Cardiac output (CO) and invasive hemodynamic measurements are useful during liver transplantation. The pulmonary artery catheter (PAC) is commonly used for these patients, despite the potential ...complications. Recently, a less invasive device (Vigileo/FloTrac) became available, which estimates CO using arterial pressure waveform analysis without external calibration. In this study, we compared CO obtained with a PAC using automatic thermodilution, instantaneous CO stat-mode (ICO(SM)), and CO obtained with the new device, arterial pressure waveform analysis (APCO) in patients undergoing liver transplantation.
Twenty sets of simultaneous measurements of APCO and ICO(SM) were determined in sedated and mechanically ventilated patients undergoing liver transplantation. Time points were as follows: after PAC insertion (T1-3), after portal clamping (T4-6), during anhepathy (T7-9), after graft reperfusion (T10-15), and in the postoperative period in the intensive care unit (T15-20).
We enrolled 20 patients and 400 measurements were obtained. No data were rejected. Bias between ICO(SM) and APCO was 0.8 L/min, 95% limits of agreement were -1.8 to 3.5 L/min. The percentage error was 43%. Bias between ICO(SM) and APCO was correlated with systemic vascular resistance r(2) = 0.55, P < 0.0001, y = 15.8-2.2 ln(x) and subgroup analysis revealed an increase in the bias and in the percentage error in patients with low systemic vascular resistance (Child-Pugh grade B and C patients). There was no difference between the different surgical periods.
Our results suggest that Vigileo/FloTrac CO monitoring data do not agree well with those of automatic thermodilution in patients undergoing liver transplantation, especially in Child-Pugh grade B and C patients with low systemic vascular resistance.
BACKGROUND:Mini-fluid challenge of 100 ml colloids is thought to predict the effects of larger amounts of fluid (500 ml) in intensive care units. This study sought to determine whether a low quantity ...of crystalloid (50 and 100 ml) could predict the effects of 250 ml crystalloid in mechanically ventilated patients in the operating room.
METHODS:A total of 44 mechanically ventilated patients undergoing neurosurgery were included. Volume expansion (250 ml saline 0.9%) was given to maximize cardiac output during surgery. Stroke volume index (monitored using pulse contour analysis) and pulse pressure variations were recorded before and after 50 ml infusion (given for 1 min), after another 50 ml infusion (given for 1 min), and finally after 150 ml infusion (total = 250 ml). Changes in stroke volume index induced by 50, 100, and 250 ml were recorded. Positive fluid challenges were defined as an increase in stroke volume index of 10% or more from baseline after 250 ml.
RESULTS:A total of 88 fluid challenges were performed (32% of positive fluid challenges). Changes in stroke volume index induced by 100 ml greater than 6% (gray zone between 4 and 7%, including 19% of patients) predicted fluid responsiveness with a sensitivity of 93% (95% CI, 77 to 99%) and a specificity of 85% (95% CI, 73 to 93%). The area under the receiver operating curve of changes in stroke volume index induced by 100 ml was 0.95 (95% CI, 0.90 to 0.99) and was higher than those of changes in stroke volume index induced by 50 ml (0.83 95% CI, 0.75 to 0.92; P = 0.01) and pulse pressure variations (0.65 95% CI, 0.53 to 0.78; P < 0.005).
CONCLUSIONS:Changes in stroke volume index induced by rapid infusion of 100 ml crystalloid predicted the effects of 250 ml crystalloid in patients ventilated mechanically in the operating room.
In mechanically ventilated patients, an increase in cardiac index during an end-expiratory-occlusion test predicts fluid responsiveness. To identify this rapid increase in cardiac index, continuous ...and instantaneous cardiac index monitoring is necessary, decreasing its feasibility at the bedside. Our study was designed to investigate whether changes in velocity time integral and in peak velocity obtained using transthoracic echocardiography during an end-expiratory-occlusion maneuver could predict fluid responsiveness.
This single-center, prospective study included 50 mechanically ventilated critically ill patients. Velocity time integral and peak velocity were assessed using transthoracic echocardiography before and at the end of a 12-sec end-expiratory-occlusion maneuver. A third set of measurements was performed after volume expansion (500 mL of saline 0.9% given over 15 minutes). Patients were considered as responders if cardiac output increased by 15% or more after volume expansion.
Twenty-eight patients were responders. At baseline, heart rate, mean arterial pressure, cardiac output, velocity time integral and peak velocity were similar between responders and non-responders. End-expiratory-occlusion maneuver induced a significant increase in velocity time integral both in responders and non-responders, and a significant increase in peak velocity only in responders. A 9% increase in velocity time integral induced by the end-expiratory-occlusion maneuver predicted fluid responsiveness with sensitivity of 89% (95% CI 72% to 98%) and specificity of 95% (95% CI 77% to 100%). An 8.5% increase in peak velocity induced by the end-expiratory-occlusion maneuver predicted fluid responsiveness with sensitivity of 64% (95% CI 44% to 81%) and specificity of 77% (95% CI 55% to 92%). The area under the receiver operating curve generated for changes in velocity time integral was significantly higher than the one generated for changes in peak velocity (0.96 ± 0.03 versus 0.70 ± 0.07, respectively, P = 0.0004 for both). The gray zone ranged between 6 and 10% (20% of the patients) for changes in velocity time integral and between 1 and 13% (62% of the patients) for changes in peak velocity.
In mechanically ventilated and sedated patients in the neuro Intensive Care Unit, changes in velocity time integral during a 12-sec end-expiratory-occlusion maneuver were able to predict fluid responsiveness and perform better than changes in peak velocity.
Purpose
: Continuous capnography should be used on patients admitted to post-anaesthesia care units (PACUs) with endotracheal tubes, but this monitoring is not always performed. Optimized ventilation ...in the PACU could be part of the global standards of practice to maintain the benefits of perioperative ventilation. The main objective was to study the rate of patients with alveolar hypoventilation before tracheal extubation or Laryngeal Mask Airway (LMA) removal upon the measurement of continuous capnography.
Methods
: In this prospective, parallel-group, randomized controlled study, we enrolled adult patients admitted to the PACU after general anaesthesia with an endotracheal tube or LMA in place. Patients were randomly assigned to two groups: in the Capno + group, nurses managed the patients with access to the capnometer and end-tidal carbon dioxide pressure (PETCO
2
) measurements; in the Capno- group, nurses monitored the patients without seeing PETCO
2
measurements. The primary outcome was the percentage of patients with PETCO
2
measurements above 45 mm Hg during the minute before extubation. Secondary endpoints included the delay in recovering spontaneous breathing, rate of hypoxemia, delay before extubation, and length of stay in the PACU.
Results
: Forty-eight patients were randomized into the two groups. The percentage of patients with PETCO
2
> 45 mm Hg the minute before extubation was significantly decreased in the Capno + group (83.3% versus 54,1% in the Capno- and Capno + groups respectively, p = 0.029). There were no significant differences concerning secondary endpoints.
Conclusions
: The use of PETCO
2
monitoring improves patient safety by decreasing the incidence of CO
2
retention during recovery from general anaesthesia. This study suggests that this monitoring should be integrated in the PACU. The risk of hypoxemia can also be prevented through the early recognition of apnoea.
Clinical Trial registry
: clinicaltrial.gov. identifier: NCT03370081
BACKGROUND:Lung recruitment maneuver induces a decrease in stroke volume, which is more pronounced in hypovolemic patients. The authors hypothesized that the magnitude of stroke volume reduction ...through lung recruitment maneuver could predict preload responsiveness.
METHODS:Twenty-eight mechanically ventilated patients with low tidal volume during general anesthesia were included. Heart rate, mean arterial pressure, stroke volume, and pulse pressure variations were recorded before lung recruitment maneuver (application of continuous positive airway pressure of 30 cm H2O for 30 s), during lung recruitment maneuver when stroke volume reached its minimal value, and before and after volume expansion (250 ml saline, 0.9%, infused during 10 min). Patients were considered as responders to fluid administration if stroke volume increased greater than or equal to 10%.
RESULTS:Sixteen patients were responders. Lung recruitment maneuver induced a significant decrease in mean arterial pressure and stroke volume in both responders and nonresponders. Changes in stroke volume induced by lung recruitment maneuver were correlated with those induced by volume expansion (r = 0.56; P < 0.0001). A 30% decrease in stroke volume during lung recruitment maneuver predicted fluid responsiveness with a sensitivity of 88% (95% CI, 62 to 98) and a specificity of 92% (95% CI, 62 to 99). Pulse pressure variations more than 6% before lung recruitment maneuver discriminated responders with a sensitivity of 69% (95% CI, 41 to 89) and a specificity of 75% (95% CI, 42 to 95). The area under receiver operating curves generated for changes in stroke volume induced by lung recruitment maneuver (0.96; 95% CI, 0.81 to 0.99) was significantly higher than that for pulse pressure variations (0.72; 95% CI, 0.52 to 0.88; P < 0.05).
CONCLUSIONS:The authors’ study suggests that the magnitude of stroke volume decrease during lung recruitment maneuver could predict preload responsiveness in mechanically ventilated patients in the operating room.
Augmented renal clearance (ARC) is recognized as a leading cause of β-lactam subexposure when conventional dosing regimens are used. The main objective was to compare the clinical outcome of ARC ...patients treated by conventional or increased β-lactam dosing regimens for a first episode of hospital or ventilator-acquired pneumonia (HAP-VAP).
In this single-center, retrospective study, every ARC patient treated by β-lactam for a first episode of HAP-VAP was included during two 15-month periods, before (Control period) and after (Treatment period) the modification of a local antibiotic therapy protocol. ARC was defined by a 24-h measured creatinine clearance ≥ 150 ml/min. The primary endpoint was defined as a therapeutic failure of the antimicrobial therapy or a HAP-VAP relapse within 28 days. Inverse probability of treatment weight (IPTW) was derived from a propensity score model. Cox proportional hazard models were used to evaluate the association between treatment period and clinical outcome.
During the study period, 177 patients were included (control period, N = 88; treatment period, N = 89). Therapeutic failure or HAP-VAP relapse was significantly lower in the treatment period (10 vs. 23%, p = 0.019). The IPTW-adjusted hazard ratio of poor clinical outcome in the treatment period was 0.35 (95% CI 0.15-0.81), p = 0.014. No antibiotic side effect was reported during the treatment period.
Higher than licensed dosing regimens of β-lactams may be safe and effective in reducing the rate of therapeutic failure and HAP-VAP recurrence in critically ill augmented renal clearance (ARC) patients.
General anesthesia in pregnant women can be associated with significant maternal and fetal morbidity. Emergency caesarean section can be performed by converting labor epidural analgesia to surgical ...anesthesia by injecting high-dose short-acting local anesthetics through the epidural catheter. The effectiveness and the delay to obtain surgical anesthesia depends upon the protocol used. Data indicate that alkalinization of local anesthetics may shorten their onset of action and increase their effectiveness. This study investigates whether alkalinization of adrenalized lidocaine could increase the efficacy and decrease the delay of onset of surgical anesthesia via an indwelling epidural catheter, thus decreasing the necessity to resort to general anesthesia for emergency caesarean deliveries.
This study will be a bicentric, double-blind, randomized, controlled trial with two parallel groups of 66 women who require emergency caesarian deliveries and who have been receiving epidural labor analgesia. The number of subjects in groups will be unbalanced with a 2:1 ratio of experimental:control. In both groups, all eligible patients will have had an epidural catheter placed for labor analgesia with levobupicaine or ropivacaine. Patient randomization will occur when the decision is made by the surgeon that an emergency caesarean delivery is indicated. Surgical anesthesia will be obtained by injecting 20 mL of 2% lidocaine with epinephrine 1:200,000, or 10 mL 2% lidocaine with epinephrine 1:200,000 plus 2 mL sodium bicarbonate 4.2% (total of 12 mL). The primary outcome will be the rate of conversion to general anesthesia for failure of the epidural to provide adequate analgesia. This study will be powered to detect a 50% reduction in the incidence of general anesthesia, from 80 to 40%, with a confidence ratio of 90%.
Sodium bicarbonate could be used to avoid general anesthesia for emergency caesarean deliveries by providing reliable and effective surgical anesthesia in women with pre-existing labor epidural catheters is promising. This randomized controlled trial seeks to determine the optimal local anesthetic mixture for converting epidural analgesia to surgical anesthesia for emergency caesarean sections. This may decrease the need for general anesthesia for emergency caesarian section, shorten the time to fetal extraction, and improve safety and patient satisfaction.
ClinicalTrials.gov NCT05313256. Registered on 6 April 2022.
The AMP-activated protein kinase agonist AICAR mimics a low intracellular energy state and inhibits the proliferation of cancer cells by different mechanisms, which may depend on the bioenergetic ...signature of these cells. AICAR can also stimulate mitochondrial biogenesis in myoblasts, neurons and HeLa cells. Yet, whether the reactivation of oxidative phosphorylation biogenesis by AICAR contributes to the growth arrest of cancer cells remains undetermined. To investigate this possibility, we looked at the impact of 24- and 48-hour treatments with 750
μM AICAR on human cancer cell lines (HeLa, DU145, and HEPG2), non-cancer cells (EM64, FM14, and HLF), embryonic cells (MRC5) and Rho
0 cells. We determined the bioenergetic profile of these cells and assessed the effect of AICAR on oxidative phosphorylation biogenesis, cell viability and cell proliferation, ROS generation, mitochondrial membrane potential and apoptosis induction. We also followed possible changes in metabolic regulators such as Akt and Hif1-α stabilization which might participate to the anti-proliferative effect of AICAR. Our results demonstrated a strong and cancer-specific anti-growth effect of AICAR that may be explained by three different modes according to cell type: the first mode included stimulation of the mitochondrial apoptotic pathway however with compensatory activation of Akt and upregulation of oxidative phosphorylation. In the second mode of action of AICAR Akt phosphorylation was reduced. In the third mode of action, apoptosis was activated by different pathways. The sensitivity to AICAR was higher in cells with a low steady-state ATP content and a high proliferation rate. This article is part of a Special Issue entitled: Bioenergetics of Cancer.
Display omitted
►The bioenergetic properties of tumors differ from normal tissue ones. ►Cancer cells are adapted to grow under hypoxia and aglycemia. ►The blockade of cancer cell's energy production could limit tumor growth. ►AICAR inhibits specifically cancer cell growth. ►Three Cell type dependent modes of action of AICAR were observed.
Background
Many maneuvers assessing fluid responsiveness (minifluid challenge, lung recruitment maneuver, end-expiratory occlusion test, passive leg raising) are considered as positive when small ...variations in cardiac index, stroke volume index, stroke volume variation or pulse pressure variation occur. Pulse contour analysis allows continuous and real-time cardiac index, stroke volume, stroke volume variation and pulse pressure variation estimations. To use these maneuvers with pulse contour analysis, the knowledge of the minimal change that needs to be measured by a device to recognize a real change (least significant change) has to be studied. The aim of this study was to evaluate the least significant change of cardiac index, stroke volume index, stroke volume variation and pulse pressure variation obtained using pulse contour analysis (ProAQT
®
, Pulsion Medical System, Germany).
Methods
In this observational study, we included 50 mechanically ventilated patients undergoing neurosurgery in the operating room. Cardiac index, stroke volume index, pulse pressure variation and stroke volume variation obtained using ProAQT
®
(Pulsion Medical System, Germany) were recorded every 12 s during 15-min steady-state periods. Least significant changes were calculated every minute.
Results
Least significant changes statistically differed over time for cardiac index, stroke volume index, pulse pressure variation and stroke volume variation (
p
< 0.001). Least significant changes ranged from 1.3 to 0.7% for cardiac index, from 1.3 to 0.8% for stroke volume index, from 10 to 4.9% for pulse pressure variation and from 10.8 to 4.3% for stroke volume variation.
Conclusion
To conclude, the present study suggests that pulse contour analysis is able to detect rapid and small changes in cardiac index and stroke volume index, but the interpretation of rapid and small changes of pulse pressure variation and stroke volume variation must be done with caution.
Neonatal and infant anaesthesia are associated with a high risk of perioperative complications. The aim of the current study was to describe those risks in France using the French data from the ...NECTARINE study.
Data from the French centres that participated to the NECTARINE study were analysed. The primary goal of the study was the description of patients’ characteristics, procedures and perioperative management and their comparison with the results of the European NECTARINE study. Secondary outcomes were the description of major perioperative complications and death.
Overall, 926 procedures collected in 15 centres (all teaching hospitals) were analysed. Comparison between the French and European NECTARINE cohorts found few differences related to patients’ characteristics and procedures. The rate of interventions for critical events (respiratory, haemodynamic, and metabolic) was similar between the two cohorts. Near-infrared spectroscopy monitoring was used in 12% of procedures. Nearly none of the thresholds for these interventions met the published standards. By day 30, complications (respiratory, haemodynamic, metabolic, renal, and liver failure) and death were observed in 14.4% 95% CI 11.6–16.4% and 1.8% 95% CI 1.1–2.9 of cases, respectively.
Although the health status of the patients in the French cohort was less severe, procedures, management and postoperative complications and mortality rates were similar to the European cohort. However, thresholds for interventions were often inadequate in both cohorts. Efforts should be undertaken to improve the knowledge and use of new monitoring devices in this population.
PDF
