Perioperative management of patients with atrial fibrillation receiving anticoagulant therapy.

The number of patients with atrial fibrillation (AF) and the number of patients indicated for anticoagulant therapy have been increasing because AF would affect patient survival due to thromboembolism. Once AF develops, following the disappearance of pulsation, the circumstances within the atrium become prothrombotic and thrombus formation within the left atrium occurs in patients with AF. In recent years, not only warfarin but also new oral anticoagulants were introduced clinically and have become used as oral anticoagulants. In the perioperative period, the risk of major hemorrhage needs to be reduced. On the other hand, the suspension of anticoagulant therapy and neutralization of anticoagulant effects elevate the risk of thrombosis. The perioperative management of patients receiving anticoagulant therapy is different from that of scheduled surgery and emergency surgery. In addition, knowledge of the characteristics of each oral anticoagulant is required at drug cessation and resumption. Unlike warfarin, which has been used in the past five decades, direct oral anticoagulants (DOACs) do not have sensitive indicators such as prothrombin time-international normalized ratio. To avoid major hemorrhages and thromboembolism, quantitative assays can be implemented for DOAC monitoring and for reversal therapies in perioperative settings.

[Complications of Epidural Block and Nerve Root Block].

The two major complications clinicians should pay attention to when providing regional anesthesia or nerve block treatment are infection and hematoma. While epidural block is a commonly employed treat- ment method, its complications including epidural abscess and hematoma may require surgical interven- tion to control, and clinicians should perform such blocks with meticulous care. Because early diagnosis and appropriate treatment greatly affect the prognosis from epidural abscess or hematoma, clinicians must have sufficient knowledge of these complications. Knowledge in characteristic symptoms of and treat- ments for pneumocephalus and intracranial hypoten- sion is also required. As, in case of nerve root blocks, different complications may arise depending on which nerve root is treated, clinicians must also have knowl- edge of both the important points to keep in mind and potential complications for each of the cervical, thoracic and lumbar regions.

[With the Characteristics of Chronic Pain Patients, Can the Therapeutic Effect of Antidepressant Duloxetine be Predicted?].

BACKGROUND: Duloxetine, an antidepressant, is used for treatment of pain, but the factors related to its effectiveness are not well known, and therefore we have performed a retrospective study. METHODS: Over a 22-month period from June 2012 patients with pain lasting for 3 months or more, with an NRS of 4 or higher, and given duloxetine within 3 months from their first diagnosis, were extracted from the medical records. These patients were compared and studied regarding their scores of the HADS (hos- pital anxiety and depression scale) at the time of first visit, duration of the disease, type of patient, and treat- ment effect after 1 month. RESULTS: The subjects were 61 patients, and they were categorized based on the presence of anxiety, the presence of dysphoria whether from organic or inor- ganic condition, and the duration of the disease, and no significant difference in the effectiveness of duloxetine was found. CONCLUSIONS: Duloxetine had an overall effectiveness of 50.8%, regardless of the presence of anxiety or depression, the duration of the disease and the type of diseases.

Changes in circadian rhythm for mRNA expression of melatonin 1A and 1B receptors in the hypothalamus under a neuropathic pain-like state.

Several clinical reports on neuropathic pain of various etiologies have shown that it significantly interferes with sleep. Inadequate sleep due to neuropathic pain may contribute to the stressful negative consequences of living with pain. It is generally recognized that melatonin (MT) system in the hypothalmus is crusial for circadian rhythm and sleep-wake transition. However, little, if any, is known about whether neuropathic pain could affect the MT system associated with sleep disturbance. In this study, we investigated the possible changes in circadian rhythm for the expression of MT receptors, especially MT1A and MT1B receptors, in the hypothalamus of mice with sciatic nerve ligation. The samples for real-time RT-PCR assay were prepared at 8:00, 14:00, 20:00, and 2:00 on day 7 after sciatic nerve ligation or sham operation. The mRNA expression of MT1A and MT1B receptors at 2:00 in sciatic nerve-ligated mice, which exhibited thermal hyperalgesia along with an increase in wakefulness and a decrease in nonrapid eye movement sleep, was significantly greater than those in sham-operated mice, whereas the levels of both MT1A and MT1B receptors at 8:00 in sciatic nerve-ligated mice were significantly lower than those in sham-operated mice. These findings suggest that neuropathic pain-like stimuli lead to sleep disturbance in parallel with changes in circadian rhythm for mRNA expression of MT 1A and 1B receptors in the hypothalamus of mice.

[A case of intraoperative cardiac arrest in a patient with mitochondrial encephalomyopathy undergoing lung resection].

We report a case of intraoperative cardiac arrest in a patient with mitochodorial encephalomyopathy undergoing pulmonary wedge resection. The patient is a 50-year-old female who had been diagnosed as progressive external ophthalmoplegia at the age of 44 and underwent resection of mediastinal tumor 11 months before without major events. The patient was found to have lung cancer in the left lung and scheduled for wedge resection. Induction and maintenance of anesthesia using remifentanil and propofol infusion with rocuronium were uneventful until traction and resection of the left bronci when profound hypotension with systolic arterial pressure of 20 mmHg and sinus bradycardia occurred. The rhythm deteriorated to ventricular fibrillation which was refractory to pharmacological therapy including adrenaline (a total dose of 5 mg), lidocaine and nifekalant, and DC shock. The patient was finally stabilized after intraaortic balloon pumping and percutaneous cardiopulmonary support. Although the diagnosis of Takotsubo myopathy was made by echocardiography after surgery, the cause of cardiac arrest was not known.

Neuropathies Following an Ultrasound-Guided Axillary Brachial Plexus Block.

Purpose: Ultrasound-guided brachial plexus block (UGBPB) has interscalene, supraclavicular, infraclavicular, and axillary approaches. The axillary block is considered to be the safest and with fewer adverse events compared to the interscalene (eg, phrenic nerve block, spinal cord or vertebral artery puncture) and supraclavicular (eg, pneumothorax). However, with regard to postoperative neurological symptoms (PONS), it is controversial whether its incidence after an axillary block was higher than that after non-axillary approaches". In this study, we investigated whether the incidence of a neuropathy after an axillary block was higher than that after non-axillary approaches. Patients and Methods: This was a single-center, retrospective cohort study. All UGBPBs were performed under general anesthesia between January 2014 and March 2020. The outcomes included the overall incidence of PONS and neuropathies for axillary and non-axillary approaches. The etiology, symptoms, and outcomes of patients were investigated. Results: Of the 992 patients, 143 (14%) and 849 (86%) were subjected to axillary and non-axillary approaches, respectively. Among 19 cases (19.2:1000; 95% confidence interval [CI], 18.2-20.1) of PONS, four (4.0:1000; 95% CI, 3.8-4.2) were neuropathies attributed to the UGBPB, three (21.0:1000; 95% CI, 18.1-23.8) to the axillary and one (2.8:1000; 95% CI, 2.6-3.1) to non-axillary approaches. The incidence of neuropathies after an axillary block was significantly higher than that after non-axillary approaches (P = 0.005). Conclusion: The incidence of neuropathies after US-guided axillary block under general anesthesia was significantly higher than that after non-axillary approaches.

Lateral Femoral Cutaneous Nerve Block for Postoperative Pain Control After Total Hip Arthroplasty Using the Direct Anterior Approach: A Single-blinded Randomized Control Trial.

Background: Total hip arthroplasty (THA) employing the direct anterior approach (DAA) is increasingly performed as a less invasive procedure with faster recovery than other approaches. Unlike other approaches, the skin incision is made on the lateral thigh, distal to the inguinal ligament. However, the effectiveness of ultrasound-guided lateral femoral cutaneous nerve (LFCN) block for postoperative analgesia after THA using DAA has not been investigated.We hypothesized that ultrasound-guided LFCN block using DAA would reduce postoperative pain after THA. Methods: A prospective, randomized, observer-blinded controlled trial was conducted. The 92 patients included were divided into two groups: those who received only femoral nerve block (FNB group) and those who received femoral nerve block and LFCN block with 10mL of 0.25% levobupivacaine (FNB + LFCNB group). Both groups received intravenous patient-controlled analgesia (fentanyl) postoperatively. A numerical rating scale was used to quantify pain at 3 and 48 h postoperatively. Results: There was no significant difference in pain at rest and during movement between the FNB and FNB + LFCNB groups (at rest: Z = -1.6814, p=0.0927; during on movement: Z = -0.9677, p=0.9487). There was also no significant difference in pain severity at rest and during movement between the FNB and FNB + LFCNB groups postoperatively. Conclusions: LFCNB did not improve postoperative pain relief in patients undergoing THA with DAA.

Unusual severe hypoxemia due to unilateral pulmonary edema after conventional cardiopulmonary bypass salvaged by veno-venous extracorporeal membrane oxygenation: a case report.

BACKGROUND: We report a case in which veno-venous extracorporeal membrane oxygenation (V-V ECMO) saved the life of a patient who developed severe hypoxemia due to unusual unilateral pulmonary edema (UPE) after cardiopulmonary bypass (CPB). CASE PRESENTATION: A 69-year-old man underwent aortic valve replacement and coronary artery bypass grafting. Following uneventful weaning off CPB, he developed severe hypoxemia. The ratio of arterial oxygen tension to inspired oxygen fraction (PaO2/FiO2) decreased from 301 mmHg 5 min after CPB to 42 mmHg 90 min after CPB. A chest X-ray revealed right-sided UPE. Immediately established V-V ECMO increased PaO2/FiO2 to 170 mmHg. Re-expansion pulmonary edema (REPE) was likely, as the right lung remained collapsed during CPB following the accidental opening of the right chest cavity during graft harvesting. CONCLUSIONS: V-V ECMO was effective in improving oxygenation and saving the life of a patient who had fallen into unilateral REPE unusually developing after conventional CPB.

Postoperative Heart Failure with Preserved Ejection Fraction Induced by Flumazenil Administered for Remimazolam Antagonism.

Remimazolam is an ultrashort-acting benzodiazepine intravenous anesthetic characterized by rapid awakening after anesthesia. However, the method for administering remimazolam in clinical practice remains unclear. Here, we report a case of postoperative heart failure with preserved ejection fraction (HFpEF) after antagonizing remimazolam with flumazenil. An 82-year-old woman was scheduled to undergo lumbar laminectomy for lumbar spinal canal stenosis. Preoperative echocardiography revealed normal left ventricular systolic function, left atrial enlargement, and impaired left ventricular diastolic function. General anesthesia was induced with 10 mg/kg/h remimazolam and maintained with 0.8 mg/kg/h remimazolam intraoperatively. Before extubation, a total of 1.0 mg of flumazenil was administered. After extubation, the patient developed pulmonary edema due to HFpEF. When remimazolam is administered in elderly patients with cardiac dysfunction, the maintenance dose should be customized according to the patient's general condition to minimize the dosage of flumazenil.

[Successful anesthetic management of a postpartum patient with amniotic fluid embolism].

We report a case of amniotic fluid embolism (AFE) after cesarean section (C/S). A 35-year-old primigravida with placenta previa and myoma underwent C/S because of nonreassuring fetal status caused by medical induction of labor. C/S was performed smoothly under general anesthesia and the baby had no problems. Immediately after the end of C/S, she went into sudden cardiovascular collapse and massive postpartum hemorrhage (PPH) became apparent. The mechanical ventilation with 100% oxygen was continued. Cardiovascular stabilization was attained with immediate administration of noradrenaline and blood transfusion. As her clinical course indicated coagulopathy due to disseminated intravascular coagulation (DIC), we gave transfusion of fresh frozen plasma and red cell concentrate before the diagnosis of DIC was established by laboratory tests. Since we thought that manual pressure and uterotonics were not adequate to stop PPH, we performed uterine artery embolization additionally. The PPH with DIC was stopped by these measures seven hours after C/S. The patient and her baby left the hospital with no complications. AFE is a rare and often fatal obstetric condition, characterized by sudden cardiovascular collapse, and massive bleeding with DIC. The prompt awareness and initiation of appropriate measures are mandatory for patient's survival.

Sex-Specific Impact of Pain Severity, Insomnia, and Psychosocial Factors on Disability due to Spinal Degenerative Disease.

Purpose: Pain experience due to spinal degenerative disease decreases activity of daily living and quality of life. The present cross-sectional study was aimed at examining the sex-specific impact of pain severity, psychosocial factors, and insomnia on the disability due to chronic pain arising from spinal degenerative disease. Methods: In total, 111 outpatients with chronic spinal degenerative on initial diagnosis were analyzed. The definition of chronic spinal degenerative disease was (1) pain duration ≥3 months, (2) findings of nerve root compression on neurological examination and imaging, and (3) localized neck or lower back pain (not widespread, upper or lower limb pain). We used Numerical Rating Scale (NRS), Pain Disability Assessment Scale (PDAS), Hospital Anxiety and Depression Scale (HADS), Pain Catastrophizing Scale (PCS), and Athens Insomnia Scale (AIS) to assess patients. Univariate regression analysis was performed to investigate whether sex influences the PDAS score, and sex-stratified multivariate regression analysis was conducted to identify the variables associated with the PDAS score. Results: Sex was identified as a predictor of the PDAS score (standardized coefficient (ß) = 0.28; 95% confidence interval (CI), 0.10-0.46; p=0.003). In men, the AIS score was associated with PDAS (ß = 0.36, 95% CI 0.09-0.63). Age (ß = 0.31, 95% CI 0.06-0.55) and NRS (ß = 0.40, 95% CI 0.14-0.67) were associated with PDAS in women. HADS-A, HADS-D, and PCS were not associated with PDAS in both sexes. Conclusion: Insomnia was associated with disability in men, whereas aging and pain severity were associated with disability in women. Catastrophic thinking was not associated with disability in both sexes.

Fixation of intracapsular fracture of the femoral neck using combined peripheral nerve blocks and transthoracic echocardiography in a patient with severe obstructive hypertrophic cardiomyopathy: a case report.

BACKGROUND: Hypertrophic obstructive cardiomyopathy (HOCM) is a type of hypertrophic cardiomyopathy associated with left ventricular outflow tract stenosis. The increased pressure gradients across the left ventricular outflow tract in patients with HOCM could lead to circulatory collapse. We describe our experience with perioperative management under femoral nerve block (FNB), lateral femoral cutaneous nerve block (LFCNB), and transthoracic echocardiography (TTE) monitoring during open reduction and internal fixation of a femoral neck fracture in a patient with severe HOCM. CASE PRESENTATION: A 72-year-old man, who was indicated to undergo open reduction and internal fixation of an intracapsular femoral neck fracture, had a history of treatment for hypertension and HOCM. He had heart failure for 4 years and was hospitalized several times. He was resuscitated after ventricular fibrillation and received an implantable cardioverter-defibrillator at that time. He also had severe physical limitations (New York Heart Association class III). We selected FNB and LFCNB as the methods for anesthesia and injected 0.25% levobupivacaine (20 mL) around the femoral nerve and 0.25% levobupivacaine (10 mL) into the lateral femoral nerve region. He underwent TTE during the perioperative period, which enabled us to perform hemodynamic and morphological evaluations of the heart. The intraoperative TTE findings remained stable from before the induction of anesthesia to the patient's exit from the operating room. Postoperatively, his hemodynamic parameters continued to remain stable. CONCLUSIONS: In this case, FNB and LFCNB contributed to hemodynamic stability during non-cardiac surgery. Additionally, TTE was useful for the perioperative evaluation of cardiac hemodynamics and morphology in our patient with severe HOCM.

Respiratory failure caused by impending tension pneumothorax after extrapleural pneumonectomy: a case report.

BACKGROUND: Cardiac herniation is a serious postoperative complication of extrapleural pneumonectomy (EPP) and is reportedly preventable by reducing the suction pressure of the chest drain. CASE PRESENTATION: We describe a patient in whom respiratory failure, which was caused by impending tension pneumothorax after EPP, was successfully treated via normal suction pressure of the chest drain. A lower suction pressure (- 7 cmH2O) was chosen as an alternative to the setting typically used for postoperative drainage (- 15 cmH2O). As a result, the wound in the chest wall functioned as an antireflux check valve, leading to the development of impending tension pneumothorax. CONCLUSIONS: Impending tension pneumothorax presents with an abnormal elevation of intrapleural pressure on the affected side. This phenomenon can be effectively treated by increasing the suction pressure in the chest drain.

Possible involvement of activated locus coeruleus-noradrenergic neurons in pain-related sleep disorders.

The locus coeruleus (LC) is a noradrenergic brainstem structure that is considered to play a role in promoting arousal. To further clarify the role of LC noradrenergic neurons, we performed an optogenetic assay by injecting AAV-channelrhodopsin-2 (ChR2) into the LC of cre-tyrosine hydrolase (TH) mice. We found here that the specific activation of LC noradrenergic neurons produced a significant increase in wakefulness and a significant decrease in non-rapid eye movement (NREM) sleep during photostimulation. On the other hand, neuropathic pain is believed to significantly interfere with sleep, and inadequate sleep may contribute to the stressful negative consequences of living with pain. In the present study, sciatic nerve ligation, which produced significant thermal hyperalgesia, significantly increased the levels of noradrenaline released in the prefrontal cortex (PFC) by the weak electrical stimulation of neurons in the LC. Under these conditions, the systemic administration of adrenaline α and ß inhibitor cocktail at 7 days after sciatic nerve ligation restored the increased wakefulness and decreased NREM sleep to normal levels. These results suggest that neuropathic pain may accelerate neurons in the LC, and its overactivation may be, at least in part, associated with sleep disturbance under neuropathic pain.