Atelectasis In Patients Research Articles

Impact of Manual Sustained Inflation vs Stepwise PEEP on Pulmonary and Cerebral Outcomes in Carotid Endarterectomy Patients.

BACKGROUND Recruitment maneuvers (RMs) are used to reduce pulmonary atelectasis in patients under general anesthesia, but they can lead to a decrease in cerebral hemodynamics. MATERIAL AND METHODS Thirty patients undergoing carotid endarterectomy were randomized to a manual sustained inflation (SI) group or a stepwise increase in PEEP (IP) group. During both RMs, the peak airway pressure (Ppeak) was maintained at 30 cmH₂O for 30 s. Electrical impedance tomography was used to evaluate pulmonary aeration changes. Mean velocity of blood flow in the middle cerebral artery (Vm) and cerebral oxygen saturation (rScO₂) was monitored intraoperatively. RESULTS IP improved lung aeration better at Ppeak=30 cmH₂O than SI (58.2±8.4% vs 46.0±8.3%, P=0.001) and this persisted until the end of surgery. Dorsal (dependent) ventilation 30 min after extubation in the SI group was lower than that before surgery (7.7±2.6% vs 9.9±3.8%, P=0.003). Vm and rScO₂ returned to baseline immediately after RM in the SI group, while it remained below baseline in the IP group (42.5±12.6 vs 50.9±18.8 cm/s, P<0.001 and 68.1±3.5% vs 70.6±3.7%, P=0.001). Heart rate declined significantly during RM only in the SI group (55.9±6.6 vs 52.2±6.9 bpm, P=0.008). CONCLUSIONS Compared with SI, IP performed better in improving lung aeration, with greater hemodynamic stability. IP resulted in slower recovery of cerebral blood flow and oxygenation.

Preoperative Atelectasis in Patients with Obesity Undergoing Bariatric Surgery: A Cross-Sectional Study.

Pulmonary atelectasis is present even before surgery in patients with obesity. We aimed to estimate the prevalence and extension of preoperative atelectasis in patients with obesity undergoing bariatric surgery and to determine if variation in preoperative Spo2 values in the seated position at room air is explained by the extent of atelectasis coverage in the supine position. This was a cross-sectional study in a single center specialized in laparoscopic bariatric surgery. Preoperative chest computed tomographies were reassessed by a senior radiologist to quantify the extent of atelectasis coverage as a percentage of total lung volume. Patients were classified as having atelectasis when the affection was ≥2.5%, to estimate the prevalence of atelectasis. Crude and adjusted prevalence ratios (aPRs) and odds ratios (aORs) were obtained to assess the relative prevalence of atelectasis and percentage coverage, respectively, with increasing obesity category. Inverse probability weighting was used to assess the total, direct (not mediated), and indirect (mediated through atelectasis) effects of body mass index (BMI) on preoperative Spo2, and to quantify the magnitude of mediation (proportion mediated). E-values were calculated, to represent the minimum magnitude of association that an unmeasured confounder with the same directionality of the effect should have to drive the observed point estimates or lower confidence intervals (CIs) to 1, respectively. In 236 patients with a median BMI of 40.3 kg/m2 (interquartile range [IQR], 34.6-46.0, range: 30.0-77.3), the overall prevalence of atelectasis was 32.6% (95% CI, 27.0-38.9) and by BMI category: 30 to 35 kg/m2, 12.7% (95% CI, 6.1-24.4); 35 to 40 kg/m2, 28.3% (95% CI, 17.2-42.6); 40 to 45 kg/m2, 12.3% (95% CI, 5.5-24.3); 45 to 50 kg/m2, 48.4% (95% CI, 30.6-66.6); and ≥50 units, 100% (95% CI, 86.7-100). Compared to the 30 to 35 kg/m2 group, only the categories with BMI ≥45 kg/m2 had significantly higher relative prevalence of atelectasis-45 to 50 kg/m2, aPR = 3.52 (95% CI, 1.63-7.61, E-value lower bound: 2.64) and ≥50 kg/m2, aPR = 8.0 (95% CI, 4.22-15.2, E-value lower bound: 7.91)-and higher odds of greater atelectasis percentage coverage: 45-50 kg/m2, aOR = 7.5 (95% CI, 2.7-20.9) and ≥50 kg/m2, aOR = 91.5 (95% CI, 30.0-279.3). Atelectasis percent alone explained 70.2% of the variation in preoperative Spo2. The proportion of the effect of BMI on preoperative Spo2 values <96% mediated through atelectasis was 81.5% (95% CI, 56.0-100). The prevalence and extension of atelectasis increased with higher BMI, being significantly higher at BMI ≥45 kg/m2. Preoperative atelectasis mediated the effect of BMI on Spo2 at room air in the seated position.

Effects of small-dose S-ketamine on anesthesia-induced atelectasis in patients undergoing general anesthesia accessed by lung ultrasound: study protocol for a randomized, double-blinded controlled trial.

Atelectasis after anesthesia induction in most patients undergoing general anesthesia may lead to postoperative pulmonary complications (PPCs) and affect postoperative outcomes. However, there is still no existing effective method used for the prevention of perioperative atelectasis. S-ketamine may prevent atelectasis due to airway smooth muscle relaxation and anti-inflammatory effects. Lung ultrasound is a portable and reliable bedside imaging technology for diagnosing anesthesia-induced atelectasis. The primary objective of this study is to assess whether a small dose of S-ketamine can reduce the incidence of atelectasis after intubation, and further investigate the effects of preventing the early formation of perioperative atelectasis and PPCs. This is a single-institution, prospective, randomized controlled, parallel grouping, and double-blind study. From October 2020 to March 2022, 100 patients (18-60 years old) scheduled for elective surgery will be recruited from Beijing Tiantan Hospital, Capital Medical University, and randomly assigned to the S-ketamine group (group 1) and the normal saline group (group 2) at a ratio of 1:1. The label-masked agents will be administered 5 min before induction, and all patients will undergo a standardized general anesthesia protocol. Related data will be collected at three time points: after radial artery puncture (T1), 15 min after tracheal intubation (T2), and before extubation (T3). The primary outcome will be the total lung ultrasound scores (LUS) at T2. Secondary outcomes will include LUS in six chest regions at T2, total LUS at T3, arterial blood gas analysis results (PaCO2, PaO2) and PaO2/FiO2 at T2 and T3, and plateau pressure (Pplat) and dynamic lung compliance (Cdyn) at T2 and T3. The incidence of postoperative complications associated with S-ketamine and PPCs at 2 h and 24 h after surgery will be recorded. This trial aims to explore whether a simple and feasible application of S-ketamine before the induction of general anesthesia can prevent atelectasis. The results of this study may provide new ideas and direct clinical evidence for the prevention and treatment of perioperative pulmonary complications during anesthesia. ClinicalTrials.gov NCT04745286. Registered onFebruary 9, 2021.

Predictive value of gradient boosting decision trees for postoperative atelectasis complications in patients with pulmonary destruction.

To explore the application value of a gradient boosting decision tree (GBDT) in predicting postoperative atelectasis in patients with destroyed lungs. A total of 170 patients with damaged lungs who underwent surgical treatment in Chest Hospital of Guangxi Zhuang Autonomous Region from January 2021 to May 2023 were retrospectively selected. The patients were divided into a training set (n = 119) and a validation set (n = 51). Both GBDT algorithm model and Logistic regression model for predicting postoperative atelectasis in patients were constructed. The receiver operating characteristic (ROC) curve, calibration curve and decision curve were used to evaluate the prediction efficiency of the model. The GBDT model indicated that the relative importance scores of the four influencing factors were operation time (51.037), intraoperative blood loss (38.657), presence of lung function (9.126) and sputum obstruction (1.180). Multivariate Logistic regression analysis revealed that operation duration and sputum obstruction were significant predictors of postoperative atelectasis among patients with destroyed lungs within the training set (P = 0.048, P = 0.002). The ROC curve analysis showed that the area under the curve (AUC) for GBDT and Logistic model in the training set was 0.795 and 0.763, and their AUCs in the validation set were 0.776 and 0.811. The GBDT model's predictions closely matched the ideal curve, showing a higher net benefit than the reference line. GBDT model is suitable for predicting the incidence of complications in small samples.

Comparative analysis of pulmonary ventilation distribution between low-cost and branded incentive spirometers using electrical impedance tomography in healthy adults: Study protocol.

The Incentive Spirometer (IS) increases lung volume and improves gas exchange by visually stimulating patients to take slow, deep breaths. It prevents respiratory complications and treats postoperative atelectasis in patients undergoing abdominal, thoracic, and neurosurgical procedures. Its effectiveness has been validated in studies that support improved lung capacities and volumes in individuals with respiratory complications, postoperative thoracic surgery, upper abdominal surgery, and bariatric surgery. The modified Pachón incentive spirometer (MPIS) is a cost-effective alternative to branded IS. It is crucial to validate whether the MPIS distributes ventilation as effectively as commercial devices do. Ventilation distribution will be measured using electrical impedance tomography. The aim is to compare the distribution of pulmonary ventilation between the MPIS and another commercial IS in healthy adults using electrical impedance tomography. A crossover clinical trial is proposed to evaluate the measurement of pulmonary ventilation distribution using EIT in a sample of healthy adults. All participants will use a commercial flow IS and the MPIS, with the order of assignment randomized. This research will use electrical impedance tomography to validate the operation of the MPIS. This study protocol will compare two incentive spirometers' impact on pulmonary ventilation, potentially endorsing the adoption of a cost-effective device to enhance accessibility for targeted populations. The study was registered in ClinicalTrials.gov (NTC05532748).

Effect of high-frequency oscillation on reduction of atelectasis in perioperative patients: a prospective randomized controlled study

Background Atelectasis affects approximately 90% of anaesthetized patients, with laparoscopic surgery and pneumoperitoneum reported to exacerbate this condition. High-frequency oscillation therapy applies continuous positive pressure pulses to oscillate the airway, creating a pressure difference in small airways obstructed by secretions. This process helps reduce peak airway pressure, open small airways, and decrease atelectasis incidence, while also facilitating respiratory tract clearance. This study examines the efficacy of high-frequency oscillation on reduction of atelectasis in laparoscopic cholecystectomy (LC) patients under general anaesthesia, evaluated using lung ultrasound. Methods Sixty-four patients undergoing laparoscopic cholecystectomy were randomly divided into a control group and a high-frequency oscillation (HFO) group. Both groups underwent total intravenous anaesthesia under invasive arterial monitoring. The HFO group received a 10-minute continuous high-frequency oscillation therapy during surgery, while the control group received no intervention. Lung ultrasound evaluations were performed three times: five minutes post-intubation (T1), at the end of the surgery (T2), and before leaving the Post-Anaesthesia Care Unit (PACU; T3). Blood gas analysis was performed twice: prior to induction with no oxygen supply and before PACU discharge (oxygen supply off). Results The HFO group displayed a significantly lower incidence of atelectasis at T3 (57.5% vs. 90.3%, OR 6.88, 95%CI (1.74 to 27.24)) compared to the control group. Moreover, the HFO group’s PaO2 levels remained consistent with baseline levels before PACU discharge, unlike the control group. Although there was no significant difference in LUS scores between the groups at T1 (8.56 ± 0.15 vs. 8.19 ± 0.18, p = 0.1090), the HFO group had considerably lower scores at T2 (13.41 ± 0.17 vs.7.59 ± 0.17, p < 0.01) and T3 (13.72 ± 0.14 vs.7.25 ± 0.21, p < 0.01). Conclusion Our study indicates that high-frequency oscillation effectively reduces atelectasis in patients undergoing laparoscopic cholecystectomy. Additionally, it can mitigate the decline in oxygen partial pressure associated with atelectasis.

Early Postoperative Fever and Atelectasis in Patients Undergoing Upper Abdominal Surgery.

Atelectasis is a common complication after upper abdominal surgery and considered as a cause of early postoperative fever (EPF) within 48 hours after surgery. However, the pathophysiologic mechanism of how atelectasis causes fever remains unclear. Data for adult patients who underwent elective major upper abdominal surgery under general anesthesia at Seoul National University Hospital between January and December of 2021 were retrospectively analyzed. The primary outcome was the association between fever and atelectasis within 2 days after surgery. Of 1,624 patients, 810 patients (49.9%) developed EPF. The incidence of atelectasis was similar between the fever group and the no-fever group (51.6% vs 53.9%, p = 0.348). Multivariate analysis showed no significant association between atelectasis and EPF. Culture tests (21.7% vs 8.8%, p < 0.001) and prolonged use of antibiotics (25.9% vs 13.9%, p < 0.001) were more frequent in the fever group compared to the no-fever group. However, the frequency of bacterial growth on culture tests and postoperative pulmonary complications within 7 days were similar between the two groups. EPF after major upper abdominal surgery was not associated with radiologically detected atelectasis. EPF also was not associated with the increased risk of postoperative pulmonary complications, bacterial growth on culture studies, or prolonged length of hospital stay.

Comparison of the Effect of Inhalation and Intermittent Inhalation-Exhalation Incentive Spirometry on Dyspnea Severity and Atelectasis in Patients undergoing Coronary Artery Bypass Graft

Background: Dyspnea and atelectasis after Coronary Artery Bypass Graft (CABG) are common and need nursing attention. Inhalation and exhalation incentive spirometry is recommended for preventing alveolar collapse and atelectasis. Objectives: This study aimed to compare different methods of incentive spirometry on dyspnea severity and atelectasis of the patients undergoing CABG. Methods: This randomized clinical trial study was conducted on 66 patients undergoing CABG admitted to the Intensive Care Unit (ICU) of Cardiac Surgery Department in Hamadan, Iran, in 2020. The patients were selected through convenient sampling and were divided into two groups through block permutation: inhalation incentive spirometry and intermittent inhalation-exhalation spirometry. Both groups performed incentive spirometry according to the instructions they had received for four days. Then, they were examined for dyspnea and atelectasis using the Borg scale and chest x-ray, respectively. Results: During the intervention, dyspnea significantly decreased in the intermittent inhalation-exhalation group relative to the inhalation group (P&lt;0.05). Most patients in both inhalation (63.6%) and intermittent inhalation-exhalation (65.6%) groups had atelectasis; however, no significant differences were observed between the two groups (P=0.867). Conclusion: Incentive spirometry via intermittent inhalation-exhalation method was more effective on dyspnea compared to the inhalation method. Therefore, this method is recommended to patients and nurses to reduce pulmonary complications after CABG

Positive end-expiratory pressure and postoperative complications in patients with obesity: a review and meta-analysis.

In patients with obesity, use of positive end-expiratory pressure (PEEP) > 5 cm H2 O (centimeters of water) has been shown to prevent intraoperative atelectasis. This study compares the rate of postoperative pulmonary complications (PPCs) associated with PEEP > 5 cm H2 O and PEEP ≤ 5 cm H2 O in patients with obesity who underwent surgery under general anesthesia with mechanical ventilation. This study searched Medline, Embase, the Cochrane Central Register of Controlled Trials (CENTRAL), and the Cumulative Index to Nursing and Allied Health Literature (CINAHL) using the terms "PEEP," "anesthesia," and "ventilation." Cochrane ReviewManager (RevMan) version 5 was used for data analysis. The primary outcome was a composite of PPCs, including atelectasis, pneumonia, pneumothorax, and acute respiratory failure. The initial search identified 903 titles and abstracts, and 4 randomized controlled trials were included for analysis. We included a total of 2116 participants from four randomized controlled trials that compared PEEP ≤ 5 cm H2 O with PEEP > 5 cm H2 O in adult patients with obesity. There was no statistically significant difference in PPCs between the PEEP ≤ 5 cm H2 O and PEEP > 5 cm H2 O groups (risk ratio=2.21, 95% CI: 0.41-11.83; p=0.35). However, a significant heterogeneity was found within included studies (I2 = 53%). It is unclear whether PEEP > 5 cm H2 O improves the postoperative clinical outcome in patients with obesity, which is in contrast to previously established evidence that it reduces atelectasis in patients with obesity.

Tuberculosis with isolated atelectasis: a case report

Introduction Tuberculosis is a significant health issue in developing countries, with the World Health Organization reporting over 10 million cases worldwide in 2014. While methods exist for rapid investigation of Mycobacterium tuberculosis, radiological imaging may lead to an earlier suspicion, such as presence of cavitation. In this case report, a patient with only radiological finding being atelectasis will be presented. Case Presentation An 18 years old female patient with no specific medical background history had been evaluated at an outpatient clinic with complaints of cough and exertional dyspnea. After a fluoroquinolone treatment for 7 days given for a pericardiac density in chest radiography, patient was admitted due to limited clinical response. A chest tomography was performed while the patient was under wide spectrum antibiotics and atelectasis in right lower lobe was observed. Repeated Acid-Fast Bacilli smears and sputum samples were found negative and bronchoscopy sampling did not show any findings of obstruction. Mycobacterium tuberculosis complex DNA was later detected in the lavage samples for which antituberculosis treatment was initiated with a regimen of isoniazid 5 mg/kg, pyrazinamide 25 mg/kg, ethambutol 15 mg/kg, and rifampin 10mg/kg. Discussion The diagnosis of tuberculosis, in this case, was probably masked during the AFB smear testing due to a treatment regimen of fluoroquinolone. The general radiological definition of tuberculosis primarily consists of older studies, with the expected presentation being a combination of cavitation and infiltration. Normal lung imaging results had also been described for tuberculosis regarding chest radiography, and studies have reported the presence of atelectasis in patients with tuberculosis, as seen in tomography case series; however, the isolation of atelectasis had not been specified in the studies. Conclusion Pulmonary tuberculosis may present itself with a myriad of radiological findings. This presentation often complicates the diagnostic process; however, differential diagnosis can be achieved via a combination of clinical symptoms and rapid culture sampling.

In 18F-positron emission tomography/computed tomography-guided precision radiotherapy for centrally located non-small cell lung cancer, tumor related atelectasis is a prognostic factor of survival.

PurposeTumor related atelectasis(TRA) is an essential factor affecting survival that can cause chest pain, cough, hemoptysis, chest tightness, dyspnea, and even death. In the current study, we explored the possible impact of TRA on survival in cancer patients and the guiding significance of 18F-positron emission tomography/computed(PET/CT) in radiotherapy for patients with atelectasis tumors.MethodsIn this retrospective study, we analyzed the treatment model and survival of patients with centrally located non-small cell lung cancer(NSCLC) treated with radiotherapy at two medical centers between May 2005 and August 2019. We identified 152 eligible patients and used propensity score matching (1:1) to process the data to reduce confounding factors, data bias, and mal-distribution.ResultsWe used propensity scores created well-matched groups of 57 patients overall with or without TRA. The one-year survival rate of all patients was 71.9%, and the two-year survival rate was 33.3%. Compared to the atelectasis group, the overall survival (OS) of patients in the non-atelectasis group was significantly prolonged (25 months vs. 17 months, p = 0.004), as well as in the atelectasis recovery group (28 months vs. 14 months, p = 0.008). In multivariate analysis, non-atelectasis was closely correlated with favorable OS (HR, 1.804 (−2.840); 95% CI, 1.145–2.840; p = 0.011).ConclusionPET/CT can accurately stage NSCLC and better guide the treatment of NSCLC complicated with atelectasis. Tumor-associated atelectasis in patients with centrally located NSCLC can lead to is a poor prognostic marker.

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

BackgroundAtelectasis 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.MethodsIn 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.ResultsA 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.ConclusionsIn 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.

Extended Lung Ultrasound to Differentiate Between Pneumonia and Atelectasis in Critically Ill Patients: A Diagnostic Accuracy Study.

To determine the diagnostic accuracy of extended lung ultrasonographic assessment, including evaluation of dynamic air bronchograms and color Doppler imaging to differentiate pneumonia and atelectasis in patients with consolidation on chest radiograph. Compare this approach to the Simplified Clinical Pulmonary Infection Score, Lung Ultrasound Clinical Pulmonary Infection Score, and the Bedside Lung Ultrasound in Emergency protocol. Prospective diagnostic accuracy study. Adult ICU applying selective digestive decontamination. Adult patients that underwent a chest radiograph for any indication at any time during admission. Patients with acute respiratory distress syndrome, coronavirus disease 2019, severe thoracic trauma, and infectious isolation measures were excluded. None. Lung ultrasound was performed within 24 hours of chest radiograph. Consolidated tissue was assessed for presence of dynamic air bronchograms and with color Doppler imaging for presence of flow. Clinical data were recorded after ultrasonographic assessment. The primary outcome was diagnostic accuracy of dynamic air bronchogram and color Doppler imaging alone and within a decision tree to differentiate pneumonia from atelectasis. Of 120 patients included, 51 (42.5%) were diagnosed with pneumonia. The dynamic air bronchogram had a 45% (95% CI, 31-60%) sensitivity and 99% (95% CI, 92-100%) specificity. Color Doppler imaging had a 90% (95% CI, 79-97%) sensitivity and 68% (95% CI, 56-79%) specificity. The combined decision tree had an 86% (95% CI, 74-94%) sensitivity and an 86% (95% CI, 75-93%) specificity. The Bedside Lung Ultrasound in Emergency protocol had a 100% (95% CI, 93-100%) sensitivity and 0% (95% CI, 0-5%) specificity, while the Simplified Clinical Pulmonary Infection Score and Lung Ultrasound Clinical Pulmonary Infection Score had a 41% (95% CI, 28-56%) sensitivity, 84% (95% CI, 73-92%) specificity and 68% (95% CI, 54-81%) sensitivity, 81% (95% CI, 70-90%) specificity, respectively. In critically ill patients with pulmonary consolidation on chest radiograph, an extended lung ultrasound protocol is an accurate and directly bedside available tool to differentiate pneumonia from atelectasis. It outperforms standard lung ultrasound and clinical scores.

Persistent Pulmonary Atelectasis in Patient with Rheumatoid Arthritis Treated with High-Flow Therapy and High-Frequency Chest Wall Oscillation

Rheumatoid arthritis is a systemic inflammatory disorder that affects ∼1-2% of the population. Although a progressive destruction of cartilage and bone is the main presentation, extra-articular manifestations can occur in about 40% of patients during the course of their disease and are associated with significant morbidity and increased mortality. Pulmonary complications can frequently occur in these patients, although not always clinically recognized. We present a case of 60-year-old woman suffering from rheumatoid arthritis came to our department for the presence of exertional dyspnea, cough with poor mucous expectoration, chest pain and worsening of daytime asthenia. At a chest x-ray, evidence of right basal pulmonary atelectasis, for which she had practiced antibiotic therapy with persistence of symptomatology and pulmonary atelectasis. Chest CT showed parenchymal consolidation. The patient was treated with antibiotics and rehabilitation therapy, bronchial endoscopy, with persistence of pulmonary atelectasis. She started nasal high-flow therapy but in the seventh day appears epistaxis. For this reason, she suspended treatment with NHF. At the next rehabilitation session, for the recurrence of epistaxis, an otorhinolaryngology visit was performed that confirms the presence of nasal varices. Therefore, the patient started high-flow therapy with a mouthpiece with the use of High Frequency Chest Wall Oscillation. At the end of rehabilitative treatment we observed clinical and radiological improvement.

Recruitment maneuvers in patients undergoing thoracic surgery: a meta-analysis.

Pulmonary atelectasis is a common postoperative complication that may lead to intrapulmonary shunt, refractory hypoxemia, and respiratory distress. Recruitment maneuvers may relieve pulmonary atelectasis in patients undergoing thoracic surgery. This meta-analysis of randomized controlled trials (RCTs) is to evaluate the effectiveness and safety of recruitment maneuvers in patients undergoing thoracic surgery. We performed a literature search on the PubMed, Embase, and Cochrane Library databases and the ClinicalTrials.gov registry for trials published before April 2021. We investigated postoperative pulmonary atelectasis incidence, intrapulmonary shunt fraction, static lung compliance, and mean arterial pressure. Six RCTs involving 526 patients were reviewed. Patients receiving a recruitment maneuver exhibited a significant decrease in intrapulmonary shunt fraction [weighted mean difference (WMD) - 0.02, 95% CI - 0.03 to - 0.01], improved static lung compliance (WMD 2.16; 95% CI 1.14-3.18), and PaO2/FIO2 ratio (WMD 31.31; 95% CI 12.11-50.52) without a significant difference in mean arterial pressure (WMD - 0.64; 95% CI - 4.92 to 3.64). The incidence pulmonary atelectasis favored recruitment maneuver group, but was not statistically significant (RR 0.55; 95% CI 0.27-1.12). Recruitment maneuvers may be a viable treatment for reducing intra-pulmonary shunt and improving static lung compliance and PaO2/FIO2 ratio without the disturbance of hemodynamics in patients undergoing thoracic surgery.

Analysis of the influencing factors and nursing strategy for acute atelectasis after traumatic brain injury surgery.

Acute atelectasis is common after traumatic brain injury (TBI), but the related factors and treatment are still unclear. This study is to analyze the independent risk factors for acute atelectasis after TBI and propose an interventional nursing strategy, in order to correct respiratory function and improve the prognosis of patients. The clinical data of 93 patients with TBI admitted to our hospital from April 2015 to October 2019 were retrospectively analyzed. Clinical data were analyzed by single factor analysis, the cutoff value of influencing factors was obtained by receiver operating characteristic (ROC) curve analysis, and the influencing factors for acute atelectasis after TBI were examined by multi-factor logistic regression. Twenty-two patients (23.66%) were complicated with acute atelectasis during the observation period, while the remaining 71 patients (76.34%) did not have acute atelectasis. Univariate analysis showed that there were significant differences in the Glasgow Coma Scale (GCS), history of vomiting and aspiration, mannitol use, mechanical ventilation, hypoalbuminemia, and serum hypoxia-inducible factor-1α (HIF-1α) between the acute atelectasis group and the non-acute atelectasis group (P<0.05). The AUC area of HIF-1α level predicting acute atelectasis was 0.896 [95% confidence interval (CI): 0.814-0.978, P=0.042], and the cut-off value was 2.12 mmol/L, with a sensitivity of 76.9% and a specificity of 93.3%. Logistic regression analysis showed that a history of vomiting and aspiration [odds ratio (OR) 3.908, 95% confidence interval (CI): 1.201-12.712], mechanical ventilation (OR 3.250, 95% CI: 1.139-9.271), hypoalbuminemia (OR 5.741, 95% Cl: 1.926-17.113), and HIF-1α ≥2.12 mmol/L (OR 6.623, 95% CI: 2.364-16.346) were independent risk factors for acute atelectasis after TBI. A history of vomiting and aspiration, mechanical ventilation, hypoalbuminemia, and high expression of HIF-1α are all independent risk factors for postoperative acute atelectasis in patients with TBI. In clinical practice, patients should be guided to swallow properly, breathe smoothly, eat well, and regularly check the relevant indexes.

Perioperative high inspired oxygen fraction induces atelectasis in patients undergoing abdominal surgery: A randomized controlled trial

Study objectiveWe evaluated the feasibility of use and effects on postoperative atelectasis and complications of lower inspired oxygen fraction (FIO2) compared to conventional oxygen therapy. DesignSingle center, randomized clinical trial. SettingUniversity hospital, operating room and postoperative recovery area. PatientsOne hundred ninety patients aged ≥50 with an American Society of Anesthesiologists physical status of I-III who underwent abdominal surgery with general anesthesia. InterventionsParticipants were randomly assigned to either the low FIO2 group (intraoperative: FIO2 0.35, during induction and recovery: FIO2 0.7) or the conventional FIO2 group (intraoperative: FIO2 0.6, during induction and recovery: FIO2 1.0). MeasurementsThe primary outcome was postoperative atelectasis measured with lung ultrasonography at postoperative 30 min in the post-anesthesia care unit (consolidation score: each region 0–3, 12 region, total score range of 0 to 36, a lower score indicating better aeration). Main resultsSeven patients in the low FIO2 group were omitted from the study due to changing FIO2 during intervention (7/95 (8.4%) vs. 2/95 (2.1%), p = 0.088; low FIO2 group vs. conventional FIO2 group). Overall, atelectasis was detected in 29.7% (51/172) of patients 30 min after surgery by lung ultrasound and 40.1% (69/172) of patients after 2 days after surgery by chest X-ray. The scores of lung ultrasonography and the incidence of significant atelectasis (consolidation score ≥ 2 at any region) were lower in the low FIO2 group than in the conventional FIO2 group (median [IQR]: 3 [1,6] vs. 7 [3,9], p < 0.001 and 17/85 (20%) vs. 34/87 (39%), RR: 0.512 [95% CI: 0.311–0.843], p = 0.006, respectively). The incidence of surgical site infection and length of hospitalization were not significantly different between the two groups. ConclusionsBased on our findings, decreased inspired oxygen fraction during anesthesia and recovery did not cause hypoxic events, but instead reduced immediate postoperative atelectasis. The use of intraoperative conventional higher inspired oxygen did not afford any clinical advantages for postoperative recovery in abdominal surgery.

The Effect of Ventilation with Individualized Positive End-Expiratory Pressure on Postoperative Atelectasis in Patients Undergoing Robot-Assisted Radical Prostatectomy: A Randomized Controlled Trial.

For patients undergoing robot-assisted radical prostatectomy, the pneumoperitoneum with a steep Trendelenburg position could worsen intraoperative respiratory mechanics and result in postoperative atelectasis. We investigated the effects of individualized positive end-expiratory pressure (PEEP) on postoperative atelectasis, evaluated using lung ultrasonography. Sixty patients undergoing robot-assisted radical prostatectomy were randomly allocated into two groups. Individualized groups (n = 30) received individualized PEEP determined by a decremental PEEP trial using 20 to 7 cm H2O, aiming at maximizing respiratory compliance, whereas standardized groups (n = 30) received a standardized PEEP of 7 cm H2O during the pneumoperitoneum. Ultrasound examination was performed on 12 sections of thorax, and the lung ultrasound score was measured as 0–3 by considering the number of B lines and the degree of subpleural consolidation. The primary outcome was the difference between the lung ultrasound scores measured before anesthesia induction and just after extubation in the operating room. An increase in the difference means the development of atelectasis. The optimal PEEP in the individualized group was determined as the median (interquartile range) 14 (12–18) cm H2O. Compared with the standardized group, the difference in the lung ultrasound scores was significantly smaller in the individualized group (−0.5 ± 2.7 vs. 6.0 ± 2.9, mean difference −6.53, 95% confidence interval (−8.00 to −5.07), p < 0.001), which means that individualized PEEP was effective to reduce atelectasis. The lung ultrasound score measured after surgery was significantly lower in the individualized group than the standardized group (8.1 ± 5.7 vs. 12.2 ± 4.2, mean difference −4.13, 95% confidence interval (−6.74 to −1.53), p = 0.002). However, the arterial partial pressure of the oxygen/fraction of inspired oxygen levels during the surgery showed no significant time-group interaction between the two groups in repeated-measures analysis of variance (p = 0.145). The incidence of a composite of postoperative respiratory complications was comparable between the two groups. Individualized PEEP determined by maximal respiratory compliance during the pneumoperitoneum and steep Trendelenburg position significantly reduced postoperative atelectasis, as evaluated using lung ultrasonography. However, the clinical significance of this finding should be evaluated by a larger clinical trial.

Recruitment maneuvers to reduce pulmonary atelectasis after cardiac surgery: A meta-analysis of randomized trials.

Pulmonary atelectasis is a common postoperative complication that may lead to intrapulmonary shunt, refractory hypoxemia, and respiratory distress. Recruitment maneuvers may relieve pulmonary atelectasis in patients undergoing cardiac surgery. We conducted a meta-analysis of randomized controlled trials to evaluate the effectiveness of recruitment maneuvers in these patients. We conducted a search in PubMed, Embase, Cochrane Library, and the ClinicalTrials.gov registry for trials published before March 2020. Individual effect sizes were standardized, and a meta-analysis was performed to calculate a pooled effect size by using random-effects models. Pulmonary atelectasis was assessed postoperatively. Secondary outcomes included hypoxic events, arterial oxygen tension (Pao2)/inspired oxygen fraction (Fio2) ratio, cardiac index, mean arterial pressure, and postoperative complications including pneumothorax and pneumonia. We reviewed 16 trials involving 1455 patients. Patients receiving recruitment maneuvers had a reduced incidence of pulmonary atelectasis (group with recruited pressure >40 cmH2O: risk ratio [RR], 0.20; 95% confidence interval [CI], 0.07-0.57; group with recruited pressure <40 cmH2O: RR, 0.54; 95% CI, 0.33-0.89), reduced incidence of hypoxic events (RR, 0.23; 95% CI, 0.14-0.37), reduced incidence of pneumonia (RR, 0.42; 95% CI, 0.18-0.95), and improved Pao2/Fio2 ratio (weighted mean difference [WMD]; 58.87, 95% CI, 31.24-86.50) without disturbing the cardiac index (WMD, 0.22; 95% CI, -0.18 to 0.61) or mean arterial pressure (WMD, -0.30, 95% CI, -3.19 to 2.59) as compared with those who received conventional mechanical ventilation. The incidence of pneumothorax was nonsignificant between the groups. Recruitment maneuvers may reduce postoperative pulmonary atelectasis, hypoxic events, and pneumonia and improve Pao2/Fio2 ratios without hemodynamic disturbance in patients undergoing cardiac surgery.

Atelectasis in Bariatric Surgery: Review Analysis and Key Practical Recommendations

Obesity is a condition that affects multiple organ systems, particularly the cardiovascular and respiratory system. In recent years, bariatric surgery has been reported to be the gold standard in the treatment of morbid obesity. Body mass index alone is insufficient to predict risks related to anaesthesia and surgery. Obesity contributes to significant postoperative atelectasis and is considered an independent risk factor for postoperative atelectasis owing to decreased functional residual capacity. The treatment and reversibility of atelectasis developed in obese patients undergoing bariatric surgery are challenging. Therefore, an optimisation of pulmonary functions before surgery, lung-sparing ventilation during the perioperative period, awareness of potential postoperative complications and knowledge about preventive measures and therapeutic approaches have become increasingly important in bariatric surgery. The aim of this review was to aid clinicians in the management of atelectasis in patients undergoing bariatric surgery during the perioperative and postoperative period.