Preoperative evaluation of systolic murmur with point-of-care echocardiography before an elective thoracic surgery - A case report -

Background@#Systolic murmur suggesting the association of aortic valve (AV) stenosis or obstructive pathology in the left ventricular outflow tract (LVOT) usually requires preoperative echocardiographic evaluation for elective surgery.Case: In a 63-year-old female patient undergoing elective thoracic surgery, the systolic murmur was auscultated on the right sternal border of the second intercostal space in the preoperative patient holding area. Point-of-care (POC) transthoracic echocardiography (TTE) demonstrated a systolic jet flow in the LVOT area. The peak systolic velocity of the continuous wave Doppler tracing, aligned to the LVOT and the AV, was approximately 1.5 m/s. The peak/mean pressure gradient was 11/6 mmHg for the AV and 9/5 mmHg for the LVOT. Anesthesia was induced under continuous TTE imaging. Intraoperative transesophageal echocardiography also confirmed the absence of any cardiac pathology. @*Conclusions@#POC echocardiography offered a thorough preoperative evaluation of an unexpectedly identified systolic murmur, avoiding a potential delay in the operation schedule for conventional preoperative echocardiographic evaluation.

Effect of ultrafiltration on whole blood coagulation profile during cardiopulmonary bypass in cardiac surgery: a retrospective analysis / 대한마취과학회지

Background@#Ultrafiltration (UF) would enhance coagulation profiles by concentrating coagulation elements during cardiopulmonary bypass (CPB) for cardiac surgery. @*Methods@#We retrospectively reviewed electronic medical records of 75 patients who had undergone cardiac surgery with rotational thromboelastometry-based coagulation management in a university hospital and analyzed the UF-induced changes in the maximum clot firmness (MCF) of extrinsically activated test with tissue factor (EXTEM) during CPB in 30 patients. @*Results@#The median volume of filtered-free water was 1,350 ml, and median hematocrit was significantly increased from 22.5% to 25.5%. As the primary measure, UF significantly increased the median MCF-EXTEM from 48.0 mm to 50.5 mm (P = 0.015, effect size r = 0.44). The area under the receiver operating characteristic curve pre-UF MCF-EXTEM for discrimination of any increase of MCF-EXTEM after applying UF was 0.89 (95% CI [0.77, 1.00], P 50.5 mm. There was a significant interaction between pre-UF MCF-EXTEM values and applying UF (P < 0.001 for the subgroup, P = 0.046 for UF, P = 0.003 for interaction). @*Conclusions@#Applying UF improved clot firmness, and the improvement was more pronounced when pre-UF MCF-EXTEM had been reduced during CPB.

The Use of Whole Blood and Low Titer Group O Whole Blood in Managing Emergency and Trauma Patients / 대한수혈학회지

Since the mid-2000s, massive blood transfusion protocols and damage control resuscitation have improved the prognosis of trauma patients. As a part of damage control resuscitation, whole blood transfusion, especially using low titer group O whole blood (LTOWB), has been widely accepted in both military and civilian trauma settings based on its safety and significant advantages in terms of efficiency and efficacy. To implement LTOWB effectively, each institution should establish relevant policies which should simultaneously consider safety and accessibility factors, including titer threshold, blood management, blood supply, and transfusion protocols for LTOWB. These policies will need to be revised through continuous audits and monitoring. Additionally, whole blood and LTOWB may benefit hemorrhagic patients in non-trauma contexts, or in rural and pre-hospital settings. Further supporting evidence for these applications is needed.

Anesthesia safety standards for operating rooms of small hospitals and surgery clinics

Access to surgical care and essential anesthesia is an integral part of universal health coverage. Also, increasing access to surgical care depends on a parallel increase in access to safe anesthesia. Today, five billion people (more than two-thirds of the world’s population) still do not have adequate, quality surgery and anesthesia care at the right time. Therefore, the World Federation of Societies of Anesthesiologists and the World Health Organization developed the International Standards for Safe Practice of Anesthesia. The standards include the following components, which are essential for the safety of patients undergoing surgical procedures: professional expertise, facilities and equipment, medications and intravenous fluids, monitoring, and anesthesia. In this article, it is emphasized that wherever and whenever possible, anesthesia should be provided, led, or overseen by an anesthesiologist. It is also strongly recommended that essential equipment is in place and adequate training to handle it safely has been provided. Unfortunately, some operating rooms of small hospitals and clinics does not meet the above standards. It may be difficult for each hospital to manage autonomously due to the lack of a unified checklist for essential standardized requirements. By introducing appropriate anesthesia safety standards in the operating rooms of small hospitals and surgery clinics, it will be possible to increase patient safety during surgery performed under general anesthesia, deep sedation, moderate sedation, or regional anesthesia. Through this process, it is expected that the mortality and morbidity rate of unexpected surgery patients can be minimized.

Remifentanil-based propofol-supplemented vs. balanced sevoflurane-sufentanil anesthesia regimens on bispectral index recovery after cardiac surgery: a randomized controlled study

Background@#The present study was to compare the potential impact of remifentanil-based propofol-supplemented anesthesia regimen vs. conventional sevoflurane-sufentanil balanced anesthesia on postoperative recovery of consciousness indicated by c) values in patients undergoing cardiac surgery. @*Methods@#Patients undergoing cardiac surgery were randomly allocated to get the remifentanil-based propofol-supplemented anesthesia employing target-controlled infusion (TCI) of remifentanil and propofol (Group-PR, n = 15) or a balanced-anesthesia employing sevoflurane-inhalation and TCI-sufentanil (Group-C, n = 19). In Group-PR, plasma concentration (Cp) of TCI-remifentanil was fixed at 20 ng/ml, and the effect-site concentration of TCI-propofol was adjusted within 0.8–2.0 μg/ml to maintain BIS value of 40–60. In Group-C, sevoflurane dosage was adjusted within 1–1.5 minimum alveolar concentration to maintain BIS of 40–60, and Cp of TCI-sufentanil was fixed at 0.4 ng/ml. The inter-group difference in the time for achieving postoperative BIS > 80 (T-BIS80) in the intensive care unit was determined as the primary outcome. The inter-group difference in the extubation time was determined as the secondary outcome. @*Results@#T-BIS80, was shorter in Group-PR than Group-C (121.4 ± 64.9 min vs. 182.9 ± 85.1 min, respectively; the difference of means –61.5 min; 95% CI –115.7 to –7.4 min; effect size 0.812; P = 0.027). The extubation time was shorter in Group-PR than in Group-C (434.7 ± 131.3 min vs. 946.6 ± 393.3 min, respectively, P < 0.001). @*Conclusions@#Compared with the conventional sevoflurane-sufentanil balanced anesthesia, the remifentanil-based propofol-supplemented anesthesia showed significantly faster postoperative conscious recovery in patients undergoing cardiac surgery.

The role of evidence-based algorithms for rotational thromboelastometry-guided bleeding management / 대한마취과학회지

Rotational thromboelastometry (ROTEM) is a point-of-care viscoelastic method and enables to assess viscoelastic profiles of whole blood in various clinical settings. ROTEM-guided bleeding management has become an essential part of patient blood management (PBM) which is an important concept in improving patient safety. Here, ROTEM testing and hemostatic interventions should be linked by evidence-based, setting-specific algorithms adapted to the specific patient population of the hospitals and the local availability of hemostatic interventions. Accordingly, ROTEM-guided algorithms implement the concept of personalized or precision medicine in perioperative bleeding management (‘theranostic’ approach). ROTEM-guided PBM has been shown to be effective in reducing bleeding, transfusion requirements, complication rates, and health care costs. Accordingly, several randomized-controlled trials, meta-analyses, and health technology assessments provided evidence that using ROTEM-guided algorithms in bleeding patients resulted in improved patient's safety and outcomes including perioperative morbidity and mortality. However, the implementation of ROTEM in the PBM concept requires adequate technical and interpretation training, education and logistics, as well as interdisciplinary communication and collaboration.

The role of evidence-based algorithms for rotational thromboelastometry-guided bleeding management / 대한마취과학회지

Rotational thromboelastometry (ROTEM) is a point-of-care viscoelastic method and enables to assess viscoelastic profiles of whole blood in various clinical settings. ROTEM-guided bleeding management has become an essential part of patient blood management (PBM) which is an important concept in improving patient safety. Here, ROTEM testing and hemostatic interventions should be linked by evidence-based, setting-specific algorithms adapted to the specific patient population of the hospitals and the local availability of hemostatic interventions. Accordingly, ROTEM-guided algorithms implement the concept of personalized or precision medicine in perioperative bleeding management (‘theranostic’ approach). ROTEM-guided PBM has been shown to be effective in reducing bleeding, transfusion requirements, complication rates, and health care costs. Accordingly, several randomized-controlled trials, meta-analyses, and health technology assessments provided evidence that using ROTEM-guided algorithms in bleeding patients resulted in improved patient's safety and outcomes including perioperative morbidity and mortality. However, the implementation of ROTEM in the PBM concept requires adequate technical and interpretation training, education and logistics, as well as interdisciplinary communication and collaboration.

Pharmacodynamic Analysis of the Influence of Propofol on Left Ventricular Long-Axis Systolic Performance in Cardiac Surgical Patients

BACKGROUND: Propofol induced a decline in the left ventricular (LV) systolic performance in non-cardiac surgery. We tested the hypothesis that propofol decreased the LV contractile function by dose dependent manner in cardiac surgery patients. METHODS: Anesthesia was maintained with target-controlled infusions of propofol and remifentanil in cardiac surgery patients. With a fixed effect-site concentration (Ce) of remifentanil (20 ng/mL) after sternotomy, the Ce of propofol was adjusted to maintain a Bispectral index of 40–60 (Ce1). Mitral annular Doppler tissue image tracings and other echocardiographic variables, including end-diastolic and end-systolic volumes, stroke volume, and mitral inflow pulse wave Doppler profile at Ce1, were recorded using transesophageal echocardiography. Echocardiographic recordings were repeated after the Ce-values of propofol were doubled and tripled at 10-minute intervals (defined as Ce2 and Ce3, respectively). Serial changes in echocardiographic variables for each Ce of propofol were assessed using generalized linear mixed effect modeling. The pharmacodynamic relationship between the Ce of propofol and peak systolic mitral annular velocity (Sm) was analyzed by logistic regression using non-linear mixed effect modeling (NONMEM). RESULTS: Means of Ce1, Ce2, and Ce3 were 0.8, 1.6, and 2.4 μg/mL, respectively, and their means of Sm (95% confidence interval) were 9.7 (9.3–10.2), 8.7 (8.2–9.1), and 7.5 cm/sec (7.0–8.0), respectively (P < 0.01). Ce values of propofol and Sm showed a significant inter-correlation and predictability (intercept, 10.8; slope–1.0 in generalized mixed linear modeling; P < 0.01). Ce values producing 10% and 20% decline of Sm with 50%-probability were 1.4 and 2.1 μg/mL, respectively. CONCLUSION: Propofol reduces LV systolic long-axis performance in a dose-dependent manner. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01826149

Isoflurane's Effect on Intraoperative Systolic Left Ventricular Performance in Cardiac Valve Surgery Patients

BACKGROUND: Isoflurane, a common anesthetic for cardiac surgery, reduced myocardial contractility in many experimental studies, few studies have determined isoflurane's direct impact on the left ventricular (LV) contractile function during cardiac surgery. We determined whether isoflurane dose-dependently reduces the peak systolic velocity of the lateral mitral annulus in tissue Doppler imaging (S′) in patients undergoing cardiac surgery. METHODS: During isoflurane-supplemented remifentanil-based anesthesia for patients undergoing cardiac surgery with preoperative LV ejection fraction greater than 50% (n = 20), we analyzed the changes of S′ at each isoflurane dose increment (1.0, 1.5, and 2.0 minimum alveolar concentration [MAC]: T1, T2, and T3, respectively) with a fixed remifentanil dosage (1.0 μg/min/kg) by using transesophageal echocardiography. RESULTS: Mean S′ values (95% confidence interval [CI]) at T1, T2, and T3 were 10.5 (8.8–12.2), 9.5 (8.3–10.8), and 8.4 (7.3–9.5) cm/s, respectively (P < 0.001 in multivariate analysis of variance test). Their mean differences at T1 vs. T2, T2 vs. T3, and T1 vs. T3 were −1.0 (−1.6, −0.3), −1.1 (−1.7, −0.6), and −2.1 (−3.1, −1.1) cm/s, respectively. Phenylephrine infusion rates were significantly increased (0.26, 0.22, and 0.47 μg/kg/min at T1, T2, and T3, respectively, P < 0.001). CONCLUSION: Isoflurane increments (1.0–2.0 MAC) dose-dependently reduced LV systolic long-axis performance during cardiac surgeries with a preserved preoperative systolic function.

Small but serious risk of perioperative steroid use / 대한마취과학회지

No abstract available.

Special considerations for general anesthesia in elderly patients

The aged population is increasing rapidly, and the range of subjects undergoing surgery under general anesthesia is also expanding. Organ dysfunction reduces physiologic reserve, and comorbidity and polypragmasy increase the risk of postoperative complications. All anesthetic agents and techniques can be employed, if individualized to each patient's condition. Careful intraoperative monitoring and proper management to maintain homeostasis can reduce the risk of complications. Experienced anesthesiologists must choose the appropriate drug and adjust the dose individually, considering the physiologic changes that take place in the elderly. Goal-directed fluid replacement is mandatory. Anesthesiologists and surgeons should understand the risks experienced by the elderly and their fragility, and will achieve optimal outcomes if they communicate and cooperate closely.

Does acute normovolemic hemodilution affect intraoperative value of serum-creatinine concentration in patients undergoing cardiac surgery

BACKGROUND: The possible impact of hemodilution during acute normovolemic hemodilution (ANH) using hydroxyethyl starch (HES) on intraoperative serum concentration of creatinine (s-Cr) has not been well investigated. METHODS: Patients undergoing cardiac surgery were randomly allocated into Group-ANH (n = 15) or Group-C (control; n = 17). In Group-ANH, 5 ml/kg whole blood was collected, and they were administered 5 ml/kg of HES 130/0.4 after anesthesia induction and before initiating cardiopulmonary bypass (CPB). In both groups, moderate hypothermic CPB was initiated using 1,600–1,800 ml of bloodless priming solution. The changes of s-Cr, blood urea nitrogen, hematocrit (Hct), electrolytes, and osmolality were determined before ANH administration (T1), after administering ANH 5 ml/kg (T2), 30 and 60 s after the initiation of CPB (T3, T4), and at the end of surgery (T5). RESULTS: In Group-ANH, the s-Cr values at T2 (median [IQR25–75%], 0.83 [0.71–1.00] mg/dl) were not significantly different compared to those at T1 (0.84 [0.64–1.00] mg/dl), while those at T3 and T4 (0.68 [0.61–0.80] and 0.76 [0.59–0.92] mg/dl, respectively) were significantly lower than those at T2 (0.83 [0.71–1.00] mg/dl, P < 0.001). Hct at T3, T4 and T5 were significantly lower than those of T1 in both groups, and those at T2 and T4 of Group-ANH were significantly lower than those of Group-C (P < 0.001). There was no significant inter-group difference in all other parameters. CONCLUSIONS: Intraoperative s-Cr was not affected by the administration of ANH 5 ml/kg, although it reduced transiently at the beginning of CPB. Further study is needed to determine the clinical relevancy of our results.

Corrigendum: Effect of muscle relaxation on the oxygenation of human skeletal muscle: a prospective in-vivo experiment using an isolated forearm technique / 대한마취과학회지

Article contained an error in Author's affiliation on 13 page. The authors apologize for any inconvenience this mistake may have caused.

Intraoperative three-dimensional transesophageal echocardiography for evaluating an unusual structure in the left ventricular outflow tract: a case report / 대한마취과학회지

Intraoperative three-dimensional (3D) transesophageal echocardiography (TEE) facilitates an understanding of the complex cardiac pathology that is not fully delineated in a two-dimensional (2D) echocardiographic evaluation, and it suggests earlier and more precise surgical planning and intraoperative decision making. In the present case, the intraoperative 2D-TEE midesophageal long-axis view indicated a significant narrowing of the left ventricular outflow tract (LVOT) area by a band-like structure that vertically traversed the middle of the LVOT and connected to the anterior mitral leaflet base and the interventricular septum. However, additional 3D-TEE images of the LVOT and their cropped and rendered 2D images showed that web-like tissue, which presumably had grown around the patch closure from a previous atrioventricular septal defect, was obstructing the LVOT partially.

Effect of muscle relaxation on the oxygenation of human skeletal muscle: a prospective in-vivo experiment using an isolated forearm technique / 대한마취과학회지

BACKGROUND: Total oxygen consumption has been found to be reduced under deep neuromuscular blockade due to a lower rate of metabolism of skeletal muscles. However, the magnitude of this effect in individual muscles has not been investigated. Thus the aim of this study was to compare the oxygenation of paralyzed versus non-paralyzed forearm muscle under tourniquet-provoked ischemia. METHODS: After ethics approval and written informed consent, 30 patients scheduled for elective hand and wrist surgery were included. Ischemia was provoked by inflation of bilateral upper arm tourniquets and muscle relaxation was achieved via intravenous administration of rocuronium 0.9 mg/kg. Bilateral tourniquets were applied to both upper arms before induction of anesthesia and near infrared spectrometry (NIRS) electrodes applied on both forearms. Muscular ischemia in an isolated (= non-paralyzed, NP) as well as a paralyzed forearm (P) was created by sequential inflation of both tourniquets before and after intravenous administration of rocuronium. Muscle oxygen saturations (SmO2) of NIRS in both forearms and their changes were determined and compared. RESULTS: Data of 30 patients (15 male, 15 female; 41.8 +/- 14.7 years) were analyzed. The speed of SmO2 decrease (50% decrease of SmO2 from baseline (median [percentiles]: NP 210 s [180/480s] vs. P 180 [180/300]) as well as the maximum decrease in SmO2 (minimum SmO2 in % (median [percentiles]: NP 20 [19/24] vs. P 21 [19/28]) were not significantly affected by neuromuscular paralysis. CONCLUSIONS: No significant effect of muscle relaxation on NIRS-assessed muscle oxygenation under tourniquet-induced ischemia was found in human forearm muscles.

Comparison of the Impact of the Anesthesia Induction Using Thiopental and Propofol on Cardiac Function for Non-Cardiac Surgery

BACKGROUND: Thiopental and propofol have been widely used for general anesthesia induction, but their impacts on cardiac function have not been well described. A recent study speculated that anesthesia induction using propofol 2 mg/kg transiently reduced left ventricular (LV) contraction by analyzing tissue Doppler-derived imaging (TDI) during induction phase. The purpose of this study was to analyze and to compare the impacts of propofol- and thiopental-induction on LV function. METHODS: Twenty-four female patients with normal LV function undergoing non-cardiac surgery were randomly administered intravenous bolus thiopental (5 mg/kg, Thiopental-group, n = 12) or propofol (2 mg/kg, Propofol-group, n = 12) for anesthesia-induction. TDI of septal mitral annular velocity during systole (S'), early diastole (e') and atrial contraction (a') were determined by transthoracic echocardiography before and 1, 3, and 5 minutes after thiopental/propofol administration (T0, T1, T2, and T3, respectively). RESULTS: The bispectral index and systolic blood pressure declined significantly during anesthesia induction in both groups, however, more depressed in Thiopental-group compared with those in Propofol-group at T2 and T3 (all, p < 0.05). Among TDI two parameters demonstrated a significant inter-group difference: the S' in propofol was lower than that in Thiopental-group at T3 (p = 0.002), and a' velocities were persistently lower in Propofol-group, compared with same time values in Thiopental-group (T1, T2, and T3: p = 0.025, 0.007, and 0.009, respectively). CONCLUSION: Anesthesia induction using propofol revealed a more persistent and profound decline of LV and atrial contraction than that using thiopental. Further studies are needed to understand the clinical implication.

Usefulness of intraoperative real-time three-dimensional transesophageal echocardiography for pre-procedural evaluation of mitral valve cleft: a case report / 대한마취과학회지

A precise pre-procedural evaluation of mitral valve (MV) pathology is essential for planning the surgical strategy for severe mitral regurgitation (MR) and preparing for the intraoperative procedure. In the present case, a 38-year-old woman was scheduled to undergo MV replacement due to severe MR. She had a history of undergoing percutaneous balloon valvuloplasty due to rheumatic mitral stenosis during a previous pregnancy. A preoperative transthoracic echocardiography suggested a tear in the mid tip of the anterior mitral leaflet. However, the "en face" view of the MV in the left atrial perspective using intraoperative real time three-dimensional transesophageal echocardiography (RT 3D-TEE) provided a different diagnosis: a torn cleft in the P2-scallop of the posterior mitral leaflet (PML) with rupture of the chordae. Thus, surgical planning was changed intraoperatively to MV repair (MVRep) consisting of patch closure of the PML, commissurotomy, and lifting annuloplasty. The present case shows that intraoperative RT 3D-TEE provides more precise and reliable spatial information of MV for MVRep and facilitates critical surgical decision-making.

Cerebral blood flow change during volatile induction in large-dose sevoflurane versus intravenous propofol induction: transcranial Doppler study / 대한마취과학회지

BACKGROUND: The impact of volatile induction using large-dose sevoflurane (VI-S) on cerebral blood flow has not been well investigated. The present study compared the changes in cerebral blood flow of middle cerebral artery using transcranial Doppler (TCD) during VI-S and conventional induction using propofol. METHODS: Patients undergoing elective lumbar discectomy were randomly allocated to receive either sevoflurane (8%, Group VI-S, n = 11) or target-controlled infusion of propofol (effect site concentration, 3.0 microg/ml; Group P, n = 11) for induction of anesthesia. The following data were recorded before and at 1, 2, and 3 min after commencement of anesthetic induction (T0, T1, T2, and T3, respectively): mean velocity of the middle cerebral artery (V(MCA)) by TCD, mean blood pressure (MBP), heart rate, bispectral index score (BIS) and end-tidal CO2 (ETCO2). Changes in V(MCA) and MBP from their values at T0 (DeltaV(MCA) and DeltaMBP) at T1, T2, and T3 were also determined. RESULTS: BISs at T1, T2 and T3 were significantly less than that at T0 in both groups (P < 0.05). DeltaVMCA in Group VI-S at T2 and T3 (18.1% and 12.4%, respectively) were significantly greater than those in Group P (-7.6% and -19.8%, P = 0.006 and P < 0.001, respectively), whereas ETCO2 and DeltaMBP showed no significant intergroup difference. CONCLUSIONS: VI-S using large-dose sevoflurane increases cerebral blood flow resulting in luxury cerebral flow-metabolism mismatch, while conventional propofol induction maintains cerebral flow-metabolism coupling. This mismatch in VI-S may have to be considered in clinical application of VI-S.

Perioperative adrenergic response and the use of beta-blockers / 대한마취과학회지

No abstract available.

Large left atrial myxoma causing mitral annular dilation, functional mitral stenosis with concealed atrial septal defects / 대한마취과학회지

No abstract available.