RNA-binding protein LIN28A upregulates transcription factor HIF1α by posttranscriptional regulation via direct binding to UGAU motifs.

Hypoxia-inducible factor 1α (HIF1α) is a transcription factor that regulates angiogenesis under hypoxic conditions. To investigate the posttranscriptional regulatory mechanism of HIF1α, we performed a cell-based screening to reveal potential cis-elements and the regulatory RNA-binding proteins that act as trans-factors. We found that LIN28A promoted HIF1α protein expression independently of the downregulation of microRNA let-7, which is also directly mediated by LIN28A. Transcriptome analysis and evaluation of RNA stability using RNA-seq and SLAM-seq analyses, respectively, revealed that LIN28A upregulates HIF1A expression via mRNA stabilization. To investigate the physical association of LIN28A with HIF1A mRNA, we performed enhanced crosslinking immunoprecipitation in 293FT cells and integrally analyzed the transcriptome. We observed that LIN28A associates with HIF1A mRNA via its cis-element motif "UGAU". The "UGAU" motifs are recognized by the cold shock domain of LIN28A, and the introduction of a loss-of-function mutation to the cold shock domain diminished the upregulatory activities performed by LIN28A. Finally, the microvessel density assay showed that the expression of LIN28A promoted angiogenesis in vivo. In conclusion, our study elucidated the role of LIN28A in enhancing the HIF1α axis at the posttranscription layer.

Evaluation of fibrinogen concentration by clot firmness using a dielectric blood coagulation test system.

PURPOSE: To determine if fibrinogen concentration can be evaluated by dielectric permittivity changes in dielectric blood coagulation testing (DBCM) during cardiovascular surgery with cardiopulmonary bypass (CPB). METHODS: We performed a single-center prospective observational study at a university hospital. One hundred patients undergoing cardiovascular surgery with CPB were enrolled. Whole-blood samples were obtained after weaning from CPB, and dielectric clot strength (DCS) was measured by intrinsic pathway testing with or without heparinase in DBCM. The FIBTEM test was performed during rotational thromboelastometry using the same samples, and maximum clot firmness (MCF) was evaluated. Spearman's correlation analysis was performed, and receiver operating characteristics (ROC) curve analyses were used to evaluate the performance of hypofibrinogenemia detection. RESULTS: DCS showed a strong positive correlation with plasma fibrinogen concentration (Rs = 0.76, P < 0.0001). The area under the ROC curve for evaluating plasma fibrinogen concentration < 200 mg/dL was 0.91 (95% confidence interval (CI) 0.85-0.97) for DCS, compared with 0.88 (95% CI 0.81-0.94) for FIBTEM MCF. The optimal cutoff value of DCS was 17.0 (sensitivity 94%, specificity 80%). CONCLUSIONS: DCS variables showed a significantly strong correlation with plasma fibrinogen concentration, and the diagnostic performance for hypofibrinogenemia was comparable to that for FIBTEM MCF. This novel methodology has the potential to provide a point-of-care test with sufficient accuracy for the detection of perioperative hypofibrinogenemia during cardiovascular surgery with CPB.

TEG6s Platelet Mapping assay for the estimation of plasma fibrinogen concentration during cardiovascular surgery: a single-center prospective observational study.

PURPOSE: The Activator F (ActF) test on the TEG6s Platelet Mapping assay system is a means of quantifying blood viscoelasticity caused by fibrin network formation, triggered by reptilase and factor XIII, while platelets are inhibited. This unique methodology enables the measurement of blood viscoelasticity, even in highly heparinized blood. Here, we investigated whether fibrinogen concentration could be estimated using the ActF test in blood samples obtained during cardiopulmonary bypass (CPB) and after CPB in patients undergoing cardiovascular surgery. METHODS: We performed a single-center prospective observational study at a university hospital. Forty patients aged ≥ 18 years who underwent elective cardiovascular surgery with CPB were enrolled. Blood samples were drawn after the induction of anesthesia, after declamping of the aorta during CPB, and after the reversal of heparinization using protamine (after CPB). Coagulation profiles were evaluated using the Platelet Mapping assay and standard laboratory tests. RESULTS: There were strong correlations between the maximal amplitude of clot strength (MA) in the ActF test and fibrinogen concentration in samples drawn during CPB (R = 0.84, 95% confidence interval [CI] 0.72-0.91; P < 0.001) and after CPB (R = 0.83, 95% CI 0.70-0.91; P < 0.001). The areas under the receiver-operating characteristic curve for the ActF MA for fibrinogen concentrations < 150 mg/dL were 0.86 (95% CI 0.73-1.0) during CPB and 0.98 (95% CI 0.94-1.0) after CPB. CONCLUSION: TEG6s Platelet Mapping ActF MA values strongly correlated with plasma fibrinogen concentration in highly heparinized blood during CPB and yielded highly accurate measurements of low fibrinogen concentrations.

Population pharmacokinetics of cefazolin before, during and after cardiopulmonary bypass in adult patients undergoing cardiac surgery.

PURPOSE: The aims of the present study were to establish a population pharmacokinetic (PPK) model of cefazolin for adult patients undergoing cardiac surgery with cardiopulmonary bypass (CPB) and to assess the probability of target attainment (PTA) for the prophylaxis of surgical site infection (SSI) using cefazolin. METHODS: Adult patients who underwent cardiac surgery with CPB were enrolled in the prospective study. Blood samples for plasma cefazolin assay were collected, and total and unbound drug concentrations were measured and analysed using the nonlinear mixed-effects modelling (NONMEM) software considering saturable plasma protein binding. Using the PPK model, plasma unbound cefazolin concentration-time courses with current prophylaxis protocols were simulated, and the PTA for common SSI pathogens was estimated. RESULTS: A total of 199 blood samples were obtained from 27 patients. A one-compartment model with first-order elimination plus an on/off CPB compartment best described the data. The population mean for systemic drug clearance (CL) was reduced and that for the volume of distribution (V) was increased during CPB compared with the pre-CPB values. CPB-induced hypoalbuminemia was associated with reduced maximum protein binding (Bmax). The simulation studies suggested that the current dosing protocols are insufficient for attaining PTA > 0.9 throughout surgery against pathogens with minimum inhibitory concentrations (MICs) >8 mg/L. A new dosing protocol that achieves a PTA > 0.9 for pathogens with a MIC of 16 mg/L was proposed. CONCLUSION: PPK modelling with simulation may be valuable for devising a cefazolin prophylaxis protocol for patients undergoing cardiac surgery with CPB.

Incidence and predictive factors of hypoglycemia after pheochromocytoma resection.

OBJECTIVES: To determine the incidence and preoperative risk factors of post-excisional hypoglycemia in patients undergoing pheochromocytoma resection. METHODS: Patients who underwent surgical resection of pheochromocytoma at a single institution were retrospectively enrolled in the present study. The primary end-point was the development of post-excisional hypoglycemia; that is, a serum glucose level <70 mg/dL. The serum levels of immunoreactive insulin and glucose levels during the preoperative oral glucose-tolerance test and surgery were analyzed to elucidate the mechanism of hypoglycemia. RESULTS: A total of 49 patients underwent surgical resection of pheochromocytoma, of which 21 patients (43%) developed post-excisional hypoglycemia. The incidence of hypoglycemia was not statistically different between patients with adrenal tumors and those with extra-adrenal tumors (18/41 [44%] vs 3/8 [38%], respectively, P = 0.73). There was no difference in the immunoreactive insulin/glucose ratio during the preoperative oral glucose-tolerance test between patients with and those without post-excisional hypoglycemia. The intraoperative immunoreactive insulin/glucose ratio was significantly higher in patients with hypoglycemia than in those without hypoglycemia. A higher 24-h urinary epinephrine level, but not norepinephrine level, was a predictive factor for post-excisional hypoglycemia. CONCLUSIONS: Post-excisional hypoglycemia is a frequent complication of pheochromocytoma resection, irrespective of the tumor location, and might be common in patients with epinephrine-predominant tumors. All patients undergoing resection of adrenal and extra-adrenal pheochromocytoma require intensive monitoring of serum glucose levels during and after surgery.

Cytotoxicity of propofol in human induced pluripotent stem cell-derived cardiomyocytes.

PURPOSE: Propofol infusion syndrome (PRIS) is a lethal condition caused by propofol overdose. Previous studies suggest that pathophysiological mechanisms underlying PRIS involve mitochondrial dysfunction; however, these mechanisms have not been fully elucidated. This study aimed to establish an experimental model of propofol-induced cytotoxicity using cultured human induced pluripotent stem cell (iPSC)-derived cardiomyocytes to determine the mechanisms behind propofol-induced mitochondrial dysfunction, and to evaluate the protective effects of coenzyme Q10 (CoQ10). METHODS: Human iPSC-derived cardiomyocytes were exposed to propofol (0, 2, 10, or 50 µg/ml) with or without 5 µM CoQ10. Mitochondrial function was assessed by measuring intracellular ATP, lactate concentrations in culture media, NAD+/NADH ratio, and the mitochondrial membrane potential. Propofol-induced cytotoxicity was evaluated by analysis of cell viability. Expression levels of genes associated with mitochondrial energy metabolism were determined by PCR. Intracellular morphological changes were analyzed by confocal microscopy. RESULTS: Treatment with 50 µg/ml propofol for 48 h reduced cell viability. High concentrations of propofol (≥ 10 µg/ml) induced mitochondrial dysfunction accompanied by downregulation of gene expression of PGC-1alpha and its downstream targets (NDUFS8 and SDHB, which are involved in the respiratory chain reaction; and CPT1B, which regulates beta-oxidation). Cardiomyocytes co-treated with 5 µM CoQ10 exhibited resistance to propofol-induced toxicity through recovery of gene expression. CONCLUSIONS: Propofol-induced cytotoxicity in human iPSC-derived cardiomyocytes may be associated with mitochondrial dysfunction via downregulation of PGC-1alpha-regulated genes associated with mitochondrial energy metabolism. Co-treatment with CoQ10 protected cardiomyocytes from propofol-induced cytotoxicity.

Polymyxin B hemoperfusion prevents acute kidney injury in sepsis model.

BACKGROUND: Direct hemoperfusion with a polymyxin B-immobilized column (PMX-DHP) adsorbs endotoxin and has been used for the treatment of septic shock. Yet, the mechanisms by which PMX-DHP acts on acute kidney injury are only partially understood. MATERIALS AND METHODS: Rats were anesthetized, tracheostomized, and placed on mechanical ventilation. The animals were randomized to three groups: a cecal ligation and puncture (CLP) + dummy-DHP group (n = 10), a CLP + PMX-DHP group (n = 10), and a sham group (n = 4). Four hours after CLP, a dummy-DHP or PMX-DHP was performed for 1 h. The heart rate, mean arterial pressure, arterial blood gases, and plasma concentrations of creatinine, lactate, potassium, interleukin (IL)-6, and IL-10 were measured at 0 h and 8 h. Eight hours after CLP, the kidney was harvested, and histopathologic examination was performed. The expressions of cleaved poly (ADP-ribose) polymerase (PARP) and nuclear factor (NF)-κB p65 were examined by immunohistochemistry. A terminal deoxynucleotide transferase dUTP nick-end labeling assay was performed to detect apoptotic nuclei in kidney sections. RESULTS: PMX-DHP maintained hemodynamics and the acid-base balance and significantly (P < 0.05) decreased the plasma concentrations of lactate, creatinine, potassium, IL-6, and IL-10 compared with dummy-DHP. PMX-DHP significantly (P < 0.001) attenuated the expressions of cleaved PARP and NF-κB p65 in renal tubular cells and renal tubular cell apoptosis compared with dummy-DHP. CONCLUSIONS: These findings suggest that PMX-DHP may protect against acute kidney injury not only by inhibiting the NF-κB signaling pathway but also by preventing renal tubular cell apoptosis.

[How to establish and organize research activities].

The goal of this article is to introduce how to establish and organize research activities. There are many questions to be answered to make our clinical levels higher and more sophisticated, and some of them may also trigger research activities. We have two options, clinical study and basic research, and combination of these two methods is an ideal way to find answers to these questions. Also, cutting edge methodologies often result in some breakthroughs in our research field. Collaboration with experts is helpful for application of these new methodologies, and it facilitates establishing network of researchers. Finally, based on results of many excellent studies (both basic and clinical), we design large scale randomized clinical trials, to verify whether these research products contribute to improvement in our clinical activity. Excellent results give some hints to a next series of studies, and in this context, reviewing and updating the achievements are also important. Organizing study groups facilitates these activities, and the Japanese Society of Anesthesiologists has recently started a project to activate research activity.

Elevated levels of angiopoietin-2 as a biomarker for respiratory failure after cardiac surgery.

OBJECTIVES: Angiopoietin-1 and angiopoietin-2 are important factors in regulating endothelial vascular permeability. This study evaluated perioperative changes in serum levels of angiopoietin-1 and -2 in patients undergoing cardiac surgery. DESIGN: Measurement of serum levels of angiopoietin-1 and angiopoietin-2 in samples collected during a previously conducted prospective, multicenter, observational study. SETTING: Three university hospitals. PARTICIPANTS: Eighty-four adult patients undergoing cardiac surgery. INTERVENTION: Serum levels of angiopoietins were measured at baseline, immediately after surgery, and the day after surgery (POD-1). MEASUREMENTS AND MAIN RESULTS: Serum levels of angiopoietin-2 were elevated by POD-1 (median 3.3 ng/mL, interquartile range [IQR] 2.5-4.6 ng/mL) compared with baseline (median 1.6 ng/mL, IQR 1.3-2.1 ng/mL, p < 0.0001), and angiopoietin-1 levels were decreased immediately after surgery (baseline median 23.2 ng/mL, IQR 10.2-32.8 ng/mL; postoperative median 8.0 ng/mL, IQR 1.5-13.2 ng/mL, p<0.0001). Angiopoietin-2 levels on POD-1 in patients undergoing off-pump coronary artery bypass grafting were significantly lower than those in patients undergoing aortic surgery (p = 0.0009) and valve surgery (p = 0.008). Angiopoietin-2 levels on POD-1 had a predictive performance of the area under the curve (AUC) of the receiver operating characteristic curve 0.74 for mechanical ventilation>3 days. Angiopoietin-1 levels and the angiopoietin-2/angiopoietin-1 ratio showed lower predictive performance (AUC values 0.58 and 0.68, respectively). CONCLUSIONS: Angiopoietin-2 serum levels were elevated after cardiac surgery. Elevated angiopoietin-2 had a good predictive performance for respiratory failure after cardiac surgery, perhaps reflecting the severity of lung dysfunction related to postoperative increases in vascular permeability.

[Potential influence of pre and intraoperative factors on postoperative recurrence and survival in patients undergoing radical resection of esophageal cancer].

BACKGROUND: Several papers report that preoperative and intraoperative factors influence postoperative recurrence of malignancy. The purpose of this study is to define which factors affect the recurrence and survival of patients after the surgical resection of the esophageal cancer. METHODS: Ninety five patients underwent complete elective resection of the esophageal cancer. All patients were without preoperative chemotherapy and radiotherapy. We extracted 12 parameters, and cox regression analyses were used to assess the relation of 12 factors and the outcomes of patients. The 12 factors included preoperative factors (age, sex, weight stage of cancer, ASA PS, serum creatinine and total bilirubin), intraoperative variables (duration of anesthesia, blood transfusion, fluid balance, hypotensive episodes) and surgical Apgar score. Hypotensive episodes were defined as the systolic pressure lower than 70 mmHg occurring from the introduction of anesthesia to the end of anesthesia. RESULTS: Hypotensive episodes and blood transfusion significantly affected 1 year cancer specific survival. Stage of cancer and blood transfusion affected 5 year cancer specific survival. CONCLUSIONS: We found that intraoperative hypotension affected 1-year cancer specific survival; however, the stage of cancer affected long-term survival instead of intraoperative factors. A low 5-year survival rate in esophageal cancer may have affected this result.

[A case of prolonged neuromuscular blockade possibly related to a high anti-acetylcholine receptor antibody level].

Prolonged neuromuscular blockade is a relatively common complication of general anesthesia. Some previous reports have shown that positive serum anti-acetylcholine receptor antibody (AChR Ab) might contribute to this complication. We experienced a case of a 69-year-old woman with prolonged neuromuscular blockade after laparoscopic sigmoid colectomy under general anesthesia using rocuronium. A high level of anti-AChR Ab (45 nmol x l-1) was found in postoperative examination and the patient had progressive muscle weakness for six months after the operation. Although this patient had mediastinal tumor diagnosed as thymic carcinoma two years before the operation, preoperative clinical evaluation was negative for myasthenia gravis (MG) and the tumor was in remission at the operation. These observations suggest that preoperative measurement of anti-AChR Ab level might be recommended for patients with mediastinal tumor regardless of symptoms of MG and that neuromuscular blocking agents should be administrated carefully in anti-AChR Ab positive patients under monitoring of the neuromuscular blockade.

Impact of preoperative intervention for smoking cessation on postoperative length of stay and cost for spine surgery patients: Propensity score matching analysis.

BACKGROUND: Preoperative intervention for smoking cessation reduces the prevalence of postoperative complications in spine surgery. To date, however, the impact of these interventions on the length of stay (LOS) and cost for patients is unclear. PATIENTS/METHODS: This retrospective cohort study analyzed data from 317 patients who were current smokers and underwent spine surgery between January 2014 and December 2019 at a single facility in Tokyo, Japan. Most patients (262) received preoperative intervention for smoking cessation within 60 days before spine surgery; the remaining 55 patients did not receive the intervention. The postoperative LOS was compared using propensity score matching. Patients were matched for age, gender, body mass index, surgical plan (cervical surgery, anterior approach surgery, minimally invasive surgery), preoperative comorbidities (diabetes mellitus, hypertension, ischemic cardiac disease, chronic lung disease), and recent history of steroid therapy, which yielded 48 pairs of patients. RESULTS: The length of postoperative hospital stay was significantly shorter in the intervention group (-10.60 days, [95% CI, -15.79 to -5.42]). The cost for service was significantly lower in the intervention group (coefficient, Japanese yen [JPY] -1,515,529; [95% CI, -2,130,631 to -900,426]; 110 JPY equivalent to 1 United States dollar). CONCLUSIONS: Preoperative interventions for smoking cessation may decrease postoperative hospital stay and hospitalization costs.

Acute pain and analgesic requirement after vaginal childbirth with and without neuraxial labor analgesia-Retrospective cohort study.

BACKGROUND: Few data are available on the intensity of pain that women experience during the first five days after vaginal childbirth. Moreover, it is unknown if the use of neuraxial labor analgesia has any impact on the level of postpartum pain. METHODS: We performed a retrospective cohort study based on chart review of all women who delivered vaginally at an urban teaching hospital between April 2017 and April 2019. The primary outcome was the area under the curve of pain score on numeric rating scale (NRS) documented in electronic medical records for five days postpartum (NRS-AUC5days). Secondary outcomes included peak NRS score, doses of oral and intravenous analgesics consumed during the first five days postpartum, and relevant obstetric outcomes. Logistic regression was used to examine the associations between the use of neuraxial labor analgesia and pain-related outcomes adjusting for potential confounders. RESULTS: During the study period, 778 women (38.6%) underwent vaginal delivery with neuraxial analgesia and 1240 women (61.4%) delivered without neuraxial analgesia. Median (Interquartile range) of NRS-AUC5days was 0.17 (0.12-0.24) among women who received neuraxial analgesia and 0.13 (0.08-0.19) among women who did not (p<0.001). Women who received neuraxial analgesia were more likely to require the first- and second-line analgesics postpartum than women who did not: diclofenac (87.9% vs. 73.0%, p< 0.001, respectively); acetaminophen (40.7% vs. 21.0%, p< 0.001, respectively). The use of neuraxial labor analgesia was independently associated with increased odds of having NRS-AUC5days in the highest 20 percentile (adjusted odds ratio [aOR] 2.03; 95% confidence interval [CI] 1.55-2.65), having peak NRS ≥ 4 (aOR 1.54; 95% CI 1.25-1.91) and developing hemorrhoids during the postpartum hospitalization (aOR 2.13; 95% CI 1.41-3.21) after adjusting for relevant confounders. CONCLUSION: Although women who used neuraxial labor analgesia had slightly higher pain scores and increased analgesic requirement during postpartum hospitalization, pain after vaginal childbirth was overall mild. The small elevation in the pain burden in neuraxial group does not seem to be clinically relevant and should not influence women's choice to receive labor analgesia.

Extubation by supraglottic airway after lobectomy prevents cough-associated air leaks and prolonged coughing or sore throat.

OBJECTIVES: Double-lumen endobronchial tubes (DLTs) are essential for differential lung ventilation during pulmonary lobectomy, but they are more rigid, longer, larger in diameter and irritable. Coughing at extubation sometimes causes airway and lung injury, which causes severe air leaks, prolonged cough and sore throat. We examined the prevalence of cough-associated air leaks at extubation and postoperative cough or sore throat after lobectomy and evaluated the efficacy of supraglottic airway (SGA) in preventing these complications. METHODS: Patient characteristics and operative and postoperative factors data were collected from patients who underwent pulmonary lobectomy between January 2013 and March 2022. After propensity score matching, these data were compared between the SGA and DLT groups. RESULTS: A total of 1069 patients with lung cancer (SGA, 641; DLTs, 428) were enrolled and coughing at extubation occurred in 100 (23.4%) patients in the DLT group, 65 (65.0%) showed increased cough-associated air leaks at extubation and 20 (30.8%) showed prolonged air leaks. Coughing at extubation occurred in 6 (0.9%) in the SGA group. In 193 patients from each group after propensity score matching, coughing at extubation and the associated air leak increase were significantly lower in the SGA group. Visual analogue scale of postoperative cough and sore throat on postoperative days 2, 7 and 30 were significantly lower in the SGA group. CONCLUSIONS: SGA is effective and safe for preventing cough-associated air leaks and prolonged postoperative cough or sore throat at extubation following pulmonary lobectomy.

Physical and psychological recovery after vaginal childbirth with and without epidural analgesia: A prospective cohort study.

BACKGROUND: Enhanced recovery is the gold standard in modern perioperative management, including that for cesarean deliveries. However, qualitative and quantitative data on the physical and psychological recovery of women after vaginal childbirth are limited. Whether neuraxial labor analgesia influences postpartum recovery is unknown. METHODS: Primiparous women anticipating a vaginal childbirth between January 2020 and May 2021 were enrolled. Women with major comorbidities or postpartum complications and those who underwent a cesarean delivery were excluded. Daily step count was measured using a wrist-worn activity tracker (FitbitTM Inspire HR) for 120 hours after vaginal childbirth. Subjective fatigue levels and health-related quality of life were assessed using the Multidimensional Fatigue Inventory (MFI) and EuroQol 5 Dimension 5 Level (EQ-5D-5L), respectively, at the 3rd trimester antenatal visit, on postpartum day 1 and 3, and at the one-month postpartum visit. Rest and dynamic pain scores and the location of pain were documented by participants during postpartum hospitalization. RESULTS: Among 300 women who were enrolled antenatally, 95 and 116 had a vaginal delivery without (NCB group) and with (EPL group) epidural analgesia, respectively. The median number of steps per 24 hours increased daily in both groups, and no significant difference was detected between the groups. Postpartum pain was mild overall, with median rest and dynamic pain scores being less than 4 and similar between the groups. MFI and EQ-5D-5L scores were the worst on postpartum day 1 in both groups and gradually improved to antepartum level by the one-month postpartum visit. Higher MFI score on postpartum day 1, but not the use of epidural analgesia, was associated with lower odds of achieving adequate postpartum ambulation (defined as >3500 steps between 48 and 72 hours postpartum). CONCLUSION: The use of epidural analgesia was not associated with worse recovery outcomes during postpartum hospitalization. TRIAL REGISTRATION: UMIN-CTR, #UMIN000039343, registered on January 31, 2020.

Hemolysis Precedes Urine Color Change in Patients Undergoing Open-Heart Surgery on Cardiopulmonary Bypass.

PURPOSE: Red-colored urine often occurs in patients in the perioperative period who undergo cardiac surgery using cardiopulmonary bypass (CPB). This urine color change has been utilized for approximating hemolysis during CPB without a proven relationship for ongoing hemolysis. This case series study aimed to examine the relationship between plasma free hemoglobin (Hb) levels and quantified measures of urine color. METHODS: Ten patients were enrolled in this study. Blood and urine were collected for analyses for the following time points: before surgery, two hours after the initiation of CPB, every 30 min during CPB thereafter, and 0, 2, 4, 12, and 24 hours after the completion of CPB. We measured free Hb in plasma and urine using the azide-methemoglobin method. Photographs of urine were obtained, and the luminance of the three basic colors (red/green/blue) was analyzed by quantitative luminance contrast analysis to find a correlation for hemolysis. RESULTS: Median levels of plasma free Hb were 0.015 (0.010-0.080, n = 10) g/dL at baseline. During the CPB, increases in plasma free Hb levels were measured: median plasma free Hb levels were increased to 0.100 g/dL (0.020-0.240, p = 0.039, vs. baseline, n = 9) at two hours into CPB, median and range, respectively. In contrast, increases in urinary free Hb levels and/or urine color changes were measured only after cessation of CPB in nine patients. CONCLUSION: Urine color change or elevation of urinary free Hb levels followed the elevation of plasma free Hb levels with considerable delay.

Proteolytic release of the receptor for advanced glycation end products from in vitro and in situ alveolar epithelial cells.

Although the receptor for advanced glycation end products (RAGE) has been used as a biological marker of alveolar epithelial cell injury in clinical studies, the mechanism for release of soluble RAGE from lung epithelial cells has not been well studied. Therefore, these studies were designed to determine the mechanism for release of soluble RAGE after lipopolysaccharide (LPS) challenge. For these purposes, alveolar epithelial cells from rat lungs were cultured on Transwell inserts, and LPS was added to the apical side (500 µg/ml) for 16 h on day 7. On day 7, RAGE was expressed predominantly in surfactant protein D-negative cells, and LPS challenge induced release of RAGE into the medium. This response was partially blocked by matrix metalloproteinase (MMP) inhibitors. Transcripts of MMP-3 and MMP-13 were upregulated by LPS, whereas RAGE transcripts did not change. Proteolysis by MMP-3 and MMP-13 resulted in soluble RAGE expression in the bronchoalveolar lavage fluid in the in situ rat lung, and this reaction was inhibited by MMP inhibitors. In human studies, both MMP-3 and -13 antigen levels were significantly correlated with the level of RAGE in pulmonary edema fluid samples. These results support the conclusion that release of RAGE is primarily mediated by proteolytic damage in alveolar epithelial cells in the lung, caused by proteases in acute inflammatory conditions in the distal air spaces.

Reversible cerebral vasoconstriction syndrome with limb myoclonus following intravenous administration of methylergometrine.

Neurological deficits associated with methylergometrine have been reported primarily as a result of reversible cerebral vasoconstriction syndromes (RCVS). RCVS are characterized by reversible multifocal vasoconstrictions of the cerebral arteries heralded by acute severe headache with or without neurological deficits. Here, we present the first case of suspected RCVS with transient limb myoclonus following the intravenous administration of methylergometrine during cesarean section. A 31-year-old woman who received slowly infused intravenous methylergometrine during a cesarean section suddenly reported severe occipital headache after 40 min, followed by apnea and unconsciousness for 8 min. A second administration of methylergometrine to treat the weakness of her uterine contractions resulted in a repeated loss of consciousness within minutes and the development of limb myoclonus. No abnormalities were detected by brain computerized tomography, magnetic resonance imaging, and electroencephalogram. She fully recovered spontaneously within 12 h. We consider that the transient limb myoclonus in our patient appeared as a result of RCVS caused by the intravenous administration of methylergometrine.

Retrospective analysis of spontaneous recovery from neuromuscular blockade produced by empirical use of rocuronium.

PURPOSE: A train-of-four ratio (TOF ratio) of >0.9 should be the clinical cut-off to avoid residual paralysis. However, it is not rare to extubate patients without measurement of the TOF ratio, although the safe interval from the last administration of rocuronium assuring a TOF ratio of >0.9 has not been established in the daily clinical setting. In this study, to estimate the safe interval to avoid residual paralysis, we retrospectively selected patients in whom the TOF ratio was measured during remifentanil administration before extubation, and we studied the characteristics of recovery from the neuromuscular blockade produced by the empirical use of rocuronium. METHODS: Patients undergoing surgery under general anesthesia with sevoflurane and remifentanil were studied (n = 134). Rocuronium was administered at 0.7-1.0 mg/kg for tracheal intubation, and repeated bolus administration (10 mg) or continuous infusion (15-25 mg/h) was performed by the anesthesiologists in charge of the patient to maintain intraoperative paralysis. At the end of the surgery, the TOF ratio was measured, during remifentanil infusion and the contribution of clinical parameters to spontaneous recovery from the rocuronium-induced paralysis was studied by multivariate logistic regression analyses. RESULTS: Spontaneous recovery from rocuronium-induced paralysis within 2 h after the last administration of rocuronium varied among the patients. Multivariate logistic regression analyses showed that age (P = 0.002) and time elapsed from the last administration of rocuronium (P < 0.0001) significantly contributed to TOF recovery, and elderly patients demonstrated significantly slower recovery. CONCLUSION: Because of the large variation in the recovery from rocuronium-induced paralysis, TOF-based evaluation of residual paralysis is essential to determine the appropriate indication for reversal, especially for elderly patients.

Cardiac arrest in the left lateral decubitus position and extracorporeal cardiopulmonary resuscitation during neurosurgery: a case report.

Cardiopulmonary resuscitation (CPR) in the lateral position during noncardiac surgery has been described in only a few reports in the past. Here, we report a case of cardiac arrest in a 61-year-old man undergoing microvascular decompression surgery for trigeminal neuralgia in the left lateral decubitus position. During the initial 5 min of CPR, chest compression was performed in this position by two rescuers; one from the chest and the other from the back, pushing simultaneously. Because ventricular arrhythmia was refractory to conventional CPR even after placing the patient back to the supine position, extracorporeal life support was introduced in the operating room by using the femoro-femoral approach (right atrio-femoral veno-arterial bypass). This alternative CPR markedly decreased the frequency of ventricular arrhythmia. Subsequent coronary angiogram detected 99% stenosis of the right coronary artery. Ventricular arrhythmia ceased after coronary revascularization, and the patient was successfully weaned from the extracorporeal bypass circuit. The patient was discharged alive with minimal neurological impairment. We suggest that chest compression in the lateral position by two rescuers is an efficient resuscitation maneuver, and if an electrical storm is refractory to conventional CPR, extracorporeal life support should be considered in the operating-room setting.