The value of oxygen index and base excess in predicting the outcome of neonatal acute respiratory distress syndrome

Abstract Objective This study aimed to identify the predictors and threshold of failure in neonatal acute respiratory distress syndrome. Methods Newborns with severe acute respiratory distress syndrome aged 0-28 days and gestational age ≥36 weeks were included in the study if their cases were managed with non-extra corporal membrane oxygenation treatments. Patients were divided into two groups according to whether they died before discharge. Predictors of non-extra corporal membrane oxygenation treatment failure were sought, and the threshold of predictors was calculated. Results A total of 103 patients were included in the study. A total of 77 (74.8%) survived hospitalization and were discharged, whereas 26 (25.2%) died. Receiver operating characteristic analysis of oxygen index, pH, base excess, and combinations of these indicators demonstrated the advantage of the combination of oxygen index and base excess over the others variables regarding their predictive ability. The area under the curve for the combination of oxygen index and base excess was 0.865. When the cut-off values of oxygen index and base excess were 30.0 and −7.4, respectively, the sensitivity and specificity for predicting death were 77.0% and 84.0%, respectively. The model with base excess added a net reclassification improvement of 0.090 to the model without base excess. Conclusion The combination of oxygen index and base excess can be used as a predictor of outcomes in neonates receiving non-extra corporal membrane oxygenation treatment for acute respiratory distress syndrome. In neonates with acute respiratory distress syndrome, if oxygen index >30 and base excess <−7.4, non-extra corporal membrane oxygenation therapy is likely to lead to death.

Base excess as a prognostic factor determining the perinatal outcome

Background: Umbilical cord blood gas assessment seems to be the most objective determination of fetal metabolic condition at the time of birth and can be used to assess the perinatal outcome of the baby. In the early stage of an impaired placental circulation, hypoxemia and hypercapnia result in a decrease in pH with BD maintained normal (respiratory acidemia), whereas if the hypoxic process develops into a sustained anaerobic metabolism the BD rises secondary to lactic acidosis and consumption of buffer.Methods: Observational study done in KIMS hospital Bangalore, Karnataka, India, in a study period of 18 months on a sample size of 100. Within 30 sec of delivery a segment of umbilical cord was clamped at both ends. Cord blood was collected in heparinised syringe. It was then transported with cold ice packs and blood pH, pCO2, pO2 were measured.Results: In present study, there was a significant difference between the 2 groups in terms of BE, BE being highest in the group without complication. There was a moderate negative correlation between duration of NICU stay (days) and BE (mmol/L), and this correlation was statistically significant. There was a significant difference between the 2 groups in terms of BE with the median BE (mmol/L) being highest in the group not requiring resuscitation. At a cutoff of BE (mmol/L) <-17.5, it predicts complications with a sensitivity of 71.4%, and a specificity of 88.2%.Conclusions: Hence cord blood base excess can be used as a prognostic factor in determining the perinatal outcome.

Effect of calcium sources in the diets of adult cats on urinary parameters and acid-base balance / Efeitos das fontes de cálcio na dieta de gatos adultos sobre parâmetros urinários e equilíbrio ácido-básico

Calcium is a macroelement that is part of the mineral composition of the diet of companion animals, and is considered a cation of strong alkalizing power, increasing urinary pH. Calcium salts have different solubilities and depending on the anion to which calcium is associated with, it can be more or less absorbed, modifying the pH of the urine. The aim of this study was to evaluate the efficiency of calcium sources on alkalinization of urinary pH, as well as excretion of urinary electrolytes and acid-base balance of adult cats. An extruded diet for cats was selected, and had 160mEq/kg of calcium from the sources of either calcium carbonate (CaCO3) or calcium gluconate (C12H22CaO14) added. In the control treatment there was no addition of calcium sources, resulting in three treatments. Nine adult cats were used, mixed breed, in two experimental periods, with six replicates per treatment. Animal average age was 4±1.3 years old and average weight was 3.96±0.71kg. The cats remained in metabolic cages for an adaptation period of seven days, followed by six days of urine total collection, with volume, density, pH and calcium concentration (g/d) measurements. The acid-base balance was studied by blood gas analysis of venous blood. The two sources of calcium alkalinized the urine (P<0.001). However, calcium gluconate had less alkalinization power compared to the calcium carbonate (P<0.05). Urinary calcium was not affected by treatments, and represented less than 0.5% of calcium intake. The experiment showed that calcium, although an alkaline cation and considered strong influencer of the EB of the diet, cannot be evaluated individually, because depending on its associated anion it may have greater or lesser influence on cats urine pH.(AU)

O cálcio (Ca) é um macroelemento que faz parte da composição mineral da dieta de animais de companhia. Este macroelemento é considerado um cátion de forte capacidade alcalinizante e, de acordo com a fonte e quantidade inclusa, pode aumentar o pH urinário. Os sais de cálcio têm diferentes solubilidades e dependendo do ânion ao qual o cálcio está associado, pode ser mais ou menos absorvido e assim, alterar o pH da urina. O objetivo deste estudo foi avaliar os efeitos de duas fontes de cálcio na alcalinização do pH urinário, bem como a excreção de eletrólitos urinários e o equilíbrio ácido-básico de felinos. Foi selecionada uma dieta extrusada para gatos e adicionados 160mEq/kg de cálcio das fontes carbonato de cálcio (CaCO3) ou gluconato de cálcio (C12H22CaO14). No tratamento controle, não houve adição de fontes de cálcio. Foram utilizados nove gatos adultos, de raças mistas, em dois períodos experimentais, com seis repetições por tratamento. Os animais apresentavam idade média de 4,0±1,3 anos e peso corporal médio de 3,96±0,71kg. Estes permaneceram em gaiolas metabólicas em período de adaptação durante sete dias, seguido de coleta total de urina durante seis dias. Nestas amostras foram aferidos o volume, densidade, pH e concentração de cálcio (g/d). O equilíbrio ácido-básico foi avaliado por hemogasometria em amostras de sangue venoso. As duas fontes de cálcio alcalinizaram a urina (P<0,001). No entanto, o gluconato de cálcio apresentou menor potencial de alcalinização em comparação ao carbonato de cálcio (P<0,05). O cálcio urinário não foi afetado pelos tratamentos e representou menos de 0,5% da ingestão de Ca. O experimento demonstrou que o cálcio, apesar de ser um cátion alcalinizante e influenciador do EB da dieta, não pode ser avaliado individualmente, porque dependendo do ânion associado, pode apresentar maior ou menor influência no pH da urina de gatos.(AU)

Lactate and base excess as predictors of mortality in patients with Tetralogy of Fallot / 中华胸心血管外科杂志

Objective To explore the distribution of lactate and base excess in children with Tetralogy of Fallot in perio-perative period, its dynamic variation and its relationship with prognosis.Methods Perioperative arterial lactate level was dy-namically monitored in 1 552 children with tetralogy of Fallot.According to the prognosis, 1 505 subjects were assigned to sur-vive group, and 47 subjects to nonsurvive group.The lactate and base excess levels of all subjects were collected after induction (T1), after protamine administration(T2), and 24 h(T3) after surgery in the intensive care unit(ICU).Results The pa-tients who could not survive showed significant elevated lactate levels as compared to patients who survived after surgery [(7.91 ±5.76)mmol/L vs.(1.20 ±0.51)mmol/L, P＜0.05].However, in nonsurvivors, the BE value decreased signifi-cantly in the ICU period in comparison to survivors[(－1.91 ±5.09)mmol/L vs.(2.52 ±2.85)mmol/L, P＜0.05].Logis-tic regression analysis was performed, indicating the elevated lactate and depressed base excess levels measured 24 h after sur-gery were independent risk factors.Conclusion The dynamic monitoring of lactate and base excess levels in the perioperative period in patients with tetralogy of Fallot were sensitive indicators to assess severity , to guide treatments, and for the prognosis. In the perioperative period, when the lactate increased and(or) base excess levels decreased, the mortality rate increased as well.lactate and base excess levels measured 24 h after surgery in the ICU were independent risk factors that significantly in-creased the mortality rate.

Value of base excess in predicting the prognosis of patients with paraquat poisoning / 中华劳动卫生职业病杂志

Objective@#To explore prognostic factors of acute paraquat poisoning (APP) , analyze the correlation between base excess (BE) and plasma concentration of paraquat (C-PQ) and discuss BE level in evalua-tion of prognosis of acute paraquat poisoning patients.@*Methods@#We retrospectively selected 84 APP patients who admitted to Emergency Intensive Care Unit (EICU) of our hospital from 2009.9.1 to 2015.8.31.Clinical data from 84 APP patients were analyzed. BE、C-PQ、time of gastric lavagesince ingestion、time of hemoperfusion since ingestion、severity index of paraquat poisoning (SIPP) 、white blood cell (WBC) 、percentage of neutrophils (N%) 、hemoglobin (HB) 、creatinine (Cr) 、alanine aminotransferase (ALT) 、aspartate aminotransferase (AST) 、partial pressure of oxygen (PaO2) 、partial pressure of carbon dioxide (PaCO2) and other laboratory parameters were measured. A total of 41 patients in non-survivors died during the 30 days after admission and 43 patients in survivors survived during the 30 days. The factors of prognosis in paraquat poisoining and the role of BE in evalu-ating prognosis was analyzed, as well as the correlation between BE and C-PQ.@*Results@#1.Logistic regression analyses showed BE、C-PQ、ALT、AST、Cr was of prognostic significance[odds ratio (OR) of BE: 0.511, 95%CI 0.267, 0.978; C-PQ:-=0.999, 95%CI 0.999, 1.000; both P<0.05] ; 2.The area under the receiver operating characteristic curve (ROC curve) of BE、C-PQ and prognosis were 0.775、0.927 respectively, BE≤-1.7 mmol/L was the best cut-off value, the sensitivity、specificity for predicting were 82.9%、62.8%, the evaluation value was lower to C-PQ>3 273.935 ng/ml (AUC 0.927, 78.0%、95.3%) ; 3.BE negative correlated with C-PQ[-1.100 (-4.100, -0.200) , -5.900(-8.650, -2.500) , both P<0.05]. (r=-0.4, P<0.01).@*Conclusion@#These results suggest that BE may be useful for the prediction of prognosis in PQ poisoning and BE negative correlated with C-PQ.

Can venous base excess replace arterial base excess as a marker of early shock and a predictor of survival in trauma?

<p><b>INTRODUCTION</b>Arterial base excess is an established marker of shock and predictor of survival in trauma patients. However, venous blood is more quickly and easily obtained. This study aimed to determine if venous base excess could replace arterial base excess as a marker in trauma patients at presentation and if venous base excess is predictive of survival at 24 hours and one week.</p><p><b>METHODS</b>This was a prospective study of 394 trauma patients presenting to the emergency department of a tertiary hospital over a 17-month period. Data on base excess at presentation, vital signs, shock index (SI), injury severity score (ISS), and mortality at 24 hours and one week was collected and analysed.</p><p><b>RESULTS</b>Arterial and venous blood gas tests were performed on 260 and 134 patients, respectively. Patients were stratified into groups based on their SI and ISS for analysis. There was no statistical difference between mean venous blood gas and arterial blood gas levels at presentation when SI > 0.7, regardless of ISS (p > 0.05). The mortality rate was 4.57%. Both venous and arterial base excess was lower in nonsurvivors compared to survivors (p < 0.05). However, at 24 hours and one week, the difference in base excess values at presentation between survivors and nonsurvivors was greater when using venous base excess compared to arterial base excess (11.53 vs. 4.28 and 11.41 vs. 2.66, respectively).</p><p><b>CONCLUSION</b>In conclusion, venous base excess can replace arterial base excess in trauma patients as a means of identifying and prognosticating early shock.</p>

Routine measurements of cord arterial blood lactate levels in infants delivering at term and prediction of neonatal outcome

Objective: Our purpose was to evaluate the relationship between umbilical cord arterial blood lactate levels with acid base balance to the mode of delivery and short-term neonatal outcome in a large multiracial population delivering at term in University of Malaya Medical Centre. Materials and methods: Two thousand two hundred and twelve patients of more than 37 weeks of gestation with singleton, liveborn infants with no major anomalies delivering between January 2013 to December 2013 were analysed. Lactate was measured by using portable Lactate analyzer that requires 5 µml of blood and provides the result within 1 minute. The deliveries took place at the Department of Obstetrics and Gynaecology, University Malaya Medical Centre, Malaysia where umbilical cord blood sampling and blood gas analysis is a part of the routine assessment of all newborn. Results: Gestational age ranged from 37 to 43 weeks (mean 39.05 weeks). The highest mean arterial cord lactate values were noted among babies delivered instrumentally (4.87 mmol/L). Infants who had a normal vaginal delivery had the second highest levels (3.36 mmol/L), followed by infants delivered by emergency caesarean section (3.30mmol/L). The lowest lactate values were noted in deliveries by elective caesarean section (3.0mmol/L). Cord arterial lactate levels were significantly higher among infants born with low Apgar scores (7.02 mmol/L vs 4.6mmol/L, P < 0.001). High arterial cord lactate was a significant predictor of admission to Neonatal intensive care unit (NICU) was 6.0mmol/L. Receiver operator curve (ROC) analysis suggests that lactate and pH are virtually equivalent in their correlation with adverse neonatal outcome. Conclusion: Cord lactate levels are significantly related to the mode of delivery and is equivalent to cord arterial pH in predicting adverse neonatal outcomes, with similar efficacies; however, its simplicity, less sampling failure and low cost makes lactate analysis an interesting alternative in obstetric care.

Clinical study of prognostic value of interleukin-6 in diabetic ketoacidosis / 中华急诊医学杂志

Objective To investigate the value of interleukin-6 (IL-6) level as a prognostic indicator in diabetic ketoacidosis (DKA) patients.Methods Data of 88 cases of DKA in Sir Run Run Shaw Hospital collected from June 1,2010 to December 31,2012 were analyzed prospectively.They were divided into two groups according to the survival of patients followed up for 28 days:non-survival group (n =12) and survival group (n =76).Serum levels of IL-6,lactate,base excess and APACHE Ⅱ score in 24 hours after admission were compared between two groups by independent t test.The receiver operating characteristic (ROC) curve was plotted to analyze the performance of IL-6 as a prognostic indicator in the early stage of DKA.Correlations between IL-6 value and lactate,base excess,APACHE Ⅱ score were analyzed.Results The IL-6 values were elevated obviously in non-survival group.The ROC of IL-6 had an area under curve (AUC) of 0.783,and the cut-off value of IL-6 for the death followed up for 28 days was 448.9 ng/L.In all patients,IL-6 values and APACHE Ⅱ score showed a positive correlation between them (r =0.919,P =0.005),and also positive correlations existed between IL-6 and lactate as well as base excess (r=0.922,P=0.003; r=0.887,P=0.015)in24 hours.Conclusions IL-6 value is a reliable prognostic indicator in the early stage of DKA.

The value of early base excess monitoring on predicting prognosis in traumatic brain injury patients / 中国医师进修杂志

Objective To dynamically monitor the base excess(BE) in traumatic brain injury(TBI) patients within 3 d after admission,and to assess the impact of the early BE on prognosis.Methods Blood BE was monitored for 3 d in 56 TBI patients.Patients were classified into mild group(15 patients),moderate group (22 patients) and severe group (19 patients) according to the scores of Glasgow coma scale(GCS).Patients were classified into survival group(42 patients) and dead group(14 patients) according to prognosis.Patients were classified into high BE group (35 patients,BE≥-8 mmol/L) and low BE group (21 patients,BE ＜-8 mmol/L).The relations among BE,degree of injury and prognosis were analyzed.Results The level of BE in mild group,moderate group and severe group was increased after treatment for 1,2,3 d than that before treatment.The level of BE was consistent with the degree of injury [mild group:(-3.02 ± 0.21)mmol/L; moderate group:(-8.49 ± 1.44) mmol/L;severe group:(-9.64 ± 1.19) mmol/L].The level of BE in mild group and severe group had significant difference than that in moderate group (P＜ 0.01).The level of BE in dead group before treatment and after treatment for 1,2,3 d was significantly lower than that in survival group [(-11.97 ±2.13) mmol/L vs.(-6.29 ± 1.16) mmol/L,(-9.84 ± 1.33) mmol/L vs.(-4.89 ± 1.78)mmol/L,(-8.78 ± 2.01) mmol/L vs.(-3.61 ± 1.43) mmol/L,(-7.84 ± 1.42) mmol/L vs.(-3.10 ±0.98)mmol/L] (P ＜0.01).The scores of APACHE Ⅱ before treatment and fatality rate in low BE group were significantly higher than those in high BE group [(24.84 ± 3.68) scores vs.(16.27 ± 2.21) scores,52.4％ (11/21) vs.8.6％(3/35)] (P ＜ 0.01).The scores of GCS before treatment in low BE group was significantly higher than that in high BE group [(7.56 ± 3.09) scores vs.(10.51 ± 2.43) scores](P ＜ 0.01).Conclusion The level of early BE is a good factor on evaluating the condition and prognosis in TBI patients.

The measurement of urine pH to predict the amount of buffer used in the treatment of acute rumen lactic acidosis in cattle

The purpose of the present study was to establish a practical, fast, precise and low-cost procedure to estimate the degree of metabolic acidosis in cattle with acute rumen lactic acidosis for further treatment. The rumen acidosis was induced experimentally in 40 crossbreed rumen-cannulated 1.5-year-old steers. The induction caused the development of the most characteristic clinical signs of acute rumen lactic acidosis, severe rumen acidosis and a moderate metabolic acidosis, which was evidenced by low blood pH, and blood bicarbonate concentration and base excess (BE). A highly positive correlation (r=0.80) between urinary pH and BE concentration, and between urinary pH and blood pH (r=0.75) was observed. The BE concentration estimated by urinary pH was similar to that determined by venous blood gas analysis (P>0.99). Furthermore, the results presented by the predictive formula were very significant. In conclusion, urinary pH is a good tool to predict the quantity of buffers needed to treat metabolic acidosis in cattle with acute rumen lactic acidosis.

O presente estudo teve como objetivo desenvolver um procedimento de baixo custo, preciso, rápido e prático para estimar o grau de acidose metabólica, para tratar bovinos com quadros de acidose láctica ruminal. A acidose ruminal foi induzida experimentalmente em 40 novilhos mestiços de 1,5 anos de idade, implantados com cânula ruminal. Essa indução causou o surgimento de sinais clínicos muito típicos da enfermidade aguda, com o aparecimento de pronunciada acidose ruminal e acidose metabólica de grau moderado, caracterizado por baixo pH sangüíneo e diminutos teores de bicarbonato e excesso de base (BE) no sangue. Verificou-se uma alta correlação positiva (r = 0,80) entre o pH urinário e o BE e entre o pH urinário e o pH sangüíneo (r = 0,75). A concentração de BE estimado pelo pH urinário foi similar à obtida pela análise do hemogasômetro (P = 0,99). Além disso, os resultados apresentados pela fórmula de predição foram muito significativos. Dessa forma, conclui-se que a mensuração do pH urinário é uma boa alternativa para estimar a quantidade necessária de tampão para tratar o quadro de acidose metabólica em bovinos com acidose láctica ruminal aguda.

Clinical utility of standard base excess in the diagnosis and interpretation of metabolic acidosis in critically ill patients

The aims of this study were to determine whether standard base excess (SBE) is a useful diagnostic tool for metabolic acidosis, whether metabolic acidosis is clinically relevant in daily evaluation of critically ill patients, and to identify the most robust acid-base determinants of SBE. Thirty-one critically ill patients were enrolled. Arterial blood samples were drawn at admission and 24 h later. SBE, as calculated by Van Slyke's (SBE VS) or Wooten's (SBE W) equations, accurately diagnosed metabolic acidosis (AUC = 0.867, 95 percentCI = 0.690-1.043 and AUC = 0.817, 95 percentCI = 0.634-0.999, respectively). SBE VS was weakly correlated with total SOFA (r = -0.454, P < 0.001) and was similar to SBE W (r = -0.482, P < 0.001). All acid-base variables were categorized as SBE VS <-2 mEq/L or SBE VS <-5 mEq/L. SBE VS <-2 mEq/L was better able to identify strong ion gap acidosis than SBE VS <-5 mEq/L; there were no significant differences regarding other variables. To demonstrate unmeasured anions, anion gap (AG) corrected for albumin (AG A) was superior to AG corrected for albumin and phosphate (AG A+P) when strong ion gap was used as the standard method. Mathematical modeling showed that albumin level, apparent strong ion difference, AG A, and lactate concentration explained SBE VS variations with an R² = 0.954. SBE VS with a cut-off value of <-2 mEq/L was the best tool to diagnose clinically relevant metabolic acidosis. To analyze the components of SBE VS shifts at the bedside, AG A, apparent strong ion difference, albumin level, and lactate concentration are easily measurable variables that best represent the partitioning of acid-base derangements.

Study of Acid-Base in Arterial and Central Venous Blood during / 대한마취과학회지

BACKGROUND: Although pulmonary artery catheters are useful to monitor hydration, these devices may be associated with severe morbidity and are not routinely used in kidney transplantation. A central venous pressure (CVP) catheter is preferred rather than a pulmonary artery catheter. Noninvasive continuous blood pressure monitors may substitute for intraarterial catheters, thereby preserving the radial artery in kidney transplantation patients should it be needed later to create an arteriovenous fistula. If there is a relationship between central venous and radial arterial blood for acid-base (pH, BE, HCO3(-)), we can use the blood sample from a CVP catheter instead of arterial blood from aradial artery catheter for testing acid-base and it can help patients. METHODS: A central venous catheter and radial artery catheter was inserted in 67 patients while undergoing kidney transplantation. To assess arteriovenous differences in acid-base status at operation start, before reperfusion of the transplanted kidney, after reperfusion, we measured the pH, BE and HCO3(-) simultaneously from the arterial and central venous circulation. RESULTS: Aacid-base using arterial and central venous samples at operation start, before reperfusion and after reperfusionb was evaluated. We found the relationship as follows: pH between arterial (pHa) and central venous blood (pHcv) in each: linear regression equation; pHcv = 0.668 + (0.906 X pHa), pHcv = 0.225 + (0.965 X pHa), pHcv = 0.646 + (0.908 X pHa), determination coefficient; 0.908, 0.926, 0.888, P values < 0.001 in each period. Base excess (BE) between BEa and BEcv in each period: linear regression equation; BEcv = 0.483 + (0.952 X BEa), BEcv = 0.032 + (0.939 X BEa), BEcv = 0.008 + (0.954 X BEa), determination coefficient; 0.844, 0.954, 0.962 P values < 0.001 in each period. HCO3(-) concentration between HCO3(-)a and HCO3(-)cv in each period: linear regression equation; HCO3(-)cv = 2.434 + (0.937 X HCO3(-)a), HCO3(-)cv = 2.093 + (0.942 X HCO3(-)a), HCO3(-)cv = 1.755 + (0.954 X HCO3 a), determination coefficient; 0.950, 0.925, 0.932 P values < 0.001 in each period. CONCLUSIONS: The acid base status of arterial blood is similar to that of central venous blood. Central venous blood gas values (pH, BE, HCO3(-)) may be an acceptable alternative to arterial blood gas values in kidney transplantation patients.

Treatment of Patients with Acute Type A Dissection with Malperfusion / 日本心臓血管外科学会雑誌

Although the results of surgical treatment for acute type A dissection have improved because of progress in surgical techniques, the prognosis is still very poor and optimal therapeutic approach is still not clearly established for cases of acute dissection complicated with malperfusion. Of 134 patients who presented with acute aortic dissection between January 1986 and June 1999, 57 had acute type A dissection and 10 had acute type A dissection with malperfusion. Patient age ranged from 53 to 78 (average, 64.6) years. There were 6 men and 4 women. There was accompanying cerebral ischemia in 3 cases, coronary ischemia in 1, visceral ischemia in 5, renal ischemia in 2, ischemia of the extremities in 7, and multiple organ ischemia in 5. One patient died before surgery, and another patient died after sternotomy due to aortic rupture. The other 8 patients underwent surgical operations. The following surgical procedures were performed: bypass grafting to the superior mesenteric artery was performed in 1 patient, stent implantation to the right coronary artery followed by ascending aortic replacement (19th day after onset) was performed in 1, and aortic repair (5 ascending aortic replacements and 1 hemiarch replacement) in the acute phase was performed in 6. The mortality rates were 66.7% (2/3) in patients with cerebral ischemia, 0% (0/1) in the patient with coronary ischemia, 80% (4/5) in those with visceral ischemia, 100% (2/2) in those with renal ischemia, 42.9% (3/7) in those with ischemia of the extremities, 80% (4/5) in those with multiple organ ischemia, and 50% (5/10) in all cases. All patients whose base excess (B.E.) was less than -10mEq/<i>l</i> on admission died (4/4). We conclude that in order to improve surgical results in patients with acute type A dissection with malperfusion, different approaches may be required for each patient. The combination of aortic repair and percutaneous reperfusion are important. Arterial blood gas analyses were simple, and the values of B. E. at admission were useful to determine the surgical strategy in these patients and to predict their prognosis.

The Predictors of the Change of Cardiac Output and the Changes of Electrolyte in the Acute Hemorrhagic Dogs / 대한마취과학회지

BACKGROUND: We designed this study to compare acid-base parameter with hemodynamic parameter as the predictor of acute blood loss. And we tried to evaluate the changes of electrolyte and to correlate the change of each parameter with that of cardiac output (CO) during acute blood loss. METHODS: Seven anesthetized (isoflurane 1.0-1.5%), paralyzed and mechanically constant ventilated dogs submitted to hemorrhage were studied. The dogs were hemorrhaged by progressive withdrawal of 50% of blood volume. After withdrawal of each 10% of blood volume mean arterial blood pressure (MAP), CO, arterial blood gas analysis, electrolytes and hematocrit (Hct) were measured. RESULTS: MAP, pH, PaCO2, PaO2 and base excess (BE) were decreased significantly according to hemorrhage and correlated with the percent decrease in CO. Serum sodium concentration and calcium concentration were not changed. Serum potassium concentration was increased and Hct was decreased significantly and correlated with the percent decrease in CO. Correlation between BE and percent decrease in CO (r=0.771) was superior to the correlations between any other parameter and percent decrease in CO. CONCLUSION: More negative BE is the best indicator of ongoing hemorrhage. Thus BE may be the best laboratory monitor of hemorrhage and the evaluation of acid-base state and the changes of serum potassium concentration are important in the acute hemorrhagic situation.

The Influence of isoflurane on systemic vascualr resistance during cardiopulmonary bypass / 대한마취과학회지

The influence of isoflurane on systemic vascular resistances was studied during total cardiopulmonary bypass with membrane oxygenator, low rate of 2.4 L/min/m(2) and moderate hypothermia Data were obtained from 40 adult patients undergoing corrective surgery for congenital or aquired heart disease. The materials were randomly divided in two groups with 20 and 20 patients, respectively, Before cadiopulmonary bypass, the same anesthetic technique was applied to 2 groups. During cardiapuhnonary bypass, isoflurane was given into oxygenator at 0.5-1.5% concentration in group I. In group II, no isoflurane was given but 0.2 mg/kg midazolam was supplied into the oxygenator at the beginning of bypass. To both groups small amounts of fentanyl were given during bypass. There were no significant differences in mean cardiopulmonary bypass time and pump flow between the groups.In group I, systemic vascular resistance did not increase until 60 minutes, whereas in group II systemic vascular resistance increased significantly after 30 minutes and maximal increase was noticed at 60 minutes. Data for base excess demonstrated that significant fall after 40 minutes of perfusion in group II, but not changes in group I. It is concluded that isoflurane exerts a beneficial vasodilatory action during caardiopulmonary bypass and hypothermia. And the harzards of local reduction in organic blood flow are ehminated, because an adequate perfusion pressure and flow are maintained by the heart lung machine.