Effects of starting one lung ventilation and applying individualized PEEP right after patients are placed in lateral decubitus position on intraoperative oxygenation for patients undergoing thoracoscopic pulmonary lobectomy: study protocol for a randomized controlled trial.

BACKGROUND: For patients receiving one lung ventilation in thoracic surgery, numerous studies have proved the superiority of lung protective ventilation of low tidal volume combined with recruitment maneuvers (RM) and individualized PEEP. However, RM may lead to overinflation which aggravates lung injury and intrapulmonary shunt. According to CT results, atelectasis usually forms in gravity dependent lung regions, regardless of body position. So, during anesthesia induction in supine position, atelectasis usually forms in the dorsal parts of lungs, however, when patients are turned into lateral decubitus position, collapsed lung tissue in the dorsal parts would reexpand, while atelectasis would slowly reappear in the lower flank of the lung. We hypothesize that applying sufficient PEEP without RM before the formation of atelectasis in the lower flank of the lung may beas effective to prevent atelectasis and thus improve oxygenation as applying PEEP with RM. METHODS: A total of 84 patients scheduled for elective pulmonary lobe resection necessitating one lung ventilation will be recruited and randomized totwo parallel groups. For all patients, one lung ventilation is initiated the right after patients are turned into lateral decubitus position. For patients in the study group, individualized PEEP titration is started the moment one lung ventilation is started, while patients in the control group will receive a recruitment maneuver followed by individualized PEEP titration after initiation of one lung ventilation. The primary endpoint will be oxygenation index measured at T4. Secondary endpoints will include intrapulmonary shunt, respiratory mechanics, PPCs, and hemodynamic indicators. DISCUSSION: Numerous previous studies compared the effects of individualized PEEP applied alone with that applied in combination with RM on oxygenation index, PPCs, intrapulmonary shunt and respiratory mechanics after atelectasis was formed in patients receiving one lung ventilation during thoracoscopic surgery. In this study, we will apply individualized PEEP before the formation of atelectasis while not performing RM in patients allocated to the study group, and then we're going to observe its effects on the aspects mentioned above. The results of this trial will provide a ventilation strategy that may be conductive to improving intraoperative oxygenation and avoiding the detrimental effects of RM for patients receiving one lung ventilation. TRIAL REGISTRATION: www.Chictr.org.cn ChiCTR2400080682. Registered on February 5, 2024.

Rationale and study design for an Individualized PeriopeRative Open lung VEntilatory approach in Emergency Abdominal Laparotomy/scopy: study protocol for a prospective international randomized controlled trial.

BACKGROUND: Postoperative pulmonary complications (PPC) are the most frequent postoperative complications, with an estimated prevalence in elective surgery ranging from 20% in observational cohort studies to 40% in randomized clinical trials. However, the prevalence of PPCs in patients undergoing emergency abdominal surgery is not well defined. Lung-protective ventilation aims to minimize ventilator-induced lung injury and reduce PPCs. The open lung approach (OLA), which combines recruitment manoeuvres (RM) and positive end-expiratory pressure (PEEP) titration, aims to minimize areas of atelectasis and the development of PPCs; however, there is no conclusive evidence in the literature that OLA can prevent PPCs. The purpose of this study is to compare an individualized perioperative OLA with conventional standardized lung-protective ventilation in patients undergoing emergency abdominal surgery with clinical signs of intraoperative lung collapse. METHODS: Randomized international clinical trial to compare an individualized perioperative OLA (RM plus individualized PEEP and individualized postoperative respiratory support) with conventional lung-protective ventilation (standard PEEP of 5 cmH2O and conventional postoperative oxygen therapy) in patients undergoing emergency abdominal surgery with clinical signs of lung collapse. Patients will be randomised to open-label parallel groups. The primary outcome is any severe PPC during the first 7 postoperative days, including: acute respiratory failure, pneumothorax, weaning failure, acute respiratory distress syndrome, and pulmonary infection. The estimated sample size is 732 patients (366 per group). The final sample size will be readjusted during the interim analysis. DISCUSSION: The Individualized Perioperative Open-lung Ventilatory Strategy in emergency abdominal laparotomy (iPROVE-EAL) is the first multicentre, randomized, controlled trial to investigate whether an individualized perioperative approach prevents PPCs in patients undergoing emergency surgery.

Adjunctive Therapies in Acute Respiratory Distress Syndrome.

Despite significant advances in understanding acute respiratory distress syndrome (ARDS), mortality rates remain high. The appropriate use of adjunctive therapies can improve outcomes, particularly for patients with moderate to severe hypoxia. In this review, the authors discuss the evidence basis behind prone positioning, recruitment maneuvers, neuromuscular blocking agents, corticosteroids, pulmonary vasodilators, and extracorporeal membrane oxygenation and considerations for their use in individual patients and specific clinical scenarios. Because the heterogeneity of ARDS poses challenges in finding universally effective treatments, an individualized approach and continued research efforts are crucial for optimizing the utilization of adjunctive therapies and improving patient outcomes.

Impact of Stepwise Recruitment Maneuvers on Cerebral Hemodynamics: Experimental Study in Neonatal Model.

BACKGROUND: Lung recruitment maneuvers (LRMs) have been demonstrated to be effective in avoiding atelectasis during general anesthesia in the pediatric population. Performing these maneuvers is safe at the systemic hemodynamic and respiratory levels. AIMS: We aimed to evaluate the impact of a stepwise LRM and individualized positive end-expiratory pressure (PEEP) on cerebral hemodynamics in an experimental neonatal model. METHODS: Eleven newborn pigs (less than 72 h old, 2.56 ± 0.18 kg in weight) were included in the study. The LRM was performed under pressure-controlled ventilation with a constant driving pressure (15 cmH2O) in a stepwise increasing PEEP model. The target peak inspiratory pressure (PIP) was 30 cmH2O and the PEEP was 15 cmH2O. The following hemodynamic variables were monitored using the PICCO® system: mean arterial pressure (MAP), central venous pressure (CVP), and cardiac output (CO). The cerebral hemodynamics variables monitored were intracranial pressure (ICP) (with an intraparenchymal Camino® catheter) and cerebral oxygen saturation (rSO2) (with the oximetry monitor INVOS 5100® system). The following respiratory parameters were monitored: oxygen saturation, fraction of inspired oxygen, partial pressure of oxygen, end-tidal carbon dioxide pressure, Pmean, PEEP, static compliance (Cstat), and dynamic compliance (Cdyn). RESULTS: All LRMs were safely performed as scheduled without any interruptions. Systemic hemodynamic stability was maintained during the lung recruitment maneuver. No changes in ICP occurred. We observed an improvement in rSO2 after the maneuver (+5.8%). CONCLUSIONS: Stepwise LRMs are a safe tool to avoid atelectasis. We did not observe an impairment in cerebral hemodynamics but an improvement in cerebral oxygenation.

Incidence, characteristics and risk factors for alveolar recruitment maneuver-related hypotension in patients undergoing laparoscopic colorectal cancer resection.

BACKGROUND: Alveolar recruitment maneuvers (ARMs) may lead to transient hypotension, but the clinical characteristics of this induced hypotension are poorly understood. We investigated the characteristics of ARM-related hypotension in patients who underwent laparoscopic colorectal cancer resection. AIM: To investigate the characteristics of ARM-related hypotension in patients who underwent laparoscopic colorectal cancer resection. METHODS: This was a secondary analysis of the PROtective Ventilation using Open Lung approach Or Not trial and included 140 subjects. An ARM was repeated every 30 min during intraoperative mechanical ventilation. The primary endpoint was ARM-related hypotension, defined as a mean arterial pressure (MAP) < 60 mmHg during an ARM or within 5 min after an ARM. The risk factors for hypotension were identified. The peri-ARM changes in blood pressure were analyzed for the first three ARMs (ARM1,2,3) and the last ARM (ARMlast). RESULTS: Thirty-four subjects (24.3%) developed ARM-related hypotension. Of all 1027 ARMs, 37 (3.61%) induced hypotension. More ARMs under nonpneumoperitoneum (33/349, 9.46%) than under pneumoperitoneum conditions (4/678, 0.59%) induced hypotension (P < 0.01). The incidence of hypotension was higher at ARM1 points than at non-ARM1 points (18/135, 13.3% vs 19/892, 2.1%; P < 0.01). The median percentage decrease in the MAP at ARM1 was 14%. Age ≥ 74 years, blood loss ≥ 150 mL and peak inspiratory pressure under pneumoperitoneum < 24 cm H2O were risk factors for ARM-related hypotension. CONCLUSION: When the ARM was repeated intraoperatively, a quarter of subjects developed ARM-related hypotension, but only 3.61% of ARMs induced hypotension. ARM-related hypotension most occurred in a hemodynamically unstable state or a hypovolemic state, and in elderly subjects. Fortunately, ARMs that were performed under pneumoperitoneum conditions had less impact on blood pressure.

New and personalized ventilatory strategies in patients with COVID-19.

Coronavirus disease (COVID-19) is caused by the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) virus and may lead to severe respiratory failure and the need for mechanical ventilation (MV). At hospital admission, patients can present with severe hypoxemia and dyspnea requiring increasingly aggressive MV strategies according to the clinical severity: noninvasive respiratory support (NRS), MV, and the use of rescue strategies such as extracorporeal membrane oxygenation (ECMO). Among NRS strategies, new tools have been adopted for critically ill patients, with advantages and disadvantages that need to be further elucidated. Advances in the field of lung imaging have allowed better understanding of the disease, not only the pathophysiology of COVID-19 but also the consequences of ventilatory strategies. In cases of refractory hypoxemia, the use of ECMO has been advocated and knowledge on handling and how to personalize strategies have increased during the pandemic. The aims of the present review are to: (1) discuss the evidence on different devices and strategies under NRS; (2) discuss new and personalized management under MV based on the pathophysiology of COVID-19; and (3) contextualize the use of rescue strategies such as ECMO in critically ill patients with COVID-19.

Management of refractory hypoxemia using recruitment maneuvers and rescue therapies: A comprehensive review.

Refractory hypoxemia in patients with acute respiratory distress syndrome treated with mechanical ventilation is one of the most challenging conditions in human and veterinary intensive care units. When a conventional lung protective approach fails to restore adequate oxygenation to the patient, the use of recruitment maneuvers and positive end-expiratory pressure to maximize alveolar recruitment, improve gas exchange and respiratory mechanics, while reducing the risk of ventilator-induced lung injury has been suggested in people as the open lung approach. Although the proposed physiological rationale of opening and keeping open previously collapsed or obstructed airways is sound, the technique for doing so, as well as the potential benefits regarding patient outcome are highly controversial in light of recent randomized controlled trials. Moreover, a variety of alternative therapies that provide even less robust evidence have been investigated, including prone positioning, neuromuscular blockade, inhaled pulmonary vasodilators, extracorporeal membrane oxygenation, and unconventional ventilatory modes such as airway pressure release ventilation. With the exception of prone positioning, these modalities are limited by their own balance of risks and benefits, which can be significantly influenced by the practitioner's experience. This review explores the rationale, evidence, advantages and disadvantages of each of these therapies as well as available methods to identify suitable candidates for recruitment maneuvers, with a summary on their application in veterinary medicine. Undoubtedly, the heterogeneous and evolving nature of acute respiratory distress syndrome and individual lung phenotypes call for a personalized approach using new non-invasive bedside assessment tools, such as electrical impedance tomography, lung ultrasound, and the recruitment-to-inflation ratio to assess lung recruitability. Data available in human medicine provide valuable insights that could, and should, be used to improve the management of veterinary patients with severe respiratory failure with respect to their intrinsic anatomy and physiology.

The effect of ultrasound-guided lung recruitment maneuvers on atelectasis in lung-healthy patients undergoing laparoscopic gynecologic surgery: a randomized controlled trial.

BACKGROUND: Atelectasis is the primary cause of hypoxemia during general anesthesia. This study aimed to evaluate the impact of the combination of recruitment maneuvers (RM) and positive end-expiratory pressure (PEEP) on the incidence of atelectasis in adult women undergoing gynecologic laparoscopic surgery using pulmonary ultrasound. METHODS: In this study, 42 patients with healthy lungs undergoing laparoscopic gynecologic surgery were randomly divided into the recruitment maneuver group (RM group; 6 cm H2O PEEP and RM) or the control group (C group; 6 cm H2O PEEP and no RM), 21 patients in each group. Volume-controlled ventilation was used in all selected patients, with a tidal volume of 6-8 mL·kg-1 of ideal body weight. When atelectasis was detected, patients in the RM group received ultrasound-guided RM, while those in the C group received no intervention. The incidence and severity of atelectasis were determined using lung ultrasound scores. RESULTS: A total of 41 patients were investigated. The incidence of atelectasis was lower in the RM group (40%) than in the C group (80%) 15 min after arrival in the post-anesthesia care unit (PACU). Meanwhile, lung ultrasound scores (LUSs) were lower in the RM group compared to the C group. In addition, the differences in the LUS between the two groups were mainly due to the differences in lung ultrasound scores in the posterior regions. However, this difference did not persist after 24 h of surgery. CONCLUSIONS: In conclusion, the combination of RM and PEEP could reduce the incidence of atelectasis in patients with healthy lungs 15 min after arrival at the PACU; however, it disappeared within 24 h after surgery. TRIAL REGISTRATION: (Prospectively registered): ChiCTR2000033529 . Registered on 4/6/2020.

Lung Recruitment Maneuvers Assessment by Bedside Lung Ultrasound in Pediatric Acute Respiratory Distress Syndrome.

The use of recruitment maneuvers (RMs) is suggested to improve severe oxygenation failure in patients with acute respiratory distress syndrome (ARDS). Lung ultrasound (LUS) is a non-invasive, safe, and easily repeatable tool. It could be used to monitor the lung recruitment process in real-time. This paper aims to evaluate bedside LUS for assessing PEEP-induced pulmonary reaeration during RMs in pediatric patients. A case of a child with severe ARDS due to Haemophilus influenzae infection is presented. Due to his poor clinical, laboratory, and radiological evolution, he was placed on venovenous extracorporeal membrane oxygenation (ECMO). Despite all measures, severe pulmonary collapse prevented proper improvement. Thus, RMs were indicated, and bedside LUS was successfully used for monitoring and assessing lung recruitment. The initial lung evaluation before the maneuver showed a tissue pattern characterized by a severe loss of lung aeration with dynamic air bronchograms and multiple coalescent B-lines. While raising a PEEP of 30 mmH2O, LUS showed the presence of A-lines, which was considered a predictor of reaeration in response to the recruitment maneuver. The LUS pattern could be used to assess modifications in the lung aeration, evaluate the effectiveness of RMs, and prevent lung overdistension.

The efficacy of different alveolar recruitment maneuvers in holmium laser lithotripsy surgery under general anesthesia using a laryngeal mask.

BACKGROUND: Alveolar recruitment maneuvers (ARMs) is an important part of lung-protective ventilation strategies (LPVSs), but the optimal duration and interval Remain unclear. METHODS: Patients:252 patients who underwent holmium laser lithotripsy surgery and meet inclusion criteria were included and randomized into three groups based on the duration and frequency of ARMs (Regular, one 30 s ARM (RARMs); Improved and intermittent, three 10s ARMs (IARMs); and Control (C), no ARMs). INTERVENTIONS: Groups R and I received ARMs at 20 cmH2O pressures every 30 min. All patients received the same anesthesia and mechanical ventilation. MEASUREMENTS: Outcomes included heart rate and mean arterial pressure changes during ARMs and postoperative pulmonary complications (PPCs) within the first 7 postoperative days. MAIN RESULTS: Incidences of PPCs in groups R(7.1%) and I (5.0%)were slightly lower than those in group C (8.9%).This indicated the potential to reduce lung injury. Heart rate and mean arterial pressure fluctuations during ARMs were significantly higher in groups R and I than in group C (P < 0.01). The rate of blood pressure decrease was significantly higher in group R than in group I (P < 0.01). CONCLUSIONS: IARMs can reduce cycle fluctuations than RARMs in patients Undergoing holmium laser lithotripsy surgery with laryngeal mask general anesthesia. Low tidal volume ventilation and low PEEP combined with ARM did not significantly reduce the incidence of PPCs in healthy lung patients, but tended to reduce lung injury. TRIAL REGISTRATION: The study was registered on the Chinese Clinical Trial Registry. ( ChiCTR2000030815 ,15/03/2020). This study was approved by the ethics committee of Chengdu Fifth People's Hospital with approval number(2020-005(Study)-1).

The impact of ultrasound-guided recruitment maneuvers on the risk of postoperative pulmonary complications in patients undergoing general anesthesia.

Introduction: Postoperative pulmonary complications are among the most frequent problems in perioperative care. The risk of their development depends not only on the parameters associated with the patient's initial clinical condition, but also on the employed anesthesia technique, the method of mechanical ventilation, and the type and technique of the surgical procedure. Atelectasis is the most common complication, affecting nearly 90% of the patients undergoing general anesthesia. Aim: The aim of this study was to determine whether it was possible to positively impact the postoperative period and reduce the frequency of postoperative pulmonary complications via patient-based intraoperative ultrasound-guided recruitment maneuvers. Methodology: The course of the postoperative period was analyzed in two groups of patients. One of them comprised 100 patients in whom no recruitment maneuvers were performed during general anesthesia. The other group (100 patients) consisted of patients in whom patient-based ultrasound-guided pulmonary recruitment maneuvers were performed. Results: In the recruitment group, the postoperative hospitalization was statistically significantly shorter (p = 0.003) and the risk of intensive care treatment significantly lower. Additionally, the need for prolonged postoperative mechanical ventilation was reduced, as was the risk of respiratory tract infections. Conclusions: Intraoperative ultrasound-guided recruitment maneuvers reduce the frequency of postoperative pulmonary complications.

Intraoperative open lung condition and postoperative pulmonary complications. A secondary analysis of iPROVE and iPROVE-O2 trials.

BACKGROUND: The preventive role of an intraoperative recruitment maneuver plus open lung approach (RM + OLA) ventilation on postoperative pulmonary complications (PPC) remains unclear. We aimed at investigating whether an intraoperative open lung condition reduces the risk of developing a composite of PPCs. METHODS: Post hoc analysis of two randomized controlled trials including patients undergoing abdominal surgery. Patients were classified according to the intraoperative lung condition as "open" (OL) or "non-open" (NOL) if PaO2 /FIO2 ratio was ≥ or <400 mmHg, respectively. We used a multivariable logistic regression model that included potential confounders selected with directed acyclic graphs (DAG) using Dagitty software built with variables that were considered clinically relevant based on biological mechanism or evidence from previously published data. PPCs included severe acute respiratory failure, acute respiratory distress syndrome, and pneumonia. RESULTS: A total of 1480 patients were included in the final analysis, with 718 (49%) classified as OL. The rate of severe PPCs during the first seven postoperative days was 6.0% (7.9% in the NOL and 4.4% in the OL group, p = .007). OL was independently associated with a lower risk for severe PPCs during the first 7 and 30 postoperative days [odds ratio of 0.58 (95% CI 0.34-0.99, p = .04) and 0.56 (95% CI 0.34-0.94, p = .03), respectively]. CONCLUSIONS: An intraoperative open lung condition was associated with a reduced risk of developing severe PPCs in intermediate-to-high risk patients undergoing abdominal surgery. TRIAL REGISTRATION: Registered at clinicaltrials.gov NCT02158923 (iPROVE), NCT02776046 (iPROVE-O2).

Effect of intraoperative PEEP with recruitment maneuvers on the occurrence of postoperative pulmonary complications during general anesthesia--protocol for Bayesian analysis of three randomized clinical trials of intraoperative ventilation.

Background: Using the frequentist approach, a recent meta-analysis of three randomized clinical trials in patients undergoing intraoperative ventilation during general anesthesia for major surgery failed to show the benefit of ventilation that uses high positive end-expiratory pressure with recruitment maneuvers when compared to ventilation that uses low positive end-expiratory pressure without recruitment maneuvers. Methods: We designed a protocol for a Bayesian analysis using the pooled dataset. The multilevel Bayesian logistic model will use the individual patient data. Prior distributions will be prespecified to represent a varying level of skepticism for the effect estimate. The primary endpoint will be a composite of postoperative pulmonary complications (PPC) within the first seven postoperative days, which reflects the primary endpoint of the original studies. We preset a range of practical equivalence to assess the futility of the intervention with an interval of odds ratio (OR) between 0.9 and 1.1 and assess how much of the 95% of highest density interval (HDI) falls between the region of practical equivalence. Ethics and dissemination: The used data derive from approved studies that were published in recent years. The findings of this current analysis will be reported in a new manuscript, drafted by the writing committee on behalf of the three research groups. All investigators listed in the original trials will serve as collaborative authors.

Expert opinion document: "Electrical impedance tomography: applications from the intensive care unit and beyond".

Mechanical ventilation is a life-saving technology, but it can also inadvertently induce lung injury and increase morbidity and mortality. Currently, there is no easy method of assessing the impact that ventilator settings have on the degree of lung inssflation. Computed tomography (CT), the gold standard for visually monitoring lung function, can provide detailed regional information of the lung. Unfortunately, it necessitates moving critically ill patients to a special diagnostic room and involves exposure to radiation. A technique introduced in the 1980s, electrical impedance tomography (EIT) can non-invasively provide similar monitoring of lung function. However, while CT provides information on the air content, EIT monitors ventilation-related changes of lung volume and changes of end expiratory lung volume (EELV). Over the past several decades, EIT has moved from the research lab to commercially available devices that are used at the bedside. Being complementary to well-established radiological techniques and conventional pulmonary monitoring, EIT can be used to continuously visualize the lung function at the bedside and to instantly assess the effects of therapeutic maneuvers on regional ventilation distribution. EIT provides a means of visualizing the regional distribution of ventilation and changes of lung volume. This ability is particularly useful when therapy changes are intended to achieve a more homogenous gas distribution in mechanically ventilated patients. Besides the unique information provided by EIT, its convenience and safety contribute to the increasing perception expressed by various authors that EIT has the potential to be used as a valuable tool for optimizing PEEP and other ventilator settings, either in the operative room and in the intensive care unit. The effects of various therapeutic interventions and applications on ventilation distribution have already been assessed with the help of EIT, and this document gives an overview of the literature that has been published in this context.

Mechanical Ventilation in ARDS: Quo Vadis?

Contemplating the future should be grounded in history. The rise of post-polio ICUs was inextricably related to mechanical ventilation. Critically ill patients who developed acute respiratory failure often had "congestive atelectasis" (ie, a term used to describe ARDS prior to 1967). Initial mechanical ventilation strategies for treating this condition and others inadvertently led to ventilator-induced lung injury. Both injurious ventilation and later use of overly cautious weaning practices resulted from both limited technology and understanding of ARDS and other aspects of critical illness. The resulting misperceptions, misconceptions, and missed opportunities took decades to rectify and in some instances still persist. This suggests a reluctance to acknowledge that all therapeutic strategies reflect the historical period in which they were developed and the corresponding limited understanding of ARDS pathophysiology at that time. We are at the threshold of a revolutionary moment in critical care. The confluence of enormous clinical data production, massive computing power, advances in understanding the biomolecular and genetic aspects of critical illness, and the emergence of neural networks will have enormous impact on how critical care is practiced in the decades to come. Therefore, it is imperative we understand the long-crooked path needed to reach the era of protective ventilation in order to avoid similar mistakes moving forward. The emerging era is as difficult to fathom as our current practices and technologies were to those practicing 60 years ago. This review explores the history of mechanical ventilation in treating ARDS, describes current protective ventilation strategies, and speculates how ARDS management might look 20 years from now.

Practical Review of Mechanical Ventilation in Adults and Children in the Operating Room and Emergency Department.

BACKGROUND: During general anesthesia, mechanical ventilation can cause pulmonary damage through mechanism of ventilator-induced lung injury, which is a major cause of post-operative pulmonary complications, which varies between 5 and 33% and increases the 30-day mortality of the surgical patient significantly. OBJECTIVE: The aim of this review is to analyze different variables which played a key role in the safe application of mechanical ventilation in the operating room and emergency setting. METHODS: Also, we wanted to analyze different types of the population that underwent intraoperative mechanical ventilation like obese patients, pediatric and adult population and different strategies such as one lung ventilation and ventilation in trendelemburg position. The peer-reviewed articles analyzed were selected according to PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) from Pubmed/Medline, Ovid/Wiley and Cochrane Library, combining key terms such as: "pulmonary post-operative complications", "protective ventilation", "alveolar recruitment maneuvers", "respiratory compliance", "intraoperative paediatric ventilation", "best peep", "types of ventilation". Among the 230 papers identified, 150 articles were selected, after title - abstract examination and removing the duplicates, resulting in 94 articles related to mechanical ventilation in operating room and emergency setting that were analyzed. RESULTS: Careful preoperative patient's evaluation and protective ventilation (i.e., use of low tidal volumes, adequate PEEP and alveolar recruitment maneuvers) has been shown to be effective not only in limiting alveolar de-recruitment, alveolar overdistension and lung damage, but also in reducing the onset of Pulmonary Post-operative Complications (PPCs). CONCLUSION: Mechanical ventilation is like "Janus Bi-front" because it is essential for surgical procedures, for the care of critical care patients and in life-threatening conditions, but it can be harmful to the patient if continued for a long time and where an excessive dose of oxygen is administered into the lungs. Low tidal volume is associated with a minor rate of PPCs and other complications and every complication can increase the length of Stay, adding cost to NHS between 1580 € and 1650 € per day in Europe and currently the prevention of PPCS is the only weapon that we possess.

Lung ultrasound guided pulmonary recruitment during mechanical ventilation in neonates: A case series.

BACKGROUND: Recently, the first report of lung ultrasound (LUS) guided recruitment during open lung ventilation in neonates has been published. LUS guided recruitment can change the approach to open lung ventilation, which is currently performed without any measure of lung function/lung expansion in the neonatal population. METHODS: We included all the newborn infants that underwent a LUS-guided recruitment maneuver during mechanical ventilation as a rescue attempt for an extremely severe respiratory condition with oxygen saturation/fraction of inspired oxygen (SpO2/FIO2) ratio below 130 or the inability to wean off mechanical ventilation. RESULTS: We report a case series describing 4 LUS guided recruitment maneuvers, underlying crucial aspects of this technique that can improve the effectiveness of the procedure. In particular, we describe a novel pattern (the S-pattern) that allows us to distinguish the recruitable from the unrecruitable lung and guide the pressure titration phase. Additionally, we describe the optimal LUS-guided patient positioning. CONCLUSIONS: We believe that the inclusion of specifications regarding patient positioning and the S-pattern in the LUS-guided protocol may be beneficial for the success of the procedure.

Certified Registered Nurse Anesthetists' Adherence to an Intraoperative Lung Protective Ventilation Protocol.

The clinical application of intraoperative mechanical ventilation is highly variable and often determined by providers' attitudes and preferences, rather than evidence. Ventilation strategies using high tidal volumes (VT) with little to no positive end-expiratory pressure (PEEP) are associated with lung injury, increasing the risk of postoperative pulmonary complications. Literature demonstrates that applying lung protective ventilation (LPV) strategies intraoperatively, including low VT, individualized PEEP, and alveolar recruitment maneuvers, can reduce the risk of postoperative pulmonary complications. This multicenter quality improvement project aimed to develop and implement an LPV protocol to increase nurse anesthetists' knowledge and adherence to LPV strategies in adults undergoing laparoscopic cholecystectomy. The anesthesia providers were educated about LPV strategies and their intraoperative application to individualize ventilation settings based on patient comorbidities and body habitus. Adherence was determined by collecting ventilator data and evaluating the data using logistic regression. The overall protocol adherence significantly increased (P=.01). Additionally, there was a significant improvement in adherence to each individual component of the protocol (all P<.05) except for VT. Decreasing the oxygen concentration administered during maintenance and emergence was the most commonly adopted practice (P<.0001). This project demonstrates that education and a standardized protocol can increase the use of intraoperative LPV strategies.

Assessment of the Effect of Recruitment Maneuver on Lung Aeration Through Imaging Analysis in Invasively Ventilated Patients: A Systematic Review.

Background: Recruitment maneuvers (RMs) have heterogeneous effects on lung aeration and have adverse side effects. We aimed to identify morphological, anatomical, and functional imaging characteristics that might be used to predict the RMs on lung aeration in invasively ventilated patients. Methods: We performed a systemic review. Studies included invasively ventilated patients who received an RM and in whom re-aeration was examined with chest computed tomography (CT), electrical impedance tomography (EIT), and lung ultrasound (LUS) were included. Results: Twenty studies were identified. Different types of RMs were applied. The amount of re-aerated lung tissue after an RM was highly variable between patients in all studies, irrespective of the used imaging technique and the type of patients (ARDS or non-ARDS). Imaging findings suggesting a non-focal morphology (i.e., radiologic findings consistent with attenuations with diffuse or patchy loss of aeration) were associated with higher likelihood of recruitment and lower chance of overdistention than a focal morphology (i.e., radiological findings suggestive of lobar or segmental loss of aeration). This was independent of the used imaging technique but only observed in patients with ARDS. In patients without ARDS, the results were inconclusive. Conclusions: ARDS patients with imaging findings suggestive of non-focal morphology show most re-aeration of previously consolidated lung tissue after RMs. The role of imaging techniques in predicting the effect of RMs on re-aeration in patients without ARDS remains uncertain.