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Indian patients undergoing cardiac surgery have different demographics, clinical profile as well as risk profile, compared to the western population. The purpose of this study was to validate the European System for Cardiac Operative Risk Evaluation (EuroSCORE) risk stratification model in Indian patients undergoing cardiac surgery in a single cardiac center. Data from 1000 consecutive adult patients undergoing cardiac surgery (coronary artery bypass grafting or valve surgery) were prospectively collected as per the EuroSCORE model. The model′s validity was assessed on the basis of its calibration power (Hosmer-Lemeshow test) and discriminatory power [area under receiver operating characteristic curve]. The patients were divided into three risk groups on the basis of their EuroSCORE. The Hosmer-Lemeshow test revealed a good calibration power (P = 0.73) and the area under the ROC curve was 0.8278, suggesting a good discriminative power. The predicted mortality was similar to observed mortality in low- and moderate-risk patients but the observed mortality in high-risk patients (15.6%) was double that of predicted mortality (7.5%). The risk factors prevalent in European population were not observed in Indian population. EuroSCORE accurately predicts mortality in low and moderate-risk Indian patients undergoing cardiac surgery but is less predictive for high-risk Indian patients. Updating and improvisation of EuroSCORE by incorporation of risk factors associated with rheumatic valvular heart disease which is more prevalent in India, may enable it to accurately predict mortality in high-risk patients also.

To determine the most effective dose regimen of aprotinin for infants undergoing arterial switch operation for transposition of the great arteries in reducing blood loss and postoperative packed red blood cell (PRBC) requirements. A total of 24 infants scheduled for arterial switch operation for transposition of the great arteries were included in the study. The infants were randomly assigned to one of the three groups. Group I (n = 8) patients received aprotinin in a dose of 20,000 kallikrein inhibiting units (KIU)/kg after induction of anesthesia, 20,000 KIU/kg was added to the pump prime, and 20,000 KIU/kg/hour infusion for three hours after weaning from bypass; group II (n = 8) patients received aprotinin 30,000 KIU/kg after induction of anesthesia, 30,000 KIU/kg was added to the pump prime and 30,000 KIU/Kg/hour infusion for three hours after weaning from bypass; group III patients (n = 8) received aprotinin 40,000 KIU/kg after induction of anesthesia, 40,000 KIU/kg was added to the pump prime and 40,000 KIU/kg/hour infusion for three hours after weaning from bypass. Postoperatively, the cumulative hourly blood loss and PRBC requirements were noted up to 24 hours from the time of admission in the intensive care unit (ICU). Use of blood and blood products were noted. Coagulation parameters such as hematocrit, activated clotting time (ACT), fibrinogen, prothrombin time (PT), international normalized ratio (INR), platelet count, and fibrin degradation products (FDP) were investigated before cardiopulmonary bypass (CPB), after protamine administration, and at four hours postoperatively in the ICU. The number of infants reexplored for increased mediastinal drainage was recorded. Renal functions were monitored by measuring urine output (hourly) and serum urea (mg%) and serum creatinine (mg%) at 24 hours. The sternal closure time was comparable in all the three groups. Cumulative blood loss (ml/kg/24 hours) was greatest in group I (17.30 ± 7.7), least in group III (8.14 ± 3.17), whereas in group II, it was 16.45 ± 6.33 (P = 0.019 group I versus group III; (P = 0.036 group II versus group III). Postoperative PRBC requirements were significantly less in high dose group III (P = 0.008, group I versus III; p = 0.116, group II versus group III) . Tests for coagulation performed at four hours postoperatively, viz. ACT, PT, INR, FDP, and platelets were comparable in the three groups. Urine output on CPB was comparable in all the groups. Serum urea and creatinine showed no significant difference between the three groups twenty four hours postoperatively. Aprotinin dosage regimen of 40,000 KIU/kg at induction, in CPB prime and postoperatively for three hours was most effective in reducing postoperative blood loss and PRBC transfusion requirements. Aprotinin does not have any adverse effect on renal function.

Traumatic diaphragmatic injury (DI) is a unique clinical entity that is usually occult and can easily be missed. Their delayed presentation can be due to the delayed rupture of the diaphragm or delayed detection of diaphragmatic rupture, making the accurate diagnosis of DI challenging to the trauma surgeons. An emergency laparotomy and thorough exploration followed by the repair of the defect is the gold standard for the management of these cases. We report a case of blunt DI in an elderly gentleman and present a comprehensive overview for the management of traumatic injuries of the diaphragm.

Takayasu Arteritis (TA) is a chronic inflammatory disease affecting large blood vessels, particularly the aorta and its branches, making it a type of vasculitis. It is reported to be highly prevalent in Southeast Asian countries. Clinical presentations may vary, including headache, weight loss, malaise, fever, hypertension, visual disturbances, and musculoskeletal symptoms. Gangrene is a rare manifestation of TA, with relatively few cases reported globally. If gangrene is present, it is commonly noted in the lower limbs. Inflammation of the blood vessels caused by TA might lead to stenosis of the affected vessels. The underlying pathophysiology of gangrene development in TA is poorly understood but is mainly attributed to the occlusion of blood vessels. It is associated with inflammatory markers produced by lymphocytes and macrophages. Immunosuppressive drugs are recommended for symptomatic relief. Early diagnosis and intervention can be useful in managing TA, preventing adverse outcomes, and reducing its financial, social, and psychological consequences. This is a case report of a 32-year-old female, presented with gangrene and a history of rheumatoid arthritis. Further examination revealed a presentation of TA. The patient was managed by below-knee amputation for gangrene of the left leg and medical management for TA. Therefore, authors aim to draw attention to the diagnosis of TA and the rare associated morbidity, ‘gangrene,’ and the importance of timely intervention.

Maintenance of sinus rhythm (SR) is superior to rate control in atrial fibrillation (AF). In order to achieve SR, we administered single-dose intravenous amiodarone intraoperatively and evaluated its effect on conversion of rheumatic AF to SR in patients undergoing valvular heart surgery. Patients were randomly assigned to amiodarone ( n = 42) or control ( n = 40) group in a double blind manner. The amiodarone group received amiodarone (3 mg/kg) intravenously prior to the institution of cardiopulmonary bypass and the control group received the same volume of normal saline. In the amiodarone group, the initial rhythm after the release of aortic cross clamp was noted to be AF in 14.3% ( n = 6) and remained so in 9.5% ( n = 4) of patients till the end of surgery. In the control group, the rhythm soon after the release of aortic cross clamp was AF in 37.5% ( n = 15) ( p = 0.035) and remained so in 32.5% ( n = 13) of patients till the end of surgery ( p = 0.01). At the end of first post-operative day 21.4% ( n = 9) of patients in amiodarone group and 55% ( n = 22) of patients in control group were in AF ( p = 0.002). The requirement of cardioversion/defibrillation was 1.5 (±0.54) in amiodarone group and 2.26 (±0.73) in the control group ( p = 0.014), and the energy needed was 22.5 (±8.86) joules in the amiodarone group and 40.53 (±16.5) in the control group ( p = 0.008). A single intraoperative dose of intravenous amiodarone increased the conversion rate of AF to normal sinus rhythm, reduced the need and energy required for cardioversion/defibrillation and reduced the recurrence of AF within one day.

We compared Aminocaproic acid with tranexamic acid, prospectively in 120 patients undergoing coronary artery bypass surgery on cardiopulmonary bypass. Patients were assigned to one of the 3 groups. Group A (n=40) did not receive any drug and acted as the control group. Group B (n=4) received aminocaproic acid 100 mg/kg each at anaesthetic induction, on bypass and after protamine reversal of heparin. group C (n=40) received tranexamic acid 10 mg/kg each at anaesthetic induction, on bypass and after protamine reversal of heparin. Postoperative blood loss at 24 hours, blood and blood product usage, and re-exploration rates were recorded, and tests for coagulation were performed at 6 hours postoperatively. It was found that blood loss in group A at 24 hours (780+/-120 mL) was significantly greater than Group B (360+/-90 mL) and Group C (215+/-70 mL). Plasma and platelet concentrate use in Group A (215+/-30 mL and 150+/-30 mL) was greater than Group B (190+/-20 mL and 75+/-30 mL) and Group C (185+/-20 mL and 80+/-30 mL). Re- explorations in Group A, 8/40 (20%) were greater than Group B, 2/40 (5%) and Group C, 2/40 (5%). Coagulation tests revealed better preservation of fibrinogen and lower levels of fibrin degradation products, in group B and C. These two groups were however statistically indistinguishable in respect to all the parameters studied, when compared with each other. It was concluded that both the antifibrinolytic agents in the doses studied were equally effective in reducing postoperative blood loss, blood and blood products usage and re-exploration rates. Coagulation parameters were better preserved as compared to the control group.

The current study was designed to investigate the consequences of rice cooking and soaking of cooked rice (CR) with or without arsenic (As) contaminated water on As and Fe (iron) transfer to the human body along with associated health risk assessment using additive main-effects and multiplicative interaction (AMMI) and Monte Carlo Simulation model. In comparison to raw rice, As content in cooked rice (CR) and soaked cooked rice (SCR) enhanced significantly (at p

Artificial Wisdom is advancement of Artificial Intelligence where wisdom should be recognized with the intelligence. Wisdom can be realized by adding values in the positive decisions. This is resulted in to the overall behavior of human being. Behavior can be demonstrated with the help of simulating thought process. Thoughts are generated in the mind along with the mental state. Mental state also known as mental factor is responsible for arousal of different types of thoughts. Ancient Indian cannon Abhidhamm claimed 52 mental factors. These are categorized in three classes such as Ethically Variable Factor, Unwholesome Factor and Beautiful Factor. Proposed computational model of consciousness demonstrates the classification of the mental states. Dataset consists of 445 samples collected from various respondents by asking three questions. Preprocessing is performed by using the techniques of Natural language processing and nonaxiomatic logic. Convolutional Neural Network Machine learning technique applied to classify the mental factors. Performance of the proposed system is measured by applying statistical measures such as Accuracy, Precision, Specificity, Recall and F1-Score. Accuracy for small and large database is obtained as 86.92% and 93.02% respectively.

Arsenic contamination in the rice agro-ecosystem, its consequent spread into the food chain, and its adverse impact are a global concern. However, assessment of the impact of arsenic contamination on the qualitative aspect of rice in the post-harvest phase has not been attempted. We laid down this particular experiment with the aim to assess how arsenic contamination influences the grain quality attributes and other elemental profiles of four popular rice varieties. The entire field study was conducted in the lower Indo-Gangetic plain from genotype (four) and environment (14 locations) interaction point of view, using the additive main effects and multiplicative interaction model. Our findings indicate that grain arsenic content can influence the grain quality attributes and other elemental profiles in a low to highly significant manner. Amylose content (r = 0.753), cooking time (r = 0.706), and gruel solid loss (r = 0.672, 0.721) were found to be positively correlated with grain arsenic content in high-yielding varieties. Noteworthy variations in micronutrient content like iron (6.63–9.23 mg kg−1), zinc (3.15–5.54 mg kg−1), and copper (2.04–3.86 mg kg−1) as well as soil properties are also visible. Moreover, indigenous rice varieties respond differently than high-yielding varieties. Besides these, a pronounced impact of gene/variety and environment interaction can be seen. The findings clearly indicate that the qualitative aspect of rice is also prone to As contamination. These outcomes will attract the attention of policy-makers and researchers to develop rice varieties that have desirable quality attributes appropriate for the arsenic-contaminated regions of the world for sustainable rice production.

Introduction: Rajyoga meditation is a form of mind body intervention that is promoted by the Brahma Kumaris World Spiritual University. This form of meditation can be easily performed without rituals or mantras and can be practiced anywhere at any time. The practice of Rajyoga meditation can have beneficial effects on modulating anxiety and cortisol level in patients undergoing major cardiac surgery. Materials and Methods: A prospective randomized control study was carried out in a single tertiary care center. One hundred and fifty patients undergoing elective coronary artery bypass surgery were enrolled in the study. The patients were randomized in two groups namely, Group 1 (Rajyoga group) and Group 2 (Control Group). Anxiety was measured on a visual analog scale 1–10 before the start of Rajyoga training or patient counseling (T1), on the morning of the day of surgery (T2), on the 2nd postoperative day (T3), and on the 5th postoperative day (T4). The serum cortisol level was measured in the morning of the day of surgery (T1), on the 2nd postoperative day (T2) and on the 5th postoperative day (T3), respectively. Results: In the study, it was seen that the anxiety level of the patients before the surgery (T1) and on the day of surgery (T2) were comparable between the two groups. However on the 2nd postoperative day (T3), the patients who underwent Rajyoga training had lower anxiety level in comparison to the control group (3.12 ± 1.45 vs. 6.12 ± 0.14, P < 0.05) and on the 5th postoperative day (T4) it was seen that Rajyoga practice had resulted in significant decline in anxiety level (0.69 ± 1.1 vs. 5.6 ± 1.38, P < 0.05). The serum cortisol level was also favorably modulated by the practice of Rajyoga meditation. Conclusion: Mindbody intervention is found to effective in reducing the anxiety of the patients and modulating the cortisol level in patients undergoing wellknown stressful surgery like coronary artery bypass surgery.

Artificial Wisdom is advancement of Artificial Intelligence where wisdom should be recognized with the intelligence. Wisdom can be realized by adding values in the positive decisions. This is resulted in to the overall behavior of human being. Behavior can be demonstrated with the help of simulating thought process. Thoughts are generated in the mind along with the mental state. Mental state also known as mental factor is responsible for arousal of different types of thoughts. Ancient Indian cannon Abhidhamm claimed 52 mental factors. These are categorized in three classes such as Ethically Variable Factor, Unwholesome Factor and Beautiful Factor. Proposed computational model of consciousness demonstrates the classification of the mental states. Dataset consists of 445 samples collected from various respondents by asking three questions. Preprocessing is performed by using the techniques of Natural language processing and nonaxiomatic logic. Convolutional Neural Network Machine learning technique applied to classify the mental factors. Performance of the proposed system is measured by applying statistical measures such as Accuracy, Precision, Specificity, Recall and F1-Score. Accuracy for small and large database is obtained as 86.92% and 93.02% respectively. [ABSTRACT FROM AUTHOR]

Parthenium hysterophorus L. is considered globally as one of the most troublesome weeds, which has invaded non-cropped as well as cropped lands in many tropical and sub-tropical countries including India. Biological control using the Mexican beetle (Zygogramma bicolorata Pallister) among other agents, has been considered most successful in India. In the present study, models were developed using climatic indices (minimum temperature, maximum temperature, rainfall and relative humidity) as independent variables to determine the suitable sites for the establishment of Z. bicolorata. Regression approach for model building revealed 79.6% concordance, 20.0% discordance, and 0.4% tie between predicted probabilities and observed responses whereas, decision tree using J48 algorithm classified 81.7% instances correctly which helped to frame the rules for predicting the establishment of Z. bicolorata. Based on these rules, it was concluded that a site experiencing climate with indices values of average minimum temperature 24.2–26.2 °C and rainfall 191.2–257.3 mm during July to October would be highly suitable for setting up the Z. bicolorata population in the region. These models might be useful to decide the most suitable sites for release and establishment of Z. bicolorata in India as well as in other parts of the world with similar climatic conditions. • Parthenium hysterophorus L. is one of the most troublesome weeds globally. • Biological control of P. hysterophorus using Zygogramma bicolorata Pallister has been considered most successful in India. • Regression approach and decision tree using J48 algorithm were used to model the establishment of beetle using climatic variables. •. Minimum temperature and its interaction with rainfall and relative humidity were found to be important climatic variables • These models might be useful for the selection of most suitable sites for release and establishment of Z. bicolorata. [ABSTRACT FROM AUTHOR]

Weeds are notorious yield reducers that are, in many situations, economically more harmful than insects, fungi or other crop pests. Assessment of crop yield and economic losses due to weeds in agriculture is an important aspect of study which helps in devising appropriate management strategies against weeds. A study was conducted to estimate the yield and economic losses due to weeds using the data from 1581 On-Farm Research trials conducted by All India Coordinated Research Project on Weed Management between 2003 and 14 in major field crops in different districts of 18 states of India. The study revealed that potential yield losses were high in case of soybean (50–76%) and groundnut (45–71%). Greater variability in potential yield losses were observed among the different locations (states) in case of direct-seeded rice (15–66%) and maize (18–65%). Three factors viz. location (state), crop, and soil type significantly (p < .0001) explained the variability in actual yield losses due to weeds at farmers’ fields. Significant differences were also observed between different locations, crops and soil types. Actual economic losses were high in the case of rice (USD 4420 million) followed by wheat (USD 3376 million) and soybean (USD 1559 million). Thus, total actual economic loss of about USD 11 billion was estimated due to weeds alone in 10 major crops of India viz. groundnut (35.8%), soybean (31.4%), greengram (30.8%), pearlmillet (27.6%), maize (25.3%), sorghum (25.1%), sesame (23.7%), mustard (21.4%), direct-seeded rice (21.4%), wheat (18.6%) and transplanted rice (13.8%). [ABSTRACT FROM AUTHOR]

Adsorption has proved to be an excellent way to treat industrial wastewater, due to its significant advantages like easy availability, inexpensive, ease of operation and highly efficient, compared to conventional expensive adsorbents like activated charcoal, alumina etc. The present investigation focused on utilization of Mangifera indica seed shell substrate for the removal of toxic heavy metals like Fe(II) and Mn(II) from wastewater. Mangifera indica seed shell substrate as an effective adsorbent was used for the first time for removal of Fe(II) and Mn(II) from aqueous solution. The adsorption isotherms were obtained in a batch reactor. Effect of various parameters like agitation time, pH, metal ion concentration, temperature, and doses of substrate were studied. It is evident that, the process of removal followed first order rate adsorption and the experimental data fitted well to Freundlich adsorption isotherm. The values of Freundlich isotherm parameter were between zero and one indicating favourable sorption for Fe(II) and Mn(II) metal ions. It shows good adsorption capacity towards Iron (II) and Manganese (II) at 30 min of optimum agitation time and at a pH of 4.5 even at low concentration. It effectively removed 81-82% of Fe(II) and Mn(II) in a single batch. It is also effective to remove heavy metal ions from single metal solutions as well as in the presence of other co- metal ions with the main metal of solution. This biosorbent can be successfully utilized for removal of toxic metals from industrial effluents, which could solve the problem of disposal of plant waste materials. [ABSTRACT FROM AUTHOR]

Objective The present study evaluates the feasibility, safety, and efficacy of edge-to-edge repair for moderate secondary/functional mitral regurgitation in patients undergoing aortic valve/root interventions. Methods Sixteen patients underwent transaortic edge-to-edge mitral valve repair. Mitral regurgitation was 2+ in 8 patients and 3+ in 6 patients. Two patients in whom cardiac arrest developed preoperatively had severe (4+) mitral regurgitation. Patients underwent operation for severe aortic regurgitation ± aortic root lesions. The mean left ventricular systolic and diastolic diameters were 51.5 ± 12.8 mm and 70.7 ± 10.7 mm, respectively. Left ventricular ejection fraction ranged from 20% to 60%. Primary surgical procedure included Bentall's ± hemiarch replacement in 10 patients, aortic valve replacement in 5 patients, and noncoronary sinus replacement with aortic valve repair in 1 patient. Results Severity of mitral regurgitation decreased to trivial or zero in 13 patients, 1+ in 2 patients, and 2+ in 1 patient. There were no gradients across the mitral valve in 9 patients, less than 5 mm Hg in 6 patients, and 9 mm Hg in 1 patient. There was no operative mortality. Follow-up ranged from 2 weeks to 54 months. Echocardiography showed trivial or no mitral regurgitation in 12 patients, 1+ in 2 patients, and 2+ in 2 patients. None of the patients had significant mitral stenosis. The mean left ventricular systolic and diastolic diameters decreased to 40.5 ± 10.3 mm and 58.7 ± 11.6 mm, respectively. Ejection fraction also improved slightly (22%-65%). Conclusions Transaortic edge-to-edge mitral valve repair is a safe and effective technique to abolish secondary/functional mitral regurgitation. However, its impact on overall survival needs to be studied. [ABSTRACT FROM AUTHOR]

Objectives The postoperative course following on-pump coronary artery bypass grafting (CABG) in patients with severe left ventricular (LV) systolic dysfunction is often unpredictable. Therefore, the aim of this study was to identify predictors of poor postoperative outcome in this subset of patients. Design Prospective observational study Setting Single university hospital Participants Forty patients with severe LV systolic dysfunction undergoing isolated on-pump CABG Interventions None Measurements and Main Results Comprehensive transesophageal echocardiographic examination was performed to obtain the indices of systolic and diastolic LV function after induction of anesthesia. A poor postoperative outcome was defined as patient death or vasoactive inotropic score≥20 for at least 6 hours and/or requiring intra-aortic balloon counterpulsation and/or mechanical ventilation for≥24 hours. Poor postoperative outcome was observed in 40% (16/40) of patients. Patients with poor postoperative outcomes had a significantly higher systolic dyssynchrony index, septal-lateral delay with a significantly lower global longitudinal strain and isovolumic acceleration, end-diastolic volume, end-systolic volume, and lateral and medial mitral annulus systolic velocity. In a binary logistic regression model, global longitudinal strain (odds ratio, 1.5, confidence interval [CI] 95%, 1.19-1.88, p = 0.001), septal-lateral delay (odds ratio, 1.02, 95% CI, 1.01-1.03; p = 0.001) and systolic dyssychrony index (odds ratio, 1.3, 95% CI, 1.13-1.48; p = 0.000) were found to be predictors of poor postoperative outcome. Conclusion Global longitudinal strain, systolic dyssynchrony index, and septal-lateral delay were reliable and accurate predictors of adverse outcomes in patients with severe LV systolic dysfunction undergoing on-pump CABG. [ABSTRACT FROM AUTHOR]

A 21-year-old patient with familial hypercholesterolemia presented with angina caused by ostial stenosis of the left internal mammary artery and severe calcific aortic stenosis with small aortic root 9 years after coronary revascularization. The ostium of the left internal mammary artery was enlarged using a saphenous vein patch through a left supraclavicular incision, which improved left ventricular function. Successful aortic valve replacement with posterior aortic root enlargement was subsequently performed. The surgical management of this condition is discussed briefly. [ABSTRACT FROM AUTHOR]

Background The standard surgical treatment of coarctation of the aorta is through a left posterolateral thoracotomy. However, when a concomitant cardiac procedure is required or the conventional approach is not possible or is hazardous, extraanatomic bypass to the supraceliac abdominal aorta may be advantageous. We discuss our technique and report the long-term results. Methods Between January 1986 and January 2015, 25 patients (16 males, 9 females) underwent extraanatomic bypass to the supraceliac abdominal aorta for various lesions of the arch and the descending thoracic aorta. Extraanatomic bypass to the supraceliac abdominal aorta was performed for patients in whom balloon dilatation was not feasible due to associated arch hypoplasia (n = 9), long-segment thoracic aorta narrowing due to nonspecific aortoarteritis (n = 3), or isolated long-segment coarctation of the aorta (n = 3). Patients who needed concomitant cardiac procedures, such as aortic valve replacement (n = 4), ascending aortic aneurysm repair (n = 2), or coronary artery bypass grafting (n = 1), and in whom balloon dilatation had failed, also underwent extraanatomic bypass to the supraceliac abdominal aorta. Extraanatomic bypass was also performed in 3 patients with recurrent coarctation after surgical repair and in whom balloon dilation was not feasible or unsuccessful. Results There were no early or late deaths. The peak-to-peak gradients between the upper limb and the lower limb decreased from 59.3 ± 16.3 mm Hg to 2.0 ± 2.8 mm Hg ( p < 0.0001). The mean follow-up was 96.6 ± 92.6 months (range, 1 to 240 months; median, 54 months). Doppler interrogation of the lower limb arterial system after a mean follow-up of 86.4 ± 85.2 months showed an unobstructed flow pattern. The ankle-brachial pressure index improved from a preoperative value of 0.60 ± 0.07 to 1.04 ± 0.11 ( p < 0.0001). Systolic blood pressure decreased significantly compared with preoperative values (153.9 ± 18.9 vs 122.8 ± 10.2, p < 0.0001). Three patients continued to receive antihypertensive medication due to persistent mild hypertension. Conclusions Extraanatomic bypass to the supraceliac abdominal aorta provides effective palliation for complex aortic obstructions. It is easy and quick to perform, avoids fatal complications, and is well tolerated in all age groups. [ABSTRACT FROM AUTHOR]

Background: The unique series arrangement of the cerebral and pulmonary circulation in bidirectional superior cavopulmonary anastomosis (BCPA) makes the pulmonary blood flow dependent upon the cerebral blood flow. Until now, several investigators have tried to correct post-BCPA hypoxemia with various methods such as induced hyperventilation, the addition of carbon dioxide, and inhaled nitric oxide with variable success rates. Methods: We prospectively studied 25 children with univentricular physiology undergoing BCPA surgery at 5 different time points in the preoperative (1 time point) and postoperative period (4 time points, each separated by at least 3 mm Hg changes in the superior vena cava [SVC] pressure). Intravenous fluids were administered in the postoperative period to raise the SVC pressure. Results: The systemic arterial oxygen saturation (Sao 2 ) increased significantly (p = 0.000) from a preoperative value of 80% ± 7% to 86% ± 7%, 91% ± 3% and 95% ± 4% at SVC pressures of 9 ± 1.6 mm Hg, 13 ± 1.3 mm Hg, and 16 ± 1.4 mm Hg, respectively, and then decreased to 94% ± 4% at SVC pressure of 20 ± 1.7 mm Hg. Systolic and diastolic blood pressure increased significantly and simultaneously with SVC pressure from 71 ± 8 mm Hg and 42 ± 6 mm Hg to 89 ± 11 mm Hg and 52 ± 7 mm Hg, respectively (p = 0.000). Conclusions: Administration of intravenous fluids improves the SVC pressure, possibly due to an increase in the cerebral blood flow and the SVC flow, and thus raises the arterial oxygen tension (Pao 2) and Sao 2. Each patient has a unique SVC pressure where the Sao 2 and the Pao 2 are maximum; beyond that limit, the Sao 2 does not improve. [Copyright &y& Elsevier]