Blood Oxygen Saturation Values Research Articles

COVID-19-associated morbidity and mortality outcomes in pregnant patients admitted to intensive care unit

Background: Our study aimed to evaluate the clinical characteristics and maternal-fetal outcomes of pregnant women admitted to the ICU due to COVID-19 pneumonia. Materials and Methods: Demographic data, presenting complaints, laboratory values, pregnancy outcomes, delivery method, and ICU mortality were recorded. Results: A total of 10 pregnant patients were admitted to the intensive care unit of our hospital due to SARS-COV-2 infection during the 2-year period. Arterial blood oxygen saturation values measured at admission to the ICU were higher in the surviving patients. Six of the 10 patients died. Only one of the 7 patients requiring invasive mechanical ventilation survived. Conclusions: We found that COVID-19-infected pregnant women with severe symptoms have several maternal morbidities and poor obstetric outcomes, such as prolonged intensive care unit stay, increased mortality, neonatal deaths, and caserean section.

Effects of progressive muscle relaxation exercises on the vital signs and fatigue in kidney transplant patients: a randomized controlled trial.

Multiple effective nursing interventions are needed to manage deviations from normal vital signs and fatigue experienced by kidney transplant patients. In this study, we investigated the effect of progressive muscle relaxation (PMR) exercises on vital signs and fatigue in kidney transplant patients. We conducted a randomized controlled experimental study with 52 patients (intervention = 26, control = 26) who underwent kidney transplantation at a university hospital in Turkey and met the inclusion criteria. The "Descriptive Characteristics Form", "Vital Signs Monitoring Form", and "Fatigue Severity Scale" were used to record data on the patients. Then, the patients in the intervention group (baseline assessment) were trained to perform PMR exercises, asked to practice, and followed up (first follow-up). Patients were recommended to perform PMR exercises for 20min every day for four weeks. The second follow-up in the second week after discharge and the third follow-up at the end of the fourth week were performed in the outpatient clinic. We found that the pulse rate, body temperature, and arterial blood pressure decreased over time and oxygen saturation increased in the patients of the intervention group. The PMR exercises decreased fatigue in these patients. The arterial blood pressure and oxygen saturation values differed significantly across different time points among the patients in the control group. The difference in the scores of fatigue severity between the pre-follow-up and the third follow-up in the control group was not significant. PMR exercises were found to be an effective nursing intervention in regulating vital signs and reducing fatigue in renal transplant patients.

Machine-learning-based mapping of blood oxygen saturation from dual-wavelength optoacoustic measurements

We developed a novel machine-learning-based algorithm based on a gradient boosting regressor for three-dimensional pixel-by-pixel mapping of blood oxygen saturation based on dual-wavelength optoacoustic data. Algorithm training was performed on in silico data produced from Monte-Carlo-generated absorbed light energy distributions in tissue-like vascularized media for probing wavelengths of 532 and 1064 nm and the empirical instrumental function of the optoacoustic imaging setup with further validation of the independent in silico data. In vivo optoacoustic data for rabbit-ear vasculature was employed as a testing dataset. The developed algorithm allowed in vivo blood oxygen saturation mapping and showed clear differences in blood oxygen saturation values in veins at 15 °C and 43 °C due to functional arteriovenous anastomoses. These results indicated that dual-wavelength optoacoustic imaging could serve as a cost-effective alternative to complicated multiwavelength quantitative optoacoustic imaging.

Sex-Linked Differences in Pulmonary Functions of COVID-19 Patients After a Six-Minute Walk Test.

Coronavirus disease 2019 (COVID-19) predominantly impacts the respiratory system. Historically, numerous lung diseases have shown sex-related differences throughout their progression. This study aimed to identify sex-linked disparities in pulmonary function tests (PFTs) among individuals who have recovered from COVID-19 when subjected to a six-minute walk test (6MWT). In this observational cross-sectional study, we analyzed 61 participants, consisting of 39 (64%)males and 22 (36%) females, all of whom previously contracted COVID-19 three months or more prior. We measured vitals such as blood pressure, pulse, oxygen saturation, and PFT values before and after the 6MWT. The post-6MWT evaluation revealed notable mean differences between males and females in parameters systolic blood pressure (SBP) (p = 0.003), diastolic blood pressure (DBP) (p = 0.026), forced expiratory volume in the first second (FEV1) (p = 0.038), forced vital capacity (FVC) (p = 0.041), and maximum voluntary ventilation (MVV) index (p = 0.011). PFT outcomes indicated sex-based variations among post-COVID-19 subjects. Specifically, post-stress values for FEV1, FVC, MVV index, SBP, and DBP were more elevated in males than in females. However, females presented with higher oxygen saturation levels post-COVID-19 compared to males. Using multiple linear regression modeling, sex was not found to be a strong predictor of PFT results. However, individual regression analyses for FEV1, FVC, and MVV index consistently showcased higher values in males. In conclusion, significant PFT differences exist between males and females after recovery from COVID-19 when exposed to stress induction via the 6MWT.

RISK FACTORS FOR UNFAVORABLE PROGNOSIS AND PROGRESSION OF CHRONIC HEART FAILURE IN COVID-19 PNEUMONIA

Introduction. Patients with chronic heart failure are vulnerable to coronavirus disease (COVID-19).
 Objectives. To investigate risk factors for unfavorable prognosis and progression of heart failure in hospitalized patients with chronic heart failure and COVID-19 pneumonia.
 Methods. A retrospective analysis of the medical records of 555 hospitalized patients diagnosed with COVID-19 was conducted. Subsequently, the data of 90 patients with chronic heart failure (CHF) and COVID-19 pneumonia from January – February 2021 were collected at Lviv Clinical Hospital of Emergency Medical Care. The following indices were evaluated: anthropometric and demographic data, complications, treatment results, results of clinical, laboratory, and instrumental examinations, and dynamic NT-proBNP.
 Results. CHF is recorded in 42.9% of hospitalized patients with COVID-19 and is accompanied by lower values of blood oxygen level (p=0.0474), hemoglobin (p=0.0090), prothrombin time (p=0.0196), prothrombin index (p=0.0196) and higher indicators of glucose (p=0.0032), creatinine (p=0.00001), interleukin-6 (p=0.0041). CHF decompensation is associated with lower values of body temperature (p=0.0047) and blood oxygen saturation (p=0.0076), while hemoglobin level (p=0.0026), higher creatinine values (p=0.0034), interleukin-6 (p=0.0300), aspartate aminotransferase (p=0.0035), troponin I (p=0.0061); are associated with the development of myocardial infarction (p=0.0014), acute arrhythmias (p=0.0011), hypertensive crisis (p=0.0096) and increased mortality (OR=5.72; 95). % CI: 1.84, 17.81; p=0.0026).
 Conclusions. CHF is common and often fatal in patients with COVID-19, especially in decompensated CHF. Low blood oxygen saturation, myocardial infarction, arrhythmia, hypertensive crisis, increased cardio cytolysis markers and pro-inflammatory cytokines preceding adverse cardiovascular risk factors contribute to CHF decompensation in patients with COVID-19.

Evaluation of Clinical Features and Olfactory Functions in COVID-19: A Multicentre Study.

Introduction Coronavirus Disease-2019 (COVID-19) causes olfactory loss one of the initial diagnostic criteria. The brief smell identification test (BSIT) is an objective test frequently used in olfactory dysfunction. This study aimed to observe the changes in olfactory functions and clinical features in a short time in COVID-19. Methods In this prospective study involving 64 patients, the BSIT was performed at two different times; at the time of first application and on the 14th day. Demographic features, laboratory findings, body mass index (BMI), blood oxygen saturation values (SpO2), complaints at first admission, fever, follow-up place, and treatment schemes were noted. Results There was a significant difference between the BSIT scores at the first admission and when the polymerase chain reaction (PCR) became negative on the 14th day (p<0.001). Low oxygen saturation values at first admission were associated with low BSIT scores. No relationship was found between olfactory functions and complaints at admission, fever, follow-up place, and treatment schemes. Conclusion As a result, negative effects of COVID-19 on olfactory functions have been demonstrated even in the short follow-up period. In addition, low saturation values at first admission were associated with low BSIT scores.

Associations between indicators of new semi-quantitative express-test for procalcitonin and indicators of saturation in patients with community-acquired pneumonia

Objective. To evaluate the associations between the indicators of a new semi-quantitative express-test for procalcitonin and saturation levels in hospitalized patients with community-acquired pneumonia.&#x0D; Due to a high rate of growth of the incidence of severe community-acquired pneumonia, which leads to disability of the working population and claims thousands of lives, there is a need for early verification of the severity degree and a timely initiation of treatment. Traditional clinical, radiologic, laboratory and bacteriological criteria for inflammatory reactions (fever, increased pulmonary infiltration and leukocytosis, detection of potential pathogens in sputum or hemocultures) are not specific for pneumonia. Similar clinical and radiologic manifestations can also be noted in other pathological conditions, for example, in atelectasis of the lung, lung infarction, congestive heart failure, as well as acute respiratory distress syndrome. In this regard, the study of new diagnostic markers of community-acquired pneumonia is an actual direction in modern therapeutic diagnostics. Being a fast and highly sensitive method, the express test for procalcitonin can be a valuable predictive marker for the severe course of community-acquired pneumonia. Of interest is the relationship of procalcitonin with an indicator reflecting the presence of respiratory failure the level of saturation.&#x0D; Materials and methods. A single-stage comparative study involved 123 patients admitted to the hospital with a confirmed diagnosis of community-acquired pneumonia. On the first day after admission to the hospital, all patients underwent a general clinical examination, an overview X-ray of the chest organs, and determination of the plasma procalcitonin level using a semi-quantitative express-test as well as the saturation level. According to the results of the examination, the patients were divided into two groups: patients with saturation 94 % (n=43), and patients with saturation 94 % (n=80). The group of patients with saturation values 94 % consisted of 23 (53.5 %) women and 20 (46.5 %) men. The group of patients with saturation values 94 % consisted of 42 (52.5 %) women and 38 (47.5 %) men. The mean age of the patients was 56.719.1 and 45.620.7 (MSD) years, respectively, p=0.005. Statistical processing of the obtained data was carried out using the SPSS 13.0 software package.&#x0D; Results. Patients with low saturation values ( 94 %) had higher heart rate (p=0.001) and respiratory rate (p=0.001), and the levels of erythrocytes (p=0.001), hemoglobin (p=0.003) and albumin (p=0.001) were significantly lower than in patients with higher saturation levels 94 %. For patients with signs of respiratory failure and saturation indices 94 %, a more pronounced increase in the level of express-test for procalcitonin was characteristic (p=0.001). According to regression analysis, the express-test for procalcitonin 2 ng/ml by 13.8 % (CI 1.5131.3), age by 3 %, and heart rate by 11 % increase the risk of low saturation in patients with community-acquired pneumonia.&#x0D; Conclusion. Low values of blood oxygen saturation 94 % in hospitalized patients with community-acquired pneumonia are directly associated with high values of the new semi-quantitative express-test for procalcitonin (more than 2 ng/ml), that can be used for individual risk stratification.

Comparative effects of wearing N95, surgical, cloth, and PM2.5 masks during six-minute walk test on dyspnea, breathing effort, oxygen saturation, and functional capacity in pre-aging individuals

Background: Wearing a face mask became a part of daily life due to the COVID-19 pandemic and fine particulate matter (PM2.5) air pollution in Thailand. However, performing activities while wearing different types of masks can cause different physiological effects, especially in the pre-aging population that still performs outdoor activities regularly. Objectives: To compare the impacts of different types of the mask (no mask, N95, surgical, cloth, PM2.5 mask) on dyspnea, breathing effort, blood oxygen saturation (SpO2), and functional capacity (six-minute walk distance and estimated VO2max) during the six-minute walk test (6MWT) in pre-aging individuals. Materials and methods: Twenty-four healthy pre-aging individuals (54±3 years) performed five trials of 6MWT wearing different types of masks. Pre-test and post-test of dyspnea, breathing effort, and blood oxygen saturation values were recorded. The estimated VO2max was calculated from 6MWT. The satisfaction for each type of mask was collected using questionnaires. Results: SpO2, walking distance, and estimated VO2max were not significantly different (p&gt;0.05) among all trials. Changes in dyspnea, breathing effort, and systolic blood pressure values were statistically different (p=0.026, p=0.031, and p=0.028, respectively). Despite post hoc analysis revealing a nonsignificant difference in delta changes in dyspnea between walking trials, there was a clinical difference in dyspnea while wearing N95 compared to no mask as well as surgical masks compared to other masks (MCID for Borg scale ≥1). Wearing an N95 or surgical mask resulted in higher dyspnea. Moreover, wearing an N95 mask also resulted in higher breathing effort and systolic blood pressure compared to wearing no mask. Conclusion: Wearing various types of masks in the pre-aging population during moderate-intensity activity did not result in differences in oxygen saturation and functional capacity. Wearing an N95 resulted in higher levels of dyspnea, breathing effort and systolic blood pressure than wearing no mask. Wearing a surgical mask may have resulted in higher levels of dyspnea than wearing no mask, a cloth mask, or a PM2.5 mask.

Reliability of smartphone measurements of peripheral oxygen saturation and heart rate in hypotensive patients measurement of vital signs with smartphones

ObjectiveWith the increasing use of wearable technologies (smartphones and smartwatches), it has become possible to measure vital signs outside healthcare institutions without the need for an additional medical device. With the advancement in technologies, the accuracy of vital signs measured by smartphones and smartwatches has also increased. In this study, the accuracy of smart devices in the measurement of heart rate and saturation, which are two vital signs that are difficult to detect in conditions such as hypotension were investigated. Materials and methodsThe study was prospectively conducted in a tertiary healthcare center. In hypotensive patients who presented to the emergency department (ED) and required an arterial blood gas evaluation, oxygen saturation and heart rate values measured by a smartphone, those measured with a vital signs monitor (VSM) at the time of admission to the ED and oxygen saturation values measured by a blood gas analyzer (BGA) were compared. ResultsA total of 200 patients, 117 women and 83 men, were included in the study. It was determined that the correlation coefficients of the heart rate values measured by the vital signs monitor and smartphone were in a high statistical agreement. When the saturation values measured by the vital signs monitor, smartphone, and blood gas analyzer were compared, it was found that the intra-class correlation coefficients of the saturation values measured by the smartphone with reference to the blood gas analyzer and vital signs monitor were 0.957 and 0.949, respectively, indicating an excellent agreement. ConclusionSmartphones have as high efficiency as reference devices in measuring heart rate and saturation in hypotensive patients. In this way, hypotensive patients who need medical help can also have the opportunity to measure their vital parameters with their smartphones, without the need for any other medical device, before applying to the hospital or emergency health system. This may contribute to the improvement of the quality of life of the patients and the early and accurate information of the health care providers about the patient's health parameters.

Combined Monte Carlo and k-Wave Simulations for Reconstruction of Blood Oxygen Saturation in Optoacoustics: A Pilot Study

Optoacoustic (OA) imaging of biological tissues is a modern technique allowing for three-dimensional blood oxygen saturation mapping based on OA spectroscopy data. Since biological tissues are optically inhomogeneous and the spatial distribution of optical parameters within a biological tissue is a priori unknown, Monte Carlo simulation technique is traditionally used to estimate the distribution of probing illumination within tissues in quantitative OA reconstruction. Currently, machine learning techniques are actively employed for reconstructing 3D distribution of blood oxygen saturation or estimating optical properties of biological tissues based on training datasets. In this paper, systemic calculations of synthetic OA images of a medium with embedded vessel-like structures were performed to create a training dataset for machine learning employing combined application of the Monte Carlo technique for direct solution of optical problem and difference-space pseudo-spectral approach implemented through k-Wave Toolbox calculations for the acoustical part. The calculations were performed for probing wavelengths of 532 nm, 658 nm and 1064 nm, which are commonly employed in spectral OA imaging. Simulated OA data for different orientation, diameter and embedding depth of blood vessels allows analyzing the effect of these parameters on the formation of OA image and the reconstruction of blood oxygen saturation. The ratio of OA signals corresponding to probing wavelengths of 658 nm and 1064 nm was employed for simple reconstruction of blood oxygen saturation in silico for different vessel geometries with the precision of &lt; 3–15% for the most of blood vessels diameters and embedding depths and the range of blood oxygen saturation values ≥ 0.8. The obtained set of synthetic OA data has high potential as a training set for employment in machine learning techniques aiming at mapping blood oxygenation based on spectral OA data.

Assessment of Relationship between Hemodynamic Changes and Anxiety in Patients During Lower Third Molar Surgery.

To investigate the relationship between anxiety and hemodynamic changes in patients who have undergone impacted third molar surgery under local anaesthesia. Observational clinical study. Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Gazi University, Ankara, Turkey, from January 2018 to December 2019. Normotensive patients aged over 18 years, not using antidepressant medicine and ASA I included. A total of 83 patients were monitored and operated on for impacted third molar surgery. Blood pressure, pulse, and oxygen saturation values of the patients were noted at eight different stages during the surgery. Only the mesioangular impacted lower third molars of the patients were removed by a surgical operation. STAI forms were given before the operation. There is a significant difference between values of blood pressure, pulse, and oxygen saturation and gender (p<0.05). However, there was found to be an increased blood pressure in male patients while an increase in pulse and oxygen saturation was observed in female patients (p<0.05). Male patients were more concerned than female patients by having higher blood pressure which may cause longer postoperative bleeding. Anxiety, Impacted third molars, Dental surgery, Hemodynamic changes.

How does multi-set high-load resistance exercise impact neuromuscular function in normoxia and hypoxia?

ABSTRACT This study examined whether hypoxia during multi-set, high-load resistance exercise alters neuromuscular responses. Using a single-blinded (participants), randomised crossover design, eight resistance-trained males completed five sets of five repetitions of bench press at 80% of one repetition maximum in moderate normobaric hypoxia (inspiratory oxygen fraction = 0.145) and normoxia. Maximal isometric bench press trials were performed following the warm-up, after 10 min of altitude priming and 5 min post-session (outside, inside and outside the chamber, respectively). Force during pre-/post-session maximal voluntary isometric contractions and bar velocity during exercise sets were measured along with surface electromyographic (EMG) activity of the pectoralis major, anterior deltoid and lateral and medial triceps muscles. Two-way repeated measures ANOVA (condition×time) were used. A significant time effect (p = 0.048) was found for mean bar velocity, independent of condition (p = 0.423). During sets of the bench press exercise, surface EMG amplitude of all studied muscles remained unchanged (p > 0.187). During maximal isometric trials, there were no main effects of condition (p > 0.666) or time (p > 0.119), nor were there any significant condition×time interactions for peak or mean forces and surface EMG amplitudes (p > 0.297). Lower end-exercise blood oxygen saturation (90.9 ± 1.8 vs. 98.6 ± 0.6%; p < 0.001) and higher blood lactate concentration (5.8 ± 1.4 vs. 4.4 ± 1.6 mmol/L; p = 0.007) values occurred in hypoxia. Acute delivery of systemic normobaric hypoxia during multi-set, high-load resistance exercise increased metabolic stress. However, only subtle neuromuscular function adjustments occurred with and without hypoxic exposure either during maximal isometric bench press trials before versus after the session or during actual exercise sets. Highlights Performing multi-set, high-load bench press resistance exercise in hypoxia accentuates metabolic stress, as evidenced by lower arterial oxygen saturation and higher blood lactate concentration, compared to normoxia. Acute hypoxic exposure doesn’t alter neuromuscular responses during the execution of the sets since mean bar velocity dropped similarly in both conditions from set 2 to set 5 with no difference in peak velocity and surface EMG amplitude of the prime movers during the bench press. Only subtle adjustments in peak or mean force and accompanying surface EMG activity occur with and without hypoxic exposure during maximal isometric bench press trials after a 10-min hypoxic priming period and 5 min after the session in reference to post-warm-up.

Correlation between chest CT severity scoring system with oxygen saturation and laboratory inflammatory markers in adult patients with COVID-19 infection

BackgroundCOVID-19 pneumonia is responsible for the latest pandemics. Chest computed tomography (CT) scan is known to be an essential tool for diagnosis of COVID-19. In this research, the relationship between on-admission chest CT severity score, capillary blood oxygen saturation level, and laboratory inflammatory markers results in patients with SARS-COV-2 pneumonia was investigated.MethodsThis prospective analytical study was conducted in COVID-19 isolation unit, Zagazig University Hospitals, from 1st to end of April 2021. Adult patients with COVID-19 infection were included. Chest CT scan was performed for all patients, and CT severity score was computed. The initial capillary oxygen saturation was also assessed at the time of admission. The information was gathered and analyzed.ResultsA total number of 305 COVID-19 patients were involved in the study with the following data: age, gender, presence of co morbidities, capillary blood oxygen saturation, laboratory tests including absolute lymphocytic count, CRP, D-dimer and ferritin levels, as well as chest CT severity score. Based on chest CT severity score, we found that 110 cases (36.1%) were mild, 163 cases (53.4%) were moderate, and 32 cases (10.5%) were severe, with significant male predominance among moderate and severe cases. The initial measurements of blood oxygen saturation values revealed that mean blood oxygen saturation was 95.6% among mild to moderate cases and 85.4% among severe cases. Furthermore, there was a high statistically significant negative correlation between chest CT severity score and absolute lymphocytic count of studied cases, while there was a statistically significant positive correlation with D-dimer, CRP and ferritin levels.ConclusionsCT scans can help clinicians in developing a management strategy and serve as a predictor of illness severity and possible outcomes. In individuals with COVID-19 infection, the severity of a chest CT scan is positively correlated to inflammatory markers and oxygen demand.

Effect of a 3% gelatin solution on urinary KIM-1 levels in patients after thyroidectomy: a preliminary randomized controlled trial

Optimal fluid therapy significantly affects the maintenance of proper tissue perfusion and, consequently, kidney function. An adverse effect of colloids on kidney function is related to the incidence of postoperative kidney failure. The study aimed to assess the effect of a 3% gelatin solution on kidney function based on the urinary kidney injury molecule-1 (uKIM-1) level. This study used a parallel design and enrolled 64 adult patients with a mean age of 52.5 ± 13.1 years, all of whom underwent a thyroidectomy procedure under general anesthesia. Patients were randomly assigned to three comparison groups, each receiving a different dose of 3% gelatin solution during the thyroidectomy procedure. The patients from study groups A (n = 21) and B (n = 21) received a 3% gelatin solution at a dose of 30 ml/kg and 15 ml/kg body weight, respectively, during the first hour of the procedure. The patients from the control group C (n = 22) received an isotonic multi-electrolyte solution. Serum creatinine levels were determined, and urine samples were collected to determine levels of uKIM-1 before, 2 h, and 24 h after surgery. The patients’ demographic data, type and volume of fluid and hemodynamic status during the surgery were collected from relevant anesthesia protocols and were included in the study data. There were no statistically significant changes between groups in hemodynamic parameters such as systolic and diastolic blood pressure, heart rate, and oxygen saturation values. A statistically significant increase in uKIM-1 level was noted in patients receiving the 3% gelatin solution regardless of the dose. A statistically significant difference in uKIM-1 level was observed between groups A, B, and C measured 24 h after surgery, with the highest uKIM-1 level in group A. Measurement of uKIM-1 level could be an early and sensitive biomarker of kidney injury. Kidney toxicity of a 3% gelatin solution, evaluated based on the level of uKIM-1 in urine, correlates with transfused fluid volume. This study was retrospectively registered in the ISRCTN clinical trials registry (ISRCTN73266049, 08/04/2021: https://www.isrctn.com/ISRCTN73266049).

Combined spinal epidural anesthesia in obese parturients undergoing cesarean surgery

There is asignificant increase in number of obese pregnant women worldwide. Obese parturients undergoing cesarean section have a higher risk for hypotension and require higher doses of vasopressors following spinal anesthesia compared to nonobese parturients. This study aimed to compare the maternal hemodynamic changes when combined spinal-epidural anesthesia (CSEA) is induced in the left lateral decubitus and sitting positions in obese pregnant women undergoing elective cesarean section. In this study, pregnant women with full-term gestation diagnosed as obese undergoing elective cesarean section were included. Two groups were formed: the CSEA was performed in left lateral position in groupI (n = 50) and in sitting position in groupII (n = 50). At the end of the CSEA procedure, patients were placed in the supine position. When the sensory block reached at the upper level of T6 dermatome, surgery was initiated. Hemodynamic, anesthetic and neonatal parameters were recorded. In all patients, CSEA was successful and sufficient anesthesia was provided for surgery. Time to reach T6 dermatome sensory level in groupII was found to be longer than groupI (P = 0.011). At 20 min after spinal injection, the maximum sensory block level was similar in both groups. There were no significant differences between groups in terms of sensory block time and the time to requiring postoperative supplemental analgesics. There were no significant differences in terms of the volume of intravenous fluid administered, ephedrine and atropine requirements between groups. Both groups had similar systolic blood pressure, heart rate and oxygen saturation values during surgery and postoperatively. While both groups had similar diastolic blood pressure (DBP) values during surgery and at the 1st postoperative hour, groupII had lower DBP values at the 2nd postoperative hour compared with groupI (P = 0.04). Left lateral decubitus and sitting positions during performance of CSEA lead to similar maternal hemodynamic changes in obese pregnant women undergoing cesarean section.

Efficiency of antiviral treatment in COVID-19.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic is responsible for generating a global effort to discover urgent therapeutic solutions to limit the human damage caused by COVID-19. In the period of April to June 2020, 105 patients diagnosed with COVID-19 met the conditions for inclusion in the present study. They were treated with antiviral therapy according to local guidelines: D group (53 cases), treated with darunavir/ritonavir (DRV/r); and K group (52 cases), treated with lopinavir/ritonavir (LPV/r). Patients from the K group required 7.5 days of hospitalization less compared to those from the D group (P<0.001). The blood oxygen saturation values recorded in the groups were statistically different [K group (94.02±3.12%) vs. D group (92.13±4.24%), P=0.010]. The percentage of patients with unsatisfactory clinical evolution were non-significantly higher in the D group compared with the K group [20 (37.74%) vs. 12 (23.08%), P=0.157]. We did not note statistically significant differences between the two groups tracked considering the values for the Brescia-COVID Respiratory Severity Scale (BCRSS) of the patients with unsatisfactory clinical evolution, nor of the chest CT' evolution after 10 days of therapy. We did not register significant adverse effects after antiviral therapy in the two groups. Antiviral therapy with LPV/r had some favorable results compared to DRV/r in patients with COVID-19. Both therapies were well tolerated.

Midazolam and dexmedetomidine sedation impair systolic heart function.

Sedation is an essential part of clinical practice. Despite this fact, we still lack data describing the exact impact of sedation on heart function. To compare the changes in heart function, induced after sedation with either midazolam or dexmedetomidine, using cardiac magnetic resonance imaging (MRI). A total number of 30 volunteers were randomized into two groups: 15 participants in the midazolam group (MID) and 15 participants in the dexmedetomidine group (DEX). Every participant underwent a one-session cardiac MRI before and after sedation onset. The following parameters were recorded: left and right ventricle stroke volume (Ao-vol and Pul-vol resp.) and maximum flow velocity through the mitral valve during early (E-diast) and late diastole (L-diast). A monitor recorded values of mean blood pressure (MAP), pulse (P) and blood oxygen saturation (SpO2) in 5-minute intervals. Dexmedetomidine led to a statistically significant decrease in Ao-vol (p = 0.006) and Pul-vol (p = 0.003), while midazolam decreased E-diast (p = 0.019) Ao-vol (p = 0.001) and Pul-vol (p = 0.01). The late diastolic filling was not influenced by the sedation technique. Both sedation regimens worsened the systolic function of both ventricles. Midazolam moreover attenuated early diastolic filling of the left ventricle (Tab. 3, Fig. 4, Ref. 19).

Photoplethysmography in postoperative monitoring of deep inferior epigastric perforator (DIEP) free flaps

Objective: Deep inferior epigastric perforator (DIEP) free flaps are widely used as a reconstruction option following mastectomy in breast cancer. During such cases partial tissue necrosis can occur due to the insufficient blood supply to the transplanted tissue site. Therefore, monitoring of flap perfusion and early detection of flap failure is a prerequisite to flap survival. There is a need to develop a non-invasive, easy to use, reproducible and inexpensive monitoring device to assess flap perfusion postoperatively. Approach: A three-wavelength reflective optical sensor and processing system based on the principle of photoplethysmography (PPG) has been developed to investigate blood volumetric changes and estimate free flap blood oxygen saturation continuously and non-invasively in DIEP free flaps in the postoperative period. The system was evaluated in 15 patients undergoing breast reconstructive surgery using DIEP free flap. Main results and Significance: Good quality red, infrared and green PPG signals were obtained in the postoperative period. Initial estimation of blood oxygen saturation values estimated from the free flap PPGs seem to be in broad agreement with the commercial finger pulse oximeter used in this study. This pilot study has demonstrated that PPG has the potential to be used as a monitoring technique in assessing free flap viability.

Impact of High-Flow Nasal Cannula on Arterial Blood Gas Parameters in the Emergency Department.

Background: High-flow nasal cannula (HFNC) oxygen is becoming an integral part of respiratory failure management. Effects of HFNC on arterial blood gas (ABG) parameters especially partial carbon dioxide (PaCO2) require further investigation to provide insight into the efficacy and safety of the treatment.Methods: Acute respiratory failure patients with sequential ABG parameters before and after initiating HFNC between June 2015 and June 2017 were analyzed in a tertiary academic center. Patients' baseline characteristics were evaluated and sequential ABG changes were compared and subgrouped as chronic obstructive pulmonary disease (COPD), respiratory acidosis, hypercapnia, and high lactate.Results: A total of 120 patients were enrolled in the study. There was a significant difference between the mean partial pressure of oxygen in arterial blood (PaO2), lactate, and peripheral oxygen saturation (SpO2) values between sequential ABGs after HFNC (P <0.001). In the COPD group (n=32), there was a significant difference between initial ABG means of PaO2, lactate, and SpO2 values and sequential ABG means (p<0.001). Hypercapnic patients PaCO2 levels were significantly lower after HFNC (p<0.001), while in the COPD group there was no significant change in PaCO2 values (p=0.068).Conclusions: Treatment with HFNC produced improvement of blood gas parameters in subjects with acute respiratory failure in the emergency department (ED). These results suggest that HFNC can be used in hypercapnic patients as well as hypoxemic patients. Further randomized controlled studies required to establish the impact of HFNC in the ED.

Apneic Event Estimation only using SpO2 Dynamics in Sleep Apnea Patients.

Nocturnal pulse oximetry has been proposed as a tool for diagnosing sleep apnea. We established criteria in determining previous occurrences of apnea events by extracting quantitative characteristics caused by apnea events over the duration of changes in blood oxygen saturation values in our previous studies. In addition, the apnea-hypopnea index was estimated by regression modeling. In this paper, the algorithm presented in the previous study was applied to the data collected from the sleep medicine center of other hospitals to verify its performance. As a result of applying the algorithm to pulse oximetry data of 15 polysomnographic recordings, the minute-by-minute apneic segment detection exhibited an average accuracy of 87.58% and an average Cohen's kappa coefficient of 0.6327. In addition, the correlation coefficient between the estimated apnea-hypopnea index and the reference was 0.95, and the average absolute error was 5.02 events/h. When the algorithm is evaluated on the data collected by the other sleep medicine center, they still detected semi real-time sleep apnea events and showed meaningful results in estimating apnea-hypopnea index, although their performance was somewhat lower than before. With the recent popularity of devices for mobile healthcare, such as the wearable pulse oximeter, the results of this study are expected to improve the user value of devices by implementing mobile sleep apnea diagnosis and monitoring functions.