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This article discusses the importance of resuscitation guidelines in improving outcomes for cardiac arrest patients. It highlights the evolution of these guidelines over time, with a shift towards prioritizing circulation through prompt cardiopulmonary resuscitation (CPR) over airway management. The article also presents findings from a study that used thoracic bioimpedance technology to measure the effectiveness of bag-valve-mask ventilation during resuscitation efforts. The study found that adequate ventilation was associated with higher rates of survival and favorable neurological outcomes. While the study has some limitations, it suggests that attention to each aspect of resuscitation, including ventilation, may be crucial in saving more lives. [Extracted from the article]

For extubation in pediatric patients, the evaluation of readiness is strongly recommended. However, a device or practice that is superior to clinical judgment has not yet been accurately determined. Thus, it is important to conduct a review on the techniques of choice in clinical practice to predict extubation failure in pediatric patients. Based on a search in the PubMed®, Biblioteca Virtual em Saúde, Cochrane Library and Scopus databases, we conducted a survey of the predictive variables of extubation failure most commonly used in clinical practice in pediatric patients. Of the eight predictors described, the three most commonly used were the spontaneous breathing test, the rapid shallow breathing index and maximum inspiratory pressure. Although the disparity of the data presented in the studies prevented statistical treatment, it was still possible to describe and analyze the performance of these tests. [ABSTRACT FROM AUTHOR]

Objective: to verify the association of the spontaneous breathing test with the nursing diagnosis of Dysfunctional Ventilatory Weaning Response (00034) and to identify the accuracy measures of the spontaneous breathing test for the nursing diagnosis. Method: a cross-sectional study conducted with 42 patients in critical care. Fischer's exact test verified the association, and the accuracy measures were calculated with Medcalc Software Online®. Results: the association between the test and the diagnosis was significant (p=0.0079). The highlighted accuracy measures were 77.42% specificity (58.90 - 90.41), positive likelihood ratio of 3.22 (1.53 - 6.79), and diagnostic odds ratio of 9.14 (1.90 - 44.01). Conclusion: the study verified the existence of an association between the outcome of the spontaneous breathing test and the Dysfunctional Ventilatory Weaning Response (00034), with statistical significance. It also indicated the adequacy of three accuracy measures for the nursing diagnosis. [ABSTRACT FROM AUTHOR]

International guidelines on neonatal resuscitation were published in 2010 based on the best available evidence. While many of these guidelines remain unchanged, subtle refinements have evolved with recent evidence. The aim of this review is to distill these recommendations, to provide updates where appropriate, and to condense them into a framework that is useful for the clinician. Birth depression is a common event, caused by both maternal and neonatal conditions. Prompt initiation of the most appropriate support is essential for achieving best outcomes. While ventilation of the small airways is the most important intervention in the neonatal resuscitation algorithm, progression to the next step is based on the simultaneous assessment of both heart rate and respirations. Serial clinical assessment of the response to interventions is fundamental to a successful resuscitation. Pulse oximetry should be used for assessing oxygenation when resuscitation is required. And generally speaking, term and near-term infants should be resuscitated using room air, while preterm infants should be resuscitated with the lowest concentration of oxygen needed to maintain normal oxygen saturations. Decisions regarding respiratory support should be individualized, but the lowest peak inspiratory pressure needed to achieve clinical improvement is advocated in neonatal resuscitation. The use of end-expiratory pressure reduces the need for invasive respiratory support, and support of spontaneous respirations with continuous positive airway pressure (CPAP) has been shown to result in improved long-term outcomes in preterm, but not term infants. Finally, circulatory support is rarely indicated in neonatal resuscitation scenarios, but is recommended in circumstances of presumed volume loss, persistent or prolonged bradycardia, or a persistent, suboptimal response to resuscitative efforts. [ABSTRACT FROM AUTHOR]

HPS is a life-threatening condition in patients with end-stage liver disease, in which intrapulmonary vascular dilatations result in intrapulmonary shunts and hypoxemia. The only successful treatment is liver transplantation. Hypoxemia may be severe prior to transplantation; however, it can worsen or become refractory after liver transplantation and result in increased post-operative mortality. Here, we present the case of a 10-month-old female infant with progressive end-stage liver disease and severe HPS, who developed refractory hypoxemia after a successful liver transplantation. After 19 days of unsuccessful attempts to reverse the hypoxemia using conventional mechanical ventilation and HFOV, the patient responded dramatically to APRV, with rapid improvement in her Pa O2 and sharp decline in her OI. She was able to begin weaning from APRV two days later and was extubated within seven days. APRV was successful in treating refractory hypoxemia in this patient with severe HPS after liver transplantation, possibly by modifying distribution of pulmonary blood flow. Although we cannot rule out coincidental natural resolution of the HPS, APRV could be a useful rescue therapy in patients with HPS and refractory hypoxemia. [ABSTRACT FROM AUTHOR]

Purpose: Our objective was to revise the definition of acute respiratory distress syndrome (ARDS) using a conceptual model incorporating reliability and validity, and a novel iterative approach with formal evaluation of the definition. Methods: The European Society of Intensive Care Medicine identified three chairs with broad expertise in ARDS who selected the participants and created the agenda. After 2 days of consensus discussions a draft definition was developed, which then underwent empiric evaluation followed by consensus revision. Results: The Berlin Definition of ARDS maintains a link to prior definitions with diagnostic criteria of timing, chest imaging, origin of edema, and hypoxemia. Patients may have ARDS if the onset is within 1 week of a known clinical insult or new/worsening respiratory symptoms. For the bilateral opacities on chest radiograph criterion, a reference set of chest radiographs has been developed to enhance inter-observer reliability. The pulmonary artery wedge pressure criterion for hydrostatic edema was removed, and illustrative vignettes were created to guide judgments about the primary cause of respiratory failure. If no risk factor for ARDS is apparent, however, objective evaluation (e.g., echocardiography) is required to help rule out hydrostatic edema. A minimum level of positive end-expiratory pressure and mutually exclusive PaO/FiO thresholds were chosen for the different levels of ARDS severity (mild, moderate, severe) to better categorize patients with different outcomes and potential responses to therapy. Conclusions: This panel addressed some of the limitations of the prior ARDS definition by incorporating current data, physiologic concepts, and clinical trials results to develop the Berlin definition, which should facilitate case recognition and better match treatment options to severity in both research trials and clinical practice. [ABSTRACT FROM AUTHOR]

Summary: Aim of the study: Endotracheal intubation is the preferred method to ensure proper artificial ventilation. Early detection of esophageal intubation is important for an individual patient''s outcome. The aim of the study was to see if impedance measurements can be used to detect esophageal intubation, using the impedance measurement system of an experimental defibrillator. Materials and methods: Patients who died at the emergency department of a tertiary care hospital were eligible to be studied. After death was declared, patients were ventilated with a predefined tidal volume alternately via the conventional tracheal tube and via an additionally tube placed into the esophagus. The lowest and respectively highest median impedance amplitude for the first three ventilations was used as cut-off to calculate predictive values. Results: We enrolled 10 patients (mean age 65 years (S.D. 14), 7 male) of whom 9 underwent CPR prior to death, 30% of the patients had a BMI>30. Severe lung-edema was present in 2 cases. The lowest tracheal impedance value was 0.736Ω and the highest esophageal was 0.496Ω. A ROC curve for this individualised approach gave an area under the curve of 1 (95% CI 0.001, 0.249). Conclusion: There is a large and significant reduction in transthoracic impedance when the tube is malpositioned in the esophagus. It may therefore be feasible to detect malintubation via thoracic impedance changes as an aid to improve the survival of critical ill patients. Further investigations on a larger population are needed. [Copyright &y& Elsevier]

Nebulized amikacin may be an attractive option for the treatment of lung infections. Low systemic absorption may permit the use of high doses, leading to high lung concentrations without systemic toxicity. We evaluated the pharmacokinetics and safety of an optimized high-dose amikacin nebulization technique. in vitro and in vivo pharmacokinetic study. Six healthy volunteers (age 21–30 years, weight 49–68 kg). The Aeroneb Pro nebulizer with an Idehaler vertical spacer was evaluated in a bench study. Amikacin was administered intravenously (15 mg/kg) and nebulized (40, 50, and 60 mg/kg) during noninvasive pressure-support ventilation through a mouthpiece. Median (interquartile range) in vitro inhaled fraction was 31% (30–32) and inhalable output was 681 mg/h (630–743). Serum concentrations after nebulization were less than or equal to those after infusion. The area under the serum concentration curve was significantly higher after infusion (138 mg h–1l–1, 122–143) than after nebulization (49 mg h–1l–1, 39–55, at 40 mg/kg; 63, 53–67 at 50; 66, 50–71, at 60). Peak serum concentration was also higher after infusion: 48 mg/l (45–49) after infusion compared to 8.2 (5.6–8.7), 9.2 (7.6–10.2), and 9.2 (5.2–10.3), respectively. Mean absorption times after nebulization were 2 h 24 min (2,07–2,45), 2 h 21 min (2,07–2,35), and 2 h 5 min (2,00–2,25), respectively. No side effect was observed. Nebulization of up to 60 mg/kg amikacin appears to be safe in healthy subjects and associated with lower serum concentrations than a 15 mg/kg infusion. [ABSTRACT FROM AUTHOR]

To avoid ventilator induced lung injury, tidal volume should be low in acute lung injury (ALI). Reducing dead space may be useful, for example by using a pattern of inspiration that prolongs the time available for gas distribution and diffusion within the respiratory zone, the mean distribution time (MDT). A study was conducted to investigate how MDT affects CO2 elimination in pigs at health and after ALI. Randomised crossover study in the animal laboratory of Lund University Biomedical Center. Healthy pigs and pigs with ALI, caused by surfactant perturbation and lung-damaging ventilation were ventilated with a computer-controlled ventilator. With this device each breath could be tailored with respect to insufflation time and pause time ( T I and T P) as well as flow shape (square, increasing or decreasing flow). The single-breath test for CO2 allowed analysis of the volume of expired CO2 and the volume of CO2 re-inspired from Y-piece and tubes. With a long MDT caused by long T I or T P, the expired volume of CO2 increased markedly in accordance with the MDT concept in both healthy and ALI pigs. High initial inspiratory flow caused by a short T I or decreasing flow increased the re-inspired volume of CO2. Arterial CO2 increased during a longer period of short MDT and decreased again when MDT was prolonged. CO2 elimination can be enhanced by a pattern of ventilation that prolongs MDT. Positive effects of prolonged MDT caused by short T I and decreasing flow were attenuated by high initial inspiratory flow. [ABSTRACT FROM AUTHOR]

The authors have previously shown that mechanical ventilation can result in increased pulmonary inflammation and suppressed peripheral leukocyte function. In the present study the effect of surfactant therapy on pulmonary inflammation and peripheral immune function in ventilated surfactant-deficient rats was assessed. Surfactant deficiency was induced by repeated lung lavage, treated rats with surfactant or left them untreated, and ventilated the rats during 2 hours. Nonventilated rats served as healthy control group. Expression of macrophage inflammatory protein (MIP)-2 was measured in bronchoalveolar lavage (BAL), interleukin (IL)-1β, and heat shock protein 70 (HSP70) were measured in total lung homogenates. Outside the lung phytohemagglutinin (PHA)-induced lymphocyte proliferation, interferon (IFN)-γ and IL-10 production, and natural killer activity were measured in splenocytes. After 2 hours of mechanical ventilation, expression of MIP-2, IL-1β, and HSP70 increased significantly in the lungs of surfactant-deficient rats. Outside the lung, mitogen-induced proliferation and production of IFN-γ and IL-10 reduced significantly. Only natural killer cell activity remained unaffected. Surfactant treatment significantly improved lung function, but could not prevent increased pulmonary expression of MIP-2, IL-1β, and HSP70 and decreased peripheral mitogen-induced lymphocyte proliferation and IFN-γ and IL-10 production in vitro. In conclusion, 2 hours of mechanical ventilation resulted in increased lung inflammation and partial peripheral leukocyte suppression in surfactant-deficient rats. Surfactant therapy ameliorated lung function but could not prevent or restore peripheral immunosuppression. The authors postulate that peripheral immunosuppression may occur in ventilated surfactant deficient patients, which may enhance susceptibility for infections. [ABSTRACT FROM AUTHOR]

Prognosis of patients with ischemic stroke requiring mechanical ventilation (MV) has been reported to be poor. However, longterm survival and functional outcome have scarcely been studied and nothing is known about the prevalence of cognitive impairment or depression in survivors and their quality of life (QoL). We identified all patients treated for acute ischemic stroke on a Neurological Intensive Care Unit during 3.5 years who required MV for more than 24 hours. Early mortality rate at 2 months and survival rates at 1 and 2 years were determined. Survivors were examined for functional outcome (modified Rankin Scale (mRS), Barthel Index), cognitive impairment (Mini Mental State Examination (MMSE)), depression (Beck Depression Inventory, BDI) and QoL (Short Form–36). Clinical characteristics on admission were analyzed for prognostic significance. Of 101 consecutive patients, 44% died within 60 days. Survival rates at 1 and 2 years were 40% and 33%, respectively.Age > 60 years (p = 0.002) and Glasgow Coma Scale score < 10 on admission (p = 0.002) were independent predictors of early and late mortality. History of myocardial infarction (p = 0.007) independently predicted late mortality at 2 years. Of 33 surviving patients, nine (27%) had a good functional outcome (mRS 0–2). Of 27 survivors who could be interviewed, 17 (63%) had no cognitive impairment (MMSE > 24) and 20 (74%) did not suffer from relevant depression (BDI < 19). In conclusion, longer–term survival of patients with ischemic stroke requiring MV was 33% and every fourth survivor resumed an independent life without dementia or depression. Older patients comatose on admission and with concomitant cardiovascular disease had the lowest probability of a favorable outcome. [ABSTRACT FROM AUTHOR]

Objective: Invasive aspergillosis is associated with a poor prognosis, especially in critically ill patients with cerebral involvement. We present two cases of cerebral invasive aspergillosis successfully treated in the intensive care unit with combination antifungal therapies and without surgery.Case Presentation: The first patient was a 49-year-old man with rheumatoid arthritis who received corticosteroid and cyclophosphamide treatment and developed pulmonary and cerebral invasive aspergillosis. After failure of voriconazole the patient had a successful outcome with voriconazole and liposomal amphotericin B therapy. The patient returned home after an 8-month hospital stay. The second patient was a 54-year-old woman with pulmonary neoplasia and corticosteroid treatment who developed pulmonary and cerebral invasive aspergillosis. After failure of voriconazole and liposomal amphotericin B therapy the patient had a favorable outcome with liposomal amphotericin B and caspofungin therapy. The patient died 10 months after initial diagnosis of cardiac tamponade unrelated to fungal infection.Discussions: These cases illustrate the improving prognosis of invasive aspergillosis due to the availability of new treatments, especially in cases of cerebral involvement. It also demonstrates that the outcome of critically ill patients requiring mechanical ventilation for invasive aspergillosis can be favorable. The treatment of patients with invasive cerebral aspergillosis in the intensive care setting should be encouraged. [ABSTRACT FROM AUTHOR]

Abstract: The “Guidelines 2000 for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care – International Consensus on Science” recommend a tidal ventilation volume of 10ml/kg body-weight without the use of supplemental oxygen during two-rescuer adult cardiopulmonary resuscitation (CPR). This relates to a ventilation volume of about 6.4l/min. Additionally, the first aid provider ventilating the victim will breathe for him/herself during the external chest compression period adding another 3.2l/min of ventilation. Finally, a deep breath is recommended before each ventilation to increase the end-expiratory oxygen concentration of the air exhaled. To investigate the effects of these recommendations, 20 healthy volunteers were asked to perform two-rescuer CPR in a lung model connected to a BLS-manikin. End-tidal carbon dioxide, oxygen saturation, and heart rate were recorded continuously. Capillary blood gas samples were collected and non-invasive blood pressure was recorded prior to the start of external chest compressions and immediately after the end of each measurment period. Furthermore, hyperventilation related symptoms reported by the volunteers were also recorded. The data reveal a significant decrease in capillary and end-tidal carbon dioxide pressure in the volunteers (P &#60;0.001). Additionally, in 75% of test persons multiple hyperventilation associated symptoms occurred. Ventilation during two-rescuer CPR performed according to the Guidelines 2000 may cause injury to the health of first aid providers. To minimize hyperventilation, both rescuers should exchange their positions at intervals of 3–5min. These data challenge the recommendation to take a deep breath prior to each ventilation. [Copyright &y& Elsevier]

Objective: Use of lung-protective mechanical ventilation (MV) by applying lower tidal volumes is recommended in patients suffering from acute lung injury (ALI) or acute respiratory distress syndrome (ARDS). Recent data suggest that lung-protective MV may benefit non-ALI/ARDS patients as well. This study analyzed tidal volume settings in three ICUs in The Netherlands to determine the effect of feedback and education concerning use of lung-protective MV.Design and Setting: Observational study in one academic and two nonacademic "closed format" ICUs.Patients: Intubated mechanically ventilated subjects.Interventions: Feedback and education concerning lung-protective MV with special attention to the importance of closely adjusting tidal volumes to predicted body weight (PBW).Results: Tidal volumes declined significantly within 6 months after intervention (from 9.8+/-2.0 at baseline to 8.1+/-1.7 ml/kg PBW) as the percentage of undesirable ventilation data points, defined as tidal volumes greater than 8 ml/kg PBW (84% vs. 48%). There were no differences between patients meeting the international definition criteria for ALI/ARDS and those not. Only four patients received tidal volumes less than 6 ml/kg PBW. Lower tidal volumes were still used after 12 months. Tidal volumes in patients on mandatory MV and patients breathing on spontaneous modes were similar.Conclusions: Feedback and education improve physician compliance in use of lung-protective MV. [ABSTRACT FROM AUTHOR]

Objective: Measurements from the pulmonary pressure-volume (PV) curve have been proposed to adjust ventilator settings. We investigated the effects of repeated construction of an inflation PV curve implemented in a standard ventilator on recruitment or derecruitment in acutely injured lungs.Design and Setting: Prospective experimental animal study in eight anesthetized and mechanically ventilated pigs.Interventions: Acute lung injury was induced by lung lavage and animals were ventilated in volume controlled mode with PEEP 10 cmH(2)O. The PV curve was constructed five times repeatedly by constant pressure rise, after which ventilation with the preset PEEP was resumed immediately. Studies of hemodynamics, lung mechanics, blood gases and computed tomography were carried out before and after maneuvers.Measurements and Results: Derecruitment was assessed as an increase in nonaerated lung volume (V(NON)), and V(PEEP) was the end-expiratory volume difference between PEEP and ZEEP. There was a significant decrease in PaO(2) from 90.4+/-33.3 to 70.9+/-36.3 mmHg and a rise in venous admixture from 47.8+/-12.7 to 59.1+/-16.6%. V(PEEP) was reduced from 244 to 202 ml. A corresponding decrease in normally aerated lung volume was observed, while regression analysis revealed increase in V(NON) depending on the amount of preexisting atelectasis.Conclusions: Repeated generation of the PV curve with a readily available tool resulted in worsened oxygenation. Derecruitment of the lungs occurred with loss of PEEP at the start of the maneuver, which could not be recovered by a maximum inflation pressure of 40 cmH(2)O. Repeated use of the investigated tool should be cautioned, and users should consider measures to preserve aerated lung volumes. [ABSTRACT FROM AUTHOR]

Context Inhaled nitric oxide has been shown to improve oxygenation in acute lung injury. Objective To evaluate the clinical efficacy of low-dose (5-ppm) inhaled nitric oxide in patients with acute lung injury. Design and Setting Multicenter, randomized, placebo-controlled study, with blinding of patients, caregivers, data collectors, assessors of outcomes, and data analysts (triple blind), conducted in the intensive care units of 46 hospitals in the United States. Patients were enrolled between March 1996 and September 1999. Patients Patients (n = 385) with moderately severe acute lung injury, a modification of the American-European Consensus Conference definition of acute respiratory distress syndrome (ARDS) using a ratio of PaO2 to FiO2 of ≤250, were enrolled if the onset was within 72 hours of randomization, sepsis was not the cause of the lung injury, and the patient had no significant nonpulmonary organ system dysfunction at randomization. Interventions Patients were randomly assigned to placebo (nitrogen gas) or inhaled nitric oxide at 5 ppm until 28 days, discontinuation of assisted breathing, or death. Main Outcome Measures The primary end point was days alive and off assisted breathing. Secondary outcomes included mortality, days alive and meeting oxygenation criteria for extubation, and days patients were alive following a successful unassisted ventilation test. Results An intent-to-treat analysis revealed that inhaled nitric oxide at 5 ppm did not increase the number of days patients were alive and off assisted breathing (mean [SD], 10.6 [9.8] days in the placebo group and 10.7 [9.7] days in the inhaled nitric oxide group; P = .97; difference, –0.1 day [95% confidence interval, –2.0 to 1.9 days]). This lack of effect on clinical outcomes was seen despite a statistically significant increase in PaO2 that resolved by 48 hours. Mortality was similar between groups (20% placebo vs 23% nitric oxide; P =... [ABSTRACT FROM AUTHOR]

Objective: Earlier reports suggested that transthoracic (TTE) determination of the ratio of mitral inflow E wave velocity to early diastolic mitral annulus velocity (E/E') measured by tissue Doppler imaging (TDI) closely approximates PAOP in cardiac patients. However, the value of E/E' for PAOP assessment in ICU patients has not been evaluated. This study assessed whether the E/E' ratio provides an accurate estimation of pulmonary artery occlusion pressure (PAOP) in mechanically ventilated ICU patients.Design and Setting: Prospective, open, clinical study in the ICU of a university hospital.Patients: Twenty-three consecutive mechanically ventilated patients.Interventions: Volume expansion in 14 patients.Measurements and Results: Doppler TTE or TEE mitral inflow and TDI mitral annulus velocities were determined and compared with PAOP measured using a Swan-Ganz catheter. Of all the Doppler variables studied the best correlations were observed between PAOP and the lateral (r=0.84) and medial (r=0.76) annulus E/E' ratio and remained highly significant when the analysis was restricted to TEE (r=0.91 and 0.86) or TTE (r=0.73 and 0.61). The sensitivities and specificities of estimating PAOP at 15 mmHg or higher were, respectively, 86% and 81% for lateral E/E' above 7.5 and 76% and 80% for medial E/E' above 9. PAOP changes after volume expansion (700+/-230 ml) were limited and accurately assessed by repeated E/E' determinations.Conclusions: In mechanically ventilated ICU patients TTE or TEE E/E' determinations using TDI closely approximate PAOP. [ABSTRACT FROM AUTHOR]

Objective: Inhalation of perfluorocarbons (PFC) has been suggested as a new and promising technique of PFC delivery in animal models of severe lung injury. However, no in vitro data were available on the efficacy of PFC aerosolization during mechanical ventilation. Therefore, the aim of the in vitro study was to investigate the influence of physical properties of PFC and the ventilatory settings on the amount of PFC delivered into the lung.Design: In vitro lung model study.Setting: University research laboratory.Measurements and Results: Two different PFC (PF 5080 and PFOB) were aerosolized with a PariBoy jet nebulizer. Using a PFC selective adsorber, the effect of endotracheal tube size (2 mm and 3 mm diameter) on delivery of PFC was investigated. PFC delivery was estimated by continuous measurement of weight gain of the adsorber (adsorption rate). Finally, the influence of respiratory rate and tidal volume on adsorption rate (AR) was studied. AR was significantly reduced by a decreasing tube diameter and ranged from 1.45+/-0.03 ml/min (no tube) to 0.93+/-0.03 ml/min (2.0 mm) for PF 5080 (vapor pressure 51 mmHg) and from 0.49+/-0.06 ml/min to 0.32+/-0.04 ml/min for PFOB (11 mmHg). PFC-aerosolization into a ventilatory circuit with simulation of spontaneous tidal breathing (minute volume 600 ml) reduced AR to 0.16+/-0.02 ml/min. During mechanical ventilation, changes in respiratory rate and tidal volume, which reduce minute ventilation, caused a decrease in AR.Conclusion: The amount of PFC that can be delivered into the lung by aerosolization is very small and is influenced by PFC properties, tube size, and ventilatory settings. [ABSTRACT FROM AUTHOR]