Change in the optic nerve sheath diameter after deflation of a pneumatic tourniquet: a prospective observational study

Applying a pneumatic tourniquet provides surgeons with a bloodless surgical field. However, application of the tourniquet induces various physiological changes. We evaluated the effect of tourniquet deflation on the intracranial pressure by using ultrasonography to measure the optic nerve sheath diameter (ONSD) in patients undergoing lower limb surgery. The ONSD was measured in 20 patients at five time points: after anesthetic induction (T0) and immediately before (T1), immediately after (T2), 5 min after (T3), and 10 min after tourniquet deflation (T4). Hemodynamic and respiratory variables were recorded. The ONSD showed significant differences at each point (P < 0.001). The ONSDs at T2 and T3 were significantly greater than that at T1 (P = 0.0007 and < 0.0001, respectively). The change in the end-tidal carbon dioxide partial pressure (EtCO2) was similar to the change in the ONSD. The change in the ONSD was significantly correlated with the change in the EtCO2 after tourniquet deflation (r = 0.484, P = 0.030). In conclusion, the ONSD, as an indicator of intracranial pressure, increased after tourniquet deflation in patients undergoing lower limb surgery. This was correlated with an increased EtCO2 and arterial carbon dioxide partial pressure.Trial registration: ClinicalTrials.gov (NCT03782077).

Estimation of Partial Pressure of CO2 (pCO2) Around Mount Krakatau waters, Sunda Straits, Indonesia

The study aimed to develop the formula and validation the value of oceanic carbon dioxide partial pressure (pCO2sea) around Krakatau Waters in the Sunda Strait using parameters such as sea surface temperature (SST), sea surface salinity (SSS), and chlorophyll-a (Chl). Using observation data from different seasons (September 2017 and April 2018) The formulation of the empirical equation by using a multivariate polynomial regression method. The results of the study show that the empirical equation for estimating the pCO2 sea is as follows: : pCO2= -472.069+1044.043x log(SST) -435.897xlog(SSS) -5.03xlog (Chl).This formula can be applied for both seasons. The results of the analysis of the T-student test and p-value showed a strong relationship between the SST parameters and pCO2 with a correlation of 0.91 then followed by salinity with a correlation of -0.82. Whereas chlorophyll-a holds a weak proportion with a correlation of 0.32. The increase in SST accelerates the solubility of CO2 from atmosphere to the sea thereby increasing CO2 sea concentration and increasing pCO2 sea. While the increase in salinity and chlorophyll-a only gives a weak effect

Cerebral and Systemic Stress Parameters in Correlation with Jugulo-Arterial CO2 Gap as a Marker of Cerebral Perfusion during Carotid Endarterectomy

Intraoperative stress is common to patients undergoing carotid endarterectomy (CEA); thus, impaired oxygen and metabolic balance may appear. In this study, we aimed to identify new markers of intraoperative cerebral ischemia, with predictive value on postoperative complications during CEA, performed in regional anesthesia. A total of 54 patients with significant carotid stenosis were recruited and submitted to CEA. Jugular and arterial blood samples were taken four times during operation, to measure the jugulo-arterial carbon dioxide partial pressure difference (P(j-a)CO2), and cortisol, S100B, L-arginine, and lactate levels. A positive correlation was found between preoperative cortisol levels and all S100B concentrations. In addition, they are positively correlated with P(j-a)CO2 values. Conversely, postoperative cortisol inversely correlates with P(j-a)CO2 and postoperative S100B values. A negative correlation was observed between maximum systolic and pulse pressures and P(j-a)CO2 after carotid clamp and before the release of clamp. Our data suggest that preoperative cortisol, S100B, L-arginine reflect patients’ frailty, while these parameters postoperatively are influenced by intraoperative stress and injury. As a novelty, P(j-a)CO2 might be an emerging indicator of cerebral blood flow during CEA.

Intelligent Monitoring of Care Status for COPD Patients Based on Deep Learning

To discuss the application method and effect of COPD patients in deep learning in intelligent monitoring, two groups were used under a reasonable selection of antibiotics specifically including reasonable and effective oxygen administration, atomization, sputum discharge treatment, psychotherapy, and rehabilitation training and treatment. Results were indicated, and there were significant differences between the lung function evaluation index and the two groups. Its intelligent monitoring mode was 97.5% and 80.0%, while the red blood cell ratio, arterial oxygen partial pressure (PaO2), pulse blood oxygen saturation (SpO2), arterial carbon dioxide partial pressure (PaCO2), and symptom improvement were better than artificial and were statistically significant ( P < 0.05 ). Therefore, the training of the anti-inspiratory muscle can effectively improve the lung function and dyspnea symptoms of COPD patients at the stable stage, thus greatly improving their respiratory function and ensuring the quality of life of patients, which is worthy of clinical application.

Abstract 10679: Tissue-to-Arterial Carbon Dioxide Partial Pressure Gradient as a Useful Measure for Monitoring Tissue Perfusion in a Pig Model of Hemorrhagic Shock and Resuscitation

Introduction: Transcutaneous CO 2 (tcPCO 2 ) and arterial CO 2 (artPCO 2 ) become decoupled during shock. Aim: To test the hypotheses the gradient between tcPCO 2 and artPCO 2 (tc-artPCO 2 ) can be an early, sensitive measure to detect inadequate tissue perfusion in a pig model of hemorrhage shock. Methods: Six female pigs were used. A transcutaneous monitor was attached to the ear for measuring transcutaneous O 2 (tcPO 2 ) and tcPCO 2 . Pulmonary artery catheter and the pulse index continuous cardiac output (PiCCO) were instrumented for monitoring a variety of hemodynamic parameters. To induce massive hemorrhagic shock, blood was withdrawn stepwisely. Then, animals were resuscitated in stages with transfusions of the stored blood. The parameters were measured at the timings of 10, 20, and 30 ml/kg of blood withdrawals and the completions of 10, 20, and 30 ml/kg of blood transfusion . Levels of systemic oxygen delivery (DO 2 ) were also calculated at all measurement points. Results: Hemorrhage and blood transfusion impacted hemodynamic and laboratory data, such as cardiac output (CO), stroke volume, MAP, heart rate, pulmonary artery wedge pressure, global end-diastolic volume, hemoglobin, and arterial lactate. The tc-artPCO 2 markedly increased as CO decreased ( Figure A ). The critical level of DO 2 (DO 2crit ) was defined as 11.72 ml/kg/min according to tcPO 2 (a threshold as 30 mmHg). There was significant correlation between tc-artPCO 2 and DO 2 (r = -0.83, P<.0001). ROC analyses revealed that the AUCs to predict DO 2crit for tc-artPCO 2 , shock index (SI), and lactate were 0.94 (95% CI, 0.87-1.00), 0.78 (0.63-0.93), and 0.65 (0.47-0.82), respectively. The AUC for tc-artPCO 2 was greater with respect to the prediction of DO 2crit than for SI (P<.05) ( Figure B ). Conclusions: The tc-artPCO 2 strongly correlated with CO and DO 2 during hemorrhage shock and resuscitation. The less-invasive tc-artPCO 2 monitoring can sensitively detect systemic inadequate O2 supply in hemorrhagic shock.

Monitoring the tissue perfusion during hemorrhagic shock and resuscitation: tissue-to-arterial carbon dioxide partial pressure gradient in a pig model

Background Despite much evidence supporting the monitoring of the divergence of transcutaneous partial pressure of carbon dioxide (tcPCO2) from arterial partial pressure carbon dioxide (artPCO2) as an indicator of the shock status, data are limited on the relationships of the gradient between tcPCO2 and artPCO2 (tc-artPCO2) with the systemic oxygen metabolism and hemodynamic parameters. Our study aimed to test the hypothesis that tc-artPCO2 can detect inadequate tissue perfusion during hemorrhagic shock and resuscitation. Methods This prospective animal study was performed using female pigs at a university-based experimental laboratory. Progressive massive hemorrhagic shock was induced in mechanically ventilated pigs by stepwise blood withdrawal. All animals were then resuscitated by transfusing the stored blood in stages. A transcutaneous monitor was attached to their ears to measure tcPCO2. A pulmonary artery catheter (PAC) and pulse index continuous cardiac output (PiCCO) were used to monitor cardiac output (CO) and several hemodynamic parameters. The relationships of tc-artPCO2 with the study parameters and systemic oxygen delivery (DO2) were analyzed. Results Hemorrhage and blood transfusion precisely impacted hemodynamic and laboratory data as expected. The tc-artPCO2 level markedly increased as CO decreased. There were significant correlations of tc-artPCO2 with DO2 and COs (DO2: r = − 0.83, CO by PAC: r = − 0.79; CO by PiCCO: r = − 0.74; all P < 0.0001). The critical level of oxygen delivery (DO2crit) was 11.72 mL/kg/min according to transcutaneous partial pressure of oxygen (threshold of 30 mmHg). Receiver operating characteristic curve analyses revealed that the value of tc-artPCO2 for discrimination of DO2crit was highest with an area under the curve (AUC) of 0.94, followed by shock index (AUC = 0.78; P < 0.04 vs tc-artPCO2), and lactate (AUC = 0.65; P < 0.001 vs tc-artPCO2). Conclusions Our observations suggest the less-invasive tc-artPCO2 monitoring can sensitively detect inadequate systemic oxygen supply during hemorrhagic shock. Further evaluations are required in different forms of shock in other large animal models and in humans to assess its usefulness, safety, and ability to predict outcomes in critical illnesses.

Scale Squeeze Inhibitor as Preventive Treatment in Brani Wells, Offshore North West Java

The Brani-Field is located offshore Northwest Java and currently produces hydrocarbons from a sandstone reservoir with an average watercut of 83%. Some high watercut wells are prone to scale problems and need repetitive clean outs to overcome production decline. In 2019, downhole scale inhibitor treatment was evaluated and planned for application in these wells. Scale inhibitors are able to prevent the formation of scale so the well is able to deliver higher average oil production with lower intervention cost. In Brani wells, scale deposits are formed in perforations, downhole completion equipment, and flowlines depending on the water composition, temperature, and a reduction in dissolved carbon dioxide partial pressure. These scales deposits restrict the fluid flow causing significant production loss. In extreme conditions, the production tubing was blocked completely with the scale deposits and cease the production. Normally, the scale restriction problem in Brani wells were handled by a combination of mechanical and acidizing treatment using Coiled Tubing (CT) for downhole completion and acidizing treatment for flowline restrictions. These treatment were performed periodically every 2-4 months depending on well conditions with scaling becoming more severe in higher watercut wells. From an economic standpoint, current scale treatment methods lead to very high well intervention costs due to expensive liftboat and CT unit daily rates. The economics of these conventional treatments is further deterred by low yearly average oil production. Evaluation for scale inhibitor treatment started with the candidate selection, fluids compatibility test, core re-gain permeability test, and economic evaluation. BRG-10 well was selected as first candidate due to scale problem severity and low oil production rate. This well normally delivers 140 bopd with 90% watercut, but scale build up in the tubing and flowline prevented the fluids flow and lowered the production to 30 bopd in just two months. Laboratory test results demonstrated that the core regained permeability with the main pill fluids to a relatively high, 77.96% without any fluids compatibility issues. Deployment of a scale inhibitor squeeze treatment in BRG-10 well was executed in Jan 2020 by bullheading 657 bbl inhibitor fluids into the formation. The well was then shut in for 24 hours of soaking time. The post treatment results showed a very promising result with much more stable oil production after 11 months treatment, welltest on December 2020 showed the well was still producing 130 bopd with 90% watercut. Following the successful application in BRG-10, the scale inhibitor treatment was applied in other wells, BRK-7 in June 2020 and BRG-5L in August 2020. So far, those two wells show good production performance with 93 bopd with 85% watercut for BRK-7 and 264 bopd with 76% for BRG-5L.

Effect of Surgical Masks on Cardiopulmonary Function in Healthy Young Subjects: A Crossover Study

Objective: Mask plays an important role in preventing infectious respiratory diseases. The influence of wearing masks in physical exercise on the human body needs to be studied. The purpose of this study is to explore the influence of wearing surgical masks on the cardiopulmonary function of healthy people during exercise.Methods: The physiological responses of 71 healthy subjects (35 men and 36 women, age 27.77 ± 7.76 years) to exercises with and without surgical masks (mask-on and mask-off) were analyzed. Cardiopulmonary function and metabolic reaction were measured by the cardiopulmonary exercise test (CPET). All tests were carried out in random sequence and should be completed in 1 week.Results: The CPETs with the mask-on condition were performed undesirably (p &lt; 0.05), and the Borg scale was higher than the mask-off (p &lt; 0.001). Rest oxygen uptake (V.O2) and carbon dioxide production (V.CO2) with the mask-on condition were lower than mask-off (p &lt; 0.01), which were more obvious at peak exercise (V.O2peak: 1454.8 ± 418.9 vs. 1628.6 ± 447.2 ml/min, p &lt; 0.001; V.CO2peak: 1873.0 ± 578.7 vs. 2169.9 ± 627.8 ml/min, p = 0.005), and the anaerobic threshold (AT) brought forward (p &lt; 0.001). At different stages of CPET with the mask-on condition, inspiratory and expiratory time (Te) was longer (p &lt; 0.05), and respiratory frequency (Rf) and minute ventilation (V.E) were shorter than mask-off, especially at peak exercise (Rfpeak: 33.8 ± 7.98 vs. 37.91 ± 6.72 b/min, p &lt; 0.001; V.Epeak: 55.07 ± 17.28 vs. 66.46 ± 17.93 l/min, p &lt; 0.001). VT was significantly lower than mask-off just at peak exercise (1.66 ± 0.45 vs. 1.79 ± 0.5 l, p &lt; 0.001). End-tidal oxygen partial pressure (PetO2), end-tidal carbon dioxide partial pressure (PetCO2), oxygen ventilation equivalent (V.E/V.O2), and carbon dioxide ventilation equivalent (V.E/V.CO2) with mask-on, which reflected pulmonary ventilation efficiency, were significantly different from mask-off at different stages of CPET (p &lt; 0.05), but no significant difference in percutaneous oxygen saturation (SpO2) was found. Differences in oxygen pulse (V.O2/HR), oxygen uptake efficiency slope (OUES), work efficiency (△V.O2/△W), peak heart rate (HR), and peak systolic blood pressure (BP) existed between two conditions (p &lt; 0.05).Conclusion: Wearing surgical masks during aerobic exercise showed certain negative impacts on cardiopulmonary function, especially during high-intensity exercise in healthy young subjects. These results provide an important recommendation for wearing a mask at a pandemic during exercises of varying intensity. Future research should focus on the response of wearing masks in patients with related cardiopulmonary diseases.

Discussion on Nursing Mode of Ecmo in Treating Severe Patients

Objective: To evaluate the nursing effect of Ecmo treatment for severe patients.Methods :66 patients treated with extracorporeal membrane pulmonary oxygenation were included in the experimental data. From August 2018 to August 2019, the patients were divided into experimental group and reference group by random digital table method, each group was 33 cases. Routine nursing and targeted nursing were performed to compare the complications of the two groups.Results :(1) The correlation index of extracorporeal membrane pulmonary oxygenation treatment before treatment was consistent, P>0.05, the oxygen saturation and oxygen partial pressure of 2 h、4h after treatment in the experimental group were higher than those in the reference group, compared with the reference group, the carbon dioxide partial pressure of 2 h、4h after treatment in the experimental group was lower, showing statistical significance of data test (PP>0.05). (2) The incidence of infection, bleeding, coagulation, embolism and hypotension in the experimental group (12.12%) was lower than that in the reference group (45.45%), showing statistical significance (P<0.05).Conclusion: the specific nursing effect of extracorporeal membrane pulmonary oxygenation in severe patients can effectively improve the success rate of treatment, and the possibility of complications during treatment is low.