Assisted Mechanical Ventilation Research Articles

Risperidone induce recurrence of severe acute respiratory distress in a patient with psychotic disorders

Mrs. R, 61-years-old was admitted into the department on July 2015 with a history of major paranoid psychosis. Notion of asthma was indicated in the medical file without any specific treatment. At the admission she received risperidone 4 mg/day and duloxetine since one year. Between October 2015 and June 2016, the patient presented 19 episodes of respiratory decompensation, six of them required transfer in the emergency unit, and 3 in the intensive care unit (ICU) with the assistance of mechanical ventilation. During the last episode, transfer in the intensive care unit was refused by the ICU physician because of the high frequency of recurrence and the difficulty to extube the patient. “End of life” was therefore considered. Nevertheless, medical physician in charge of the patient decided to continue symptomatic treatment and to stop all anti-psychotic drugs susceptible to deteriorate respiratory disease. On the first day we observed a dramatic improvement and no recurrence occurred since now 3 months without any treatment. Between the admission and the occurrence of respiratory decompensation, hypereosinophilia (1610/mL) was observed with recovery in normal value after interruption of risperidone. We also noted an improvement of functional respiratory test. In conclusion, risperidone is an anti-psychotic drug largely used. Severe side effect may endanger life-threatening as described in this case. The recurrence of severe acute respiratory distress without induced factors founded needs to discuss the potential role of this drug.Disclosure of interestThe authors have not supplied their declaration of competing interest.

The respiratory physiotherapy causes pain in newborns? A systematic review

Abstract Introduction: Neonatal respiratory physicaltherapy plays an important role in prevention and treatment of respiratory pathologies. In preterm neonates, immaturity of respiratory system can let development of various respiratory diseases. Meanwhile, it is discussed if respiratory physiotherapy can cause pain. Objective: Investigate presence of pain in neonates undergone to respiratory physiotherapy by a systematic review. Methods: Scientific search in electronic databases: Medline, Lilacs, Bireme, PEDro, Pubmed, Scielo and Capes thesis and dissertations base. Portuguese, English and Spanish, publication year from 2000 to 2012. Results: Thriteen studies were included, but one of them was excluded due to fulltext unavaiable. Therefore, twelve articles were included, nine (81,8%) confirm pain in newborn (NB), from these, in eight (72,7%) intervention was suction and in only one vibrocompression. Four articles studied term and premature newborns. Mechanical ventilatory assistance was used in seven of the studies analyzed. Conclusion: Results suggest that suction and vibrocompression were pain causers in NB. However, evidenced the necessity of well delineated methods to evaluate if physicaltherapy techniques can cause pain in neonates.

Bronchoscopic Management of Tracheobronchial Stenosis Secondary to Granulomatosis with Polyangitis: A Case Report

Airway manifestations of Granulomatosis with Polyangitis (GPA) can be varied ranging from simple mucosal inflammation to critical tracheobronchial stenosis. Management of critical airway stenosis secondary to GPA is challenging. Significant airway compromise might require immediate evaluation and endoscopic or surgical intervention. Endoscopic interventions either in the form of balloon dilatation, electrosurgery, laser therapy, intralesional corticosteroid injection, topical application of mitomycin C, endoluminal spray cryotherapy or stent placement, remain the mainstay of treatment especially in patients who are deemed high risk and not a candidate for reconstructive surgery. We describe a case of tracheobronchial stenosis secondary to GPA, presenting with respiratory insufficiency requiring mechanical ventilator assistance on tracheostomy, successfully managed by endoscopic intervention combining bronchoscopic balloon dilatation and airway stent placement.

A risk score to predict the incidence of prolonged air leak after video-assisted thoracoscopic lobectomy: An analysis from the European Society of Thoracic Surgeons database

ObjectiveThe study objective was to develop an aggregate risk score for predicting the occurrence of prolonged air leak after video-assisted thoracoscopic lobectomy from patients registered in the European Society of Thoracic Surgeons database. MethodsA total of 5069 patients who underwent video-assisted thoracoscopic lobectomy (July 2007 to August 2015) were analyzed. Exclusion criteria included sublobar resections or pneumonectomies, lung resection associated with chest wall or diaphragm resections, sleeve resections, and need for postoperative assisted mechanical ventilation. Prolonged air leak was defined as an air leak more than 5 days. Several baseline and surgical variables were tested for a possible association with prolonged air leak using univariable and logistic regression analyses, determined by bootstrap resampling. Predictors were proportionally weighed according to their regression estimates (assigning 1 point to the smallest coefficient). ResultsProlonged air leak was observed in 504 patients (9.9%). Three variables were found associated with prolonged air leak after logistic regression: male gender (P < .0001, score = 1), forced expiratory volume in 1 second less than 80% (P < .0001, score = 1), and body mass index less than 18.5 kg/m2 (P < .0001, score = 2). The aggregate prolonged air leak risk score was calculated for each patient by summing the individual scores assigned to each variable (range, 0-4). Patients were then grouped into 4 classes with an incremental risk of prolonged air leak (P < .0001): class A (score 0 points, 1493 patients) 6.3% with prolonged air leak, class B (score 1 point, 2240 patients) 10% with prolonged air leak, class C (score 2 points, 1219 patients) 13% with prolonged air leak, and class D (score >2 points, 117 patients) 25% with prolonged air leak. ConclusionsAn aggregate risk score was created to stratify the incidence of prolonged air leak after video-assisted thoracoscopic lobectomy. The score can be used for patient counseling and to identify those patients who can benefit from additional intraoperative preventative measures.

Early Enteral Combined with Parenteral Nutrition Treatment for Severe Traumatic Brain Injury: Effects on Immune Function, Nutritional Status and Outcomes.

Objective To compare the conjoint effect of enteral nutrition (EN) and parenteral nutrition (PN) with single EN or PN on immune function, nutritional status, complications and clinical outcomes of patients with severe traumatic brain injury (STBI). Methods A prospective randomized control trial was carried out from January 2009 to May 2012 in Neurological Intensive Care Unit (NICU). Patients of STBI who met the enrolment criteria (Glasgow Coma Scale score 6~8; Nutritional Risk Screening ≥3) were randomly divided into 3 groups and were admi- nistrated EN, PN or EN+PN treatments respectively. The indexes of nutritional status, immune function, complications and clinical outcomes were examined and compared statistically. Results There were 120 patients enrolled in the study, with 40 pationts in each group. In EN+PN group, T lymthocyte subsets CD3+%, CD4+%, ratio of CD3+/CD25+, ratio of CD4+/CD8+, the plasma levels of IgA, IgM, and IgG at 20 days after nutritional treatment were significantly increased compared to the baseline(t=4.32-30.00, P<0.01), and they were significantly higher than those of PN group (t=2.44-14.70; P<0.05,or P<0.01) with exception of CD4+/CD8+, higher than those of EN group (t=2.49-13.31, P<0.05, or P<0.01) with exceptions of CD3+/CD25+, CD4+/CD8+, IgG and IgM. For the nutritional status, the serum total protein, albumin, prealbumin and hemoglobin were significantly higher in the EN (t=5.87-11.91; P<0.01) and EN+PN groups (t=6.12-13.12; P<0.01) than those in PN group after nutrition treatment. The serum prealbumin was higher in EN+PN group than that in EN group (t=2.08; P<0.05). Compared to the PN group, the complication occurrence rates of EN+PN group were significantly lower in stress ulcer (22.5% vs. 47.5%; χ2= 8.24, P<0.01), intracranial infection (12.5% vs 32.5%;χ2= 6.88, P<0.01) and pyemia (25.0% vs. 47.5%; χ2= 6.57, P<0.05). Compared to the EN group, the complication occurrence rates of EN+PN group were significantly lower in aspirated pneumonia (27.5% vs. 50.0%; χ2= 6.39, P<0.05), hypoproteinemia (17.5% vs. 55.0%; χ2= 18.26, P<0.01) and diarrhea (20.0% vs. 60.0%; χ2= 20.00, P<0.01). The EN+PN group also had significant less length of stay in NICU (t=2.51, 4.82; P<0.05, P<0.01), number of patients receiving assisted mechanical ventilation (χ2= 6.08, 12.88; P<0.05, P<0.01) and its durations (t=3.41, 9.08; P<0.05, P<0.01), and the death rate (χ2=7.50, 16.37; P<0.05, P<0.01) than those of EN or PN group. Conclusion Early EN+PN treatment could promote the recovery of the immune function, enhance nutritional status, decrease complications and improve the clinical outcomes in patients with severe traumatic brain injury.

Ventilatory Support and Management of Secretions in Amyotrophic Lateral Sclerosis

The term amyotrophic lateral sclerosis (ALS) comprises a group of motor neuron diseases which are characterized by rapid disease progression and poor prognosis which is mostly due to severe respiratory muscle weakness and its sequelae. Since causative treatment options are limited it is crucial to offer comprehensive symptomatic therapies to affect patients. Symptoms of respiratory muscle weakness, sleep-disordered breathing and, subsequently, chronic hypercapnic respiratory failure are known to severely affect health-related quality of life and social functioning of patients with ALS. This review article delineates the clinical presentation of respiratory muscle weakness, diagnostic procedures to assess diaphragmatic function, and practical aspects of both mechanical ventilation and cough assistance, respectively. Various technical and electrophysiological methods allow for detection of diaphragmatic weakness and nocturnal hypoventilation. These include spiro-manometric tests of respiratory muscle strength, cardiorespiratory polygraphy and polysomnography, transcutaneous capnography, and blood gas analysis. Once the diagnosis of respiratory muscle weakness is established, non-invasive ventilation, tracheostomy-invasive ventilation (if the patient agrees to it), and management of secretions all become increasingly important in the course of the disease.

Assessment of diaphragmatic dysfunction in the critically ill patient with ultrasound: a systematic review.

Diaphragmatic dysfunction (DD) has a high incidence in critically ill patients and is an under-recognized cause of respiratory failure and prolonged weaning from mechanical ventilation. Among different methods to assess diaphragmatic function, diaphragm ultrasonography (DU) is noninvasive, rapid, and easy to perform at the bedside. We systematically reviewed the current literature assessing the usefulness and accuracy of DU in intensive care unit (ICU) patients. Pubmed, Cochrane Database of Systematic Reviews, Embase, Scopus, and Google Scholar Databases were searched for pertinent studies. We included all original, peer-reviewed studies about the use of DU in ICU patients. Twenty studies including 875 patients were included in the final analysis. DU was performed with different techniques to measure diaphragmatic inspiratory excursion, thickness of diaphragm (Tdi), and thickening fraction (TF). DU is feasible, highly reproducible, and allows one to detect diaphragmatic dysfunction in critically ill patients. During weaning from mechanical ventilation and spontaneous breathing trials, both diaphragmatic excursion and diaphragmatic thickening measurements have been used to predict extubation success or failure. Optimal cutoffs ranged from 10 to 14mm for excursion and 30-36% for thickening fraction. During assisted mechanical ventilation, diaphragmatic thickening has been found to be an accurate index of respiratory muscles workload. Observational studies suggest DU as a reliable method to assess diaphragm atrophy in patients undergoing mechanical ventilation. Current literature suggests that DU could be a useful and accurate tool to detect diaphragmatic dysfunction in critically ill patients, to predict extubation success or failure, to monitor respiratory workload, and to assess atrophy in patients who are mechanically ventilated.

Fluid balance and length of mechanical ventilation in children admitted to a single Pediatric Intensive Care Unit.

Associations between cumulative fluid balance and a prolonged duration of assisted mechanical ventilation have been described in adults. The aim of this study was to evaluate whether fluid balance in the first 48 hours of assisted mechanical ventilation initiation was associated with a prolonged duration of this process among children in the Pediatric Intensive Care Unit (PICU). Retrospective cohort of patients in the PICU o, Hospital Italiano de Buenos Aires, between 1/1/2010 and 6/30/2012. Balance was calculated in percentage of body weight; prolonged mechanical ventilation was defined as >7 days, and confounders were registered. Univariate and multivariate analyses were performed. Two hundred and forty-nine patients were mechanically ventilated for over 48 hours; 163 were included in the study. Balance during the first 48 hours of mechanical ventilation was 5.7% ± 5.86; 82 patients (50.3%) were on mechanical ventilation for more than 7 days. Age 〈 4 years old (OR 3.21, 95% CI 1.38-7.48, p 0.007), respiratory disease (OR 4.94, 95% CI 1.51-16.10, p 0.008), septic shock (OR 4.66, 95% CI 1.10-19.65, p 0.036), Pediatric Logistic Organ Dysfunction (PELOD) 〉 10 (OR 2.44, 95% CI 1.234.85, p 0.011), and positive balance 〉 13% (OR 4.02, 95% CI 1.08-15.02, p 0.038) were associated with prolonged mechanical ventilation. The multivariate model resulted in an OR 2.58, 95% CI: 1.17-5.58, p= 0.018 for PELOD 〉 10, and an OR 3.7, 95% CI: 0.91-14.94, p= 0.066 for positive balance 〉 13%. Regarding prolonged mechanical ventilation, the multivariate model showed an independent association with organ dysfunction (PELOD 〉 10) and a trend towards an association with positive balance 〉 13%.

A philosophical assessment of TK's autopsy report: Implications for the debate over the brain death criteria.

Traditionally, the presence or absence of bodily integration has been used to definitively discern the presence or absence of life in the human being where decomposition of the body is the surest sign of death. The autopsy report of a patient named TK who was brain-dead for nearly twenty years demonstrates that brain-dead patients retain their bodily integrity. As such, TK and other brain-dead patients are not dead. They are living, though severely disabled, human organisms, who are human persons made in the image and likeness of God.

Assisted Ventilation in Patients With Acute Respiratory Distress Syndrome

BACKGROUND: In patients with acute respiratory distress syndrome (ARDS), the use of assisted mechanical ventilation is a subject of debate. Assisted ventilation has benefits over controlled ventilation, such as preserved diaphragm function and improved oxygenation. Therefore, higher level of patient of ventilator assist may be preferable in ARDS. However, assisted modes may also increase the risk of high tidal volumes and lung-distending pressures. The current study aims to quantify how differences in freedom to control the ventilator affect lung-protective ventilation, breathing pattern variability, and patient-ventilator interaction. METHODS: Twelve patients with ARDS were ventilated in a randomized order with assist pressure control ventilation (PCV), pressure support ventilation (PSV), and neurally adjusted ventilatory assist (NAVA). Transpulmonary pressure, tidal volume, diaphragm electrical activity, and patient-ventilator interaction were measured. Respiratory variability was assessed using the coefficient of variation of tidal volume. RESULTS: During inspiration, transpulmonary pressure was slightly lower with NAVA (10.3 +/- 0.7, 11.2 +/- 0.7, and 9.4 +/- 0.7 cm H2O for PCV, PSV, and NAVA, respectively; P < 0.01). Tidal volume was similar between modes (6.6 [5.7 to 7.0], 6.4 [5.8 to 7.0], and 6.0 [5.6 to 7.3] ml/kg for PCV, PSV, and NAVA, respectively), but respiratory variability was higher with NAVA (8.0 [6.4 to 10.0], 7.1 [5.9 to 9.0], and 17.0 [12.0 to 36.1] % for PCV, PSV, and NAVA, respectively; P < 0.001). Patient-ventilator interaction improved with NAVA (6 [5 to 8] % error) compared with PCV (29 [14 to 52] % error) and PSV (12 [9 to 27] % error); P < 0.0001. CONCLUSION: In patients with mild-to-moderate ARDS, increasing freedom to control the ventilator maintains lung-protective ventilation in terms of tidal volume and lung-distending pressure, but it improves patient-ventilator interaction and preserves respiratory variability.

Driving pressure during assisted mechanical ventilation: Is it controlled by patient brain?

Tidal volume (VT) is the controlled variable during passive mechanical ventilation (CMV) in order to avoid ventilator-induced-lung-injury. However, recent data indicate that the driving pressure [ΔP; VT to respiratory system compliance (Crs) ratio] is the parameter that best stratifies the risk of death. In order to study which variable (VT or ΔP) is controlled by critically ill patients, 108 previously studied patients were assigned to receive PAV+ (a mode that estimates Crs and permits the patients to select their own breathing pattern) after CMV, were re-analyzed. When patients were switched from CMV to PAV+ they controlled ΔP without constraining VT to narrow limits. VT was increased when the resumption of spontaneous breathing was associated with an increase in Crs. When ΔP was high during CMV, the patients (n=12) decreased it in 58 out of 67 measurements. We conclude that critically ill patients control the driving pressure by sizing the tidal volume to individual respiratory system compliance using appropriate feedback mechanisms aimed at limiting the degree of lung stress.

Piper Study Rationale and Design: Characterizing the Incidence of Acute Respiratory Distress Syndrome in Hematology-Oncology Patients Following the Transfusion of Conventional or Pathogen-Reduced Platelet Components

The INTERCEPT™ Blood System (amotosalen + UVA illumination) for platelets is FDA-approved in the USA for the ex vivo preparation of pathogen-reduced, apheresis platelet components (PCs) to reduce transfusion-transmitted infection, including sepsis, and to potentially reduce the risk of transfusion-associated graft vs. host disease. Platelet transfusion is a potential risk factor for acute respiratory distress syndrome (ARDS), but the incidence of ARDS following platelet transfusion is not well-defined. A phase 3 study (SPRINT) of patients treated with INTERCEPT PCs vs. conventional PCs reported a frequency of ARDS of 1.6% vs. 0%, respectively (Snyder et al., Transfusion 2005;45:1864-1875). This unexpectedly low incidence of ARDS, owing to the lack of precise definitions, prompted the conduct of a blinded reanalysis using the American European Consensus Criteria for ARDS. Reanalysis demonstrated a frequency of ARDS of 6.0% and 4.9% for recipients of pathogen-reduced PCs and conventional PCs, respectively, with no significant treatment difference between groups (Corash et al., Blood 2011;117:1014-1020). Large scale active hemovigilance programs in Europe conducted by regulatory authorities from 2009-2014 reported no differences in the incidence of ARDS following platelet transfusion (0.33 vs. 0.32 cases per 10,000 platelets transfused). To evaluate the incidence of severe pulmonary adverse events requiring assisted ventilation in hematology-oncology (heme/onc) patients following the transfusion of apheresis derived INTERCEPT PCs compared to transfusion of conventional apheresis PCs. A prospective, non-randomized sequential cohort, open label, multi-center, non-inferiority, phase 4 surveillance study following transfusion of INTERCEPT PCs will be conducted. The patient population will be heme/onc hematopoietic stem cell transplant (HSCT) patients expected to require >1 PC transfusions. The proportion of patients requiring treatment-emergent assisted mechanical ventilation (TEAMV) during the observation period as defined by intubation or tight-fitting mask. TEAMV provides an objective measure of severe, clinically significant pulmonary injury. Patients will be assessed for TEAMV within 7 days after each study PC transfusion. 3000 patients allow for >90% power (one-sided alpha 0.025) for a non-inferiority margin of 0.023, assuming an event rate of 3.7% for the Control group. Events will be adjudicated by a blinded Pulmonary Expert Adjudication Panel. The PIPER study will address a significant deficit in the understanding of serious pulmonary events in heme/onc HSCT patients who require platelet support. It will be the first large controlled trial designed and powered to detect serious pulmonary adverse events in this patient population.

Transfusion related acute lung injury in a perinatal woman

We report the case of a 26-year-old female who underwent emergency caesarean section at a private hospital and was referred to the Government Maternity Hospital (GMH), Tiruapti for bleeding per vaginum 4 hours after delivery. She had received one unit of whole blood transfusion outside. Later, whole blood, platelets (n= 1 unit) and fresh frozen plasma (n= 2 units) were transfused over a period of 6 hours at GMH, Tirupati. Two hours there after, she complained of sudden breathlessness with cough. On examination, bilateral basal crepitations and wheezing were noted. Fall in oxygen saturation by pulse oximetry, hypotension, tachypnoea and mild fever were also noted. Chest radiograph showed bilateral frontal opacities. Possibility of transfusion-related acute lung injury (TRALI) was considered. Supportive treatment included supplemental oxygen through oxygen mask followed by assisted mechanical ventilation and the patient improved. The present case highlights the importance of transfusion related adverse events so as to facilitate prompt recognition and appropriate treatment at the right time.

Assisted Ventilation

Controlled Mechanical Ventilation may be essential in the setting of severe respiratory failure but consequences to the patient including increased use of sedation and neuromuscular blockade may contribute to delirium, atelectasis, and diaphragm dysfunction. Assisted ventilation allows spontaneous breathing activity to restore physiological displacement of the diaphragm and recruit better perfused lung regions. Pressure Support Ventilation is the most frequently used mode of assisted mechanical ventilation. However, this mode continues to provide a monotonous pattern of support for respiration which is normally a dynamic process. Noisy Pressure Support Ventilation where tidal volume is varied randomly by the ventilator may improve ventilation and perfusion matching but the degree of support is still determined by the ventilator. Two more recent modes of ventilation, Proportional Assist Ventilation and Neurally Adjusted Ventilatory Assist (NAVA), allow patient determination of the pattern and depth of ventilation. Proposed advantages of Proportional Assist Ventilation and NAVA include decrease in patient ventilator asynchrony and improved adaptation of ventilator support to changing patient demand. Work of breathing can be normalized with these modes as well. To date, however, a clear pattern of clinical benefit has not been demonstrated. Existing challenges for both of the newer assist modes include monitoring patients with dynamic hyperinflation (auto-positive end expiratory pressure), obstructive lung disease, and air leaks in the ventilator system. NAVA is dependent on consistent transduction of diaphragm activity by an electrode system placed in the esophagus. Longevity of effective support with this technique is unclear.

Mechanical ventilatory assistance may reduce dyspnea during walking especially in patients with impaired cardiopulmonary function early after cardiovascular surgery

BackgroundTo determine which patients effectively respond to ventilatory assistance (VA) and to examine the factors influencing patient response in patients who underwent cardiovascular (CV) surgery. MethodsWe conducted the first walking session after surgery either with or without VA in a randomized order. The patients walked with 3cmH2O of inspiratory pressure support. We measured dyspnea and leg fatigue during initial walking either with or without VA by using a modified Borg scale. Ventilatory parameters were measured by mechanical ventilation before and immediately after walking. Lung function and maximal inspiratory pressure (MIP) were measured and chest radiographs were analyzed by the same cardiac surgeon on the same day as walking. ResultsFrom the total of 74 patients who underwent CV surgery, 56 patients were successively enrolled in the study. Thirty-five out of 56 patients had dyspnea and 18 patients (30% of the total patients) effectively responded to VA (responders). Minute ventilation/estimated maximum voluntary ventilation immediately after walking significantly decreased with VA, and MIP was lower in responders than in non-responders after surgery. The responders revealed greater pulmonary edema scores than non-responders. ConclusionsThe findings of the present study suggest that VA may possibly facilitate successful mobilization early after CV surgery, especially in patients with impaired cardiopulmonary function.

The effects of a 2-h trial of high-flow oxygen by nasal cannula versus Venturi mask in immunocompromised patients with hypoxemic acute respiratory failure: a multicenter randomized trial.

IntroductionIn immunocompromised patients, acute respiratory failure (ARF) is associated with high mortality, particularly when invasive mechanical ventilation (IMV) is required. In patients with severe hypoxemia, high-flow nasal oxygen (HFNO) therapy has been used as an alternative to delivery of oxygen via a Venturi mask. Our objective in the present study was to compare HFNO and Venturi mask oxygen in immunocompromised patients with ARF.MethodsWe conducted a multicenter, parallel-group randomized controlled trial in four intensive care units. Inclusion criteria were hypoxemic ARF and immunosuppression, defined as at least one of the following: solid or hematological malignancy, steroid or other immunosuppressant drug therapy, and HIV infection. Exclusion criteria were hypercapnia, previous IMV, and immediate need for IMV or noninvasive ventilation (NIV). Patients were randomized to 2 h of HFNO or Venturi mask oxygen.ResultsThe primary endpoint was a need for IMV or NIV during the 2-h oxygen therapy period. Secondary endpoints were comfort, dyspnea, and thirst, as assessed hourly using a 0–10 visual analogue scale. We randomized 100 consecutive patients, including 84 with malignancies, to HFNO (n = 52) or Venturi mask oxygen (n = 48). During the 2-h study treatment period, 12 patients required IMV or NIV, and we found no significant difference between the two groups (15 % with HFNO and 8 % with the Venturi mask, P = 0.36). None of the secondary endpoints differed significantly between the two groups.ConclusionsIn immunocompromised patients with hypoxemic ARF, a 2-h trial with HFNO improved neither mechanical ventilatory assistance nor patient comfort compared with oxygen delivered via a Venturi mask. However, the study was underpowered because of the low event rate and the one-sided hypothesis.Trial registrationClinicalTrials.gov identifier: NCT02424773. Registered 20 April 2015.

Impact of The Assist Ventilation Mode On Work of Breathing (Wob): Neurally Adjusted Ventilatory Assist (Nava) Versus Pressure Support Ventilation (Psv) Versus Proportional Assist Ventilation Plus (Pav+)

During assisted mechanical ventilation, appropriate WOB prevents diaphragm atrophy and fastens weaning. During PSV the ventilator support is fixed, irrespective of the patient's effort. On the contrary, both the NAVA and PAV + algorithms are designed to amplify patient's spontaneous effort. [1], [2]

Intravenous nanosomes of quercetin improve brain function and hemodynamic instability after severe hypoxia in newborn piglets

Perinatal asphyxia is a major cause of death and neurological morbidity in newborns and oxidative stress is one of the critical mechanisms leading to permanent brain lesions in this pathology. In this context we have chosen quercetin, a natural antioxidant, known also by its brain protective effects to study its potential as a therapy for brain pathology provoked by severe hypoxia in the brain. To overcame the difficulties of quercetin to access the brain, we have developed lecithin/cholesterol/cyclodextrin nanosomes as a safe and protective vehicle.We have applied the nanosomal preparation intravenously to newborn piglets submitted to a severe hypoxic or ischemic/hypoxic episode and followed them for 8 or 72 h, respectively. Either towards the end of 8 h after hypoxia or up to 72 h after, electroencephalographic amplitude records in animals that received the nanosomes improved significantly. Animals receiving quercetin also stabilized blood pressure and recovered spontaneous breathing. In this experimental group mechanical ventilation assistance was withdrawn in the first 24 h while the hypoxic and vehicle groups required more than 24 h of mechanical ventilation. Three days after the hypoxia the suckling and walking capacity in the group that received quercetin recovered significantly compared with the hypoxic groups. Pathological studies did not show significant differences in the brain of newborn piglets treated with nanosomes compared with hypoxic groups. The beneficial effects of quercetin nanosomal preparation after experimental perinatal asphyxia show it as a promising putative treatment for the damaged brain in development.

Index of Suspicion in the Nursery

A male infant is born at 324/7 weeks of gestation with a birth weight of 2,870 g. He is born to a 27-year-old gravida 2, para 1001 mother who received appropriate prenatal care. The infant is noted to have severe isolated abdominal ascites on a 21-week ultrasonogram, which is confirmed with subsequent ultrasonography. No pleural or pericardial effusion, skin edema, or structural abnormalities in the heart are noted. Doppler ultrasonography reveals normal middle cerebral artery velocity. The mother’s blood group is O+, antibody test result is negative, and serologic test results for hepatitis B, human immunodeficiency virus, and syphilis are negative. The mother is rubella immune and tests group B Streptococcus negative. The results of Neisseria gonorrhea and Chlamydia tests are negative. IgM test results are negative for toxoplasma, parvovirus, varicella zoster virus, and cytomegalovirus. The mother presents with premature rupture of the membranes, which occurs 16 hours before delivery, and receives 2 doses of betamethasone. Before an elective low transverse caesarean delivery, 1.5 L of clear fluid is removed through amniocentesis and 180 mL through paracentesis secondary to concerns of fetal lung immaturity and abdominal distension. The infant is electively intubated at delivery in anticipation of respiratory distress from extensive ascites, administered one dose of surfactant, and given mechanical ventilatory assistance. Apgar scores are 6 and 8 at 1 and 5 minutes, respectively. The infant passes urine and meconium soon after birth. On physical examination, the infant is noted to have a distended abdomen and bilateral scrotal edema. Cord arterial and venous blood gas …

Assisted mechanical ventilation: the future is now!

Assisted ventilation is a highly complex process that requires an intimate interaction between the ventilator and the patient. The complexity of this form of ventilation is frequently underappreciated by the bedside clinician. In assisted mechanical ventilation, regardless of the specific mode, the ventilator’s gas delivery pattern and the patient’s breathing pattern must match near perfectly or asynchrony between the patient and the ventilator occurs. Asynchrony can be categorized into four general types: flow asynchrony; trigger asynchrony; cycle asynchrony; and mode asynchrony. In an article recently published in BMC Anesthesiology, Hodane et al. have demonstrated reduced asynchrony during assisted ventilation with Neurally Adjusted Ventilatory Assist (NAVA) as compared to pressure support ventilation (PSV). These findings add to the growing volume of data indicating that modes of ventilation that provide proportional assistance to ventilation – e.g., NAVA and Proportional Assist Ventilation (PAV) – markedly reduce asynchrony. As it becomes more accepted that the respiratory center of the patient in most circumstances is the most appropriate determinant of ventilatory pattern and as the negative outcome effects of patient-ventilator asynchrony become ever more recognized, we can expect NAVA and PAV to become the preferred modes of assisted ventilation!