive ventilation delivered either by helmet or facial mask; both trials were preceded by periods of spontaneous unassisted breathing. MEASUREMENTS: Arterial blood gases, inspiratory effort, duration of diaphragm contraction and ventilator assistance, effort-to-support delays (at the beginning and at the end of inspiration), number of ineffective efforts, and patient comfort. MAIN RESULTS: Non-invasive ventilation improved gas exchange (p<0.05) and inspiratory effort (p<0.01) with both interfaces. The helmet, however, was less efficient than the mask in reducing inspiratory effort (p<0.05) and worsened the patient-ventilator synchrony, as indicated by the longer delays to trigger on (p<0.05) and cycle off (p<0.05) the mechanical assistance and by the number of ineffective efforts (p<0.005). Patient comfort was no different with the two interfaces. CONCLUSIONS: Helmet and facial mask were equally tolerated and both were effective in ameliorating gas exchange and decreasing inspiratory effort. The helmet, however, was less efficient in decreasing inspiratory effort and worsened the patient-ventilator interaction.

Aged↗
PubMed2006

Physiological responses during a T-piece weaning trial with a deflated tube.

RATIONALE: T-piece trials and spontaneous breathing trials through the tracheostomy tube are often used as weaning techniques. They are usually performed with the cuff inflated, which may increase the inspiratory load and/or influence the tidal volume generated by the patient. We assessed diaphragmatic effort during T-piece trials with or without cuff inflation. SETTINGS: Respiratory intensive care unit METHODS: We measured breathing pattern, transdiaphragmatic pressure (Pdi), the pressure-time product of the diaphragm, per minute (PTPdi/min) and per breath (PTPdi/b), and lung mechanics (lung compliance and resistance) in 13 tracheotomized patients ready for a weaning trial. V(T) was recorded with respiratory inductive plethysmography (RIP-V(T)) or pneumotachography PT-V(T)). Patients completed two T-piece trials of 30[Symbol: see text]min each with or without the cuff inflated. RESULTS: RIP-V(T) and PT-V(T) values were similar with the cuff inflated, but PT-V(T) significantly underestimated RIP-V(T) when the cuff was deflated, and therefore the RIP-V(T) was chosen as the reference method. The RIP-V(T) was significantly greater and the Pdi and PTPdi/min significantly lower when the cuff was deflated than when it was inflated. The efficiency of the diaphragm, calculated by the ratio of PTPdi/b over RIP-V(T), was also improved, while no changes were observed in lung mechanics. CONCLUSIONS: Diaphragmatic effort is significantly lower during a T-piece trial with a deflated cuff than when the cuff is inflated, while RIP-V(T) is higher, so that the diaphragm's efficiency in generating tidal volume is also improved.

Aged↗
PubMed2006

Time of non-invasive ventilation.

Non-invasive ventilation (NIV) is a safe, versatile and effective technique that can avert side effects and complications associated with endotracheal intubation. The success of NIV relies on several factors, including the type and severity of acute respiratory failure, the underlying disease, the location of treatment, and the experience of the team. The time factor is also important. NIV is primarily used to avert the need for endotracheal intubation in patients with early-stage acute respiratory failure and post-extubation respiratory failure. It can also be used as an alternative to invasive ventilation at a more advanced stage of acute respiratory failure or to facilitate the process of weaning from mechanical ventilation. NIV has been used to prevent development of acute respiratory failure or post-extubation respiratory failure. The number of days of NIV and hours of daily use differ, depending on the severity and course of the acute respiratory failure and the timing of application. In this review article, we analyse, compare and discuss the results of studies in which NIV was applied at various times during the evolution of acute respiratory failure.

Humans↗
PubMed2006

Transtracheal open ventilation in acute respiratory failure secondary to severe chronic obstructive pulmonary disease exacerbation.

RATIONALE: Patients who fail noninvasive ventilation are generally intubated and are then subjected to complications of invasive mechanical ventilation. With transtracheal open ventilation, ventilator support is delivered through an uncuffed small bore minitracheostomy tube, which eliminates pooling of secretions above the cuff and thus reduces the risk of tracheobronchial microbial colonization. OBJECTIVE: To compare transtracheal open ventilation (treatment group) with conventional invasive ventilation (control group) in patients with exacerbation of chronic obstructive pulmonary disease who initially failed noninvasive ventilation. METHODS: Patients were randomized to receive trans-tracheal open ventilation (n=19) or conventional invasive ventilation (n=20). MEASUREMENTS AND MAIN RESULTS: There was no difference in arterial blood gases after 1 and 30 h between the two groups. Two patients receiving transtracheal open ventilation and 13 undergoing conventional ventilation had complications (p<0.0001). Compared with conventional ventilation, transtracheal open ventilation significantly decreased both the duration of mechanical ventilation (7.6+/-4.7 vs. 18.6+/-10.6 d, p<0.0001) and length of stay in the intensive care unit (10.2+/-4.5 vs. 21.3+/-9.7 d, p<0.0001). CONCLUSIONS: Transtracheal open ventilation was as effective as conventional ventilation in maintaining adequate gas exchange and reducing complications, duration of mechanical ventilation, and intensive care unit length of stay.

Acute Disease↗
PubMed2005

Physiologic comparison between conventional mechanical ventilation and transtracheal open ventilation in acute traumatic quadriplegic patients.

OBJECTIVE: To evaluate the efficacy of mechanical ventilation administered through a small-bore, uncuffed tracheotomy tube, so-called transtracheal open ventilation (TOV), in comparison with conventional mechanical ventilation via a cuffed tracheal tube (endotracheal invasive ventilation, EIV). DESIGN: Physiologic study. SETTING: Intensive care unit of a referral trauma center. PATIENTS: Ten acute quadriplegic patients. INTERVENTIONS: In acute quadriplegic patients receiving EIV, TOV was subsequently applied via an uncuffed, small-bore tube (internal diameter of 4 or 5 mm). MEASUREMENTS AND MAIN RESULTS: Compared with EIV, arterial blood gases were not significantly different after 1 hr of TOV (Pao2/Fio2, 222.8 +/- 60.9 vs. 218.5 +/- 60.3; Paco2, 37.8 +/- 7.1 torr [5.04 +/- 0.95 kPa] vs. 35.5 +/- 6.8 torr [4.73 +/- 0.91 kPa], for EIV and TOV, respectively). Respiratory rate (19.5 +/- 4.7 vs. 19.6 +/- 5 breaths/min) and inspiratory effort (pressure-time product of esophageal pressure during a 1-min period, 125.9 +/- 48.4 vs. 112.8 +/- 36.4 cm H2O.sec.min) were also no different between the two modes. After 24 hrs of TOV, compared with EIV and TOV after 1 hr, respiratory rate and arterial blood gases remained stable, and the pressure-time product of esophageal pressure during a 1-min period was slightly, but significantly, reduced (83.5 +/- 16.6 cm H2O.sec.min, p < .05). CONCLUSIONS: In acute quadriplegic patients receiving mechanical ventilation, TOV was as effective as EIV in providing ventilatory support.

Adult↗
PubMed2005

Noninvasive ventilation to prevent respiratory failure after extubation in high-risk patients.

OBJECTIVE: Compared with standard medical therapy (SMT), noninvasive ventilation (NIV) does not reduce the need for reintubation in unselected patients who develop respiratory failure after extubation. The goal of this study was to assess whether early application of NIV, immediately after extubation, is effective in preventing postextubation respiratory failure in an at-risk population. DESIGN: Multiple-center, randomized controlled study. SETTING: Multiple hospitals. PATIENTS: Ninety-seven consecutive patients with similar baseline characteristics, requiring >48 hrs of mechanical ventilation and considered at risk of developing postextubation respiratory failure (i.e., patients who had hypercapnia, congestive heart failure, ineffective cough and excessive tracheobronchial secretions, more than one failure of a weaning trial, more than one comorbid condition, and upper airway obstruction). INTERVENTIONS: After a successful weaning trial, the patients were randomized to receive NIV for > or = 8 hrs a day in the first 48 hrs or SMT. Primary outcome was the need for reintubation according to standardized criteria. Secondary outcomes were intensive care unit and hospital mortality, as well as time spent in the intensive care unit and in hospital. MEASUREMENTS AND MAIN RESULTS: Compared with the SMT group, the NIV group had a lower rate of reintubation (four of 48 vs. 12 of 49; p = .027). The need for reintubation was associated with a higher risk of mortality (p < .01). The use of NIV resulted in a reduction of risk of intensive care unit mortality (-10%, p < .01), mediated by the reduction for the need of reintubation. CONCLUSIONS: NIV was more effective than SMT in preventing postextubation respiratory failure in a population considered at risk of developing this complication.

Female↗
PubMed2005

Physiologic evaluation of different levels of assistance during noninvasive ventilation delivered through a helmet.

OBJECTIVE: To evaluate the effects of various levels of pressure support (PS) during noninvasive ventilation delivered through a helmet on breathing pattern, inspiratory effort, CO2 rebreathing, and comfort. DESIGN: Physiologic study. SETTING: University-affiliated hospital. PATIENTS AND PARTICIPANTS: Eight healthy volunteers. INTERVENTIONS: Volunteers received ventilation through a helmet with four different PS/positive end-expiratory pressure combinations (5/5 cm H2O, 10/5 cm H2O, 15/5 cm H2O, and 10/10 cm H2O) applied in random order. MEASUREMENTS AND RESULTS: The ventilatory respiratory rate, esophageal respiratory rate (RRpes), airway pressure, esophageal pressure tracings, esophageal swing, and pressure-time product (PTP) [PTP per breath, PTP per minute, and PTP per liter] were evaluated. We also measured the partial pressure of inspired CO2 (Pi(CO2)) at the airway opening, mean partial pressure of expired CO2 (Pe(CO2)), CO2 production (V(CO2)), minute ventilation (V(E)) delivered to the helmet (V(E)h), and the true inspired V(E). By subtracting V(E) from V(E)h, we obtained the Ve washing the helmet (V(E)wh). A visual analog scale (from 0 to 10) was used to evaluate comfort. Compared to spontaneous breathing, different levels of PS progressively increased tidal volume (V(T)) and decreased RRpes, reducing inspiratory effort. The increased levels of assistance did not produce significant changes in Pi(CO2), end-tidal CO2, and V(CO2). Pe(CO2) had a slight decrease when increasing the level of PS from 5 to 10 cm H2O (p < 0.05). Despite the presence of constant values of Ve, the increase of PS produced an increase in V(E)wh, without significant differences comparing 10 cm H2O and 15 cm H2O of PS. The subjects had a slight but not significant increase in discomfort by augmenting the level of assistance. At the highest level of PS (15 cm H2O), the discomfort was significantly higher (p < 0.001) than at the other levels of assistance. CONCLUSION: In volunteers, the helmet is efficient in ventilation, allowing a Vt increase and RRpes reduction. A significant discomfort was present only at the highest level of assistance; however, it did not affect patient/ventilator interaction.

Adult↗
PubMed2004

Noninvasive vs invasive ventilation in COPD patients with severe acute respiratory failure deemed to require ventilatory assistance.

OBJECTIVE: To determine whether non-invasive ventilation (NIV) may be an effective and safe alternative to invasive mechanical ventilation in chronic obstructive pulmonary disease (COPD) patients with acute respiratory failure (ARF) meeting criteria for mechanical ventilation. DESIGN AND SETTING: Matched case-control study conducted in ICU. PATIENTS AND INTERVENTION: NIV was prospectively applied to 64 COPD patients with advanced ARF. Their outcomes were compared with those of a control group of 64 COPD patients matched on age, FEV(1), Simplified Acute Physiology Score II, and pH at ICU admission, previously treated in the same ICU with conventional invasive mechanical ventilation. METHODS AND RESULTS: NIV failed in 40 patients who required intubation. Mortality rate, duration of mechanical ventilation, and lengths of ICU and post-ICU stay were not different between the two groups. The NIV group had fewer complications ( P = 0.01) and showed a trend toward a lower proportion of patients remaining on mechanical ventilation after 30 days ( P = 0.056). Compared to the control group, the outcomes of the patients who failed NIV were no different. Compared to the patients who received intubation, those who succeeded NIV had reduced mortality rate and lengths of ICU and post-ICU stay. CONCLUSIONS: In COPD patients with advanced hypercapnic acute respiratory failure, NIV had a high rate of failure, but, nevertheless, provided some advantages, compared to conventional invasive ventilation. Subgroup analysis suggested that the delay in intubation was not deleterious in the patients who failed NIV, whereas a better outcome was confirmed for the patients who avoided intubation.

Acute Disease↗
PubMed2004

Noninvasive positive pressure ventilation using a helmet in patients with acute exacerbation of chronic obstructive pulmonary disease: a feasibility study.

BACKGROUND: Noninvasive positive pressure ventilation (NPPV) with a facemask (FM) is effective in patients with acute exacerbation of their chronic obstructive pulmonary disease. Whether it is feasible to treat these patients with NPPV delivered by a helmet is not known. METHODS: Over a 4-month period, the authors studied 33 chronic obstructive pulmonary disease patients with acute exacerbation who were admitted to four intensive care units and treated with helmet NPPV. The patients were compared with 33 historical controls treated with FM NPPV, matched for simplified acute physiologic score (SAPS II), age, PaCO2, pH, and PaO2:fractional inspired oxygen tension. The primary endpoints were the feasibility of the technique, improvement of gas exchange, and need for intubation. RESULTS: The baseline characteristics of the two groups were similar. Ten patients in the helmet group and 14 in the FM group (P = 0.22) were intubated. In the helmet group, no patients were unable to tolerate NPPV, whereas five patients required intubation in the FM group (P = 0.047). After 1 h of treatment, both groups had a significant reduction of PaCO2 with improvement of pH; PaCO2 decreased less in the helmet group (P = 0.01). On discontinuing support, PaCO2 was higher (P = 0.002) and pH lower (P = 0.02) in the helmet group than in the control group. One patient in the helmet group, and 12 in the FM group, developed complications related to NPPV (P < 0.001). Length of intensive care unit stay, intensive care unit, and hospital mortality were similar in both groups. CONCLUSIONS: Helmet NPPV is feasible and can be used to treat chronic obstructive pulmonary disease patients with acute exacerbation, but it does not improve carbon dioxide elimination as efficiently as does FM NPPV.

Acidosis, Respiratory↗
PubMed2003

Weaning from tracheotomy in long-term mechanically ventilated patients: feasibility of a decisional flowchart and clinical outcome.

OBJECTIVE: To assess the feasibility of following a decisional flowchart to decide whether to remove tracheotomy in long-term mechanically ventilated patients. DESIGN AND SETTING: Prospective study in a respiratory intensive care unit, with beds dedicated to weaning from prolonged mechanical ventilation. PATIENTS AND PARTICIPANTS: 108 tracheotomized patients with respiratory failure of different causes (chronic obstructive pulmonary disease, postsurgical complications, recovery from hypoxemic respiratory failure, neuromuscular disorders), 36 of whom died or could not be weaned from mechanical ventilation. INTERVENTIONS: We applied a decisional flowchart based on some simple clinical and physiological parameters aimed at assessing the patient's ability to remove secretions, swallowing function, absence of psychiatric diseases, possibility of reaching spontaneous breathing, and amount of respiratory space. MEASUREMENTS AND RESULTS: Following our flowchart 56 of the remaining patients were successfully weaned from the tracheotomy cannula, with a reintubation rate at 3 months of 3%. The main reasons for not proceeding to decannulation were inability to remove secretions and severe glottic stenosis. No statistical differences were found between patients who received a surgical or percutaneous tracheotomy. CONCLUSIONS: Using a simple decisional flowchart we were able to remove tracheotomy cannula in almost 80% of the patients with spontaneous breathing autonomy without major clinical complications. Further larger prospective studies are needed to confirm this clinical approach in larger and different populations.

APACHE↗
PubMed2003

New modes of mechanical ventilation: proportional assist ventilation, neurally adjusted ventilatory assist, and fractal ventilation.

Increased knowledge of the mechanisms that determine respiratory failure has led to the development of new technologies aimed at improving ventilatory treatment. Proportional assist ventilation and neurally adjusted ventilatory assist have been designed with the goal of improving patient-ventilator interaction by matching the ventilator support with the neural output of the respiratory centers. With proportional assist ventilation, the support is continuously readjusted in proportion to the predicted inspiratory effort. Neurally adjusted ventilatory assist is an experimental mode in which the assistance is delivered in proportion to the electrical activity of the diaphragm, assessed by means of an esophageal electrode. Biologically variable (or fractal) ventilation is a new, volume-targeted, controlled ventilation mode aimed at improving oxygenation; it incorporates the breath-to-breath variability that characterizes a natural breathing pattern.

Algorithms↗
PubMed2002

Physiological effects of translaryngeal open ventilation in patients with restrictive respiratory disorders.

OBJECTIVE: To compare the efficacy of pressure-controlled ventilation (PCV) delivered through a conventional endotracheal tube with the same ventilatory mode using a small-size tube with the cuff left deflated (translaryngeal open ventilation: TLOV). SETTING: A medical-surgical intensive care unit (ICU). DESIGN: Prospective physiological study. PATIENTS: Thirteen consecutive patients with restrictive neuromuscular and thoracic respiratory disorders ventilated in pressure-controlled mode. INTERVENTIONS: The standard tube was removed and a microlaryngeal tube (i.d. 4 mm, o.d. 6 mm, length 380 mm) was inserted with the cuff left deflated. PCV was increased to match the tracheal pressure measured during conventional ventilation. Arterial blood gases were measured before, 1 h and 20 h after initiating TLOV. A patient comfort score was measured by a visual analogue scale during conventional ventilation and 20 h after initiating TLOV (0= very bad, 1= bad, 2= quite bad, 3= sufficient, 4= good, and 5= very good). RESULTS: Inspiratory pressure was significantly increased from 16+/-5 cmH(2)O to 68+/-13 cmH(2)O after 1 h and to 65+/-12 cmH(2)O after 20 h to match the tracheal pressure measured during conventional ventilation (CV) (p<0.005). No statistically significant differences were found in arterial blood gases and patient's respiratory rate before and after 1 and 20 h of TLOV. The comfort score was 1.3+/-0.4 and 3.6+/-0.4 during CV and TLOV, respectively, on a scale from 0 to 5 (p<0.002). CONCLUSION: This study indicates that, in selected patients, TLOV was as efficient as conventional PCV.

Adolescent↗
PubMed2002

Evaluation of patient skin breakdown and comfort with a new face mask for non-invasive ventilation: a multi-center study.

OBJECTIVE: To evaluate patient comfort, skin breakdown and eye irritation when comparing a prototype face mask (PM) and conventional face masks (CMs) during non-invasive ventilation. SETTING AND DESIGN: Eight centers (intensive or intermediate care units). Multicenter randomized study. POPULATIONS: Patients with acute respiratory failure of different etiologies. INTERVENTIONS: Patients were randomized to CMs or PM when ventilation was expected to last at least 12 consecutive hours a day for two consecutive days. Patient comfort, skin breakdown and eye irritation, assessed by means of standardized scoring systems, were measured after 24 and 48 h and before discontinuing ventilation. RESULTS: Hundred ninety-four patients were randomized. Forty-seven patients were finally enrolled: PM (24) and CMs (23). Ventilator settings were similar in the two groups at the beginning of the treatment and after 24 and 48 h. Skin breakdown was significantly higher in the CMs group over the study period ( p<0.001). Patient comfort was higher in the PM group after 24 and 48 h ( p=0.008 and p<0.001, respectively). Eye irritation was absent in both groups after 24 h and did not differ significantly after 48 h (p=0.539). Before ventilation was discontinued skin breakdown and patient comfort were significantly higher in the CMs group, when compared to the PM group ( p<0.001 and p=0.003, respectively). Eye irritation was slightly higher in the PM versus CMs group ( p=0.21). The time on ventilation was not significantly different between the two groups ( p=0.830). CONCLUSION: The PM significantly reduced skin breakdown while improving patient comfort, compared to the CMs.

APACHE↗