Arterial Blood pH Research Articles

Working-hour phenomenon in obstetrics is an attainable target to improve neonatal outcomes

Giving birth in a health care facility does not guarantee high-quality care or favorable outcomes. The working-hour phenomenon describes adverse outcomes of institutional births outside regular working hours. The objectives of the study were to evaluate whether the time of birth is associated with adverse neonatal outcomes and to identify the riskiest time periods for obstetrical care. This nationwide retrospective cohort study analyzed data from 2008 to 2016 from all 82 obstetric departments in Austria. Births at ≥ 23+0 gestational weeks with ≥500 g birthweight were included. Independent variables were categorized by the time of day vs night as core time (morning, day) and off hours (evening, nighttime periods 1-4). The composite primary outcome was adverse neonatal outcome, defined as arterial umbilical cord blood pH <7.2, 5 minute Apgar score <7, and/or admission to the neonatal intensive care unit. Multivariate logistic regression was used to develop a model to predict these adverse neonatal outcomes. Of 462,947 births, 227,672 (49.2%) occurred during off hours and had a comparable distribution in all maternity units, regardless of volume (<500 births per year: 50.3% during core time vs 49.7% during off hours; ≥500 births per year: 50.7% core time vs 49.3% off hours; perinatal tertiary center: 51.2% core time vs 48.8% off hours). Furthermore, most women (35.8-35.9%) gave birth between 2:00 and 5:59 am (night periods 3 and 4). After adjustment for covariates, we found that adverse neonatal outcomes also occurred more frequently during these night periods 3 and 4, in addition to the early morning period (night 3: odds ratio, 1.05; 95% confidence interval, 1.03-1.08; P < .001; night 4: odds ratio, 1.08; 95% confidence interval, 1.05-1.10; P < .001; early morning period: odds ratio, 1.05; 95% confidence interval, 1.02-1.08; P < .001). The adjusted odds for adverse outcomes were lowest for births between 6:00 and 7:59 pm (odds ratio, 0.96; 95% confidence interval, 0.93-0.99; P= .006). There is an increased risk of adverse neonatal outcomes when giving birth between 2:00 and 7:59 am. The so-called working-hour phenomenon is an attainable target to improve neonatal outcomes. Health care providers should ensure an optimal organizational framework during this time period.

High Fructose Consumption during Pregnancy and Lactation Leads to Maternal Renal Function Alteration

The consumption of foods that have fructose in its formulations has grown in the last decades. Nevertheless, increased consumption of this sugar has been related to the development of diseases such as obesity, diabetes and others. Many physiological changes occur during pregnancy and lactation and high consumption of fructose in these periods can interfere with maternal health. Thus, this study aims to evaluate the effects of increased fructose consumption on gestation and lactation on blood pressure and renal function.MethodsFemales Wistar rats were randomly assigned to groups: Control (C) and Fructose (F). The group C received food and drinking water ad libitum, and F received food and D‐fructose solution (20%) for drinking ad libitum. In F, the offer of D‐fructose solution begun 1week before mating and continued during pregnancy and lactation. Renal function was evaluated 21 days after offspring birth. Indirect measurement of systolic blood pressure (BPi), body weight, arterial blood pH, glycemia, ureia concentration in plasma, glomerular filtration rate ‐ GFR (creatinine clearance), excreted load of sodium (ENa+) and potassium (EK+) were measured. Ethic Committee on Animal Use of the Federal University of Sao Paulo approval number 757270117.ResultsCompared with C group, F presented higher values of BPi (129.7±1.4 vs 118.4±1.9 mmHg; p=0.0012), body weight (281.7±4.9 vs 232.7± 22.9 g; p=0.0245) and urinary flow (33.4±3.6 vs 14.6±2.1 mL; p=0.0035). F also had decreased GFR (3.8±0.4 vs 6.0± 0.5 mL/min/kg; p=0.0082), ENa+ (0.88±0.12 vs 1.42±0.25 mEq/24h; p=0.0350) and EK+ (2.24±0.38 vs 3.73±0.51 mEq/24h, p=0.0350). There were no significant differences between the groups regarding the arterial blood pH (7.40±0.01 vs 7.39±0.02; p=0.7599), glycemia (160.7± 3.5 vs 146.7±4.7 mg/dL; p=0.0565) and ureia concentration in plasma (36.7±1.2 vs 34.9±1.1 mg/dL; p=0.4645). Values presented as mean ± sem, Mann‐Whitney test, p ≤ 0.05; number of animals: C=6, F=7.ConclusionsThe results suggest that in rats, fructose overload during pregnancy and lactation can lead to maternal renal dysfunction (reduced GFR and sodium excretion), changes probably related to the increase in blood pressure observed in these animals.Support or Funding InformationFAPESP, CNPqThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Neonatal arterial blood gases &amp; immediate outcome following perinatal asphyxia.

Background: Perinatal asphyxia (PNA) remains a significant cause of death and disability despite the important advances in perinatal care in the past decades. Early neonatal mortality within the first 24 hours contributes substantially to overall neonatal mortality rates. Estimates of the incidence of perinatal asphyxia vary, in resource-rich countries is about 1/1000 live births and in resource-poor countries is probably much more common, an incidence of 5–10/1000 live births and represents the second most common cause of neonatal death (24%) after preterm birth related complications (35%). About one quarter of all neonatal deaths globally are caused by PNA &amp; an equal number of serious neurological consequences ranging from cerebral palsy &amp; mental retardation to epilepsy.&#x0D; Objective: To determine how well neonatal arterial blood pH and base deficit predict immediate outcome (survival to discharge) following perinatal asphyxia.&#x0D; Methods: This was a prospective study conducted in the delivery room and adjacent neonatal area (NICU) of Ad-din Medical College Hospital (AMCH), over 6 months from 1st June and 30th November, 2017. Research assistants were trained to observe and record events related to labor and neonatal resuscitation. Patient information was obtained which included patient characteristics (gender, birth weight &amp; gestational age) and APGAR scores at and beyond 5 minutes. Within one hour of delivery all admitted neonates were subjected to an arterial blood gas (ABG) analysis by GEM Premier 3000 blood gas analyzer and pH and base deficit were noted. All the neonates were classified according to GA, BW and Gender. After proper cleaning the collected data were analyzed thoroughly. Descriptive analyses were performed; differences in outcome by GA, BW, Gender, APGAR scores and ABG (pH and base deficit) status were determined using analysis of variance. Analyses were performed using the Statistical Package for Social Sciences (SPSS) version (Chi-Square test).&#x0D; Results: A total 50 neonates were studied in this period of which 72% survived &amp; 28 % expired. Death was mostly observed in neonate who had very high level of base deficit (&gt; 20mmol/L) &amp; very low pH (pH &lt;7.0) in 1st hour postnatal ABG. Survival rate was higher, 94.7% in &gt;35 - &lt;37 weeks GA group in comparison of &gt;37 weeks (58%) of GA (p = 0.0050). The neonates with birth weight (BW ) &gt;2000 - &lt;2500 gm were observed 77.78% survival and 68.75% in neonates with BW &gt;2500gm (p = 0.494). In this study most of the neonates were male (70%) &amp; recovery rate was relatively better among baby boys (74.3%) than baby girls (66.67%) (p = 0.582). High APGAR score neonates had better rate of recovery than poor APGAR score neonates. The neonates with APGAR score 4-6 beyond 5 minutes were observed 88.33% survival &amp; the neonates with APGAR score 0-3 beyond 5minutes were 55% survival (p= 0.028). High pH value neonates in 1st hour ABG were found higher rate of survival in comparison to low pH value neonates. It was 83.33% in pH 7.10- &lt;7.20 neonates, 72.73% in pH 7.0- &lt;7.10 neonates and 33.33% in pH &lt;7.0 neonates respectively (p=0.0136). The neonates with high level of base deficit in 1st hour ABG showed lower rate of survival than low level of base deficit neonates. It was 12.5% in base deficit &gt; 20mmol/L neonates, 33.33% in base deficit &gt; 15 - 20mmol/L neonates &amp; 87.18% in base deficit &gt; 12 -15mmol/L neonates respectively (p=0.00003).&#x0D; Conclusion: From this study it is concluded that initial pH and base deficit of 1st hour ABG of neonates along with APGAR score at or beyond 5 minutes is a good predictor of risk &amp; immediate outcome following perinatal asphyxia. A good percentage of neonates recover due to early diagnosis, meticulous nursing care and timely intervention.&#x0D; Bangladesh Journal of Medical Science Vol.18(2) 2019 p.238-243

Impact of intertwin interval on short-term neonatal outcomesof the second twin in dichorionic pregnancies withvaginal delivery.

To examine the effect of intertwin interval on umbilical cord pH and Apgar scores of the second twin after vaginal delivery. A retrospective study of twin deliveries at a university hospital in Spain between August 2012 and September 2017. Inclusion criteria were vaginal delivery of both twins at 32 gestational weeks or more. Exclusion criteria were monochorionic pregnancies and indication for cesarean delivery. The sample was dichotomized by intertwin interval (<10 and ≥10minutes). Neonatal outcomes including Apgar scores and umbilical cord pH were evaluated. Overall, 323 twin deliveries were included. Intertwin interval was less than 10minutes in 277 (85.6%) cases, and 10minutes or longer in 46 (14.2%). There were no differences in maternal or obstetric characteristics between the groups. Incidence of instrumental delivery (P<0.001) and internal podalic version (P<0.001) for the second twin was higher in the longer interval group. A longer interval was associated with higher frequencies of 1-minute Apgar score below 4 (P=0.009), 5-minute Apgar score below 7 (P<0.001), and umbilical cord pH below 7.15 (P<0.001). Second twins with an intertwin interval of 10minutes or longer are more likely to have poorer Apgar scores and arterial blood pH below 7.15.

Prediction of adverse perinatal outcome by cerebroplacental ratio in women undergoing induction of labor.

To investigate the performance of screening for adverse perinatal outcome by the cerebroplacental ratio (CPR) measured within 24 h prior to induction of labor. This was a prospective observational study of 1902 singleton pregnancies undergoing induction of labor at ≥ 37 weeks' gestation. Doppler ultrasound was used to measure the pulsatility index (PI) in the umbilical artery (UA) and fetal middle cerebral artery (MCA) within 24 h before induction of labor. The measured UA-PI and MCA-PI and their ratio were converted to multiples of the median after adjustment for gestational age. Univariable and multivariable logistic regression analysis was used to determine whether CPR improved the prediction of adverse perinatal outcome provided by maternal characteristics, medical history and obstetric factors. The detection rate (DR) and false-positive rate (FPR) of screening by CPR were estimated for Cesarean section for presumed fetal distress and adverse neonatal outcome, which included umbilical arterial or venous cord blood pH ≤ 7 and ≤ 7.1, respectively, 5-min Apgar score < 7, admission to the neonatal intensive care unit for > 24 h or hypoxic ischemic encephalopathy. A combination of maternal and pregnancy characteristics, including age, weight, racial origin, previous obstetric history, pre-eclampsia, gestational age at delivery and amniotic fluid volume, identified 39% of pregnancies requiring Cesarean section for fetal distress at a FPR of 10%; addition of CPR did not improve the performance of screening. In screening for adverse neonatal outcome by a combination of parity and CPR, the DR was 17% at a FPR of 10%. Low CPR, measured within 24 h prior to induction of labor, is associated with increased risk of Cesarean section for fetal distress and adverse neonatal outcome, but the performance of CPR for such surrogate measures of fetal hypoxic morbidity is poor. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Clarifying the Confusion of Arterial Blood Gas Analysis: Is it Compensation or Combination?

Arterial blood gas (ABG) analysis assesses the adequacy of ventilation, oxygenation, and the acid-base status of the body by measuring the levels of pH, oxygen, carbon dioxide, and bicarbonate in arterial blood. Interpretation of ABG results, which can play a major role in diagnosis and treatment of patients with pulmonary and other critical conditions, can sometimes be difficult. This article focuses on basic ABG analysis and interpretation, discusses the combinations of imbalances that may occur, and reviews the compensatory mechanisms that arise as a result.

Postnatal condition of the second twin in respect to mode of delivery, chorionicity and type of fetal growth.

The increased use of assisted reproductive techniques (ART) contributes to the increased rate of twin pregnancies, which are burdened with a higher risk of complications. Factors that affect the condition of the second twin are understudied. The objective of this study was to assess the impact of the delivery mode, chorionicity, amnionicity, and the type of fetal growth on the postnatal condition of the second twin. The study included data from 475 pregnant women with twin pregnancies. Maternal age, parity, chorionicity, amnionicity, type of fetal growth, mode of delivery, gestational weeks at delivery, Apgar score, and umbilical arterial blood pH were retrospectively analyzed. Data normality was checked with the Kolmogorov-Smirnov test. The paired Wilcoxon signed-rank test and χ2 test were used for comparisons between groups. To check predictive value of the analyzed variables multiple linear regression was used. The mean maternal age was 29.22 (standard deviation (SD) ±5.19) years. The maternal age and gestational age at delivery did not differ significantly between women who delivered by cesarean section (CS) and vaginal delivery (VD). In the second twin, the Apgar score and values of arterial umbilical blood pH were lower in infants delivered by VD than in those delivered by CS (6.30 ±2.83 and 7.30 ±0.12; p = 0.0209 and 7.26 ±0.12 and 7.30 ±0.11; p = 0.0236, respectively). In monochorionic diamniotic twins with asymmetric growth, the second twin achieved significantly lower outcome than the first twin. Vaginal delivery was a predictive factor for a lower Apgar score and lower values of umbilical arterial blood pH in second twins, while not in first twins. Symmetrical fetal growth of twins was a predictive factor for better postnatal condition for both twins. In twin pregnancies, VD, but not CS, is associated with increased risk of worse postnatal condition of the second twin. In monochorionic diamniotic pregnancies complicated by growth discordance, CS seems to be a reasonable mode of delivery.

Postnatal outcomes in lambs exposed antenatally and acutely postnatally to fluoxetine.

Approximately 1/3 of newborns exposed antenatally to selective serotonin reuptake inhibitors (SSRIs) exhibit poor neonatal adaptation. Although several potential mechanisms have been proposed, the actual mechanism has not been elucidated. We investigated outcomes in neonatal lambs exposed prenatally or postnatally to fluoxetine (FX). Daily FX injections (50 mg) were given intravenously (i.v.) to five pregnant ewes via implanted catheters beginning at 131-132 days gestation (term = 147 days) for 2 weeks. In another group, lambs with implanted vascular catheters had sterile water (n = 9) or FX (1 mg/kg, n = 12) injected i.v. on ~postnatal day (PND) 4. Prenatal FX-exposed lambs (n = 7) were hyperactive during PND 4 to 14 and their heart rate variability (HRV) was significantly lower than in control lambs (n = 7) on PND 2. In contrast, arterial pressure, heart rate, electrocardiogram, arterial blood gases, pH, glucose, lactate, cortisol, and sleep-activity cycles were not altered following postnatal FX injection. This abnormal postnatal hyperactivity with antenatal FX exposure may reflect increased maturity in terms of locomotory activity. The results suggest that altered brain development may be involved in the poor neonatal adaptation in human infants exposed to FX in utero.

Effects of pH alteration on the pathogenesis of medication-related osteonecrosis of the jaw.

An acidic environment has been recognized to increase catabolic activities and inhibit osteoblastic deposition, and also exhibited in the pathogenesis of various bone diseases. The aim of the study was to investigate the role of systemic and local pH alteration in the pathogenesis of medication-related osteonecrosis of the jaw (MRONJ). Initially, MRONJ was induced in 54 Sprague-Dawley rats via subcutaneous bisphosphonate injections, once a week for 8 weeks. A week prior to bisphosphonate termination, surgical intervention was performed and rats were divided into 3 groups-alkalotic, acidic and control group, wherein each received NaHCO3, NH4Cl and normal saline, respectively for 8 weeks. Upon sacrifice, blood was sent for arterial blood pH analysis and their mandibles were subjected to histomorphometric and μCT analyses. ONJ was histologically defined as necrotic bone persisting for eight weeks after surgical intervention. Each intervention exemplified its expected outcome wherein each group exhibited a borderline alkalotic (7.43 ± 0.05) and acidic state (7.27 ± 37), respectively (P < 0.05). Acidic group showed a higher occurrence of MRONJ (95%) compared to that of alkalotic group (60%) and control (76.9%). Histomorphometric and microstructural evaluation revealed that acidic group presented deteriorated bone architectures with significantly higher necrotic bone fraction, clusters of empty lacunae, N.Oc/B.Pm and lower B.Ar./T.Ar, BV/TV, Tb.Th (P < 0.05). Alkalotic group showed possible protective effects against ONJ versus acidic group, however these trends were not statistically significant. An acidic milieu aggravated ONJ development in an animal model. Further investigations are needed to elucidate the exact role of acid-base balance in MRONJ pathogenesis and possible benefits of alkali supplementation for the prevention.

Blood gas analysis in pigs submitted to different concentrations of nitrous oxide or oxygen, under different ventilatory modalities

ABSTRACT The effects of different concentrations of oxygen and nitrous oxide on blood gas parameters in pigs maintained under spontaneous or pressure-controlled ventilation, with or without positive end-expiratory pressure (PEEP), were compared. Forty-eight pigs were randomly divided into six groups, submitted to different concentrations of compressed air or N2O, associated with different fractions of inspired oxygen (FiO2). The group subject to 30% of compressed air (GA30) showed the closest proximity to the physiological range of partial pressure (PaO2) expected for the species. For oxygen saturation (SaO2), the values obtained were below the lower physiological limit in the group administered 30% N2O (GN30). Use of PEEP positively interfered in PaCO2 independent of FiO2, however, its effectiveness can be compromised when complemented by N2O-based anesthesia. For SaO2, only GN30 showed values lower than adequate for maintaining tissue oxygenation. The pH, base deficit and bicarbonate in arterial blood were influenced by FiO2 and N2O. In conclusion, the use of compressed air maintains blood gas parameters at their most stable, especially GA30 and PEEP, which seemed to positively influence the experimental groups, with some interference from FiO2 and N2O.

Requirement and Duration of Tube Feed Supplementation among Congenital Diaphragmatic Hernia Patients

PurposeOral feeds pose a challenge for congenital diaphragmatic hernia (CDH) infants. Tube feed (TF) supplementation may be required to support the achievement of normal growth. The aim of this study was to determine the duration and factors associated with TF use in CDH infants at our institution. MethodsA single centre retrospective chart review was performed for CDH-born infants who underwent repair between 2000 to 2013 (REB #1000053124). Patient demographics, perinatal management, and feeding status of infants with at least 1-year follow-up were reviewed. ResultsOf 160 CDH infants, 32 (20%) were discharged on partial or complete TF, and an additional 5 (3.1%) patients started TF post discharge. CDH infants with TF were more likely to have initial arterial blood pH < 7.25, patch repair, ECMO support, and prolonged ICU stay (p < 0.05). Time to TF discontinuation did not differ significantly between those partially or fully TF at discharge. Twelve patients (33.3%) remained TF at their last known follow-up. ConclusionHigh risk CDH patients are likely to require TF to support their nutritional intake. Parents and caregivers need to be informed and properly supported. Long-term monitoring of CDH patient oral intake, growth, and development will be required. Level of Evidence/Type of StudyLevel III Retrospective Study.

Cardiotocography alone vs. cardiotocography with ST segment analysis for intrapartum fetal monitoring in women with late-term pregnancy. A randomized controlled trial

ObjectivesRandomized studies have obtained conflicting results regarding the usefulness of fetal electrocardiographic (ECG) ST-segment analysis, possibly because these studies included non-homogeneous populations. We designed a study to determine whether this monitoring technique is potentially useful for populations at risk for fetal heart rate alterations during labor, i.e. groups of women who share late-term pregnancy as a risk factor. Study designThis randomized clinical trial recruited women whose pregnancy had lasted more than 290 days. The participants were randomly assigned to continuous fetal cardiotocographic monitoring alone (CTG group) or with fetal ECG ST-segment analysis (ECG-F group). In the CTG group fetal heart rate was interpreted according to guidelines from the National Institute of Child Health and Human Development, whereas in the ECG-F group the tracings were interpreted according the original International Federation of Gynecology and Obstetrics (FIGO) guidelines. The primary outcome measure was neonatal outcome, evaluated as arterial blood pH in neonates after abdominal or vaginal operative delivery indicated because of nonreassuring fetal status. ResultsA total of 237 women were randomized, of whom 200 were included in the final analysis (100 in each group). The rate of cesarean delivery was the same in both groups (26%), and the rate of operative delivery due to nonreassuring fetal status did not differ significantly (38% in the CTG group vs. 39% in the ECG-F group). Regarding neonatal outcomes, there was no significant difference between groups in neonatal pH (7.27 [7.23–7.29] and 7.25 [7.21–7.27]). ConclusionsIn a population comprising only late-term pregnancies, fetal ECG monitoring had no benefits for the mother or fetus. Additional studies are needed of protocols for using ST waveform analysis in selected population groups.

Development of the Pediatric Extracorporeal Membrane Oxygenation Prediction Model for Risk-Adjusting Mortality.

To develop a prognostic model for predicting mortality at time of extracorporeal membrane oxygenation initiation for children which is important for determining center-specific risk-adjusted outcomes. Multivariable logistic regression using a large national cohort of pediatric extracorporeal membrane oxygenation patients. The ICUs of the eight tertiary care children's hospitals of the Collaborative Pediatric Critical Care Research Network. Five-hundred fourteen children (< 19 yr old), enrolled with an initial extracorporeal membrane oxygenation run for any indication between January 2012 and September 2014. None. A total of 514 first extracorporeal membrane oxygenation runs were analyzed with an overall mortality of 45% (n = 232). Weighted logistic regression was used for model selection and internal validation was performed using cross validation. The variables included in the Pediatric Extracorporeal Membrane Oxygenation Prediction model were age (pre-term neonate, full-term neonate, infant, child, and adolescent), indication for extracorporeal membrane oxygenation (extracorporeal cardiopulmonary resuscitation, cardiac, or respiratory), meconium aspiration, congenital diaphragmatic hernia, documented blood stream infection, arterial blood pH, partial thromboplastin time, and international normalized ratio. The highest risk of mortality was associated with the presence of a documented blood stream infection (odds ratio, 5.26; CI, 1.90-14.57) followed by extracorporeal cardiopulmonary resuscitation (odds ratio, 4.36; CI, 2.23-8.51). The C-statistic was 0.75 (95% CI, 0.70-0.80). The Pediatric Extracorporeal Membrane Oxygenation Prediction model represents a model for predicting in-hospital mortality among children receiving extracorporeal membrane oxygenation support for any indication. Consequently, it holds promise as the first comprehensive pediatric extracorporeal membrane oxygenation risk stratification model which is important for benchmarking extracorporeal membrane oxygenation outcomes across many centers.

Effects of intramuscular alfaxalone-midazolam combination in pigs

The aim of this experimental study was to evaluate the sedative and cardiorespiratory effects of alfaxalone and midazolam after intramuscular administration in pigs. Fourteen pigs, weighing 18 to 22 kg, aged between 55 and 70 days, American Society of Anaesthesiologists classification 2, affected by congenital reducible umbilical hernia, were included in the study. Alfaxalone (5 mg/kg) and midazolam (0.5 mg/kg) mixed in the same syringe were administered into the neck muscle. Pain on injection, quality of sedation and time to achieve lateral recumbency were recorded. Heart rate (HR), respiratory frequency (fR), and rectal temperature (RT) were recorded at 0 (baseline: before drug administration), 10, 15, and 20 min after the injection. Oxygen saturation of haemoglobin (SpO2), arterial blood pH, arterial oxygen (PaO2) and carbon dioxide (PaCO2) tensions and bicarbonate concentration (HCO3-) were recorded at 10, 15, and 20 min after injection. Continuous data were analysed using a repeated-measure analysis of variance (ANOVA) and aP-value &lt; 0.05 was considered significant. Ten animals out of fourteen showed no pain on injection, whereas the remaining four exhibited mild pain. The time from the end of injection to lateral recumbency was 266 ± 40 s. The quality of sedation ranged between good to very good. No significant changes in the variables monitored were observed between the time points. In conclusion, the intramuscular administration of alfaxalone and midazolam in pigs at the doses used induced reliable and fast sedation, without pain on injection and moderate respiratory effects.

Analysis of Neonatal Outcome with Supplemental Oxygen to Mother during Elective Cesarean Section under Spinal Anesthesia: A Prospective Randomized Controlled Trial.

Background:Many questions have arisen on benefits of routine use of supplemental oxygen during elective cesarean section (CS) under spinal anesthesia.Aims:The aim of this randomized controlled study was to evaluate neonatal outcome in immediate postpartum period with or without supplemental oxygen to mother, undergoing elective CS under spinal anesthesia.Materials and Methods:One hundred and thirty-four nonlaboring term pregnant women were allocated randomly into two groups to breathe room air (air group) or oxygen (oxygen group). Times from starting oxygen supplementation to delivery interval, skin incision to delivery (I-D) interval, and uterine incision to delivery (U-D) interval were recorded. APGAR scores were assessed at 1 min and 5 min after delivery. Umbilical cord blood gas analysis was done immediately to measure pH, oxygen partial pressure, carbon dioxide partial pressure (PCO2), and bicarbonate.Statistical Analysis:Statistical comparisons were performed using either Student's t-test or Mann–Whitney U-test.Results:For oxygen group versus air group, In Oxygen group, proportion of fetal acidosis was significantly less; umbilical arterial (UA) blood pH (7.22 ± 0.05 vs. 7.19 ± 0.05, P = 0.001) as well as umbilical venous (UV) blood pH (7.26 ± 0.05 vs. 7.22 ± 0.06, P < 0.001) were significantly higher and UA PCO2 (55.4 ± 9.9 vs. 62.9 ± 6.9, P = 0.001) and UV PCO2 (51.4 ± 8.2 vs. 54.3 ± 7.2, P = 0.036) were significantly lower compared to air group. APGAR scores were similar between the groups.Conclusions:Supplemental oxygen has potential benefits as demonstrated by less proportion of FA in mothers receiving supplemental oxygen.

Arterial and end-tidal Carbon Dioxide Tension Changes during Spinal Anaesthesia in Upper Abdominal Laparoscopic Surgeries: A Comparison with General Anaesthesia

&#x0D; Nowadays, laparoscopic surgeries are being performed under subarachnoid block (SAB) safely.&#x0D; Aims: This study was to compare the arterial and end-tidal carbon dioxide (CO2) tension changes during spinal and general anaesthesia (GA) in CO2 pneumoperitoneum for upper abdominal laparoscopic surgeries.&#x0D; Settings and Design: This was a prospective randomized comparative clinical study.&#x0D; Materials and Methods: Eighty patients posted for upper abdominal laparoscopic surgeries were randomly allocated to two groups either to receive standard GA or lumbar SAB.&#x0D; Results: The demographic profiles of both the groups were comparable. The PaCO2 was increased gradually and sustained at its peaks within 20±4.37 minutes in both the groups. The mean±SD revealed to be higher in Group B (41.5500±2.1315) than Group A (40.8460±2.1136), but the difference between the two was not statistically significant (P=0.6142). There was a gradual increase in ETCO2 over the initial 10±2.07 minutes and reached a plateau within 20±5.74 minutes in both the groups and declined faster after deflation of pneumoperitoneum in SAB group. The mean±SD was found to be higher in Group B (33.923±1.642) than Group A (33.408±1.772), but it was also not statistically significant (P=0.4492). The difference of the arterial blood pH between the groups was not statistically significant. Three (7.5%) patients developed transient urinary retention and 2 (5%) patients suffered from post-dural puncture headache in SAB group.&#x0D; Conclusions: Arterial and end-tidal CO2 tension changes during upper abdominal laparoscopic surgery under SAB remain within physiological limit and comparable to the CO2 tensions under GA. However, per-operative complications in SAB are greater, while it is lesser in postoperative period in comparison to GA. SAB may be adopted in ASA physical status I patients with proper preoperative counselling.&#x0D; J Bangladesh Coll Phys Surg 2019; 37(1): 13-18&#x0D; &#x0D;

Inhibition of RHO Kinase by Fasudil Attenuates Ischemic Lung Injury After Cardiac Arrest in Rats.

Lung injury is a common complication after cardiac arrest (CA) and cardiopulmonary resuscitation (CPR), and Rho kinase (ROCK) may be involved in the process of this injury. In this study, we aimed to study the effects of ROCK inhibition by fasudil on lung injury induced by asphyxial CA and CPR in rats. A total of 130 rats were randomized into three groups: Sham, Control, and Fasudil intervention group. Animals in the Fasudil intervention group were intraperitoneally administered with 10 mg/kg of the drug, 1 h before inducing CA. Rats in the Control group received equivalent volume of saline and were subjected to the same experimental procedures with as the Fasudil group. Blood was collected and lungs were harvested at 3, 6, 12, 24, and 48 h after return of spontaneous circulation (ROSC) for blood gas and biochemical analysis. Fasudil significantly increased the partial pressure of oxygen and pH in arterial blood, as well as attenuated lung histological injury and lung edema after ROSC. Additionally, it significantly decreased lung inflammatory response (decreased levels of tumor necrosis factor-α and interleukin-6, and myeloperoxidase activity) and oxidative stress (decreased malonaldehyde level and increased superoxide dismutase activity) after ROSC. Using western blot analysis, we found that fasudil inhibited both isoforms ROCK1 and ROCK2, and intercellular adhesion molecule-1; nevertheless, it increased vascular endothelial cadherin protein expression after ROSC. Our study suggested that the Rho kinase signaling pathway is critical for CA-induced lung injury and fasudil has protective effects on lung injury after CA and CPR.

Neurovascular Coupling Remains Intact During Incremental Ascent to High Altitude (4240 m) in Acclimatized Healthy Volunteers.

Neurovascular coupling (NVC) is the temporal link between neuronal metabolic activity and regional cerebral blood flow (CBF), supporting adequate delivery of nutrients. Exposure to high altitude (HA) imposes several stressors, including hypoxia and hypocapnia, which modulate cerebrovascular tone in an antagonistic fashion. Whether these contrasting stressors and subsequent adaptations affect NVC during incremental ascent to HA is unclear. The aim of this study was to assess whether incremental ascent to HA influences the NVC response. Given that CBF is sensitive to changes in arterial blood gasses, in particular PaCO2, we hypothesized that the vasoconstrictive effect of hypocapnia during ascent would decrease the NVC response. 10 healthy study participants (21.7 ± 1.3 years, 23.57 ± 2.00 kg/m2, mean ± SD) were recruited as part of a research expedition to HA in the Nepal Himalaya. Resting posterior cerebral artery velocity (PCAv), arterial blood gasses (PaO2, SaO2, PaCO2, [HCO3-], base excess and arterial blood pH) and NVC response of the PCA were measured at four pre-determined locations: Calgary/Kathmandu (1045/1400 m, control), Namche (3440 m), Deboche (3820 m) and Pheriche (4240 m). PCAv was measured using transcranial Doppler ultrasound. Arterial blood draws were taken from the radial artery and analyzed using a portable blood gas/electrolyte analyzer. NVC was determined in response to visual stimulation (VS; Strobe light; 6 Hz; 30 s on/off × 3 trials). The NVC response was averaged across three VS trials at each location. PaO2, SaO2, and PaCO2 were each significantly decreased at 3440, 3820, and 4240 m. No significant differences were found for pH at HA (P > 0.05) due to significant reductions in [HCO3-] (P < 0.043). As expected, incremental ascent to HA induced a state of hypoxic hypocapnia, whereas normal arterial pH was maintained due to renal compensation. NVC was quantified as the delta (Δ) PCAv from baseline for mean PCAv, peak PCAv and total area under the curve (ΔPCAv tAUC) during VS. No significant differences were found for Δmean, Δpeak or ΔPCAv tAUC between locations (P > 0.05). NVC remains remarkably intact during incremental ascent to HA in healthy acclimatized individuals. Despite the array of superimposed stressors associated with ascent to HA, CBF and NVC regulation may be preserved coincident with arterial pH maintenance during acclimatization.

Assessing the Efficacy of Ventilation of Anesthetized Neonatal Calves Using a Laryngeal Mask Airway or Mask Resuscitator.

Calves that have undergone a dystocia are often hypoxic and acidemic, which can result in reduced vigor and subsequent mortality. Methods of field resuscitation of apneic newborn calves are often ineffective and therefore underutilized. This proof-of-concept study aimed to determine the efficacy of the laryngeal mask airway (LMA) as well as the current industry standard method of ventilation, the McCulloch Calf Aspirator/ Resuscitator (MMR) for positive pressure ventilation of neonatal calves. Five LMA models of various sizes were first tested in cadaver heads to assess anatomical fit. Three LMA models in two sizes each were then tested in two anesthetized calves to determine the model best suited to ventilate calves. Next, the selected LMA and the MMR were both assessed for efficacy of ventilation. Six anesthetized calves had hypoventilation induced by administering alfaxalone intravenously. Calves were ventilated for 3 min with the LMA, allowed a brief washout period, then given a second administration of alfaxalone prior to ventilation with the MMR. Serial arterial blood gas analyses were performed prior to ventilation (baseline), at 1, 2, and 3 min during ventilation, and 1 min after ventilation had ceased. Success of ventilation was assessed by monitoring partial pressure of oxygen (PaO2), partial pressure of carbon dioxide (PaCO2), bicarbonate (), pH, L-lactate, and hemoglobin saturation (SaO2) in arterial blood. A one-way ANOVA for repeated measures with Bonferroni correction was used to assess the efficacy of ventilation of each device compared to baseline. For the LMA, PaO2, SaO2, and pH were significantly higher than baseline throughout ventilation and PaCO2 was significantly lower than baseline at 1 min of ventilation. For the MMR, PaO2 and SaO2 were significantly higher and PaCO2 and were significantly lower than baseline for 1 to 2 min of ventilation. This proof-of-concept study showed the LMA is an effective means of ventilating neonatal calves, as was the MMR.

T-cell immunoglobulin mucin-3 and galectin-9 levels in peripheral blood mononuclear cells predict fetal acidemia in twin pregnancies

Purposes: The pH in the umbilical artery at delivery provides information on the fetal environment and is related to postnatal outcomes. The ability to predict fetal acidemia at delivery would improve clinical management and neonatal well-being. We hypothesized that an alteration in maternal immunity would accompany placental changes that precede a decrease in pH in the fetal circulation in twin gestations. Methods: Peripheral blood mononuclear cells (PBMCs), obtained from 86 women with twin pregnancies, were lysed and assayed for concentrations of T-cell immunoglobulin mucin domain 3 (Tim-3) and galectin-9 (gal-9) by ELISA. Tim-3–gal-9 interaction is a primary mechanism promoting immune suppression. At delivery, the pH of arterial cord blood was determined. Results: In eight women (9.3%), the pH in the placental arteries from both twins was <7.15, indicating fetal acidosis. In the remaining 78 women the arterial pH was ≥7.15 in both twins. The median Tim-3 level was 361 pg/ml when arterial pH was <7.15 and 199 pg/ml when pH was ≥7.15 (p = .003). Similarly, gal-9 was 31.2 versus 12.4 ng/ml when pH was <7.15 or ≥7.15, respectively (p = .001). A Tim-3 concentration >260 pg/ml predicted arterial pH <7.15 with a sensitivity of 87.5%, specificity of 79.5% and negative predictive value of 98.4%. A gal-9 level >18.4 predicted arterial pH <7.15 with a sensitivity of 100%, specificity of 73.8% and a negative predictive value of 100%. Conclusion: We conclude that elevations in Tim-3 and gal-9 in PBMCs during gestation predict the subsequent occurrence of a pH <7.15 in the fetal arteries at delivery in twin gestations.