Nasogastric tube in mechanical ventilated patients: ETCO2 and pH measuring to confirm correct placement. A pilot study.

INTRODUCTION: Nasogastric tube (NGT) placement is a procedure commonly performed in mechanically ventilated (MV) patients. Chest X-Ray is the diagnostic gold-standard to confirm its correct placement, with the downsides of requiring MV patients' mobilization and of intrinsic actinic risk. Other potential methods to confirm NGT placement have shown lower accuracy compared to chest X-ray; end-tidal CO2 (ETCO2) and pH analysis have already been singularly investigated as an alternative to the gold standard. Aim of this study was to determine threshold values in ETCO2 and pH measurement at which correct NGT positioning can be confirmed with the highest accuracy. MATERIALS & METHODS: This was a prospective, multicenter, observational trial; a continuous cohort of eligible patients was allocated with site into two arms. Patients underwent general anesthesia, orotracheal intubation and MV; in the first and second group we respectively assessed the difference between tracheal and esophageal ETCO2 and between esophageal and gastric pH values. RESULTS: From November 2020 to March 2021, 85 consecutive patients were enrolled: 40 in the ETCO2 group and 45 in the pH group. The ETCO2 ROC analysis for predicting NGT tracheal misplacement demonstrated an optimal ETCO2 cutoff value of 25.5 mmHg, with both sensitivity and specificity reaching 1.0 (AUC 1.0, p < 0.001). The pH ROC analysis for predicting NGT correct gastric placement resulted in an optimal pH cutoff value of 4.25, with mild diagnostic accuracy (AUC 0.79, p < 0.001). DISCUSSION: In patients receiving MV, ETCO2 and pH measurements respectively identified incorrect and correct NGT placement, allowing the identification of threshold values potentially able to improve correct NGT positioning. TRIAL REGISTRATION: NCT03934515 (www.clinicaltrials.gov).

Listeria monocytogenes L-forms respond to cell wall deficiency by modifying gene expression and the mode of division.

Cell wall-deficient bacteria referred to as L-forms have lost the ability to maintain or build a rigid peptidoglycan envelope. We have generated stable, non-reverting L-form variants of the Gram-positive pathogen Listeria monocytogenes, and studied the cellular and molecular changes associated with this transition. Stable L-form cells can occur as small protoplast-like vesicles and as multinucleated, large bodies. They have lost the thick, multilayered murein sacculus and are surrounded by a cytoplasmic membrane only, although peptidoglycan precursors are still produced. While they lack murein-associated molecules including Internalin A, membrane-anchored proteins such as Internalin B are retained. Surprisingly, L-forms were found to be able to divide and propagate indefinitely without a wall. Time-lapse microscopy of fluorescently labelled L-forms indicated a switch to a novel form of cell division, where genome-containing membrane vesicles are first formed within enlarged L-forms, and subsequently released by collapse of the mother cell. Array-based transcriptomics of parent and L-form cells revealed manifold differences in expression of genes associated with morphological and physiological functions. The L-forms feature downregulated metabolic functions correlating with the dramatic shift in surface to volume ratio, whereas upregulation of stress genes reflects the difficulties in adapting to this unusual, cell wall-deficient lifestyle.

Hospital Disaster Preparedness in Switzerland Over a Decade: A National Survey.

OBJECTIVE: The present study aimed to provide a comprehensive assessment of Swiss hospital disaster preparedness in 2016 compared with the 2006 data. METHODS: A questionnaire was addressed in 2016 to all heads responsible for Swiss emergency departments (EDs). RESULTS: Of the 107 hospitals included, 83 (78%) returned the survey. Overall, 76 (92%) hospitals had a plan in case of a mass casualty incident, and 76 (93%) in case of an accident within the hospital itself. There was a lack in preparedness for specific situations: less than a third of hospitals had a specific plan for nuclear/radiological, biological, chemical, and burns (NRBC+B) patients: nuclear/radiological (14; 18%), biological (25; 31%), chemical (27; 34%), and burns (15; 49%), and 48 (61%) of EDs had a decontamination area. Less than a quarter of hospitals had specific plans for the most vulnerable populations during disasters, such as seniors (12; 15%) and children (19; 24%). CONCLUSIONS: The rate of hospitals with a disaster plan has increased since 2006, reaching a level of 92%. The Swiss health care system remains vulnerable to specific threats like NRBC. The lack of national legislation and funds aimed at fostering hospitals' preparedness to disasters may be the root cause to explain the vulnerability of Swiss hospitals regarding disaster medicine. (Disaster Med Public Health Preparedness. 2019;13:433-439).