SpO2 Values Research Articles

Continuous measurement of percutaneous oxygen saturation during 6-minute walk test is useful for stratification of the prognostic risk in patients with heart failure

Abstract Background The 6-minute walk test (6MWT) is an established test to assess the functional exercise performance and the 6-minute walk distance is strongly correlated with the functional capacity and the prognosis in patients with heart failure (HF). Also, the hypoxia during 6MWT is reported to be associated with severity of pulmonary diseases. However, no study has reported the clinical implication of sequential changes in percutaneous oxygen saturation (SpO2) during 6MWT was not investigated in HF patients. Purpose To prospectively clarify the association between sequential changes in SpO2 during 6MWT and prognosis in patients with HF. Methods In this prospective observational study, 50 patients admitted to our hospital with acute heart failure were enrolled. The 6MWT was performed at the time before discharge, after hemodynamic stability was confirmed. The average of SpO2 was calculated from data obtained at rest (3 minutes just before the test) and during 6MWT by employing the wearable pulse-oximeter which are designed to record and store the SpO2 value every seconds. Alternations in SpO2 (Δ SpO2) were analyzed by subtracting the average during 6MWT from that at rest. Patients were followed 1 year for composite outcome of heart failure-hospitalization and death). Results The mean age of participants was 78.8 years, and 23 (46%) were female. The mean EF was 46.1% and the number of the patients with EF≧50, 50>EF>40, 40≧EF were 22, 6, and 22, respectively. Mean NT-proBNP was 4374.5pg/ml. The mean walk distance was 250 ± 112m and the mean Δ SpO2 was 2.88 ± 4.3%. All cases were classified by walk distance and Δ SpO2; long- (>220m) vs. short-distance group (≦220m) and low- (<3.5%) vs. high-ΔSpO2 group (≧3.5%). There were no significant differences in cardiac parameters and respiratory function between long- and short-distance group as well as between low- and high-ΔSpO2 group. Kaplan-Meier analysis revealed that cardiac event rate was higher in the short-distance group than in the long-distance group (HR = 2.89, CI = 1.24-6.71, p = 0.014), and higher in the high-Δ SpO2 group than in the low-ΔSpO2 group (HR = 3.49, CI = 1.55-7.83, p = 0.002) (Figure 1A and 1B). When these classifications were combined, the patients with short-distance and low-ΔSpO2 showed remarkably high event rate of 91% (Figure 2). Conclusions This study showed that, compared to walk distance, ΔSpO2 was more predictive of prognosis of heart failure patients, and that the combination of ΔSpO2 and walk distance may identify the highest risk group. The elucidation of the usefulness of continuous SpO2monitoring during 6MWT as the marker for severity of heart failure and treatment effect warrants further investigation.Figure1Figure 2

Abstract 12748: Continuous Measurement of Percutaneous Oxygen Saturation During 6-Minute Walk Test is Useful for Predicting the Prognostic Risk in Patients With Heart Failure

Background: The 6-minute walk test (6MWT) is an established test to assess functional exercise performance and the 6-minute walk distance (6MWD) is strongly correlated with the functional capacity and the prognosis in patients with heart failure (HF). However, the clinical implication of sequential changes in percutaneous oxygen saturation (SpO2) during 6MWT has not been investigated in HF patients. Purpose: To prospectively clarify the association between sequential changes in SpO2 during 6MWT and prognosis in patients with HF. Methods: Fifty patients admitted with acute heart failure were enrolled. The 6MWT was performed at the time before discharge, after hemodynamic stability was confirmed. The average of SpO2 was calculated from data obtained at rest and during 6MWT by employing the wearable pulse-oximeter which is designed to record the SpO2 value every second. Alternations in SpO2 (ΔSpO2) were obtained by subtracting the average during 6MWT from that at rest. Patients were followed up to 9 months for the composite outcome of heart failure-hospitalization and death. Results: The mean age of participants was 78.8 years, and 23 (46%) were female. The mean EF was 46.1% and the number of patients with EF ≦40 was 22. The 6MWD was 250 ± 112m and the ΔSpO2 was 2.88 ± 4.3%. All cases were classified by walk distance and ΔSpO2; long- (>220m) vs. short-distance group (≦220m) and low- (<3.5%) vs. high-ΔSpO2 group (≧3.5%). There were no significant differences in cardiac parameters and respiratory function between long- and short-distance group as well as between low- and high-ΔSpO2 group. Kaplan-Meier analysis revealed that higher ΔSpO2 showed a more strong and statistically significant impact on cardiovascular outcome compared to longer 6MWD (HR=3.25, CI=1.40-7.51, p=0.006, HR=2.24, CI=0.94-5.32, p=0.067, respectively). Conclusions: This study showed that, compared to walk distance, ΔSpO2 during 6MWT was more predictive of the prognosis of heart failure patients.

Experiences of Patients With Chronic Obstructive Pulmonary Disease Using the Apple Watch Series 6 Versus the Traditional Finger Pulse Oximeter for Home SpO2 Self-Monitoring: Qualitative Study Part 2

Background Amid the rise in mobile health, the Apple Watch now has the capability to measure peripheral blood oxygen saturation (SpO2). Although the company indicated that the Watch is not a medical device, evidence suggests that SpO2 measurements among patients with chronic obstructive pulmonary disease (COPD) are accurate in controlled settings. Yet, to our knowledge, the SpO2 function has not been validated for patients with COPD in naturalistic settings. Objective This qualitative study explored the experiences of patients with COPD using the Apple Watch Series 6 versus a traditional finger pulse oximeter for home SpO2 self-monitoring. Methods We conducted individual semistructured interviews with 8 female and 2 male participants with moderate to severe COPD, and transcripts were qualitatively analyzed. All received a watch to monitor their SpO2 for 5 months. Results Due to respiratory distress, the watch was unable to collect reliable SpO2 measurements, as it requires the patient to remain in a stable position. However, despite the physical limitations and lack of reliable SpO2 values, participants expressed a preference toward the watch. Moreover, participants’ health needs and their unique accessibility experiences influenced which device was more appropriate for self-monitoring purposes. Overall, all shared the perceived importance of prioritizing their physical COPD symptoms over device selection to manage their disease. Conclusions Differing results between participant preferences and smartwatch limitations warrant further investigation into the reliability and accuracy of the SpO2 function of the watch and the balance among self-management, medical judgment, and dependence on self-monitoring technology.

Predictive model for estimating the risk of high-altitude pulmonary edema: a single-centre retrospective outcome-reporting study

ObjectiveTo develop the first prediction model based on the common clinical symptoms of high-altitude pulmonary edema (HAPE), enabling early identification and an easy-to-execute self-risk prediction tool.MethodsA total of 614 patients...

Evaluation of the pleth variability index, perfusion index, and other physiological parameters after COVID-19.

The aim of this study was to observe the changes in pleth variability index (PVI), perfusion index (PI) and other hemodynamic parameters in adult individuals who had had Coronavirus disease 2019 (COVID-19) and were currently living a normal life. A further aim was to draw attention to the fact that some hemodynamic changes after COVID-19 may cause long-term health problems. A total of 174 adult individuals who had had COVID-19 and were currently living a normal life and 56 healthy individuals with similar demographic characteristics who had not had COVID-19 were included in the study. The PI, PVI, oxygen saturation (SpO2), pulse rate (PR), total hemoglobin (Hgb), oxygen reserve index (ORI), and blood pressure values were measured by Masimo Radical 7. The data of individuals who had and did not have COVID-19 before were compared. The mean PVI (p = 0.008) and PI (p < 0.001) were significantly lower in people who had been exposed to COVID-19. Likewise, the mean of ORI, SpO2, and SpOC values was observed to be significantly lower in participants exposed to COVID-19 disease (p < 0.001, p < 0.001, and p = 0.006, respectively). The PVI had a positive correlation with body mass index (BMI) (r = 0.263, p < 0.001) and a negative correlation with SpO2 (r = -0.194, p = 0.003) and PR (r = 0.190, p = 0.004). The PVI, PI, and other physiological parameters could potentially be useful for monitoring COVID-19 patients and evaluating their response to therapy. We believe that people who have been exposed to COVID-19 may be more susceptible to other diseases; therefore, they should be subjected to regular clinical checks.

Effect of CPAP therapy on the reperfusion lung injury after transluminal balloon angioplasty of the pulmonary arteries in patients with chronic thromboembolic pulmonary hypertension

Aim. To evaluate the effect of non-invasive ventilation (NIV) in CPAP (continuous positive airway pressure) mode on the development of reperfusion pulmonary edema after percutaneous balloon pulmonary angioplasty (BPA) in patients with chronic thromboembolic pulmonary hypertension (CTEPH).Materials and methods. The study included 70 patients with CTEPH who underwent the first stage of BPA. Prevention of reperfusion edema was carried out using NIV in the CPAP mode starting from the early postoperative period in combination with oxygen and diuretic therapy (as nedeed). The presence and severity of pulmonary edema was assessed based on clinical signs and data from computed tomography or chest radiography.Results. Patients after BPA were on CPAP therapy: average pressure: 10.0±0,7 hPa. During 1st day, the average time of use was: 990±417 minutes. Prolongation of CPAP therapy &gt;1 day occurred in 26 (37%) patients. Depending on the severity of reperfusion edema to the lungs, patients were divided into 2 groups: group 1 (grade 1, n=42) and group 2 (grade 3-4, n=12). During the observation period, there were no cases of severe reperfusion edema (grade 5), and no cases required the use of invasive ventilation or extracorporeal membrane oxygenation. No complications of CPAP therapy were recorded. The number of PA segments and ΔPFG did not differ, but the PEPSI index was higher in group 2: 41,9 [16,0; 57,9] vs 80.5 [52,5; 111,25], p=0,0146. The number of days before discharge after BPA in patients of group 2 was higher: 4.0 [3,9; 5,5] vs 7,0 [4,6; 10,0] days, p=0,013. Despite the development of reperfusion edema, before discharge the SpO2 values in group 2 were comparable to the baseline: 93,0 [89,9; 94,2] vs 93,0 [89,7; 94,4]Conclusion. Preventive use of NIV in the CPAP mode, starting from the early postoperative period, is safe and makes it possible to achieve optimal clinical results in patients even with moderate and severe lung reperfusion edema after large volumes of surgical intervention.

P064 Predictive Value of Awake Supine Pulse Oxygen Saturation in Detecting Resting Hypercapnoea Prior to Polysomnography

Abstract Introduction Arterial blood gases (ABG) are used during polysomnography (PSG) to assess gas exchange abnormalities in patients at risk of hypercapnoea. ABG sampling may cause discomfort and can be difficult to obtain. Normal, awake, supine finger pulse oxygen saturation (SpO2) immediately prior to PSG may reduce the need for ABG sampling. Aim To determine if an awake supine evening SpO2 cutoff value can exclude awake hypercapnoea measured with ABG testing. Methods : Prospective observational study of all patients referred for diagnostic or treatment PSGs with ABG at Westmead Sleep Laboratory between January 2019 and December 2021. ABGs were requested to exclude hypercapnoea and were collected awake, supine and breathing room air prior to PSG with simultaneous SpO2 measurement. We defined resting hypercapnoea as PaCO2 &amp;gt; 45mmHg. We used 2x2 tables for SpO2 values of 93% to 98% to determine the negative predictive values (NPV) for SpO2 cutoffs and construct a receiver operating characteristic (ROC) curve. Results We analysed 146 patients (60±17 years; 68% male; Body-mass Index 32.7±12.0 kg/m2; mean±SD) and 36 patients (25%) had hypercapnoea. The NPVs for hypercapnoea on the ABG with cut off SpO2 values of 96%, 95%, 94% and 93% were 92%, 92%, 89% and 83%, respectively. The ROC area under curve was 0.75. Conclusion Resting supine oxygen saturation of ≥95% was able to exclude hypercapnoea in 92% of subjects within this sleep population at high risk of hypercapnoea. Thus, an accurate, awake, supine SpO2 ≥95% will fail to diagnose hypercapnoea in ~8% of high risk patients.

O009 Are there Differences in SpO2 Recordings from Two Oximeters on the same hand during an Overnight Sleep Study Significant?

Abstract Background Accurate non-invasive oxygen saturation (SpO2) measurement is crucial in healthcare, however is challenged by numerous devices using variable algorithms1. We compared two commonly used oximeter devices worn simultaneously in patients during an overnight polysomnogram. Aim To assess (1) differences between two SpO2 recording devices and (2) SpO2 accuracy against SaO2. Methods SpO2 data of two devices were recorded, downloaded and analysed with corresponding software: device 1 (Rad7 [Masimo, Irvine, CA, USA] set at 2-4sec averaging time) with software 1 (PSG 4 [Compumedics, Melbourne, Australia]) and device 2 (Wrist-Ox2® [Nonin Medical Inc, Plymouth, MN, USA] set at 3 sec averaging time) with software 2 (Noxturnal [Nox Medical Inc, Reykjavik, Iceland]). Responsiveness of each oximeter to changes in the patients’ desaturations associated with apnoeas and hypopnoeas overnight was assessed. In addition, both device SpO2 values were compared with SaO2 from simultaneous arterial blood gas sampling. Preliminary Results 7 patients (age 56.4±7.1 years, BMI 31.6±2.2 kg/m2, 100% male, 87% light skinned) were studied. The mean SpO2 with RAD7 was higher than the Nonin (95.9±1.6 vs 94.2±1.4%, mean difference 1.6±1.0%). Differences in the responsiveness of the oximeters during overnight desaturations were also observed. However, both device SpO2 values were found to be within ±2% of SaO2. Conclusions Discrepancies in SpO2 measurement do occur between devices and may have important clinical implications especially when it comes to the measurement of hypoxemic burden during sleep. 1.Blanchet MA et al. Accuracy of Multiple Pulse Oximeters in Stable Critically Ill Patients. Respir Care. 2023 May;68(5):565-574.

Enhanced SpO2 estimation using explainable machine learning and neck photoplethysmography

Reflectance-based photoplethysmogram (PPG) sensors provide flexible options of measuring sites for blood oxygen saturation (SpO2) measurement. But they are mostly limited by accuracy, especially when applied to different subjects, due to the diverse human characteristics (skin colors, hair density, etc.) and usage conditions of different sensor settings. This study addresses the estimation of SpO2 at non-standard measuring sites employing reflectance-based sensors. It proposes an automated construction of subject inclusion-exclusion criteria for SpO2 measuring devices, using a combination of unsupervised clustering, supervised regression, and model explanations. This is perhaps among the first adaptation of SHAP to explain the clusters gleaned from unsupervised learning methods. As a wellness application case study, we developed a pillow-based wearable device to collect reflectance PPGs from both the brachiocephalic and carotid arteries around the neck. The experiment was conducted on 33 subjects, each under totally 80 different sensor settings. The proposed approach addressed the variations of humans and devices, as well as the heterogeneous mapping between signals and SpO2 values. It identified effective device settings and characteristics of their applicable subject groups (i.e., subject inclusion-exclusion criteria). Overall, it reduced the root mean squared error (RMSE) by 16%, compared to an empirical formula and a plain SpO2 estimation model.

Are there differences in the relationship between respiratory rate and oxygen saturation between patients with COVID-19 and those without COVID-19? Insights from a cohort-based correlational study

BackgroundPhysicians have observed patients with COVID-19 without respiratory distress despite marked hypoxaemia and extensive radiographic abnormalities, a controversial phenomenon called ‘silent hypoxaemia’. We aimed to compare the relationship between RR...

Relationship of Intraoperative SpO2 and ETCO2 Values with Postoperative Hypoxemia in Elderly Patients after Non-Cardiac Surgery.

Elderly patients are at higher risk of postoperative hypoxemia due to their decreased respiratory function. The aim of this study was to investigate the relationship of intraoperative oxygen saturation (SpO2) and end-expiratory carbon dioxide (ETCO2) values with postoperative hypoxemia in elderly patients. The inclusion criteria were: 1) patients aged≥75 years; 2) underwent general anesthesia in non-cardiac surgery; 3) operative time longer than two hours; and 4) admission to the intensive care unit (ICU) following surgery performed between January and December 2019. Intraoperative SpO2 and ETCO2 values were collected every minute for the first two hours during surgery. The 253 patients were divided into two groups: SpO2≥92% and SpO2<92%. The time-weighted averages of intraoperative SpO2 and ETCO2 were used to compare differences between the two groups. The incidence of postoperative hypoxemia was 22.5%. For similar ventilator settings, patients with postoperative hypoxemia had lower intraoperative SpO2 and higher ETCO2 values. Sex, ASA classification, and intraoperative SpO2 were independent risk factors for postoperative hypoxemia. In conclusion, postoperative SpO2<92% was a frequent occurrence (> 20%) in elderly patients who underwent major non-cardiac surgery. Postoperative hypoxemia was associated with low intraoperative SpO2 and relatively higher ETCO2.

THRIVE combined with i-gel laryngeal mask for prolonging apneic oxygenation time in retrograde intrarenal surgery

To explore the effect of THRIVE combined with i-gel laryngeal mask on the safety of oxygen therapy in apnea and surgical precision of retrograde intrarenal surgery. A total of 120 patients undergoing retrograde intrarenal surgery under general anesthesia with laryngeal mask were randomized into 3 groups (n=40), and after the flexible ureteroscope entered the renal pelvis and located the stones, the patients received assisted ventilation in APPV mode (control group), ventilation with small tidal volume and high respiratory rate (group H), or THRIVE combined with laryngeal mask for oxygen supply without using the ventilator (THRIVE group). The time for lithotripsy by the surgeons, surgeons' satisfaction, diaphragm mobility, and times of urinary tract mucosal injury were recorded, and arterial blood pressure, heart rate, SpO2, PaO2, PaCO2, and pH value were measured before, during and after lithotripsy. Among the 3 groups, THRIVE group had the shortest time for lithotripsy, best satisfaction of the surgeons, the lowest diaphragmatic mobility of the patients, and the smallest number of mucosal injuries. The arterial blood pressure, heart rate, and SpO2 of the patients did not differ significantly among the 3 groups. At 20 min and 30 min after the start of lithotripsy, PaO2 decreased significantly in group H and THRIVE group; in THRIVE group, PaCO2 increased and pH decreased significantly at 10, 20 and 30 min after the start of lithotripsy. No significant difference was found in oxygenation indicators among the 3 groups upon discharge from the PACU. In retrograde intrarenal surgery, THRIVE combined with i- gel laryngeal mask for oxygen therapy during the anaerobic period can improve the surgical accuracy and maintain the patient's oxygenation index in a controllable range within 30 min.

Sleep parameters in patients with chronic hypersensitivity pneumonitis: a case-control study.

To compare patients with chronic hypersensitivity pneumonitis (cHP) and controls with normal spirometry in terms of their sleep characteristics, as well as to establish the prevalence of obstructive sleep apnea (OSA) and nocturnal hypoxemia. Secondary objectives were to identify factors associated with OSA and nocturnal hypoxemia; to correlate nocturnal hypoxemia with the apnea-hypopnea index (AHI) and lung function, as well as with resting SpO2, awake SpO2, and SpO2 during exercise; and to evaluate the discriminatory power of sleep questionnaires to predict OSA. A total of 40 patients with cHP (cases) were matched for sex, age, and BMI with 80 controls, the ratio of controls to cases therefore being = 2:1. The STOP-Bang questionnaire, the Epworth Sleepiness Scale (ESS), the Pittsburgh Sleep Quality Index, the Berlin questionnaire and the Neck circumference, obesity, Snoring, Age, and Sex (NoSAS) score were applied to all cases, and both groups underwent full-night polysomnography. The patients with cHP had longer sleep latency, lower sleep efficiency, a lower AHI, a lower respiratory disturbance index, fewer central apneas, fewer mixed apneas, and fewer hypopneas than did the controls. The patients with cHP had significantly lower nocturnal SpO2 values, the percentage of total sleep time spent below an SpO2 of 90% being higher than in controls (median = 4.2; IQR, 0.4-32.1 vs. median = 1.0; IQR, 0.1-5.8; p = 0.01). There were no significant differences between cases with and without OSA regarding the STOP-Bang questionnaire, NoSAS, and ESS scores. The prevalence of OSA in cHP patients (cases) was high, although not higher than that in controls with normal spirometry. In addition, cases had more hypoxemia during sleep than did controls. Our results suggest that sleep questionnaires do not have sufficient discriminatory power to identify OSA in cHP patients.

The possible effect of light exposure reduction via eye patches after the examination for retinopathy in premature infants? An observational study in preterm neonates

Objectives: This study aimed to examine whether infants with and without eye patches differ in terms of vital signs and clinical status after retinopathy of prematurity examination. Methods: Premature infants hospitalized in study center between June 2021-April 2022 were included. Group 1 is consisted of infants whose eyes were not closed after retinopathy of prematurity examination. Those infants whose eyes were closed eye-patches consisted of group 2. Vital signs were followed for 24 hours following the examination. Demographic, medical and follow-up data were all recorded prospectively. Vital signs were evaluated in accordance with birth week and weight. Pain score was evaluated by Neonatal Pain, Agitation, and Sedation Scale. Results: Pain scores were found to be lower in group 2 (p &amp;lt; 0.020). Although the systolic blood pressure, diastolic blood pressure, and mean blood pressure values of group 2 were found to be lower than group 1, they were within normal limits (all p &amp;lt; 0.05). Vomiting was not observed at all in Group 1 (p = 0.036). There was no significant difference between the groups in terms of fever, respiratory rate, heart rate, SpO2, and blood glucose values. Conclusions: This study showed that using an eye patch in infants after an eye examination reduces pain and increases comfort of infants. Although their pain scores are lower, taking necessary precautions are recommended for these patients in terms of vomiting. Thus, eye patches can be suggested as a non-pharmacological pain-reducing method after get advanced stagnation by the support of more studies with a larger number of participants.

Features of Mechanical Lung Ventilation During Robot-Assisted Radical Prostatectomy in Patients with Different Body Mass Index

The aim of the study. To evaluate effects of carboxyperitoneum and steep Trendenburg position on respiratory biomechanics and gas exchange indicators in patients with different body mass index (BMI) during robotic-assisted radical prostatectomy (RRP). To develop an algorithm for choosing the optimal mechanical lung ventilation (MLV) regimen. Materials and methods. The study included 141 patients with verified prostate cancer who were candidates for RPR. Participants were divided into 2 groups based on BMI: group I included 88 patients with BMI30 kg/m2, group II — 53 patients with BMI30 kg/m2. Indicators of respiratory biomechanics and gas exchange during ventilation in various modes (Volume Controlled Ventilation (VCV), Pressure Controlled Ventilation (PCV), Pressure Controlled– Inverse Ratio Ventilation (PC-IRV) were analyzed in each group at 5 consecutive stages of the procedure.Results. The key parameters evidencing the effectiveness and safety of MLV during RRP procedure did not vary significantly under various ventilation regimens in the group of patients with a BMI30 kg/m2. Whilst in obese patients the use of VCV mode resulted in a significant increase of airway peak pressure (Ppeak) already at the stage of placing them into a steep Trendelenburg position (35°), thus endangering with the development of ventilator-induced lung injury. Increased Ppeak was also accompanied by the drop in oxygen saturation and significantly lower SpO₂ values, starting from the stage of applying carboxyperitoneum and until the end of surgical intervention.Conclusion. In non-obese patients, there’s no particular ventilator regimen that is crucial for achieving the safety and effectiveness of RRP anesthesia management, all regimens can be used. In patients with BMI30 kg/m2 PCV regimen and PC-IRV with inhalation/exhalation ratio of 1.5:1 can be considered as the optimal strategy for MLV during anesthesia for RRP surgery.

Reduced pulmonary oxygen diffusion at 36 weeks of postmenstrual age in small-for-gestational-age preterm infants of less than 32 weeks without bronchopulmonary dysplasia.

Small-for-gestational-age (SGA) preterm infants are at increased risk of developing bronchopulmonary dysplasia (BPD). There is limited information on pulmonary oxygen diffusion of SGA preterm infants, particularly in those without BPD. To compare the pulmonary oxygen diffusion of SGA to that of appropriate-for-gestational-age (AGA) preterm infants without BPD. Preterm infants with a gestational age (GA) between 24.0 and 31.6 weeks were studied. The oxygen saturation (SpO2 ), fraction to inspired oxygen (FiO2 ), and the SpO2 to FiO2 ratio (SFR) were compared between SGA and AGA infants. The association between SGA and SFR at 36 weeks was assessed using a multiple regression analysis. In the subgroup without BPD, SGA were match-paired for GA and gender with AGA infants. We analyzed 1189 infants surviving at 36 weeks: 194 (16%) were SGA and 995 (84%) AGA. The incidence of BPD was significantly higher in SGA than AGA infants (32% vs. 13%; p = .000). Out of the 995 infants without BPD, 132 (13%) were SGA and 863 (87%) AGA. SGA was negatively associated with the SFR value at 36 weeks, independently from BPD. SGA infants without BPD had significantly higher (better) SFR at birth, but lower (worse) SpO2 and SFR and from 33 to 36 weeks than their matched AGA counterpart. At 36 weeks, median SpO2 and SFR values were 97.7 versus 98.4 (p = .006) and 465 versus 468 (p = .010) in match-paired SGA and AGA, respectively. Among preterm infants of less than 32 weeks and without BPD, SGA infants had a reduced pulmonary oxygen diffusion at 36 weeks in comparison with AGA infants.

Repeatability of Pulse Oximetry Measurements in Children During Triage in 2 Ugandan Hospitals.

In low- and middle-income countries, health workers use pulse oximeters for intermittent spot measurements of oxygen saturation (SpO2). However, the accuracy and reliability of pulse oximeters for spot measurements have not been determined. We evaluated the repeatability of spot measurements and the ideal observation time to guide recommendations during spot check measurements. Two 1-minute measurements were taken for the 3,903 subjects enrolled in the study conducted April 2020-January 2022 in Uganda, collecting 1 Hz SpO2 and signal quality index (SQI) data. The repeatability between the 2 measurements was assessed using an intraclass correlation coefficient (ICC), calculated using a median of all seconds of non-zero SpO2 values for each recording (any quality, Q1) and again with a quality filter only using seconds with SQI 90% or higher (good quality, Q2). The ICC was also recalculated for both conditions of Q1 and Q2 using the initial 5 seconds, then the initial 10 seconds, and continuing with 5-second increments up to the full 60 seconds. Lastly, the whole minute ICC was calculated with good quality (Q2), including only records where both measurements had a mean SQI of more than 70% (Q3). The repeatability ICC with condition Q1 was 0.591 (95% confidence interval [CI]=0.570, 0.611). Using only the first 5 seconds of each measurement reduced the repeatability to 0.200 (95% CI=0.169, 0.230). Filtering with Q2, the whole-minute ICC was 0.855 (95% CI=0.847, 0.864). The ICC did not improve beyond the first 35 seconds. For Q3, the repeatability rose to 0.908 (95% CI=0.901, 0.914). Training guidelines must emphasize the importance of signal quality and duration of measurement, targeting a minimum of 35 seconds of adequate-quality, stable data. In addition, the design of new devices should incorporate user prompts and force quality checks to encourage more accurate pulse oximetry measurements.

Comparison of hands-free Trans-nasal Humidified Rapid Insufflation Ventilatory Exchange (THRIVE) with conventional facemask ventilation technique for oxygenation in patients undergoing electroconvulsive therapy – A cross over study

ObjectivesModified ECT is routinely conducted using face mask (FM) and bag ventilation technique. Trans-nasal Humidified Rapid Insufflation Ventilatory Exchange (THRIVE) is a novel hands-free insufflation technique that provides oxygenation and prolongs apnoea time. There is limited literature comparing the two techniques. Primary objective of this study was to compare oxygen desaturation between THRIVE and FM techniques during ECT while secondary objective was to compare hemodynamics and complications. MethodsPatients aged 18–50 years undergoing 3rd-5th ECT treatments were enrolled. First ECT was with FM technique followed by THRIVE (with LUBO collar) in the next ECT. Except for the oxygenation technique, the protocol for ECT administration was similar with both techniques. SpO2 values were recorded every minute for 10 min while hemodynamic parameters were measured at 2 min and 5 min following administration of electrical stimulus. Any drop in SpO2 below 92 % was considered as a desaturation event. ResultsA total of 201 patients underwent ECTs, one each with FM and THRIVE technique.Median age of patients was 28 years. There was no difference in SpO2 between the techniques (main effect P = 0.324, interaction P = 0.14). Only one patient had desaturation with THRIVE requiring intervention with FM. None of the patients had any airway complications in terms of nasal injury, hoarseness, or pneumothorax with THRIVE. ConclusionTHRIVE is a safe alternative option for hands-free oxygenation while administering ECT. However, considering patient safety, an anaesthesiologist competent in airway management must be readily available.

Pain-related changes in crSO2 among premature infants undergoing PICC insertion

Objective To evaluate the effectiveness of cerebral regional oxygen saturation (crSO2) values, measured using near-infrared spectroscopy (NIRS), in assessing pain associated with the peripherally inserted central catheter (PICC) in premature infants. Methods NIRS was used to measure the crSO2 levels of 48 premature infants with gestational age (GA) of < 32 weeks or a birth weight of < 1500 g. Premature infant pain profile (PIPP) scores, vital signs, transcutaneous oxygen tension (TcpO2), transcutaneous carbon dioxide tension (TcpCO2), and crSO2 values were monitored. One-way repeated measure analysis of variance was used to compare heart rate (HR), respiratory rate (RR), blood pressure (BP), peripheral oxygen saturation (SpO2), TcpO2, TcpCO2, and crSO2 values before (Time 1), during (Time 2), and after (Time 3) PICC insertion. The correlation between the PIPP scores at Time 2 and the fluctuations (values detected at Time 2 minus those at Time 1) of SpO2, TcpO2, and crSO2 were also analyzed. Results The PIPP score at Time 2 was significantly higher than those at Times 1 and 3. HR, RR, and BP values increased (p < .05), and SpO2 and crSO2 levels decreased at Time 2 (p < .05) compared with those at Time 1. Stratified analysis based on GA revealed significant differences in HR, RR, and crSO2 values between Times 1 and 2 in infants with a GA of ≥ 32 weeks. In infants with a GA < 32 weeks, significant differences were observed in HR, RR, SpO2, BP, and crSO2 values between Times 1 and 2. The fluctuation of the crSO2 level was strongly correlated with the PIPP score at Time 2 (r = −0.829, p < .001). A weak correlation was observed between the PIPP score at Time 2 and TcpO2 level fluctuation (r = 0.375, p = .009). No correlation was observed between the PIPP score at Time 2 and SpO2 level fluctuation (r = 0.242, p = .097). Conclusion The fluctuation of crSO2 levels strongly correlates with PICC procedural pain. Hence, crSO2 levels measured using NIRS may be used as an indicator for pain assessment in premature infants.

PACMAN: A Framework for Pulse Oximeter Digit Detection and Reading in a Low-Resource Setting

In light of the COVID-19 pandemic, patients were required to manually input their daily oxygen saturation (SpO2) and pulse rate (PR) values into a health monitoring system—unfortunately, such a process trend to be an error in typing. Several studies attempted to detect the physiological value from the captured image using optical character recognition (OCR). However, the technology has limited availability with high cost. Thus, this study aimed to propose a novel framework called PACMAN (Pandemic Accelerated Human-Machine Collaboration) with a low-resource deep learning-based computer vision. We compared state-of-the-art object detection algorithms (scaled YOLOv4, YOLOv5, and YOLOR), including the commercial OCR tools for digit recognition on the captured images from the pulse oximeter display. All images were derived from crowdsourced data collection with varying quality and alignment. YOLOv5 was the best-performing model against the given model comparison across all datasets, notably the correctly orientated image dataset. We further improved the model performance with the digits auto-orientation algorithm and applied a clustering algorithm to extract SpO2 and PR values. The accuracy performance of YOLOv5 with the implementations was approximately 81.0-89.5%, which was enhanced compared to without any additional implementation. Accordingly, this study highlighted the completion of the PACMAN framework to detect and read digits in real-world datasets. The proposed framework has been currently integrated into the patient monitoring system utilized by hospitals nationwide.