Hypoxia In Patients Research Articles

Abstract Su601: Missed Hypoxia in the Prehospital Care of Major Traumatic Brain Injury: Discrepancies Between Continuous Monitor Data and Clinical Documentation

Background: It is well established that prehospital hypoxia dramatically increases mortality in Traumatic Brain Injury (TBI). Thus, in EMS TBI research, case ascertainment and risk adjustment are highly dependent upon documentation of in-field O 2 saturation (SpO 2 ). Objective: To compare the rate of hypoxia identified by EMS personnel and documented in EMS patient care records (PCR) versus the actual rate of hypoxia recorded by continuous, non-invasive monitoring in TBI. Methods: A subset of major TBI cases (moderate/severe) from 5 EMS agencies reporting monitor data (Philips MRx™) in the EPIC EMS TBI Study (NIH 1R01NS071049) were evaluated (02/13-02/18). All monitor data available for post-hoc review were displayed and accessible to the providers during EMS care. We compared PCR documentation of hypoxia (SpO 2 <90%) to continuous monitor data in TBI patients (nasal canula O 2 , mask, basic or advanced airway). Statistic: exact McNemar’s test, α=0.05. Results: 120 cases were included [med. age 50; IQR (23.8, 68); 65% male. Monitors recorded 44 hypoxic cases (36.7%; 95%CI 28.1, 45.9%). Only 8 (6.7%; 2.9, 12.7%) were documented in the PCR (p<0.0001; Figure). Three machine-detected hypoxia cases had no PCR-documented SpO 2 at all. Conclusions: The difference in PCR-documented and monitor-identified hypoxia was dramatic. The monitor data revealed a five-fold greater incidence of hypoxia than that documented by EMS providers. This may be partially explained by the continuous nature of pulse oximetry in the face of ongoing care responsibilities and scene distractions. The field environment may cause providers to miss low readings as they fluctuate moment-by-moment. These findings have major clinical implications. While some of the discrepancy between PCR reporting and monitor data might simply be failure to document hypoxia, the much more concerning implication is that many cases might be unrecognized and untreated. Furthermore, these findings have important implications for case ascertainment, confounding, and risk-adjustment in EMS TBI research. Whenever possible, quality improvement and research projects should utilize continuous non-invasive monitor data to identify and evaluate hypoxic patients in the setting of TBI. These findings may also have implications for identifying hypoxia in EMS patients with other critical conditions.

GCN2 kinase activation mediates pulmonary vascular remodeling and pulmonary arterial hypertension.

Pulmonary arterial hypertension (PAH) is characterized by progressive increase of pulmonary vascular resistance and remodeling that result in right heart failure. Recessive mutations of EIF2AK4 gene (encoding general control nonderepressible 2 kinase, GCN2) are linked to heritable pulmonary veno-occlusive disease (PVOD) in patients but rarely in patients with PAH. The role of GCN2 kinase activation in the pathogenesis of PAH remains unclear. Here, we show that GCN2 was hyperphosphorylated and activated in pulmonary vascular endothelial cells (ECs) of hypoxic mice, monocrotaline-treated rats, and patients with idiopathic PAH. Unexpectedly, loss of GCN2 kinase activity in Eif2ak4-/- mice with genetic disruption of the kinase domain induced neither PVOD nor pulmonary hypertension (PH) but inhibited hypoxia-induced PH. RNA-sequencing analysis suggested endothelin-1 (Edn1) as a downstream target of GCN2. GCN2 mediated hypoxia-induced Edn1 expression in human lung ECs via HIF-2α. Restored Edn1 expression in ECs of Eif2ak4-/- mice partially reversed the reduced phenotype of hypoxia-induced PH. Furthermore, GCN2 kinase inhibitor A-92 treatment attenuated PAH in monocrotaline-treated rats. These studies demonstrate that GCN2 kinase activation mediates pulmonary vascular remodeling and PAH at least partially through Edn1. Thus, targeting GCN2 kinase activation is a promising therapeutic strategy for treatment of PAH in patients without EIF2AK4 loss-of-function mutations.

Oxygen therapy practice and associated factors among nurses working at an Ethiopian Referral Hospital

ObjectiveSupplemental oxygen therapy is suppling oxygen at quantities higher than those found in the atmosphere (>21 %) and is mostly prescribed for hypoxic patients. To avoid hypoxemia, hypercapnia, and oxygen poisoning, nurses closely monitor patients receiving oxygen therapy. There are considerable gaps in nurses' practice of oxygen therapy. Patients who receive inappropriate oxygen therapy may have negative effects, and it has financial repercussions for both individuals and nations. The aim of this study was to assess oxygen therapy practices and associated factors influencing oxygen administration among nurses in an Ethiopian Regional Hospital. MethodFrom March 1 to March 30, 2019, a cross-sectional institutional study using quantitative methods was performed amongst nurses working at a referral hospital in northwestern Ethiopia. Data was gathered using structured self-administered questionnaires. ResultIn this study, 147 participants (91.3 %) were found to have inadequate practice with oxygen therapy. Nurses' lack of knowledge about carbon monoxide, adult patients' typical breathing rates, cardiopulmonary function, and devices (face mask, nasal cannula, oxygen concentrators, pulse oximeter and others) that are difficult for patients to accept were found to be factors associated with oxygen administration practice. ConclusionThe findings of this study showed that nurses' use of oxygen administration was subpar. The institutional factors, knowledge gaps, and attitudes of nurses were identified as the determinants affecting oxygen administration practice. Nurses would do better to read up on oxygen administration, interact with one another and undertake further training.

Body mass index is associated with pulmonary gas and blood distribution mismatch in COVID-19 acute respiratory failure. A physiological study.

The effects of obesity on pulmonary gas and blood distribution in patients with acute respiratory failure remain unknown. Dual-energy computed tomography (DECT) is a X-ray-based method used to study regional distribution of gas and blood within the lung. We hypothesized that 1) regional gas/blood mismatch can be quantified by DECT; 2) obesity influences the global and regional distribution of pulmonary gas and blood; 3) regardless of ventilation modality (invasive vs. non-invasive ventilation), patients' body mass index (BMI) has an impact on pulmonary gas/blood mismatch. This single-centre prospective observational study enrolled 118 hypoxic COVID-19 patients (92 male) in need of respiratory support and intensive care who underwent DECT. The cohort was divided into three groups according to BMI: 1. BMI<25kg/m2 (non-obese), 2. BMI = 25-40kg/m2 (overweight to obese), and 3. BMI>40kg/m2 (morbidly obese). Gravitational analysis of Hounsfield unit distribution of gas and blood was derived from DECT and used to calculate regional gas/blood mismatch. A sensitivity analysis was performed to investigate the influence of the chosen ventilatory modality and BMI on gas/blood mismatch and adjust for other possible confounders (i.e., age and sex). 1) Regional pulmonary distribution of gas and blood and their mismatch were quantified using DECT imaging. 2) The BMI>40kg/m2 group had less hyperinflation in the non-dependent regions and more lung collapse in the dependent regions compared to the other BMI groups. In morbidly obese patients, gas and blood were more evenly distributed; therefore, the mismatch was lower than in other patients (30% vs. 36%, p < 0.05). 3) An increase in BMI of 5kg/m2 was associated with a decrease in mismatch of 3.3% (CI: 3.67% to -2.93%, p < 0.05). Neither the ventilatory modality nor age and sex affected the gas/blood mismatch (p > 0.05). 1) In a hypoxic COVID-19 population needing intensive care, pulmonary gas/blood mismatch can be quantified at a global and regional level using DECT. 2) Obesity influences the global and regional distribution of gas and blood within the lung, and BMI>40kg/m2 improves pulmonary gas/blood mismatch. 3) This is true regardless of the ventilatory mode and other possible confounders, i.e., age and sex. Clinicaltrials.gov, identifier NCT04316884, NCT04474249.

Automating Polysomnography in an Under-Explored Animal Model: Preliminary Results from Hibernating Bears

Animal hibernation is a hypometabolic state that may inform translational research to improve clinical outcomes for hypoxic patients whose oxygen supply does not match their demand. Bears are an excellent animal model, as they decrease their body temperature to only 30-35°C during hibernation and suppress their metabolism down to 25% of normal resting levels while having a more comparable physiology to humans than deep hibernators such as small rodents. As little is known about their sleep patterns during hibernation, we continuously monitored for more than 3500 days via biotelemetry a variety of physiological parameters from 16 captive American black bears in and out of hibernation. We recorded EEG, EOG and EMG signals that are commonly used to determine wake, REM sleep and NREM sleep vigilance states in conventional animal models (polysomnography). Such a data set is too large to fully annotate manually, so we compared two automated approaches. We first manually annotated two one-day recordings at body temperature extremes from each of 6 bears during hibernation when body temperatures were oscillating widely in multiday cycles with intermittent bouts of shivering (Tøien et al. 2011). We also manually scored a one-day, non-hibernating recording at normal (summer) body temperature from these bears. Based on this reference data set, we evaluated two automated scoring applications based on different machine learning classifiers: open source Somnotate (author Paul Brodersen), which is trained on multiple files, and proprietary Somnivore (author Giancarlo Allocca), which is trained on a subset of epochs from each individual recording. Somnotate gave best results during hold-one-out testing when using separate models for hibernating and non-hibernating data, and then performed comparably for both conditions. Somnivore was by design trained on a small subset (100 epochs of each kind) of each file to be tested. Both applications provided typical F-measures against manual reference scores in the 0.90-0.97 range. Outliers in the lower 0.72-0.88 range were highly correlated between the two applications, indicating that specific files are more challenging to annotate — either manually, automatically, or both. We conclude that both applications have accuracies on par with manual scorers when trained on high quality data. Supported by NIH COBRE under grant number [P20GM130443]. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Fatty acid-binding protein 5 is a functional biomarker and indicator of ferroptosis in cerebral hypoxia

The progression of human degenerative and hypoxic/ischemic diseases is accompanied by widespread cell death. One death process linking iron-catalyzed reactive species with lipid peroxidation is ferroptosis, which shows hallmarks of both programmed and necrotic death in vitro. While evidence of ferroptosis in neurodegenerative disease is indicated by iron accumulation and involvement of lipids, a stable marker for ferroptosis has not been identified. Its prevalence is thus undetermined in human pathophysiology, impeding recognition of disease areas and clinical investigations with candidate drugs. Here, we identified ferroptosis marker antigens by analyzing surface protein dynamics and discovered a single protein, Fatty Acid-Binding Protein 5 (FABP5), which was stabilized at the cell surface and specifically elevated in ferroptotic cell death. Ectopic expression and lipidomics assays demonstrated that FABP5 drives redistribution of redox-sensitive lipids and ferroptosis sensitivity in a positive-feedback loop, indicating a role as a functional biomarker. Notably, immunodetection of FABP5 in mouse stroke penumbra and in hypoxic postmortem patients was distinctly associated with hypoxically damaged neurons. Retrospective cell death characterized here by the novel ferroptosis biomarker FABP5 thus provides first evidence for a long-hypothesized intrinsic ferroptosis in hypoxia and inaugurates a means for pathological detection of ferroptosis in tissue.

Risk factors for intubation and mortality in patients treated with high flow nasal cannula due to COVID-19 infection. Survival Analysis Study in a Northern Mexican Population.

COVID-19-related acute hypoxic respiratory failure patients often use high-flow nasal cannula (HFNO) oxygen therapy. COVID-19 HFNO intubation and mortality risk factors are understudied in the Mexican population, so the aim was to study them. This retrospective study searched electronic medical records from March 2020 to June 2022 for patients with COVID-19 who required hospitalization and HFNO. Descriptive statistics, a survival curve analysis, and Cox proportional hazard models were used to determine predictor factors for intubation and mortality in patients with HFNO and COVID-19, respectively. A total of 134 patients received HFNO treatment. Ninety-one (67.9%) were men with a mean (SD) age of 54.5 (17.9) years. Common medical history included obesity (n = 89, 66.4%) with a Body Mass Index (BMI) mean (SD) of 31.8 (5.9), hypertension (n = 67, 50.0%), type 2 diabetes (n = 55, 41.0%), and dyslipidemias (n = 43, 32.1%). The variables associated with a greater risk of requiring intubation after high-flow therapy were age (HR = 1.018, 95% CI 1.003-1.034, p = 0.022) and BMI (HR = 1.071, 95% CI 1.024-1.120, p = 0.003). No variables were associated with lower risk. Increased mortality was associated with increasing age (HR = 1.151, 95% CI 1.102-1.201, p = <0.001), hypertension (HR = 4.092, 95% CI 1.369-12.236, p = 0.012), and dyslipidemia (HR = 3.954, 95% CI 1.395-11.209, p = 0.010). Patients with type 2 diabetes had a lower risk of mortality (HR = 0.235, 95% CI 0.080-0.688, p = 0.008). A higher age and BMI were associated with an increased risk of intubation in patients with HFNO and COVID-19. Hypertension and dyslipidemias were associated with a higher risk of mortality.

Rare case of pseudo-pneumoperitoneum as a triad of extensive subcutaneous emphysema and pneumomediastinum as a complication of non-invasive respiratory support

Respiratory support through non-invasive ventilation and high-flow nasal cannula is frequently used in patients with acute respiratory failure as a way to maintain oxygenation without intubation. Although mostly well-tolerated, infrequent but increasingly recognized complications can occur, such as pneumothorax, pneumomediastinum, and subcutaneous emphysema. This likely occurs as a result of alveolar rupture from barotrauma related to ventilatory support and dissection of higher-pressure air along the pulmonary interstitium and into the anatomic cavities of the chest. We present a rare case of pseudo-pneumoperitoneum as a result of non-invasive respiratory support. This occurred as part of a triad of pneumomediastinum and extensive subcutaneous emphysema extending circumferentially around the abdomen and into the scrotum of a hypoxic patient with congestive heart failure and chronic obstructive pulmonary disease exacerbation with pneumonia requiring aggressive respiratory support.

Incidence and Outcome of Spontaneous Alveolar Air Leak Events in COVID-19 Pneumonia: A Prospective Cohort Study

Introduction: Coronavirus Disease 2019 (COVID-19) has increased the burden of hospitalised pneumonia cases and related complications. Spontaneous Pneumothorax (PT) and Pneumomediastinum (PM) have been reported in both spontaneously breathing and ventilated patients with COVID19 pneumonia. Aim: To determine the incidence and outcomes of spontaneous alveolar air leak events in COVID-19 pneumonia. Materials and Methods: This prospective cohort study was carried out from June 2020 to June 2021 at a tertiary care centre in Western India. All incident cases of alveolar air leaks in COVID-19 pneumonia were included. Clinical and demographic data were collected, and statistical analysis was performed. The Chi-square test or Fisher’s exact test were used to assess the differences in subgroup proportions. Results: A total of 79 patients (63 males and 16 females) experienced spontaneous alveolar air leaks in the form of PT, PM (mediastinal emphysema), or Subcutaneous Emphysema (SE), either isolated or in combination. A total of 58 patients (73.41%) had PT, while 8 patients (10.12%) had isolated PM and 2 patients (2.53%) had isolated SE. Of the total events, 35 (44.30%) occurred in spontaneously breathing patients, among them vigorous coughing was an important precipitating factor. At the time of the incident, 1.27%, 21.52%, and 77.21% of the affected cases belonged to mild, moderate, and severe COVID19 categories, respectively. Male patients (n-63, 79.74%) in the age group of 30-60 years were predominantly affected. A total of 38 events (48.10%) occurred within two weeks (early) of symptom onset. The PaO2 :FiO2 ratio at the time of the alveolar leak showed a significant association with the outcome. Patients with PT had a poorer outcome compared to those with other types of alveolar leaks (p-value&lt;0.005). Major bleeding occurred in 2 (3.33%) of the total 60 Intercostal Drainage (ICD) procedures. Prolonged alveolo-pleural fistula healed spontaneously in four out of five cases. The cumulative incidence for air leak events was 1.55%, and for barotrauma, it was 6.47%. The overall mortality in this cohort was 74.68% (n=59), while it was 29.41% (5 out of 17) in the moderate severity group. Patients with lateonset events had a better outcome (p-value&lt;0.005). Conclusion: In this cohort of COVID-19 pneumonia from Western India, the cumulative incidence of spontaneous alveolar air leaks was 1.55%, predominantly affecting males. The early occurrence of PT in severely hypoxic patients on mechanical ventilator was associated with higher mortality.

High-Altitude Hypoxia Is Common in Adults with Sickle Cell Disease

BACKGROUND In Sickle Cell Disease (SCD), hypoxia favors deoxy-HbS formation, sickle hemoglobin (Hb) polymerization, and red blood cell (RBC) sickling. The hypobaric hypoxia of high altitude (such as plane flights and high-altitude vacation destinations) may uncover occult hypoxia in people with SCD, trigger vaso-occlusive episodes, and/or exacerbate cardiopulmonary complications. There are few published data on high-altitude hypoxia in people with SCD. High altitude simulation testing (HAST) recapitulates the hypoxia of high altitude and can be used to assess the need for prophylactic supplemental oxygen prior to trips. At our institution, due to anecdotal reports of symptom exacerbation following air travel, we complete pretravel HAST for people with sickle cell disease, and then prescribe portable oxygen therapy. OBJECTIVE This retrospective cross-sectional study aimed to assess the prevalence of high-altitude hypoxia in those adults with SCD who underwent pretravel evaluation from 2019 to 2023. Additionally, we examined the clinical characteristics of those people found to have high-altitude hypoxia. METHODS After getting IRB approval, we retrospectively reviewed the medical records of patients with SCD who had undergone HAST as part of pretravel evaluation in 2019 through 2023. HAST was performed with the use of a Hans Rudolph two-way non-rebreathing valve system, and oxygen saturation was monitored with a forehead oximeter. Compressed Air (10 liters per minute) and Nitrogen (8 liters per minute) were blended to an oxygen level of 15%, simulating an altitude of 8,000 feet for 20 minutes. High-altitude hypoxia is defined as persistent SpO 2 ≤88% at 15%FiO 2, requiring supplemental oxygen. Demographics, SCD-related medical history, clinical labs and imaging were collected near the time of testing. We assessed the prevalence of high-altitude hypoxia in our patient population over the time period. We described the characteristics of those tested. Using parametric and non-parametric statistical tests, we evaluated associations between time to hypoxia (in minutes). RESULTS 22 adult patients underwent HAST, and 13 (59%) were positive for high-altitude hypoxia (Figure 1). The time to hypoxia ranged from 1-17 minutes with a mean of 5.3 minutes with a minimum SpO 2, in those that tested positive, ranging from 86-89%. However, hypoxic patients were immediately treated with supplemental oxygen during testing, so a true nadir cannot be determined. Compared to those who tested negative, the participants that tested positive had lower BMI and lower mean Hb and hematocrit levels. Their mean absolute reticulocyte counts (ARC) and mean total bilirubin were higher than those who tested negative, and their mean white blood counts (WBC) trended higher. We did not observe significant difference in HAST results by SCD genotype, hydroxyurea use and opioid use. Other patient characteristics are described (Figure 2). We found the strongest inverse correlations between time to hypoxia and WBC (r= -0.73, p= 0.004) and ARC (r= -0.69, p=0.010). CONCLUSIONS Adults with sickle cell disease are at risk for occult hypoxia during travel due to hypobaric hypoxia associated with altitude. In our experience, screening patients with SCD prior to travel, we found HAST-positive hypoxia in 59%, for whom we prescribed supplemental oxygen during travel. Our observations suggested that people with more ‘active’ SCD (lower Hgb and higher ARC) were more likely to have high-altitude hypoxia and tended to declare their hypoxia earlier in the testing period. Our study is limited by sample size, retrospective design, and a lack of patient reported outcomes about altitude associated symptoms or complications. Additionally, there may be a selection bias towards healthier people with SCD, i.e., those who are well enough to travel. However, given the pathophysiology of SCD, our results suggest that providers should be proactive in inquiring about travel plans and assessing the risk for hypoxia. Furthermore, the development of a brief screening tool in this setting may be warranted.

EEG Changes during Propofol Anesthesia Induction in Vegetative State Patients Undergoing Spinal Cord Stimulation Implantation Surgery.

To compare the EEG changes in vegetative state (VS) patients and non-craniotomy, non-vegetative state (NVS) patients during general anesthesia with low-dose propofol and to find whether it affects the arousal rate of VS patients. Seven vegetative state patients (VS group: five with traumatic brain injury, two with ischemic-hypoxic VS) and five non-craniotomy, non-vegetative state patients (NVS group) treated in the Department of Neurosurgery, Peking University International Hospital from January to May 2022 were selected. All patients were induced with 0.5 mg/kg propofol, and the Bispectral Index (BIS) changes within 5 min after administration were observed. Raw EEG signals and perioperative EEG signals were collected and analyzed using EEGLAB in the MATLAB software environment, time-frequency spectrums were calculated, and EEG changes were analyzed using power spectrums. There was no significant difference in the general data before surgery between the two groups (p > 0.05); the BIS reduction in the VS group was significantly greater than that in the NVS group at 1 min, 2 min, 3 min, 4 min, and 5 min after 0.5 mg/kg propofol induction (p < 0.05). Time-frequency spectrum analysis showed the following: prominent α band energy around 10 Hz and decreased high-frequency energy in the NVS group, decreased high-frequency energy and main energy concentrated below 10 Hz in traumatic brain injury VS patients, higher energy in the 10-20 Hz band in ischemic-hypoxic VS patients. The power spectrum showed that the brain electrical energy of the NVS group was weakened R5 min after anesthesia induction compared with 5 min before induction, mainly concentrated in the small wave peak after 10 Hz, i.e., the α band peak; the energy of traumatic brain injury VS patients was weakened after anesthesia induction, but no α band peak appeared; and in ischemic-hypoxic VS patients, there was no significant change in low-frequency energy after anesthesia induction, high-frequency energy was significantly weakened, and a clear α band peak appeared slightly after 10 Hz. Three months after the operation, follow-up visits were made to the VS group patients who had undergone SCS surgery. One patient with traumatic brain injury VS was diagnosed with MCS-, one patient with ischemic-hypoxic VS had increased their CRS-R score by 1 point, and the remaining five patients had no change in their CRS scores. Low doses of propofol cause great differences in the EEG of different types of VS patients, which may be the unique response of damaged nerve cell residual function to propofol, and these weak responses may also be the basis of brain recovery.

Inhibition of bradykinin in SARS-CoV-2 infection: a randomised, double-blind trial of icatibant compared with placebo (ICASARS)

SARS-CoV-2 binds to ACE2 receptors and enters cells. The symptoms are cough, breathlessness, loss of taste/smell and X-ray evidence of infiltrates on chest imaging initially caused by oedema, and subsequently...

SAT539 Thyroid Cancer Presenting as Aspiration Pneumonia

Abstract Disclosure: S. Aslam: None. M. Asif: None. I. Nadeem: None. W.J. Khan: None. Background Goiter, most often, is first noticed as a visible neck mass; however, some patients may present with signs and symptoms of hypothyroidism, or hyperthyroidism. Retrosternal extension can cause compression of the trachea, esophagus, and jugular veins resulting in dysfunction of these viscera. CaseA 68-year-old male presented with SOB, and weakness for 5 days. He had SaO2 79% on room air requiring oxygen, RR 28/min, HR 78/min and Temp.101.6 F, BP 94/48 mmHg. The lung exam revealed bilateral rhonchi and coarse crypts. Minimal non-tender nodularity was noted on the thyroid palpation not previously noticed by the patient or his family. Chest x-ray showed bilateral airspace opacities. CT chest revealed a large upper mediastinal mass displacing the trachea and esophagus to the right, a nodule in the left lobe of thyroid, subcarinal and right hilar lymphadenopathy and bilateral dependent consolidative opacities suggesting aspiration pneumonia but no PE. A barium esophagogram showed a 7.5 cm mediastinal mass causing 50% narrowing and displacement of esophagus and compression with left sided deviation of trachea. A barium swallow study was done, and the patient was found to have aspiration with all administered food types due to an abnormal swallowing mechanism. The patient was advised NPO and placed on NG tube feeding to prevent further aspiration. The patient underwent bronchoscopy and EBUS from station 4 lymph node, the pathology of which did not show any malignant cells. However, due to high clinical suspicion of a malignant process, the patient underwent a CT-guided biopsy of the mediastinal mass that showed bland thyroid tissue. Ultrasound of thyroid revealed multiple right and left lobe nodules. TSH and free T4, and calcitonin were WNL. The patient's hypoxia and fever resolved after completion of the antibiotics including ceftriaxone and doxycycline and being nothing per oral within 7 days. Due to persistent dysphagia, he was placed on PEG tube feeding and discharged from the hospital to a nursing home. The patient underwent ultrasound-guided fine needle biopsy of 1 right-sided and 2 left-sided thyroid nodules that resulted as papillary thyroid cancer. He underwent a successful right-sided thoracotomy and removal of large sized thyroid mass. The patient is seeing endocrinology as an outpatient for radioactive iodine and hormone replacement therapy. Conclusion We treated a patient of follicular carcinoma who presented with extrathyroidal symptoms. Retrosternal or ectopic thyroid tumors can present as euthyroid state without obvious enlargement of the normal thyroid gland. A meticulous clinical evaluation should include the differential diagnosis of retrosternal goiter or ectopic thyroid with cancer when treating patients who preset with sign and symptoms concerning for mediastinal disease. Presentation Date: Saturday, June 17, 2023

Right heart echocardiography findings in hypoxic pneumonia patients during the COVID-19 pandemic in a South African population.

The right ventricle is affected by Coronavirus disease 19 (COVID-19) via multiple mechanisms, which can result in right ventricular dysfunction (RVD). This study aimed to provide an assessment of right heart function using conventional echocardiography and advanced strain imaging, in patients with hypoxic pneumonia during the COVID-19 pandemic. This study was an observational, prospective, single-centre study, including adults with hypoxic pneumonia, in two groups: COVID-19 pneumonia; and non-COVID-19 pneumonia. Bedside echocardiography was performed according to a pre-specified protocol and all right heart measurements were done as per standard guidelines. Right ventricular free wall strain (RVFWS) was measured using Philips® QLAB 11.0 speckle tracking software. Descriptive and comparative statistics were used to analyse data. Spearman Rank Order Correlations were used to determine the correlation between right ventricular (RV) parameters and clinical parameters. Univariate and multivariate logistic regression analyses were performed to characterize the predictors of in-hospital mortality. We enrolled 48 patients with COVID-19 pneumonia and 24 with non-COVID-19 pneumonia. COVID-19 patients were significantly older with a higher frequency of hypertension and diabetes and a trend towards a lower severity of illness score. Mean RVFWS yielded the highest estimates for the prevalence of RVD (81%), with no difference between the two pneumonia groups. Median Tricuspid Annular Plane Systolic Excursion (TAPSE) and right ventricular systolic excursion velocity (RVS') were not significantly different between COVID-19 (TAPSE 17.2 and RVS' 12), and non-COVID-19 pneumonia (TAPSE 17.8 and RVS' 12.1) with P values of 0.29 and 0.86, respectively. Non-COVID-19 pneumonia patients with moderate to severe hypoxaemia (PF < 150) were at greater risk of an elevated RV Systolic Pressure >30 mmHg respiratory rate = 3.25 (CI 1.35-7.82) on admission. Troponin levels discriminated between COVID-19 survivors (6 ng/L) and non-survivors (13 ng/L), P = 0.04. The mortality rate for COVID-19 was high (27%) compared to non-COVID-19 pneumonia (12%). Patients with COVID-19 pneumonia had a similar admission prevalence of RVD when compared to patients with non-COVID-19 pneumonia. Despite preserved traditional parameters of RV systolic function, RVFWS was diminished in both groups, and we propose that RVFWS serves as an important marker of the subclinical disease of RV.

Facilitated Intubation: Time to Re-examine an Old Technique With Its Associated Risks Mitigated by New Technology.

Facilitated intubation (FI) refers to intubation performed using a sedative or anesthetic drug as an induction agent, without the use of a paralytic (neuromuscular blocking agent). In comparison, rapid sequence intubation (RSI) employs both an induction agent and a paralytic drug. RSI has been seen to outperform FI in terms of first-pass success when performing direct laryngoscopy and was quickly adopted as the gold standard in all situations. Recently, ketamine-only intubation has been used in situations where there is distorted anatomy or apnea intolerance (physically and physiologically difficult airways) resulting in an increased risk of a can't intubate/can't oxygenate scenario or significant hypoxemia. Frequent and recurring national ketamine shortages have resulted in renewed interest in whether or not other forms of FI are feasible in an era where other factors that mitigate complictions in achieving first-pass success (video laryngoscopy, bougie use, semi-Fowler positioning) are commonly used. We present a case series with outcomes for profoundly hypoxic patients with coronavirus disease 2019 (COVID-19) (physiologically difficult airways) undergoing FI during a time of national ketamine shortage, using modern techniques and technology to maximize first-pass success and minimize peri-intubation complication. We included patients with COVID-19 pneumonia with pre-intubation oxygen saturations of less than 80% (significant hypoxemia) requiring intubation who presented to a tertiary care center in southern United States between August 25, 2021, and October 22, 2021.In this specific cohort, patients underwent endotracheal intubation with midazolam for induction without the use of paralytic agents.We used video-assisted laryngoscopy to increase the success of the first-pass attempt as well as placing the patients in a semi-Fowler position (head of bed elevation 30-45°) and bilevel positive pressure pre-oxygenation to minimize peri-intubation complications. Our case series included 29 consecutive patients that met the inclusion criteria.The mean ± standard deviation (SD) age of the patients was 49.5±15.0 years. The mean±SD pre-intubation oxygenation of our cohort was 73.1±5.9%.All 29 intubations were successful on the first-pass attempt.Only one patient (3.4%) required a rescue paralytic to facilitate oral opening. Of note, 27/29 (93%) of the patients did not receive any immunizations (including partial) for COVID-19.There were no incidents of peri-intubation arrest (cardiac arrest within 30 minutes of induction) or aspiration. In 29 physiologically difficult patients with acute respiratory failure, in whom the physician determined that RSI posed a higher than normal risk, FI assisted by VL, semi-Fowler positioning, and bilevel positive pressure pre-oxygenation resulted in excellent successful first-pass intubation rates without any incidencesof peri-intubation arrestor aspiration.While this cohort was small, our study reveals that FI with midazolam does not likely pose a higher risk than ketamine-only intubationand warrants further study.

Predictors of pulmonary embolism in hospitalized patients with COVID-19

BackgroundHigh venous thromboembolism (VTE) rates have been described in critically ill patients with COVID-19. We hypothesized that specific clinical characteristics may help differentiate hypoxic COVID-19 patients with and without a diagnosed pulmonary embolism (PE).MethodsWe performed a retrospective observational case-control study of 158 consecutive patients hospitalized in one of four Mount Sinai Hospitals with COVID-19 between March 1 and May 8, 2020, who received a Chest CT Pulmonary Angiogram (CTA) to diagnose a PE. We analyzed demographic, clinical, laboratory, radiological, treatment characteristics, and outcomes in COVID-19 patients with and without PE.Results92 patients were negative (CTA-), and 66 patients were positive for PE (CTA+). CTA + had a longer time from symptom onset to admission (7 days vs. 4 days, p = 0.05), higher admission biomarkers, notably D-dimer (6.87 vs. 1.59, p < 0.0001), troponin (0.015 vs. 0.01, p = 0.01), and peak D-dimer (9.26 vs. 3.8, p = 0.0008). Predictors of PE included time from symptom onset to admission (OR = 1.11, 95% CI 1.03–1.20, p = 0.008), and PESI score at the time of CTA (OR = 1.02, 95% CI 1.01–1.04, p = 0.008). Predictors of mortality included age (HR 1.13, 95% CI 1.04–1.22, p = 0.006), chronic anticoagulation (13.81, 95% CI 1.24–154, p = 0.03), and admission ferritin (1.001, 95% CI 1-1.001, p = 0.01).ConclusionsIn 158 hospitalized COVID-19 patients with respiratory failure evaluated for suspected PE, 40.8% patients had a positive CTA. We identified clinical predictors of PE and mortality from PE, which may help with early identification and reduction of PE-related mortality in patients with COVID-19.

The hypoxic patient in the intensive cardiac care unit: from nasal cannulas to oro-tracheal intubation

Acute respiratory failure is a frequent complication of patients admitted to the intensive cardiac care unit and it is associated with a poor short- and long-term outcome. Acute respiratory failure can be managed with traditional oxygen therapy, with high-flow nasal cannula, continuous positive airway pressure, non-invasive ventilation or invasive ventilation according to clinical and blood gas condition. The use of advanced respiratory therapies is associated with both respiratory and hemodynamic effects, therefore the intensivist cardiologist should know deeply these respiratory devices. The intensivist cardiologist should perform an early diagnosis of acute respiratory failure, an appropriate selection of the respiratory device, and accurate monitoring and management to obtain clinical improvement and to avoid mechanical invasive ventilation.

New application of saline contrast-enhanced electrical impedance tomography method for right ventriculography besides lung perfusion: detection of right-to-left intracardiac shunt.

Saline contrast-enhanced electrical impedance tomography (EIT) has been used to identify the respiratory failure etiologies through assessment of regional lung perfusion at the bedside. In this study, we introduce a novel approach to detect right-to-left intracardiac shunt based on the center of heart (CoH) parameter determined from the early phase of impedance-time curve after saline bolus injection. The timepoints when the saline bolus enter the heart (T0) and the lung regions (T1) are identified at first. A moving time window from T0 to T1 is then generated with steps of 0.5 s and the slope of the impedance-time curve in each pixel within the window calculated. CoH is calculated as the geometric center of pixel slope values in the right-to-left image direction. To illustrate how this method works in practice, we calculated the CoH values at T0 to T1 in 10 control hypoxic patients with no right-to-left shunt. In addition, we examined two critically ill patients with right-to-left intracardiac shunt. One was postcardiac surgery patient who had a residual atrial septal defect by color doppler of transesophageal echocardiograph. The other patient had a congenital heart disease of ventricular septal defect by color doppler of trans-thoracic echocardiography. A large difference in CoH between T0 to T1 was observed in the two patients with intracardiac shunt than in the control patients (11.06 ± 3.17% vs. 1.99 ± 1.43%, P = 0.030). Saline bolus EIT for lung perfusion might be used as ventriculography to identify the right-to-left intracardiac shunt at the bedside.

A technique to measure tidal volume during noninvasive respiratory support by continuous-flow helmet CPAP

PurposeThe coronavirus disease 2019 (COVID-19) pandemic has promoted the use of helmet continuous positive airway pressure (CPAP) for noninvasive respiratory support in hypoxic respiratory failure patients, despite the lack of tidal volume monitoring. We evaluated a novel technique designed to measure tidal volume during noninvasive continuous-flow helmet CPAP.MethodsA bench model of spontaneously breathing patients undergoing helmet CPAP therapy (three positive end-expiratory pressure [PEEP] levels) at different levels of respiratory distress was used to compare measured and reference tidal volumes. Tidal volume measurement by the novel technique was based on helmet outflow-trace analysis. Helmet inflow was increased from 60 to 75 and 90 L/min to match the patient’s peak inspiratory flow; an additional subset of tests was conducted under the condition of purposely insufficient inflow (i.e., high respiratory distress and 60 L/min inflow).ResultsThe tidal volumes examined herein ranged from 250 to 910 mL. The Bland‒Altman analysis showed a bias of -3.2 ± 29.3 mL for measured tidal volumes compared to the reference, corresponding to an average relative error of -1 ± 4.4%. Tidal volume underestimation correlated with respiratory rate (rho = .411, p = .004) but not with peak inspiratory flow, distress, or PEEP. When the helmet inflow was maintained purposely low, tidal volume underestimation occurred (bias − 93.3 ± 83.9 mL), corresponding to an error of -14.8 ± 6.3%.ConclusionTidal volume measurement is feasible and accurate during bench continuous-flow helmet CPAP therapy by the analysis of the outflow signal, provided that helmet inflow is adequate to match the patient’s inspiratory efforts. Insufficient inflow resulted in tidal volume underestimation. In vivo data are needed to confirm these findings.

Emergency Medical Services Management of Bronchospasm in the United States: A Cross-Sectional Analysis and Nationwide Quality Assessment

Background/Objective: Bronchospasm, caused by asthma and other related conditions, is a significant cause of morbidity and mortality commonly managed by emergency medical services (EMS). We aimed to evaluate the quality of prehospital management of bronchospasm by EMS in the US. Methods: The National EMS Information System Public Release Research dataset, a nationwide convenience sample of prehospital patient care report data from 2018 to 2019, was used to capture 9-1-1 activations where patients aged ≥2 years were treated and transported by EMS for suspected bronchospasm. First, we described the extent to which EMS care met eight quality measures identified from available statewide EMS protocols, existing quality measures, and national guidelines. Second, we quantified the extent of risk-standardized agency-level variation in administration of inhaled beta agonists and systemic corticosteroids using logistic regression models, accounting for patient characteristics, severity, and clustering by agencies. Third, we compared rates of completed prehospital interventions between pediatric (age <18 years) versus adult patients using two-sample t-tests. Results: A total of 1,336,988 EMS encounters for suspected bronchospasm met inclusion criteria. Median age of patients was 66 years, with only 4% pediatric; 55% were female. Advanced life support (ALS) units managed 94% of suspected bronchospasm. Respiratory rate (98%) and pulse oximetry (96%) were documented in nearly all cases. Supplemental oxygen was administered to hypoxic patients by 65% of basic life support (BLS) and 73% of ALS units. BLS administered inhaled beta-agonist therapy less than half the time (48%), compared to 77% by ALS. ALS administered inhaled anticholinergic therapy in 38% of cases, and systemic corticosteroids in 19% of cases. Pediatric patients were significantly less likely to receive supplemental oxygen when hypoxic, inhaled beta-agonists, inhaled anticholinergics, or systemic corticosteroids. Conclusions: We found important gaps in recent EMS practice for prehospital care of suspected bronchospasm. We highlight three targets for improvement: inhaled beta-agonist administration by BLS, systemic corticosteroid administration by ALS, and increased interventions for pediatric patients. These findings indicate important areas for research, protocol modification, and quality improvement efforts to improve EMS management of bronchospasm.