Carbon Monoxide Poisoning from Heavy Cigarette Smoking Presenting as Delusion in a Patient with a History of Chronic Schizophrenia (Methamphetamine Induced)

We describe a case of carbon monoxide poisoning in a 54-year-old male from heavy cigarette smoking presenting as delusions. The patient has a history of methamphetamine-induced schizophrenia now in remission for 2 years, and not on any psychotropics and is drug-free.

Arterial Blood Gases in Normal Subjects at 2240 Meters Above Sea Level: Impact of Age, Gender, and Body Mass Index

ABSTRACT Background The values of arterial blood gases (ABG) change with altitude above sea level; empirical verification is essential because ventilatory acclimatization varies with ethnicity and a population's adaptation. Objective The aim of the study was to describe ABG in a healthy population residing at 2,240 meters above sea level, to identify the mean level of alveolar ventilation (PaCO2), and to know whether a progressive increase in PaCO2 occurs with age and the impact of increasing body mass index (BMI). Methods We conducted a cross-sectional study in a referral center for respiratory diseases in Mexico City. Associations among variables with correlation coefficient and regression models of PaO2, SaO2, and P(A-a)O2 as dependent variables as a function of age, BMI, minute ventilation, or breathing frequency were explored. Results Two hundred and seventeen healthy subjects were evaluated with a mean age of 40 ± 15 years, mean of the PaO2 was 71 ± 6 mmHg, SaO2 94% ± 1.6%, PaCO2 30.2 ± 3.4 mmHg, HCO3 20 ± 2 mmol/L, BE-2.9 ± 1.9 mmol/L, and the value of pH was 7.43 ± 0.02. In a linear regression, the main results were PaO2 = 77.5-0.16*age (p < 0.0001) and with aging P(A-a)O2 tended to increase 0.12 mmHg/year. PaCO2 in women increased with age by 0.075 mmHg/year (p = 0.0012, PaCO2 =26.3 + 0.075*age). SaO2 and PaO2 decreased significantly in women with higher BMI 0.14% and 0.52 mmHg per kg/m2, (p = 0.004 and 0.002 respectively). Conclusion Mean PaCO2 was 30.7 mmHg, implying a mean alveolar ventilation of around 30% above that at sea level.

Prognostic analysis of 55 neonates with severe asphyxia / 预防医学

Objective@#To analyze the prognosis of neonates with severe asphyxia, so as to provide insights into improvements of prognosis among neonates with severe asphyxia. @*Methods@#Neonates with severe asphyxia born in Hangzhou Women's Hospital from 2016 to 2021 were recruited, and neonates' birth weight, gender, Apgar score, arterial blood pH value within 30 minutes after birth and maternal delivery data were collected. Outpatient follow-up was performed among neonates one year after birth, and the prognosis was evaluated with the Gesell Developmental Scale. Death or development quotient (DQ) of <75 was defined poor prognosis, and the clinical characteristics were compared between the good prognosis group and the poor prognosis group.@*Results@#A total of 55 neonates with severe asphyxia were enrolled, including 26 boys and 29 girls, with a median birth weight of 2 845.00 g (interquartile range, 1 948.00 g). There were 52 lying-in women (3 women had twins), with a mean age of (30.56±4.08) years, including 35 women with dystocia (67.31%) and 37 primiparas (71.15%). Of 55 neonates with severe asphyxia, there were 40 neonates with good prognosis (72.73%) and 15 neonates with poor prognosis (27.27%), including 13 deaths and 2 cases with DQ of <75. The incidence of abnormal fetal position was higher in the good prognosis group than in the poor prognosis group (36.84% vs. 0%; P<0.05), and the incidence of uterine torsion or uterine rupture was higher in the poor prognosis group than in the good prognosis group (21.43% vs. 0%; P<0.05). The median Apgar score at 5 min after birth and arterial blood pH within 30 min after birth were lower in the poor prognosis group [3.00 (interquartile range, 4.00) points and (6.93±0.23)] than in the good prognosis group [6.00 (interquartile range, 4.00) points and (7.23±0.15)] (P<0.05).@*Conclusion@#Maternal uterine torsion or uterine rupture, low Apgar score at 5 min after birth, and low arterial blood pH within 30 min after birth may aggravate the poor prognosis among neonates with severe asphyxia.

Discussion on the zero-calibration and the zero line in the measurement of central venous pressure and invasive arterial blood pressure / 中华危重病急救医学

Objective:To figure out the timing of zeroing and the location of the zero line in the central venous pressure (CVP) monitoring and invasive arterial blood pressure (IBP) monitoring, and to provide scientific and accurate data for patients management.Methods:The liquid vessel models were used to simulate the pressure measurement process of the continuous pressure monitoring system. Based on the theory of fluid mechanics and the knowledge of blood pressure physiology and cardiovascular anatomy, the composition and influencing factors of the pressure in the fluid-filled catheter system during the zeroing and placing the transducer in the zero line of CVP and IBP, were analyzed.Results:The pressure in the liquid-filled catheter system was composed of atmospheric pressure, the pressure of pumping bag, the gravity of the water column (the vertical distance between the liquid level of Murphy's dropper and pressure transducer, ΔH), and the resistance of tube wall. This pressure value is set as a pressure of 0 mmHg (1 mmHg ≈ 0.133 kPa). In the process of pressure measurement, when the pressure transducer was placed at a horizontal position of 10 cm below the highest liquid level of the vessel, the pressure measured at different catheter tip positions was all 10 cmH 2O (1 cmH 2O ≈ 0.098 kPa); When the pressure transducer was placed at the horizontal position of the highest liquid level of the vessel, the measured pressure is 0 mmHg. Conclusion:Zeroing should repeatedly be performed only when one or more conditions (atmospheric pressure, pressure of pumping bag, gravity of ΔH water column and resistance of tube wall) are changed. In the measurement process, the pressure transducer should be placed at the zero line position at any time to eliminate the influence of hydrostatic pressure and to ensure the objective and accurate value.

Application of blended learning combined with Jigsaw teaching in arterial blood specimen collection of undergraduate intern nurses / 中华医学教育探索杂志

Objective:To explore the application effect of online and offline blended learning combined with Jigsaw teaching in arterial blood specimen collection of undergraduate nursing interns.Methods:A total of 135 undergraduate nursing interns were randomly divided into the experimental group ( n=66) and the control group ( n=69). The experimental group used the blended learning combined with Jigsaw teaching, while the control group adopted the blended learning combined with PBL teaching. The theoretical examination before and after class, the skill assessment after training, the nursing clinical decision-making consciousness scale, and the teaching satisfaction survey were conducted in the two groups. SPSS 28.0 was used for t-test and Chi-square test. Results:After teaching, the total score of courses and the score of theoretical examination and skill assessment of the experimental group were higher than those of the control group, and the differences were statistically significant ( P<0.05). The total score and the multi-dimension scores of the nursing clinical decision-making consciousness scale in the experimental group were higher than those in the control group, and the differences were statistically significant ( P<0.05). The teaching satisfaction of the experimental group was 92.42% (61/66), which was significantly higher than that of the control group [69.57% (48/69)], and the differences were statistically significant ( P<0.05). Conclusion:Blended learning combined with Jigsaw teaching is applied to collect arterial blood specimens for undergraduate nursing interns, which is beneficial to improve the academic performance and clinical decision-making ability of nursing students.

Effect of repeated episodes of ventricular fibrillation and defibrillation on arterial acid-base and electrolytes changes in a swine model / 中华急诊医学杂志

Objective:To investigate changes in arterial acid-base and electrolytes after repeated episodes of ventricular fibrillation (VF) and defibrillation in a swine model.Methods:Sixteen Peking white swine, weighting (32±2.5) kg, were placed with temporary pacemaker electrodes via the left femoral vein into the right ventricle after anesthesia. Then VF was electrically induced by using a programmed electrical stimulation instrument. An arterial cannula was inserted into the left femoral artery to measure mean arterial blood pressure and cardiac output using a PiCCO monitor, with blood samples collected. The pigs were randomly divided into two group: the manual defibrillation group (MD, n=8) and the automated external defibrillation group (AED, n=8). The first defibrillation was attempted with the manufacturer’s dose (150 J) for 15 s after the successful induction of VF in the MD group. If spontaneous circulation was not recovered, 2-min chest compression and subsequent defibrillation (200 J) were attempted. For the AED group, the defibrillation was delivered following voice prompts of the AED. After the return of spontaneous circulation, the pig was allowed to stabilize for 30 min, followed by the induction of the next episode of VF. The above process was repeated five times. Arterial blood gas, cardiac biomarkers, and hemodynamic variables were measured at 30 min after the return of spontaneous circulation. Results:All pigs were successfully induced VF five times and defibrillated successfully. There were no significant changes in heart rate and mean arterial blood pressure between the two groups after repeated episodes of VF and defibrillation. Compared with baseline measurements, cardiac output tended to decrease after repeated episodes of VF and defibrillation but was not statistically significant (all P>0.05). There were no significant differences in arterial pH, HCO 3-, sodium, and lactic acid in the two groups between each measurement time point and baseline values after repeated VF (all P>0.05), but potassium levels in the two groups decreased with time, and the difference was statistically significant compared with the baseline measurement (all P<0.05). There were no significant differences in myoglobin, creatine kinase isoenzyme-MB, and cardiac troponin I for the two groups compared with baseline values after repeated episodes of VF and defibrillation or various episodes of VF between the two groups (all P > 0.05). Conclusions:Repeated episodes of VF and defibrillation have no significant effect on pH balance, but significantly decrease blood potassium. Clinical approaches (MD vs. AED) do not affect defibrillation effect, with no significant differences in hemodynamic variables and myocardial injuries.

Predictive value of Pcv-aCO 2 on left ventricular ejection fraction in myocardial infarction / 中华急诊医学杂志

Objective:To investigate the relationship between central venous-arterial blood carbon dioxide partial pressure difference (Pcv-aCO 2) and left ventricular ejection fraction(LVEF) in acute myocardial infarction. Methods:Clinical data of patients with acute myocardial infarction admitted to the Intensive Care Unit of Fujian Provincial Hospital from November 2019 to October 2021 were retrospectively analyzed. LVEF was measured by bedside echocardiogram. The patients were divided into the normal LVEF group (LVEF ≥ 52%) and decreased LVEF group (LVEF < 52%) according to LVEF. The differences in general information and hemodynamic parameters between the two groups were compared. The normality of the above data was tested by the Jarque-Bera test. Correlation analysis of hemodynamic indices with LVEF was performed. Binary logistic regression was used to analyze the risk factors associated with the decrease in LVEF. The feasibility of diagnosing LVEF decline with Pcv-aCO 2 was assessed using receiver operating characteristic (ROC) curve. Results:Seventy-two patients with acute myocardial infarction were included for analysis, including 25 patients in the normal LVEF group and 47 patients in the decreased LVEF group. Pcv-aCO 2 was significantly higher in the decreased LVEF group than that in the normal LVEF group [(7.13±1.19) mmHg vs. (5.41±1.23) mmHg, P<0.01]. There was a negative correlation between LVEF and Pcv-aCO 2 ( rs= -0.740, P<0.01). The area under the ROC curve for Pcv-aCO 2 was 0.849 (95% CI: 0.758-0.939, P<0.01). The binary logistic regression analysis showed that Pcv-aCO 2 was an independent risk factor for decreased LVEF ( OR=2.251, 95% CI: 1.326-3.820). Conclusions:To a certain extent, the increase of Pcv-aCO 2 can predict the decrease of LVEF in acute myocardial infarction.

The Clinical Effect of Pretreatment with Heat-sensitive Moxibustion on Primary Dysmenorrhea and Its Influence on Uterine Artery Blood Flow： A Randomized， Blinded Controlled Trial / 中医杂志

ObjectiveTo compare the clinical effect of heat-sensitive moxibustion before menstruation and since the first day of menstruation on primary dysmenorrhoea （PD）， thereby optimizing the clinical treatment plan. MethodsSixty patients with PD were randomly divided into pretreatment group （treated before menstruation） and conventional treatment group （treated since the first day of menstruation） of 30 cases each. For all patients， the area surrounded by bilateral Zigong （EX-CA1） and bilateral Guilai （ST 29） in the supine position， and that formed by bilateral Shenshu （BL 23） and Ciliao （BL 32） in the prone position were selected for circling moxibustion （2 min）， sparrow-pecking moxibustion （1 min）， and then moxibustion along the channels to stimulate the moxibustion sensation and obtain two heat-sensitive points with the best sensation for treatment. In the pretreatment group， moxibustion was applied 3-7 days before the onset of menstruation， and in the conventional treatment group， moxibustion was applied on the day of menstruation. Both groups were treated once daily for 7 days per menstrual cycle for 3 consecutive cycles. The clinical outcomes of the two groups were measured before and after treatment in terms of the COX menstrual pain symptom scale （CMSS） scores， visual analogue scale for pain （VAS） scores， and uterine artery hemodynamic indicators including blood pulsation index （PI） and resistance index （RI）， and the clinical effect was compared. ResultsAfter treatment， the CMSS scores， VAS scores， PI and RI in the two groups decreased， and lower scores were found in the pretreatment group （P＜0.05 or P＜0.01）. The total effective rate after treatment was 93.3% （28/30） in the pretreatment group， which was better than 73.3% （22/30） in the conventional treatment group （P＜0.05）. ConclusionThe clinical effect of heat-sensitive moxibustion before the menstruation for PD was better than that implemented since the first day of menstruation， by significantly improving the patients' dysmenorrhoea symptoms and uterine artery blood flow index.

Delta de CO2 como estrategia del manejo integral del paciente con choque séptico en la UCI / CO2 delta as a strategy for the comprehensive management of patients with septic shock in the ICU / Delta CO2 como estratégia para o tratamento integral do paciente com choque séptico na UTI

Resumen: Introducción: el choque séptico es un subconjunto de sepsis en el que las anomalías circulatorias, celulares y metabólicas subyacentes son lo suficientemente profundas para aumentar de manera sustancial la mortalidad. Estos pacientes pueden ser identificados en un contexto clínico de choque séptico con hipotensión persistente. La importancia de vigilar valores de delta de pCO2 (presión parcial de dióxido de carbono) de 6 mmHg sirve como herramienta complementaria para evaluar el flujo sanguíneo adecuado hacia la demanda metabólica global. Objetivo: demostrar que el delta de pCO2 es útil en el manejo integral del paciente con choque séptico en la unidad de cuidados intensivos para dirigir el tratamiento de acuerdo con este biomarcador, que se registró al ingreso y a las 24 horas, se relacionaron al pronóstico y a la mortalidad en choque séptico. Material y métodos: estudio descriptivo, ambispectivo, longitudinal y analítico. El universo se compuso de los pacientes que ingresaron a la Unidad de Cuidados Intensivos del Hospital General «La Villa¼ y del Hospital General «Dr. Rubén Leñero¼. Diseño de la maniobra: se tomaron gasometrías arterial y venosa de los pacientes que ingresaron a la UCI, se calculó el delta de pCO2 para ver si los valores de este biomarcador estaban por arriba o debajo de 6 mmHg, ya que un delta de pCO2 se relaciona con mortalidad; sin embargo, el delta de pCO2 se comparó contra el lactato para correlacionar niveles mayores de lactato de 2 mmol/L con la mortalidad. y finalmente observar cuál de los dos biomarcadores es más útil. Se utilizó estadística descriptica para los resultados. Conclusión: de acuerdo a los resultados encontrados en este estudio, se puede decir que el delta de pCO2 y el lactato predijeron el fallecimiento de 15%, lo cual tiene una significancia positiva débil (p = 0.245).

Abstract: Introduction: septic shock is a subset of sepsis in which underlying circulatory, cellular, and metabolic abnormalities are profound enough to substantially increase mortality. These patients can be identified in a clinical setting of septic shock with persistent hypotension. The importance of monitoring delta pCO2 values of 6 mmHg serves as a complementary tool to assess adequate blood flow towards global metabolic demand. Objective: to demonstrate that the pCO2 delta is useful in the comprehensive management of patients with septic shock in the Intensive Care Unit to direct the treatment according to this biomarker (pCO2 delta) that was recorded at admission and at 24 hours, were related to prognosis and mortality in septic shock. Material and methods: descriptive, ambispective, longitudinal and analytical study. The universe was made up of patients admitted to the ICU of the La Villa and Rubén Leñero General Hospitals. Maneuver design: arterial and venous blood gases were taken from the patients admitted to the ICU, the pCO2 delta was calculated to see if the values of this biomarker were above or below 6 mmHg, since a pCO2 delta is related to with mortality; however, delta pCO2 was compared against Lactate to correlate lactate levels greater than two with mortality and finally see which of the two biomarkers is more useful. Descriptive statistics were used for the results. Conclusion: according to the results found in this study, it can be said that delta pCO2 and lactate predicted the death of 15%, which has a weak positive significance (p = 0.245).

Resumo: Introdução: choque séptico é um subconjunto de sepse em que anormalidades circulatórias, celulares e metabólicas subjacentes são profundas o suficiente para aumentar substancialmente a mortalidade, esses pacientes podem ser identificados em um cenário clínico de choque séptico com hipotensão persistente. A importância do monitoramento de valores Delta de pCO2 de 6 mmHg serve como ferramenta complementar para avaliar o fluxo sanguíneo adequado à demanda metabólica global. Objetivo: demonstrar que o Delta pCO2 é útil no manejo integral de pacientes com choque séptico na Unidade de Terapia Intensiva para direcionar o tratamento de acordo com este biomarcador (Delta pCO2) que foi registrado na admissão e em 24 horas, relacionado ao prognóstico e mortalidade no choque séptico. Material e métodos: estudo descritivo, ambispectivo, longitudinal e analítico. O universo foi constituído pelos pacientes internados na UTI dos Hospitais Gerais La Villa e Rubén Leñero. Desenho da estratégia: foram coletadas gasometrias arteriais e venosas dos pacientes internados na UTI, o Delta pCO2 foi calculado para ver se os valores desse biomarcador estavam acima ou abaixo de 6 mmHg, pois um Delta pCO2 está relacionado com mortalidade; entretanto, Delta pCO2 foi comparado com Lactato para correlacionar níveis de lactato maiores que 2 com mortalidade e finalmente observar qual dos dois biomarcadores é mais útil. Foram usadas estatísticas descritivas para os resultados. Conclusão: de acordo com os resultados encontrados neste estudo, pode-se dizer que Delta pCO2 e Lactato predizem óbito em 15%, o que tem uma fraca significância positiva (p = 0.245).

Primary assessment of patients admitted to the emergency ward using arterial blood gas

Background: Arterial blood gas study (ABG) is a point-of-care testing (POCT) diagnostic tool that can furnish metabolic and respiratory aberrations. This study was conducted systematically, to assess the metabolic and respiratory aberrations quickly and the scope for corrective treatment so that metabolic and respiratory abnormalities get corrected. Materials and Methods: A prospective cross-sectional study was done among 150 cases admitted to the Department of Emergency Medicine during a three-month period where the study on ABG was done. Data was collected in the prescribed format and a stepwise interpretation of the ABG was done. The four primary disorders taken into consideration are metabolic acidosis, metabolic alkalosis, respiratory alkalosis, and respiratory acidosis Results: Out of 150 cases 82 had respiratory alkalosis, 51 had metabolic acidosis, ten had respiratory acidosis, and seven had metabolic alkalosis as a primary disorder. Conclusion: ABG analysis is a POCT diagnostic tool for analyzing various metabolic and respiratory aberrations and can also guide us in the scope for correction of the disorder.

Alteraciones del estado ácido básico en pacientes adultos con insuficiencia renal crónica / Acid-base status alterations in adult patients with chronic renal failure

RESUMEN Introducción: el portador de insuficiencia renal crónica puede presentar diversas alteraciones del estado ácido básico, siendo la acidosis metabólica la más frecuente. Objetivos: describir las características demográficas y clínicas y las alteraciones del estado ácido básico de pacientes adultos que ingresan con insuficiencia renal crónica en dos centros hospitalarios del Paraguay. Metodología: se aplicó un diseño observacional, descriptivo, transversal. Se incluyó a sujetos adultos de ambos sexos, portadores de insuficiencia renal crónica, que acudieron al Hospital Nacional (Itauguá) y Hospital Militar (Asunción) entre abril y noviembre del 2021. Se midieron variables antropométricas, clínicas y laboratoriales al ingreso. Los datos se sometieron a estadística descriptiva con el programa Epi Info 7™. El estudio contó con la aprobación del Comité de Ética de la Universidad Privada del Este, Paraguay. Resultados: se incluyó a 148 sujetos, siendo 78 (52,7 %) varones con edad media 58 ± 16 años y 70 (47,3 %) mujeres con edad media 54 ± 17 años. Las etiologías más frecuentes de la insuficiencia renal crónica fueron la diabetes mellitus e hipertensión arterial (44,5 %). Se detectó 12 sujetos (8,1 %) con gasometría normal. La alteración del estado ácido básico más frecuente fue la acidosis metabólica (87,2 %), predominando en este grupo los casos con brecha aniónica normal. Conclusiones: las alteraciones del estado ácido básico predominantes en pacientes con insuficiencia renal crónica fue la acidosis metabólica con brecha aniónica normal. Se sugiere aplicar los cálculos de los mecanismos compensadores para llegar al diagnóstico certero de estas alteraciones metabólicas.

ABSTRACT Introduction: the carrier of chronic renal failure can present various alterations of the basic acid state, being the metabolic acidosis the most frequent. Objectives: to describe the demographic and clinical characteristics and alterations in the acid-base status of adult patients admitted with chronic renal failure in two hospitals in Paraguay. Methodology: an observational, descriptive, cross-sectional design was applied. Adult subjects of both sexes, carriers of chronic renal failure, who attended the National Hospital (Itauguá) and the Military Hospital (Asunción) between April and November 2021 were included. Anthropometric, clinical and laboratory variables were measured at admission. The data was submitted to descriptive statistics with the Epi Info 7™ program. The study was approved by the Ethics Committee of the Universidad Privada del Este, Paraguay. Results: 148 subjects were included, being 78 (52.7 %) men with a mean age of 58 ± 16 years and 70 (47.3 %) women with a mean age of 54 ± 17 years. The most frequent etiologies of chronic renal failure were diabetes mellitus and arterial hypertension (44.5 %). 12 subjects (8.1 %) with normal blood gases were detected. The most frequent alteration of the acid-base status was metabolic acidosis (87.2 %), with cases with normal anion gap predominating in this group. Conclusions: the predominant acid-base status alterations in patients with chronic renal failure was metabolic acidosis with normal anion gap. It is suggested to apply the calculations of the compensatory mechanisms to arrive at the accurate diagnosis of these metabolic alterations.

Effect of excessive umbilical cord torsion on fetal and neonatal outcomes / 中国新生儿科杂志

Objective:To study the effect of excessive torsion of the umbilical cord on fetal or neonatal outcomes.Methods:The observation group was selected from the puerperae who delivered in Beijing Obstetrics and Gynecology Hospital from July 2016 to June 2020 with excessive torsion of the umbilical cord. In the same period, the puerperae without excessive torsion of the umbilical cord were selected as the control group with a ratio of 1∶1. The general condition, mode of delivery, perinatal outcomes, and the effect of different umbilical coiling index (UCI) [twisted umbilical cord weeks/umbilical cord length (cm)] on fetal and neonatal outcomes were retrospectively analyzed between two groups.Results:Compared with the control group, the observation group (1 780 cases) had smaller neonatal gestational age [(37.9±3.2) weeks vs. (38.4±2.9) weeks], birth weight [(3 007±726) g vs. (3 354±616) g] and length [(48.5±4.3) cm vs. (49.6±4.1) cm], but higher incidence of fetal distress [34.9% (622/1 780) vs. 12.9% (230/1 780)], neonatal asphyxia [1.5% (26/1 780) vs. 0.7% (13/1 780)], and cord blood pH<7.20 [4.2% (75/1 780) vs. 2.8% (49/1 780)], the difference was statistically significant ( P<0.05). The UCI≥0.73 group had lower neonatal gestational age, birth weight and length, but higher incidence of cord blood pH<7.20 and neonatal asphyxia than the UCI<0.73 group, with statistically significant differences ( P<0.05). Conclusions:Excessive torsion of the umbilical cord increases the incidence of fetal hypoxia and neonatal asphyxia and has a significant effect on neonatal gestational age, birth weight and length. The higher the UCI, the greater the impact on fetus and neonate.

Invasive arterial blood pressure monitoring improves the prognosis of patients with sepsis / 中华急诊医学杂志

Objective:To evaluate the effect of invasive arterial blood pressure (IBP) monitoring on the prognosis of patients with sepsis.Methods:Patients with sepsis from the MIMIC-Ⅳ database were collected and divided into IBP and non-invasive blood pressure monitoring (NIBP) groups according to whether IBP monitoring was performed. Baseline variables that were considered clinically relevant or showed a univariate relationship with the outcome were entered into a multivariate logistic regression model as covariates.Propensity score matching(PSM) and inverse probability of treatment weighing(IPTW) were used to adjust confounders to ensure the robustness of findings.Subgroup analysis were conducted to evaluate the effect of differences in IBP onset and duration on outcome.Results:The 28-day mortality is lower in IBP group compared with NIBP group( OR=0.54, 95% CI 0.46-0.62, P<0.001), the conclusion maintain robust after PSM and IPTW.Then we conducted a series of logistic regression regarding to different initial IBP time(<24 h,24 h-48 h,>48 h) and the initial IBP time within 24 h showed the same results compared to primary outcoms( OR=0.42, 95% CI: 0.36-0.49, P<0.001). IBP duration varied (≤1day, ≤2days, ≤3days, ≤4days, >4days) all showed a statistically significant association with decreased 28-day mortality in the IBP group. Conclusions:IBP is associated with decreased 28-day mortality in patients with sepsis, and the optimal time of IBP is within 24 hours.

Aclaramiento de lactato y déficit de base estándar como pronóstico de mortalidad en choque séptico / Lactate clearance and standard base deficit as a prognosis of mortality in septic shock / Depuração de lactato e deficiência de base padrão como prognóstico de mortalidade no choque séptico

Resumen: Introducción: la asociación del nivel de lactato con la mortalidad en pacientes con sospecha de infección y sepsis está bien establecida. La sensibilidad es entre 66 y 83%, con especificidad de 80 y 85%. Sin embargo, el lactato no es sensible ni lo suficientemente específico para detectar o descartar el diagnóstico por sí solo, ya que el lactato sérico es un biomarcador importante de la hipoxia y disfunción tisular, pero no es una medida directa de la perfusión tisular. El lactato y la base estándar medidos al ingreso a la Unidad de Cuidados Intensivos (UCI) son de utilidad pronóstica en los pacientes críticamente enfermos, pues sus niveles séricos predicen mortalidad a través de la puntuación en sí misma. Pero la importancia real va más allá de un valor absoluto, pues es mejor medir su aclaramiento a través de un tiempo determinado. Objetivo: demostrar que el aclaramiento de lactato y déficit de base estándar registrados al ingreso y a las 24 h se relacionan con mejor pronóstico y disminución de mortalidad en choque séptico. Material y métodos: se utilizó estadística descriptiva (medidas de tendencia central y dispersión; así como frecuencias y porcentajes). Asimismo, se ocupó estadística inferencial con la prueba t de Student, χ2, curva ROC, área bajo la curva e índice de Youden, con un intervalo de confianza de 95%. Resultados: la asociación estadística con la mortalidad se presentó en el aclaramiento de déficit de base estándar y en aclaramiento de lactato. Conclusión: se demostró que el aclaramiento de lactato y déficit de base estándar registrados al ingreso y a las 24 h se relacionaron con mejor pronóstico y disminución de mortalidad en pacientes con choque séptico.

Abstract: Introduction: the association of lactate level with mortality in patients with suspected infection and sepsis is well established. Sensitivity is between 66 and 83%, with specificity between 80 and 85%. However, lactate is neither sensitive nor specific enough to detect or rule out the diagnosis on its own as serum lactate is an important biomarker of tissue hypoxia and dysfunction but is not a direct measure of tissue perfusion. Lactate and standard base measured on admission to the Intensive Care Unit (ICU) are useful for prognosis in critically ill patients since their serum levels predict mortality through the score itself. But the real importance goes beyond an absolute value, since it is better to measure its clearance over a given time. Objective: to demonstrate that lactate clearance and standard base deficit recorded at admission and at 24 hours are related to a better prognosis and decreased mortality in septic shock. Material and methods: descriptive statistics were used (measures of central tendency and dispersion, as well as frequencies and percentages). Likewise, inferential statistics were used with the Student's t test, χ2, ROC curve, area under the curve and Youden index, with a confidence interval of 95%. Results: the statistical association with mortality was presented in the clearance of standard base deficit and in lactate clearance. Conclusion: it was shown that lactate clearance and standard base deficit recorded at admission and at 24 hours were related to a better prognosis and decreased mortality in patients with septic shock.

Resumo: Introdução: a associação do nível de lactato com mortalidade em pacientes com suspeita de infecção e sepse está bem estabelecida. A sensibilidade está entre 66 e 83%, com especificidade de 80 e 85%. No entanto, o lactato não é sensível nem específico o suficiente para detectar ou descartar o diagnóstico por si só, uma vez que o lactato sérico é um importante biomarcador de hipóxia e disfunção tecidual, mas não é uma medida direta da perfusão tecidual. O lactato e a base padrão medidos na admissão na UTI são de utilidade prognóstica em pacientes críticos, uma vez que seus níveis séricos predizem a mortalidade pelo próprio escore. Mas a real importância vai além de um valor absoluto, pois é melhor medir sua depuração em um determinado tempo. Objetivo: demonstrar que a depuração de lactato e o déficit de base padrão registrados na admissão e em 24 horas estão relacionados a um melhor prognóstico e diminuição da mortalidade no choque séptico. Material e métodos: foi utilizada estatística descritiva (medidas de tendência central e dispersão, bem como frequências e percentagens). Da mesma forma, foi utilizada estatística inferencial com teste t de Student, χ2, curva ROC, área sob a curva e índice de Youden, com intervalo de confiança de 95%. Resultados: a associação estatística com a mortalidade foi apresentada na depuração do déficit de base padrão e na eliminação do lactato. Conclusão: foi demonstrado que a depuração de lactato e o déficit de base padrão registrados na admissão e em 24 horas foram relacionados a um melhor prognóstico e diminuição da mortalidade em pacientes com choque séptico.

Valores de la gasometría arterial en pacientes embarazadas con preeclampsia severa / Arterial blood gas parameters in pregnant patients with severe preeclampsia

Resumen OBJETIVO: Determinar e interpretar los valores de la gasometría arterial en pacientes embarazadas con preeclampsia severa. MATERIALES Y MÉTODOS: Estudio observacional, transversal, retrospectivo y descriptivo llevado a cabo en pacientes con más o menos 20 semanas de embarazo y diagnóstico establecido de preeclampsia severa atendidas en la unidad de cuidados intensivos entre el 1 de julio y el 31 de diciembre del 2019. Los datos generales, la condición obstétrica, los estudios de laboratorio clínico y los valores de la gasometría arterial se documentaron conforme a lo registrado en los expedientes clínicos. Se utilizó estadística descriptiva y los datos se procesaron en el programa SPSS versión 20. RESULTADOS: Se estudiaron 30 pacientes con media de edad de 31.6 ± 6.85 años, mediana de paridad 1, todas con feto único de 33.89 ± 3.43 semanas y residencia en la Ciudad de México. Los valores de la gasometría arterial fueron: pH 7.41 ± 0.08, presión parcial de dióxido de carbono 25.51 ± 6.12 mmHg, presión parcial de oxígeno 85.24 ± 41.81 mmHg, hematocrito 33.86 ± 7.51%, ión carbonato 16.95 ± 5.13 mmol/L, patrón de bicarbonato estandarizado 19.04 ± 2.50 mmol/L, gases de efecto invernadero 16.94 ± 2.51 mmHg, exceso de base del fluido extracelular -7.72 ± 5.60 mmol/L, BE (B) -7.36 ± 3.07 mmol/L, porcentaje de saturación de oxígeno 93 ± 8.29, hemoglobina total en la gasometría arterial 10.64 ± 2.36 g/dL, gradiente alvéolo-arterial de oxígeno 49.43 ± 10.98 mmHg, presión parcial de oxígeno 140.43 ± 106.93 mmHg, concentraciones de dióxido de carbono 0.79 ± 0.28 mmHg e Índice respiratorio 0.95 ± 2.57. CONCLUSIONES: Los resultados corresponden a un patrón gasométrico de acidosis metabólica compensada.

Abstract OBJECTIVE: To determine and interpret arterial blood gas values in pregnant patients with severe preeclampsia. MATERIALS AND METHODS: study carry out in a series of 30 patients with a pregnancy ≥ 20 weeks and an established diagnosis of SP admitted to the Intensive Care Unit from July 1 to December 31, 2019, in whom arterial blood gases are part of the routine studies upon admission to the ICU. Patients with recurrence of preeclampsia, eclampsia and HELLP syndrome or with metabolic, respiratory, cardiological and renal morbidities affecting arterial blood gas values were excluded. The general data, obstetric condition, clinical laboratory and arterial blood gas values were documented from the clinical records. Statistical analysis: descriptive statistics were used with the statistical package SPSS version 20. RESULTS: Thirty patients were studied, with a mean age of mean age 31.6 ± 6.85 years, median parity 1, all with a single product of 33.89±3.43 weeks and residence in Mexico City 31.37 ± 7 years. Arterial blood gas values were: pH 7.41 ± 0.08, PCO2 25.51 ± 6.12 mmHg, PO2 85.24 ± 41.81 mmHg, Hct 33.86 ± 7.51%, HCO3- 16.95 ± 5.13 mmol/L, HCO3- std 19.04 ± 2.50 mmol/L, TCO2 16.94 ± 2.51 mmHg, BE ecf -7.72 ± 5.60 mmol/L, BE (B) -7.36 ± 3.07 mmol/L, SO2c% 93 ± 8.29%, THbc 10.64 ± 2.36 g/dL, Aa DO2 49.43 ± 10.98 mmHg, pAO2 140.43 ± 106.93 mmHg, PaO2/PAO2 0.79 ± 0.28 mmHg and Respiratory Index 0.95 ± 2.57. CONCLUSIONS: The results correspond to a gasometric pattern of compensated metabolic acidosis.

Gasometría arterial en embarazo a muy alta altitud / Arterial blood gas analysis during pregnancy at a very high altitude

La gasometría arterial es fundamental en el diagnóstico y manejo del medio interno. El objetivo es caracterizar los valores de gasometría arterial en gestantes sanas con embarazo normoevolutivo residentes a 4 150 metros sobre el nivel del mar. Serie de casos llevada a cabo durante la gestión 2019, la cual incluye pacientes sin clínica ni antecedentes de enfermedades cardiopulmonares o hematológicas, así como ausencia de tabaquismo y residencia de al menos los últimos 6 meses. Se incluye 30 pacientes, media de edad 25.23 años (desvío estándar 3.69), con edad gestacional media de 26 semanas (desvío estándar 5.5). El valor de pH tiende a ser más alto, así como los valores de PaO2, PaCO2, HCO3 y SatpO2% son más bajos, incluso en comparación con adultos sanos residentes de la misma altitud. Existe cierta tendencia positiva hacia el incremento progresivo del pH mientras la edad gestacional avanza. La gasometría arterial en la altura, debe ser interpretada con suma precaución en relación a las condiciones barométricas, proporcionándose así, valiosa información con aplicación a la obstetricia crítica a muy alta altitud.

Arterial blood gases analysis is essential in the diagnosis and management of pathologies. The objective is to characterize arterial blood gases values in healthy pregnant residents at 4150 meters above sea level. Series case performed during 2019, including patients without a clinical features or antecedents of cardiopulmonary or hematological diseases as well as absence of smoking and residence for at least the last 6 months. Thirty patients are included, mean age 25.23 years (standard deviation 3.69), with average gestational age of 26 weeks (standard deviation 5.5). The pH tends to be higher, as well as the values of PaO2, PaCO2, HCO3 and SatpO2% are lower, even compared to healthy adults living at the same altitude. There is some positive trend towards progressive pH is higher such as gestational age progresses. Arterial gas blood analysis at altitude, should be interpreted with extreme caution in relation to barometric conditions, thus providing, valuable information to critical care obstetrics at very high altitude

Lung function and stress echocardiography in pulmonary arterial hypertension: a cross-sectional study

ABSTRACT BACKGROUND: The mechanism of exercise limitation in idiopathic pulmonary arterial hypertension (IPAH) is not fully understood. The role of hemodynamic alterations is well recognized, but mechanical, ventilatory and gasometric factors may also contribute to reduction of exercise capacity in these individuals. OBJECTIVE: To investigate whether there is an association between ventilatory pattern and stress Doppler echocardiography (SDE) variables in IPAH patients. DESIGN AND SETTING: Single-center prospective study conducted in a Brazilian university hospital. METHODS: We included 14 stable IPAH patients and 14 age and sex-matched controls. Volumetric capnography (VCap), spirometry, six-minute walk test and SDE were performed on both the patients and the control subjects. Arterial blood gases were collected only from the patients. The IPAH patients and control subjects were compared with regard to the abovementioned variables. RESULTS: The mean age of the patients was 38.4 years, and 78.6% were women. The patients showed hypocapnia, and in spirometry 42.9% presented forced vital capacity (FVC) below the lower limit of normality. In VCap, IPAH patients had higher respiratory rates (RR) and lower elimination of CO2 in each breath. There was a significant correlation between reduced FVC and the magnitude of increases in tricuspid regurgitation velocity (TRV). In IPAH patients, VCap showed similar tidal volumes and a higher RR, which at least partially explained the hypocapnia. CONCLUSIONS: The patients with IPAH showed hypocapnia, probably related to their higher respiratory rate with preserved tidal volumes; FVC was reduced and this reduction was positively correlated with cardiac output.

The predictive value of stair climbing test combined with arterial blood gas analysis on postoperative complications in lung cancer patients with limited pulmonary function / 中华胸心血管外科杂志

Objective:To evaluate the predictive value of stair climbing test combined with arterial blood gas analysis on postoperative complications in lung cancer patients with limited pulmonary function.Methods:A total of 1 231 hospitalized lung cancer patients with limited pulmonary function dating from August 2012 to August 2020 were retrospectively reviewed. Included in the cohort were 766 of patients who underwent stair climbing test(SCT) preoperatively and completed data collection. Patients were grouped according to their general condition, past medical history, surgical approach, pulmonary function test(PFT) and SCT results. Comparison of the postoperative cardiopulmonary complication rates were made between different groups, and independent risk factors were identified.Results:A total of 182 cardiopulmonary-related complications occurred in 144 cases, accounting for 18.8% of the entire cohort. Perioperative mortality rate was 0.9%(7/766). The rate of postoperative cardiopulmonary complications was significantly different between the groups stratified by gender, age, smoking index, PFT index(FEV1%, DLCO%), SCT results(height achieved, speed, changes in heart rate and oxygen saturation of the arteries before and after the test), ASA score, surgical approach(VATS/Open), resection range(Lobectomy/Sublobectomy), anesthetic duration, blood loss volume, etc. Logistic regression analysis showed that only height achieved( P<0.001), changes in heart rate( P<0.001), changes in oxygen saturation of the arteries( P=0.001), resection range( P=0.006) and anesthetic duration( P=0.025) were independent risk factors for cardiopulmonary-related complications in lung cancer patients with limited pulmonary function. Conclusion:The stair climbing test combined with arterial blood gas analysis could be used as a preoperative screening method for lung cancer patients with limited lung function and may have a predictive value for postoperative cardiopulmonary-related complications.

Changes of arterial blood gas indexes of free-field primary blast lung injury of pigs and its application value / 中华危重病急救医学

Objective:To observe the changes of arterial blood gas indexes in pigs with the free-field primary blast lung injury (PBLI) model, and to explore the value of arterial blood gas indexes in predicting moderate to severe PBLI.Methods:Nine adult healthy Landrace pigs were selected to construct the pig free-field PBLI model. Arterial blood samples were taken 15 minutes before the explosion (before injury) and 10, 30, 60, 120, and 180 minutes after the explosion (after injury). Arterial blood gas indexes and pulse oxygen saturation (SpO 2) were measured, compare the changes of blood gas analysis indexes and SpO 2 levels at different time points, and observe the changes of gross injury scores and pathological injury scores of lung tissue. Analyze the correlation between the blood gas indicators. Results:As time prolonged, at each time point, pH, arterial partial pressure of oxygen (PaO 2), and SpO 2 were lower than those before the injury, and blood lactic acid (Lac) and arterial partial pressure of carbon dioxide (PaCO 2) were higher than those before the injury. Compared with that before the injury, the pH value in the blood decreased significantly 10 minutes after the injury (7.39±0.06 vs. 7.46±0.02, P < 0.05), and the Lac increased significantly (mmol/L: 3.61±2.89 vs. 1.10±0.28, P < 0.05), and lasts until 180 minutes after injury (pH value: 7.37±0.07 vs. 7.46±0.02, Lac (mmol/L): 2.40±0.79 vs. 1.10±0.28, both P < 0.05); while PaO 2 and SpO 2 decreased significantly at 180 minutes after injury [PaO 2 (mmHg, 1 mmHg = 0.133 kPa): 59.40±10.94 vs. 74.81±9.39, P < 0.05; SpO 2: 0.75±0.11 vs. 0.89±0.08, P < 0.05], PaCO 2 increased significantly (mmHg: 56.17±5.38 vs. 48.42±4.93, P < 0.05). Correlation analysis showed that the gross injury score of lung blast injury animals was positively correlated with the pathological injury score ( r = 0.866, P = 0.005); PaO 2 and SpO 2 were positively correlated ( r = 0.703, P = 0.000); pH value and Lac were negative Correlation ( r = -0.400, P = 0.006); pH value is negatively correlated with PaCO 2 ( r = -0.844, P = 0.000). Conclusion:This study successfully established a large mammalian free-field PBLI model, arterial blood gas analysis is helpful for the early diagnosis of PBLI, whether SpO 2 can be used to evaluate the severity of lung injury remains to be further verified.