Impact of intraoperative fluid management on postoperative complications in patients undergoing minimally invasive esophagectomy for esophageal cancer: a retrospective single-center study.

BACKGROUND: Esophagectomy is a high-risk procedure that can involve serious postoperative complications. There has been an increase in the number of minimally invasive esophagectomies (MIEs) being performed. However, the relationship between intraoperative management and postoperative complications in MIE remains unclear. METHODS: After the institutional review board approval, we enrolled 300 patients who underwent MIE at Tohoku University Hospital between April 2016 and March 2021. The relationships among patient characteristics, intraoperative and perioperative factors, and postoperative complications were retrospectively analyzed. The primary outcome was the relationship between intraoperative fluid volume and anastomotic leakage, and the secondary outcomes included the associations between other perioperative factors and postoperative complications. RESULTS: Among 300 patients, 28 were excluded because of missing data; accordingly, 272 patients were included in the final analysis. The median [interquartile range] operative duration was 599 [545-682] minutes; total intraoperative infusion volume was 3,747 [3,038-4,399] mL; total infusion volume per body weight per hour was 5.48 [4.42-6.73] mL/kg/h; and fluid balance was + 2,648 [2,015-3,263] mL. The postoperative complications included anastomotic leakage in 68 (25%) patients, recurrent nerve palsy in 91 (33%) patients, pneumonia in 62 (23%) patients, cardiac arrhythmia in 13 (5%) patients, acute kidney injury in 5 (2%) patients, and heart failure in 5 (2%) patients. The Cochrane-Armitage trend test indicated significantly increased anastomotic leakage among patients with a relatively high total infusion volume (P = 0.0085). Moreover, anastomotic leakage was associated with male sex but not with peak serum lactate levels. Patients with a longer anesthesia duration or recurrent nerve palsy had a significantly higher incidence of postoperative pneumonia than those without. Further, the incidence of postoperative pneumonia was not associated with the operative duration, total infusion volume, or fluid balance. The operative duration and blood loss were related to the total infusion volume. Acute kidney injury was not associated with the total infusion volume or serum lactate levels. CONCLUSIONS: Among patients who underwent MIE, the total infusion volume was positively correlated with the incidence of anastomotic leakage. Further, postoperative pneumonia was associated with recurrent nerve palsy but not total infusion volume or fluid balance.

Aortic valve replacement in a 41-year-old woman with uncorrected tetralogy of Fallot, pulmonary atresia, and major aortopulmonary collateral arteries: a case report.

BACKGROUND: Tetralogy of Fallot (TOF) is a complex cyanotic congenital heart disease. As most patients with TOF undergo palliative or radical surgical repair during childhood, cardiac surgery under cardiopulmonary bypass (CPB) for adult survivors with unrepaired TOF is exceedingly rare. CASE PRESENTATION: A 41-year-old woman with unrepaired TOF, pulmonary atresia (PA), and major aortopulmonary collateral arteries (MAPCAs) developed acute infectious endocarditis (IE). As vegetation gradually increased despite intravenous antibiotic administration, she was scheduled for urgent aortic valve replacement under CPB. Pulmonary blood flow was primarily provided by the MAPCAs originating from the descending aorta. Intra-aortic balloon occlusion for MAPCAs was performed to ensure a bloodless surgical field. Aortic valve replacement was successful. CONCLUSION: An adult with uncorrected TOF developed acute IE and subsequently had successful cardiac surgery under CPB. Understanding TOF physiology with PA and MAPCAs, particularly pulmonary blood flow through MAPCAs, is crucial.

Transvenous Radiofrequency Catheter Ablation for an Aldosterone-Producing Tumor of the Left Adrenal Gland: A First in Human Case Report.

PURPOSE: To describe a novel technique of transvenous radiofrequency catheter ablation of an aldosterone-producing adenoma (APA) of the left adrenal gland using the GOS System (Japan Lifeline, Tokyo, Japan). Using the GOS system, a flexible radiofrequency tip catheter can be inserted into the adrenal central and tributary veins, the drainers for functional tumors. MATERIALS AND METHODS: An APA at the left adrenal gland, which was diagnosed by segmental adrenal venous sampling following administration of 0.25 mg cosyntropin, was ablated using the GOS catheter inserted into adrenal tributary veins via a right femoral vein 7-Fr sheath. The effect of radiofrequency ablation on APA was assessed using the international consensus on surgical outcomes for unilateral primary aldosteronism (PA). RESULTS: No device-related complications were observed. The patient was deeply sedated under blood pressure and heart rate control with continuous administration of ß-blockers. Then, the tumor and surrounding adrenal gland were cauterized at 7000 J two times each in sequence. The output time was 7-11 min for each ablation and 80 min in total. For blood pressure and pulse rate control, esmolol hydrochloride and phentolamine mesylate were used. The contrast enhancement of APA disappeared on dynamic CT immediately after the procedure. PA was biochemically cured until 12 months after the procedure. CONCLUSION: Using the radiofrequency device with the GOS catheter and system is a method for cauterizing adrenal tumors from blood vessels. This approach resulted in a marked reduction in aldosterone concentrations and a complete biochemical cure of PA over the observation period.

Endotracheal tube, by the venturi effect, reduces the efficacy of increasing inlet pressure in improving pendelluft.

In mechanically ventilated severe acute respiratory distress syndrome patients, spontaneous inspiratory effort generates more negative pressure in the dorsal lung than in the ventral lung. The airflow caused by this pressure difference is called pendelluft, which is a possible mechanisms of patient self-inflicted lung injury. This study aimed to use computer simulation to understand how the endotracheal tube and insufficient ventilatory support contribute to pendelluft. We established two models. In the invasive model, an endotracheal tube was connected to the tracheobronchial tree with 34 outlets grouped into six locations: the right and left upper, lower, and middle lobes. In the non-invasive model, the upper airway, including the glottis, was connected to the tracheobronchial tree. To recreate the inspiratory effort of acute respiratory distress syndrome patients, the lower lobe pressure was set at -13 cmH2O, while the upper and middle lobe pressure was set at -6.4 cmH2O. The inlet pressure was set from 10 to 30 cmH2O to recreate ventilatory support. Using the finite volume method, the total flow rates through each model and toward each lobe were calculated. The invasive model had half the total flow rate of the non-invasive model (1.92 L/s versus 3.73 L/s under 10 cmH2O, respectively). More pendelluft (gas flow into the model from the outlets) was observed in the invasive model than in the non-invasive model. The inlet pressure increase from 10 to 30 cmH2O decreased pendelluft by 11% and 29% in the invasive and non-invasive models, respectively. In the invasive model, a faster jet flowed from the tip of the endotracheal tube toward the lower lobes, consequently entraining gas from the upper and middle lobes. Increasing ventilatory support intensifies the jet from the endotracheal tube, causing a venturi effect at the bifurcation in the tracheobronchial tree. Clinically acceptable ventilatory support cannot completely prevent pendelluft.

Bilateral lung transplant with pulmonary artery reconstruction using donor aorta for pulmonary hypertension with a giant pulmonary arterial aneurysm.

OBJECTIVES: Standard bilateral lung transplantation (BLT) is not feasible for patients with pulmonary arterial hypertension (PAH) complicated with a giant pulmonary arterial aneurysm (PAA). This study aimed to describe the outcomes of BLT with pulmonary artery reconstruction (PAR) using donor aorta for such patients. METHODS: This is a retrospective single-centre study reviewing PAH patients with a PAA who received BLT with PAR using donor aorta from January 2010 through December 2020. We compared the characteristics and short- and long-term outcomes of recipients receiving PAR (PAR group) with those who had no PAA and received standard BLT (non-PAR group). RESULTS: Nineteen adult PAH patients underwent cadaveric lung transplantation during the study period. Among them, 5 patients with a giant PAA (median pulmonary artery trunk diameter, 69.9 mm) underwent BLT with PAR using donor aorta and the others received standard BLT. Although the operation time tended to be longer in the PAR group compared with the non-PAR group (1239 vs 958 mins, P = 0.087), 90-day mortality (PAR group: 0% vs non-PAR group: 14.3%, P > 0.99), and 5-year survival rate (PAR group: 100% vs non-PAR group: 85.7%, P = 0.74) was comparable between the groups. No dilatation, constriction or infection of the aortic grafts were recorded during the study period with a median follow-up time of 94 months in the PAR group. CONCLUSIONS: Lung transplantation with PAR using donor aorta is a valid surgical option for PAH patients complicated with a giant PAA.

Effectiveness of substantial shortening of the endotracheal tube for decreasing airway resistance and increasing tidal volume during pressure-controlled ventilation in pediatric patients: a prospective observational study.

The endotracheal tubes (ETTs) used for children have a smaller inner diameter. Accordingly, the resistance across ETT (RETT) is higher. Theoretically, shortening the ETTs can decrease total airway resistance (Rtotal), because Rtotal is sum of RETT and patient's airway resistance. However, the effectiveness of ETT shortening for mechanical ventilation in the clinical setting has not been reported. We assessed the effectiveness of shortening a cuffed ETT for decreasing Rtotal, and increasing tidal volume (TV), and estimated the RETT/Rtotal ratio in children. In anesthetized children in a constant pressure-controlled ventilation setting, Rtotal and TV were measured with a pneumotachometer before and after shortening a cuffed ETT. In a laboratory experiment, the pressure gradient across the original length, shortened length, and the slip joint alone of the ETT were measured. We then determined the RETT/Rtotal ratio using the above results. The clinical study included 22 children. The median ETT percent shortening was 21.7%. Median Rtotal was decreased from 26 to 24 cmH2O/L/s, and median TV was increased by 6% after ETT shortening. The laboratory experiment showed that ETT length and the pressure gradient across ETT are linearly related under a certain flow rate, and approximately 40% of the pressure gradient across the ETT at its original length was generated by the slip joint. Median RETT/Rtotal ratio were calculated as 0.69. The effectiveness of ETT shortening on Rtotal and TV was very limited, because the resistance of the slip joint was very large.

Accuracy of Cardiac Output Measured by Fourth-Generation FloTrac and LiDCOrapid, and Their Characteristics Regarding Systemic Vascular Resistance in Patients Undergoing Cardiac Surgery.

OBJECTIVES: The clinical use of less-invasive devices that calculate the cardiac output from arterial pressure waveform is increasing. The authors aimed to evaluate the accuracy and characteristics of the systemic vascular resistance index (SVRI) of the cardiac index measured by 2 less-invasive devices, fourth-generation FloTrac (CIFT) and LiDCOrapid (CILR), compared with the intermittent thermodilution technique, using a pulmonary artery catheter (CITD). DESIGN: This was a prospective observational study. SETTING: This study was conducted at a single university hospital. PARTICIPANTS: Twenty-nine adult patients undergoing elective cardiac surgery. INTERVENTIONS: Elective cardiac surgery was used as an intervention. MEASUREMENTS AND MAIN RESULTS: Hemodynamic parameters, CIFT, CILR, and CITD, were measured after the induction of general anesthesia, at the start of cardiopulmonary bypass, after completion of weaning from cardiopulmonary bypass, 30 minutes after weaning, and at sternal closure (135 measurements in total). The CIFT and CILR had moderate correlations with CITD (r = 0.62 and 0.58, respectively). Compared with CITD, CIFT, and CILR had a bias of -0.73 and -0.61 L/min/m2, limit of agreement of -2.14-to-0.68 L/min/m2 and -2.42-to-1.20 L/min/m2, and percentage error of 39.9% and 51.2%, respectively. Subgroup analysis for evaluating SVRI characteristics showed that the percentage errors of CIFT and CILR were 33.9% and 54.5% in low SVRI (<1,200 dyne×s/cm5/m), 37.6% and 47.9% in moderate SVRI (1,200-1,800 dyne×s/cm5/m), 49.3% and 50.6% in high SVRI (>1,800 dyne·s/cm5/m2), respectively. CONCLUSIONS: The accuracy of CIFT or CILR was not clinically acceptable for cardiac surgery. Fourth-generation FloTrac was unreliable in high SVRI. LiDCOrapid was inaccurate across a broad range of SVRI, and minimally affected by SVRI.

Postreperfusion Syndrome Presenting as Posttransplant Portal Hypertension due to Prolonged Elevation of Pulmonary Vascular Resistance and the Role of Nitroglycerin in Diagnosis and Treatment: A Case Report of Budd-Chiari Syndrome.

Postreperfusion syndrome is one of the responsible mechanisms of portal hypertension in patients undergoing liver transplantation. And post-transplant portal hypertension causes graft dysfunction. Postreperfusion syndrome is characterized by a decrease in arterial pressure and cardiac output, and an increase in central venous pressure, pulmonary artery pressure, and pulmonary vascular resistance that occurs after the release of the portal vein clamp. Although early recovery from postreperfusion syndrome is desired, there is a little medication therapy such as the administration of calcium chloride, sodium bicarbonate, and beta-agonist for postreperfusion syndrome. We present a case of postreperfusion syndrome manifested as post-transplant portal hypertension and reversed after nitroglycerin administration. A 49-year-old Asian woman was scheduled for liver transplantation because of Budd-Chiari syndrome. After portal vein reperfusion, she experienced severe postreperfusion syndrome. Administration of ephedrine and calcium restored arterial pressure; however, pulmonary artery pressure, pulmonary vascular resistance, and central venous pressure elevations were sustained, causing right ventricular overload. This condition did not improve after hepatic artery reperfusion, and caused post-transplant portal hypertension. After nitroglycerin administration, pulmonary vascular resistance and central venous pressure decreased, mean arterial pressure increased, right heart contractility recovered, and portal hypertension disappeared. Hemodynamic improvement by nitroglycerin administration helped in diagnosing postreperfusion syndrome and avoiding unnecessary splenectomy. If portal vein pressure increases after liver transplantation, the change in hemodynamic parameters by nitroglycerin administration should be assessed, which will lead to accurate diagnosis and appropriate treatment. Furthermore, postreperfusion syndrome should be listed as a differential diagnosis of post-transplant portal hypertension.

Worsening Right Ventricular Function during Cardiac Surgery Is a Strong Predictor of Postoperative Acute Kidney Injury: A Prospective Observational Study.

This prospective, observational study was conducted in a university hospital to verify that intraoperative worsening of right ventricular function causes cardiac surgery-associated acute kidney injury. Adult patients undergoing cardiac surgery under mid-sternal incision with cardiopulmonary bypass were included. Echocardiographic right and left ventricular function parameters were measured before and after bypass and compared using the Wilcoxon signed-rank test. Perioperative serum creatinine values at baseline and within the first 48 hours postoperatively were measured for the diagnosis of acute kidney injury. Spearman rank-order correlation (ρ) and receiver operating characteristic analysis were used to reveal relationships. Thirty-four patients were evaluated. Right ventricular ejection fraction (56.2 ± 7.0 vs. 51.6 ± 7.2%; P = 0.0002), right ventricular fractional area change (49.1 ± 6.4 vs. 46.6 ± 5.3%; P = 0.0201; mean ± standard deviation), and left ventricular ejection fraction (57.4 ± 6.1 vs. 51.7 ± 6.2%; P < 0.0001) were significantly decreased. Central venous pressure was significantly increased (7.2 ± 3.5 vs. 9.7 ± 3.7; P = 0.0001). Serum creatinine values increased from 0.82 [0.70-1.08] to 0.99 [0.82-1.54] mg/dL (P < 0.0001; median [interquartile range]). Changes in right ventricular ejection fraction, fractional area change, and right ventricular strain during cardiovascular surgery were significantly correlated with changes in serum creatinine values. Fractional area change exhibited the strongest correlation (ρ = -0.61, P < 0.0001). Change in fractional area change showed an area under the curve of 0.902 and a cutoff value of -2.1, which predicted acute kidney injury with 92% sensitivity, 73% specificity, and 79% accuracy. The functions of both ventricles were decreased after cardiopulmonary bypass. Worsening right ventricular function was independently correlated with postoperative renal dysfunction, and fractional area change was the strongest predictor of cardiac surgery-associated acute kidney injury.

Changes in haemodynamics during single lung transplantation under venovenous extracorporeal membrane oxygenation.

OBJECTIVES: The objective of the present study was to examine the effect of venovenous (VV) extracorporeal membrane oxygenation (ECMO) use on the haemodynamics during single lung transplantation (SLT) and postoperative course. METHODS: Forty-seven patients who underwent SLT for end-stage lung diseases in our lung transplant centre between January 2010 and December 2019 were included in this study. The recipients were divided into 3 groups according to the type of intraoperative ECMO. No type of ECMO was intra-operatively used in the patients of the no use of ECMO (NO ECMO) group. The patients in the venoarterial (VA) and VV ECMO groups were put on VA and VV ECMO during the surgery, respectively. The data were compared among the 3 groups. RESULTS: There were 13 SLT cases in the NO ECMO group, 23 SLT cases in the VA ECMO group and 11 SLT cases in the VV ECMO group. Re-exploration for bleeding was performed in 3 (13.0%) recipients in the VA ECMO group. No recipients required re-exploration in the other groups. In the NO ECMO group, systolic pulmonary arterial pressure (PAP) was significantly elevated during the main pulmonary artery clamp on the SLT side and it was decreased in the VA ECMO group because of the bypass flow. Interestingly, systolic PAP was significantly decreased in the VV ECMO group as well. CONCLUSIONS: VV ECMO decreases the PAP during SLT, which could be a choice for extracorporeal life support during lung transplant surgery for patients, even those with pulmonary hypertension.

Influence of Respiratory Gas Density on Tidal Volume during Mechanical Ventilation: A Laboratory Investigation and Observational Study in Children.

Fluid mechanics show that high-density gases need more energy while flowing through a tube. Thus, high-density anesthetic gases consume more energy to flow and less energy for lung inflation during general anesthesia. However, its impact has not been studied. Therefore, this study aimed to investigate the effects of high-density anesthetic gases on tidal volume in laboratory and clinical settings. In the laboratory study, a test lung was ventilated at the same pressure-controlled ventilation with 22 different gas compositions (density range, 1.22-2.27 kg/m3) using an anesthesia machine. A pneumotachometer was used to record the tidal volume of the test lung and the respiratory gas composition; it showed that the tidal volume of the test lung decreased as the respiratory gas density increased. In the clinical study, the change in tidal volume per body weight, accompanied by gas composition change (2% sevoflurane in oxygen and with 0-30-60% of N2O), was recorded in 30 pediatric patients. The median tidal volume per body weight decreased by 10% when the respiratory gas density increased from 1.41 kg/m3 to 1.70 kg/m3, indicating a significant between-group difference (P < 0.0001). In both settings, an increase in respiratory gas density decreased the tidal volume during pressure-controlled ventilation, which could be explained by the fluid dynamics theory. This study clarified the detailed mechanism of high-density anesthetic gas reduced the tidal volume during mechanical ventilation and revealed that this phenomenon occurs during pediatric anesthesia, which facilitates further understanding of the mechanics of ventilation during anesthesia practice and respiratory physiology.

Effects of oxytocin on responses to nociceptive and non-nociceptive stimulation in the upper central nervous system.

Oxytocin is known as a social bonding hormone, but it also functions as an anxiolytic or analgesic neurotransmitter. When oxytocin regulates pain or anxiousness centrally as a neurotransmitter, it is secreted by neurons and directly projected to targeted regions. Although the function of oxytocin at the spinal level is well studied, its effects at the supraspinal level are poorly understood. We aimed to investigate the effect of oxytocin at the supraspinal level in vivo using C57BL/6J (wild-type [WT]), oxytocin-deficient (Oxt-/-), oxytocin receptor-deficient (Oxtr-/-), and oxytocin receptor-Venus (OxtrVenus/+) mice lines. Response thresholds in Oxtr-/- mice in Hargreaves and von-Frey tests were significantly lower than those in WT mice, whereas open field and light/dark tests showed no significant differences. Moreover, response thresholds in Oxt-/- mice were raised to those in WT mice after oxytocin administration. Following the Hargreaves test, we observed the co-localisation of c-fos with Venus or the oxytocin receptor in the periaqueductal gray (PAG), medial amygdala (MeA), and nucleus accumbens (NAc) regions in OxtrVenus/+ mice. Furthermore, in the PAG, MeA, and NAc regions, the co-localisation of oxytocin with c-fos and gamma-aminobutyric acid was much stronger in Oxtr-/- mice than in WT mice. However, following von-Frey test, the same findings were observed only in the MeA and NAc regions. Our results suggest that oxytocin exerts its analgesic effect on painful stimulation via the PAG region and a self-protective effect on unpleasant stimulation via the MeA and NAc regions.

Successive perioperative management of laparoscopic liver resection in the reverse Trendelenburg position for a patient with Fontan physiology: a case report.

BACKGROUND: Laparoscopic surgery for a patient with Fontan physiology is challenging because pneumoperitoneum and positive pressure ventilation could decrease venous return and the accumulated partial pressure of arterial carbon dioxide (PaCO2) could increase pulmonary vascular resistance, which might lead to disruption of the hemodynamics. CASE PRESENTATION: A 25-year-old man with Fontan physiology was scheduled to undergo laparoscopic liver resection for Fontan-associated liver disease (FALD) with noninvasive monitoring of cardiac output (CO) by transpulmonary thermodilution in addition to transesophageal echocardiography. The abdominal air pressure was maintained low, and we planned to switch to open abdominal surgery promptly if hemodynamic instability became apparent because of the accumulated PaCO2 or postural change. Consequently, the pneumoperitoneum had limited influence on circulatory dynamics, but central venous pressure significantly decreased with postural change to the reverse Trendelenburg position. Laparoscopic liver resection for FALD was performed successfully with no significant changes in CO and central venous saturation. CONCLUSIONS: With strict circulation management, laparoscopic surgery for a patient with Fontan physiology can be performed safely. Comprehensive hemodynamic assessment by noninvasive transpulmonary thermodilution can provide valuable information to determine the time for shift to open abdominal surgery.

Successful Single-Lung Transplant for the Dominant Side: A Case Report.

Although single-lung transplant on the side with better lung function is challenging in patients with significantly asymmetrical lung function between the right and left sides, it sometimes can be a realistic option because of the recipient's condition and from the viewpoint of organ sharing. We report our experience with a successful case of single-lung transplant on the side with a pulmonary perfusion ratio of 89%. The transplant was performed with the patient under central venoarterial extracorporeal membrane oxygenation through a clamshell incision, and the patient had an acceptable short- and long-term outcome with a remarkable improvement of lung function.

Management of cesarean section in a patient with Fontan circulation: a case report of dramatic reduction of maternal oxygen consumption after delivery.

BACKGROUND: The anesthetic management of cesarean sections in Fontan-palliated parturients requires strict hemodynamic control. However, patient management with central venous oxygen saturation (ScvO2) and oxygen consumption (VO2) has never been reported. CASE PRESENTATION: A 30-year-old woman, who had received a total cavopulmonary connection for tricuspid atresia, was planned to undergo cesarean section at 38 weeks' gestation. During combined spinal-epidural anesthesia, ScvO2 in addition to arterial pressure-based cardiac output (APCO) and central venous pressure (CVP) was monitored, and the change of VO2 was evaluated. After delivery, her APCO was almost unchanged. However, her ScvO2 increased dramatically from 42.1 to 67.3% and her CVP increased from 9 to 11 mm Hg. The calculated mean maternal VO2 changed from 443 to 295 mL/min. CONCLUSIONS: In a cesarean section for a Fontan-palliated parturient, ScvO2 dramatically increased and maternal VO2 decreased by more than 25% after delivery.

α 1-Adrenergic Receptor Blockade by Prazosin Synergistically Stabilizes Rat Peritoneal Mast Cells.

BACKGROUND: Adrenaline quickly inhibits the release of histamine from mast cells. Besides ß 2-adrenergic receptors, several in vitro studies also indicate the involvement of α-adrenergic receptors in the process of exocytosis. Since exocytosis in mast cells can be detected electrophysiologically by the changes in the membrane capacitance (Cm), its continuous monitoring in the presence of drugs would determine their mast cell-stabilizing properties. METHODS: Employing the whole-cell patch-clamp technique in rat peritoneal mast cells, we examined the effects of adrenaline on the degranulation of mast cells and the increase in the Cm during exocytosis. We also examined the degranulation of mast cells in the presence or absence of α-adrenergic receptor agonists or antagonists. RESULTS: Adrenaline dose-dependently suppressed the GTP-γ-S-induced increase in the Cm and inhibited the degranulation from mast cells, which was almost completely erased in the presence of butoxamine, a ß 2-adrenergic receptor antagonist. Among α-adrenergic receptor agonists or antagonists, high-dose prazosin, a selective α 1-adrenergic receptor antagonist, significantly reduced the ratio of degranulating mast cells and suppressed the increase in the Cm. Additionally, prazosin augmented the inhibitory effects of adrenaline on the degranulation of mast cells. CONCLUSIONS: This study provided electrophysiological evidence for the first time that adrenaline dose-dependently inhibited the process of exocytosis, confirming its usefulness as a potent mast cell stabilizer. The pharmacological blockade of α 1-adrenergic receptor by prazosin synergistically potentiated such mast cell-stabilizing property of adrenaline, which is primarily mediated by ß 2-adrenergic receptors.

A clinical study comparing ultrasound-measured pyloric antrum cross-sectional area to computed tomography-measured gastric content volume to detect high-risk stomach in supine patients undergoing emergency abdominal surgery.

The main aim of this study was to assess whether the ultrasound examination and measurement of the pyloric antral cross-sectional area (antral-CSA) in the supine position could be useful to diagnose a full stomach using a computed tomography (CT) as a comparator in emergency patients. Immediately before general anesthesia induction in patients undergoing emergency abdominal surgery, antral-CSA was measured and the volume of the gastric contents was evaluated via ultrasound in the supine position. Gastric content volume was also calculated from a CT image taken prior to the operation. The primary outcome of this study was to determine the antral-CSA threshold of the "high-risk stomach" defined as the presence of solid/thick fluid and/or gastric content volume > 1.5 mL/kg. The secondary outcome was to evaluate the correlation between gastric content volume calculated by CT and antral-CSA. Thirty-nine patients provided consent and were included. Ten patients had gastric contents over 1.5 mL/kg, and 18 patients showed solid contents/thick fluids. The median [IQR] antral-CSA and gastric content volume were 3.82 [2.74-5.07] cm2 and 0.32 [0.09-2.08] mL/kg, respectively. The antral-CSA cutoff value of "high-risk stomach" was 3.01 cm2. This value had a sensitivity of 85%, a negative predictive value of 53%, and AUC of the ROC of 0.670 (p = 0.03). The Spearman rank-order correlation between both measures was 0.420 (p = 0.01). The correlation was improved, particularly in stomachs with solid contents/thick fluids. Antral-CSA measured in the supine position may help to assess the high-risk stomach patients undergoing emergency surgery.Trial registration: www.umin.ac.jp (UMIN 000013416). Registered 14 March 2014.