Anesthetic management of super-elderly patients with remimazolam: a report of two cases.

BACKGROUND: Remimazolam is a newly developed benzodiazepine with more rapid onset and offset of sedation effects than midazolam. We report elderly patients in whom a small dose of remimazolam was successfully used for general anesthesia. CASE PRESENTATION: Two elderly women (patients 1 and 2, aged 95 and 103 years, respectively) underwent hip fracture surgery under general anesthesia guided by bispectral index (BIS). Anesthesia was induced with 1.2 and 1.0 mg/kg/h and maintained with 0.2 and 0.1 mg/kg/h remimazolam, combined with fentanyl and remifentanil in patients 1 and 2, respectively. Their hemodynamics were stable with a small dose of vasopressor, and they awoke soon after the discontinuation of remimazolam without flumazenil reversal. Their postoperative courses were uneventful without any complications. Conversely, the remimazolam dose required to achieve adequate sedation were much lower than expected. CONCLUSION: Remimazolam could be useful in general anesthesia, particularly for super-elderly patients. However, the appropriate dose for induction and maintenance of anesthesia should be carefully considered based on BIS or vital signs.

Intraoperative Coronary Artery Spasm Likely Triggered by Surgical Gallbladder Manipulation: A Case Report.

Although the association between cholecystitis and acute coronary syndrome-like symptoms, including chest pain with electrocardiogram (ECG) changes, has been reported previously, it is unclear whether these symptoms can be provoked by direct stimulation to the gallbladder. We present the case of a 44-year-old man who developed coronary artery spasm (CAS) with ST-segment-elevation followed by nonsustained polymorphic ventricular tachycardia during laparoscopic cholecystectomy. The change in ECG occurred only when the gallbladder was manipulated, suggesting that direct stimulation to the gallbladder can cause CAS. Clinicians should be aware that careful ECG monitoring is necessary, especially while the gallbladder is manipulated.

Increased prothrombotic property as a risk factor of acute kidney injury after surgical repair of abdominal aortic aneurysm: a prospective observational study.

BACKGROUND: Acute kidney injury (AKI) is one of the major morbidities after surgical repair of abdominal aortic aneurysm (AAA); however, precise pathogenesis of this morbidity has not been well determined. Since prothrombotic coagulation abnormality may precede organ dysfunction in systemic inflammatory state, we examined the kinetics of von Willebrand factor (VWF) and a disintegrin-like metalloprotease with thrombospondin type 1 motif 13 (ADAMTS13), a cleaving enzyme of VWF, on the development of AKI after AAA surgery. METHODS: The kinetics of ADAMTS13 and VWF were examined in ten patients who underwent surgical repair of AAA. The changes in plasma neutrophil gelatinase-associated lipocalin (NGAL), a novel biomarker for AKI, and serum creatinine concentration were also examined at four points until seventh postoperative day (POD). Clinical diagnosis of AKI was based on the change in serum creatinine concentration and urine output according to Acute Kidney Injury Network (AKIN) criteria. RESULTS: ADAMTS13 activity was significantly lower than normal level before the surgery and showed a trend of decrease toward 3POD. The VWF/ADAMTS13 ratio showed a significant increase on 1POD, which persisted until 7POD. None of patents was diagnosed as AKI based on AKIN criteria, although two patients received furosemide and/or carperitide therapy because of decreased urine output less than 0.5 ml/kg/h for several hours in ICU. Plasma NGAL showed a trend to increase after the surgery, which was significant on 3POD. The change in plasma NGAL was significantly correlated with VWF/ADAMTS13 ratio (P < 0.01). CONCLUSIONS: This study has shown that patients undergoing AAA surgery were prothrombotic after the surgery because of high VWF/ADAMTS13 ratio. Correlation between VWF/ADAMTS13 ratio and NGAL might indicate contribution of thrombotic event to subclinical AKI in the patients undergoing AAA surgery.

[Perioperative management of a patient with anomalous origin of the left coronary artery from the pulmonary artery].

Anomalous origin of the left coronary artery from the pulmonary artery is a rare congenital disease, also known as Bland-White-Garland (BWG) syndrome. Mitral valve regurgitation secondary to papillary muscle dysfunction due to myocardial ischemia and progressive left ventricular dysfunction are major clinical manifestations of BWG syndrome. We report perioperative management of a five-year-old patient with BWG syndrome who underwent the Takeuchi procedure making an intrapulmonary baffle using anterior pulmonary artery wall. General anesthesia was maintained with inhalation of sevoflurane in 25-40% oxygen and continuous infusion of remifentanil. Since a decrease in pulmonary artery pressure could induce coronary steal phenomenon, we ventilated the patient with minimally required FI(O2) to maintain Sp(O2) 98-100%, and maintained Pa(CO2) between 40 and 50 mmHg to avoid myocardial ischemia before the induction of cardiopulmonary bypass (CPB). We started continuous infusions of nitroglycerin and milrinone after the initiation of CPB, which were continued through the post-CPB period. The patient was transferred to the ICU and the postoperative course was uneventful. There are two key points in the management of BWG syndrome : the balance between systemic and pulmonary artery pressure in pre-CPB period, and left ventricular support including both inotropes and vasodilators in post-CPB period.

Beta-1 blocker improves survival of septic rats through preservation of gut barrier function.

OBJECTIVE: Since recent study demonstrated beneficial effects of ß-adrenergic blocker in sepsis, we tested the hypothesis that infusion of selective ß1-blocker, esmolol, improves outcome in sepsis by modulating inflammatory responses and gut barrier function. DESIGN: Prospective randomized animal study. SETTING: University research laboratory. SUBJECTS: Male Wistar rats. INTERVENTIONS: To assess the effects of esmolol infusion on survival time, 19 animals that underwent cecal ligation and perforation were randomized into control (n = 9) or esmolol (n = 10) groups, the latter of which received esmolol infusion (15 mg/kg/h) throughout the study period. In an additional 20 animals, levels of tumor necrosis factor-α (TNF-α) in both plasma and intraperitoneal fluid were measured, and mesenteric lymph nodes (MLNs) and ileum were excised for evaluation of bacterial translocation and mucosal injury at the 18-h study period. MEASUREMENTS AND RESULTS: Mean survival time in the esmolol group was significantly longer compared with the control group (69.5 ± 26.8 versus 28.6 ± 11.0 h). Plasma TNF-α was not detectable in either group, while intraperitoneal fluid TNF-α level was elevated in the control group but significantly depressed in the esmolol group (16.8 ± 10.7 versus 5.4 ± 7.1 pg/ml, P < 0.05). Simultaneously, the Escherichia coli positive rate of MLNs was higher (100% versus 44%, P < 0.05) and the gut mucosal injury score was elevated (4.1 ± 0.6 versus 2.8 ± 0.6, P < 0.01) in the control compared with the esmolol group. CONCLUSIONS: Beta-1 blocker therapy improves outcome in sepsis possibly through modulation of gut mucosal integrity and local inflammatory response.

Life-threatening hemothorax resulting from right brachiocephalic vein perforation during right internal jugular vein catheterization.

We present a life-threatening case of hemothorax resulting from right brachiocephalic vein perforation during right internal jugular vein catheterization. We considered that the guidewire had punctured the right brachiocephalic vein extraluminally and the catheter inserted over the guidewire had enlarged the size of the perforation. Despite the use of proper technique, an angle-tip guidewire may perforate the venous wall. Therefore, when there is negative aspiration after central venous catheterization, it is important to perform an emergency chest radiograph before proceeding with surgery; it is also important not to use an angle-tip guidewire.

[Case of an accidental total spinal anesthesia caused by 1% ropivacaine].

A case of accidental total spinal anesthesia was presented. A 47-year-old woman was scheduled for a total abdominal hysterectomy. An epidural catheter was inserted at the L1-2 interspace and 10 ml of 1% ropivacaine was injected. Following surgery, the patient did not regain consciousness and we confirmed total spinal anesthesia because of the cerebrospinal fluid leak through the epidural catheter. Therefore propofol was administered again until the recovery of sufficient spontaneous breathing confirmed approximately 3 hours following administration of ropivacaine, and patient was extubated. No neurologic deficits could be detected.

Performance of noninvasive partial CO2 rebreathing cardiac output and continuous thermodilution cardiac output in patients undergoing aortic reconstruction surgery.

BACKGROUND: In the partial CO(2) rebreathing method, monitored changes in CO(2) elimination and end-tidal CO(2) in response to a brief rebreathing period are used to estimate cardiac output. However, dynamic changes in CO(2) production during ischemia and reperfusion may affect the accuracy of these estimates. This study was designed to compare measurements of cardiac output as produced by the partial CO(2) rebreathing (NICO), bolus (BCO), and continuous thermodilution (CCO) methods of monitoring cardiac output. METHODS: Cardiac output was continuously monitored using both NICO and CCO in 28 patients undergoing aortic reconstruction. BCO measurements were taken at the following intervals when hemodynamic stability was achieved: (1) after anesthetic induction; (2) during aortic cross-clamp; (3) at reperfusion of the iliac artery; and, (4) during peritoneal closure. RESULTS: The bias and precision (1 SD) derived from all the measurements between NICO and BCO was -0.58 +/- 0.9 l/min, whereas for CCO and BCO it was 0.38 +/- 1.17 l/min. The bias between NICO and BCO was small after anesthetic induction and during cross-clamp, but increased following reperfusion. The bias between CCO and BCO was relatively small until reperfusion but increased significantly at peritoneal closure. CONCLUSIONS: Results indicate that in aortic reconstruction surgery the performance of NICO monitoring is comparable with that of CCO; however, the direction of bias in these continuous measurement devices is the opposite.