Agreement between continuous cardiac output measured by the fourth-generation FloTrac/Vigileo system and a pulmonary artery catheter in adult liver transplantation

In liver transplantation for end-stage liver failure, monitoring of continuous cardiac output (CCO) is used for circulatory management due to hemodynamic instability. CCO is often measured using the minimally invasive FloTrac/Vigileo system (FVS-CCO), instead of a highly invasive pulmonary artery catheter (PAC-CCO). The FVS has improved accuracy due to an updated cardiac output algorithm, but the effect of this change on the accuracy of FVS-CCO in liver transplantation is unclear. In this study, we assessed agreement between fourth-generation FVS-CCO and PAC-CCO in 20 patients aged ≥ 20 years who underwent scheduled or emergency liver transplantation at Kyoto University Hospital from September 2019 to June 2021. Consent was obtained before surgery and data were recorded throughout the surgical period. Pearson correlation coefficient (r), Bland–Altman and 4-quadrant plot analyses were performed on the extracted data. A total of 1517 PAC-CCO vs. FVS-CCO data pairs were obtained. The mean PAC-CCO was 8.73 L/min and the mean systemic vascular resistance was 617.5 dyne·s·cm⁻⁵, r was 0.48, bias was 1.62 L/min, the 95% limits of agreement were − 3.04 to 6.27, and the percentage error was 54.36%. These results show that agreement and trending between fourth-generation FVS-CCO and PAC-CCO are low in adult liver transplant recipients

Derivation and validation of an equation to determine the optimal ventilator setting in children undergoing intracranial revascularization surgery: A single-center retrospective study

Background: It can be difficult to determine the appropriate ventilator settings to maintain normocapnia in children undergoing general anesthesia for surgery for moyamoya disease, especially immediately following anesthesia induction. Aim: We conducted this study to attempt to derive an equation to predict the appropriate ventilator settings and subsequently validated the accuracy of the equation. Methods: A retrospective study of 91 pediatric patients less than 18 years of age who underwent cerebral revascularization for moyamoya disease at our institution. Fifty‐eight patients were used to derive the equation, and the subsequent 33 patients were used to validate the equation. We calculated the required respiratory rate to attain normocapnia based on the median of all values of the minute volume during normocapnia (estimated partial pressure of arterial carbon dioxide of 38‐42 mm Hg) and the assumption that the tidal volume was 8 mL/kg body weight. We derived the regression equation from the derivation data set where the required respiratory rate to attain normocapnia was represented by age. We simplified the equation by rounding coefficients to the nearest integer. The level of agreement between the respiratory rate predicted from the equation and the actual required respiratory rate was assessed in the validation group using Bland‐Altman analysis. Results: The derived equation is tidal volume = 8 mL/kg body weight, respiratory rate = 24‐age/min. Bland‐Altman analysis in the validation group revealed that the mean bias between the predicted and actual respiratory rate was 0.29 (standard deviation, 3.67). The percentage of cases where the predicted rate was within ± 10% and ± 20% of the actual rate was 42.4% and 66.7%, respectively. Conclusions: We derived and validated a simple and easily applicable equation to predict the ventilator settings required to attain normocapnia during general anesthesia in children with moyamoya disease

Invasive Respiratory or Vasopressor Support and/or Death as a Proposed Composite Outcome Measure for Perioperative Care Research

BACKGROUND: There is a need for a clinically relevant and feasible outcome measure to facilitate clinical studies in perioperative care medicine. This large-scale retrospective cohort study proposed a novel composite outcome measure comprising invasive respiratory or vasopressor support (IRVS) and death. We described the prevalence of IRVS in patients undergoing major abdominal surgery and assessed the validity of combining IRVS and death to form a composite outcome measure. METHODS: We retrospectively collected perioperative data for 2776 patients undergoing major abdominal surgery (liver, colorectal, gastric, pancreatic, or esophageal resection) at Kyoto University Hospital. We defined IRVS as requirement for mechanical ventilation for ≥24 hours postoperatively, postoperative reintubation, or postoperative vasopressor administration. We evaluated the prevalence of IRVS within 30 postoperative days and examined the association between IRVS and subsequent clinical outcomes. The primary outcome of interest was long-term survival. Multivariable Cox proportional regression analysis was performed to adjust for the baseline patient and operative characteristics. The secondary outcomes were length of hospital stay and hospital mortality. RESULTS: In total, 85 patients (3.1%) received IRVS within 30 postoperative days, 15 of whom died by day 30. Patients with IRVS had a lower long-term survival rate (1- and 3-year survival probabilities, 66.1% and 48.5% vs 95.2% and 84.0%, respectively; P < .001, log-rank test) compared to those without IRVS. IRVS was significantly associated with lower long-term survival after adjustment for the baseline patient and operative characteristics (adjusted hazard ratio, 2.72; 95% confidence interval, 1.97–3.77; P < .001). IRVS was associated with a longer hospital stay (median [interquartile range], 65 [39–326] vs 15 [12–24] days; adjusted P < .001) and a higher hospital mortality (24.7% vs 0.5%; adjusted P < .001). Moreover, IRVS was adversely associated with subsequent clinical outcomes including lower long-term survival (adjusted hazard ratio, 1.78; 95% confidence interval, 1.21–2.63; P = .004) when the analyses were restricted to 30-day survivors. CONCLUSIONS: Patients with IRVS can experience ongoing risk of serious morbidity and less long-term survival even if alive at postoperative day 30. Our findings support the validity of using IRVS and/or death as a composite outcome measure for clinical studies in perioperative care medicine

Validation of the Radford Nomogram to Estimate the Minute Volume Required to Attain Normocapnia in Patients Undergoing General Anesthesia: A Single-Center Retrospective Study

Objective: The Radford nomogram, an old mathematical chart device to estimate the required ventilation for maintaining normocapnia, remains unvalidated in patients undergoing modern, balanced anesthesia. This study aims to investigate the performance of the Radford nomogram in patients undergoing general anesthesia and derive a simple equation to estimate the minute volume required to attain normocapnia (MVnorm). Methods: This single-center retrospective study enrolled 78 patients (age ≥ 18 years) undergoing cerebral revascularization for Moyamoya disease. We defi ned MVnorm as the median of all values of the minute volume during normocapnia (estimated PaCO2: 38–42 mmHg). We examined the agreement level between the estimated minute volume using the Radford nomogram and MVnorm using the Bland–Altman analysis. Furthermore, we developed and validated a simple equation predicting MVnorm based on gender and a multiple of body weight, using a split-sample validation technique. Result: The Radford nomogram tended to overestimate MVnorm with a mean bias of 560 mL/min (95% limits of agreement, -848–1, 968 mL/min). The equation developed using data from the development group (n = 52): required minute volume (mL/min) = 85 × body weight (kg) in male patients and 70 × body weight (kg) in female patients. In the validation group (n = 26), the mean bias of this simple equation was 224 mL/min (95% limits of agreement, -1, 264–1, 712 mL/min). Conclusion: The Radford nomogram overestimates MVnorm in modern, balanced anesthesia. The simple equation using gender and a multiple of body weight yields similar predictive performance to the Radford nomogram

Association between intraoperative end-tidal carbon dioxide and postoperative nausea and vomiting in gynecologic laparoscopic surgery

Gynecologic laparoscopic surgery has a high incidence of postoperative nausea and vomiting (PONV). Studies suggest that low intraoperative end-tidal carbon dioxide (EtCO₂) is associated with an increased incidence of PONV, but the results have not been consistent among studies. This study investigated the association between intraoperative EtCO₂ and PONV in patients undergoing gynecologic laparoscopic surgeries under general anesthesia. This retrospective cohort study involved patients who underwent gynecologic laparoscopic surgeries under general anesthesia at Kyoto University Hospital. We defined low EtCO₂ as a mean EtCO₂ of < 35 mmHg. Multivariable modified Poisson regression analysis examined the association between low EtCO₂ and PONV during postoperative two days and the postoperative length of hospital stay (PLOS). Of the 739 patients, 120 (16%) had low EtCO₂, and 430 (58%) developed PONV during postoperative two days. There was no substantial association between low EtCO₂ and increased incidence of PONV (adjusted risk ratio: 0.96; 95% confidence interval [CI] 0.80–1.14; p = 0.658). Furthermore, there was no substantial association between low EtCO₂ and prolonged PLOS (adjusted difference in PLOS: 0.13; 95% CI − 1.00 to 1.28; p = 0.816). Intraoperative low EtCO₂, specifically a mean intraoperative EtCO₂ below 35 mmHg, was not substantially associated with either increased incidence of PONV or prolonged PLOS

Intraoperative hand strength as an indicator of consciousness during awake craniotomy: a prospective, observational study

握力が覚醒下開頭手術中の覚醒度の指標となる. 京都大学プレスリリース. 2022-01-11.Awake craniotomy enables mapping and monitoring of brain functions. For successful procedures, rapid awakening and the precise evaluation of consciousness are required. A prospective, observational study conducted to test whether intraoperative hand strength could be a sensitive indicator of consciousness during the awake phase of awake craniotomy. Twenty-three patients who underwent awake craniotomy were included. Subtle changes of the level of consciousness were assessed by the Japan Coma Scale (JCS). The associations of hand strength on the unaffected side with the predicted plasma concentration (Cp) of propofol, the bispectral index (BIS), and the JCS were analyzed. Hand strength relative to the preoperative maximum hand strength on the unaffected side showed significant correlations with the Cp of propofol (ρ =  − 0.219, p = 0.007), the BIS (ρ = 0.259, p = 0.002), and the JCS (τ =  − 0.508, p = 0.001). Receiver operating characteristic curve analysis for discriminating JCS 0–1 and JCS ≥ 2 demonstrated that the area under the curve was 0.76 for hand strength, 0.78 for Cp of propofol, and 0.66 for BIS. With a cutoff value of 75% for hand strength, the sensitivity was 0.76, and the specificity was 0.67. These data demonstrated that hand strength is a useful indicator for assessing the intraoperative level of consciousness during awake craniotomy

肺移植レシピエントにおける全身麻酔導入時経過の検討

京都大学0048新制・論文博士博士(医学)乙第12970号論医博第2103号新制||医||1012(附属図書館)32408新制||医||1012京都大学大学院医学研究科医学専攻(主査)教授 小池 薫, 教授 三嶋 理晃, 教授 中山 健夫学位規則第4条第2項該当Doctor of Medical ScienceKyoto UniversityDGA

Response to letter to the editor

This reply refers to the article available at https://doi.org/10.1007/s00540-019-02664-y

Near-infrared spectroscopy underestimates cerebral oxygenation in hemodialysis patients

Regional cerebral oxygen saturation (rSO₂) measured using near-infrared spectroscopy has been reported to be significantly lower in hemodialysis (HD) patients than in non-HD ones, but the mechanisms are unknown. The aim of this prospective study was to assess the accuracy of near-infrared spectroscopy to estimate cerebral oxygenation in HD patients undergoing cardiovascular surgery. Our hypothesis was that rSO₂ values would underestimate cerebral oxygenation in HD patients. This study included 113 patients (7 HD patients and 106 non-HD ones) undergoing cardiac or major aortic surgery between December 2015 and November 2017. We evaluated the validity of rSO₂ by comparing it with ipsilateral jugular venous oxygen saturation (SjvO₂). In HD and non-HD patients, rSO₂ and SjvO₂ showed a weak correlation (R2: 0.46 and 0.28 in HD and non-HD patients, respectively). Bland–Altman analysis revealed that bias (95% limits of agreement) of rSO₂ compared to SjvO₂ was − 19.2% ( − 41.7–3.3%) in HD patients and − 1.9% (− 19.3–15.5%) in non-HD ones. The large negative bias suggests that the rSO₂ values measured using near-infrared spectroscopy substantially underestimate cerebral oxygenation in HD patients