Comparison of bispectral index-guided and fixed-gas concentration techniques in desflurane and remifentanil anesthesia: A randomized controlled trial.

Anesthesia with desflurane and remifentanil can be maintained with either fixed or titrated desflurane concentration. We hypothesized that the fixed-gas concentration (FG) method would reduce the number of anesthetic titrations without hypnotic and hemodynamic instability compared to the bispectral index (BIS)-guided (BG) method. Forty-eight patients were randomly allocated to the FG or BG groups. In the FG group, desflurane vaporizer setting was fixed at 1 age-corrected minimum alveolar concentration (MAC). In the BG group, desflurane was titrated to target a BIS level at 50. Remifentanil was titrated to maintain a systolic arterial pressure (SAP) of 120 mmHg in both groups. Our primary endpoint was the hypnotic stability measured by the wobble of BIS in performance analysis, and the secondary endpoints included the wobble of SAP, mean BIS value during surgery, and the number of anesthetic titrations. The BIS in the FG group showed significantly less wobble (3.9 ± 1.1% vs 5.5 ± 1.5%, P <0.001) but lower value (33 ± 6 vs 46 ± 7, P <0.001) than BG group. The wobble of SAP showed no difference between groups [median (inter-quartile range), 5.0 (4.1-7.5)% vs 5.2 (4.2-8.3)%, P = 0.557]. The numbers of anesthetic titrations in the FG group were significantly lower than the BG group (0 ± 0 vs 8 ± 5, P<0.001 for desflurane, 13 ± 13 vs 22 ± 17, P = 0.047 for remifentanil). Less wobble in BIS and reduced anesthetic titration without hemodynamic instability during the FG technique may be practical in balanced anesthesia using desflurane and remifentanil anesthesia. Clinical trial: This study was registered at ClinicalTrials.gov (NCT02283866).

Severe hypoxemia during carinal resection in the lateral position under one-lung ventilation of a non-dependent lung: a case report.

During one-lung ventilation (OLV) in the lateral position, the dependent, ventilated lung receives more blood flow than the non-dependent, non-ventilated lung owing to gravity, improving the match of ventilation and perfusion. Conversely, in the rare clinical situations when OLV is applied to the non-dependent lung, arterial oxygenation can get worse due to considerable shunt flow to the dependent non-ventilated lung. We report a case of severe hypoxemia during carinal resection under OLV of a non-dependent lung. In this case, OLV had to be applied to the non-dependent lung in the lateral position because the bronchus of the non-dependent lung was anastomosed with the trachea, whereas the bronchus of the dependent lung had already been resected for carinal resection. The subsequent hypoxemia resulting from the shunt flow to the dependent non-ventilated lung was treated successfully by ligating the pulmonary artery of the dependent lung.

The effect of induced hypertension on neurological outcome in forebrain ischaemia model in rats.

INTRODUCTION: The present study investigated the effects of induced hypertension on hippocampal cell death after forebrain ischaemia in rats. MATERIALS AND METHODS: In this study, forebrain ischaemia was induced in 20 Sprague-Dawley rats by clamping the bilateral common carotid arteries to induce systemic hypotension for 8min. All rats then underwent reperfusion during which the induced hypertension group (n=10) received intermittent intravenous injections of phenylephrine (5µg) to maintain their mean arterial blood pressure at 20mmHg above baseline for 10min and the control group (n=10) did not receive any treatment. In both groups, the numbers of viable and apoptotic neuronal cells in the cornu ammonis 1 (CA1) area of the hippocampus were evaluated 7 days after the induction of ischaemia. RESULTS: The mean percentage of viable neuronal cells was higher in the induced hypertension group than in the control group (35% vs. 26%, respectively; p=0.004), but there was no significant difference in the proportion of apoptotic neuronal cells between the groups (57% vs. 43%, respectively; p=0.165). CONCLUSIONS: Induced hypertension significantly attenuated necrotic cell death in the hippocampal CA1 area, but apoptotic cell death was not affected.

Comparison of Needle Insertion and Guidewire Placement Techniques During Internal Jugular Vein Catheterization: The Thin-Wall Introducer Needle Technique Versus the Cannula-Over-Needle Technique.

OBJECTIVES: For needle insertion and guidewire placement during central venous catheterization, a thin-wall introducer needle technique and a cannula-over-needle technique have been used. This study compared these two techniques regarding the success rates and complications during internal jugular vein catheterization. DESIGN: Prospective, randomized, controlled study. SETTING: A university-affiliated hospital. PATIENTS: Two hundred sixty-six patients scheduled for thoracic surgery, gynecologic surgery, or major abdominal surgery, who required central venous catheterization. INTERVENTIONS: Patients were randomly assigned to either the thin-wall introducer needle group (n = 134) or the cannula-over-needle group (n = 132). Central venous catheterization was performed on the right internal jugular vein under assistance with real-time ultrasonography. Needle insertion and guidewire placement were performed using a thin-wall introducer needle technique in the thin-wall introducer needle group and a cannula-over-needle technique in the cannula-over-needle group. MEASUREMENTS AND MAIN RESULTS: The guidewire placement on the first skin puncture was regarded as a successful guidewire insertion on the first attempt. The number of puncture attempts for internal jugular vein catheterization was recorded. Internal jugular vein was assessed by ultrasonography to identify complications. The rate of successful guidewire insertion on the first attempt was higher in the thin-wall introducer needle group compared with the cannula-over-needle group (87.3% vs 77.3%; p = 0.037). There were fewer puncture attempts in the thin-wall introducer needle group than in the cannula-over-needle group (1.1 ± 0.4 vs 1.3 ± 0.6; p = 0.026). There was no significant difference in complications of internal jugular vein catheterization between the two groups. CONCLUSIONS: The thin-wall introducer needle technique showed a superior success rate for first attempt of needle and guidewire insertion and required fewer puncture attempts during internal jugular vein catheterization.

The optimal anesthetic depth for interventional neuroradiology: comparisons between light anesthesia and deep anesthesia.

BACKGROUND: This study was designed to determine the optimal anesthetic depth for the maintenance and recovery in interventional neuroradiology. METHODS: Eighty-eight patients undergoing interventional neuroradiology were randomly allocated to light anesthesia (n = 44) or deep anesthesia (n = 44) groups based on the value of the bispectral index (BIS). Anesthesia was induced with propofol, alfentanil, and rocuronium and maintained with 1-3% sevoflurane. The concentration of sevoflurane was titrated to maintain BIS at 40-49 (deep anesthesia group) or 50-59 (light anesthesia group). Phenylephrine was used to maintain the mean arterial pressure within 20% of preinduction values. Recovery times were recorded. RESULTS: The light anesthesia group had a more rapid recovery to spontaneous ventilation, eye opening, extubation, and orientation (4.1 ± 2.3 vs. 5.3 ± 1.8 min, 6.9 ± 3.2 min vs. 9.1 ± 3.2 min, 8.2 ± 3.1 min vs. 10.7 ± 3.3 min, 10.0 ± 3.9 min vs. 12.9 ± 5.5 min, all P < 0.01) compared to the deep anesthesia group. The use of phenylephrine was significantly increased in the deep anesthesia group (768 ± 184 vs. 320 ± 82 µg, P < 0.01). More patients moved during the procedure in the light anesthesia group (6/44 [14%] vs. 0/44 [0%], P = 0.026). CONCLUSIONS: BIS values between 50 and 59 for interventional neuroradiology were associated with a more rapid recovery and favorable hemodynamic response, but also with more patient movement. We suggest that maintaining BIS values between 40 and 49 is preferable for the prevention of patient movement during anesthesia for interventional neuroradiology.

Post-ischemic administration of pravastatin reduces neuronal injury by inhibiting Bax protein expression after transient forebrain ischemia in rats.

This study investigated the neuroprotective effect of pravastatin administration after forebrain ischemia in rats. Forebrain ischemia was induced by bilateral common carotid artery occlusion and systemic hypotension for 8min. Pravastatin at 1mg/kg (pravastatin group, n=10), or an identical volume of normal saline (control group, n=10), was injected 10min, and 1-4 days after reperfusion. Arterial blood gas was analyzed 10min before ischemia onset and 10min after ischemia completion. Viable and apoptotic neuronal cells were evaluated 7 days after ischemia by hematoxylin and eosin (H&E) staining and terminal deoxynucleotidyl transferase (TdT)-mediated deoxyuracil triphosphate biotin in situ nick-end labeling (TUNEL) staining of the hippocampal Cornu Ammonis area (CA1). Expression of Bcl-2 and Bax proteins was quantified by Western blot analysis. The proportion of viable neuronal cells after ischemia was greater in the pravastatin vs. control group (p<0.01), with greater expression of apoptotic cells in the control vs. pravastatin group (p<0.05). Bax protein expression was significantly decreased in the pravastatin group (p<0.05), whereas, Bcl-2 expression was increased, but not significantly (p>0.05). Our findings suggest that pravastatin administration after forebrain ischemia confers neuroprotection in rats by inhibiting Bax protein expression.

Symptomatic Hallucal Interphalangeal Sesamoid Bones Successfully Treated with Ultrasound-guided Injection - A Case Report -.

The hallucal interphalangeal sesamoid bone is usually asymptomatic, but it is not uncommon for it to be symptomatic in cases of undue pressure, overuse, or trauma. Even in symptomatic cases, however, patients often suffer for extended periods due to misdiagnosis, resulting in depression and anxiety that can steadily worsen to the extent that symptoms are sometimes mistaken for a somatoform disorder. Dynamic ultrasound-guided evaluations can be an effective means of detecting symptomatic sesamoid bones, and a simple injection of a small dose of local anesthetics mixed with steroids is an easily performed and effective treatment option in cases, for example, of tenosynovitis.

Left ventricular outflow tract obstruction with systolic anterior motion of the mitral valve in patient with pericardial effusion caused by ascending aortic dissection -A case report-.

Left ventricular outflow tract (LVOT) obstruction with systolic anterior motion (SAM) of mitral valve is not only limited to patients with hypertrophic cardiomyopathy. A diagnosis of LVOT obstruction with SAM is important because conventional inotropic support may potentially aggravate hemodynamic deterioration. We present a case of LVOT obstruction with SAM in a patient who underwent an emergent surgery for ascending aortic dissection with pericardial effusion. The patient showed refractory hypotension after standard pharmacologic interventions during induction of anesthesia. Transesophageal echocardiography (TEE) revealed LVOT obstruction with SAM and it was managed appropriately under the guidance of TEE. Intraoperative TEE can play an important role in diagnosis and management of LVOT obstruction with SAM caused by pericardial effusion.