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PloS One 2023Recovery of cognitive and physiological responses following a hypoxic exposure may not be considered in various operational and research settings. Understanding recovery...
Recovery of cognitive and physiological responses following a hypoxic exposure may not be considered in various operational and research settings. Understanding recovery profiles and influential factors can guide post-hypoxia restrictions to reduce the risk of further cognitive and physiological deterioration, and the potential for incidents and accidents. We systematically evaluated the available evidence on recovery of cognitive and basic physiological responses following an acute hypoxic exposure to improve understanding of the performance and safety implications, and to inform post-hypoxia restrictions. This systematic review summarises 30 studies that document the recovery of either a cognitive or physiological index from an acute hypoxic exposure. Titles and abstracts from PubMed (MEDLINE) and Scopus were searched from inception to July 2022, of which 22 full text articles were considered eligible. An additional 8 articles from other sources were identified and also considered eligible. The overall quality of evidence was moderate (average Rosendal score, 58%) and there was a large range of hypoxic exposures. Heart rate, peripheral blood haemoglobin-oxygen saturation and heart rate variability typically normalised within seconds-to-minutes following return to normoxia or hyperoxia. Whereas, cognitive performance, blood pressure, cerebral tissue oxygenation, ventilation and electroencephalogram indices could persist for minutes-to-hours following a hypoxic exposure, and one study suggested regional cerebral tissue oxygenation requires up to 24 hours to recover. Full recovery of most cognitive and physiological indices, however, appear much sooner and typically within ~2-4 hours. Based on these findings, there is evidence to support a 'hypoxia hangover' and a need to implement restrictions following acute hypoxic exposures. The severity and duration of these restrictions is unclear but should consider the population, subsequent requirement for safety-critical tasks and hypoxic exposure.
Topics: Humans; Hypoxia; Oximetry; Respiration; Blood Pressure; Cognition
PubMed: 37585402
DOI: 10.1371/journal.pone.0289716 -
Archives of Disease in Childhood. Fetal... Dec 2023Measuring exhaled carbon dioxide (ECO) during non-invasive ventilation at birth may provide information about lung aeration. However, the International Liaison Committee...
OBJECTIVE
Measuring exhaled carbon dioxide (ECO) during non-invasive ventilation at birth may provide information about lung aeration. However, the International Liaison Committee on Resuscitation (ILCOR) only recommends ECO detection for confirming endotracheal tube placement. ILCOR has therefore prioritised a research question that needs to be urgently evaluated: 'In newborn infants receiving intermittent positive pressure ventilation by any non-invasive interface at birth, does the use of an ECO monitor in addition to clinical assessment, pulse oximetry and/or ECG, compared with clinical assessment, pulse oximetry and/or ECG only, decrease endotracheal intubation in the delivery room, improve response to resuscitation, improve survival or reduce morbidity?'.
DESIGN
Systematic review of randomised and non-randomised studies identified by Ovid MEDLINE, Embase and Cochrane CENTRAL search until 1 August 2022.
SETTING
Delivery room.
PATIENTS
Newborn infants receiving non-invasive ventilation at birth.
INTERVENTION
ECO measurement plus routine assessment compared with routine assessment alone.
MAIN OUTCOME MEASURES
Endotracheal intubation in the delivery room, response to resuscitation, survival and morbidity.
RESULTS
Among 2370 articles, 23 were included; however, none had a relevant control group. Although studies indicated that the absence of ECO may signify airway obstruction and ECO detection may precede a heart rate increase in adequately ventilated infants, they did not directly address the research question.
CONCLUSIONS
Evidence to support the use of an ECO monitor to guide non-invasive positive pressure ventilation at birth is lacking. More research on the effectiveness of ECO measurement in addition to routine assessment during non-invasive ventilation of newborn infants at birth is needed.
PROSPERO REGISTRATION NUMBER
CRD42022344849.
Topics: Infant, Newborn; Infant; Humans; Noninvasive Ventilation; Carbon Dioxide; Respiration, Artificial; Positive-Pressure Respiration; Resuscitation; Intermittent Positive-Pressure Ventilation
PubMed: 37558397
DOI: 10.1136/archdischild-2023-325698 -
Brazilian Oral Research 2023The main purpose of this study was to answer the question: "Can radiotherapy cause changes in the dental pulp condition of patients treated with irradiation in the head...
The main purpose of this study was to answer the question: "Can radiotherapy cause changes in the dental pulp condition of patients treated with irradiation in the head and neck region?" Clinical observational studies in adults with head and neck cancer undergoing treatment with ionizing radiation, longitudinal or cross-sectional follow-up to measure oxygen saturation (SpO2), and/or pulp sensitivity test to cold stimulation, were considered eligible. A systematic literature search was performed in six different databases, including the gray literature, and in article references. Two independent evaluators selected the studies, extracted the data, recorded the data on electronic spreadsheets, and then evaluated the methodological quality using the Checklist for Quasi-Experimental Studies tool devised by JBI. The data were assessed qualitatively using the Synthesis Without Metanalysis (SWiM) guidelines. After removing the duplicate articles, carefully analyzing the titles and abstracts, and reading the papers in full, seven studies were included. Four of the studies evaluated applied the cold sensitivity test, two associated pulse oximetry and cold sensitivity, and only one used just pulse oximetry. Evaluation using the cold sensitivity test and pulse oximetry in the initial periods before radiotherapy showed a decrease in the sensitive response and in SpO2 levels during a maximum period of 1 year. However, analyses thereafter indicated a normal response in both tests from 5 to 6 years after the end of radiotherapy treatment. Radiotherapy causes changes in pulp behavior patterns in the short term; however, recovery and return to average values occurs after long periods.
Topics: Adult; Humans; Cross-Sectional Studies; Head and Neck Neoplasms; Oximetry; Dental Pulp Diseases; Radiation, Ionizing; Dental Pulp
PubMed: 37531515
DOI: 10.1590/1807-3107bor-2023.vol37.0079 -
The Cochrane Database of Systematic... Aug 2023Apnoeic oxygenation is the delivery of oxygen during the apnoeic phase preceding intubation. It is used to prevent respiratory complications of endotracheal intubation... (Review)
Review
BACKGROUND
Apnoeic oxygenation is the delivery of oxygen during the apnoeic phase preceding intubation. It is used to prevent respiratory complications of endotracheal intubation that have the potential to lead to significant adverse events including dysrhythmia, haemodynamic decompensation, hypoxic brain injury and death. Oxygen delivered by nasal cannulae during the apnoeic phase of intubation (apnoeic oxygenation) may serve as a non-invasive adjunct to endotracheal intubation to decrease the incidence of hypoxaemia, morbidity and mortality.
OBJECTIVES
To evaluate the benefits and harms of apnoeic oxygenation before intubation in adults in the prehospital, emergency department, intensive care unit and operating theatre environments compared to no apnoeic oxygenation during intubation.
SEARCH METHODS
We used standard, extensive Cochrane search methods. The latest search date was 4 November 2022.
SELECTION CRITERIA
We included randomized controlled trials (RCTs) and quasi-RCTs that compared the use of any form of apnoeic oxygenation including high flow and low flow nasal cannulae versus no apnoeic oxygenation during intubation. We defined quasi-randomization as participant allocation to each arm by means that were not truly random, such as alternation, case record number or date of birth. We excluded comparative prospective cohort and comparative retrospective cohort studies, physiological modelling studies and case reports.
DATA COLLECTION AND ANALYSIS
We used standard Cochrane methods. Our primary outcomes were 1. hospital stay and 2. incidence of severe hypoxaemia. Our secondary outcomes were 3. incidence of hypoxaemia, 4. lowest recorded saturation of pulse oximetry (SpO), 5. intensive care unit (ICU) stay, 6. first pass success rate, 7. adverse events and 8.
MORTALITY
We used GRADE to assess certainty of evidence.
MAIN RESULTS
We included 23 RCTs (2264 participants) in our analyses. Eight studies (729 participants) investigated the use of low-flow (15 L/minute or less), and 15 studies (1535 participants) investigated the use of high-flow (greater than 15 L/minute) oxygen. Settings were varied and included the emergency department (2 studies, 327 participants), ICU (7 studies, 913 participants) and operating theatre (14 studies, 1024 participants). We considered two studies to be at low risk of bias across all domains. None of the studies reported on hospital length of stay. In predominately critically ill people, there may be little to no difference in the incidence of severe hypoxaemia (SpO less than 80%) when using apnoeic oxygenation at any flow rate from the start of apnoea until successful intubation (risk ratio (RR) 0.86, 95% confidence interval (CI) 0.66 to 1.11; P = 0.25, I² = 0%; 15 studies, 1802 participants; low-certainty evidence). There was insufficient evidence of any effect on the incidence of hypoxaemia (SpO less than 93%) (RR 0.58, 95% CI 0.23 to 1.46; P = 0.25, I² = 36%; 3 studies, 489 participants; low-certainty evidence). There may be an improvement in the lowest recorded oxygen saturation, with a mean increase of 1.9% (95% CI 0.75% to 3.05%; P < 0.001, I² = 86%; 15 studies, 1525 participants; low-certainty evidence). There may be a reduction in the duration of ICU stay with the use of apnoeic oxygenation during intubation (mean difference (MD) ‒1.13 days, 95% CI ‒1.51 to ‒0.74; P < 0.0001, I² = 46%; 5 studies, 815 participants; low-certainty evidence). There may be little to no difference in first pass success rate (RR 1.00, 95% CI 0.93 to 1.08; P = 0.79, I² = 0%; 8 studies, 826 participants; moderate-certainty evidence). There may be little to no difference in incidence of adverse events including oral trauma, arrhythmia, aspiration, hypotension, pneumonia and cardiac arrest when apnoeic oxygenation is used. There was insufficient evidence about any effect on mortality (RR 0.84, 95% CI 0.70 to 1.00; P = 0.06, I² = 0%; 6 studies, 1015 participants; low-certainty evidence).
AUTHORS' CONCLUSIONS
There was some evidence that oxygenation during the apnoeic phase of intubation may improve the lowest recorded oxygen saturation. However, the differences in oxygen saturation were unlikely to be clinically significant. This did not translate into any measurable effect on the incidence of hypoxaemia or severe hypoxaemia in a group of predominately critically ill people. We were unable to assess the influence on hospital length of stay; however, there was a reduction in ICU stay in the apnoeic oxygenation group. The mechanism for this is unclear as there was little to no difference in first pass success or adverse event rates.
Topics: Adult; Humans; Apnea; Critical Illness; Critical Care; Intubation, Intratracheal; Hypoxia; Oxygen; Emergency Medical Services
PubMed: 37531462
DOI: 10.1002/14651858.CD013558.pub2 -
Critical Care (London, England) May 2023Since oxygen content and oxygen consumption typically remain unchanged within a short period, variation in central venous oxygen saturation (ΔScvO) during fluid... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Since oxygen content and oxygen consumption typically remain unchanged within a short period, variation in central venous oxygen saturation (ΔScvO) during fluid challenge can theoretically track the changes in cardiac output (CO). We conducted this meta-analysis to systematically assess the diagnostic performance of ΔScvO during a fluid challenge for fluid responsiveness in mechanically ventilated patients receiving volume expansion.
METHODS
Electronic databases were systematically searched to identify relevant studies published before October 24, 2022. As the cutoff value of ΔScvO was expected to vary across the included studies, we estimated the area under the hierarchical summary receiver operating characteristic curve (AUHSROC) as the primary measure of diagnostic accuracy. The optimal threshold of ΔScvO and the corresponding 95% confidential interval (CI) were also estimated.
RESULTS
This meta-analysis included 5 observational studies comprising 240 participants, of whom 133 (55%) were fluid responders. Overall, the ΔScvO during the fluid challenge exhibited excellent performance for defining fluid responsiveness in mechanically ventilated patients receiving volume expansion, with an AUHSROC of 0.86 (95% CI 0.83-0.89), a pooled sensitivity of 0.78 (95% CI 0.69-0.85), a pooled specificity of 0.84 (95% CI 0.72-0.91), and a pooled diagnostic odds ratio of 17.7 (95% CI 5.9-53.2). The distribution of the cutoff values was nearly conically symmetrical and concentered between 3 and 5%; the mean and median cutoff values were 4% (95% CI 3-5%) and 4% (95% CI not estimable), respectively.
CONCLUSIONS
In mechanically ventilated patients receiving volume expansion, the ΔScvO2 during the fluid challenge is a reliable indicator of fluid responsiveness. Clinical trial registration PROSPERO, https://www.crd.york.ac.uk/prospero/ , registry number: CRD42022370192.
Topics: Humans; Respiration, Artificial; Oxygen Saturation; Oximetry; Cardiac Output; ROC Curve; Fluid Therapy; Hemodynamics; Observational Studies as Topic
PubMed: 37237410
DOI: 10.1186/s13054-023-04480-z -
Respiratory Care Sep 2023The effect of application of fingernail polish on S measurement remains unclear. We conducted this systematic review to ascertain the impact of fingernail polish on S... (Review)
Review
BACKGROUND
The effect of application of fingernail polish on S measurement remains unclear. We conducted this systematic review to ascertain the impact of fingernail polish on S measurement.
METHODS
We queried PubMed, Embase, and CINAHL databases for publications indexed through December 2022. We included studies providing paired S data from fingertips without and after nail polish application or reporting the number of subjects whose S could not be measured due to fingernail polish. We used random effects modeling to summarize standardized mean differences (SMDs) and corresponding 95% CI for different nail polish colors from comparative studies.
RESULTS
We retrieved 122 studies and included 21 publications, mostly performed on healthy volunteers. Of these, 17 (81.0%) studies had a low risk of bias. We summarized mean SMD for 10 nail polish colors (black, blue, brown, green, orange, pink, purple, red, white, and yellow) from 25 paired data sets on S across 20 studies. We found small (likely clinically insignificant) but statistically significant differences in mean S when fingers were coated with black, blue, brown, or purple nail polish (SMD -0.57, -0.47, -0.33, and -0.25, respectively; 95% CI -0.86 to -0.29, -0.84 to -0.10, -0.59 to -0.07, and -0.48 to -0.02, respectively). Only one of 4 studies reported a high proportion of unsuccessful oximeter readings from fingers painted with black (88.0%) or brown (36.0%) nail polish.
CONCLUSIONS
Although fingernail polish of some colors can marginally reduce S reading or occasionally impede S measurement, the variability is clinically insignificant.
Topics: Humans; Color; Cosmetics; Nails; Oximetry; Oxygen
PubMed: 37185113
DOI: 10.4187/respcare.10399 -
European Journal of Emergency Medicine... Aug 2023Carbon monoxide (CO) poisoning is one of the most common causes of poisoning death and its diagnosis requires an elevated carboxyhemoglobin (COHb) level. Noninvasive CO... (Meta-Analysis)
Meta-Analysis
Carbon monoxide (CO) poisoning is one of the most common causes of poisoning death and its diagnosis requires an elevated carboxyhemoglobin (COHb) level. Noninvasive CO saturation by pulse oximetry (SpCO) has been available since 2005 and has the advantage of being portable and easy to use, but its accuracy in determining blood COHb level is controversial. To evaluate the accuracy of SpCO (index test) to estimate COHb (reference test). Systematic review and meta-analysis of diagnostic test accuracy (DTA) studies. Four electronic databases were searched (Medline, Embase, Cochrane Central Register of Controlled Trials, and OpenGrey) on 2 August 2022. All studies of all designs published since the 2000s evaluating the accuracy and reliability of SpCO measurement compared to blood COHb levels in human volunteers or ill patients, including children, were included. The primary outcome was to assess the diagnostic accuracy of SpCO for estimating COHb by blood sampling by modeling receiver operating characteristic (ROC) curves and calculating sensitivity and specificity (primary measures). The secondary measures were to calculate the limits of agreement (LOA) and the mean bias. This systematic review was conducted according to the Preferred Reporting Items for a Systematic Review and Meta-analysis-DTA 2018 guidelines and has been registered on International Prospective Register of Systematic Reviews (PROSPERO, CRD42020177940). The risk of bias was evaluated using the Quality Assessment of Diagnostic Accuracy Studies-2 tool. Twenty-one studies were eligible for the systematic review; 11 could be included for the quantitative analysis of the primary measures and 18 for the secondary measures. No publication bias was found. The area under the summary ROC curve was equal to 86%. The mean sensitivity and specificity were 0.77, 95% confidence interval (CI, 0.66-0.85) and 0.83, 95% CI (0.74-0.89), respectively (2089 subjects and 3381 observations). The mean bias was 0.75% and the LOA was -7.08% to 8.57%, 95% CI (-8.89 to 10.38) (2794 subjects and 4646 observations). Noninvasive measurement of COHb (SpCO) using current pulse CO oximeters do not seem to be highly accurate to estimate blood COHb (moderate sensitivity and specificity, large LOA). They should probably not be used to confirm (rule-in) or exclude (rule-out) CO poisoning with certainty.
Topics: Child; Humans; Carboxyhemoglobin; Reproducibility of Results; Oximetry; Carbon Monoxide Poisoning; Diagnostic Tests, Routine
PubMed: 37171830
DOI: 10.1097/MEJ.0000000000001043 -
ERJ Open Research Mar 2023Our aim was to investigate the effectiveness of virtual wards on health outcomes in patients with acute respiratory infection. (Review)
Review
Impact of remote vital sign monitoring on health outcomes in acute respiratory infection and exacerbation of chronic respiratory conditions: systematic review and meta-analysis.
BACKGROUND
Our aim was to investigate the effectiveness of virtual wards on health outcomes in patients with acute respiratory infection.
METHODS
We searched four electronic databases from January 2000 to March 2021 for randomised controlled trials (RCTs). We included studies in people with acute respiratory illness or an acute exacerbation of a chronic respiratory illness, where a patient or carer measured vital signs (oximetry, blood pressure, pulse) for initial diagnosis and/or asynchronous monitoring, in a person living in private housing or a care home. We performed random-effects meta-analysis for mortality.
RESULTS
We reviewed 5834 abstracts and 107 full texts. Nine RCTs were judged to be relevant for inclusion, in which sample sizes ranged from 37 to 389 (total n=1627) and mean ages ranged between 61 and 77 years. Five were judged to be at low risk of bias. Five RCTs had fewer hospital admissions in the intervention (monitoring) group, out of which two studies reported a significant difference. Two studies reported more admissions in the intervention group, with one reporting a significant difference. We were unable to perform a meta-analysis on healthcare utilisation and hospitalisation data due to lack of outcome definition in the primary studies and variable outcome measurements. We judged two studies to be at low risk of bias. The pooled summary risk ratio for mortality was 0.90 (95% CI 0.55-1.48).
CONCLUSION
The limited literature for remote monitoring of vital signs in acute respiratory illness provides weak evidence that these interventions have a variable impact on hospitalisations and healthcare utilisation, and may reduce mortality.
PubMed: 37101740
DOI: 10.1183/23120541.00393-2022 -
Cureus Feb 2023The purpose of this review is to summarize the research on the accuracy of oxygen saturation (spO) measurements using the Apple Watch (Apple Inc., Cupertino,... (Review)
Review
The purpose of this review is to summarize the research on the accuracy of oxygen saturation (spO) measurements using the Apple Watch (Apple Inc., Cupertino, California). The Medline and Google Scholar databases were searched for papers evaluating the spO measurements of the Apple Watch vs. any kind of ground truth and records were analyzed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The five publications with 973 total patients that met the inclusion criteria all used the Apple Watch Series 6 and described 95% limits of agreement of +/- 2.7 to 5.9% spO. However, outliers of up to 15% spO were reported. Only one study had patient-level data uploaded to a public repository. The Apple Watch Series 6 does not show a strong systematic bias compared to conventional, medical-grade pulse oximeters. However, outliers do occur and should not cause concern in otherwise healthy individuals. The impact of race on measurement accuracy should be investigated.
PubMed: 36974257
DOI: 10.7759/cureus.35355 -
JAMA Network Open Mar 2023High-dose docosahexaenoic acid (DHA), a long-chain polyunsaturated fatty acid, may affect the risk of bronchopulmonary dysplasia (BPD). However, high-level summative... (Meta-Analysis)
Meta-Analysis
Association Between Enteral Supplementation With High-Dose Docosahexaenoic Acid and Risk of Bronchopulmonary Dysplasia in Preterm Infants: A Systematic Review and Meta-analysis.
IMPORTANCE
High-dose docosahexaenoic acid (DHA), a long-chain polyunsaturated fatty acid, may affect the risk of bronchopulmonary dysplasia (BPD). However, high-level summative evidence supporting such clinical association in very preterm infants is lacking.
OBJECTIVE
To examine the association between enteral supplementation with high-dose DHA during the neonatal period and the risk of BPD in preterm infants born at less than 29 weeks' gestation.
DATA SOURCES
PubMed, Embase, Web of Science, Cochrane Central Register of Controlled Trials, medRxiv, and ClinicalTrials.gov were searched from inception to August 1, 2022, for eligible articles with no language restrictions.
STUDY SELECTION
Randomized clinical trials (RCTs) were eligible for inclusion (1) if their interventions involved direct administration of a minimum DHA supplementation of 40 mg/kg/d or breast milk or formula feeding of at least 0.4% of total fatty acids, and (2) if they reported data on either BPD, death, BPD severity, or a combined outcome of BPD and death.
DATA EXTRACTION AND SYNTHESIS
Two investigators completed independent review of titles and abstracts, full text screening, data extraction, and quality assessment using the Cochrane Risk of Bias 2.0. Risk ratios (RRs) with 95% CIs were pooled using random-effect meta-analyses.
MAIN OUTCOMES AND MEASURES
Primary outcome was BPD using trial-specific definitions, which was further stratified for RCTs that used a more stringent BPD definition based on systematic pulse oximetry assessment at 36 weeks' postmenstrual age. Other outcomes were BPD, death, BPD severity, or combined BPD and death.
RESULTS
Among the 2760 studies screened, 4 RCTs were included, which involved 2304 infants (1223 boys [53.1%]; mean [SD] gestational age, 26.5 [1.6] weeks). Enteral supplementation with high-dose DHA was associated with neither BPD (4 studies [n = 2186 infants]; RR, 1.07 [95% CI, 0.86-1.34]; P = .53; I2 = 72%) nor BPD or death (4 studies [n = 2299 infants]; RR, 1.04 [95% CI, 0.91-1.18]; P = .59; I2 = 61%). However, an inverse association with BPD was found in RCTs that used a more stringent BPD definition (2 studies [n = 1686 infants]; RR, 1.20 [95% CI, 1.01-1.42]; P = .04; I2 = 48%). Additionally, DHA was inversely associated with moderate-to-severe BPD (3 studies [n = 1892 infants]; RR, 1.16 [95% CI, 1.04-1.29]; P = .008; I2 = 0%).
CONCLUSIONS AND RELEVANCE
Results of this study showed that enteral supplementation with high-dose DHA in the neonatal period was not associated overall with BPD, but an inverse association was found in the included RCTs that used a more stringent BPD definition. These findings suggest that high-dose DHA supplementation should not be recommended to prevent BPD in very preterm infants.
Topics: Infant, Newborn; Infant; Male; Female; Humans; Adult; Docosahexaenoic Acids; Bronchopulmonary Dysplasia; Infant, Premature; Gestational Age; Infant, Premature, Diseases; Fetal Growth Retardation; Dietary Supplements
PubMed: 36943265
DOI: 10.1001/jamanetworkopen.2023.3934