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BACKGROUND: Vision-based pulmonary diagnostics present a unique approach for tracking and measuring natural breathing behaviors through remote imaging. While many existing methods correlate chest and diaphragm movements to respiratory behavior, we look at how the direct visualization of thermal CO2 exhale flow patterns can be tracked to directly measure expiratory flow. METHODS: In this work, we present a novel method for isolating and extracting turbulent exhale flow signals from thermal image sequences through flow-field prediction and optical flow measurement. The objective of this work is to introduce a respiratory diagnostic tool that can be used to capture and quantify natural breathing, to identify and measure respiratory metrics such as breathing rate, flow, and volume. One of the primary contributions of this work is a method for capturing and measuring natural exhale behaviors that describe individualized pulmonary traits. By monitoring subtle individualized respiratory traits, we can perform secondary analysis to identify unique personalized signatures and abnormalities to gain insight into pulmonary function. In our study, we perform data acquisition within a clinical setting to train an inference model (FieldNet) that predicts flow-fields to quantify observed exhale behaviors over time. RESULTS: Expiratory flow measurements capturing individualized flow signatures from our initial cohort demonstrate how the proposed flow field model can be used to isolate and analyze turbulent exhale behaviors and measure anomalous behavior. CONCLUSIONS: Our results illustrate that detailed spatial flow analysis can contribute to unique signatures for identifying patient specific natural breathing behaviors and abnormality detection. This provides the first-step towards a non-contact respiratory technology that directly captures effort-independent behaviors based on the direct measurement of imaged CO2 exhaled airflow patterns.
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Aim: The 2021 European Resuscitation Council (ERC) guidelines recommend two automated external defibrillators (AEDs)/km2 and at least 10 first responders/km2. We examined 1) access to AEDs and volunteer first responders in line with these guidelines and 2) its associations with socioeconomic factors and income inequality, focusing on small spatial scales. Method: We considered data on 776 AEDs in February 2022 and 1,173 out-of-hospital cardiac arrests (OHCAs) including 713 OHCA with app-alerted volunteer first responders from February to September 2022 in Berlin. We fit multilevel models to analyse AED area coverage and Poisson models to examine first responder availability across 12 districts and 536 neighbourhoods. Results: Median AED area coverage according to the 2021 ERC guidelines was 43.1% (interquartile range (IQR) 2.3-87.2) at the neighbourhood level and median number of available first responders per OHCA case was one (IQR 0.0-1.0). AED area coverage showed a positive association with average income tax per capita, with better coverage in the highest compared to the lowest quartile neighbourhoods (coefficient: 0.13, 95% confidence interval (CI): 0.01-0.25). First responder availability was not associated with income tax. AED area coverage and first responder availability were positively associated with income inequality, with better coverage (coefficient: 0.13, 95% CI: 0.04-0.23) and availability (rate ratio: 1.31, 95% CI: 1.03-1.67) in quartiles of highest as compared to lowest inequality. Conclusion: Access to resuscitation resources is neither equitable nor in accordance with the 2021 ERC guidelines. Ensuring better access necessitates understanding of socioeconomic factors and income inequality at small spatial scales.
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BACKGROUND: Mechanical power (MP), the rate of mechanical energy (ME) delivery, is a recently introduced unifying ventilator parameter consisting of tidal volume, airway pressures, and respiratory rates, which predicts pulmonary complications in several clinical contexts. However, ME has not been previously studied in the perioperative context, and neither parameter has been studied in the context of thoracic surgery utilizing one-lung ventilation. METHODS: The relationships between ME variables and postoperative pulmonary complications were evaluated in this post hoc analysis of data from a multicenter randomized clinical trial of lung resection surgery conducted between 2020 and 2021 (n = 1,170). Time-weighted average MP and ME (the area under the MP time curve) were obtained for individual patients. The primary analysis was the association of time-weighted average MP and ME with pulmonary complications within 7 postoperative days. Multivariable logistic regression was performed to examine the relationships between energy variables and the primary outcome. RESULTS: In 1,055 patients analyzed, pulmonary complications occurred in 41% (431 of 1,055). The median (interquartile ranges) ME and time-weighted average MP in patients who developed postoperative pulmonary complications versus those who did not were 1,146 (811 to 1,530) J versus 924 (730 to 1,240) J (P < 0.001), and 6.9 (5.5 to 8.7) J/min versus 6.7 (5.2 to 8.5) J/min (P = 0.091), respectively. ME was independently associated with postoperative pulmonary complications (ORadjusted, 1.44 [95% CI, 1.16 to 1.80]; P = 0.001). However, the association between time-weighted average MP and postoperative pulmonary complications was time-dependent, and time-weighted average MP was significantly associated with postoperative pulmonary complications in cases utilizing longer periods of mechanical ventilation (210 min or greater; ORadjusted, 1.46 [95% CI, 1.11 to 1.93]; P = 0.007). Normalization of ME and time-weighted average MP either to predicted body weight or to respiratory system compliance did not alter these associations. CONCLUSIONS: ME and, in cases requiring longer periods of mechanical ventilation, MP were independently associated with postoperative pulmonary complications in thoracic surgery.
Subject(s)
One-Lung Ventilation , Positive-Pressure Respiration , Humans , Positive-Pressure Respiration/adverse effects , Lung , Respiration, Artificial/adverse effects , Postoperative Complications/epidemiology , Postoperative Complications/etiology , Tidal Volume , One-Lung Ventilation/adverse effectsABSTRACT
OBJECTIVES: Although patient-controlled epidural analgesia (PCEA) is an effective form of regional analgesia for abdominal surgery, some patients experience significant rebound pain after the discontinuation of PCEA. However, risk factors for rebound pain associated with PCEA in major abdominal surgery remain unknown. This study evaluated the incidence of rebound pain related to PCEA and explored potential associated risk factors. MATERIALS AND METHODS: We performed a retrospective review of 236 patients using PCEA following hepatobiliary and pancreas surgery between 2018 and 2020 in a tertiary hospital in South Korea. Rebound pain was defined as an increase from well-controlled pain (numeric rating scale <4) during epidural analgesia to severe pain (numeric rating scale ≥7) within 24 hours of discontinuation of PCEA. Logistic regression analysis was performed to determine the factors associated with rebound pain. RESULTS: Patients were categorized into the nonrebound pain group (170 patients; 72%) and the rebound pain group (66 patients; 28%). Multivariable logistic regression analysis revealed that preoperative prognostic nutritional index below 45 (odds ratio=2.080, 95% confidential interval=1.061-4.079, P =0.033) and intraoperative transfusion (odds ratio=4.190, 95% confidential interval=1.436-12.226, P =0.009) were independently associated with rebound pain after PCEA discontinuation. DISCUSSION: Rebound pain after PCEA occurred in ~30% of patients who underwent major abdominal surgery, resulting in insufficient postoperative pain management. Preoperative low prognostic nutritional index and intraoperative transfusion may be associated with rebound pain after PCEA discontinuation.
Subject(s)
Analgesia, Epidural , Analgesia, Epidural/adverse effects , Analgesia, Epidural/methods , Analgesia, Patient-Controlled/methods , Humans , Pain Measurement , Pain, Postoperative/drug therapy , Pain, Postoperative/etiology , Retrospective StudiesABSTRACT
BACKGROUND: The fluoroscopic-guided epidural access is occasionally challenging; therefore, the contralateral oblique (CLO) view has emerged as an alternative approach. The CLO view appears to be optimal for mid-thoracic epidural access; however, evidence on its utility is lacking. Therefore, we aimed to evaluate the clinical usefulness of the CLO view at 60°±5° compared with the lateral (LAT) view using fluoroscopic-guided mid-thoracic epidural access. METHODS: Patients were randomly allocated to undergo mid-thoracic epidural access under the fluoroscopic LAT view (LAT group) or CLO view (CLO group). The primary outcome was the first-pass success rate of mid-thoracic epidural access. The secondary outcomes were procedural pain intensity, patient satisfaction, needling time, number of needle passes, and radiation dose. RESULTS: Seventy-nine patients were included. The first-pass success rate was significantly higher in the CLO group than in the LAT group (68.3% vs 34.2%, difference: 34.1%; 95% CI 13.3 to 54.8; p=0.003). Procedural pain intensity was significantly lower in the CLO group than in the LAT group. Patient satisfaction was signiï¬cantly greater in the CLO group than in the LAT group. The needling time and the number of needle passes were significantly lower in the CLO group than in the LAT group. Radiation dose in the CLO group was significantly reduced compared with that in the LAT group. CONCLUSIONS: The fluoroscopic CLO view at 60°±5° increased the success rate and patient satisfaction and reduced the procedural time and patient discomfort compared with the LAT view when performing mid-thoracic epidural access. Therefore, the CLO view at 60°±5° can be considered for mid-thoracic epidural access under fluoroscopic guidance. TRIAL REGISTRATION NUMBER: KCT0004926.
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BACKGROUND: The use of a public access defibrillator (PAD) increases the probability of surviving an out-of-hospital cardiac arrest (OHCA). No strategies exist, however, for the optimal distribution of PADs in an urban area in order to meet existing needs and ensure equal access for all potential users. It thus seems likely that the accessibility of PADs on the spatial level varies widely as a function of living circumstances. METHODS: This cross-sectional study is based on registry data concerning PAD (2022, n = 776) and OHCA (2018-2020, n = 4051), along with data on socioeconomic factors on the spatial level in Berlin (12 districts and 137 subdistricts). Associations of socioeconomic factors with the number of PADs per 10 000 inhabitants and the PAD coverage rate of sites of previous OHCAs were investigated. RESULTS: The median number of PADs per 10 000 inhabitants ranged from 0.46 to 2.67 at the district level, and only five districts had a median PAD coverage rate of sites of previous OHCAs above 0%, after aggregation of the analyses at the subdistrict level. Subdistricts with a more favorable economic status and a greater income disparity had a higher PAD density. Socially disadvantaged subdistricts had no association with PAD density. CONCLUSION: There are large deficits in the distribution of PADs at the small-scale spatial level in Berlin with respect to the goals of meeting existing needs and ensuring equal access for all potential users. The findings presented here will be of importance for the planning of future PAD programs so that the distributional efficiency and fairness of PAD in urban areas can be improved.
Subject(s)
Cardiopulmonary Resuscitation , Out-of-Hospital Cardiac Arrest , Berlin/epidemiology , Cardiopulmonary Resuscitation/methods , Cross-Sectional Studies , Defibrillators , Humans , Out-of-Hospital Cardiac Arrest/epidemiology , Out-of-Hospital Cardiac Arrest/therapy , Socioeconomic FactorsABSTRACT
Although recent evidence shows that the programmed intermittent epidural bolus can provide improved analgesia compared to continuous epidural infusion during labor, its usefulness in major upper abdominal surgery remains unclear. We evaluated the effect of programmed intermittent epidural bolus versus continuous epidural infusion on the consumption of postoperative rescue opioids, pain intensity, and consumption of local anesthetic by retrospective analysis of data of patients who underwent major upper abdominal surgery under ultrasound-assisted thoracic epidural analgesia between July 2018 and October 2020. The primary outcome was total opioid consumption up to 72 h after surgery. The data of postoperative pain scores, epidural local anesthetic consumption, and adverse events from 193 patients were analyzed (continuous epidural infusion: n = 124, programmed intermittent epidural bolus: n = 69). There was no significant difference in the rescue opioid consumption in the 72 h postoperative period between the groups (33.3 mg [20.0-43.3] vs. 28.3 mg [18.3-43.3], p = 0.375). There were also no significant differences in the pain scores, epidural local anesthetic consumption, and incidence of adverse events. Our findings suggest that the quality of postoperative analgesia and safety following major upper abdominal surgery were comparable between the groups. However, the use of programmed intermittent epidural bolus requires further evaluation.
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BACKGROUND AND OBJECTIVE: Thoracic epidural analgesia can significantly reduce acute postoperative pain. However, thoracic epidural catheter placement is challenging. Although real-time ultrasound (US)-guided thoracic epidural catheter placement has been recently introduced, data regarding the accuracy and technical description are limited. Therefore, this prospective observational study aimed to assess the success rate and describe the technical considerations of real-time US-guided low thoracic epidural catheter placement. METHODS: 38 patients in the prone position were prospectively studied. After the target interlaminar space between T9 and T12 was identified, the needle was advanced under real-time US guidance and was stopped just short of the posterior complex. Further advancement of the needle was accomplished without US guidance using loss-of-resistance techniques to normal saline until the epidural space was accessed. Procedure-related variables such as time to mark space, needling time, number of needle passes, number of skin punctures, and the first-pass success rate were measured. The primary outcome was the success rate of real-time US-guided thoracic epidural catheter placement, which was evaluated using fluoroscopy. In addition, the position of the catheter, contrast dispersion, and complications were evaluated. RESULTS: This study included 38 patients. The T10-T11 interlaminar space was the most location for epidural access. During the procedure, the mean time for marking the overlying skin for the procedure was 49.5±13.8 s and the median needling time was 49 s. The median number of needle passes was 1.0 (1.0-1.0). All patients underwent one skin puncture for the procedure. The first-pass and second-pass success rates were 76.3% and 18.4%, respectively. Fluoroscopic evaluation revealed that the catheter tips were all positioned in the epidural space and were usually located between T9 and T10 (84.2%). The cranial and caudal contrast dispersion were observed up to 5.4±1.6 and 2.6±1.0 vertebral body levels, respectively. No procedure-related complications occurred. CONCLUSION: Real-time US guidance appears to be a feasible option for facilitating thoracic epidural insertion. Whether or not this technique improves the procedural success and quality compared with landmark-based techniques will require additional study. TRIAL REGISTRATION NUMBER: NCT03890640.
Subject(s)
Catheters , Epidural Space , Epidural Space/diagnostic imaging , Fluoroscopy , Humans , Prospective Studies , Ultrasonography, InterventionalABSTRACT
BACKGROUND: Generally, lactate levels > 2 mmol/L represent hyperlactatemia, whereas lactic acidosis is often defined as lactate > 4 mmol/L. Although hyperlactatemia is common finding in liver transplant (LT) candidates, association between lactate and organ failures with Acute-on-chronic Liver Failure (ACLF) is poorly studied. We searched the important variables for pre-LT hyperlactatemia and examined the impact of preoperative hyperlactatemia on early mortality after LT. METHODS: A total of 2,002 patients from LT registry between January 2008 and February 2019 were analyzed. Six organ failures (liver, kidney, brain, coagulation, circulation, and lung) were defined by criteria of EASL-CLIF ACLF Consortium. Variable importance of preoperative hyperlactatemia was examined by machine learning using random survival forest (RSF). Kaplan-Meier Survival curve analysis was performed to assess 90-day mortality. RESULTS: Median lactate level was 1.9 mmol/L (interquartile range: 1.4, 2.4 mmol/L) and 107 (5.3%) patients showed > 4.0 mmol/L. RSF analysis revealed that the four most important variables for hyperlactatemia were MELD score, circulatory failure, hemoglobin, and respiratory failure. The 30-day and 90-day mortality rates were 2.7% and 5.1%, whereas patients with lactate > 4.0 mmol/L showed increased rate of 15.0% and 19.6%, respectively. CONCLUSIONS: About 50% and 5% of LT candidates showed pre-LT hyperlactatemia of > 2.0 mmol/L and > 4.0 mmol/L, respectively. Pre-LT lactate > 4.0 mmol/L was associated with increased early post-LT mortality. Our results suggest that future study of correcting modifiable risk factors may play a role in preventing hyperlactatemia and lowering early mortality after LT.
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The goal was to examine the accessibility of Ia-proprioceptive pathways to motoneurons of leg muscles associated with gait in infants with Myelomeningocele (MMC). Participants were 15 MMC infants, ages 2-10 months. We assessed over repeated trials, the tendon reflex (T-reflex), vibration-induced inhibition of T-reflex (VIM-T-reflex), and tonic vibration-induced reflex (VIR) when computer controlled stimuli were applied to the three gait muscles of each leg. Only one third of MMC infants exhibited motor responses following the mechanical stimuli with sufficient frequency to be judged functioning as in typically developing (TD) infants. Age and lesion level were not apparently associated with response frequency, but scores on the gross motor portion of the Bayley Scale was a reasonable predictor. For those in which responses were frequent, the pattern of reciprocal excitation was similar to that of age-matched TD infants. 4 of the 10 non-responders who were also tested for their responses to being supported on a pediatric treadmill in a companion study showed voluntary muscle activity in all three gait muscles and a vibration-induced contraction was observed for some of the non-responders. Ia-proprioceptive pathways to homonymous and heteronymous muscles are functioning in some MMC babies, but the gain setting of these pathways were generally depressed and for many there was no evidence that the pathways were intact, although for some group more functional stimuli may be needed to elicit responses and experience may be needed to enhance the gain on the sensitivity of these neural pathways. More research is needed to understand how to optimize outcomes via rehabilitation.
Subject(s)
Meningomyelocele/physiopathology , Muscle, Skeletal/physiology , Proprioception/physiology , Reflex, Stretch/physiology , Electromyography/methods , Female , Humans , Infant , Leg/physiology , Male , Neural Pathways/physiology , VibrationABSTRACT
UNLABELLED: Jung T, Lee D, Charalambous C, Vrongistinos K. The influence of applying additional weight to the affected leg on gait patterns during aquatic treadmill walking in people poststroke. OBJECTIVE: To investigate how the application of additional weights to the affected leg influences gait patterns of people poststroke during aquatic treadmill walking. DESIGN: Comparative gait analysis. SETTING: University-based aquatic therapy center. PARTICIPANTS: Community-dwelling volunteers (n=22) with chronic hemiparesis caused by stroke. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Spatiotemporal and kinematic gait parameters. RESULTS: The use of an ankle weight showed an increase in the stance phase percentage of gait cycle (3%, P=.015) when compared with no weight. However, the difference was not significant after a Bonferroni adjustment was applied for a more stringent statistical analysis. No significant differences were found in cadence and stride length. The use of an ankle weight showed a significant decrease of the peak hip flexion (7.9%, P=.001) of the affected limb as compared with no weight condition. This decrease was marked as the reduction of unwanted limb flotation because people poststroke typically show excessive hip flexion of the paretic leg in the late swing phase followed by fluctuating hip movements during aquatic treadmill walking. The frontal and transverse plane hip motions did not show any significant differences but displayed a trend of a decrease in the peak hip abduction during the swing phase with additional weights. The use of additional weight did not alter sagittal plane kinematics of the knee and ankle joints. CONCLUSIONS: The use of applied weight on the affected limb can reduce unwanted limb flotation on the paretic side during aquatic treadmill walking. It can also assist the stance stability by increasing the stance phase percentage closer to 60% of gait cycle. Both findings can contribute to the development of more efficient motor patterns in gait training for people poststroke. The use of a cuff weight does not seem to reduce the limb circumduction during aquatic treadmill walking.