Hypoxemia Research Articles

Platypnea-orthodeoxia syndrome (POS) is a rare condition of positional dyspnea with hypoxemia that can pose a diagnostic challenge to clinicians. We report two cases of POS with different pathophysiologic triggers and similar clinical features. In our report, both patients manifested a severe hypoxemia with low response to increase of fractional inspired oxygen, unremarkable physical examination of the lungs, and no radiological findings of the pulmonary embolism. In both cases, an interatrial communication was found in association with a right-to-left interatrial shunting. Recognition of POS is crucial because symptoms can be quickly relieved by recumbency, unlike other types of hypoxemia. This simple solution may prevent the use of sedative therapy, invasive ventilatory support, and vasopressor agents, which could even exacerbate the right-to-left extrapulmonary shunt and worsen clinical conditions.

Cytomegalovirus (CMV) is the most common congenital viral infection in neonates. Postnatal infection regarding infants rarely has significant clinical consequences. However, preterm may be at higher risk of developing symptomatic postnatal CMV disease. A multipara woman delivered vaginally a male preterm infant at 30 weeks' gestation who was suspected of early-onset sepsis in view of chronic leaking. The baby developed severe hypoxemia, and persistent pulmonary hypertension after delivery, with progressive deterioration and minimal effect of advanced ventilation, antibiotics, and pulmonary vasodilators. Sepsis screen and cultures for bacteria and fungi were negative. The baby was having enlarged liver and spleen which was noticed on day 15 of life. TORCH titer of the baby revealed CMV IgM and subsequently, CMV was isolated in the urine and in the blood plasma by polymerase chain reaction. Oral valganciclovir improved hematological parameters of the baby and respiratory support could be weaned. CMV being the most common intrauterine infection should be considered in differential diagnosis in unusual presentation of suspected sepsis and oral valganciclovir can be considered as good option for treatment.

Gestational hypoxemia is often associated with reduced birth weight, yet how hypoxemia controls uteroplacental nutrient metabolism and supply to the fetus is unclear. This study tested the effects of maternal hypoxemia (HOX) between 0.8 and 0.9 gestation on uteroplacental nutrient metabolism and flux to the fetus in pregnant sheep. Despite hypoxemia, uteroplacental and fetal oxygen utilization and net glucose and lactate uptake rates were similar in HOX (n = 11) compared to CON (n = 7) groups. HOX fetuses had increased lactate and pyruvate concentrations and increased net pyruvate output to the utero‐placenta. In the HOX group, uteroplacental flux of alanine to the fetus was decreased, as was glutamate flux from the fetus. HOX fetuses had increased alanine and decreased aspartate, serine, and glutamate concentrations. In HOX placental tissue, we identified hypoxic responses that should increase mitochondrial efficiency (decreased SDHB, increased COX4I2) and increase lactate production from pyruvate (increased LDHA protein and LDH activity, decreased LDHB and MPC2), both resembling metabolic reprogramming, but with evidence for decreased (PFK1, PKM2), rather than increased, glycolysis and AMPK phosphorylation. This supports a fetal‐uteroplacental shuttle during sustained hypoxemia whereby uteroplacental tissues produce lactate as fuel for the fetus using pyruvate released from the fetus, rather than pyruvate produced from glucose in the placenta, given the absence of increased uteroplacental glucose uptake and glycolytic gene activation. Together, these results provide new mechanisms for how hypoxemia, independent of AMPK activation, regulates uteroplacental metabolism and nutrient allocation to the fetus, which allow the fetus to defend its oxidative metabolism and growth.

The syndrome of combined emphysema of the upper lobes and fibrosis of the lower lobes on chest computed tomography results in a characteristic functional profile, with preserved lung volumes, hypoxemia at exercise. Despite subnormal spirometry, combined pulmonary fibrosis and emphysema is a severe entity. The presence of pulmonary arterial hypertension at diagnosis is a critical determinant of prognosis.

Acute aortic dissection is a catastrophic event with high mortality rate if left untreated. Complications of aortic dissection are fairly common, and some of them increase mortality rates further, necessitating early diagnosis and treatment. We present a case of Stanford type A aortic dissection with an uncommon complication of right ventricular failure, which resulted in a rare presentation of persistent hypoxemia despite intubation and maximal ventilatory support. Other common causes of hypoxemia were ruled out and this was eventually attributed to the aortic dissection and emergency surgery was arranged for the patient. Our case can help to increase the awareness of such a potential association, which should be considered in future similar clinical situations, thus minimizing any delay in management. J Med Cases. 2021;12(4):145-148 doi: https://doi.org/10.14740/jmc3652

Sevoflurane Sedation Protocol in Children with Cerebral Palsy Undergoing BotulinumToxin-A Injections - DATABASE

Background Chronic obstructive pulmonary disease (COPD) is a common, preventable, and treatable disease characterized by persistent respiratory symptoms and airflow limitation that is due to airway and/or alveolar abnormalities, usually caused by significant exposure to noxious particles or gases. The chronic airflow limitation that characterizes COPD is caused by a mixture of small airway disease (e.g. obstructive bronchiolitis) and parenchymal destruction (emphysema), the relative contributions of which vary from person to person. Aim The aim of the study was to determine the effect of systemic corticosteroids in patients with severe acute exacerbations of COPD admitted to the ICU receiving ventilatory support. Patients and methods A total of 100 patients with acute exacerbations of COPD leading to hypoxemia and respiratory acidosis with pH less than 7.35 and PaCO2 more than 45 mmHg admitted to the ICU who were receiving ventilator support (invasive or noninvasive mechanical ventilation) were included. Results It was noticed that steroid group had significantly lower duration of mechanical ventilation (4.67±2.76 vs. 2.76±1.11 days; P=0.01), ICU stay (5.33±2.87 vs. 7.89±3.36 days; P=0.04), and hospital stay (11.65±3.89 vs. 16.67±4.44 days; P=0.03). Conclusion Corticosteroid therapy was associated with significantly lower duration of mechanical ventilation, ICU stay, and hospital stay.

DeGrado, Jeremy1; Szumita, Paul2; Schuler, Brian2; Dube, Kevin1; Lenox, Jesslyn3; Kim, Edy4; Weinhouse, Gerald5; Massaro, Anthony6 Author Information

INTRODUCTION: Although initially compared to ARDS, COVID-19 pneumonitis presents with unique features, suggesting tailored approaches may be required Gattinoni et al recently described two distinct phenotypes of COVID-19, L-type and H-type, with low or high elastance, V/Q ratio, lung weight, and recruitability, respectively METHODS: 76 F with lymphoma presented with worsening cough and fever and tested positive for COVID-19 She was saturating 93% on room air with no increased work of breathing (SpO2/FiO2 442), suggesting L-phenotype CT chest showed multifocal groundglass opacities On day 3, she developed worsening hypoxemia (SpO2/FiO2 158 3) Despite a significant drop in SpO2/FiO2 ratio, she denied subjective dyspnea and had no increased work of breathing, continuing to demonstrate L-phenotype The patient requested to avoid invasive mechanical ventilation and a timed trial of HFNC was agreed upon She received therapies as per institutional protocol, which included remdesivir, convalescent plasma, steroids, aspirin once daily, enoxaparin 40 mg twice daily, and three doses of tocilizumab Despite receiving all this, she continued to worsen, requiring 100% FiO2 HFNC A 7-day course of anakinra was started The patient continued to remain an L-phenotype with no increased work of breathing Following the first dose of anakinra, FiO2 requirements decreased significantly from 100 to 70%, and over the course of 2 weeks, she weaned to 2L NC, making a complete clinical recovery and was discharged to a long-term acute care facility for further rehabilitation RESULTS: The difference in pulmonary presentation and treatment of COVID-19 remains undetermined Our patient had severe hypoxemia with no increased work of breathing, consistent with L-phenotype Due to a high provider to patient ratio at our institution, we were able to provide a prolonged time limited trial of HFNC and avoid invasive mechanical ventilation We found the patient's respiratory status dramatically improved following anakinra The treatment of select COVID-19 patients with HFNC and anakinra may avoid invasive mechanical ventilation, preventing ventilator complications and conserving resources

Vazquez-Colon, Zasha Francheska1; Ezmigna, Dima1; Schlurmann, Natalia Martinez1 Author Information

Spontaneous pneumomediastinum is a rare entity in pediatric age, with multifactorial etiology. A 16-year-old male with multiple allergies (mites, dogs, cats, and grasses), daily smoker (one pack/day for one year), and regular cannabis, cocaine, and amphetamine consumer went to the Emergency Department of the local hospital with cough, dyspnea, chest pain, and fever with 12 hours of evolution. On physical examination, the boy presented facies complaints, polypnea, shortness of breath, extensive subcutaneous emphysema in the cervical region and right hemithorax, and diminished vesicular murmur bilaterally with expiratory wheezing. Chest x-ray was performed, revealing alterations compatible with pneumomediastinum and subcutaneous emphysema in the cervical region. Urine test was positive for tetrahydrocannabinoids. Atopy (IgE levels) study was performed, with positive result, and serological testing was performed for Mycoplasma pneumoniae, showing IgM of 33U/mL and IgG of 25U/mL.In this clinical case, multiple pneumomediastinum triggering/predisposing factors can be identified, including marked smoking habits, acute mycoplasma infection, and inhaled and smoked drug consumption. The aim of this study was to review the pathophysiology/semiology of pneumomediastinum and emphasize the importance of clinical suspicion.

Introdução: as cirurgias cardíacas são descritas como intervenções complexas exigem tratamento adequado em todas fases operatórias. Objetivo geral: realizar uma revisão da literatura para investigar a conduta do profissional de enfermagem no pós-operatório imediato no transplante cardíaco. Metodologia: para o desenvolvimento deste estudo foi realizada uma revisão da sistemática a com uma abordagem qualitativa, optando-se apenas por publicações com menos de 5 anos indexadas nas revistas na área de saúde. Resultado: as principais complicações mais comuns que os pacientes em pós-operatório por transplante cardíaco podem enfrentar em seu tempo de internação são, dor, dificuldade na troca de gases, débito cardíaco diminuído e risco para desequilíbrio de volume de líquido, arritmia cardíaca, instabilidade hemodinâmica e hipotermia. As apresentações pulmonares podem ser atelectasias, pneumonias, episódio de hipoxemia e a síndrome da angústia respiratória aguda. Portanto, o enfermeiro é extremamente importante, pois o profissional atua na avaliação hemodinâmica, avaliação da função renal e balanço hídrico; prevenção de infecções; detecção e tratamento de rejeição e garantir o suprimento adequado de nutrientes, além de fornecer recursos humanos e materiais. Sendo responsável por cuidar, controlar e observar o paciente, levando em consideração a complexidade da cirurgia.

Some patients with COVID-19 and acute respiratory distress syndrome (ARDS) develop refractory hypoxemia that warrants consideration of extracorporeal

INTRODUCTION Hydrocarbon ingestions in pediatrics are rare, but have high risk of morbidity and mortality due to respiratory failure. Hypoxemia following hydrocarbon ingestions is most commonly associated with aspiration pneumonitis. We describe a patient who ingested a hydrocarbon-containing glue accelerator and was found to have methemoglobinemia as the primary cause of her hypoxemia. CASE REPORT A 21-month-old healthy girl was discovered playing with model airplanes with an open bottle of “Insta Set” glue accelerator in her hands, and residual glue on her shirt, followed by emesis of sticky …

Case Report: A 15 week old preterm male born at 27 weeks gestational age presented with persistent respiratory failure requiring mechanical ventilation with high FiO2 (60%) requirement. His birth history was significant for respiratory failure in the delivery room requiring surfactant, intubation, and mechanical ventilation. At 7 weeks of life, an echocardiogram showed mild to moderate pulmonary hypertension (PH) requiring sildenafil. His respiratory failure (capillary PCO2 58 mm Hg) and hypoxemia persisted despite mechanical ventilation, diuretics, bronchodilators, and systemic corticosteroids. A chest radiograph showed increased pulmonary interstitial markings with scattered patchy opacities consistent with bronchopulmonary …

Hypoxemia out of proportion to respiratory effort — “silent hypoxemia” — has been reported in patients with COVID-19. Given our lack of understanding

In pandemic times, medical staff is becoming a key resource in fighting the infection. To achieve the best medical care, relevant techniques and procedures have to be taught to medical staff to reduce the risk of infection. COVID patients often need mechanical ventilation due to progredient respiratory insufficiency, so an endotracheal intubation becomes a critical procedure in managing these patients. This procedure has an increased risk of infection due to aerosol formation and working with an unsecured airway. Patient safety should not be neglected, and complications like hypoxaemia and aspiration should be avoided. At the same time, personal protection from infection is of utmost importance becuase human resources in a pandemic crisis must be preserved. This video shows the procedure of endotracheal intubation while taking personal infection protection into account.

Patients with severe COVID-19 often present with profound hypoxemia. Initial recommendations for their management included early intubation, but this

Objective To investigate the incidence of hypoxemia in the anesthesia recovery period after thoracoscopic surgery and explore the risk factors of hypoxemia and its predictive efficiency. Methods A total of 841 patients, aged 18-90 years, American Society of Anesthesiologists (ASA) physical status of Ⅰ‒Ⅲ , who were scheduled for thoracoscopic surgery from October 2017 to May 2019 in the Second Affiliated Hospital of Zhejiang University School of Medicine, were retrospectively analyzed in the current study. They were divided into a hypoxemia group and a non-hypoxemia group, according to the presence of hypoxemia in the anesthesia recovery period. Both groups were compared for their clinical data before and during surgery to evaluate the condition of hypoxemia in the recovery period. Their risk factors were analyzed by multivariate Logistic regression. A receiver operating characteristic (ROC) curve was established to examine its predictive efficiency towards hypoxemia. Results Among the 841 patients, 239 patients (28.4%) presented hypoxemia during the anesthesia recovery period. The risk factors of hypoxemia included age [odds ratio (OR)=1.028, 95% confidence interval (CI) 1.006-1.050], body mass index (BMI) (OR=1.217, 95%CI 1.111-1.333), hypertension (OR=2.462, 95%CI 1.564-3.875), mediastinal surgery (OR=2.756, 95%CI 1.605-6.873) and supine position (OR=2.230, 95%CI 0.936-5.314). For hypoxemia in the anesthesia recovery period, its area under the receiver operating characteristic curve (AUC) was 0.723 (95%CI=0.685-0.761, P<0.01), with a sensitivity of 63.6% and a specificity of 69.4%. Conclusions Extensive attention towards blood pressure control and body weight management before surgery, and comprehensive understanding the mechanism of hypoxemia caused by surgery at the supine position and active prevention, may reduce the incidence of hypoxemia during the anesthesia recovery period after thoracoscopic surgery. Key words: Thoracoscopy; Anesthesia recovery period; Hypoxemia; Risk factor

Objective To compare the application of cuffed and uncuffed endotracheal tubes in full-term neonates undergoing congenital intestinal atresia surgery. Methods Sixty newborns who were scheduled to perform congenital intestinal atresia surgery under general anesthesia were selected. They were divided into two groups, according to the random number table method (n= 30): a cuffed endotracheal tube group (group C) and an uncuffed endotracheal tube group (group U). Group C used cuffed endotracheal tubes for surgical procedures, while uncuffed endotracheal tubes were adopted in group U. Both groups were compared for the changing rate of endotracheal tubes and airway condition after surgery [the incidence of hypoxemia within 5 min after extubation (SpO2<95%), laryngospasm and post-operative wheezing], and the incidence of inspiratory pneumonia during follow-up visit one week after surgery. Results Patients in group U presented increases in the changing rate of endotracheal tubes (26.7% vs 3.3%), the incidence of hypoxemia within 5 min after extubation (10.0% vs 0), laryngospasm incidence (10.0% vs 0) and inspiratory pneumonia incidence (10.0% vs 0), compared with those in group C (P 0.05). Conclusions Cuffed endotracheal tubes are superior to uncuffed ones in full-term neonates during congenital intestinal atresia surgery, with good efficacy. Key words: Neonate; Endotracheal tube; Anesthesia, general; Congenital intestinal atresia