Oxygen Saturation in Neonate after Birth

Background: Oxygen saturation measures the quantity of haemoglobin in the blood that is saturated with oxygen. Hemoglobin is a component of red blood cells that binds oxygen and transports it to outlying tissues. Oxygen is commonly used throughout the world in neonatal units. Injudicious use of Oxygen may not maintain appropriate oxygen status rather can lead to hypoxemia or hyperoxemia, both of the conditions are injurious to neonatal health. Objective: To assess the oxygen saturation in neonate after birth.Methods:A cross-sectional study conducted in the Department of Neonatology BSMMU, Shahbag, Dhaka, Lab Aid Specialized Hospital, Dhaka, Bangladesh from October 2013 to March 2014. A total 317 patients were selected according to selection criteria. The parents were interviewed with a specific pre-designed and pre-tested questionnaire and some information were gathered by document review. All neonate both term and late preterm (˃34weeks) who would not be anticipated for resuscitation was included.Results:A total 317 neonate were selected according to selection criteria. Among the study subjects more than half were male (57.1%). Rests were female (42.9%). Average gestational age of the study subjects was 37.47± 1.16 (SD) with the range of 34-40. On the other hand average birth weight was 2.88±0.46 (SD) with the minimum birth weight 2.0 kg and maximum weight 4.2 kg. Illustrates the median (IQR) heart rate from one to ten min for preterm versus term births. At one to three minutes and at five minutes after birth preterm infants had significantly lower SpO2 measurements. From six to 10 minutes after birth and four minutes after birth there was no significant difference between SpO2 measurements for mode of delivery. Paired sample t test showed that average SpO2 was less in 1 minute[88.42±4.8(SD)] than in 5 minute [94.25±3.5(SD)] and statistically this differences were highly significant (t=24.44, p=0.000). Pearson correlation showed high positive correlation (p=0.000) and correlation co-efficient r=0.479. Correlation was significant at the 0.01 level.Conclusion:It is “normal” to have low oxygen saturation measurements in the first minutes after birth. It takes time for infants to reach oxygen saturation levels described as “normal” in the later postnatal period. Oxygen saturation increased with time i.e., it was more in 5 minutes than in 1 minute and similarly more in 10 minutes than in 5 minutes. Conversely heart rate was found more in one minute than to five and ten minutes. Oxygen saturation was ≥ 90% within 3 to 4 minutes. Significant changes were found in Oxygen saturation by mode of delivery in three minutes & in heart rate by two minutes after birth. At one to ten minutes after birth preterm infants had lower SpO2 measurements.

Inadvertent severe hypercapnia during general anesthesia: drop-in oxygen saturation or electrocardiography changes; which one warns us earlier?

Background During general anesthesia especially when the nurse or anesthesiologist forgets to change manual to controlled mode after successful endotracheal intubation, capnography shows End-tidal Co2 above 20 mmHg after checking the place of the tracheal tube and will remain on the screen permanently. In this scenario, the patient receives a high concentration of oxygen, and Spo2 (oxygen saturation) does not drop for a long time which is too late to intervene. It has been all-time questionable which one of the cardiac dysrhythmias or Spo2 dropping occurs earlier. Results Medical records of seven deceased patients reviewed. All of them had electrocardiogram changes including premature ventricular contraction or bradycardia as a first warning sign. Oxygen saturation remains above 95% even with cardiac dysrhythmia. Conclusions Bradycardia and premature ventricular contraction were the first warning findings for severe hypercapnia during general anesthesia and occurred earlier than dropping oxygen saturation. Furthermore, the normal capnography waveform is more reliable than the End-tidal Co2 number for monitoring.

Ratio of Mixed Venous Oxygen Saturation-to-Pulmonary Capillary Wedge Pressure: Insights From the Veterans Affairs Clinical Assessment, Reporting, and Tracking Program

Background: Hemodynamic values from right heart catheterization aid diagnosis and clinical decision-making but may not predict outcomes. Mixed venous oxygen saturation percentage and pulmonary capillary wedge pressure relate to cardiac output and congestion, respectively. We theorized that a novel, simple ratio of these measurements could estimate cardiovascular prognosis. Methods: We queried Veterans Affairs’ databases for clinical, hemodynamic, and outcome data. Using the index right heart catheterization between 2010 and 2016, we calculated the ratio of mixed venous oxygen saturation-to-pulmonary capillary wedge pressure, termed ratio of saturation-to-wedge (RSW). The primary outcome was time to all-cause mortality; secondary outcome was 1-year urgent heart failure presentation. Patients were stratified into quartiles of RSW, Fick cardiac index (CI), thermodilution CI, and pulmonary capillary wedge pressure alone. Kaplan-Meier curves and Cox proportional hazards models related comparators with outcomes. Results: Of 12 019 patients meeting inclusion criteria, 9826 had values to calculate RSW (median 4.00, interquartile range, 2.67–6.05). Kaplan-Meier curves showed early, sustained separation by RSW strata. Cox modeling estimated that increasing RSW by 50% decreases mortality hazard by 19% (estimated hazard ratio, 0.81 [95% CI, 0.79–0.83], P <0.001) and secondary outcome hazard by 28% (hazard ratio, 0.72 [95% CI, 0.70–0.74], P <0.001). Among the 3793 patients with data for all comparators, Cox models showed RSW best associated with outcomes (by both C statistics and Bayes factors). Furthermore, pulmonary capillary wedge pressure was superior to thermodilution CI and Fick CI. Multivariable adjustment attenuated without eliminating the association of RSW with outcomes. Conclusions: In a large national database, RSW was superior to conventional right heart catheterization indices at assessing risk of mortality and urgent heart failure presentation. This simple calculation with routine data may contribute to clinical decision-making in this population.

COVID-19 symptoms reduce with targeted hydration of the nose, larynx and trachea

Dirty air and poor access to healthcare threatens the lives of billions of people in low-income regions of the world. We investigated whether upper-airway hydration might alter two-phase flow in the airways on normal tidal breathing and be a useful, safe, easily distributed non-drug intervention for limiting risks of COVID-19. In observational human volunteer studies involving 464 human subjects in Marburg, Germany (357 normal subjects), Boston, US (20 healthy subjects), and Bangalore, India (87 subjects recently tested positive for COVID-19), we find that respiratory droplet generation increases by up to 4 orders of magnitude with up to 1% total body mass dehydration (n=20), and in dehydration-associated states of advanced age (n=357), elevated BMI-age (n=148), and SARS-CoV-2 infection (n=87). Hydration of the nose, larynx and trachea in a protocol of exercise-induced dehydration by the nasal inhalation of calcium-rich hypertonic salt droplets of mean diameter 8-12 µm diminished respiratory droplet numbers and increased oxygenation relative to a non-treatment control (P<0.05). In a randomized double-blinded nasal-saline control study, thrice-a-day delivery of the calcium-rich hypertonic salts (active) over three days suppressed respiratory droplet generation by 51% +/- 11% and increased oxygen saturation by 48.08% ± 9.61% (P<0.001) in COVID-19 positive subjects (n=20), while no changes in exhaled aerosol (P=0.235) or oxygen saturation (P=0.533) were observed in the nasal-saline control group (n=20). In the active group 47% of patients discharged with no self-reported symptoms while all of the subjects in the nasal saline group discharged with lingering symptoms. Hydration of the upper airways appears promising as a non-drug approach for reducing risks of lower respiratory-tract infections such as COVID-19.

Oxygen saturation and heart rate in healthy term and late preterm infants with delayed cord clamping

Blood oxygen in the fetus is substantially lower than in the newborn infant. In the minutes after birth, arterial oxygen saturation rises from around 50–60% to 90–95%. Initial respiratory efforts generate negative trans-thoracic pressures that drive liquid from the airways into the lung interstitium facilitating lung aeration, blood oxygenation, and pulmonary artery vasodilatation. Consequently, intra- (foramen ovale) and extra-cardiac (ductus arteriosus) shunting changes and the sequential circulation switches to a parallel pulmonary and systemic circulation. Delaying cord clamping preserves blood flow through the ascending vena cava, thus increasing right and left ventricular preload. Recently published reference ranges have suggested that delayed cord clamping positively influenced the fetal-to-neonatal transition. Oxygen saturation in babies with delayed cord clamping plateaus significantly earlier to values of 85–90% than in babies with immediate cord clamping. Delayed cord clamping may also contribute to fewer episodes of brady-or-tachycardia in the first minutes after birth, but data from randomized trials are awaited. Impact Delaying cord clamping during fetal to neonatal transition contributes to a significantly earlier plateauing of oxygen saturation and fewer episodes of brady-and/or-tachycardia in the first minutes after birth. We provide updated information regarding the changes in SpO2 and HR during postnatal adaptation of term and late preterm infants receiving delayed compared with immediate cord clamping. Nomograms in newborn infants with delayed cord clamping will provide valuable reference ranges to establish target SpO2 and HR in the first minutes after birth.

Assessment of Dental Anxiety and Hemodynamic Changes during Different Dental Procedures: A Report from Eastern Saudi Arabia

Objectives This study aimed to investigate hemodynamic changes in healthy adult patients during different dental procedures and evaluate whether these changes were associated with patients' dental anxiety. Materials and Methods A convenience sample of 119 patients of both genders undergoing routine dental care participated in the study. Participants responded to the Arabic version of the modified dental anxiety scale (MDAS) and a self-structured questionnaire. Each patient had their blood pressure, heart rate, and oxygen saturation measured at three points: before, during, and after the dental procedure using an electronic sphygmomanometer. MDAS scores were categorized into no anxiety, mild, moderate or severe anxiety, while readings of heart rate and blood pressure were categorized into no change, increased or decreased and either “no change” or “increased” for oxygen saturation. Chi-square test was used to investigate the association between the study variables and a p value of < 0.05 was considered statistically significant. SPSS version 20 was used in the analysis. Results Mean ( ± standard deviation [SD]) of MDAS was 11.12 ( ± 3.9) an indicative of moderate dental anxiety. No changes in blood pressure, heart rate, or in oxygen saturation were observed on 39.5%, 54.6% and 97.5% among the study participants, respectively. Half of the participants avoided dental care, with dental anxiety being the main reason for that (26.1%). Pattern of dental visits was significantly associated with MDAS scores (p = 0.042). There were significant changes in blood pressure (p = 0.0003), heart rate (p = 0.01) but not in oxygen saturation (p = 0.33). Changes in blood pressure, heart rate, and oxygen saturation were not associated with dental anxiety p = 0.15, 0.10, and 0.99, respectively. Conclusion The results of this study indicate that the type of dental procedure may cause dental anxiety and cause hemodynamic changes. Therefore, close monitoring of patients with dental anxiety during the treatment is advised.