Patient-ventilator asynchrony (PVA) is common in patients receiving noninvasive ventilation (NIV). This occurs primarily when the triggering and cycling-off of ventilatory assistance are not synchronized with the patient's inspiratory efforts and could result in increased work of breathing and niv failure. In general, five types of asynchrony can occur during NIV: ineffective inspiratory efforts, double-triggering, auto-triggering, short-ventilatory cycling, and long-ventilatory cycling. Many factors that affect PVA are mostly related to the degree of air leakage, level of pressure support, and the type and properties of the interface used. Careful monitoring and adjustment of these factors are essential to reduce PVA and improve patient comfort. In this article, we discuss the machine and interface-related factors that influence PVA during NIV and its effect on the respiratory mechanics during pressure support ventilation, which is the ventilatory mode used most commonly during NIV. For that, we critically evaluated studies that assessed ventilator- and interface-related factors that influence PVA during NIV and proposed therapeutic solutions.

BACKGROUND: This cross-sectional case–control study aimed to assess the prevalence of restless legs syndrome (RLS) and its correlates and severity among Arab (Saudi) pregnant women attending antenatal care clinics. METHODS: We interviewed 742 consecutive pregnant women attending antenatal clinics face-to-face using the International RLS Study Group (IRLSSG) criteria. We assessed the severity of RLS using the IRLSSG severity scale for RLS (IRLS). A similar number of age-matched nonpregnant women were enrolled in a control group. RESULTS: Among the cases, 104 (14%) were in the first trimester, 232 (31.3%) in the second trimester, and 406 (54.7%) in the third trimester. The RLS prevalence in cases and controls was 30% and 26.5%, respectively, (P = 0.134). Among cases, severe/very severe RLS was diagnosed in 25% and mild/moderate in 75%, compared with 15% of controls having severe/very severe RLS and 85% having mild/moderate RLS (P < 0.001). Multivariate binary logistic regression analysis identified the following parameters as independent predictors of RLS: parity (odds ratio [OR] 1.113 [confidence intervals [CI] 1.012–1.223], P = 0.027), anemia (OR 1.452 [1.033–2.042], P = 0.03), diabetes mellitus (OR 1.734 [CI 1.084–2.774], P = 0.022), Vitamin D deficiency (OR 2.376 [CI 1.488–3.794],P < 0.001), and smoking (OR 3.839 [CI 1.463–10.074], P = 0.006). None of the cases had been diagnosed or treated for RLS in the antenatal clinics. CONCLUSION: RLS is common, but underdiagnosed, among Saudi pregnant women and nonpregnant women of childbearing age. The study revealed that RLS during pregnancy is linked to parity, anemia, diabetes mellitus, Vitamin D deficiency, and smoking.

BACKGROUND: Organizing pneumonia (OP) usually responds spectacularly well to initial treatment, but relapses can occur and some cases run a fatal course. Still, the issue of relapse has been addressed in relatively few studies, and predictors have not been clarified. The purpose of this study was to examine the pattern of relapses in OP, to determine whether relapse affects morbidity and mortality, and to identify possible predictors of relapse. METHODS: Blood sampling, pulmonary function testing, computed tomography (CT) of the chest, and bronchofiberscopy were performed for all patients and were retrospectively reviewed along with clinical information. Periodical chest CT was conducted and additional chest CT was performed when relapse of OP was clinically suspected. All patients were followed regarding treatment response, treatment duration, and presence of relapse. Results were compared between two groups based on serum concentrations of surfactant protein (SP)-D: normal SP-D and high SP-D. RESULTS: Twenty-two patients were analyzed in this study. SP-D showed a negative correlation with percutaneous oxygen saturation and positive correlations with serum lactate dehydrogenase, Krebs von den Lungen (KL)-6, and percentage of lymphocytes in bronchoalveolar lavage (BAL). Prognosis was good for all patients, but relapse was significantly more frequent in the high SP-D group (6 cases) than in the normal SP-D group (0 cases; P = 0.049). Serum KL-6 and percentage of monocytes in BAL were significantly higher, and pulmonary vital capacity and forced expiratory volume in 1 s were significantly lower in the high SP-D group than in the low SP-D group. CONCLUSIONS: When treating cases of OP with high serum concentrations of SP-D, attention should be paid to the possibility of relapse.

BACKGROUND: Congenital lobar emphysema (CLE) is a rare developmental malformation of the lung but can be associated with high morbidity and mortality. The objective of this study is to review our experience with 45 patients with CLE highlighting clinical features, aspects of diagnosis, and management. METHODS: The medical records of all patients diagnosed with CLE in our center were reviewed. Patients age at the time of diagnosis, sex, clinical presentation, associated anomalies, the lobes affected, treatment modality, and outcome were described. A comparison was made between those who had lobectomy via open thoracotomy and those treated thoracoscopically. RESULTS: From January 2000 to December 2018, a total of 45 infants with CLE were presented to our institution. There were 30 male and 15 female, and the mean age at presentation was 3.35 months. Twenty-five patients presented with respiratory distress. Nine patients presented immediately after birth, and two of them had surgery within the 1^st week of life. Twenty patients were presented with repeated chest infections. Left upper lobe was affected in 27 patients, right middle lobe in 13, and right upper lobe in 5 patients. Forty-four patients had a lobectomy, and one was managed conservatively. One patient had a postoperative bronchopleural fistula. Nine patients had a thoracoscopic lobectomy, and two of them were converted to open thoracotomy because of persistent air leak. The operative time and hospital stay were nonsignificantly longer in thoracoscopic lobectomy (P = 0.5 and 0.4, respectively). There was no operative mortality in both groups. CONCLUSIONS: CLE is a rare malformation with variable presentation. Infants presenting with respiratory distress or recurrent chest infection should be evaluated for the possibility of CLE. Lobectomy is the treatment of choice, and rarely, the patients may be managed conservatively. Thoracoscopic lobectomy is a safe procedure with the possibility of air leak and conversion to open lobectomy.

BACKGROUND: Bronchiectasis is common in patients with advanced chronic obstructive pulmonary disease (COPD) and adversely affects the patients' clinical condition. This study aimed to investigate the effects of bronchiectasis on exercise capacity, dyspnea perception, disease-specific quality of life, and psychological status in patients with COPD and determine the extent of these adverse effects by the severity of bronchiectasis. METHODS: A total of 387 COPD patients (245 patients with only COPD [Group 1] and 142 COPD patients with accompanying bronchiectasis [Group 2]) were included in the study. The patients in Group 2 were divided into three subgroups as mild, moderate, and severe using the Bronchiectasis Severity Index. Six-minute walk distance, dyspnea perception, St. George's Respiratory Questionnaire (SGRQ), and hospital anxiety and depression scores were compared between the groups. RESULTS: In Group 2, dyspnea perception, SGRQ total scores, depression score were higher, and walking distance was lower (P = 0.001, P = 0.007, P = 0.001, and P = 0.011, respectively). Group 2 had significantly worse arterial blood gas values. Dyspnea perception increased with the increasing severity in Group 2 (P < 0.001). Walking distance was lower in patients with severe bronchiectasis (P < 0.001). SGRQ total score, anxiety, and depression scores were significantly higher in the severe subgroup (P < 0.001, P = 0.003, and P = 0.002, respectively). CONCLUSIONS: In patients with Stage 3 and 4 COPD, the presence of bronchiectasis adversely affects the clinical status of the patients, decreases their exercise capacity, deteriorates their quality of life, and disrupts their psychological status. Investigating the presence of bronchiectasis in COPD patients is crucial for early diagnosis and proper treatment.

BACKGROUND: The prevalence of latent tuberculosis infection (LTBI) has been found to be high among students undergoing clinical training. The aim of this study is to determine the incidence of LTBI among undergraduate health science students after their clinical training and to compare the risk between different college specialties. METHODS: This is a retrospective cohort study of students who completed their clinical training from 2010 to 2017. The risk of LTBI was defined based on the conversion of tuberculin skin test (TST) results from negative at the start of training to positive after the completion of training. RESULTS: A total of 2000 students were evaluated, of whom 1997 were included in this analysis. Six percent tested positive in the first TST of the initial screening. Ten percent of students with a normal baseline TST converted to positive on the follow-up TST. Clinical training in the college of medicine increased the risk of LTBI by 76% (odds ratio: 1.76; 95% confidence interval: 1.04– 2.96; P = 0.03) compared to clinical training in other medical colleges. CONCLUSIONs: The risk of acquiring LTBI during clinical training in health science colleges is 10%. Students in the college of medicine are at significantly higher risk of LTBI than students of other health science specialties.

Mediastinal nonseminomatous germ cell tumor (NSGCT) is rare. NSGCT shows excellent response to cisplatin-based chemotherapy. However, some tumors continue to enlarge despite normal tumor markers after chemotherapy, a rare condition called growing teratoma syndrome (GTS). Recognition of this condition is imperative for prompt surgical resection to prevent further cardiopulmonary compression and to improve survival. Multidisciplinary team meeting is important for perioperative preparation and care to improve the outcome of this high-risk surgery. Here, we report two cases of mediastinal GTS and underwent surgical resection, of which one died of pericardial decompression syndrome and the other is well.

Human T-cell lymphotropic virus type-1 (HTLV-1)-associated bronchioloalveolar disorders (HABAs) are pulmonary disorders with various interstitial lung disease patterns that often occur in HTLV-1 carriers. Among HABAs, organizing pneumonia (OP) is extremely rare. We present a case of an 82-year-old woman with OP as a HABA. This patient responded to corticosteroid therapy; however, the patient required the continuation of oral corticosteroid therapy to avoid OP relapse. In cases of OP as a HABA that are not stabilized by treatment with corticosteroids, continuation of oral corticosteroid therapy might be considered.