Effects of intraoperative inspired oxygen fraction (FiO2 0.3 vs 0.8) on patients undergoing off-pump coronary artery bypass grafting: the CARROT multicenter, cluster-randomized trial.

BACKGROUND: To maintain adequate oxygenation is of utmost importance in intraoperative care. However, clinical evidence supporting specific oxygen levels in distinct surgical settings is lacking. This study aimed to compare the effects of 30% and 80% oxygen in off-pump coronary artery bypass grafting (OPCAB). METHODS: This multicenter trial was conducted in three tertiary hospitals from August 2019 to August 2021. Patients undergoing OPCAB were cluster-randomized to receive either 30% or 80% oxygen intraoperatively, based on the month when the surgery was performed. The primary endpoint was the length of hospital stay. Intraoperative hemodynamic data were also compared. RESULTS: A total of 414 patients were cluster-randomized. Length of hospital stay was not different in the 30% oxygen group compared to the 80% oxygen group (median, 7.0 days vs 7.0 days; the sub-distribution hazard ratio, 0.98; 95% confidence interval [CI] 0.83-1.16; P = 0.808). The incidence of postoperative acute kidney injury was significantly higher in the 30% oxygen group than in the 80% oxygen group (30.7% vs 19.4%; odds ratio, 1.94; 95% CI 1.18-3.17; P = 0.036). Intraoperative time-weighted average mixed venous oxygen saturation was significantly higher in the 80% oxygen group (74% vs 64%; P < 0.001). The 80% oxygen group also had a significantly greater intraoperative time-weighted average cerebral regional oxygen saturation than the 30% oxygen group (56% vs 52%; P = 0.002). CONCLUSIONS: In patients undergoing OPCAB, intraoperative administration of 80% oxygen did not decrease the length of hospital stay, compared to 30% oxygen, but may reduce postoperative acute kidney injury. Moreover, compared to 30% oxygen, intraoperative use of 80% oxygen improved oxygen delivery in patients undergoing OPCAB. Trial registration ClinicalTrials.gov (NCT03945565; April 8, 2019).

Evaluation of Different Near-Infrared Spectroscopy Devices for Assessing Tissue Oxygenation with a Vascular Occlusion Test in Healthy Volunteers.

Near-infrared spectroscopy devices can measure peripheral tissue oxygen saturation (StO2). This study aims to compare StO2 using INVOS® and different O3™ settings (O325:75 and O330:70). Twenty adults were recruited. INVOS® and O3™ probes were placed simultaneously on 1 side of forearm. After baseline measurement, the vascular occlusion test was initiated. The baseline value, rate of deoxygenation and reoxygenation, minimum and peak StO2, and time from cuff release to peak value were measured. The parameters were compared using ANOVA and Kruskal-Wallis tests. Bonferroni's correction and Mann-Whitney pairwise comparison were used for post hoc analysis. The agreement between StO2 of devices was evaluated using Bland-Altman plots. INVOS® baseline value was higher (79.7 ± 6.4%) than that of O325:75 and O330:70 (62.4 ± 6.0% and 63.7 ± 5.5%, respectively, p < 0.001). The deoxygenation rate was higher with INVOS® (10.6 ± 2.1%/min) than with O325:75 and O330:70 (8.4 ± 2.2%/min, p = 0.006 and 7.5 ± 2.1%/min, p < 0.001). The minimum and peak StO2 were higher with INVOS®. No significant difference in the reoxygenation rate was found between the devices and settings. The time to reach peak after cuff deflation was faster with INVOS® (both p < 0.001). Other parameters were similar. There were no differences between the different O3™ settings. There were differences in StO2 measurements between the devices, and these devices should not be interchanged. Differences were not observed between O3™ device settings.

Neutrophil/Lymphocyte Ratio in Patients Undergoing Noncardiac Surgery After Coronary Stent Implantation.

OBJECTIVE: Perioperative cell count-associated predictors, including the neutrophil/lymphocyte ratio (N/LR) and platelet/lymphocyte ratio (P/LR), are associated with poor clinical outcomes including myocardial injury. Study investigators aimed to examine the association among the perioperative N/LR, P/LR, and postoperative major adverse cardiovascular and cerebral events (MACCE) after noncardiac surgery in patients with drug-eluting stent (DES) insertion. DESIGN: Retrospective and observational. SETTING: Single university hospital. PARTICIPANTS: The study comprised 965 patients who underwent noncardiac surgery within 6 months after DES implantation. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Baseline perioperative clinical parameters, including N/LR and P/LR measured before surgery, immediately after surgery, and on postoperative day (POD) 1, were obtained. MACCE was defined as a composite of nonfatal myocardial infarction, coronary revascularization, nonhemorrhagic stroke, and pulmonary embolism within 1 month after surgery. Multivariate logistic regression analysis and propensity score matching were used to identify predictors of MACCE after surgery. MACCE occurred in 67 patients (6.9%) and was more common in patients with N/LR on POD 1 >4.3 (multivariable-adjusted odds ratio [OR] 2.03, 95% confidence interval [CI] 1.12-2.79; p = 0.040 and as a continuous N/LR [OR 1.17, 95% CI 1.08-1.27; p < 0.001]). This association was consistent after propensity score matching and was stronger when the antiplatelet agent was stopped before surgery (OR 3.02, 95% CI 2.14-4.48; p = 0.006 for stopping dual antiplatelet therapy). CONCLUSIONS: In patients undergoing noncardiac surgery within 6 months after DES implantation, elevated N/LR on POD 1 is independently associated with postoperative MACCE. Elevated postoperative N/LR as a marker of systemic inflammation may help to predict the development of MACCE in these high-risk patients.

Flow-Mediated Dilatation of the Brachial Artery for Assessing Endothelial Dysfunction in Children with Moyamoya Disease.

BACKGROUND: Moyamoya disease is a progressive, steno-occlusive arteriopathy involving the internal carotid artery and its branches and causing recurrent stroke episodes in children. Patients with moyamoya disease may be more susceptible to influences that cause endothelial dysfunction. We evaluated whether flow-mediated dilatation (FMD) of the brachial artery is useful for assessing endothelial dysfunction in children with moyamoya disease. METHODS: This prospective observational study included 30 children with moyamoya disease and 30 controls. After anesthesia induction, a blood pressure cuff was applied to the forearm and inflated to a pressure that was 50 mm Hg above the baseline systolic blood pressure for 5 min. From 30 s before to 2 min after deflation, the brachial artery diameter was recorded on ultrasound. The increase in internal diameter was expressed as the percentage of the baseline diameter. RESULTS: Fifty-nine patients were analyzed. Baseline brachial artery diameters in the moyamoya and control groups were 3.00 and 3.37 mm, respectively (p = 0.004; difference, 0.38; 95% CI 0.12-0.63), while those after deflation were 3.06 and 3.48 mm, respectively (p = 0.003; difference, 0.42; 95% CI 0.15-0.68). The percent change of the baseline diameter value was 4.0% in the disease group and 8.3% in the control group (p = 0.10). There was a group and time interaction for brachial artery diameter (p = 0.01; main effect of group, p = 0.009; main effect of time, p = 0.007). CONCLUSION: FMD of the brachial artery may not be enough for determining endothelial dysfunction under general anesthesia in children with moyamoya disease.

The Hemodynamic Effect of Epinephrine-Containing Local Infiltration Analgesia After Tourniquet Deflation During Total Knee Arthroplasty: A Retrospective Observational Study.

BACKGROUND: Local infiltration analgesia (LIA) is widely used in patients undergoing total knee arthroplasty and often contains epinephrine for a prolonged analgesic effect and to reduce systemic absorption of the local anesthetic. This retrospective observational study investigated the hemodynamic effect of locally infiltrated epinephrine after deflation of the tourniquet during total knee arthroplasty. METHODS: We reviewed the electronic medical records of patients who underwent total knee arthroplasty between January 2017 and February 2018 at a tertiary care university hospital. Total knee arthroplasty was performed using a conventional technique with a pneumatic tourniquet. LIA consisted of ropivacaine, morphine sulfate, ketorolac, and methylprednisolone. The patients were grouped according to whether or not epinephrine was included in the LIA. The incidence of a hypertensive response (systolic blood pressure >160 mmHg or mean blood pressure >110 mmHg) after deflation of the tourniquet was compared between the 2 groups. RESULTS: A total of 452 patients had received LIA with (n = 188) or without (n = 264) epinephrine. A hypertensive response after deflation of the tourniquet was more common in patients who received LIA containing epinephrine (42/188 [22.3%]) than in those who received LIA without epinephrine (14/264 [5.3%], P < .001). However, the incidence of hypotension after deflation of the tourniquet was not significantly different between the 2 groups (P = .976). CONCLUSION: Because epinephrine-containing LIA can result in a hypertensive response after deflation of the tourniquet during total knee arthroplasty, it should be cautiously administered, especially in patients with cardiovascular comorbidities.

Cervical Spine Motion During Tracheal Intubation Using an Optiscope Versus the McGrath Videolaryngoscope in Patients With Simulated Cervical Immobilization: A Prospective Randomized Crossover Study.

BACKGROUND: In patients with an unstable cervical spine, maintenance of cervical immobilization during tracheal intubation is important. In McGrath videolaryngoscopic intubation, lifting of the blade to raise the epiglottis is needed to visualize the glottis, but in patients with an unstable cervical spine, this can cause cervical spine movement. By contrast, the Optiscope, a rigid video-stylet, does not require raising of the epiglottis during tracheal intubation. We therefore hypothesized that the Optiscope would produce less cervical spine movement than the McGrath videolaryngoscope during tracheal intubation. The aim of this study was to compare the Optiscope with the McGrath videolaryngoscope with respect to cervical spine motion during intubation in patients with simulated cervical immobilization. METHODS: The primary outcome of the study was the extent of cervical spine motion at the occiput-C1, C1-C2, and C2-C5 segments. In this randomized crossover study, the cervical spine angle was measured before and during tracheal intubation using either the Optiscope or the McGrath videolaryngoscope in 21 patients with simulated cervical immobilization. Cervical spine motion was defined as the change in angle at each cervical segment during tracheal intubation. RESULTS: There was significantly less cervical spine motion at the occiput-C1 segment using the Optiscope rather than the McGrath videolaryngoscope (mean [98.33% CI]: 4.7° [2.4-7.0] vs 10.4° [8.1-12.7]; mean difference [98.33% CI]: -5.7° [-7.5 to -3.9]). There were also fewer cervical spinal motions at the C1-C2 and C2-C5 segments using the Optiscope (mean difference versus the McGrath videolaryngoscope [98.33% CI]: -2.4° [-3.7 to -1.2]) and -3.7° [-5.9 to -1.4], respectively). CONCLUSIONS: The Optiscope produces less cervical spine motion than the McGrath videolaryngoscope during tracheal intubation of patients with simulated cervical immobilization.

The Effect of Remote Ischemic Preconditioning on Serum Creatinine in Patients Undergoing Partial Nephrectomy: A Randomized Controlled Trial.

Renal function declines after partial nephrectomy due to ischemic reperfusion injury induced by surgical insult or renal artery clamping. The effect of remote ischemic preconditioning (RIPC) on reducing renal injury after partial nephrectomy has not been studied regarding urinary biomarkers. Eighty-one patients undergoing partial nephrectomy were randomly assigned to either RIPC or the control group. RIPC protocol consisted of four cycles of five-min inflation and deflation of a blood pressure cuff to 250 mmHg. Serum creatinine levels were compared at the following time points: preoperative baseline, immediate postoperative, on the first and third days after surgery, and two weeks after surgery. The incidence of acute kidney injury, other surgical complication rates, and urinary biomarkers, including urine creatinine, ß-2 microglobulin, microalbumin, and N-acetyl-beta-D-glucosaminidase were compared. Split renal functions measured by renal scan were compared up to 18 months after surgery. There was no significant difference in the serum creatinine level on the first postoperative day (median (interquartile range) 0.87 mg/dL (0.72-1.03) in the RIPC group vs. 0.92 mg/dL (0.71-1.12) in the control group, p = 0.728), nor at any other time point. There was no significant difference in the incidence of acute kidney injury. Secondary outcomes, including urinary biomarkers, were not significantly different between the groups. RIPC showed no significant effect on the postoperative serum creatinine level of the first postoperative day. We could not reveal any significant difference in the urinary biomarkers and clinical outcomes. However, further larger randomized trials are required, because our study was not sufficiently powered for the secondary outcomes.

Continuous Non-Invasive Arterial Pressure Monitoring (ClearSight System) and Ankle Blood Pressure Measurements as Alternatives to Conventional Arm Blood Pressure.

Measuring blood pressure (BP) via a pneumatic cuff placed around the arm has long been the standard method. However, in clinical situations where BP monitoring at the arm is difficult, the ankle is frequently used instead. We compared continuous non-invasive blood pressure (CNBP) measurements obtained at the finger, ankle BP and arm BP in patients undergoing breast cancer surgery. Arm BP, ankle BP (both obtained with a conventional pneumatic cuff) and CNBP measurements were obtained every 2.5 min during surgery. Correlation and Bland-Altman analyses were performed and differences among measurements were analyzed using a linear mixed model. A total of 245 sets of BP measurements were obtained from 10 patients. All systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean blood pressure (MBP) measurements of ankle BP and CNBP were positively correlated with the arm BP measurements (Spearman rho 0.688-0.836, p < 0.001 for each correlation). The difference between CNBP and arm SBP was significantly smaller (least squares mean (95% confidence interval): -6.03 (-11.40, -0.67)) compared to that between ankle and arm SBP (least squares mean (95% CI): -15.32 (-20.69, -9.96), p = 0.019). However, this significant difference was not observed in DBP and MBP (-1.23 vs. 1.75, p = 0.190 and -3.85 vs. -2.63, p = 0.604, respectively). Ankle SBP measurements showed larger differences from arm SBP measurements than did CNBP SBP measurements in patients undergoing breast cancer surgery. CNBP could serve as a useful alternative to ankle BP when standard arm BP measurements cannot be obtained.

Predictive Factors for Hypotension Associated With Supine-to-Prone Positional Change in Patients Undergoing Spine Surgery.

BACKGROUND: Positional change during general anesthesia can cause hypotension. The objective of this retrospective study was to determine predictive factors for hypotension associated with supine-to-prone positional change in spinal surgery patients. MATERIALS AND METHODS: Data on demographics, current medications, comorbidity, intraoperative mean arterial pressure (MAP), heart rate, pulse pressure variation, tidal volume, peak inspiratory pressure, and propofol and remifentanil effect-site concentrations were collected from 179 patients undergoing elective spine surgery. Hypotension associated with supine-to-prone positional change was defined as >20% reduction in MAP during positional change. RESULTS: Hypotension associated with supine-to-prone positional change was observed in 16 (8.9%) patients. The median (interquartile range) effect-site concentration of remifentanil (5.3 [4.0 to 8.5] vs. 4.0 [3.1 to 4.0] ng/mL, P<0.001), MAP (95.0 [86.0 to 103.5] vs. 80.0 [70.0 to 94.0] mm Hg, P=0.014), peak inspiratory pressure (16.5 [15.0 to 18.5] vs. 15.0 [14.0 to 17.0] hPa, P=0.040) in the supine position, and pulse pressure variation in the prone position (12.0 [9.0 to 16.4] vs. 9.0 [7.0 to 12.0]%, P=0.019) were significantly higher in the hypotension group. In multivariate logistic regression analysis, the effect-site concentration of remifentanil (odd ratio [95% confidence interval], 2.12 [1.51-2.96], P<0.001), preoperative use of beta-blocker (7.64 [1.21-48.36], P=0.031), and MAP in the supine position (1.04 [1.00-1.07], P=0.033) were independent predictive factors for hypotension associated with supine-to-prone positional change. CONCLUSIONS: Increased effect-site concentration of remifentanil, preoperative use of beta-blocker, and high MAP in the supine position were predictive factors for hypotension associated with supine-to-prone positional change in spinal surgery patients.

Effect of Perioperative Low-Dose Dexmedetomidine on Postoperative Delirium After Living-Donor Liver Transplantation: A Randomized Controlled Trial.

BACKGROUND: Postoperative delirium after liver transplantation (LT) is associated with increased hospital length of stay and higher morbidity and mortality. Dexmedetomidine is a recommended and widely used sedative in critically ill patients with reports of potential for delirium prevention. METHODS: A randomized controlled clinical trial was performed to investigate whether perioperative low-dose dexmedetomidine infusion would decrease delirium after living-donor LT. Dexmedetomidine (0.1 mcg/kg/hour) was administered during anesthesia and through postoperative day 2 for patients in the dexmedetomidine group, whereas 0.9% saline was administered at the same rate for the same duration for patients in the control group. The incidence of delirium after LT was compared between the 2 groups. Delirium duration, mechanical ventilation duration, intensive care unit (ICU) and hospital length of stay, and in-hospital and 3-month mortality were also compared. RESULTS: There was no significant difference in delirium incidence in the dexmedetomidine group compared to the control group (9% vs 5.9%; P = .44). Duration of delirium and mechanical ventilation, ICU and hospital length of stay, and in-hospital and 3-month mortality were comparable between the 2 groups. CONCLUSIONS: Perioperative low-dose dexmedetomidine infusion did not reduce the incidence of delirium in living-donor LT.

Virtual Reality Distraction during Endoscopic Urologic Surgery under Spinal Anesthesia: A Randomized Controlled Trial.

Sedation protocols during spinal anesthesia often involve sedative drugs associated with complications. We investigated whether virtual reality (VR) distraction could be applied during endoscopic urologic surgery under spinal anesthesia and yield better satisfaction than pharmacologic sedation. VR distraction without sedative was compared with pharmacologic sedation using repeat doses of midazolam 1⁻2 mg every 30 min during urologic surgery under spinal anesthesia. We compared the satisfaction of patients, surgeons, and anesthesiologists, as rated on a 5-point prespecified verbal rating scale. Two surgeons and two anesthesiologists rated the scale and an overall score was reported after discussion. Thirty-seven patients were randomized to a VR group (n = 18) or a sedation group (n = 19). The anesthesiologist's satisfaction score was significantly higher in the VR group than in the sedation group (median (interquartile range) 5 (5⁻5) vs. 4 (4⁻5), p = 0.005). The likelihood of both patients and anesthesiologists being extremely satisfied was significantly higher in the VR group than in the sedation group. Agreement between the scores for surgeons and those for anesthesiologists was very good (kappa = 0.874 and 0.944, respectively). The incidence of apnea was significantly lower in the VR group than in the sedation group (n = 1, 5.6% vs. n = 7, 36.8%, p = 0.042). The present findings suggest that VR distraction is better than drug sedation with midazolam in terms of patient's and anesthesiologist's satisfaction and avoiding the respiratory side effects of midazolam during endoscopic urologic surgery under spinal anesthesia.

Successful laparoscopic surgery for 14-month-old infant with ovarian torsion.

The prevalence of ovarian torsion is 4.9 among 100,000 females between ages 1 to 20 years. The diagnosis of ovarian torsion in children, especially in infants, is very difficult. Since they cannot explain related symptoms accurately, and reproductive organs lie high in the abdomen, physical examination shows unclear findings. For these reasons, we use imaging studies, such as ultrasonography and magnetic resonance imaging, to diagnose ovarian torsion. However, it is of limited value to diagnose by using these modalities alone. Therefore, clinical suspicion is important for diagnosis. Though pediatric laparoscopic surgery was introduced 20 years ago, it has been widely performed since the mid 1990s with the development of 3-mm instruments. In addition, usually the pediatric operation is done in the pediatric surgery office, even though it is a gynecologic procedure. In addition, laparotomy is still more frequently conducted in current clinical practice, although the frequency of laparoscopic surgery has increased. However, it is thought that expert gynecologic surgeons can perform pediatric laparoscopic operations if they pay attention to some precautions. We report herein the case of a 14-month-old infant who underwent emergency laparoscopic untwisting of ovarian torsion successfully without complications by a gynecologic surgeon, with a brief review of the literature.

Concept of minimal heart rate for each pitch value to avoid interpolation artifact when using dual-source CT: a phantom study.

Interpolation artifact is known to occur when the heart rate is decreased lower than the critical value for the specific pitch. The purpose of our study is to determine the minimum heart rate (minHR) for the specific pitch that provides images without interpolation artifact when using dual-source computed tomography (DSCT). We scanned the 'thin slice thickness block' of the CT performance phantom provided by the American Association of Physicists in Medicine using DSCT for variable pitches. Change in heart rate was simulated through ECG editing by changing R-R interval. Axial, sagittal, and coronal image sets were reconstructed and assessed for the presence and extent of interpolation artifact. MinHR at which no interpolation artifact was detected for each pitch value was determined. Length of interpolation artifact (LOA) on sagittal view was also measured when the heart rate was simulated at 10 bpm lower than the minHR on each pitch setting. MinHRs for each pitch value were 9-10 bpm from the estimated heart rate. However, minHR for the lowest pitch value 0.2, estimated heart value 40 bpm was 37 bpm. LOA was larger in the low heart rate condition. Measured values of minHR were correlated exactly with the calculated values. MinHRs that provide images without interpolation artifact for each pitch value when using DSCT were determined. The concept of minHR is important for obtaining high quality images of cardiac CT angiography when using DSCT.