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Introduction Methods Results Conclusion The aim of this study was to clarify the safety and efficacy of breath‐hold irradiation in liver stereotactic body radiotherapy (SBRT).A retrospective analysis was conducted on 57 consecutive patients who received SBRT for hepatocellular carcinoma or liver metastases between 2013 and 2021. Breath‐hold irradiation was implemented for patients treated after April 2020.The median follow‐up period for all patients was 16.4 months (IQR: 7.36–20.9). The 2‐year overall survival rate was 64.4% (95% CI: 47.4–77.2), and the local control rate was 84.3% (95% CI: 69.7–92.3) for all patients. The 1‐year overall survival was 80.0% (95% CI: 60.8–90.5) versus 82.0% (95% CI: 53.5–93.9) in the free‐respiratory (FR) group versus the breath‐hold (BH) group, respectively (P = 0.60). The 1‐year local control rates were 78.1% (95% CI: 57.5–89.5) in the FR group and 95.7% (95% CI: 72.9–99.4) in the BH group, respectively (P = 0.16). Radiation‐induced liver injury, defined by an escalation of ≥2 in Child–Pugh score, was observed in four patients within each group (FR 13% vs. BH 15%). There were no gastrointestinal adverse events of Grade 3 or higher.Breath‐hold irradiation can be safely administered and has demonstrated clinical potential in improving local control. Further research into dose escalation using breath‐hold techniques is warranted. [ABSTRACT FROM AUTHOR]

Purpose: For many thoracic tumors, patient respiration can introduce a significant amount of variability in tumor position that must be accounted for during radiotherapy. Of all existing techniques, real-time dynamic tumor tracking (DTT) represents the most ideal motion management strategy but can be limited by the treatment delivery technique. Our objective was to analyze the dosimetric performance of a dynamic conformal arc (DCA) approach to tumor tracking on standard linear accelerators that may offer similar dosimetric benefit, but with less complexity compared to intensity-modulated radiation therapy (IMRT) or volumetric modulated arc therapy (VMAT). Methods: Ten patients who previously received free-breathing VMAT for lung cancer were retrospectively analyzed. Patient 4D-CT and respiratory traces were simultaneously acquired prior to treatment and re-planned with DCA and VMAT using the Eclipse v15.6 Treatment Planning System with gated, deep inspiration breath hold (DIBH), and motion encompassment techniques taken into consideration, generating seven new plans per patient. DTT with DCA was simulated using an in-house MATLAB script to parse the radiation dose into each phase of the 4D-CT based on the patient's respiratory trace.Dose distributions were normalized to the same prescription and analyzed using dose volume histograms (DVHs).DVH metrics were assessed using ANOVA with subsequent paired t-tests. Results: The DCA-based DTT plans outperformed or showed comparable performance in their DVH metrics compared to all other combinations of treatment techniques while using motion management in normal lung sparing (p < 0.05). Normal lung sparing was not significantly different when comparing DCA-based DTT to gated and DIBH VMAT (p > 0.05), while both outperformed the corresponding DCA plans (p < 0.05). Simulated treatment times using DCA-based DTT were significantly shorter than both gating and DIBH plans (p < 0.05). Conclusions: A DCA-based DTT technique showed significant advantages over conventional motion encompassment treatments in lung cancer radiotherapy, with comparable performance to stricter techniques like gating and DIBH while conferring greater time-saving benefits. [ABSTRACT FROM AUTHOR]

Background: Patient positioning is an independent nursing intervention and may increase peripheral oxygenation for patients with lung disease. Few studies have been conducted on the effect of body positions on oxygenation in patients with lung disease. Aims and objectives: To investigate the effects of five different positions on peripheral oxygen saturation (SpO2) and vital signs in patients with lung disease. Design: A semi‐experimental study was conducted. Methods: Consecutive samples were recorded from critical care patients followed in the chest clinic of a university hospital. A total of 109 patients with lung disease were recruited. Patients who were able to lie in all positions, and who had unilateral or bilateral lung disease documented by a medical diagnosis by a physician were included in this study. The SpO2 and vital signs were measured at each position three times. Results: For patients with right, left, and bilateral lung disease, lying on the right side of the body at 45 in bed, the SpO2 was higher, but this difference was not statistically significant. There was a significant difference at 40 minutes between the pulse rate in patients with left and bilateral lung disease, but not in patients with right lung disease. No significant differences were found between respiratory rates and body temperature in patients in any of the three groups at 10, 25, and 40 minutes. Conclusions: Although this difference was not statistically significant, lying on the right side of the body at 45 in bed can be an effective position for improving oxygenation in all patients with lung disease. Relevance to Clinical Practice: As there is insufficient evidence to suggest a specific position, further studies are needed. This study provides evidence that the best oxygenation in patients with unilateral and bilateral lung disease can be obtained by determining the appropriate position for critical care nurses. [ABSTRACT FROM AUTHOR]

Aim: To investigate the characteristics of infants with neonatal encephalopathy (NE) receiving therapeutic hypothermia (TH) who developed late onset oxygen requirement during or after rewarming.Methods: Infants were stratified by receiving (a) new onset isolated oxygen requirements during or after rewarming; (b) no respiratory support during hospital stay; and (c) invasive and/or non-invasive respiratory support before or during cooling.Results: Of 136 infants treated with TH, 49 (36%) did not require any respiratory support, and 78 (57.4%) received invasive or non-invasive support before or during cooling. Nine infants (6.6%) developed late onset oxygen requirement. The late onset oxygen requirement started at median age of 3.8 days (IQR 3.6-5.2) and ended at median 7.5 days (IQR 5.8-12.7). Total hours of O2 exposure were median 62.0 (IQR 24.4-112.6). Maximum support was low-flow nasal cannula from 100% oxygen source with a flow rate of 40-250 mL/min. Infants in this group had higher Apgar scores, milder metabolic acidosis and no seizures. Three infants had diagnostic investigations without significant findings.Conclusion: A small percentage of neonates with NE developed late onset oxygen requirement during or after rewarming. Late oxygen requirement was associated with evidence of less severe perinatal hypoxia-ischaemia. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the detectability of fiducial markers' positions for real‐time target tracking system equipping with a standard linac. The hypothesis is that the detectability depends on the type of fiducial marker and the gantry angle of acquired triggered images. Methods: Three types of ball fiducials and four slim fiducials with lengths of 3 and 5 mm were prepared for this study. Triggered images with three similar fiducials were acquired at every 10° during the conformal arc irradiation to detect the target position. Although only one type of arrangement was prepared for the ball fiducials, a three‐type arrangement was prepared for the slim fiducials, such as parallel, orthogonal, and oblique with 45° to the gantry‐couch direction. To measure the detectability of the real‐time target tracking system for each fiducial and arrangement, detected marker positions were compared with expected marker positions at every angle of acquired triggered images. Results: For the ball‐type fiducial, the maximum difference between the detected marker positions and expected marker positions was 0.3 mm in all directions. For the slim fiducial arranged parallel and oblique with 45°, the maximum difference was 0.4 mm in all directions. When each slim fiducial was arranged orthogonal to the gantry‐couch direction, the maximum difference was 1.5 mm for the length of 3 mm, and 3.2 mm for the length of 5 mm. Conclusions: The detectability of fiducial markers' positions for the real‐time target tracking system equipping with a standard linac depends on the form and insertion angles of the fiducials. [ABSTRACT FROM AUTHOR]

Aim: This study aimed to explore the perceptions of the highly specialized nurses who provided extracorporeal membrane oxygenation therapy for the mostly young and critically ill patients during the 2009 H1N1 pandemic. Background: The 2009 influenza A (H1N1) virus caused a global pandemic and also affected New Zealand during that winter. Nine H1N1-infected adult patients with severe acute respiratory distress syndrome were admitted into an intensive care unit of a large urban hospital for rescue extracorporeal membrane oxygenation therapy. Design: The study used a two-phase mix methods study design. Methods: Phase 1 of the study involved five nurses attending a focus group interview to collect their views of the challenges and issues of caring for these patients. The results of the focus group were used to formulate the phase 2 survey. In total, 25 eligible nurses were invited to complete an anonymous survey; 18 completed and returned surveys giving a 72% response rate. Results: The survey identified issues including the acuity and high mortality rate of those affected, nurses working in an isolated environment because of infection control requirements, limited support and being asked to work extra shifts. Conclusion: Despite these challenges, the nurses felt positive about their experience of caring for the H1N1 patients, and felt the experience advanced their skills and improved job satisfaction. Relevance to Clinical Practice: For future pandemics, this study identified the need for all staff to have a basic understanding of extracorporeal membrane oxygenation; strengthen inter-professional collaboration and communication; provision for more support and recognition of these highly specialized nurses, along with providing regular pandemic updates and offering counselling services. [ABSTRACT FROM AUTHOR]