Comparison of thromboelastographic profiles in pediatric patients with congenital heart disease according to existence of cyanosis.

PURPOSE: Congenital heart disease (CHD) is divided into two groups according to cyanosis status. Cyanotic CHD has a low level of systemic oxygenation and is accompanied by increased erythropoiesis. We hypothesized that pediatric patients with CHD would exhibit different thromboelastographic profiles according to their cyanosis status. METHODS: The study recruited 70 pediatric patients younger than 12 months who were undergoing surgery for CHD. Patients were allocated to the acyanotic group or cyanotic group after preoperative evaluations of their diagnosis and peripheral oxygen saturation in the operating room on room air. After inducing anesthesia, blood samples were collected. Hematologic and thromboelastographic profiles were evaluated. RESULTS: Demographic data were similar between groups. The thromboelastographic profiles did not differ significantly between the groups. Hematologic profiles generally did not significantly differ between groups, except hematocrit (Hct) was higher in the cyanotic group (41.7 ± 6.8% vs. 35.3 ± 5.3%, p < 0.001). In patients under 3 months of age, prothrombin time (PT) (cyanotic group 15.4 ± 1.1 s vs. acyanotic group 14.2 ± 2.4 s, p = 0.02) and international normalized ratio (INR) (cyanotic group 1.24 ± 0.12 vs. acyanotic group 1.12 ± 0.27, p = 0.01) were significantly greater in the cyanotic group. CONCLUSION: There were no differences in thromboelastographic profiles between the patients with or without cyanosis, regardless of age. The Hct was higher in the cyanotic group in patients under 12 months, while the PT was prolonged and the INR was increased in the cyanotic group in patients under 3 months.

Noninvasive Urine Oxygen Monitoring and the Risk of Acute Kidney Injury in Cardiac Surgery.

BACKGROUND: Acute kidney injury (AKI) is a common complication of cardiac surgery. An intraoperative monitor of kidney perfusion is needed to identify patients at risk for AKI. The authors created a noninvasive urinary oximeter that provides continuous measurements of urinary oxygen partial pressure and instantaneous urine flow. They hypothesized that intraoperative urinary oxygen partial pressure measurements are feasible with this prototype device and that low urinary oxygen partial pressure during cardiac surgery is associated with the subsequent development of AKI. METHODS: This was a prospective observational pilot study. Continuous urinary oxygen partial pressure and instantaneous urine flow were measured in 91 patients undergoing cardiac surgery using a novel device placed between the urinary catheter and collecting bag. Data were collected throughout the surgery and for 24 h postoperatively. Clinicians were blinded to the intraoperative urinary oxygen partial pressure and instantaneous flow data. Patients were then followed postoperatively, and the incidence of AKI was compared to urinary oxygen partial pressure measurements. RESULTS: Intraoperative urinary oxygen partial pressure measurements were feasible in 86/91 (95%) of patients. When urinary oxygen partial pressure data were filtered for valid urine flows greater than 0.5 ml · kg-1 · h-1, then 70/86 (81%) and 77/86 (90%) of patients in the cardiopulmonary bypass (CPB) and post-CPB periods, respectively, were included in the analysis. Mean urinary oxygen partial pressure in the post-CPB period was significantly lower in patients who subsequently developed AKI than in those who did not (mean difference, 6 mmHg; 95% CI, 0 to 11; P = 0.038). In a multivariable analysis, mean urinary oxygen partial pressure during the post-CPB period remained an independent risk factor for AKI (relative risk, 0.82; 95% CI, 0.71 to 0.95; P = 0.009 for every 10-mmHg increase in mean urinary oxygen partial pressure). CONCLUSIONS: Low urinary oxygen partial pressures after CPB may be associated with the subsequent development of AKI after cardiac surgery.

Author Correction: Assessment of the effects of sugammadex on coagulation profiles using thromboelastographic parameters.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Assessment of the effects of sugammadex on coagulation profiles using thromboelastographic parameters.

This study evaluated the effects of sugammadex at conventional doses of 2 and 4 mg/kg on the coagulation profile by analyzing thromboelastographic parameters and performing a traditional laboratory coagulation analysis. A total of 100 patients undergoing arthroscopic shoulder surgery were enrolled. The patients were randomly divided into the 2 mg and 4 mg groups. The laboratory coagulation test and thromboelastographic analysis were performed before and 15 min after administering sugammadex. Prothrombin time (PT) was significantly prolonged after sugammadex administration than before it in intragroup comparisons of the 2 mg group (12.8 ± 0.6 s vs. 13.6 ± 0.7 s, p < 0.001) and the 4 mg group (13.0 ± 0.5 s vs. 13.7 ± 0.5 s, p < 0.001). R time, derived from thromboelastography, was also significantly prolonged after sugammadex administration (4.7 ± 1.8 min vs. 5.8 ± 2.1 min, p = 0.005). In conclusion, the conventional doses of 2 or 4 mg/kg sugammadex prolonged PT. Sugammadex 4 mg/kg also prolonged R time, although the value was within the normal range. Therefore, physicians should be cautious with the higher sugammadex dose, particularly in patients with a high risk of bleeding because the higher dose was associated with less coagulation.Trial registration: KCT0002133 (https://cris.nih.go.kr).

Deep neuromuscular blockade during spinal surgery reduces intra-operative blood loss: A randomised clinical trial.

BACKGROUND: Spinal surgery is usually performed in the prone position using a posterior approach. However, the prone position may cause venous engorgement in the back and thus increase surgical bleeding with interruption of surgery. The prone position also affects cardiac output since large vessels are compressed decreasing venous return to the heart. OBJECTIVE: We hypothesised that deep neuromuscular blockade would be associated with less surgical bleeding during spinal surgery in the prone position. DESIGN: Randomised, single blinded trial. SETTING: University teaching hospital. PARTICIPANTS: Eighty-eight patients in two groups. INTERVENTIONS: Patients were randomly assigned to moderate neuromuscular blockade or deep neuromuscular blockade. In the moderate neuromuscular blockade group, administration of rocuronium was adjusted such that the train-of-four count was one to two. In the deep neuromuscular blockade group, rocuronium administration was adjusted such that the train-of-four count was zero with a posttetanic count 2 or less. MAIN OUTCOME MEASURES: The primary outcome was the volume of intra-operative surgical bleeding. The surgeon's satisfaction with operating conditions, haemodynamic and respiratory status, and postoperative pain scores were evaluated. RESULTS: The median [IQR] volume of intra-operative surgical bleeding was significantly less in the deep neuromuscular blockade group than in the moderate neuromuscular blockade group; 300 ml [200 to 494] vs. 415 ml [240 to 601]; difference: 117 ml (95% CI, 9 to 244; P = 0.044). The mean ±â€ŠSD surgeon's satisfaction with the intra-operative surgical conditions was greater in the deep neuromuscular blockade group than in the moderate neuromuscular blockade group; 3.5 ±â€Š1.0 vs. 2.9 ±â€Š0.9 (P = 0.004). In intergroup comparisons of respiratory variables, peak inspiratory pressure was lower in the deep neuromuscular blockade group overall (P < 0.001). The median [IQR] postoperative pain score was lower in the deep neuromuscular blockade group than the moderate neuromuscular blockade group; 50 [36 to 60] vs. 60 [50 to 70], (P = 0.023). CONCLUSION: Deep neuromuscular blockade reduced intra-operative surgical bleeding in patients undergoing spinal surgery. This may be related to greater relaxation in the back muscles and lower intra-operative peak inspiratory pressure when compared with moderate neuromuscular blockade. TRIAL REGISTRATION: KCT0001264 (http://cris.nih.go.kr).

Comparison of the expression of cluster of differentiation (CD)39 and CD73 between propofol- and sevoflurane-based anaesthesia during open heart surgery.

High expression of cluster of differentiation (CD)39 and CD73 has cardio-protective effects. We hypothesised that the expression of CD39 and CD73 would differ between propofol- and volatile anaesthetic-based anaesthesia in patients undergoing open heart surgery (OHS). The objective of this prospective randomized trial was to compare the changes in CD39 and CD73 levels in CD4+ T cells between propofol- and sevoflurane-based anaesthesia during OHS. The study randomly allocated 156 patients undergoing OHS to a propofol or sevoflurane group. Blood was obtained preoperatively and up to 48 hours after weaning from cardiopulmonary bypass (CPB). The expression levels of CD39 and CD73 in circulating CD4+ T cells, serum cytokines and other laboratory parameters were analysed. The primary outcome was the expression of CD39 and CD73 on CD4+ T cells. Demographic data and perioperative haemodynamic changes did not show significant differences between the two groups. The expression of CD39 and CD73 in the sevoflurane group was significantly lower than in the propofol group (P < 0.001). Other laboratory findings including cardiac enzymes and cytokine levels, did not show significant intergroup differences. Propofol attenuated the decrease in CD39 and CD73 in circulating CD4+ T cells compared to sevoflurane-based anaesthesia during OHS.

The Correlation between the Change in Thoracic Fluid Content and the Change in Patient Body Weight in Fontan Procedure.

BACKGROUND: The thoracic fluid content (TFC) and its percent change compared to the baseline (TFCd0%) derived from a bioreactance technique using a noninvasive cardiac output monitoring (NICOM) device correlate well with the amount of fluid removal in patients undergoing hemodialysis and with intraoperative fluid balance in pediatric patients undergoing cardiac surgery. We hypothesized that TFC or TFCd0% would also be a useful indicator allowing fluid management in pediatric patients undergoing a Fontan procedure. METHODS: The medical records of patients who underwent an elective Fontan procedure were reviewed retrospectively. The intraoperative variables recorded at two time points were used in the analysis: when the NICOM data obtained just after anesthesia induction (T0) and just before transfer of the patient from the operating room to the ICU (T1). The analyzed variables were hemodynamic parameters, TFC, TFCd0%, stroke volume variation, body weight gain, change in the central venous pressure, and difference in the TFC (ΔTFC). RESULTS: The correlation coefficient between TFCd0% and body weight gain was 0.546 (p = 0.01); between TFCd0% and body weight gain% 0.572 (p = 0.007); and between TFCd0% and intraoperative fluid balance 0.554 (p = 0.009). The coefficient of determination derived from a linear regression analysis of TFCd0% versus body weight gain was 0.30 (p = 0.01); between TFCd0% and body weight gain% 0.33 (p = 0.007); and between TFCd0% and intraoperative fluid balance 0.31 (p = 0.009). CONCLUSIONS: TFCd0% correlated well with body weight gain, body weight gain%, and intraoperative fluid balance. It is a useful indicator in the intraoperative fluid management of pediatric patients undergoing a Fontan procedure. TRIAL REGISTRATION: This trial is registered with Clinical Research Information Service KCT0002062.

Postoperative Delirium in Patients Undergoing Off-Pump Coronary Artery Bypass Grafting According to the Anesthetic Agent: A Retrospective Study.

OBJECTIVE: To evaluate the effect of two anesthetic agents (sevoflurane or propofol) on postoperative delirium (POD) in patients undergoing off-pump coronary artery bypass grafting (CABG). DESIGN: Retrospective observational design. SETTING: University hospital. PARTICIPANTS: Two hundred ninety-two patients undergoing off-pump CABG who were anesthetized with sevoflurane or propofol. METHODS: Incidence of POD, laboratory data, and pre-, intra-, and 24-hour postoperative clinical variables were reviewed retrospectively. The independent predictors of POD were evaluated. MEASUREMENTS AND MAIN RESULTS: The cumulative incidence of POD after off-pump CABG was 10.6% (31 of 292 patients) and the incidence rates of POD were not statistically significant in the sevoflurane and propofol groups (13% [20 of 156 patients] and 8% [11 of 136 patients], respectively; p = 0.137). Other variables, including the laboratory and clinical data also did not differ significantly between the anesthetic groups. Age ≥75 years (odds ratio [OR], 4.84; 95% confidence interval [CI], 1.44-16.27; p = 0.011), postoperative pneumonia (OR, 10.84; 95% CI, 3.32-35.34; p < 0.001), 6 or more packed red blood cell units transfusion in the first 24 hours postoperatively (OR, 5.30; 95% CI, 1.32-21.27; p = 0.019), and 24-hour postoperative albumin <3.0 g/dL (OR, 3.38; 95% CI, 1.20-9.31; p = 0.021) were independent predictors of POD after off-pump CABG. CONCLUSIONS: The incidence of POD in patients undergoing off pump-CABG did not differ between those receiving sevoflurane versus propofol-based anesthesia.

Reversal with sugammadex for rocuronium-induced deep neuromuscular block after pretreatment of magnesium sulfate in rabbits.

BACKGROUND: Magnesium sulfate (MgSO4) has been used in the treatment of pre-eclampsia, hypertension and arrhythmia. Magnesium enhances the neuromuscular block of rocuronium. This study has been conducted to evaluate the reversal efficacy of sugammadex from deep rocuronium-induced neuromuscular block (NMB) during consistent pretreatment of MgSO4 in rabbits. METHODS: Twenty-eight rabbits were randomly assigned to four groups, a control group or study groups (50% MgSO4 150-200 mg/kg and 25 mg/kg/h IV), and received rocuronium 0.6 mg/kg. When post-tetanic count 1-2 appeared, sugammadex 2, 4, and 8 mg/kg was administered in the 2-mg group, control and 4-mg group, and 8-mg group, respectively. The recovery course after reversal of sugammadex administration was evaluated in each group. RESULTS: The mean serum concentration of magnesium was maintained at more than 2 mmol/L in the study groups, and the total dose of MgSO4 was more than 590 mg. The reversal effect of sugammadex on rocuronium-induced NMB in pretreated MgSO4 was not different from that in the group without MgSO4. The recovery time to train-of-four ratio 0.9 after sugammadex administration in the 2-mg group was longer than in the other groups (P < 0.001); there were no other significant differences among the groups. CONCLUSIONS: The reversal of sugammadex from a deep rocuronium-induced NMB during large pretreatment of MgSO4 was not affected. However, we should consider that the reversal effect of sugammadex varied depending on the dose.

Diagnosis Accuracy of Mean Arterial Pressure Variation during a Lung Recruitment Maneuver to Predict Fluid Responsiveness in Thoracic Surgery with One-Lung Ventilation.

Background. Lung recruitment maneuver (LRM) during thoracic surgery can reduce systemic venous return and resulting drop in systemic blood pressure depends on the patient's fluid status. We hypothesized that changes in systemic blood pressure during the transition in LRM from one-lung ventilation (OLV) to two-lung ventilation (TLV) may provide an index to predict fluid responsiveness. Methods. Hemodynamic parameters were measured before LRM (T0); after LRM at the time of the lowest mean arterial blood pressure (MAP) (T1) and at 3 minutes (T2); before fluid administration (T3); and 5 minutes after ending it (T4). If the stroke volume index increased by >25% following 10 mL/kg colloid administration for 30 minutes, then the patients were assigned to responder group. Results. Changes in MAP, central venous pressure (CVP), and stroke volume variation (SVV) between T0 and T1 were significantly larger in responders. Areas under the curve for change in MAP, CVP, and SVV were 0.852, 0.759, and 0.820, respectively; the optimal threshold values for distinguishment of responders were 9.5 mmHg, 0.5 mmHg, and 3.5%, respectively. Conclusions. The change in the MAP associated with LRM at the OLV to TLV conversion appears to be a useful indicator of fluid responsiveness after thoracic surgery. TRIAL REGISTRATION: This trial is registered at Clinical Research Information Service with KCT0000774.

Impact of effect-site concentration of propofol on cardiac systolic function assessed by tissue Doppler imaging.

OBJECTIVE: To evaluate the relationship between effect-site concentration (CE) of propofol during total intravenous anaesthesia (TIVA) and cardiac systolic function using tissue Doppler imaging (TDI) in patients undergoing cardiovascular procedures. METHODS: Stepwise increments of CE of propofol of 1.0, 2.0, 3.0 and 4.0 µg/ml (modified Marsh model) were achieved using a target-controlled infusion device. Transthoracic echocardiographic assessments using TDI were performed for each CE of propofol and corresponding systolic myocardial velocity (s'), mean arterial blood pressure (MAP), heart rate (HR) and bispectral index (BIS) were evaluated. RESULTS: Data from 31 patients were analysed in this prospective study. The s' velocity decreased with increasing propofol CE and values recorded at propofol CE 3.0 and 4.0 µg/ml were near or below 8 cm/s indicating abnormal cardiac systolic function. MAP, HR and BIS also decreased with each propofol CE increment. CONCLUSION: Although the recommended dosage for propofol is up to 4.0 µg/ml, caution should be taken when using propofol concentrations above 2.0 µg/ml during TIVA in patients with underlying cardiovascular diseases.

Effect of Mechanical Ventilation Mode Type on Intra- and Postoperative Blood Loss in Patients Undergoing Posterior Lumbar Interbody Fusion Surgery: A Randomized Controlled Trial.

BACKGROUND: The aim of study was to evaluate the effect of mechanical ventilation mode type, pressure-controlled ventilation (PCV), or volume-controlled ventilation (VCV) on intra- and postoperative surgical bleeding in patients undergoing posterior lumbar interbody fusion (PLIF) surgery. METHODS: This was a prospective, randomized, single-blinded, and parallel study that included 56 patients undergoing PLIF and who were mechanically ventilated using PCV or VCV. A permuted block randomization was used with a computer-generated list. The hemodynamic and respiratory parameters were measured after anesthesia induction in supine position, 5 min after patients were changed from supine to prone position, at the time of skin closure, and 5 min after the patients were changed from prone to supine position. The amount of intraoperative surgical bleeding, fluid administration, urine output, and transfusion requirement were measured at the end of surgery. The amount of postoperative bleeding and transfusion requirement were recorded every 24 h for 72 h. RESULTS: The primary outcome was the amount of intraoperative surgical bleeding, and 56 patients were analyzed. The amount of intraoperative surgical bleeding was significantly less in the PCV group than that in the VCV group (median, 253.0 [interquartile range, 179.0 to 316.5] ml in PCV group vs. 382.5 [328.0 to 489.5] ml in VCV group; P < 0.001). Comparing other parameters between groups, only peak inspiratory pressure at each measurement point in PCV group was significantly lower than that in VCV group. No harmful events were recorded. CONCLUSION: Intraoperative PCV decreased intraoperative surgical bleeding in patients undergoing PLIF, which may be related to lower intraoperative peak inspiratory pressure.

Effects of sevoflurane increments on left ventricular systolic long-axis performance during sevoflurane-remifentanil anesthesia for cardiovascular surgery.

BACKGROUND: The direct impact of sevoflurane on intraoperative left ventricular (LV) systolic performance during cardiac surgery has not been fully elucidated. Peak systolic tissue Doppler velocities of the lateral mitral annulus (S') have been used to evaluate LV systolic long-axis performance. We hypothesized that incremental sevoflurane concentration (1.0-3.0 inspired-vol%) would dose-dependently reduce S' in patients undergoing cardiac surgery due to mitral or aortic insufficiency. METHODS: In 20 patients undergoing cardiac surgery in sevoflurane-remifentanil anesthesia, we analyzed intraoperative S' values which were determined after 10 min exposure to sevoflurane at 1.0, 2.0, and 3.0 inspired-vol% (T1, T2, and T3, respectively) with a fixed remifentanil dose (1.0 µg/kg/min) using transesophageal echocardiography. RESULTS: Linear mixed-effect modeling demonstrated dose-dependent declines in S' according to the end-tidal sevoflurane concentration increments (C(ET)-sevoflurane, p < 0.001): the mean value of S' reduction for each 1.0 vol%-increment of C(ET)-sevoflurane was 1.7 cm/s (95 % confidence interval 1.4-2.1 cm/s). Medians of S' at T1, T2, and T3 (9.6, 8.9, and 7.5 cm/s, respectively) also exhibited significant declines (by 6.6, 15.6, and 21.2 % for T1 vs. T2, T2 vs. T3, and T1 vs. T3, p < 0.001, =0.002, and <0.001 in Friedman pairwise comparisons, respectively). CONCLUSIONS: Administering sevoflurane as a part of a sevoflurane-remifentanil anesthesia regimen appears to dose-dependently reduce S', indicating LV systolic performance, in patients undergoing cardiac surgery. Further studies may be required to evaluate the clinical implications of these findings.

The influence of positive end-expiratory pressure on stroke volume variation in patients undergoing cardiac surgery: an observational study.

OBJECTIVES: Measurements of stroke volume variation for volume management in mechanically ventilated patients are influenced by various factors, such as tidal volume, respiratory rate, and chest/lung compliance. However, research regarding the effect of positive end-expiratory pressure on stroke volume variation is limited. METHODS: Patients were divided into responder and nonresponder groups according to the prediction of fluid response by the passive leg raising test and hemodynamic parameters, including stroke volume variation, measured in all patients at the following ventilator settings: (1) conventional ventilation (C), tidal volume 10 mL · kg(-1) with positive end-expiratory pressure settings of 0 (C0), 5 (C5), and 10 cmH2O (C10) and (2) lung protective ventilation (P), tidal volume 6 mL · kg(-1) with positive end-expiratory pressure settings of 0 (P0), 5 (P5), and 10 cmH2O (P10). RESULTS: Regardless of ventilator setting, stroke volume variation in the responder group had an increasing trend as increased positive end-expiratory pressure level and was significantly higher than in the nonresponder group at each positive end-expiratory pressure level. The area under the curve was (1) 0.899 at C0, 0.942 at C5, and 0.985 at C10; and (2) 0.901 at P0, 0.932 at P5, and 0.947 at P10. Optimal threshold values given by receiver operating characteristic curve analysis were (1) 13.5%, 13.5%, and 14.5%; and (2) 13.5%, 13.5%, and 14.5%, respectively. CONCLUSIONS: The threshold value of stroke volume variation in predicting fluid responsiveness may change when positive end-expiratory pressure 10 cmH2O is applied. This must be considered when stroke volume variation is used to detect the fluid responsiveness to prevent volume overload in this mechanical ventilation setting.

The influence of different mechanical ventilator settings of peak inspiratory pressure on stroke volume variation in pediatric cardiac surgery patients.

BACKGROUND: The usefulness of dynamic parameters derived by heart-lung interaction for fluid responsiveness in pediatric patients has been revealed. However, the effects of peak inspiratory pressure (PIP) that could affect the absolute values and the accuracy in pediatric patients have not been well established. METHODS: Participants were 30 pediatric patients who underwent ventricular septal defect repair. After completion of surgical procedure and sternum closure, mean arterial blood pressure, heart rate, central venous pressure, cardiac output, cardiac index and stroke volume variation (SVV) were measured at PIP 10 cmH2O (PIP10), at PIP 15 cmH2O (PIP15), at PIP 20 cmH2O (PIP20) and at PIP 25 cmH2O (PIP25). RESULTS: SVV at PIP15 was larger than that at PIP10 (13.7 ± 2.9% at PIP10 vs 14.7 ± 2.5% at PIP15, P < 0.001) and SVV at PIP20 was larger than that at PIP10 and PIP15 (13.7 ± 2.9% at PIP10 vs 15.4 ± 2.5% at PIP20, P < 0.001; 14.7 ± 2.5% at PIP15 vs 15.4 ± 2.5% at PIP20, P < 0.001) and SVV at PIP25 was larger than that at PIP10 and PIP15 and PIP20 (13.7 ± 2.9% at PIP10 vs 17.4 ± 2.4% at PIP25, P < 0.001; 14.7 ± 2.5% at PIP15 vs 17.4 ± 2.4% at PIP25, P < 0.001; 15.4 ± 2.5% at PIP20 vs 17.4 ± 2.4% at PIP25, P < 0.001). CONCLUSIONS: SVV is affected by different levels of PIP in same patient and under same volume status. This finding must be taken into consideration when SVV is used to predict fluid responsiveness in mechanically ventilated pediatric patients.

Comparison of pulmonary gas exchange according to intraoperative ventilation modes for mitral valve repair surgery via thoracotomy with one-lung ventilation: a randomized controlled trial.

OBJECTIVE: Impaired pulmonary gas exchange after cardiac surgeries with cardiopulmonary bypass (CPB) often occurs, and the selection of mechanical ventilation mode, pressure-controlled ventilation (PCV) or volume-controlled ventilation (VCV), may be important for preventing hypoxia and improving oxygenation. The authors hypothesized that patients with PCV would show better oxygenation, compared with VCV, during one-lung ventilation (OLV) for mitral valve repair surgery (MVP) via thoracotomy. DESIGN: Randomized controlled trial. SETTING: University teaching hospital. PARTICIPANTS: Sixty patients in each group. INTERVENTIONS: MVP was performed using thoracotomy with OLV by PCV or VCV. MEASUREMENTS AND MAIN RESULTS: Arterial partial pressure of oxygen (PaO2) and fraction of inspired oxygen (FIO2) were measured before anesthesia induction (T0), at skin incision (T1), after administration of heparin (T2), at 30 minutes after CPB weaning (T3), just before departure from the operating room to the intensive care unit (ICU) (T4), and 1 hour after ICU admission (T5), and PaO2/FIO2 ratio was calculated. Peak inspiratory pressure (PIP) and mean inspiratory pressure (Pmean) were recorded at T1, T2, T3, and T4. No significant difference was noted in the PaO2/FIO2 ratio between the groups at any measured point. PIP in the PCV group at all measured points was lower than that in the VCV group (T1, p<0.001; T2, p<0.001; T3, p<0.001; T4, p=0.025, respectively). Pmean was not different between the two groups at any measured point. CONCLUSIONS: PCV during OLV in patients undergoing MVP via a thoracotomy with OLV showed lower PIP compared with VCV, but this did not improve pulmonary gas exchange.

Placing a saline bag underneath the heart enhances transgastric transesophageal echocardiographic imaging during cardiac displacement for off-pump coronary artery bypass surgery.

OBJECTIVE: The authors hypothesized that placing a saline bag (saline-filled surgical glove) underneath a displaced heart would improve ultrasound transmission for transgastric (TG) imaging and transesophageal echocardiography (TEE) to visualize left ventricular regional wall motion (LV-RWM) during cardiac displacement for off-pump coronary artery bypass (OPCAB) surgery. DESIGN: Prospective observational study. SETTING: Tertiary University Hospital. PARTICIPANTS: Adult patients undergoing OPCAB surgery. INTERVENTIONS: Intraoperative TEE examination MEASUREMENT AND MAIN RESULTS: For off-line analyses of LV-readable segments, mid-esophageal (ME, 4-chamber, 2-chamber, and long-axis) and TG (basal- and mid-short-axis) TEE views were recorded under 3 different intraoperative conditions in 13 cases of OPCAB surgery: Before cardiac displacement (Tcontrol), after cardiac displacement (Tdisplaced), and after placing the saline bag underneath the displaced heart (Tsaline-bag). There were more LV-readable segments in the 17-segment model using integrated ME and TG views(ME + TG views) at Tsaline-bag and Tcontrol (mean[95% confidence interval], 17[17-17] and 17[17-17]) than using ME+TG at Tdisplaced (15[15-16], P = 0.002 and P<0.001, respectively). Using ME + TG views provided more LV-readable segments in the 17-segment model than using ME views at Tsaline-bag (vs. 16[14-16], P < 0.001), but not at Tdisplaced (vs. 15[14-15]). Incidences of inadequate RWM monitoring (LV-readable segments<14/17 using ME + TG views) at Tsaline-bag and Tcontrol (all 0/13) were less frequent than at Tdisplaced (3/13, all P = 0.038). There were more LV-readable segments in TG basal- and mid-short-axis views at Tsaline-bag (median [range], 6[5-6] and 5[5-6]) than at Tdisplaced (0[0-2] and 0[0-1], all P < 0.05). CONCLUSIONS: Placing a saline bag underneath the displaced heart enhances the ability of TEE to visualize global LV-RWM by improving TG TEE imaging during OPCAB surgery.

Detection of left atrial thrombus in patients with mitral stenosis and atrial fibrillation: retrospective comparison of two-phase computed tomography, transoesophageal echocardiography and surgical findings.

OBJECTIVE: This retrospective study aims to assess the accuracy of two-phase computed tomography (CT) and transoesophageal echocardiography (TEE) for the detection of left atrial (LA) thrombus in patients with mitral stenosis (MS) and atrial fibrillation (AF), by using intraoperative findings as the reference standard. METHODS: Preoperative two-phase CT and intraoperative TEE were performed in 106 patients with MS and AF. The ratio (LAA/AAL) of Hounsfield units (HU) in the LA appendage (LAA) to the ascending aorta (AA) was calculated on the late-phase CT image. RESULTS: LA echodense masses on TEE and LA filling defects on two-phase CT were observed in 29 and 39 patients, respectively. Thirty-five LA thrombi were identified at surgery in 27 patients. Compared with the intraoperative findings, per-patient sensitivity, specificity, positive and negative predictive values of two-phase CT were 100 %, 85 %, 69 % and 100 %, and those by using TEE were 93 %, 95 %, 86 % and 97 % in detecting LAA thrombus. After adopting the cut-off value of 0.5 for the LAA/AAL HU ratio, the specificity and positive predictive value of two-phase CT were increased to 96 % and 90 %, respectively. CONCLUSION: Two-phase CT with a cut-off value of LAA/AAL HU ratio of 0.5 provides high performance for the detection of LAA thrombus. KEY POINTS: • Accurate detection of left atrial appendage (LAA) thrombus is extremely important. • However artefacts from flow effects influence both CT and ultrasound findings. • Two-phase ECG-gated CT offers new insight into thrombus detection. • Analysis of aortic/atrial opacification helps differentiate LAA thrombus from artefact at CT.