Evaluation of the Noninvasive Estimated Continuous Cardiac Output System for Pediatric Patients: A Prospective Observational Study.

BACKGROUND: The estimated continuous cardiac output (esCCO) system is a hemodynamic monitor that uses electrocardiograms and pulse oximeter waves to noninvasively estimate cardiac output. The coefficients for esCCO measurement have been established for adult patients, but the appropriate coefficients for pediatric patients are unclear. Therefore, this study determined esCCO coefficients for pediatric patients and validated the accuracy and tracking ability of a modified esCCO system. METHODS: An initial study compared cardiac output measurements using transthoracic echocardiography and esCCO in 60 pediatric patients aged <15 years who underwent elective noncardiac surgery. Consequently, the coefficients for the esCCO measurements were redefined for pediatric patients. The main study compared cardiac output measurements between transthoracic echocardiography and modified esCCO in 80 pediatric patients. Measurements were performed pre- and postoperatively, and the accuracy and trending ability of the cardiac output measurements were evaluated using Bland-Altman analysis and a polar plot. RESULTS: The correlation coefficients between the modified esCCO and transthoracic echocardiography were 0.96 and 0.98 in the pre- and postoperative measurements, respectively. In Bland-Altman analysis, the bias (standard deviation [SD]), 95% limits of agreement, and percentage error were 0.03 (0.28), -0.53 to 0.60, and 18% in the preoperative measurement, and -0.04 (0.19), -0.42 to 0.35, and 15% in the postoperative measurement, respectively. The polar plot showed that the cardiac output changes were well tracked, with an angular bias (SD) of 2.9° (6.0°) and radial 95% limits of agreement ranging from -9.2° to 14.9°. CONCLUSIONS: Cardiac output measurement by esCCO with modified coefficients for pediatric patients showed high accuracy and tracking ability compared with cardiac output measurement by transthoracic echocardiography. This noninvasive cardiac output measurement could benefit perioperative hemodynamic monitoring in children.

Accuracy of non-invasive core temperature monitoring in infant and toddler patients: a prospective observational study.

PURPOSE: Careful perioperative temperature management is important because it influences clinical outcomes. In pediatric patients, the esophageal temperature is the most accurate indicator of core temperature. However, it requires probe insertion into the body cavity, which is mildly invasive. Therefore, a non-invasive easily and continuously temperature monitor system is ideal. This study aimed to assess the accuracy of Temple Touch Pro™ (TTP), a non-invasive temperature monitoring using the heat flux technique, compared with esophageal (Tesoph) and rectal (Trect) temperature measurements in pediatric patients, especially in infants and toddlers. METHODS: This single-center prospective observational study included 40 pediatric patients (< 3 years old) who underwent elective non-cardiac surgery. The accuracy of TTP was analyzed using Bland-Altman analysis and compared with Tesoph or Trect temperature measurements. The error was within ± 0.5 °C and was considered clinically acceptable. RESULTS: The bias ± precision between TTP and Tesoph was 0.09 ± 0.28 °C, and 95% limits of agreement were - 0.48 to 0.65 °C (error within ± 0.5 °C: 94.0%). The bias ± precision between TTP and Trect was 0.41 ± 0.38 °C and 95% limits of agreement were - 0.35 to 1.17 °C (error within ± 0.5 °C: 68.5%). In infants, bias ± precision with 95% limits of agreement were 0.10 ± 0.30 °C with - 0.50 to 0.69 °C (TTP vs. Tesoph) and 0.35 ± 0.29 °C with - 0.23 to 0.92 °C (TTP vs. Trect). CONCLUSION: Core temperature measurements using TTP in infants and toddlers were more accurate with Tesoph than with Trect. In the future, non-invasive TTP temperature monitoring will help perioperative temperature management in pediatric patients.

Effect of intensive insulin therapy on inflammatory response after cardiac surgery using bedside artificial pancreas: A propensity score-matched analysis.

BACKGROUND: Perioperative hyperglycemia leads to poor postoperative clinical outcomes, including compromised immune function, cardiovascular events, and mortality. The optimal perioperative blood glucose levels during cardiac surgery remain unclear. A closed-loop glycemic control system (artificial pancreas, target blood glucose range:120-150 mg/dl) prevents postoperative inflammatory response more effectively than conventional insulin therapy (<200 mg/dl). However, the clinical effects of intensive insulin therapy with strict glycemic control (80-110 mg/dl) are controversial. This study aimed to determine whether intensive insulin therapy would further suppress postoperative inflammatory reactions. METHODS: This study analyzed 262 patients who underwent cardiovascular surgery with cardiopulmonary bypass. The patients were divided into two groups according to their target blood glucose range: 80-110 mg/dl and 120-150 mg/dl. The primary outcome was the difference in the C-reactive protein levels between the two groups. RESULTS: Propensity score matching resulted in 95 patients in each group based on their covariates. There was no difference in the postoperative maximum C-reactive protein levels between the two groups (14.81 ± 5.93 mg/dl vs. 14.34 ± 5.52 mg/dl; p = 0.571) following propensity score matching. Hypoglycemia did not occur during intensive insulin therapy. CONCLUSIONS: Intensive insulin therapy following cardiac surgery with cardiopulmonary bypass did not demonstrate significant advantages in the suppression of postoperative inflammatory reactions compared to that with mild glycemic control. However, intensive insulin therapy using an artificial pancreas was found to be safe, with no hypoglycemic events.

Accuracy of a noninvasive estimated continuous cardiac output measurement under different respiratory conditions: a prospective observational study.

PURPOSE: The estimated continuous cardiac output (esCCO) system was recently developed as a noninvasive hemodynamic monitoring alternative to the thermodilution cardiac output (TDCO). However, the accuracy of continuous cardiac output measurements by the esCCO system compared to TDCO under different respiratory conditions remains unclear. This prospective study aimed to assess the clinical accuracy of the esCCO system by continuously measuring the esCCO and TDCO. METHODS: Forty patients who had undergone cardiac surgery with a pulmonary artery catheter were enrolled. We compared the esCCO with TDCO from mechanical ventilation to spontaneous respiration through extubation. Patients undergoing cardiac pacing during esCCO measurement, those receiving treatment with an intra-aortic balloon pump, and those with measurement errors or missing data were excluded. In total, 23 patients were included. Agreement between the esCCO and TDCO measurements was evaluated using Bland-Altman analysis with a 20 min moving average of the esCCO. RESULTS: The paired esCCO and TDCO measurements (939 points before extubation and 1112 points after extubation) were compared. The respective bias and standard deviation (SD) values were 0.13 L/min and 0.60 L/min before extubation, and - 0.48 L/min and 0.78 L/min after extubation. There was a significant difference in bias before and after extubation (P < 0.001); the SD before and after extubation was not significant (P = 0.315). The percentage errors were 25.1% before extubation and 29.6% after extubation, which is the criterion for acceptance of a new technique. CONCLUSION: The accuracy of the esCCO system is clinically acceptable to that of TDCO under mechanical ventilation and spontaneous respiration.

Surgical Site Infections and Inflammatory Reaction After Cardiac Surgery; Bedside Artificial Pancreas Versus Conventional Insulin Therapy: A Propensity Score-Matched Analysis.

OBJECTIVES: Perioperative hyperglycemia is associated with poor postoperative recovery, including compromised immune function and increased risk of infection. A closed-loop glycemic control system (artificial pancreas) has demonstrated strict safe perioperative glycemic control without hypoglycemia risk. The authors hypothesized that the artificial pancreas would reduce surgical site infections (SSIs) and postoperative inflammatory reactions. This study aimed to assess the effect of the artificial pancreas on SSIs and C-reactive protein (CRP) levels after cardiac surgery. DESIGN: A single-center retrospective, propensity score-matched analysis. SETTING: A university hospital. PARTICIPANTS: In total, 295 patients who underwent cardiovascular surgery with cardiopulmonary bypass were included. INTERVENTIONS: Patients were divided into two groups: artificial pancreas (target blood glucose: 120-150 mg/dL) and intravenous insulin infusion (conventional insulin therapy, target blood glucose: <200 mg/dL). MEASUREMENTS AND MAIN RESULTS: The differences in the incidence of SSIs and CRP levels between the two groups were assessed. After 1:1 propensity score matching based on their covariates, 101 matched patients were selected from each group. The incidence of SSIs was reduced by 3%, 5% (conventional insulin therapy), and 2% (artificial pancreas), but the reduction was not statistically significant (p = 0.45). The postoperative maximum CRP level was significantly lower in the artificial pancreas group than in the conventional insulin therapy group, mean (standard deviation)14.53 (5.64) mg/dL v 16.57 (5.58) mg/dL; p = 0.01. CONCLUSIONS: The artificial pancreas did not demonstrate a significant reduction in the incidence of SSIs. However, the artificial pancreas was safe and suppressed postoperative inflammation compared with conventional insulin therapy.

Interference of a ventricular assist device with magnetic navigation during insertion of Sherlock 3CG™, a bedside peripherally inserted central catheter.

Recently, the Sherlock 3CG™ Tip Confirmation System, including a magnetic tracking system and an intracavitary electrocardiography guidance system, has been introduced for bedside peripherally inserted central catheter (PICC) insertion. Magnetic field sources interfere with the magnetic tracking system. Electromagnetic interference of the ventricular assist device (VAD) has already been reported with various devices but not on Sherlock 3CG™. We assessed the availability of the magnetic tracking system in patients with and without a VAD during Sherlock 3CG™ insertion and evaluated the rate of optimal PICC tip position. We retrospectively reviewed 99 patients who had undergone PICC insertion using Sherlock 3CG™ on the bedside at our institutional intensive care unit from February 2018 to December 2020. Patients were divided into groups with and without a VAD. The availability of magnetic navigation and the success rate of optimal catheter tip position in each group were assessed. Among 87 cases analyzed, there were 12 and 75 cases with a VAD and without a VAD, respectively. The availability of magnetic navigation during Sherlock 3CG™ insertion was significantly lower in the group with a VAD [4/12 (33%) with VAD vs. 72/75 (96%) without VAD, P < 0.001]. In addition, the rate of optimal PICC tip position was also significantly lower in the group with a VAD [6/12 (50%) vs. 63/75 (84%), P = 0.015] The VAD significantly led to magnetic tracking system failure due to its electromagnetic interference during Sherlock 3CG™ insertion and significantly reduced the success rate of PICC insertions in the optimal position.

Incidence of intraoperative anaphylaxis caused by blood products: a 12-year single-center, retrospective study.

PURPOSE: Intraoperative anaphylaxis caused by blood products is uncommon, but it is unclear whether the rarity of this reaction is attributable to the difficulty of diagnosis, underreporting, or both. We investigated the incidence of intraoperative transfusion anaphylaxis and its reporting to the hemovigilance system. METHODS: We retrospectively reviewed cases wherein general anesthesia was used at a single hospital during a 12-year period. Cases of intraoperative anaphylaxis were extracted using an electronic search strategy and determined using the recently developed grading and clinical scoring system. The causative blood products were determined by the onset duration based on literature regarding intraoperative transfusion anaphylaxis cases. RESULTS: Among the 62,146 general anesthesia cases, 22 cases of intraoperative anaphylaxis were identified, and 11 of the 22 cases received transfusions before the onset of anaphylaxis. Intraoperative transfusion anaphylaxis was defined as occurring within 30 min of transfusion. Finally, nine cases of intraoperative transfusion anaphylaxis were analyzed. The overall incidence of intraoperative transfusion anaphylaxis was 1/3,994, with the highest incidence noted for fresh frozen plasma (1/2146; 95% confidence interval [CI] 1/6610-1/920), platelet concentrate (1/2348; 95% CI 1/92,742-1/422), and red blood cells (1/22,867; 95% CI 1/903,199-1/4,105). No evidence indicated that these cases were reported to the Japanese hemovigilance system, although all intraoperative transfusion anaphylaxis cases were diagnosed by anesthesiologists. CONCLUSION: The incidence of intraoperative anaphylaxis caused by blood products was higher than that reported and may be underreported to the Japanese hemovigilance system. Further research, particularly multicenter studies, is needed to confirm our results.

Non-linear regression analysis for estimating the intraoperative motor evoked potential recovery time after bolus neuromuscular blockade.

The recovery time of the motor evoked potential (MEP) amplitude following a neuromuscular blockade (NMB) during surgery is useful for interpreting low-amplitude waveforms or selecting the baseline waveform. In this study, the MEP data of 195 orthopedic cases who received a bolus dose of rocuronium at the beginning of surgery, between June 2009 and January 2016 were used. A non-linear regression analysis was applied to MEP amplitude data of multiple patients. The time taken for 90% of the maximum-amplitude recovery was estimated from the identified time series model. The 90% amplitude recovery time was 88.6 min in the pharmacological model and 89.4 min in the logistic model. These results were included in the 95% confidence interval of the previous studies. Although MEP amplitude is relatively unstable because of anesthesia, the averaged time series model of MEP amplitude can be estimated by using a large number of data.

Comparison of Right Ventricular Function Between Patients With and Without Pulmonary Hypertension Owing to Left-Sided Heart Disease: Assessment Based on Right Ventricular Pressure-Volume Curves.

OBJECTIVES: Right ventricular (RV) failure with pulmonary hypertension (PH) is frequently encountered in patients with advanced left-sided heart disease (LHD). However, RV energetics in patients with postcapillary PH because of LHD has not been well studied. The authors investigated intraoperative RV energetics in patients with PH due to LHD based on pressure-volume curves with three-dimensional transesophageal echocardiography and pulmonary artery catheterization. DESIGN: Exploratory study. SETTING: National center. PARTICIPANTS: Thirty-three patients who underwent cardiac surgery for LHD were enrolled. Ten patients had PH (mean pulmonary artery pressure ≥ 25 mmHg). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: RV stroke work index (RVSWI) was calculated by integrating the area bounded by the pressure-volume curve. RV minute work index (RVMWI) was calculated as RVSWI × heart rate. Right ventriculo-arterial coupling was estimated as stroke volume divided by end-systolic volume (SV/ESV). The authors compared RV energetics between patients with and without PH because of LHD. RVSWI and RVMWI were significantly higher in patients with PH (690.7 mmHg·mL/m2 [601.6-737.1] v 440.9 mmHg·mL/m2 [330.8-585.3], p = 0.015, and 60,068 mmHg·mL/m2/min [35,547-68,741] v 26,351 mmHg·mL/m2/min [17,316-32,517], p = 0.011, respectively), although cardiac index was nearly identical. SV/ESV was significantly lower in patients with PH (0.520 [0.305-0.810] v 0.820 (0.650-1.090), p = 0.007). CONCLUSIONS: Although cardiac index was similar, RVSWI and RVMWI were significantly higher and SV/ESV was significantly lower in patients with PH because of LHD, suggesting that patients with postcapillary PH have inefficient RV performance.

Comparing oscillometric noninvasive and invasive intra-arterial blood pressure monitoring in term neonates under general anesthesia: A retrospective study.

BACKGROUND: Oscillometric noninvasive blood pressure and/or invasive intra-arterial blood pressure are commonly used to measure the systolic, diastolic, and mean components of blood pressure. Agreement between the two methods has been reported in adults, children, and infants, but rarely in neonates, especially under general anesthesia. AIMS: This retrospective study compared the agreement of each measured blood pressure value (oscillometric noninvasive or invasive intra-arterial blood pressure monitoring) in term neonates under general anesthesia. METHODS: Data were collected from neonates born at ≥36 weeks of gestation whose body weight was ≥2500 g and who underwent abdominal or noncardiac thoracic surgery with both oscillometric noninvasive and invasive intra-arterial blood pressure measurements from January 2015 to March 2020. The primary outcome was the agreement of systolic, diastolic, and mean blood pressure values between the two methods using Bland-Altman analysis. RESULTS: Paired blood pressure measurements (n = 1193) from 67 cases were compared. In Bland-Altman analysis, bias (standard deviation), 95% limits of agreement, and percentage error were -9.3 (8.4), -26.1-7.6, and 26.9% for systolic; 1.6 (6.5), -11.3-14.6, and 38.7% for diastolic; and -1.3 (5.8), -13.0-10.3, and 26.9% for mean blood pressure, respectively. During low blood pressure (intra-arterial mean blood pressure ≤30 mm Hg), the biases (standard deviation) of systolic, diastolic, and mean blood pressure were -11.4 (5.7), -0.7 (3.7), and -5.1 (4.2), whereas during high blood pressure (intra-arterial mean blood pressure ≥60 mm Hg), the values were 0.1 (9.7), 5.6 (9.4), and 6.4 (7.4), respectively. CONCLUSIONS: Based on the bias and percentage error, the mean blood pressure exhibited the most acceptable agreement between oscillometric noninvasive and invasive intra-arterial blood pressure monitoring in term neonates under general anesthesia. However, during hypertension or hypotension, there was a large discrepancy between the two methods.

Transverse vs. parasagittal in-plane approaches in ultrasound-guided paravertebral block using a microconvex probe: A randomised controlled trial.

BACKGROUND: Several approaches have been proposed for ultrasound-guided thoracic paravertebral block, but the best approach remains unclear. OBJECTIVE: We compared two ultrasound-guided in-plane approaches using a microconvex probe, transverse and parasagittal. We assessed whether either approach would facilitate successful catheter placement in the paravertebral space. DESIGN: Randomised controlled trial. SETTING: University hospital, July 2015 to March 2016. PATIENTS: Sixty patients scheduled to undergo thoracotomy were randomly allocated into two groups. INTERVENTIONS: A microconvex probe was placed transversely between adjacent ribs (transverse) or sagittally between adjacent transverse processes (parasagittal). When the Tuohy needle reached the paravertebral space, a catheter was inserted to a depth of 4 cm. Then, 0.5-ml radiocontrast was injected through the catheter under fluoroscopy. MAIN OUTCOME MEASURES: The primary outcome was successful catheter placement in the paravertebral space; secondary outcomes were 0 to 100 mm visual analogue scale pain score and morphine consumption in the first 24 h. RESULTS: All patients received the allocated paravertebral block. Correct catheter placement occurred in 23 (77%) and 24 patients (80%) using the transverse (n=30) and parasagittal approaches (n=30), respectively (P = 1.00). Five patients were excluded due to changes in surgical procedure. Postoperative pain, represented by median [IQR] visual analogue scale score, was 19.5 [12 to 25] at rest and 55 [44 to 77] on movement with the transverse approach (n=28) vs. 22 [12 to 33.5] at rest and 59 [41.5 to 75] on movement with the parasagittal approach (n=27) (P = 0.57 at rest, P = 0.76 on movement). Median morphine consumption was 11.5 [5 to 21] and 11 [5 to 18] mg in the transverse and parasagittal approaches, respectively (P = 0.99). CONCLUSION: There were no clinically significant differences between approaches for continuous ultrasound-guided thoracic paravertebral block using a microconvex probe, and both approaches achieved a high rate of correct catheter placement. TRIAL REGISTRATION: UMIN Clinical Trials Registry identifier: UMIN000015988.

A single paravertebral injection via a needle vs. a catheter for the spreading to multiple intercostal levels: a randomized controlled trial.

PURPOSE: Thoracic paravertebral block (TPVB) provides a unilateral nerve block at multiple intercostal levels allowing injection of a local anesthetic into paravertebral space (PVS) via a needle or catheter. However, the most effective injection method remains unclear. This study compared the real-time spread of ropivacaine between two paravertebral injection methods using thoracoscopy. METHODS: Thirty-four patients scheduled for thoracoscopic surgery were randomly allocated into the Needle or Catheter groups, and performed transverse in-plane ultrasound-guided TPVB. The Needle group received 20 ml of 0.5% ropivacaine via a needle placed into the lateral edge of PVS; the Catheter group received the same dose of ropivacaine via a catheter inserted 5 cm into PVS. The primary outcome was the spreading pattern of ropivacaine in each group. The secondary outcome was intraoperative vasopressor requirement after paravertebral injection. RESULTS: In the Needle group, all cases showed ropivacaine spread to multiple intercostal levels, mainly across the ribs. Contrastingly, the Catheter group showed variable spreading patterns; multiple intercostal levels (n = 10) [across the ribs (n = 4), anterolateral aspect of the vertebral bodies (n = 6)] or unobservable spreading (no change; n = 7) (P = 0.007). Vasopressors were required in two and ten cases in the Needle and Catheter groups, respectively (P = 0.010). CONCLUSION: Paravertebral injection via a needle typically resulted in spreading to multiple intercostal levels, especially across the ribs on the peripheral side of injection site, whereas injection via a catheter resulted in variable spreading patterns. Therefore, injections via needles are more stable.

Measurement of the Aortic Annulus Area and Diameter by Three-Dimensional Transesophageal Echocardiography in Transcatheter Aortic Valve Replacement.

OBJECTIVES: Sizing of the aortic valve is crucial for transcatheter aortic valve replacement (TAVR). Multidetector computed tomography (MDCT) is used for sizing. Recently, three-dimensional transesophageal echocardiography (3DTEE) has enabled accurate measurement of the aortic annulus area and diameter in cases that are difficult to measure. The authors compared measurements of aortic annulus areas and diameters acquired by MDCT and 3DTEE. DESIGN: Retrospective observational study. SETTING: Single national center. PARTICIPANTS: Sixty-eight patients who underwent TAVR replacement between September 2015 and March 2017. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The authors extracted and compared preoperative measurements of the aortic annulus area, as well as the long- and short-axis diameter, measured by MDCT and 3DTEE. There was no significant difference in the aortic annulus area (409 ± 74 v 414 ± 70 mm2, p = 0.15) or short-axis diameter (20.4 ± 2.0 v 20.6 ± 1.9 mm, p = 0.103) between 3DTEE and MDCT, but the long-axis diameter differed significantly (25.0 ± 2.4 v 25.8 ± 2.0 mm, p < 0.001), respectively. Prosthesis sizes based on 3DTEE and MDCT were the same, except in 3 patients who could not stay still during MDCT measurement; in those cases, prosthesis sizes based on 3DTEE were adopted. CONCLUSIONS: Measurements of the aortic annulus area and diameter in TAVR were similar between 3DTEE and MDCT. Patients who have difficulty remaining still during MDCT measurement because of dementia should have their prostheses sized based on 3DTEE measurements.

[Acute Subdural Hematoma due to the Breakage of an Epidural Catheter Left for a Long Time].

Breakage of an epidural catheter occurs rarely dur- ing the insertion or removal procedures. In previous reports, the broken epidural catheter fragment need not be removed in asymptomatic patients. However, late-onset neurological symptoms might occur. This is a case of delayed onset subdural hematoma due to a broken epidural catheter retained in the body for 18 years. We considered that the catheter fragment might induce chronic inflammation and vascular fragil- ity around the catheter. Antiplatelet therapy might lead to the hematoma because this patient took an aspirin (antiplatelet drug) for over 9 years. Antiplatelet and anticoagulant therapies are likely to be a risk of hematoma. Thus, even without neurological symptoms, it is necessary to consider the removal of the epidural catheter fragment in patients on anti- platelet and anticoagulant therapy.

Causative agent for perioperative anaphylaxis in a child with autism successfully identified using the intradermal test under general anesthesia.

BACKGROUND: The skin-prick and intradermal tests are the main diagnostic methods used to identify the causative agent in patients with suspected perioperative anaphylaxis. Although the intradermal test is more sensitive than the skin-prick test, multiple intradermal injections can be painful for children. Here, we present the case of a child with autism and suspected perioperative anaphylaxis. The causative agent was successfully identified using the intradermal test under general anesthesia. CASE PRESENTATION: An 8-year-old boy with autism developed anaphylaxis during general anesthesia for the fourth cleft lip and palate surgery. An allergic workout was performed, but both the skin-prick and basophil activation tests for suspected causative agents yielded negative results. The patient was afraid of multiple injections, and an intradermal test was performed under general anesthesia by anesthesiologists and allergists. Piperacillin was confirmed as the causative agent, and subsequent surgery using the same anesthetic agents without piperacillin was uneventful. CONCLUSIONS: Concerted efforts should be made to identify the causative agent for diagnosing perioperative anaphylaxis.

Thromboelastographic evaluation after cardiac surgery optimizes transfusion requirements in the intensive care unit: a single-center retrospective cohort study using an inverse probability weighting method.

OBJECTIVE: There are no reports from Japan showing the effects of using the thromboelastography algorithm on transfusion requirements after Intensive Care Unit (ICU) admission, and post-implementation knowledge regarding the thromboelastography algorithm under the Japanese healthcare system is insufficient. Therefore, this study aimed to clarify the effect of the TEG6s thromboelastography algorithm on transfusion requirements for patients in the ICU after cardiac surgery. METHODS: We retrospectively compared the requirements for blood transfusion up to 24 h after ICU admission using the thromboelastography algorithm (January 2021 to April 2022) (thromboelastography group; n = 201) and specialist consultation with surgeons and anesthesiologists (January 2018 to December 2020) (non-thromboelastography group; n = 494). RESULTS: There were no significant between-group differences in terms of age, height, weight, body mass index, operative procedure, duration of surgery or cardiopulmonary bypass, body temperature, or urine volume during surgical intervention. Moreover, there was no significant between-group difference in the amount of drainage at 24 h after ICU admission. However, crystalloid and urine volumes were significantly higher in the thromboelastography group than in the non-thromboelastography group. Additionally, fresh-frozen plasma (FFP) transfusion volumes were significantly lower in the thromboelastography group. However, there were no significant between-group differences in red blood cell count or platelet transfusion volume. After variable adjustment, the amount of FFP used from the operating room to 24 h after ICU admission was significantly reduced in the thromboelastography group. CONCLUSIONS: The thromboelastography algorithm optimized transfusion requirements at 24 h after admission to the ICU following cardiac surgery.

Intraoperative hypotension affects postoperative acute kidney injury depending on the invasiveness of abdominal surgery: A retrospective cohort study.

Intraoperative hypotension (IOH) or highly invasive surgery adversely affects postoperative clinical outcomes. It is, however, unclear whether IOH affects postoperative acute kidney injury (AKI) depending on the invasiveness of abdominal surgery. We speculated that IOH in highly invasive abdominal surgery is a significant risk factor for postoperative AKI. We retrospectively reviewed the data of 448 patients who underwent abdominal surgery. Patients were divided into 3 groups: highly (such as pancreaticoduodenectomy and hepatectomy), moderately (open abdominal surgery), and minimally (laparoscopic surgery) invasive surgeries. The association between the time-weighted average (TWA) of mean arterial pressure (MAP) values (≤60 and ≤ 55 mm Hg) and AKI occurrences in each group was assessed. Postoperative AKI occurred after highly, moderately, and minimally invasive surgeries in 33 of 222 (14.9%), 14 of 110 (12.7%), and 12 of 116 (10.3%) cases, respectively (P = .526). The median [interquartile range] of TWA-MAP ≤ 60 mm Hg, as an IOH parameter, was 0.94 [0.33-2.08] mm Hg in highly, 0.54 [0.16-1.46] mm Hg in moderately, and 0.14 [0.03-0.57] mm Hg in minimally invasive surgeries (P < 0001). In addition, there was a significant association between TWA-MAP and AKI in highly invasive surgery, unlike in moderately and minimally invasive surgery, with adjusted odds ratios (95% confidence interval) for TWA-MAP ≤ 60 and ≤ 55 mm Hg associated with AKI of 1.23 [1.00-1.52] (P = .049) and 1.55 [1.02-2.36] (P = .041), respectively. Intraoperative MAP ≤ 60 mm Hg in highly invasive abdominal surgery is associated with postoperative AKI, compared to moderately and minimally invasive surgeries. Additionally, low MAP thresholds in highly invasive surgery increase postoperative AKI risk.

Enteral liquid ventilation oxygenates a hypoxic pig model.

The potential of extrapulmonary ventilation pathways remains largely unexplored. Here, we assessed the enteral ventilation approach in hypoxic porcine models under controlled mechanical ventilation. 20 mL/kg of oxygenated perfluorodecalin (O2-PFD) was intra-anally delivered by a rectal tube. We simultaneously monitored arterial and pulmonary arterial blood gases every 2 min up to 30 min to determine the gut-mediated systemic and venous oxygenation kinetics. Intrarectal O2-PFD administration significantly increased the partial pressure of oxygen in arterial blood from 54.5 ± 6.4 to 61.1 ± 6.2 mmHg (mean ± SD) and reduced the partial pressure of carbon dioxide from 38.0 ± 5.6 to 34.4 ± 5.9 mmHg. Early oxygen transfer dynamics inversely correlate with baseline oxygenation status. SvO2 dynamic monitoring data indicated that oxygenation likely originated from the venous outflow of the broad segment of large intestine including the inferior mesenteric vein route. Enteral ventilation pathway offers an effective means for systemic oxygenation, thus warranting further clinical development.

Ketamine reduces the dose of remifentanil required during prolonged head and neck surgery: a propensity-matched analysis.

High-dose opioids induce hyperalgesia and tolerance, which negatively affects postoperative recovery. Prolonged surgery inevitably requires higher opioid doses. Ketamine reduces perioperative opioid consumption and prevents opioid-induced tolerance. However, its effects in cases of prolonged surgery remain unknown. This study aimed to evaluate the dose of intraoperative remifentanil, an ultrashort-acting µ-opioid agonist, administered after an intravenous ketamine bolus during prolonged head and neck surgery. This single-center, retrospective, observational study included 251 patients who underwent head and neck surgery (operation time ≥8 h) between January 2015 and December 2019. The participants were stratified into two groups: those who received an intravenous bolus of ketamine and those who did not (ketamine group and non-ketamine group, respectively). Propensity score-matching was used to match patients in a 1:1 ratio between the two groups, based on their covariates. The difference in intraoperative remifentanil dose administered between the two groups was assessed. After 1:1 propensity score-matching, 89 matched patients were selected from each group. The mean ± standard deviation dose of remifentanil administered was significantly lower in the ketamine group than in the non-ketamine group before (0.15±0.05 vs 0.17±0.05 µg/kg/min; P=0.01) and after matching (0.15±0.06 vs 0.17±0.05 µg/kg/min; P=0.03). In conclusion, intravenous ketamine administration may reduce the intraoperative dose of remifentanil required during prolonged head and neck surgery. However, further studies are required to evaluate the effect of this finding on enhanced recovery after surgery.

Risk factors for postoperative sore throat associated with i-gel™, a supraglottic airway device.

i-gel™ is a supraglottic airway device widely used for airway management during general anesthesia as an alternative to tracheal intubation. It sometimes results in a sore throat postoperatively; however, the risk factors for a postoperative sore throat caused by i-gel remain unclear. Here, we clarify the risk factors for a postoperative sore throat associated with i-gel insertion. We retrospectively reviewed the data of 426 adult patients who received general anesthesia with i-gel at our institution from January 2018 to December 2019. The incidence of postoperative sore throat and intraoperative data (size of i-gel, number of insertion attempts, total insertion time, and dose of the neuromuscular blocker and opioid) were evaluated. Logistic regression analysis was performed to identify the risk factors. Postoperative sore throat following i-gel insertion occurred in 24/426 patients (5.6%). The insertion time was significantly associated with the incidence of postoperative sore throat in the univariate analysis, but not in the multivariate analysis (P=0.519). Increased doses of neuromuscular blockers before i-gel insertion (odds ratio [OR], 5.46; 95% confidence interval [CI], 1.50-19.80; P=0.001) and reduced doses of intraoperative fentanyl (OR, 0.51; 95% CI, 0.28-0.93; P=0.028) were risk factors in the univariate and multivariate analyses. In the subgroup that used neuromuscular blockers before i-gel insertion, only an increased dose of neuromuscular blocker (OR, 17.2; 95%, CI 1.06-280; P=0.046) was an associated risk factor in the univariate and multivariate analyses. Overall, increased doses of neuromuscular blockers before i-gel insertion could contribute to the development of postoperative sore throat.