Predictive value of Pv-aCO 2/Ca-vO 2 combined blood lactate concentration for primary peritonitis-related septic shock in children / 中华危重病急救医学

Objective:To investigate the prognostic value of the ratio of veno-arterial carbon dioxide partial pressure difference to arterio-venous oxygen content difference (Pv-aCO 2/Ca-vO 2) in children with primary peritonitis-related septic shock. Methods:A retrospective study was conducted. Sixty-three children with primary peritonitis-related septic shock admitted to department of intensive care unit of the Children's Hospital Affiliated to Xi'an Jiaotong University from December 2016 to December 2021 were enrolled. The 28-day all-cause mortality was the primary endpoint event. The children were divided into survival group and death group according to the prognosis. The baseline data, blood gas analysis, blood routine, coagulation, inflammatory status, critical score and other related clinical data of the two groups were statistics. The factors affecting the prognosis were analyzed by binary Logistic regression, and the predictability of risk factors were tested by the receiver operator characteristic curve (ROC curve). The risk factors were stratified according to the cut-off, Kaplan-Meier survival curve analysis compared the prognostic differences between the groups.Results:A total of 63 children were enrolled, including 30 males and 33 females, the average age (5.6±4.0) years old, 16 cases died in 28 days, with mortality was 25.4%. There were no significant differences in gender, age, body weight and pathogen distribution between the two groups. The proportion of mechanical ventilation, surgical intervention, vasoactive drug application, and procalcitonin, C-reactive protein, activated partial thromboplastin time, serum lactate (Lac), Pv-aCO 2/Ca-vO 2, pediatric sequential organ failure assessment, pediatric risk of mortality Ⅲ in the death group were higher than those in the survival group. Platelet count, fibrinogen, mean arterial pressure were lower than those in the survival group, and the differences were statistically significant. Binary Logistic regression analysis showed that Lac and Pv-aCO 2/Ca-vO 2 were independent risk factors affecting the prognosis of children [odds ratio ( OR) and 95% confidence interval (95% CI) were 2.01 (1.15-3.21), 2.37 (1.41-3.22), respectively, both P < 0.01]. ROC curve analysis showed that the area under curve (AUC) of Lac, Pv-aCO 2/Ca-vO 2 and their combination were 0.745, 0.876 and 0.923, the sensitivity were 75%, 85% and 88%, and the specificity were 71%, 87% and 91%, respectively. Risk factors were stratified according to cut-off, and Kaplan-Meier survival curve analysis showed that the 28-day cumulative probability of survival of Lac ≥ 4 mmol/L group was lower than that in Lac < 4 mmol/L group [64.29% (18/28) vs. 82.86% (29/35), P < 0.05]. Pv-aCO 2/Ca-vO 2 ≥ 1.6 group 28-day cumulative probability of survival was less than Pv-aCO 2/Ca-vO 2 < 1.6 group [62.07% (18/29) vs. 85.29% (29/34), P < 0.01]. After a hierarchical combination of the two sets of indicator variables, the 28-day cumulative probability of survival of Pv-aCO 2/Ca-vO 2 ≥ 1.6 and Lac ≥ 4 mmol/L group significantly lower than that of the other three groups (Log-rank test, χ2 = 7.910, P = 0.017). Conclusion:Pv-aCO 2/Ca-vO 2 combined with Lac has a good predictive value for the prognosis of children with peritonitis-related septic shock.

Progress on the relationship between hyperoxia exposure and renal development in premature infants / 国际儿科学杂志

Oxygen therapy is a common therapeutic method to improve oxygenation of premature infants, but long-term exposure to high oxygen can cause damage to immature organs and abnormal development.In addition to bronchopulmonary dysplasia and retinopathy, high oxygen levels will increase the risk of chronic kidney disease and hypertension in adulthood.High oxygen exposure can lead to kidney damage and developmental abnormalities in premature infants, including reduced number and increased volume of glomeruli, renal cell apoptosis, and abnormal development of renal tubules.The mechanism may be related to abnormal signaling pathways related to renal development.This article reviews the relationship between hyperoxia and kidney development and the possible mechanism of kidney disease, in an attempt to provide theoretical reference for early clinical intervention.

The prognostic value of PI combined with Pv-aCO 2 /Ca-vO 2 in patients with septic shock / 中华急诊医学杂志

Objective:To explore the predictive value of peripheral perfusion index (PI) combined with central venous-arterial carbon dioxide tension to arterial-venous oxygen content ratio(Pv-aCO 2/Ca-vO 2)for prognosis after initial resuscitation of septic shock. Methods:A total of 76 cases of patients with septic shock from January 2019 to January 2021 in emergency intensive care unit (EICU) of Harrson international peace hospital affiliated to Hebei Medical University were enrolled. All recovered according to 2016 Severe Sepsis and Septic Shock Treatment International Guidelines 2016 (SSC 2016) , and PI was monitored, central vein and arterial blood gas analysis was performed, and the ratio of Pv-aCO 2/Ca-vO 2 was calculated.The PI and Pv-aCO 2/Ca-vO 2 at 3 h,hemodynamic variables,oxygen metabolism indexes,APACHEⅡ and SOFA score were recorded.Patients were divided into survival group and death group according to 28 d survival condition, the dfferences in demographics and clinical data were compared between two groups.The Kaplan-Meier urviving curve was created and the survival of the patients was analyzed by the Log-rank test. Risk factors associated with the prognosis were analyzed using the Cox regression analysis. The role of PI and Pv-aCO 2/Ca-vO 2 in prediting death was evaluated by receiver operating characteristic curves(ROC). Results:There were 37 cases in survival group and 39 cases in death group.Compared with death group, PI in survival group [(1.77±0.63) vs. (0.89±0.69)]was significantly higher,and Pv-aCO 2/Ca-vO 2[(1.52±0.52) vs. (2.57±0.86)] was significantly lower ( P<0.05). Kaplan-Meier survival curve showed that the median survival time in the high PI group [20.09 d (95% CI:16.95-23.24) vs.11.00d (95% CI:7.14-14.86)] was longer than that in the low PI group(χ 2=12.424, P=0.000),and that in low Pv-aCO 2/Ca-vO 2 group [23.74 d (95% CI:20.35-27.13) vs.12.85d (95% CI:9.75-15.95)] was longer than that in the high Pv-aCO 2/Ca-vO 2 group (χ 2=12.200, P=0.000) .Cox regression analysis showed that both PI ( RR=0.397, 95% CI: 0.230-0.687, P =0.001) and Pv-aCO 2/Ca-vO 2 ( RR=1.878, 95% CI: 1.169-3.019, P =0.009) were predictors of 28 d mortality.The area under the ROC curve of PI and Pv-aCO 2/Ca-vO 2 for predicting 28 d death in patients with septic shock were 0.828 (95% CI: 0.732-0.923) and 0.785 (95% CI: 0.6777-0.893)respectively. The optimal cutoff values were 0.52 (sensitivity 58.3% and specificity 94.4%) and 0.35 (sensitivity 88.9% and specificity 63.9%)respectively, and the AUC of the combined prediction of the two indicators was 0.903 (95% CI: 0.835-0.971). Conclusions:Combination of PI and Pv-aCO 2/Ca-vO 2 is better to predict the risk of adverse outcomes of septie shock patients,and may provide useful information for the resuscitation at early stage.

Effect of venous-to-arterial carbon dioxide difference to arterial-to-venous oxygen content difference ratio combined with ultrasound on fluid resuscitation in critical patients with septic shock / 中国中西医结合急救杂志

Objective To observe the effect of venous-to-arterial carbon dioxide difference to arterial-to-venous oxygen content difference [(Pv-aCO2)/(Ca-vO2)] ratio combined with critical ultrasound during the phases of fluid resuscitation of critical patients with septic shock. Methods Ninety-two critical patients with septic shock admitted to department of intensive care unit (ICU) of Anji County People's Hospital from July 2016 to December 2017 were enrolled, and they were divided into study group (42 cases) and control group (50 cases) according to random number table method. Two groups of patients were given supportive treatment such as antibiotic therapy, vasoactive drugs to support blood pressure, mechanical ventilation (MV), transfusion and nutritional therapy. The fluid resuscitation in patients of control group was guided through monitoring central venous pressure (CVP) and lactic acid (Lac). Patients in study group were given (Pv-aCO2)/(Ca-vO2) ratio combined with critical ultrasound directed therapy on the basis of the monitoring method of the control group. The differences in heart rate (HR), mean arterial pressure (MAP), CVP, Lac, central venous oxygen saturation (ScvO2), (Pv-aCO2)/(Ca-vO2) ratio, dosage of noradrenalin (NE), fluid intake in 6 hours, sequential organ failure assessment (SOFA) of 24 hours, time of MV, length of ICU stay, 28-day mortality rate, and incidence of pulmonary edema were compared. The correlation between (Pv-aCO2)/(Ca-vO2) ratio and Lac in study group was analyzed by Spearman analysis. Results In two groups, the HR, Lac, and (Pv-aCO2)/(Ca-vO2) ratio were significantly lower after 6 hours of treatment than those at admission, and MAP, CVP and ScvO2 were significantly increased compared with those at admission (all P < 0.05). The Lac and (Pv-aCO2)/(Ca-vO2) ratio in study group were significantly lower than those in control group at 6 hours after fluid resuscitation [Lac (mmol/L): 4.1±2.2 vs. 4.6±2.3, (Pv-aCO2)/(Ca-vO2) ratio:0.7±0.2 vs. 0.8±0.3, both P < 0.05], and MAP, CVP and ScvO2 were higher than those in control group [MAP (mmHg, 1 mmHg = 0.133 kPa): 78.6±10.3 vs. 71.4±11.5, CVP (mmHg): 13.2±5.1 vs. 9.8±4.4, ScvO2: 0.73±0.08 vs. 0.70±0.08, all P < 0.05]. In study group, the dosage of NE, fluid intake in 6 hours, and incidence of pulmonary edema were less than those in control group [dosage of NE (μg·kg-1·min-1): 0.22±0.16 vs. 0.43±0.11, fluid intake in 6 hours (mL): 1 290±518 vs. 1 560±426, incidence of pulmonary edema: 19.05% (8/42) vs. 32.00% (16/50)], 24 hours SOFA declined (9.3±3.2 vs. 12.6±3.8), and time of MV and length of ICU stay were obviously shortened [time of MV (hours):70.48±8.65 vs. 88.35±10.37, length of ICU stay (days): 7.28±2.07 vs. 8.42±1.51, all P < 0.05]. The 28-day mortality in study group had a trend of decrease compared with that in control group [40.5 % (17/42) vs. 44% (22/50)], but there was no statistical significant difference between two groups (P > 0.05). There was a significant positive correlation between the (Pv-aCO2)/(Ca-vO2) ratio and Lac in study group (r = 0.532, P < 0.001). Conclusion (Pv-aCO2)/(Ca-vO2) ratio combined with critical ultrasound can better guide the volume management of critical patients with septic shock, reduce the usage of vasoactive drugs and incidence of pulmonary edema, and decrease the time of MV and length of ICU stay.

Effect of different solute solutions on hydrogen producing rate of hydrogen rods / 军事医学

Objective To investigate the hydrogen production rate of hydrogen rods in different solute solutions ,and to study the correlations between hydrogen and oxygen concentrations in the solution and the relationships between hydrogen and oxidation-reduction potential .Methods The hydrogen rich solution was produced using metal magnesium to react with water.The experiment was divided into NaCl , Na2SO3, Na2SO4, CH3COOH, and CH3COONa solution groups, respectively, with 0％, 0.2％, 0.9％and 3％in different concentration solutions .The hydrogen content of the corresponding solution was determined at 0, 2, 4, 6, 8, and 10 h.Moreover, the oxygen content in the solution , redox potential and pH value were simultaneously determined .Results Within the same reaction time , the higher concentration of NaCl , the higher the hydrogen production rate .The amount of hydrogen in the solution was negatively correlated with that of oxygen ( R2 =0.9306).The higher the hydrogen content, the lower the oxygen content.With the amount of hydrogen in the solution increasing, oxidation was reduced while pH was increased.The hydrogen-producing rate of hydrogen rods in different solute solutions was the highest with Na2SO3,followed by NaCl and Na2SO4(P<0.05 or P<0.01).In the acetic acid solution, the hydrogen-producing rate of rods was significantly higher than in the sodium salt solution (P<0.05).The hydrogen content increased gradually with time .The oxygen concentration was significantly lower than in the sodium salt solution ( P <0.05), and the oxygen content decreased over time .Conclusion The type and concentration of solutes in solutions and the oxygen content and acidity of a solution have significant influence on the hydrogen -producing rate of hydrogen rods. Therefore, by adjusting the type and concentration of solutes in the solution, we can prepare different types of hydrogen concentration solutions , which can provide detailed reference parameters for hydrogen production of hydrogen rods in clini -cal and practical applications.

Clinical Observation of Milrinone in the Treatment of Persistent Pulmonary Hypertension of Newborn / 中国药房

OBJECTIVE:To observe clinical efficacy and safety of milrinone in the treatment of persistent pulmonary hyperten-sion of newborn. METHODS:52 newborns with persistent pulmonary hypertension were divided into control group and observa-tion group according to random number table,with 26 cases in each group. The control group were given mechanical ventilation and intravenous prostaglandin therapy. Observation group was treated with Milrinone injection at loading dose of 50 μg/kg,10 min intravenous injection,maintenance dose of 0.75 μg/(kg·min). Both groups received treatment for 48 h. Clinical efficacies of 2 groups were compared as well as SpO2,PaO2,OI,PAP,PAMP and SV before and after treatment. The occurrence of ADR was compared between 2 groups. RESULTS:Total effective rate of observation group was 92.31%,which was significantly higher than 80.77% of control group,with statistical significance (P0.05). After treatment,above indexes of 2 groups were im-proved significantly;SpO2,PaO2,OI and SV levels of observation group were significantly higher than those of control group, while PAP and PAMP levels were significantly lower than those of control group,with statistical significance(P<0.05). No obvi-ous ADR was found in 2 groups. CONCLUSIONS:Milrinone shows significant therapeutic efficacy in the treatment of persistent pulmonary hypertension of newborn,and can significantly improve persistent pulmonary hypertension and increased oxygen con-tent of blood with good safety.

Preliminary study of cerebral oxygen metabolism and change of blood lactate in early stage of sepsis in rats / 中华急诊医学杂志

Objective To observe the change of cerebral oxygen metablism and the level of blood lactate in early stage of sepsis in rats.Method Sixty-four SD rats were randomly(random number)divided into septic group and control group.The sepsis model of rat was made by lipopolysaccharide (LPS,10 mg/kg)injected intra-abdominally,and rats of control group were treated with the same amount of physiological saline instead.And each group was further divided into 4 sub-groups of4 h,6 h,12 h and 24 h after treatment.At each interval,blood samples were obtained via jugular vein for detecting blood oxygen saturation (Sjv02)and blood lactate(LA).The blood oxygen saturation(Sa02)of ventral aorta was also measured.Arteriovenous oxygen content difference (AVD02) and oxygen extraction fraction (OEF) were studied.These four variables were analyzed and compared between two groups.Results The AVD02 and OEF in sepsis group were higher than those in control groups of 3 h,6 h and 12 h (P0.05).LA in sepsis group was higher than that in control group in each interval (P<0.05).Conclusions In early stage of sepsis,cerebral perfusion,cerebral oxygen supply and cerebral oxygen extraction increase.The global oxygen metabolic variables(Sjv02,AVD02 and OEF)and the level of LA can be used to objectively and accurately evaluate the cerebral oxygen metabolic dysfunction in early stage of sepsis.

Discrimination of hemoglobin-effects on arterial-to-jugular bulb oxygen content differences according to arterial carbon dioxide tension

BACKGROUND: Arterial jugular bulb oxygen content differences (AJVDO2) can be related to cerebral blood flow and oxygen consumption. Plasma Hb has been reported to have both-sided effect on AJVDO2. Increased Hb increases oxygen content in artery and jugular bulb, and the net effect is to reduce AJVDO2. Moreover, increasing Hb raises blood viscosity, and could increase AJVDO2. This study was designed to discriminate the Hb-effects on AJVDO2 mathematically. METHODS: Sixty adults were enrolled in this study. General anesthesia and mechanical ventilation were administered. A normocapnic and a subsequent hypocapnic state were achieved. Paired data including 1/AJVDO2, PaCO2, Hb, mean arterial pressure, temperature and anesthetic concentration were recorded during each state. Nonlinear mixed-effects model was applied to fit 1/AJVDO2 using PaCO2 and Hb as covariates. RESULTS: The 1/AJVDO2 was well modeled by PaCO2 and Hb using a three-parameter logistic function: predicted 1/AJv DO2 = 0.38713 / 1+e(31.20981-PaCO2)/25.94210-1.45162xHb The increase in PaCO2 raised the 1/AJVDO2 sigmoidally (P < 0.0001) and its slope was affected by Hb (P = 0.0022). The transition point of the Hb-effect was PaCO2 = 31.20981 (SEM 1.519201). Intraclass correlation coefficient was estimated at 0.9973. CONCLUSIONS: Our finding suggests that the Hb-effect on 1/AJVDO2 is both-sided; the viscosity-effect is dominant at low levels of PaCO2 and effect of oxygen content is dominant at high levels of PaCO2

Effect of Combined Hyperventilation and Mannitol on Cerebral Blood Flow and Cerebral O2 Metabolism during a Craniectomy / 대한마취과학회지

BACKGROUND: There are therapies to lower intracranial pressure (ICP) including head elevation, hyperventilation, diuretics injection, intravenous mannitol, hypothermia, cerebrospinal fluid drainage, and cerebral resection in neurosurgical patients. However in recent reports, hyperventilation followed by mannitol administration may lead to cerebral ischemia. Therefore, we investigated the effect of 0.5-1.0 g/kg mannitol administration on jugular venous oxygen saturation (SjVO2) and cerebral arterial- jugular venous oxygen content difference (AVDO2) at PaCO2 25-30 mmHg and 35-40 mmHg in patients undergoing neurosurgery. METHODS: We studied 17 patients undergoing neurosurgery in the Ajou University Hospital. Anesthesia was induced with fentanyl, midazolam, thiopental, and vecuronium, and maintained with O2-Air-Isoflorane, a continuous infusion of fentanyl, and vecuronium. Patients were divided into two groups. Group 1 (n = 10) which is PaCO2 25-30 mmHg and Group 2 (n = 7) which is PaCO2 35-40 mmHg by controlling ventilator. Measurements of SjVO2 and AVDO2 in following time intervals: I = preinjection of mannitol, II = postinjection 20 minutes of mannitol, III = postinjection 40 minutes of mannitol were obtained for each group. 0.5-1.0 g/kg mannitol was administered intravenously just at duramater opening. RESULTS: Hemodynamics and hematologics were not significantly different among the two groups. SjVO2 of each group are as follows; Group 1; I (70.3+/-8.1%), II (66.3+/-6.9%), III (69.1+/-7.9%) and Group 2; I (78.6+/-7.4%), II (75.1+/-8.1%), III (76.0+/-11.2%). Hyperventilation significantly decreased SjVO2. AVDO2 was not significantly different but SjVO2 in II was significantly decreased compared with I and III in Group 1 (20% patients). CONCLUSIONS: Mannitol produced a change of SjVO2 and AVDO2 during hyperventilation. Therefore, intravenous mannitol during hyperventilation should be given cautiously according to the patients status because it may cause cerebral ischemia in critical patients.

The Effects of Intravenous Thiopental Injection on Jugular Venous Oxygen Saturation (SjVO2) during Cerebral Aneurysm Surgery / 대한마취과학회지

BACKGROUND: Thiopental has a profound impact on the cardiovascular system. The effects of hemody namics after intravenous thiopental on the balance of cerebral metabolism with cerebral blood flow is unknown. The purpose of this study was to monitor hemodynamic change, cerebral arterial-jugular venous oxygen content difference (AVDO2) and jugular venous oxygen saturation (SjVO2) after a thiopental injection for brain protection during cerebral aneurysm surgery. METHODS: Twenty patients received a standard anesthetic consisting of isoflurane, vecuronium and fentanyl with a PaCO2 of 30 35 mmHg. Hemodynamics, arterial and jugular venous blood gases were measured at 3 time points:I; Just before thiopental injection; II; Electroencephalographic (EEG) burst suppression after a 4 5 mg/kg intravenous thiopental injection; and III; EEG recovery. RESULTS: Intravenous thiopental (4 5 mg/kg) induced an EEG burst suppression for 6.5 +/- 1.7 minutes. Hemodynamics and arterial blood gas analysis were not significantly different among the different time points, but mean arterial pressure (68.4 +/- 7.2 mmHg) and systemic vascular resistance (1027.0 +/- 300.9 dynes sec/cm5) in II were significantly (P < 0.05) decreased compared with I (84.3 +/- 9.6, 1169.1 +/- 304.5) and III (89.1 +/- 10.6, 1288.6 +/- 426.1). SjVO2 (71.6 +/- 11.8%) was significantly (p < 0.05) decreased within the normal value compared with I (75.1 +/- 5.6) and III (76.1 +/- 10.1), but AVDO2 was not significantly different among the 3 time points. There was no evidence of cerebral ischemia or infarction in computed tomographic (CT) findings of the 20 patients after surgery. CONCLUSIONS: Hemodynamics after 4 5 mg/kg intravenous thiopental do not modify the balance ofcerebral oxygen metabolism with cerebral blood flow in patients undergoing cerebral aneurysm surgery.

Crystalloid Resuscitation in Experimental Hemorrhagic Shock in Dogs / 대한마취과학회지

Although crystalloid solutions such as Ringer's lactate have become the standard for initial volume replacement after hemorrhage, it is controversy whether this fluid alone restores and maintains the depressed physiologic function after severe hemorrhage. Six anesthetized dogs were bled(35ml/kg) and resuscitated with Ringers lactate solution (100 ml/kg). Physiologic variables are measured initialy, after hemorrhage, after resucitation. Compared with initial value, after resuscitation data show marked reduction in hemoglobin, oxygen carrying capacity, vascular resistance, and electrolyte. But cardiac output and blood gas analysis data was not changed. Prothrombin time and partial thromboplastin time was prolongated. From this study crystalloid resuscitation in severe hemorrhagic shock restore cardiac output and perfusion, but fail to maintain adequate oxygen carrying capacity.

Noninvasive monitoring technology and device for tissue blood oxygen content / 医疗卫生装备

The conventional invasive tissue blood oxygen content measurement is poor in continuity.The weakness of the signal,strong interference and random transmission of the photon in tissues make the measurement difficult.Recently,near infrared spectrum technology has been applied to tissue blood oxygen content measurement.This paper presents a hardware design method for tissue blood oxygen content measurement by near infrared spectrum technology.

The Changes of Blood Lactate Concentrations during Open - heart Sugery / 대한마취과학회지

During anesthesia and surgery, body homeostasis and tissue oxygen demand/supply balance is disrupted and blood lactate concentration in increased. We have studied the changes of blood lactate concentrations and arterial, venous oxygen contents during open heart surgery in 15 patients. Samplings were done at 1) before anesthetic induction, 2) after induction, 3) after sternotomy, 4) onset of cardiopulmonary bypass, 5) duing hypothermic cardiopulmonary bypass, 6) after cardiopulmonary bypass and 7) after operation. Blood lactate concentrations were inereased signifieantly at the onset of, during and after cardiopulmonary bypass and after operation(p<0.001). Arterial oxygen contents were decreased significantly at the onset of, during and after cardiopulmonary bypass(p<0.05). Venous oxygen contents were decreased significantly at the during and after cardiopulmonary bypass and after operation(p<0.05). There were significant negative correlations between arterial, venous oxygen contents and blood lactate concentrations. Changes of venous oxygen saturation, mean arterial pressure and pH had not significant relationships with the lactate concentrations.

Comparison of the Cerebral Arterio - Venous Oxygen Content Differences ( AVDO2 ) during Isoflurane and Neurolept Anesthesia for Aneurysmal Surgery / 대한마취과학회지

In 30 patients subjected to craniotomy for cerebral aneurysm, the correlation of cerebral blood flow and cerebral metabolism were evaluated by measuring mean arterial pressure (MAP) and cerebral arterio-venous oxygen content differences(AVDO2) during isoflurane and neurolept anesthesia. 15 patients were given 1 MAC isoflurane anesthesia and 15 patients neurolept anesthesia. MAP, AVDO2 and PaCO2 were measured before skin incision, after skin incision, after opening of dura and after closing of dura. The results were as follows: 1) In both groups, significant increases in MAP was observed after skin incision(P<0.05), no significant difference between the two groups was found. 2) In both groups, significant decreases in AVDO2 was observed after skin incision (<0.05), AVDO, values showed insignificant difference. The results indicate that even moderate increases in MAP after skin incision during isoflurane and neurolept anesthesia affect AVDO2 values, suggesting increases in cerebral blood flow. Therefore measures that prevent increase in MAP during incision should be implemented. The study suggests that isoflurane anesthesia is as useful as neurolept anesthesia in terms of AVDO2 to patients undergoing aneurysmal surgery.

Change of Internal Jugular Venous Oxygen Content during Hypotension in Halothane and Isoflurane Anesthesia / 대한마취과학회지

Autoregulation of cerebral blood flow is altered by volatile anesthetics and vasodilators such as nitroglycerin. Forty patients with cerebral aneurysm were anesthetized with halothane or isoflurane, and hypotension (mean arterial pressure: 55 mmHg) was induced with nitroglycerin. Blood gas analysis of radial artery and internal jugular vein during normotension and hypotension was performed. The results were as follows 1) There were no significant changes in juqular venous oxygen saturation, difference of arterial and venous oxygen content and extration rate of oxygen between normotension and hypotension. 2) There were no differences in SjvO2, CaO2, CjvO2, and O2ER between halothane and isoflurane. There is no possibility of cerebral ischemia in induced hypotension by nitroglycerin during halothane and isoflurane anesthesia.

Changes of Oxygen Content in Alveolar Arterial Blood in Patients with Chronic Obstructive Pulmonary Diseases / 第三军医大学学报

Blood gas analysis was performed in 65 normal adults, 90 patients with chronic bronchitis and 173 with cor pulmonale. Altogether 401 determinations were done. It was found that the P(A-a)O2 was significantly higher in patients with chronic bronchitis and cor pulmonale than in normal adults. When considered comprehensively with the parameters of pulmonary ventilation and diffusion functions and the ventilation/perfusion ratio, P(A-a)O2 possesses definite clinical significance. In various kinds of acid-base disturbance, P(A-a)O2 is the highest in decompensatory respiratory acidosis, and the lowest in compensatory respiratory acidosis.