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

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 < 0.001), and its cut-off value was 50.5 mm (specificity of 81.8% and sensitivity of 84.2% in Youden's J statistic). In the secondary analyses using the cut-off value, UF significantly increased the median MCF-EXTEM from 40.5 mm to 42.5 mm in 18 patients with pre-UF MCF-EXTEM ≤ 50.5 mm. However, it did not increase MCF-EXTEM in 12 patients with pre-UF MCF-EXTEM > 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.

Sole use of dexmedetomidine for sedation and analgesia in patients undergoing endovenous thermal ablation for incompetent saphenous veins.

BACKGROUND: Dexmedetomidine have both sedative and analgesic properties without respiratory-depressant effect. This study aims to evaluate the safety and effectiveness of sedation and analgesia using dexmedetomidine for the endovenous treatment of varicose veins. METHODS: This study included 88 patients (male =38, female =50; mean age, 48.7 years) who underwent endovenous laser or radiofrequency ablation of saphenous vein. At the beginning of sedation, dexmedetomidine was administered intravenously to all patients with a loading dose of 1 µg/kg over 15 minutes, which was followed by a maintenance dose of 0.2 µg/kg/h throughout the procedure. Peripheral oxygen saturation, systolic and diastolic blood pressure, heart rate and respiratory rate, and the induction and recovery time were assessed. The degree of pain was recorded by using a 10-point visual analog scale after the procedure. Adverse events associated with sedation/analgesia were also recorded. RESULTS: Eighty-five patients responded adequately to sole use of dexmedetomidine. The mean induction time was 17.5 minutes. The mean visual analog scale pain score during the procedure was 2.3±2.0. Maximum pain scores of 4 (discomforting) or less were recorded in 69 (78.4%) patients. Six (6.8%) patients complained of pain scores in excess of 7. Systolic and diastolic blood pressure and heart rate drop between 0 and 15 minutes were 18.2/9.3 mmHg and 13.5 beat/min, respectively. Three (3.5%) patients required cessation of infusion due to significant decrease in of blood pressure or heart rate. There was no hypoxic or resuscitation event during the procedures. CONCLUSIONS: Dexmedetomidine can provide excellent sedative and analgesic effect during endovenous thermal ablation.

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.

Intraoperative echocardiographic delineation of the high take-off coronary ostia during an extensive surgical repair of the bicuspid aortic valve and dilated sinotubular junction: a case report.

BACKGROUND: This study reports the efficacy of intraoperative transesophageal echocardiography (TEE) for evaluation of high take-off coronary ostia and proximal coronary arterial flows as an alternative to preoperative coronary angiography. CASE PRESENTATION: In a 65-year old male undergoing the bicuspid aortic valve (BAV) repair and the extensive remodeling of dilated sinus and tubular junction, and preoperative coronary angiography were unsuccessfully completed due to an allergic reaction to the contrast medium. Intraoperative TEE by employing various 3-dimensional volume images of coronary ostia and Doppler tracings of the coronary arterial flows enabled a thorough pre-procedural evaluation of the high take-off coronary arteries and post-procedural evaluation by confirming the absence of any compromise in coronary arterial flow. CONCLUSION: In the present case, intraoperative application of various TEE imaging modalities enabled comprehensive evaluation of high-taking off coronary artery, as an alternative to preoperative coronary angiography, in a patient undergoing an extensive aortic valve and aortic root repair procedure.

Needle Tip Position and Bevel Direction Have No Effect in the Fluoroscopic Epidural Spreading Pattern in Caudal Epidural Injections: A Randomized Trial.

Background. Caudal epidural steroid injections (CESIs) are an effective treatment for pain. If the injection spreads in a specific pattern depending on the needle position or bevel direction, it would be possible to inject the agent into a specific and desired area. Objectives. We conducted a prospective randomized trial to determine if the needle position and bevel direction have any effect on the epidural spreading pattern in CESI. Methods. Demographic data of the patient were collected. During CESI, the needle position (middle or lateral) and direction (ventral or dorsal) were randomly allocated. Following fluoroscope-guided injection of 4 mL contrast media and 10 mL of injectates, the epidural spreading patterns (ventral or dorsal, bilateral or lateral) were imaged. Results. In the 210 CESIs performed, the needle tip position and bevel direction did not influence the epidural spreading patterns at L4-5 and L5-S1 disc levels. A history of Lumbar spine surgery was associated with a significantly limited spread to each disc level. A midline needle tip position was more effective than the lateral position in spreading to the distant disc levels. Conclusions. Neither the needle tip position nor the bevel direction affected the epidural drug spreading pattern during CESI.

Effect of Mechanical Ventilation Mode Type on Intra- and Postoperative Blood Loss in Patients Undergoing Posterior Lumbar Interbody Fusion Surgery: A Randomized Controlled Trial.

BACKGROUND: The aim of study was to evaluate the effect of mechanical ventilation mode type, pressure-controlled ventilation (PCV), or volume-controlled ventilation (VCV) on intra- and postoperative surgical bleeding in patients undergoing posterior lumbar interbody fusion (PLIF) surgery. METHODS: This was a prospective, randomized, single-blinded, and parallel study that included 56 patients undergoing PLIF and who were mechanically ventilated using PCV or VCV. A permuted block randomization was used with a computer-generated list. The hemodynamic and respiratory parameters were measured after anesthesia induction in supine position, 5 min after patients were changed from supine to prone position, at the time of skin closure, and 5 min after the patients were changed from prone to supine position. The amount of intraoperative surgical bleeding, fluid administration, urine output, and transfusion requirement were measured at the end of surgery. The amount of postoperative bleeding and transfusion requirement were recorded every 24 h for 72 h. RESULTS: The primary outcome was the amount of intraoperative surgical bleeding, and 56 patients were analyzed. The amount of intraoperative surgical bleeding was significantly less in the PCV group than that in the VCV group (median, 253.0 [interquartile range, 179.0 to 316.5] ml in PCV group vs. 382.5 [328.0 to 489.5] ml in VCV group; P < 0.001). Comparing other parameters between groups, only peak inspiratory pressure at each measurement point in PCV group was significantly lower than that in VCV group. No harmful events were recorded. CONCLUSION: Intraoperative PCV decreased intraoperative surgical bleeding in patients undergoing PLIF, which may be related to lower intraoperative peak inspiratory pressure.

Effects of sevoflurane increments on left ventricular systolic long-axis performance during sevoflurane-remifentanil anesthesia for cardiovascular surgery.

BACKGROUND: The direct impact of sevoflurane on intraoperative left ventricular (LV) systolic performance during cardiac surgery has not been fully elucidated. Peak systolic tissue Doppler velocities of the lateral mitral annulus (S') have been used to evaluate LV systolic long-axis performance. We hypothesized that incremental sevoflurane concentration (1.0-3.0 inspired-vol%) would dose-dependently reduce S' in patients undergoing cardiac surgery due to mitral or aortic insufficiency. METHODS: In 20 patients undergoing cardiac surgery in sevoflurane-remifentanil anesthesia, we analyzed intraoperative S' values which were determined after 10 min exposure to sevoflurane at 1.0, 2.0, and 3.0 inspired-vol% (T1, T2, and T3, respectively) with a fixed remifentanil dose (1.0 µg/kg/min) using transesophageal echocardiography. RESULTS: Linear mixed-effect modeling demonstrated dose-dependent declines in S' according to the end-tidal sevoflurane concentration increments (C(ET)-sevoflurane, p < 0.001): the mean value of S' reduction for each 1.0 vol%-increment of C(ET)-sevoflurane was 1.7 cm/s (95 % confidence interval 1.4-2.1 cm/s). Medians of S' at T1, T2, and T3 (9.6, 8.9, and 7.5 cm/s, respectively) also exhibited significant declines (by 6.6, 15.6, and 21.2 % for T1 vs. T2, T2 vs. T3, and T1 vs. T3, p < 0.001, =0.002, and <0.001 in Friedman pairwise comparisons, respectively). CONCLUSIONS: Administering sevoflurane as a part of a sevoflurane-remifentanil anesthesia regimen appears to dose-dependently reduce S', indicating LV systolic performance, in patients undergoing cardiac surgery. Further studies may be required to evaluate the clinical implications of these findings.

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

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.

Clinical effects of intrathecal fentanyl on shoulder tip pain in laparoscopic total extraperitoneal inguinal hernia repair under spinal anaesthesia: a double-blind, prospective, randomized controlled trial.

OBJECTIVE: The study evaluated the clinical intraoperative effects of intrathecal administration of fentanyl on shoulder tip pain in patients undergoing laparoscopic total extraperitoneal inguinal hernia repair (TEP) under spinal anaesthesia. METHODS: Patients undergoing TEP were allocated in a double-blinded, prospective, randomized manner to two groups. Spinal anaesthesia was induced by intrathecal administration of 2.8 ml of 0.5% hyperbaric bupivacaine (14 mg) in the control group and with 2.6 ml of 0.5% hyperbaric bupivacaine (13 mg) and 10 µg fentanyl (0.2 ml) in the experimental group. RESULTS: The quality of muscle relaxation, adequacy of operative space and incidence of pneumoperitoneum were similar in the two groups (n = 36 per group). Compared with the control group, the experimental group had significantly fewer cases of hypotension (12 [33.3%]) versus 23 [63.9%]) and shoulder tip pain (nine [25%] versus 18 [50%]). Intraoperative shoulder tip pain was more severe in the control group than in the experimental group. CONCLUSIONS: Addition of intrathecal fentanyl to local anaesthetic can relieve shoulder tip pain with no change in complications, especially hypotension, during TEP under spinal anaesthesia.

A Randomized Controlled Trial about the Levels of Radiation Exposure Depends on the Use of Collimation C-arm Fluoroscopic-guided Medial Branch Block.

BACKGROUND: C-arm fluoroscope has been widely used to promote more effective pain management; however, unwanted radiation exposure for operators is inevitable. We prospectively investigated the differences in radiation exposure related to collimation in Medial Branch Block (MBB). METHODS: This study was a randomized controlled trial of 62 MBBs at L3, 4 and 5. After the patient was laid in the prone position on the operating table, MBB was conducted and only AP projections of the fluoroscope were used. Based on a concealed random number table, MBB was performed with (collimation group) and without (control group) collimation. The data on the patient's age, height, gender, laterality (right/left), radiation absorbed dose (RAD), exposure time, distance from the center of the field to the operator, and effective dose (ED) at the side of the table and at the operator's chest were collected. The brightness of the fluoroscopic image was evaluated with histogram in Photoshop. RESULTS: There were no significant differences in age, height, weight, male to female ratio, laterality, time, distance and brightness of fluoroscopic image. The area of the fluoroscopic image with collimation was 67% of the conventional image. The RAD (29.9 ± 13.0, P = 0.001) and the ED at the left chest of the operators (0.53 ± 0.71, P = 0.042) and beside the table (5.69 ± 4.6, P = 0.025) in collimation group were lower than that of the control group (44.6 ± 19.0, 0.97 ± 0.92, and 9.53 ± 8.16), resepectively. CONCLUSIONS: Collimation reduced radiation exposure and maintained the image quality. Therefore, the proper use of collimation will be beneficial to both patients and operators.

Salbutamol to facilitate management of acute hyperkalemia in liver transplantation: a case report.

PURPOSE: Acute hyperkalemia is a frequent, potentially life-threatening complication in orthotopic liver transplantation (OLT). We describe a case of acute hyperkalemia during the pre-anhepatic stage that remained persistent despite conventional treatment, including calcium salts, insulin and glucose, sodium bicarbonate, and furosemide. CLINICAL FEATURES: A 50-yr-old man with end-stage hepatitis B liver cirrhosis underwent living donor liver transplantation, receiving a right lobe graft donated by his son. The initial serum potassium concentration was 4.6 mEq l(-1). Despite conventional management, the serum potassium concentration increased to 6.6 mEq l(-1), intraoperatively. Since about 90 min elapsed from the division of the hepatic artery and the portal vein to the clamping of the suprahepatic inferior vena cava, the persistent hyperkalemia may have resulted from loss of potassium from ischemic liver cells into the systemic circulation. After incorporating nebulized salbutamol, a selective beta(2)-agonist, into the combined therapeutic regimen (sodium bicarbonate and insulin with glucose), the serum potassium concentrations rapidly normalized. CONCLUSIONS: This case suggests that acute and relatively refractory hyperkalemia can develop when surgical interruption of hepatic inflow is prolonged during hepatectomy in patients undergoing OLT using the piggyback technique. In such situations, incorporating nebulized salbutamol with a conventional anti-hyperkalemia strategy can provide an effective therapeutic option to treat hyperkalemia, even during the anhepatic stage.

The effect of midazolam premedication on patient satisfaction during fiberoptic bronchoscopy under patient-controlled sedation.

BACKGROUND: Patient-controlled sedation (PCS) with propofol is a safe and effective method of attenuating discomfort during fiberoptic bronchoscopy. The purpose was to evaluate the usefulness of midazolam in addition to PCS for fiberoptic bronchoscopy. METHODS: We randomly assigned 155 patients undergoing diagnostic bronchoscopy to two groups. Group M (n = 79) received 0.03 mg/kg of midazolam for premedication while group P (n = 76) received a loading dose (0.05 ml/kg) of PCS solution composed of 200 mg (20 ml) of propofol and 1 mg (2 ml) of alfentanil. Both groups received the PCS solution 0.2 ml/kg/hr with a bolus of 1 ml and a lockout time of 1 min. Vital signs, pulmonologist satisfaction, patient satisfaction and amnesia were evaluated. RESULTS: After the insertion of the bronchoscope, there was a slight decrease of SpO2 and an increase of blood pressure and heart rate in both groups with no significant differences between the two groups. The group P required more bolus injections (1.6 +/- 1.7 in the group M vs 2.5 +/- 2.2 in group P; P < 0.05). There was no difference in the satisfaction of pulmonologists, but the satisfaction of patients was higher in the group M (P < 0.05). More patients in the group P (93%) remembered the procedure than in the group M (70%) (P < 0.05). CONCLUSIONS: PCS is an effective method for sedating patients undergoing fiberoptic bronchoscopy and midazolam provides more patient satisfaction and amnesia.

Usefulness of new technique using a disposable syringe for endotracheal tube cuff inflation.

BACKGROUND: Risk for injuries resulting from overinflated or underinflated endotracheal tube cuff warrants adequate cuff inflation technique. Thus, this study was designed to measure the actual intracuff pressures obtained by new estimation techniques. METHODS: 95 adult surgical patients requiring tracheal intubation were randomized to two groups with respect to the endotracheal tube model: Portex(R) (n = 55) and Euromedical(R) (n = 40). After induction of anesthesia, the cuff was inflated using new estimation techniques with two different syringes: PR10 or PR20 (passive release technique using a 10-ml or 20-ml syringe, respectively). Subsequently, an aneroid manometer was used to measure the actual intracuff pressures. These inflation techniques were repeated two times. A direct cuff measurement range of 25 to 40 cmH2O was used as a reference for optimal intracuff pressure. Size 7.0 mm internal diameter (ID) tubes were used for women and size 7.5 mm ID for men. RESULTS: 88 eligible patients were studied: Portex group (n = 50) and Euromedical group (n = 38). With respect to the rate of optimal cuff inflation, PR10 was significantly higher than PR20 in both groups (56% vs. 10% in Portex group; 63.2% vs. 0% in Euromedical group, respectively) (P < 0.05). CONCLUSIONS: When direct intracuff measurement is not available, a new method, named "passive release technique" using a 10-ml syringe, is a useful alternative cuff inflation method.

Anesthetic managements for correction of aortic valve regurgitation in a patient with Loeys-Dietz Syndrome: A case report.

Loeys-Dietz Syndrome (LDS) is a recently described autosomal dominant aortic aneurysm syndrome with widespread systemic involvement. It is characterized by the triad of 1) arterial tortuosity and aneurysms, 2) hypertelorism, and 3) bifid uvula or cleft palate. A 12-year-old boy with LDS was scheduled to undergo correction of aortic valve regurgitation due to aortic annuloectasia. We report our clinical experiences of a case of LDS patient with brief review of related literatures and relevant anesthetic problems.

A heated humidifier does not reduce laryngo- pharyngeal complaints after brief laryngeal mask anesthesia.

PURPOSE: Warming and humidification of inspired gases is standard care for intubated patients whose lungs are ventilated mechanically for prolonged periods. We examined whether active humidification of inspired gases might reduce laryngo-pharyngeal discomfort in patients undergoing brief laryngeal mask airway (LMA) anesthesia. METHODS: In a prospective trial, 200 adult patients undergoing elective surgery under general anesthesia were randomly assigned to receive ventilation without airway warming and exogenous humidification (Group C-control), or active warming and humidification of inspired gases (Group HUM-humidified), using a humidifier with a heated wire circuit. Inhalational anesthesia was maintained via a circle system. The temperatures and relative humidities of inspired gases were monitored continuously throughout surgery. Postoperative sore throat, dysphonia, and dysphagia were assessed one and 24 hr after anesthesia. Whenever symptoms were present, their severities were graded using a 101-point numerical rating scale. RESULTS: The mean temperature and relative humidity of the inspired gases in Group HUM were greater compared to Group C (36.1+/-0.4 degrees C and 99.5+/-0.5% vs 26.9+/-0.8 degrees C and 76.4+/-10.9%, respectively). Postoperatively, the overall frequencies of laryngeal and pharyngeal discomfort were similar in the two groups (53.8% and 54.9% in Group C vs 51.6% and 41.9% in Group HUM at one and 24 hr respectively, P>0.05). The groups were also similar with respect to the severity scores of laryngo-pharyngeal discomfort. CONCLUSION: Active warming and humidification of inspired gases has no clinically appreciable effect in reducing the incidence and severity of laryngo-pharyngeal complaints after brief (

Single-lung ventilation with a cuffed endotracheal tube in a child with a left mainstem bronchus disruption.

IMPLICATIONS: We report a case of management of ventilation during operative repair of a traumatic left mainstem bronchial disruption in a pediatric patient. With the use of a conventional cuffed endotracheal tube, with the cuff partially in the right mainstem bronchus and partially in the trachea, we successfully managed the case with single-lung ventilation.