Feasibility of an endotracheal tube-mounted camera for percutaneous dilatational tracheostomy.

BACKGROUND: Percutaneous dilatational tracheostomy (PDT) in critically ill patients is often led by optical guidance with a bronchoscope. This is not without its disadvantages. Therefore, we aimed to study the feasibility of a recently introduced endotracheal tube-mounted camera (VivaSight™-SL, ET View, Misgav, Israel) in the guidance of PDT. METHODS: We studied 10 critically ill patients who received PDT with a VivaSight-SL tube that was inserted prior to tracheostomy for optical guidance. Visualization of the tracheal structures (i.e., identification and monitoring of the thyroid, cricoid, and tracheal cartilage and the posterior wall) and the quality of ventilation (before puncture and during the tracheostomy) were rated on four-point Likert scales. Respiratory variables were recorded, and blood gases were sampled before the interventions, before the puncture and before the insertion of the tracheal cannula. RESULTS: Visualization of the tracheal landmarks was rated as 'very good' or 'good' in all but one case. Monitoring during the puncture and dilatation was also rated as 'very good' or 'good' in all but one. In the cases that were rated 'difficult', the visualization and monitoring of the posterior wall of the trachea were the main concerns. No changes in the respiratory variables or blood gases occurred between the puncture and the insertion of the tracheal cannula. CONCLUSION: Percutaneous dilatational tracheostomy with optical guidance from a tube-mounted camera is feasible. Further studies comparing the camera tube with bronchoscopy as the standard approach should be performed.

Influence of prone positioning on the measurement of transpulmonary thermodilution-derived variables in critically ill patients.

BACKGROUND: Patients with respiratory failure undergoing prone positioning (PP) are often monitored by the transpulmonary thermodilution (TPTD) technique. However, it remains unclear whether the measurement of TPTD-derived variables is influenced by PP. We investigated the effects of 135° PP on the accuracy of TPTD-derived variables and their changes over an 8-10 h period of time. METHODS: We studied 16 mechanically ventilated patients who underwent PP for acute respiratory distress syndrome or acute lung injury and received hemodynamic monitoring by the TPTD technique. Measurements of extravascular lung water index (EVLWI), global end-diastolic volume index (GEDVI), ejection fraction corrected GEDVI (cGEDVI), pulmonary vascular permeability index (PVPI) and hemodynamic variables were obtained 10 min before and after positioning and repositioning. One-way analysis of variance and Friedman's test with Student-Newman-Keuls method for all pairwise multiple comparisons were used for statistical analysis. RESULTS: EVLWI increased after proning (12.7 ± 4.7 vs. 14.8 ± 7.8 ml/kg) and remained elevated until end of prone positioning (15.1 ± 7.2 vs. 12.8 ± 4.9 ml/kg) with P < 0.05 for difference between respective time points. After proning, GEDVI remained unchanged (571 ± 153 vs. 593 ± 152 ml/m²). At the end of prone positioning GEDVI was 610 ± 55 ml/m² and decreased after returning to supine to 553 ± 14 ml/m². Proning increased cGEDVI from 525 ± 136 to 570 ± 11 ml/m² and repositioning decreased cGEDVI from 558 ± 116 to 496 ± 121 ml/m². No significant changes in PVPI were observed during the study period. CONCLUSIONS: EVLWI and GEDVI measurements are possibly influenced by prone positioning. In spite of statistical significance, the differences in EVLWI and GEDVI are low and presumably of no clinical relevance.

[Continuous lateral rotational bed therapy in patients with traumatic lung injury: an analysis from the TraumaRegister DGU®]. / Die kontinuierliche laterale Rotationstherapie bei Patienten mit Thoraxtrauma: eine Analyse aus dem TraumaRegister DGU®.

BACKGROUND: Patients with severe thoracic trauma often receive continuous lateral rotational bed therapy (CLRT) for the treatment of lung contusions. In this study, the effects of CLRT on mortality, morbidity and length of stay (LOS) in the intensive care unit (ICU) and in the hospital were evaluated. METHODS: Retrospective data from the TraumaRegister DGU® were analysed, focusing on patients with severe thoracic trauma. Patients treated with CLRT were compared to a control group with comparable trauma severity who had received conventional therapy. RESULTS: A total of 1476 patients (239 with CLRT, 1237 without CLRT) were included in this study. Both groups were similar for demographic characteristics. The median CLRT duration was 6 (4-10) days. Patients receiving CLRT were ventilated for 17 (10-26) days compared to 14 (8-22) days (p = 0.001) in the control group. The ICU length of stay differed significantly (CLRT: 23 [14-32] days; control: 19 [13-28] days; p = 0.002). Also, organ failure occurred more frequently in patients treated with CLRT (CLRT: 76.6%, control: 67.6%; p = 0.006). No differences could be detected regarding mortality rates, multiple organ failure and hospital LOS. CONCLUSIONS: The results of this retrospective analysis fail to detect a benefit for CLRT therapy in trauma patients. Considering inherent limitations of retrospective studies, caution should be exerted when interpreting these results. Further research is warranted to confirm these findings in a prospective trial.

[Airway management in intensive care and emergency medicine : What is new?] / Atemwegssicherung in der Intensiv- und Notfallmedizin : Was gibt es Neues?

In acute respiratory insufficiency, oxygenation and/or ventilation support by mechanical ventilation is an integral part of intensive care and emergency medicine. Effective airway management is essential to prevent hypoxic complications during the securing of the airway. This includes for example the recognition of difficult airways and adequate pre-oxygenation. While the laryngeal tube can be used in the context of cardiopulmonary resuscitation in emergency medicine, endotracheal intubation is standard in intensive care medicine. In addition to direct laryngoscopy (DL), indirect laryngoscopy using video laryngoscopy (VL) is also available. Compared to DL, advantages in intubation success, anticipated difficult airways, and a reduction of mucosa damage have been shown for VL, whereas the advantage for intubation success could only be demonstrated for experienced physicians who should always be present due to the potential complications of intubation. With regard to mortality and incidence of hypoxia, no difference between DL and VL could be shown. According to current data, the VL should not be used preclinically. A tracheostomy is often performed for long-term ventilation. It is still unclear which patients benefit from an early tracheostomy. Usually the bed-side percutaneous dilatation tracheostomy technique is used, which is often performed under bronchoscopic guidance.

Comparison of PulsioFlex® uncalibrated pulse contour method and a modified Fick principle with transpulmonary thermodilution measurements in critically ill patients.

Monitoring of cardiac index (CI) by uncalibrated pulse contour (PC) methods has been shown to be inaccurate in critically ill patients. We tested accuracy and trending of a new pulse contour method and a modified Fick method using central venous oxygen saturation. We studied 21 critically ill and mechanically ventilated patients (age 20-86 years) monitored by PC (PulsioFlex®) and transpulmonary thermodilution (TPTD, PiCCO2®) as reference. At baseline, reference and PC-derived CI (CIPC) were recorded and CI obtained by Fick's method (FM, CIFICK). After four hours, measurements were performed analogously for trending analysis. CI are given in l/min/m2 as mean±standard deviation. At baseline CITPTD was 3.7±0.7, CIPC 3.8±0.7 and CIFICK 5.2±1.8. After 4 hours, CITPTD was 3.5±0.6, CIPC 3.8±1.2 and CIFICK 4.8±1.7. Mean bias for PC at baseline was -0.1 (limits of agreement [LOA] -1.4 to 1.2) and -0.4 (LOA -2.6 to 1.9) after four hours. Percentage errors (PE) were 34% and 60% respectively. FM revealed a bias of -1.5 (LOA -4.8 to 1.8, PE 74%) at baseline and -1.5 (LOA -4.5 to 1.4, PE 68%) at four hours. With an exclusion window of 10% of mean cardiac index, trending analysis by polar plots showed an angular bias of 5° (radial LOA±57°) for PC and 16° (radial LOA±51°) for FM. Although PC values at baseline were marginally acceptable, both methods fail to yield clinically acceptable absolute values. Likewise, trending ability is not adequate for both methods to be used in critically ill patients.