Hyungseok Seo

Acute kidney injury after infrarenal abdominal aortic aneurysm surgery: a comparison of AKIN and RIFLE criteria for risk prediction

BACKGROUND Although both Acute Kidney Injury Network (AKIN) and risk, injury, failure, loss, and end-stage (RIFLE) kidney disease criteria are frequently used to diagnose acute kidney injury (AKI), they have rarely been compared in the diagnosis of AKI in patients undergoing surgery for infrarenal abdominal aortic aneurysm (AAA). This study investigated the incidence of, and risk factors for, AKI, defined by AKIN and RIFLE criteria, and compared their ability to predict mortality after infrarenal AAA surgery. METHODS This study examined 444 patients who underwent infrarenal AAA surgery between January 1999 and December 2011. Risk factors for AKI were assessed by multivariable analyses, and the impact of AKI on overall mortality was assessed by a Coxs proportional hazard model with inverse probability of treatment weighting (IPTW). Net reclassification improvement (NRI) was used to assess the performance of AKIN and RIFLE criteria in predicting overall mortality. RESULTS AKI based on AKIN and RIFLE criteria occurred in 82 (18.5%) and 55 (12.4%) patients, respectively. The independent risk factors for AKI were intraoperative red blood cell (RBC) transfusion and chronic kidney disease (CKD) by AKIN criteria, and age, intraoperative RBC transfusion, preoperative atrial fibrillation, and CKD by RIFLE criteria. After IPTW adjustment, AKI was related to 30 day mortality and overall mortality. NRI was 15.2% greater (P=0.04) for AKIN than for RIFLE criteria in assessing the risk of overall mortality. CONCLUSIONS Although AKI defined by either AKIN or RIFLE criteria was associated with overall mortality, AKIN criteria showed better prediction of mortality in patients undergoing infrarenal AAA surgery.

Noninvasive estimation of raised intracranial pressure using ocular ultrasonography in liver transplant recipients with acute liver failure -A report of two cases-

Intracranial pressure (ICP) monitoring is an important issue for liver transplant recipients, since increased ICP is associated with advanced hepatic encephalopathy or graft reperfusion during liver transplantation. Invasive monitoring of ICP is known as a gold standard method, but it can provoke bleeding and infection; thus, its use is a controversial issue. Studies have shown that optic nerve sheath diameter > 5 mm by ocular ultrasonography is useful for evaluating ICP > 20 mmHg noninvasively in many clinical settings. In this case report, we present experiences of using ocular ultrasound as a diagnostic tool that could detect changes in ICP noninvasively during liver transplantation.

Sonographic optic nerve sheath diameter as a surrogate measure for intracranial pressure in anesthetized patients in the Trendelenburg position

BackgroundIt remains to be elucidated whether the Trendelenburg position increases intracranial pressure (ICP). ICP can be evaluated by measuring the sonographic optic nerve sheath diameter (ONSD). We investigated the effect of the isolated Trendelenburg position on ONSD in patients undergoing robot-assisted laparoscopic radical prostatectomy. Additionally, we evaluated the effect of the Trendelenburg position combined with pneumoperitoneum on ONSD.MethodsTwenty-one patients scheduled for robot-assisted laparoscopic radical prostatectomy were enrolled. Sonographic ONSDs and hemodynamic parameters were measured at specific time points: in the supine position after induction of anesthesia, 3 min after the steep Trendelenburg position (35° incline), 3 min after the steep Trendelenburg position combined with pneumoperitoneum, and in the supine position after desufflation of the pneumoperitoneum.ResultsThe ONSD 3 min after the steep Trendelenburg position was significantly higher than that of the supine position after induction of anesthesia (5.1 ± 0.3 mm vs. 4.5 ± 0.4 mm). In addition, the ONSD 3 min after the steep Trendelenburg position combined with pneumoperitoneum was higher than that of the supine position after induction of anesthesia (4.9 ± 0.4 mm vs. 4.5 ± 0.4 mm). The ONSD in the supine position after desufflation of the pneumoperitoneum was similar to that in the supine position after induction of anesthesia.ConclusionsUse of the isolated steep Trendelenburg position, for even a short duration, increased the sonographic ONSD, providing a better understanding of the effect of only a transient steep Trendelenburg position on ONSD as a surrogate measure for ICP.

Dynamic optic nerve sheath diameter responses to short-term hyperventilation measured with sonography in patients under general anesthesia

Background Rapid evaluation and management of intracranial pressure (ICP) can help to early detection of increased ICP and improve postoperative outcomes in neurocritically-ill patients. Sonographic measurement of optic nerve sheath diameter (ONSD) is a non-invasive method of evaluating increased intracranial pressure at the bedside. In the present study, we hypothesized that sonographic ONSD, as a surrogate of ICP change, can be dynamically changed in response to carbon dioxide change using short-term hyperventilation. Methods Fourteen patients were enrolled. During general anesthesia, end-tidal carbon dioxide concentration (ETCO2) was decreased from 40 mmHg to 30 mmHg within 10 minutes. ONSD, which was monitored continuously in the single sonographic plane, was repeatedly measured at 1 and 5 minutes with ETCO2 40 mmHg (time-point 1 and 2) and measured again at 1 and 5 minutes with ETCO2 30 mmHg (time-point 3 and 4). Results The mean ± standard deviation of ONSD sequentially measured at four time-points were 5.0 ± 0.5, 5.0 ± 0.4, 3.8 ± 0.6, and 4.0 ± 0.4 mm, respectively. ONSD was significantly decreased at time-point 3 and 4, compared with 1 and 2 (P < 0.001). Conclusions The ONSD was rapidly changed in response to ETCO2. This finding may support that ONSD may be beneficial to close ICP monitoring in response to CO2 change.

Can Stroke Volume Variation Be an Alternative to Central Venous Pressure in Patients Undergoing Kidney Transplantation

BACKGROUND Stroke volume variation (SVV) is known to be a simple and less invasive hemodynamic parameter for evaluating fluid responsiveness and preload status. Central venous pressure (CVP) has been targeted to achieve an adequate level for improving the graft perfusion and long-term graft function in kidney transplantation (KT) recipients, despite the various potential complications. The aim of this study was to investigate whether SVV could substitute for CVP in guiding intravascular volume management during KT. METHODS This retrospective study evaluated 635 patients who underwent KT because of end-stage renal disease. Hemodynamic variables including CVP and SVV were obtained before skin incision (T1), 5 minutes after iliac vein clamping (T2), and 10 minutes after renal graft reperfusion (T3). The ability of SVV to predict CVP level was investigated with receiver operating characteristic (ROC) curve analysis. RESULTS CVPs were 6.0 ± 2.6, 8.6 ± 2.7, and 9.3 ± 2.5 mm Hg, and SVVs were 6.9 ± 3.0, 5.0 ± 2.1, and 4.3 ± 2.1% at T1, T2, and T3, respectively. ROC analysis showed that the discriminative power of SVV was fairly good with an area under the ROC curve of 0.70 (95% confidence interval, 0.67-0.72) for a CVP of 8 mm Hg, and that an optimal cutoff value of SVV was 6% as an alternative to CVP of 8 mm Hg during KT. CONCLUSIONS SVV may replace CVP in the volume management of patients who have undergone KT. Our results suggest that SVV can guide volume management to improve graft perfusion at critical time points during KT.

FIBTEM of Thromboelastometry does not Accurately Represent Fibrinogen Concentration in Patients with Severe Hypofibrinogenemia During Liver Transplantation

BACKGROUND Among rotation thromboelastometry (ROTEM®) parameters, the maximum clot firmness (MCF) of EXTEM (MCFEX), INTEM (MCFIN) and FIBTEM (MCFFIB) are influenced by both the platelet count and fibrinogen concentration. We evaluated the relative contribution of laboratory variables to MCF amplitude and determined whether the severity of hypofibrinogenemia could affect the relationship between these variables during liver transplantation (LT). MATERIAL AND METHODS Retrospective ROTEM® assays with simultaneous laboratory tests in 282 patients receiving LT were analyzed. Relative contribution of platelet and fibrinogen to MCF was assessed and a subgroup analysis based on fibrinogen concentration was performed. RESULTS Platelet count accounted for 60% of the variability in both MCFEX and MCFIN, whereas fibrinogen concentration explained 12% and 9%, respectively. In subgroup analysis, platelets accounted for 56-57% of MCFEX and MCFIN variability with fibrinogen <100 mg/dL, and 59% of the variability with fibrinogen ≥100 mg/dL. Fibrinogen was the primary determinant of MCFFIB, accounting for 73% of the variability. However, in severe hypofibrinogenemia (fibrinogen<100 mg/dL), fibrinogen explained only 22% of MCFFIB variability. CONCLUSIONS Regardless of the fibrinogen concentration, the platelet count is a constant primary determinant of the MCFEX and MCFIN during LT. However, MCFFIB may predict the fibrinogen concentration less reliably in cases of severe hypofibrinogenemia.

Quantification of Both Platelet Count and Fibrinogen Concentration Using Maximal Clot Firmness of Thromboelastometry During Liver Transplantation.

BACKGROUND Rotation thromboelastometry (ROTEM®) is increasingly used in liver transplantation (LT). Of the ROTEM® parameters, maximum clot firmness (MCF) of EXTEM (MCFEXT) and INTEM (MCFINT) are influenced by both platelet count (PLT) and fibrinogen concentration (FIB), whereas MCF of FIBTEM (MCFFIB) is solely influenced by FIB. We aimed to determine whether using MCFs of thromboelastometry could reliably predict both PLT and FIB and to evaluate their relations in patients with thrombocytopenia and hypofibrinogenemia during LT. METHODS A total of 4100 retrospective ROTEM® assays with simultaneous standard laboratory tests performed during LT were analyzed in 295 patients. The optimal cut-off values of PLT and FIB according to the ROTEM® transfusion guideline were determined by area under the curve (AUC) of receiver operating characteristic (ROC) curve analysis. RESULTS MCFEXT and MCFINT showed good correlation with platelet count (r = 0.79 and 0.80, respectively, P < .001) and with fibrinogen concentration (r = 0.67 and 0.66, respectively, P < .001). MCFFIB and fibrinogen concentration were highly correlated (r = 0.84, P < .001). Additionally, PLT and FIB were calculated mathematically: PLT (/μL) = 14827 + 3.93 (MCFEXT)(2.5); FIB (mg/dL) = 63 + 0.00082 (MCFEXT)(3.0); FIB (mg/dL) = 29 + 13.3 MCFFIB. MCFEXT <35 mm predicted PLT of 43 × 10(3)/μL (AUC = 0.89) and FIB of 91 mg/dL (AUC = 0.78), whereas MCFEXT <45 mm predicted PLT of 52 × 10(3)/μL (AUC = 0.89) and FIB of 121 mg/dL (AUC = 0.86), MCFFIB <8 mm predicted FIB of 128 mg/dL (AUC = 0.94). MCFINT showed almost the same cut-off values as MCFEXT. CONCLUSIONS Both PLT and FIB can be reliably quantified by MCFs of thromboelastometry, reducing the needs for additional laboratory tests to know values of thrombocytopenia and hypofibrinogenemia in patients undergoing LT.

Anesthetic experience of a combined ABO- and Rh-incompatible living donor liver transplantation between an O Rh- recipient and a B Rh+ donor

Living donor liver transplantation (LDLT) across ABOincompatible blood types used to be discouraged because of the increased risk of acute and antibody-mediated rejection, graft loss, infection, and poor subsequent clinical outcomes. Several strategies for overcoming ABO-incompatible LDLT, such as plasmapheresis, splenectomy, rituximab, mycophenolate mofetil, and intravenous immunoglobulin (IVIG), have reduced ABO incompatibility-related complications [1]. However, little is known about combined ABO- and Rh-incompatible LDLT. We here describe a successful LDLT procedure that was performed between an O Rh- patient with hepatocellular carcinoma (HCC) and a B Rh+ donor. The patient was a 45-year-old man whose blood type was O Rh-. He presented with a history of hepatitis B and HCC. His Child-Pugh score was 6 points (class A), and his Model for EndStage Liver Disease score was also 6 points. Three weeks before LDLT, 546 mg (300 mg/m 2

Anaphylactic reactions after cisatracurium administration in two patients -a report of two cases-

Cisatracurium was initially characterized to have no evident histamine-releasing potential with excellent cardiovascular stability. However, severe anaphylactic reactions to cisatracurium that resulted in bronchospasms and cardiovascular collapse have been reported worldwide. Two cases of severe anaphylactic reactions after the administration of cisatracurium are presented. The anesthetics used in both cases were lidocaine, midazolam, propofol (microemulsion propofol in the second case), remifentanil and cisatracurium. After the administration of these drugs, bronchospasm and hypotension manifested, leading to the diagnosis of anaphylaxis and appropriate treatment. Skin intradermal testing confirmed that both cases were due to immune-mediated anaphylaxis to cisatracurium, despite the fact that neither of the patients had been exposed to the allergen previously. The anaphylaxis may be due to cross-reactivity between neuromuscular blocking agents and substances with quaternary ammonium ions. Anesthesiologists should be aware that cisatracurium has the potential to trigger severe anaphylactic reactions via an immune-mediated mechanism.

Sudden cardiovascular collapse caused by severe anaphylaxis after cisatracurium use -a case report-

Kounis syndrome is an acute coronary syndrome concurrently occurs with allergic or hypersensitivity reactions. In patient with this syndrome, inflammatory mediators released due to an allergic reaction implicate to induce coronary artery spasm and atheromatous plaque rupture. We describe a patient with coronary artery disease who developed acute perioperative myocardial infarction leading to cardiac arrest after the anaphylactic reaction to cisatracurium, which led to a suspicion of Kounis syndrome. Anesthesiologists should be aware that anaphylaxis or allergic reactions can progress to acute coronary syndrome, thereby significantly change the course of the disease.