Brazilian recommendations of mechanical ventilation 2013. Part I

Nursing care protocol for critical users with tracheostomy under mechanical ventilation

OBJECTIVES

to develop and assess a nursing care protocol for critically ill users with tracheostomy under mechanical ventilation.

METHODS

a methodological study, developed through two phases, guided by the 5W2H management tool: I) target audience characterization and II) technology development.

RESULTS

thirty-four nursing professionals participated in this study, who presented educational demands in relation to care for critical users with tracheostomy, with an emphasis on standardizing care through a protocol and carrying out continuing education.

FINAL CONSIDERATIONS

the creation and validity of new technologies aimed at this purpose enhanced the participation of nursing professionals and their empowerment in the health institution's microsectoral actions and in macrosectoral actions, highlighting the need for public policies that guarantee the conduct of a line of care for users with tracheostomy.

Ventilator hyperinflation associated with flow bias optimization in the bronchial hygiene of mechanically ventilated patients

BACKGROUND

Ventilation configurations are of great clinical importance for adequate outcomes in mechanically ventilated patients, and they may even be used as specific physical therapy techniques.

OBJECTIVES

To compare the effectiveness of lung hyperinflation through mechanical ventilation (HMV) with HMV plus flow bias optimization regarding respiratory mechanics, hemodynamics, and volume of secretion.

METHODS

Patients mechanically ventilated > 24 h were included in this randomized crossover clinical trial. The following techniques were applied: HMV alone (control group) and HMV plus flow bias optimization (intervention group).

RESULTS

The 20 included patients underwent both techniques, totaling 40 collections. A total of 52 % were women, the mean age was 60.8 (SD, 15.7) years, and the mean mechanical ventilation time was 4.3 (SD, 3.0) days. The main cause of mechanical ventilation was sepsis (44 %). Expiratory flow bias in optimized HMV was higher. than conventional HMV (p < 0.001). The volume of tracheal secretions collected was higher during optimized than conventional HMV. (p = 0.012). Significant differences in peak flow occurred at the beginning of the technique and a there was a significant decrease in respiratory system resistance immediately and 30 min after applying the technique in the intervention group.

CONCLUSIONS

The volume of tracheal secretions collected was higher during optimized HMV, and, HMV with flow bias optimization resulted in lower respiratory system resistance and flow peaks and produced expiratory flow bias.

Epidemiological profile and risk factors associated with death in patients receiving invasive mechanical ventilation in an adult intensive care unit from Brazil: a retrospective study

Introduction

Understanding the epidemiological profile and risk factors associated with invasive mechanical ventilation (IMV) is essential to manage the patients better and to improve health services. Therefore, our objective was to describe the epidemiological profile of adult patients in intensive care that required IMV in-hospital treatment. Also, to evaluate the risks associated with death and the influence of positive end-expiratory pressure (PEEP) and arterial oxygen pressure (PaO2) at admission in the clinical outcome.

Methods

We conducted an epidemiological study analyzing medical records of inpatients who received IMV from January 2016 to December 2019 prior to the Coronavirus Disease (COVID)-19 pandemic in Brazil. We considered the following characteristics in the statistical analysis: demographic data, diagnostic hypothesis, hospitalization data, and PEEP and PaO2 during IMV. We associated the patients' features with the risk of death using a multivariate binary logistic regression analysis. We adopted an alpha error of 0.05.

Results

We analyzed 1,443 medical records; out of those, 570 (39.5%) recorded the patients' deaths. The binary logistic regression was significant in predicting the patients' risk of death [X2(9) = 288.335; p < 0.001]. Among predictors, the most significant in relation to death risk were: age [elderly ≥65 years old; OR = 2.226 (95%CI = 1.728-2.867)]; male sex (OR = 0.754; 95%CI = 0.593-0.959); sepsis diagnosis (OR = 1.961; 95%CI = 1.481-2.595); need for elective surgery (OR = 0.469; 95%CI = 0.362-0.608); the presence of cerebrovascular accident (OR = 2.304; 95%CI = 1.502-3.534); time of hospital care (OR = 0.946; 95%CI = 0.935-0.956); hypoxemia at admission (OR = 1.635; 95%CI = 1.024-2.611), and PEEP >8 cmH2O at admission (OR = 2.153; 95%CI = 1.426-3.250).

Conclusion

The death rate of the studied intensive care unit was equivalent to that of other similar units. Regarding risk predictors, several demographic and clinical characteristics were associated with enhanced mortality in intensive care unit patients under mechanical ventilation, such as diabetes mellitus, systemic arterial hypertension, and older age. The PEEP >8 cmH2O at admission was also associated with increased mortality since this value is a marker of initially severe hypoxia.

Predicting tracheostomy in multiple injured patients with severe thoracic injury (AIS ≥ 3) with the new T3P-Score: a multivariable regression prediction analysis

Multiple trauma patients with severe chest trauma are at increased risk for tracheostomy. While the risk factors associated with the need for tracheostomy are well established in the general critical care population, they have not yet been validated in a cohort of patients suffering severe thoracic trauma. This retrospective cohort study analysed data on patients aged 18 years or older who were admitted to one of the six participating academic level I trauma centres with multiple injuries, including severe thoracic trauma (AIS_Thorax ≥ 3) between 2010 and 2014. A multivariable binary regression was used to identify predictor variables for tracheostomy and to develop the Tracheostomy in Thoracic Trauma Prediction Score (T₃P-Score). The study included 1019 adult thoracic trauma patients, of whom 165 underwent tracheostomy during their intensive care unit (ICU) stay. Prehospital endotracheal intubation (adjusted OR [AOR]: 2.494, 95% CI [1.412; 4.405]), diagnosis of pneumonia during the ICU stay (AOR: 4.374, 95% CI [2.503; 7.642]), duration of mechanical ventilation (AOR: 1.008/hours of intubation, 95% CI [1.006; 1.009]), and an AIS_Head ≥ 3 (AOR 1.840, 95% CI [1.039; 3.261]) were independent risk factors for tracheostomy. Patients with sepsis had a lower risk of tracheostomy than patients without sepsis (AOR 0.486, 95% CI [0.253; 0.935]). The T₃P-Score had high predictive validity for tracheostomy (ROC_AUC = 0.938, 95% CI [0.920, 0.956]; Nagelkerke's R² was 0.601). The T₃P-Score's specificity was 0.68, and the sensitivity was 0.96. The severity of thoracic trauma did not predict the need for tracheostomy. Follow-up studies should validate the T₃P-Score in external data sets and study the reasons for the reluctant use of tracheostomy in patients with severe thoracic trauma and subsequent sepsis.Trial registration: The study was applied for and registered a priori with the respective ethics committees.

Effects in vitro and in vivo of hesperidin administration in an experimental model of acute lung inflammation

Mechanical ventilation (MV) is a tool used in critical patient care. However, it can trigger inflammatory and oxidative processes capable of causing or aggravating lung injuries, which is known as ventilator-induced lung injury (VILI). Hesperidin is a flavonoid with antioxidant and anti-inflammatory properties in various diseases. The role of hesperidin in the process triggered by MV is poorly studied. Thus, we hypothesize hesperidin could protect the lung of mice submitted to mechanical ventilation. For that, we evaluated cell viability and reactive oxygen species (ROS) formation in macrophages using different hesperidin concentrations. We observed hesperidin did not reduce cell viability, however; it attenuated the production of intracellular ROS in cells stimulated with lipopolysaccharide (LPS). We further evaluated the effects of hesperidin in vivo in animals submitted to MV. In the bronchoalveolar lavage fluid, there were higher levels of macrophage, lymphocyte and neutrophil counts in animals submitted to MV, indicating an inflammatory process. In the lung tissue, MV induced oxidative damage and increased myeloperoxidase activity, though the antioxidant enzyme activity decreased. MV also induced the production of the inflammatory mediators CCL-2, TNF-α and IL-12. Pretreatment with hesperidin resulted in less recruitment of inflammatory cells to the airways and less oxidative damage. Also, it reduced the formation of CCL-2 and IL-12. Our results show pretreatment with hesperidin can protect the lungs of mice submitted to mechanical ventilation by modulating the inflammatory response and redox imbalance and may act to prevent MV injury.

Possible solutions for oxygenation support in critically ill patients with COVID-19

Purpose

Due to the large number of patients with respiratory deficiency during the COVID-19 pandemic, several governments and their respective health care services have been studying ways to complement the care provided by offering immediate solutions. In view of this, the aim of this study was to carry out a systematic review of the advantages and disadvantages of possible solutions in oxygenation support.

Methods

This systematic review used the PRISMA-P methodology and sought to list alternatives in oxygenation support that are being applied and studied worldwide. A bibliographic search was conducted in the MEDLINE and Cochrane Central databases, using the keywords SARS-CoV-2, COVID19, or coronavirus; combined with extracorporeal membrane oxygenation (ECMO), mechanical ventilation, mechanical ventilation support, low-cost, anesthesia, anesthesia machine, and ventilation therapy. The records were also found in the gray literature.

Results

The search found 85 publications of which 41 articles were considered after excluding duplicate articles, reading the title and summary, and reading the articles in full. The oxygenation supports identified in these publications were the following: ECMO, shared mechanical ventilator, fast or low-cost production equipment, high-flow nasal cannula (HFNC), non-invasive ventilation, and use of anesthesia equipment as a mechanical ventilator.

Conclusion

This study demonstrated the importance of a trained clinical team in the application of technologies. The alternatives found for support oxygenation require a more robust clinical evaluation to demonstrate their efficacy and safety for the COVID-19 patient.

Incentive spirometer: Aspects of the clinical practice of physical therapists from Minas Gerais working with patients with respiratory dysfunction

BACKGROUND

Incentive spirometers (ISs) are clinical devices used in respiratory physical therapy to increase alveolar ventilation and functional residual capacity.

OBJECTIVES

To investigate factors that influence physical therapists from Minas Gerais in selecting a type of IS and the scientific background behind the use of ISs by physical therapists who work with patients with respiratory dysfunctions.

METHODS

Physical therapists from 13 hospital and non-hospital institutions (public/private) completed a self-administered questionnaire based on the current evidence on ISs.

RESULTS

Indications and contraindications of ISs are not fully understood by most of the 168 physical therapists who completed the questionnaire. Volume-oriented IS was preferred over flow-oriented IS. However, only half of the physical therapists have a scientific background to justify the choice of one IS type rather than the other.

CONCLUSIONS

Most physical therapists from Minas Gerais do not fully understand the indications and contraindications for ISs. Despite physical therapists stating their preference for volume-oriented IS, this choice is not necessarily based on current scientific evidence. The development of strategies to bring physical therapists closer to evidence-based practice is necessary to ensure best patient care.

Implementation of Tele-ICU during the COVID-19 pandemic

OBJECTIVE

To describe the implementation of a Tele-ICU program during the COVID-19 pandemic, as well as to describe and analyze the results of the first four months of operation of the program.

METHODS

This was a descriptive observational study of the implementation of a Tele-ICU program, followed by a retrospective analysis of clinical data of patients with COVID-19 admitted to ICUs between April and July of 2020.

RESULTS

The Tele-ICU program was implemented over a four-week period and proved to be feasible during the pandemic. Participants were trained remotely, and the program had an evidence-based design, the objective being to standardize care for patients with COVID-19. More than 100,000 views were recorded on the free online platforms and the mobile application. During the study period, the cases of 326 patients with COVID-19 were evaluated through the program. The median age was 60 years (IQR, 49-68 years). There was a predominance of males (56%). There was also a high prevalence of hypertension (49.1%) and diabetes mellitus (38.4%). At ICU admission, 83.7% of patients were on invasive mechanical ventilation, with a median PaO2/FiO2 ratio < 150. It was possible to use lung-protective ventilation in 75% of the patients. Overall, in-hospital mortality was 68%, and ICU mortality was 65%.

CONCLUSIONS

Our Tele-ICU program provided multidisciplinary training to health care professionals and clinical follow-up for hundreds of critically ill patients. This public health care network initiative was unprecedented and proved to be feasible during the COVID-19 pandemic, encouraging the creation of similar projects that combine evidence-based practices, training, and Tele-ICU.

Failure of Noninvasive Ventilation in Acute Respiratory Failure is Associated with Higher Mortality in Patients with Solid Tumors: A Retrospective Cohort Study

BACKGROUND

Noninvasive Ventilation (NIV) is a well-established treatment for Acute Respiratory Failure (ARF) in hematological cancer. However, the NIV impact on mortality in patients with solid tumors is unclear.

OBJECTIVE

To define the factors associated with NIV failure and mortality and to describe the mortality risk of patients with solid tumors requiring NIV for ARF treatment in the intensive care unit (ICU).

METHODS

A retrospective cohort study of patients with solid tumors admitted into an ICU between Jan 2016 and Dec 2017, for cancer treatment, with ARF diagnosis that had used the NIV as first-line treatment. Our primary outcome was ICU and in-hospital mortality. The secondary outcome was NIV failure. A Cox proportional hazards regression was used to identify variables associated with mortality and NIV failure. Kaplan-Meier analyses were performed to demonstrate cumulative survival.

RESULTS

A total of 226 patients with solid tumors were included. The ICU and hospital mortality rates were 57.5% and 69.5%, respectively. NIV failed in 52.2% of the patients. The use of vasopressors (HR 2.48 [95% CI: 1.43-4.30] p = 0.001), baseline lactate (HR 1.20 [95% CI: 1.07-1.35] p = 0.003), baseline PaO₂/FiO₂ ratio (HR1.33 [1.11-1.55] p = 0.002), and NIV success (HR0.17 [95% CI: 0.10-0.27] p = 0.005) was independently associated with hospital mortality. The use of vasopressors (HR 2.58 [95% CI: 1.41-4.73] p = 0.02), NIV duration (HR 0.93 [95% CI: 0.89-0.97] p = 0.003), and baseline lactate (HR 1.13 [95% CI: 1.06-1.20] p = 0.001) was associated with NIV failure.

CONCLUSIONS

NIV failure was independently associated with an increase in both ICU and hospital mortality rates. In patients with NIV therapy indication, the duration of this intervention was associated with NIV failure.

Driving pressure and mortality in trauma without acute respiratory distress syndrome: a prospective observational study

Objective

To identify the possible association between driving pressure and mechanical power values and oxygenation index on the first day of mechanical ventilation with the mortality of trauma patients without a diagnosis of acute respiratory distress syndrome.

Methods

Patients under pressure-controlled or volume-controlled ventilation were included, with data collection 24 hours after orotracheal intubation. Patient follow-up was performed for 30 days to obtain the clinical outcome. The patients were admitted to two intensive care units of the Hospital de Pronto Socorro de Porto Alegre from June to September 2019.

Results

A total of 24 patients were evaluated. Driving pressure, mechanical power and oxygenation index were similar among patients who survived and those who died, with no statistically significant difference between groups.

Conclusion

Driving pressure, mechanical power and oxygenation index values obtained on the first day of mechanical ventilation were not associated with mortality of trauma patients without acute respiratory distress syndrome.

Protective mechanical ventilation in suspected influenza infection

INTRODUCTION:

Patients with acute respiratory failure due to influenza require ventilatory support. However, mechanical ventilation itself can exacerbate lung damage and increase mortality.

METHODS:

The aim of this study was to describe a feasible and protective ventilation protocol, with limitation of the tidal volume to ≤6 mL/kg of the predicted weight and a driving pressure ≤15 cmH₂O after application of the alveolar recruitment maneuver and PEEP titration.

RESULTS:

Initial improvement in oxygenation and respiratory mechanics were observed in the four cases submitted to the proposed protocol.

CONCLUSIONS:

Our results indicate that the mechanical ventilation strategy applied could be optimized.

Challenges for the development of alternative low-cost ventilators during COVID-19 pandemic in Brazil

The COVID-19 pandemic has brought concerns to managers, healthcare professionals, and the general population related to the potential mechanical ventilators’ shortage for severely ill patients. In Brazil, there are several initiatives aimed at producing alternative ventilators to cover this gap. To assist the teams that work in these initiatives, we provide a discussion of some basic concepts on physiology and respiratory mechanics, commonly used mechanical ventilation terms, the differences between triggering and cycling, the basic ventilation modes and other relevant aspects, such as mechanisms of ventilator-induced lung injury, respiratory drive, airway heating and humidification, cross-contamination risks, and aerosol dissemination. After the prototype development phase, preclinical bench-tests and animal model trials are needed to determine the safety and performance of the ventilator, following the minimum technical requirements. Next, it is mandatory going through the regulatory procedures as required by the Brazilian Health Regulatory Agency (Agência Nacional de Vigilância Sanitária - ANVISA). The manufacturing company should be appropriately registered by ANVISA, which also must be notified about the conduction of clinical trials, following the research protocol approval by the Research Ethics Committee. The registration requisition of the ventilator with ANVISA should include a dossier containing the information described in this paper, which is not intended to cover all related matters but to provide guidance on the required procedures.

Factors associated with non-invasive mechanical ventilation failure in patients with hematological neoplasia and their association with outcomes

BACKGROUND

The usefulness of non-invasive mechanical ventilation (NIMV) in oncohematological patients is still a matter of debate.

AIM

To analyze the rate of noninvasive ventilation failure and the main characteristics associated with this endpoint in oncohematological patients with acute respiratory failure (ARF).

METHODS

A ventilatory support protocol was developed and implemented before the onset of the study. According to the PaO2/FiO2 (P/F) ratio and clinical judgment, patients received supplementary oxygen therapy, NIMV, or invasive mechanical ventilation (IMV).

RESULTS

Eighty-two patients were included, average age between 52.1 ± 16 years old; 44 (53.6%) were male. The tested protocol was followed in 95.1% of cases. Six patients (7.3%) received IMV, 59 (89.7%) received NIMV, and 17 (20.7%) received oxygen therapy. ICU mortality rates were significantly higher in the IMV (83.3%) than in the NIMV (49.2%) and oxygen therapy (5.9%) groups (P < 0.001). Among the 59 patients who initially received NIMV, 30 (50.8%) had to eventually be intubated. Higher SOFA score at baseline (1.35 [95% CI = 1.12-2.10], P = 0.007), higher respiratory rate (RR) (1.10 [95% CI = 1.00-1.22], P = 0.048), and sepsis on admission (16.9 [95% CI = 1.93-149.26], P = 0.011) were independently associated with the need of orotracheal intubation among patients initially treated with NIMV. Moreover, NIMV failure was independently associated with ICU (P < 0.001) and hospital mortality (P = 0.049), and mortality between 6 months and 1 year (P < 0.001).

CONCLUSION

The implementation of a NIMV protocol is feasible in patients with hematological neoplasia admitted to the ICU, even though its benefits still remain to be demonstrated. NIMV failure was associated with higher SOFA and RR and more frequent sepsis, and it was also related to poor prognosis.

Neurally adjusted ventilatory assist vs. pressure support to deliver protective mechanical ventilation in patients with acute respiratory distress syndrome: a randomized crossover trial

Background

Protective mechanical ventilation is recommended for patients with acute respiratory distress syndrome (ARDS), but it usually requires controlled ventilation and sedation. Using neurally adjusted ventilatory assist (NAVA) or pressure support ventilation (PSV) could have additional benefits, including the use of lower sedative doses, improved patient–ventilator interaction and shortened duration of mechanical ventilation. We designed a pilot study to assess the feasibility of keeping tidal volume (V_T) at protective levels with NAVA and PSV in patients with ARDS.

Methods

We conducted a prospective randomized crossover trial in five ICUs from a university hospital in Brazil and included patients with ARDS transitioning from controlled ventilation to partial ventilatory support. NAVA and PSV were applied in random order, for 15 min each, followed by 3 h in NAVA. Flow, peak airway pressure (Paw) and electrical activity of the diaphragm (EAdi) were captured from the ventilator, and a software (Matlab, Mathworks, USA), automatically detected inspiratory efforts and calculated respiratory rate (RR) and V_T. Asynchrony events detection was based on waveform analysis.

Results

We randomized 20 patients, but the protocol was interrupted for five (25%) patients for whom we were unable to maintain V_T below 6.5 mL/kg in PSV due to strong inspiratory efforts and for one patient for whom we could not detect EAdi signal. For the 14 patients who completed the protocol, V_T was 5.8 ± 1.1 mL/kg for NAVA and 5.6 ± 1.0 mL/kg for PSV (p = 0.455) and there were no differences in RR (24 ± 7 for NAVA and 23 ± 7 for PSV, p = 0.661). Paw was greater in NAVA (21 ± 3 cmH₂O) than in PSV (19 ± 3 cmH₂O, p = 0.001). Most patients were under continuous sedation during the study. NAVA reduced triggering delay compared to PSV (p = 0.020) and the median asynchrony Index was 0.7% (0–2.7) in PSV and 0% (0–2.2) in NAVA (p = 0.6835).

Conclusions

It was feasible to keep V_T in protective levels with NAVA and PSV for 75% of the patients. NAVA resulted in similar V_T, RR and Paw compared to PSV. Our findings suggest that partial ventilatory assistance with NAVA and PSV is feasible as a protective ventilation strategy in selected ARDS patients under continuous sedation.

Trial registration ClinicalTrials.gov (NCT01519258). Registered 26 January 2012, https://clinicaltrials.gov/ct2/show/NCT01519258

Boas práticas de enfermagem a pacientes em ventilação mecânica invasiva na emergência hospitalara

RESUMO Objetivo Identificar os cuidados concebidos como boas práticas de enfermagem a pacientes em ventilação mecânica invasiva no contexto de emergência hospitalar. Método Estudo descritivo, qualitativo, realizado de junho a setembro de 2017. Participaram 16 enfermeiros da emergência geral de um hospital da região Sul do Brasil. Os cuidados, extraídos da literatura e classificados quanto ao nível de evidência, foram agrupados em categorias por similaridade e selecionados nos Grupos de Discussão. Resultados Os enfermeiros consideraram como boas práticas aos pacientes em ventilação mecânica invasiva um total de 13 cuidados, os quais estão relacionados ao tubo endotraqueal, ao ventilador e circuito, à prevenção de broncoaspiração, ao controle de infecção e à sedação, analgesia/sono, vigília/dor. Os cuidados foram extraídos de estudos com níveis de evidência IIb, IV e VI. Conclusão e implicações para a prática As boas práticas de enfermagem em ventilação mecânica invasiva, concebidas pelos enfermeiros da emergência, respaldam cientificamente a assistência ao paciente em suporte ventilatório invasivo, podendo ser aplicadas em contextos similares.

Extracorporeal membrane oxygenation: a literature review

Extracorporeal membrane oxygenation is a modality of extracorporeal life support that allows for temporary support in pulmonary and/or cardiac failure refractory to conventional therapy. Since the first descriptions of extracorporeal membrane oxygenation, significant improvements have occurred in the device and the management of patients and, consequently, in the outcomes of critically ill patients during extracorporeal membrane oxygenation. Many important studies about the use of extracorporeal membrane oxygenation in patients with acute respiratory distress syndrome refractory to conventional clinical support, under in-hospital cardiac arrest and with cardiogenic refractory shock have been published in recent years. The objective of this literature review is to present the theoretical and practical aspects of extracorporeal membrane oxygenation support for respiratory and/or cardiac functions in critically ill patients.

Sizing the lung in dogs: the inspiratory capacity defines the tidal volume

Objective

To evaluate a novel physiological approach for setting the tidal volume in mechanical ventilation according to inspiratory capacity, and to determine if it results in an appropriate mechanical and gas exchange measurements in healthy and critically ill dogs.

Methods

Twenty healthy animals were included in the study to assess the tidal volume expressed as a percentage of inspiratory capacity. For inspiratory capacity measurement, the mechanical ventilator was set as follows: pressure control mode with 35cmH₂O of inspired pressure and zero end-expiratory pressure for 5 seconds. Subsequently, the animals were randomized into four groups and ventilated with a tidal volume corresponding to the different percentages of inspiratory capacity. Subsequently, ten critically ill dogs were studied.

Results

Healthy dogs ventilated with a tidal volume of 17% of the inspiratory capacity showed normal respiratory mechanics and presented expected PaCO₂ values more frequently than the other groups. The respiratory system and transpulmonary driving pressure were significantly higher among the critically ill dogs but below 15 cmH₂O in all cases.

Conclusions

The tidal volume based on the inspiratory capacity of each animal has proven to be a useful and simple tool when setting ventilator parameters. A similar approach should also be evaluated in other species, including human beings, if we consider the potential limitations of tidal volume titration based on the calculated ideal body weight.

Tracheal cuff pressure change before and after the performance of nursing care

OBJECTIVE

Verify the changes of endotracheal cuff pressure before and after oral hygiene, head-of-bed elevation at 0º, 30º, and 60º, change in body position, aspiration of the endotracheal tube, and in-bed bathing.

METHOD

The study sample was composed of 88 patients. We performed 3,696 checks from July to September 2014.

RESULTS

Pressure values were analyzed in seven nursing care in the morning. Six of them were significantly altered before and after nursing procedure. In the afternoon, five of the health care provided were altered, and in the evening, only two. Most of pressure values were below recommended.

CONCLUSION

There were differences before and after health care provided, showing changes in cuff pressure. In-bed bathing and head-of-bed elevation at 30º were the ones that most altered pressure values in the three working shifts. Therefore, it is necessary to measure cuff pressure at least twice per working shift, preferably after bathing.

Patient-ventilator asynchrony

Patient-v entilator asynchrony (PVA) is a mismatch between the patient, regarding time, flow, volume, or pressure demands of the patient respiratory system, and the ventilator, which supplies such demands, during mechanical ventilation (MV). It is a common phenomenon, with incidence rates ranging from 10% to 85%. PVA might be due to factors related to the patient, to the ventilator, or both. The most common PVA types are those related to triggering, such as ineffective effort, auto-triggering, and double triggering; those related to premature or delayed cycling; and those related to insufficient or excessive flow. Each of these types can be detected by visual inspection of volume, flow, and pressure waveforms on the mechanical ventilator display. Specific ventilatory strategies can be used in combination with clinical management, such as controlling patient pain, anxiety, fever, etc. Deep sedation should be avoided whenever possible. PVA has been associated with unwanted outcomes, such as discomfort, dyspnea, worsening of pulmonary gas exchange, increased work of breathing, diaphragmatic injury, sleep impairment, and increased use of sedation or neuromuscular blockade, as well as increases in the duration of MV, weaning time, and mortality. Proportional assist ventilation and neurally adjusted ventilatory assist are modalities of partial ventilatory support that reduce PVA and have shown promise. This article reviews the literature on the types and causes of PVA, as well as the methods used in its evaluation, its potential implications in the recovery process of critically ill patients, and strategies for its resolution.

AIRWAY POSITIVE PRESSURE VS. EXERCISES WITH INSPIRATORY LOADING FOCUSED ON PULMONARY AND RESPIRATORY MUSCULAR FUNCTIONS IN THE POSTOPERATIVE PERIOD OF BARIATRIC SURGERY

BACKGROUND

Bariatric surgery can trigger postoperative pulmonary complications due to factors inherent to the procedure, mainly due to diaphragmatic dysfunction.

AIM

To evaluate and compare the effects of two levels of positive pressure and exercises with inspiratory load on lung function, inspiratory muscle strength and respiratory muscle resistance, and the prevalence of atelectasis after gastroplasty.

METHODS

Clinical, randomized and blind trial, with subjects submitted to bariatric surgery, allocated to two groups: positive pressure group, who received positive pressure at two levels during one hour and conventional respiratory physiotherapy and inspiratory load group, who performed exercises with load linear inspiratory pressure, six sets of 15 repetitions, in addition to conventional respiratory physiotherapy, both of which were applied twice in the immediate postoperative period and three times a day on the first postoperative day. Spirometry was performed for pulmonary function analysis, nasal inspiratory pressure for inspiratory muscle strength and incremental test of respiratory muscle resistance for sustained maximal inspiratory pressure, both preoperatively and on hospital discharge on the second postoperative day.

RESULTS

There was no significant difference (p> 0.05) in the expiratory reserve volume and in the tidal volume in the pre and postoperative periods when compared intra and intergroup. There was no significant difference (p>0.05) in the nasal inspiratory pressure and the maximal inspiratory pressure maintained in the inspiratory load group in the intragroup evaluation, but with a significant difference (p<0.05) compared to the positive pressure group. The prevalence of atelectasis was 5% in both groups with no significant difference (p>0.05) between them.

CONCLUSION

Both groups, associated with conventional respiratory physiotherapy, preserved expiratory reserve volume and tidal volume and had a low atelectasis rate. The inspiratory loading group still maintained inspiratory muscle strength and resistance of respiratory muscles.

Use of noninvasive ventilation in severe acute respiratory distress syndrome due to accidental chlorine inhalation: a case report

Acute respiratory distress syndrome is characterized by diffuse inflammatory lung injury and is classified as mild, moderate, and severe. Clinically, hypoxemia, bilateral opacities in lung images, and decreased pulmonary compliance are observed. Sepsis is one of the most prevalent causes of this condition (30 - 50%). Among the direct causes of acute respiratory distress syndrome, chlorine inhalation is an uncommon cause, generating mucosal and airway irritation in most cases. We present a case of severe acute respiratory distress syndrome after accidental inhalation of chlorine in a swimming pool, with noninvasive ventilation used as a treatment with good response in this case. We classified severe acute respiratory distress syndrome based on an oxygen partial pressure/oxygen inspired fraction ratio <100, although the Berlin classification is limited in considering patients with severe hypoxemia managed exclusively with noninvasive ventilation. The failure rate of noninvasive ventilation in cases of acute respiratory distress syndrome is approximately 52% and is associated with higher mortality. The possible complications of using noninvasive positive-pressure mechanical ventilation in cases of acute respiratory distress syndrome include delays in orotracheal intubation, which is performed in cases of poor clinical condition and with high support pressure levels, and deep inspiratory efforts, generating high tidal volumes and excessive transpulmonary pressures, which contribute to ventilation-related lung injury. Despite these complications, some studies have shown a decrease in the rates of orotracheal intubation in patients with acute respiratory distress syndrome with low severity scores, hemodynamic stability, and the absence of other organ dysfunctions.

Impact of continuous positive airway pressure on the pulmonary changes promoted by immersion in water

OBJECTIVE

To determine whether different levels of CPAP improve the lung volumes and capacities of healthy subjects immersed in water.

METHODS

This was a randomized clinical trial, conducted between April and June of 2016, involving healthy female volunteers who were using oral contraceptives. Three 20-min immersion protocols were applied: control (no CPAP); CPAP5 (CPAP at 5 cmH2O); and CPAP10 (CPAP at 10 cmH2O). We evaluated HR, SpO2, FVC, FEV1, the FEV1/FVC ratio, peak expiratory flow rate (PEFR), and FEF25-75%) at three time points: pre-immersion; 10 min after immersion; and 10 min after the end of each protocol.

RESULTS

We evaluated 13 healthy volunteers. The CPAP10 protocol reversed the restrictive pattern of lung function induced by immersion in water, maintaining pulmonary volumes and capacities for a longer period than did the CPAP5 protocol.

CONCLUSIONS

When the hemodynamic change causing a persistent lung disorder, only the application of higher positive pressures is effective in maintaining long-term improvements in the pulmonary profile.

Patient-ventilator asynchrony

Patient-v entilator asynchrony (PVA) is a mismatch between the patient, regarding time, flow, volume, or pressure demands of the patient respiratory system, and the ventilator, which supplies such demands, during mechanical ventilation (MV). It is a common phenomenon, with incidence rates ranging from 10% to 85%. PVA might be due to factors related to the patient, to the ventilator, or both. The most common PVA types are those related to triggering, such as ineffective effort, auto-triggering, and double triggering; those related to premature or delayed cycling; and those related to insufficient or excessive flow. Each of these types can be detected by visual inspection of volume, flow, and pressure waveforms on the mechanical ventilator display. Specific ventilatory strategies can be used in combination with clinical management, such as controlling patient pain, anxiety, fever, etc. Deep sedation should be avoided whenever possible. PVA has been associated with unwanted outcomes, such as discomfort, dyspnea, worsening of pulmonary gas exchange, increased work of breathing, diaphragmatic injury, sleep impairment, and increased use of sedation or neuromuscular blockade, as well as increases in the duration of MV, weaning time, and mortality. Proportional assist ventilation and neurally adjusted ventilatory assist are modalities of partial ventilatory support that reduce PVA and have shown promise. This article reviews the literature on the types and causes of PVA, as well as the methods used in its evaluation, its potential implications in the recovery process of critically ill patients, and strategies for its resolution.

Analysis of ineffective breathing pattern and impaired spontaneous ventilation of adults with oxygen therapy

Objective:

to analyze the manifestation of the defining characteristics of the nursing diagnoses of ineffective breathing pattern and impaired spontaneous ventilation, of the NANDA International and the defining characteristics identified in the literature for the concept of “ventilation” in adult patients hospitalized in an intensive care unit with use of oxygen therapy.

Method:

clinical diagnostic validation study, conducted with 626 patients in intensive care using oxygen therapy, in three different modalities. Multiple correspondence analysis was used to verify the discriminative capacity of the defining characteristics and latent class analysis to determine the diagnostic accuracy of them, based on the severity level defined by the ventilatory mode used.

Results:

in the multiple correspondence analysis, it was demonstrated that the majority of the defining characteristics presented low discriminative capacity and low percentage of explained variance for the two dimensions (diagnoses). Latent class models, separately adjusted for the two diagnoses, presented a worse fit, with sharing of some defining characteristics. Models adjusted by level of severity (ventilation mode) presented better fit and structure of the component defining characteristics.

Conclusion:

clinical evidence obtained in the present study seems to demonstrate that the set of defining characteristics of the two nursing diagnoses studied fit better in a single construct.

Potential clinical application of surface electromyography as indicator of neuromuscular recovery during weaning tests after organophosphate poisoning

This study aimed to explore the usefulness of measuring respiratory muscle activity in mechanically ventilated patients suffering from acute organophosphate poisoning, with a view towards providing complementary information to determine the best time to suspend ventilatory support. Surface electromyography in respiratory muscles (diaphragm, external intercostal and sternocleidomastoid muscles) was recorded in a young man affected by self-poisoning with an unknown amount of parathion to determine the muscle activity level during several weaning attempts from mechanical ventilation. The energy distribution of each surface electromyography signal frequency, the synchronization between machine and patient and between muscles, acetylcholinesterase enzyme activity, and work of breathing and rapid shallow breathing indices were calculated in each weaning attempt. The work of breathing and rapid shallow breathing indices were not correlated with the failure/success of the weaning attempt. The diaphragm gradually increased its engagement with ventilation, achieving a maximal response that correlated with successful weaning and maximal acetylcholinesterase enzyme activity; in contrast, the activity of accessory respiratory muscles showed an opposite trend.

Effect of Different Levels of Peep on Oxygenation during Non-Invasive Ventilation in Patients Submitted to CABG Surgery: Randomized Clinical Trial

INTRODUCTION

During and after coronary artery bypass grafting, a decline in multifactor lung function is observed. Due to this fact, some patients may benefit from non-invasive ventilation after extubation targeting lung expansion and consequently improved oxygenation.

OBJECTIVE

To test the hypothesis that higher levels of positive end expiration pressure during non-invasive ventilation improves oxygenation in patients undergoing coronary artery bypass grafting.

METHODS

A randomized clinical trial was conducted at Instituto Nobre de Cardiologia in Feira de Santana. On the first day after surgery, the patients were randomized: Group PEEP 10, Group PEEP 12 and Group PEEP 15 who underwent non-invasive ventilation with positive end expiration pressure level. All patients were submitted to analysis blood pressure oxygen (PaO2), arterial oxygen saturation (SaO2) and oxygenation index (PaO2/FiO2).

RESULTS

Thirty patients were analyzed, 10 in each group, with 63.3% men with a mean age of 61.1±12.2 years. Mean pulmonary expansion pre-therapy PaO2 was generally 121.9±21.6 to 136.1±17.6 without statistical significance in the evaluation among the groups. This was also present in PaO2/FiO2 and SaO2. Statistical significance was only present in pre and post PEEP 15 when assessing the PaO2 and SaO2 (P=0.02).

CONCLUSION

Based on the findings of this study, non-invasive ventilation with PEEP 15 represented an improvement in oxygenation levels of patients undergoing coronary artery bypass grafting.

Influence of the ventilatory mode on acute adverse effects and facial thermography after noninvasive ventilation

OBJECTIVE:

To compare the incidence and intensity of acute adverse effects and the variation in the temperature of facial skin by thermography after the use of noninvasive ventilation (NIV).

METHODS:

We included 20 healthy volunteers receiving NIV via oronasal mask for 1 h. The volunteers were randomly divided into two groups according to the ventilatory mode: bilevel positive airway pressure (BiPAP) or continuous positive airway pressure (CPAP). Facial thermography was performed in order to determine the temperature of the face where it was in contact with the mask and of the nasal dorsum at various time points. After removal of the mask, the volunteers completed a questionnaire about adverse effects of NIV.

RESULTS:

The incidence and intensity of acute adverse effects were higher in the individuals receiving BiPAP than in those receiving CPAP (16.1% vs. 5.6%). Thermographic analysis showed a significant cooling of the facial skin in the two regions of interest immediately after removal of the mask. The more intense acute adverse effects occurred predominantly among the participants in whom the decrease in the mean temperature of the nasal dorsum was lower (14.4% vs. 7.2%). The thermographic visual analysis of the zones of cooling and heating on the face identified areas of hypoperfusion or reactive hyperemia.

CONCLUSIONS:

The use of BiPAP mode was associated with a higher incidence and intensity of NIV-related acute adverse effects. There was an association between acute adverse effects and less cooling of the nasal dorsum immediately after removal of the mask. Cutaneous thermography can be an additional tool to detect adverse effects that the use of NIV has on facial skin.

OBJETIVO:

Comparar a incidência e a intensidade de efeitos adversos agudos e a variação da temperatura da pele da face através da termografia após a aplicação de ventilação não invasiva (VNI).

MÉTODOS:

Foram incluídos 20 voluntários sadios, de ambos os gêneros, submetidos à VNI com máscara oronasal por 1 h e divididos aleatoriamente em dois grupos de acordo com o modo ventilatório: bilevel positive airway pressure (BiPAP) ou continuous positive airway pressure (CPAP). A termografia da face foi realizada para determinar a temperatura na região de contato da máscara e no dorso do nariz em momentos diferentes. Os voluntários preencheram um questionário de efeitos adversos após a retirada da VNI.

RESULTADOS:

A incidência e a intensidade dos efeitos adversos agudos foram maiores naqueles submetidos a BiPAP em relação aos submetidos a CPAP (16,1% vs. 5,6%). A análise termográfica evidenciou um esfriamento significativo da pele facial nas duas regiões de estudo imediatamente após a retirada da máscara. Os efeitos adversos agudos em maior intensidade ocorreram predominantemente no grupo de participantes cuja redução da temperatura média no dorso do nariz foi menor (14,4% vs. 7,2%). A análise visual termográfica de zonas de esfriamento e aquecimento na face identificou regiões de hipoperfusão ou hiperemia reativa.

CONCLUSÕES:

O uso do modo BiPAP associou-se a maior incidência e intensidade de efeitos adversos agudos associados à VNI. Houve associação entre efeitos adversos agudos e menor esfriamento da pele do dorso do nariz imediatamente após a retirada da máscara. A termografia cutânea pode ser uma ferramenta adicional na detecção de efeitos adversos na pele da face associados ao uso da VNI.

Mechanical ventilation in Coffin-Lowry syndrome: a case report

We describe a 27-year-old patient with Coffin-Lowry syndrome with severe community pneumonia, septic shock and respiratory failure. We summarize both the mechanical ventilatory assistance and the hospitalization period in the intensive care unit.

Use of noninvasive ventilation in severe acute respiratory distress syndrome due to accidental chlorine inhalation: a case report

Acute respiratory distress syndrome is characterized by diffuse inflammatory lung injury and is classified as mild, moderate, and severe. Clinically, hypoxemia, bilateral opacities in lung images, and decreased pulmonary compliance are observed. Sepsis is one of the most prevalent causes of this condition (30 - 50%). Among the direct causes of acute respiratory distress syndrome, chlorine inhalation is an uncommon cause, generating mucosal and airway irritation in most cases. We present a case of severe acute respiratory distress syndrome after accidental inhalation of chlorine in a swimming pool, with noninvasive ventilation used as a treatment with good response in this case. We classified severe acute respiratory distress syndrome based on an oxygen partial pressure/oxygen inspired fraction ratio <100, although the Berlin classification is limited in considering patients with severe hypoxemia managed exclusively with noninvasive ventilation. The failure rate of noninvasive ventilation in cases of acute respiratory distress syndrome is approximately 52% and is associated with higher mortality. The possible complications of using noninvasive positive-pressure mechanical ventilation in cases of acute respiratory distress syndrome include delays in orotracheal intubation, which is performed in cases of poor clinical condition and with high support pressure levels, and deep inspiratory efforts, generating high tidal volumes and excessive transpulmonary pressures, which contribute to ventilation-related lung injury. Despite these complications, some studies have shown a decrease in the rates of orotracheal intubation in patients with acute respiratory distress syndrome with low severity scores, hemodynamic stability, and the absence of other organ dysfunctions.

Use of thoracic electrical impedance tomography as an auxiliary tool for alveolar recruitment maneuvers in acute respiratory distress syndrome: case report and brief literature review

Thoracic electrical impedance tomography is a real-time, noninvasive monitoring tool of the regional pulmonary ventilation distribution. Its bedside use in patients with acute respiratory distress syndrome has the potential to aid in alveolar recruitment maneuvers, which are often necessary in cases of refractory hypoxemia. In this case report, we describe the monitoring results and interpretation of thoracic electrical impedance tomography used during alveolar recruitment maneuvers in a patient with acute respiratory distress syndrome, with transient application of high alveolar pressures and optimal positive end-expiratory pressure titration. Furthermore, we provide a brief literature review regarding the use of alveolar recruitment maneuvers and monitoring using thoracic electrical impedance tomography in patients with acute respiratory distress syndrome.

Acute respiratory distress syndrome

Acute respiratory distress syndrome presents as hypoxia and bilateral pulmonary infiltrates on chest imaging in the absence of heart failure sufficient to account for this clinical state. Management is largely supportive, and is focused on protective mechanical ventilation and the avoidance of fluid overload. Patients with severe hypoxaemia can be managed with early short-term use of neuromuscular blockade, prone position ventilation, or extracorporeal membrane oxygenation. The use of inhaled nitric oxide is rarely indicated and both β₂ agonists and late corticosteroids should be avoided. Mortality remains at approximately 30%.

A Critical Review of Mechanical Ventilation Virtual Simulators: Is It Time to Use Them?

BACKGROUND

Teaching mechanical ventilation at the bedside with real patients is difficult with many logistic limitations. Mechanical ventilators virtual simulators (MVVS) may have the potential to facilitate mechanical ventilation (MV) training by allowing Web-based virtual simulation.

OBJECTIVE

We aimed to identify and describe the current available MVVS, to compare the usability of their interfaces as a teaching tool and to review the literature on validation studies.

METHODS

We performed a comparative evaluation of the MVVS, based on a literature/Web review followed by usability tests according to heuristic principles evaluation of their interfaces as performed by professional experts on MV.

RESULTS

Eight MVVS were identified. They showed marked heterogeneity, mainly regarding virtual patient's anthropomorphic parameters, pulmonary gas exchange, respiratory mechanics and muscle effort configurations, ventilator terminology, basic ventilatory modes, settings alarms, monitoring parameters, and design. The Hamilton G5 and the Xlung covered a broader number of parameters, tools, and have easier Web-based access. Except for the Xlung, none of the simulators displayed monitoring of arterial blood gases and alternatives to load and save the simulation. The Xlung obtained the greater scores on heuristic principles assessments and the greater score of easiness of use, being the preferred MVVS for teaching purposes. No strong scientific evidence on the use and validation of the current MVVS was found.

CONCLUSIONS

There are only a few MVVS currently available. Among them, the Xlung showed a better usability interface. Validation tests and development of new or improvement of the current MVVS are needed.

Assistance of inhalation injury victims caused by fire in confined spaces: what we learned from the tragedy at Santa Maria

On January 2013, a disaster at Santa Maria (RS) due to a fire in a confined space caused 242 deaths, most of them by inhalation injury. On November 2013, four individuals required intensive care following smoke inhalation from a fire at the Memorial da América Latina in São Paulo (SP). The present article reports the clinical progression and management of disaster victims presenting with inhalation injury. Patients ERL and OC exhibited early respiratory failure, bronchial aspiration of carbonaceous material, and carbon monoxide poisoning. Ventilation support was performed with 100% oxygen, the aspirated material was removed by bronchoscopy, and cyanide poisoning was empirically treated with sodium nitrite and sodium thiosulfate. Patient RP initially exhibited cough and retrosternal burning and subsequently progressed to respiratory failure due to upper airway swelling and early-onset pulmonary infection, which were treated with protective ventilation and antimicrobial agents. This patient was extubated following improvement of edema on bronchoscopy. Patient MA, an asthmatic, exhibited carbon monoxide poisoning and bronchospasm and was treated with normobaric hyperoxia, bronchodilators, and corticosteroids. The length of stay in the intensive care unit varied from four to 10 days, and all four patients exhibited satisfactory functional recovery. To conclude, inhalation injury has a preponderant role in fires in confined spaces. Invasive ventilation should not be delayed in cases with significant airway swelling. Hyperoxia should be induced early as a therapeutic means against carbon monoxide poisoning, in addition to empiric pharmacological treatment in suspected cases of cyanide poisoning.

Lung hyperinflation by mechanical ventilation versus isolated tracheal aspiration in the bronchial hygiene of patients undergoing mechanical ventilation

OBJECTIVE

To determine the efficacy of lung hyperinflation maneuvers via a mechanical ventilator compared to isolated tracheal aspiration for removing secretions, normalizing hemodynamics and improving lung mechanics in patients on mechanical ventilation.

METHODS

This was a randomized crossover clinical trial including patients admitted to the intensive care unit and on mechanical ventilation for more than 48 hours. Patients were randomized to receive either isolated tracheal aspiration (Control Group) or lung hyperinflation by mechanical ventilator (MVH Group). Hemodynamic and mechanical respiratory parameters were measured along with the amount of aspirated secretions.

RESULTS

A total of 50 patients were included. The mean age of the patients was 44.7 ± 21.6 years, and 31 were male. Compared to the Control Group, the MVH Group showed greater aspirated secretion amount (3.9g versus 6.4g, p = 0.0001), variation in mean dynamic compliance (-1.3 ± 2.3 versus -2.9 ± 2.3; p = 0.008), and expired tidal volume (-0.7 ± 0.0 versus -54.1 ± 38.8, p = 0.0001) as well as a significant decrease in peak inspiratory pressure (0.2 ± 0.1 versus 2.5 ± 0.1; p = 0.001).

CONCLUSION

In the studied sample, the MVH technique led to a greater amount of aspirated secretions, significant increases in dynamic compliance and expired tidal volume and a significant reduction in peak inspiratory pressure.

Performance of noninvasive ventilation in acute respiratory failure in critically ill patients: a prospective, observational, cohort study

BACKGROUND

Noninvasive ventilation (NIV) is used in critically ill patients with acute respiratory failure (ARF) to avoid endotracheal intubation. However, the impact of NIV use on ARF patient's outcomes is still unclear. Our objectives were to evaluate the rate of NIV failure in hypoxemic patients with an arterial carbon dioxide partial pressure (PaCO2) < 45 mmHg or ≥ 45 mmHg at ICU admission, the predictors of NIV failure, ICU and hospital length of stay and 28-day mortality.

METHODS

Prospective single center cohort study. All consecutive patients admitted to a mixed ICU during a three-month period who received NIV, except for palliative care purposes, were included in this study. Demographic data, APACHE II score, cause of ARF, number of patients that received NIV, incidence of NIV failure, length of ICU, hospital stay and mortality rate were compared between NIV failure and success groups.

RESULTS

Eighty-five from 462 patients (18.4 %) received NIV and 26/85 (30.6 %) required invasive mechanical ventilation. NIV failure patients were comparatively younger (67 ± 21 vs. 77 ± 14 years; p = 0.031), had lower arterial bicarbonate (p = 0.005), lower PaCO2 levels (p = 0.032), higher arterial lactate levels (p = 0.046) and APACHE II score (p = 0.034) compared to NIV success patients. NIV failure occurred in 25.0 % of patients with PaCO2 ≥ 45 mmHg and in 33.3 % of patients with PaCO2 < 45 mmHg (p = 0.435). NIV failure was associated with an increased risk of in-hospital death (OR 4.64, 95 % CI 1.52 to 14.18; p = 0.007) and length [median (IQR)] of ICU [12 days (8-31) vs. 2 days (1-4); p < 0.001] and hospital [30 (19-42) vs. 15 (9-33) days; p = 0.010] stay. Predictors of NIV failure included age (OR 0.96, 95 % CI 0.93 to 0.99; p = 0.007) and APACHE II score (OR 1.13, 95 % CI 1.02 to 1.25; p = 0.018).

CONCLUSION

NIV failure was associated with an increased risk of in-hospital death, ICU and hospital stay and was not affected by baseline PaCO2 levels. Patients that failed were comparatively younger and had higher APACHE II score, suggesting the need for a careful selection of patients that might benefit from NIV. A well-designed study on the impact of a short monitored NIV trial on outcomes is needed.

Influence of different degrees of head elevation on respiratory mechanics in mechanically ventilated patients

OBJECTIVE

The positioning of a patient in bed may directly affect their respiratory mechanics. The objective of this study was to evaluate the respiratory mechanics of mechanically ventilated patients positioned with different head angles hospitalized in an intensive care unit.

METHODS

This was a prospective physiological study in which static and dynamic compliance, resistive airway pressure, and peripheral oxygen saturation were measured with the head at four different positions (0° = P1, 30° = P2, 45° = P3, and 60° = P4). Repeated-measures analysis of variance (ANOVA) with a Bonferroni post-test and Friedman analysis were used to compare the values obtained at the different positions.

RESULTS

A comparison of the 35 evaluated patients revealed that the resistive airway pressure values in the 0° position were higher than those obtained when patients were positioned at greater angles. The elastic pressure analysis revealed that the 60° position produced the highest value relative to the other positions. Regarding static compliance, a reduction in values was observed from the 0° position to the 60° position. The dynamic compliance analysis revealed that the 30° angle produced the greatest value compared to the other positions. The peripheral oxygen saturation showed little variation, with the highest value obtained at the 0° position.

CONCLUSION

The highest dynamic compliance value was observed at the 30° position, and the highest oxygenation value was observed at the 0° position.