Assessing different brain oxygenation components in elderly patients under propofol or sevoflurane anesthesia: A randomized controlled study.

STUDY OBJECTIVE: Elderly patients undergoing pathophysiological changes necessitate clinical tools for cerebral monitoring. This prospective randomized controlled study aimed to explore how cerebral monitoring using Δo2Hbi, ΔHHbi, and ΔcHbi manifests in elderly patients under either propofol or sevoflurane anesthesia. DESIGN: Single-center, prospective, randomization. SETTING: A single tertiary hospital (Eunpyeong St. Mary's Hospital, College of Medicine, The Catholic University of Korea). PATIENTS: Enrolled 100 patients scheduled for urologic surgery under general anesthesia. Inclusion criteria were (a) age 70-80 years, (b) American Society of Anesthesiologists (ASA) physical status I-II. INTERVENTION: Patients were double-blind randomized to receive propofol-based or sevoflurane anesthesia. Cerebral oximetry-related parameters were measured at 5, 10, 15, 20, and 30 min in a setting devoid of surgery-related factors. MEASUREMENTS: The primary outcome focused on the Δo2Hbi pattern in the left and right sides within the propofol and sevoflurane groups. MAIN RESULTS: We analyzed 100 patients, 50 patients in each group. In the propofol group, the left Δo2Hbi decreased from 1.4 (3.7) at 5 min to -0.1 (1.8) at 30 min (P < 0.0001), and the right Δo2Hbi decreased from 2.9 (4.2) at 5 min to -0.06 (2.3) at 30 min (P < 0.0001). In the sevoflurane group, the left Δo2Hbi decreased from 1.1 (3.4) at 5 min to -1.4 (4.4) at 30 min (P < 0.0001), and the right Δo2Hbi decreased from 2.0 (3.2) at 5 min to -1.2 (3.9) at 30 min (P < 0.0001). There were no significant differences between the two groups. ΔHHbi did not exhibit significant changes after an initial decrease at 5 min and showed no significant differences between the two groups. CONCLUSIONS: In cerebral oximetry, Δo2Hbi and ΔHHbi could emerge as a valuable approach for discerning changes in the underlying baseline status of the brain in elderly patients during anesthesia.

A Quantitative Measure of Pain with Current Perception Threshold, Pain Equivalent Current, and Quantified Pain Degree: A Retrospective Study.

Background: As a subjective sensation, pain is difficult to evaluate objectively. The assessment of pain degree is largely dependent on subjective methods such as the numeric rating scale (NRS). The PainVisionTM system has recently been introduced as an objective pain degree measurement tool. The purpose of this study was to analyze correlations between the NRS and the current perception threshold (CPT), pain equivalent current (PEC), and quantified pain degree (QPD). Methods: Medical records of 398 subjects who visited the pain clinic in a university hospital from March 2017 to February 2019 were retrospectively reviewed. To evaluate the pain degree, NRS, CPT, PEC, and QPD were measured. Subjects were categorized into two groups: the Pain group (n = 355) and the No-pain group (n = 43). Results: The NRS showed a negative correlation with CPT (R = -0.10, p = 0.054) and a positive correlation with QPD (R = 0.13, p = 0.008). Among various diseases, only spinal disease patients showed a negative correlation between CPT and NRS (R = -0.22, p = 0.003). Additionally, there were significant differences in CPT and QPD between the Pain and No-pain groups (p = 0.005 and p = 0.002, respectively). Conclusions: CPT and QPD measured using the PainVisionTM system could be used to estimate pain intensity and the presence of pain. These parameters would be considered useful for predicting pain itself and its intensity.

Prediction of hypotension during the alveolar recruitment maneuver in spine surgery: a prospective observational study.

BACKGROUND: Atelectasis can occur in many clinical practices. One way to prevent this complication is through the alveolar recruitment maneuver (ARM). However, hemodynamic compromise can accompany ARM. This study aims to predict ARM-induced hypotension using a non-invasive method. METHODS: 94 American Society of Anesthesiologists physical status I-II patients aged 19 to 75 with scheduled spinal surgery were enrolled. After anesthesia, we performed a stepwise ARM. Data on perfusion index, mean arterial pressure, heart rate, pleth variability index, cardiac index, and stroke volume variation was collected before induction of anesthesia (T0), just before ARM (T1), at the start of ARM (T2), 0.5 min (T3), 1 min (T4), 1.5 min (T5, end of ARM), and 2 min after the beginning of ARM (T6). Hypotension was defined as when the mean arterial pressure at T5 decreased by 20% or more compared to the baseline. The primary endpoint is that the perfusion index measuring before induction of anesthesia, which reflects the patients' own vascular tone, was correlated with hypotension during ARM. RESULTS: Seventy-five patients (79.8%) patients developed hypotension during ARM. The pre-induction persufion index (Pi) (95% confidence interval) was 1.7(1.4-3.1) in the non-hypotension group and 3.4(2.4-3.9) in the hypotension group. (p < 0.004) The hypotension group showed considerably higher Pi than the non-hypotension group before induction. The decrease of Pi (%) [IQR] in the non-hypotensive group (52.8% [33.3-74.7]) was more significant than in the hypotensive group. (36% [17.6-53.7]) (p < 0.05) The area under the receiver operating characteristic curve of Pi for predicting hypotension during ARM was 0.718 (95% CI 0.615-0.806; p = 0.004), and the threshold value of the Pi was 2.4. CONCLUSION: A higher perfusion index value measuring before induction of anesthesia can be used to predict the development of hypotension during ARM. Prophylactic management of the following hypotension during ARM could be considered in high baseline Pi patients.

Transient asystole during balloon dilation of the Eustachian tube: A case report.

RATIONALE: Neurally mediated reflexes can induce cardiac arrest during head and neck surgery through mechanisms including direct vagal stimulation, trigeminocardiac reflex, and baroreceptor reflex. Balloon dilation of the Eustachian tube (BDET) is a safe procedure without serious complications, including cardiac arrest. PATIENT CONCERNS: Transient asystole developed during BDET under general anesthesia in a 33-year-old woman as soon as the balloon in the Eustachian tube (ET) was inflated. DIAGNOSES: Monitoring records were reviewed. The asystolic period was recorded on the patient monitor as an event, which we recalled and printed. The asystole lasted for 13 seconds. INTERVENTIONS: The patient recovered sinus rhythm spontaneously after the balloon was deflated before resuscitation. The BDET was successfully performed after prophylaxis with vagolytic drugs. OUTCOMES: The patient recovered uneventfully after anesthesia. LESSONS: BDET, previously known to be a relatively safe procedure, induces asystole via balloon dilation. It is thought to be a neurally mediated vagal reflex, and both anesthesiologists and otologic physicians should pay proper attention to monitoring during the procedure.

The Perfusion Index of the Ear as a Predictor of Hypotension Following the Induction of Anesthesia in Patients with Hypertension: A Prospective Observational Study.

Patients with hypertension develop hemodynamic instability more frequently during anesthesia-particularly post-induction. Therefore, different monitoring methods may be required in patients with hypertension. Perfusion index-the ratio of the pulsatile blood flow to the non-pulsatile static blood flow in a patient's peripheral tissues, such as the fingers or ears-can show the hemodynamic status of the patient in a non-invasive way. Among the sites used for measuring the perfusion index, it is assumed that the ear is more reliable than the finger for hemodynamic monitoring, because proximity to the brain ensures appropriate perfusion. We hypothesized that the low value of preoperative ear PI could be a predictor of post-induction hypotension in patients with hypertension. Thirty patients with hypertension were enrolled. The perfusion index and pleth variability index were measured using the ear, finger, and blood pressure, and heart rate was recorded to monitor hypotension. After insertion of the supraglottic airway, 20 patients developed post-induction hypotension. Those who developed hypotension showed a significantly lower preoperative perfusion index of the ear. The preoperative perfusion index of the ear could predict post-induction hypotension in patients with hypertension.

The i-gel supraglottic airway device improves airway management during endobronchial ablative therapy under general anesthesia: a case report.

Endobronchial ablative therapy (EAT) in patients with preexisting obstructive airway disease can cause hypoxemia because bronchoscope insertion interferes with ventilation and a low fraction of inspired oxygen (FiO2) is essential to avoid airway fire. A man in his early 50s with moderately severe obstructive airway disease was scheduled for EAT for treatment of tracheal papillomatosis. Ventilation and oxygenation would have been difficult because of narrowing of the endotracheal tube by bronchoscopic insertion and a low FiO2; therefore, an i-gel supraglottic airway device with a larger inner diameter was inserted. All visible intratracheal papillomas were ablated by a potassium titanyl phosphate laser through the bronchoscopic port that passed through the lumen of the i-gel at an FiO2 of 0.3. During anesthesia for EAT, the i-gel supraglottic airway device provided a wider lumen for ventilation. We were thus able to provide stable ventilation at an FiO2 of 0.3 during EAT in this patient with obstructive airway disease, avoiding airway fire and hypoxemia.

Association between Successful Palpation of the Cricothyroid Membrane and the 3-3-2 Rule for Predicting Difficult Airway in Female Patients Undergoing Non-Neck Surgery: A Prospective Observational Cohort Study.

Background: Prediction of difficult airway is important for airway management in patients undergoing surgery. The assessment of airway structures and establishment of protective airway strategies are essential to improve patient safety. However, the association between successful palpation of the cricothyroid membrane and airway predictions has not been fully elucidated in patients undergoing surgery. We investigated this in female patients undergoing non-neck surgery. Methods: A total of 68 female patients were enrolled in this prospective observational cohort study between January 2021 and June 2021 at Eunpyeong St. Mary's Hospital, College of Medicine, Catholic University of Korea, Seoul, Republic of Korea. Exclusion criteria were male patients and those with neck pathology or neck surgery. The assessment of difficult airway was performed before the induction of anesthesia and was defined by one of the following conditions: inter-incisor distance < 3 fingerbreadths, hyoid-to-mental distance < 3 fingerbreadths, and thyroid-to-hyoid distance < 2 fingerbreadths (the "3-3-2 rule"). The accuracy of palpable identification of the cricothyroid membrane was confirmed by ultrasonography (US). The patients were divided into the non-difficult airway (NDA) group (n = 30) and the difficult airway (DA) group (n = 30). Results: The two groups were comparable in terms of age, but the DA group had higher body mass index (BMI). In airway assessment, 9 patients showed inter-incisor distance < 3 fingerbreadths, 3 patients showed hyoid-to-mental distance < 3 fingerbreadths, and 24 patients showed thyroid-to-hyoid distance < 2 fingerbreadths in the DA group. The rate of successful palpation of the cricothyroid membrane was higher in the patients without than in those with difficult airway variables. Conclusions: Patients with a positive 3-3-2 rule showed a poor palpability of cricothyroid membrane.

Delayed-onset malignant hyperthermia in the postanesthetic care unit: a case report.

Malignant hyperthermia (MH) is a potentially fatal hypermetabolic syndrome that occurs when susceptible individuals are exposed to triggering agents. Variability in the order and time of occurrence of symptoms often makes clinical diagnosis difficult. A late diagnosis or misdiagnosis of delayed-onset MH may lead to fatal complications. We herein report a case of delayed-onset MH in the postoperative recovery room. A 77-year-old man awoke from anesthesia and was transferred to the recovery room. Ten minutes after his arrival, his mental status became stuporous and he developed masseter muscle rigidity, hyperventilation, and a body temperature of 39.8°C. The patient was suspected to have MH, and 60 mg of dantrolene sodium (1 mg/kg) was administered via intravenous drip with symptomatic treatment. Within 10 minutes of dantrolene administration, the patient's clinical signs subsided. This case report demonstrates that rapid diagnosis and treatment are crucial to ensure a good prognosis for patients with MH. A high level of suspicion based on clinical symptoms and early administration of therapeutic drugs such as dantrolene will also improve the clinical course. Therefore, suspicion and prompt diagnosis are absolutely essential. This case report emphasizes the importance of continuous education in the diagnosis and treatment of MH.

Massive venous air embolism with bleeding caused by femoral vein injury during total hip arthroplasty: A case report.

INTRODUCTION: Venous air embolism (VAE) from vascular injuries, is of rare occurrence but can result in catastrophic complications during total hip arthroplasty (THA). Early recognition and prompt management of vascular injury are required to avoid severe complications. Especially, bleeding is generally associated with profound hypotension in venous injury. We report an unusual complication of venous air embolism induced by femoral vein rupture during THA. PATIENT CONCERNS: A 54-year-old male patient with a history of old left acetabular fracture was scheduled for THA. We experienced massive bleeding and VAE induced by femoral vein rupture during total hip arthroplasty. The BP suddenly dropped from 100/70 mm Hg to 80/50 mm Hg with massive bleeding. ETCO2 and SaO2 decreased profoundly. DIAGNOSIS: The VAE was diagnosed by the change in end- tidal CO2 (ETCO2) and change of vital signs, so we performed ABGA and inserted TEE for confirmination. INTERVENTIONS: For treatment, patient was managed by oxygen therapy, inotropics, vasopressor, transfusion and surgical repair. OUTCOMES: Upon consulting with a cardiologist, the patient was extubated the next day and was transferred to the general ward and recovered without serious complications. He stayed for 17 days until finally discharged without complications. CONCLUSION: Preoperative vascular imaging may be recommended in the revisional case of THA or in patients with the history of hip trauma. The monitoring of ETCO2 and TEE might be helpful to recognize VAE earlier and therefore to avoid catastrophic complications through adequate treatment.

Preventing deoxygenation with high flow nasal cannula oxygen during induction of general anesthesia for rigid bronchoscopy: Two case reports.

RATIONALE: Rigid bronchoscopy under general anesthesia enables performing diagnostic and/or therapeutic procedures in the tracheobronchial tree. As most patients undergoing rigid bronchoscopy have moderate to severe respiratory disease or central airway obstruction, the operators often face the risk of hypoxemia when inserting the rigid bronchoscope into the patients' airway. Applying high flow nasal cannula (HFNC) oxygen therapy before the insertion of the bronchoscope allows to maintain high fractional inspired oxygen (FiO2) and thus leading to maximizing apnea time before desaturation. PATIENT CONCERNS AND DIAGNOSIS: Case 1: A 70-year-old female patient was diagnosed with lung cancer in the left lower lobe and a tracheal mass of about 2.6 cm * 0.8 cm in size.Case 2: A male patient, 77 years old, 55.7 kg and 157.3 cm in height, had been diagnosed with chronic obstructive pulmonary disease, and was scheduled for the bronchoscopic volume reduction surgery upon exacerbation of his symptoms of dyspnea and cough with sputum. INTERVENTIONS: Preoxygenation was performed with HFNC (Fisher&Paykel Optiflow Thrive, New Zealand) for 3 minutes before the administration of anesthetic medications. The oxygen flow was set at 50 L/min and the FiO2 at 1.0. SpO2 increased to 100%. OUTCOMES: The HFNC oxygen has shown its effectiveness in safely maintaining the patients' SpO2 during the prolonged apneic period of inserting bronchoscope. LESSONS: HFNC oxygen is an effective tool in oxygenating the patients during the induction of rigid bronchoscopy, and that it may be a superior alternative to the conventional method of preoxygenation.

Successful airway management with combined use of McGrath® MAC video laryngoscope and fiberoptic bronchoscope in a severe obese patient with huge goiter -a case report.

Huge goitor can lead to tracheal compression and hence difficulty in intubation. This is compounded by severe obesity. Failed tracheal intubation in difficult intubation is a serious event that may lead to increased patient morbidity and mortality. Current intubation rescue techniques and combination of different rescue techniques may increase the success rate of difficult intubation. In a 47-year-old female patient, with severe obesity and a huge goiter, our attempts at intubation using direct laryngoscope, video laryngoscope, and awake fiberoptic bronchoscope had failed. We succeeded by applying video laryngoscope to improve visualization of the airway and fiberoptic bronchoscope as a stylet for endotracheal tube.

Hemoptysis during general anesthesia in a diabetic patient with healed tuberculosis: a case report.

Hemoptysis is a common complication of pulmonary tuberculosis. Most of the cases of hemoptysis originate from hypertrophied bronchial arteries. Also, diabetes induces pulmonary vascular abnormalities such as endothelial dysfunction, inflammatory infiltration and pulmonary vascular remodeling. A 27-year-old male, with diabetes and a history of tuberculosis, underwent the procedure of pars plana vitrectomy under general anesthesia. After an uneventful intra-operative period, he had hemoptysis prior to extubation. Emergency fiberoptic bronchscopy showed blood plugs and spotted fresh blood at the right upper lobar bronchus. After successful embolization of the bronchial artery, the patient made a recovery and was discharged without experiencing any complication. Predisposing factors of hemoptysis in this case are presumed to be tuberculosis and diabetes. The bleeding might had been caused by the rupture of a weakened artery within the cavity in the right upper lobe, through expansion of the lung during manual ventilation by positive pressure.

Fatal cardiac thromboembolism in a patient with a pacemaker during ureteroscopic lithotripsy for ureter stone: a case report.

Intracardiac thrombosis is an infrequent and fatal complication in patients with an inserted pacemaker. A patient with an inserted pacemaker scheduled for ureter stone removal experienced cardiac arrest and cardiopulmonary resuscitation under general anesthesia. Echocardiography showed multiple intracardiac thrombi. Preoperative diagnostic workup including echocardiography for the detection of pacemaker lead thrombus, and the need for anticoagulation should be considered in patients with an inserted pacemaker and high-risk factors for thrombosis.

Development of a bead-based multiplex genotyping method for diagnostic characterization of HPV infection.

The accurate genotyping of human papillomavirus (HPV) is clinically important because the oncogenic potential of HPV is dependent on specific genotypes. Here, we described the development of a bead-based multiplex HPV genotyping (MPG) method which is able to detect 20 types of HPV (15 high-risk HPV types 16, 18, 31, 33, 35, 39, 45, 51, 52, 53, 56, 58, 59, 66, 68 and 5 low-risk HPV types 6, 11, 40, 55, 70) and evaluated its accuracy with sequencing. A total of 890 clinical samples were studied. Among these samples, 484 were HPV positive and 406 were HPV negative by consensus primer (PGMY09/11) directed PCR. The genotyping of 484 HPV positive samples was carried out by the bead-based MPG method. The accuracy was 93.5% (95% CI, 91.0-96.0), 80.1% (95% CI, 72.3-87.9) for single and multiple infections, respectively, while a complete type mismatch was observed only in one sample. The MPG method indiscriminately detected dysplasia of several cytological grades including 71.8% (95% CI, 61.5-82.3) of ASCUS (atypical squamous cells of undetermined significance) and more specific for high grade lesions. For women with HSIL (high grade squamous intraepithelial lesion) and SCC diagnosis, 32 women showed a PPV (positive predictive value) of 77.3% (95% CI, 64.8-89.8). Among women >40 years of age, 22 women with histological cervical cancer lesions showed a PPV of 88% (95% CI, 75.3-100). Of the highest risk HPV types including HPV-16, 18 and 31 positive women of the same age groups, 34 women with histological cervical cancer lesions showed a PPV of 77.3% (95% CI, 65.0-89.6). Taken together, the bead-based MPG method could successfully detect high-grade lesions and high-risk HPV types with a high degree of accuracy in clinical samples.

Airway fire injury during rigid bronchoscopy in a patient with a silicon stent -A case report-.

Therapeutic bronchoscopy is widely employed as an effective first-line treatment for patients with central airway obstructions. Airway fires during rigid bronchoscopy are rare, but can have potentially devastating consequences. Pulmonologist and anesthesiologist undertaking this type of procedure should be aware of this serious problem and be familiar with measures to avoid this possibly fatal complication. We report the case of a 24-year-old patient with a silicone stent who experienced an electrocautery-induced airway fire during rigid bronchoscopy.

Integration of gene-expression profiles and pathway analysis in ascending thoracic aortic aneurysms.

BACKGROUND: Despite the increasing incidence of ascending thoracic aortic aneurysms, their pathogenesis and molecular mechanisms remain unknown. The aim of this study was to identify the biological pathways of genes that are expressed differentially in ascending aortic aneurysms. METHODS: Aneurysm wall tissues were obtained from thoracic aortic aneurysms during their repair and normal thoracic aortas from organ transplant patients. The differential expression of genes was analyzed by NimbleGen microarrays. The biological pathways and processes were identified using Kyoto Encyclopedia of Genes and Genome pathway analysis and gene ontology analysis. RESULTS: Among 45,034 genes, 95 were differentially expressed (>two-fold change compared with control). A total of 76 genes were up-regulated and 19 genes were down-regulated in patients with ascending thoracic aneurysm. Analysis of the Kyoto Encyclopedia of Genes and Genomes pathways revealed 26 biologically functional pathways in the following categories: focal adhesion, cell junctions, peroxisome proliferator-activated receptor signaling pathway, extracellular matrix-receptor interaction, T-cell-receptor signaling pathway, B-cell-receptor signaling pathway, and regulation of the actin cytoskeleton. Differentially expressed genes were associated with 123 different gene ontology biological processes: transport, signal transduction, inflammatory response, chemotaxis, and immune response. CONCLUSION: We identified that differentially expressed genes are associated with the pathways that are mainly involved in interactions between cells and the extracellular matrix, and with immune function. The reported data provide useful information on the molecular mechanisms underlying the formation of ascending aortic aneurysms.

Insulin resistance and impaired baroreflex gain during pregnancy.

Pregnancy decreases baroreflex gain, but the underlying mechanism is unclear. Insulin resistance, which has been associated with reduced transport of insulin into the brain, is a consistent feature of many conditions exhibiting impaired baroreflex gain, including pregnancy. Therefore, using conscious pregnant and nonpregnant rabbits, we tested the novel hypothesis that the pregnancy-induced impairment in baroreflex gain is due to insulin resistance and reduced brain insulin. Baroreflex gain was determined by quantifying changes in heart rate in response to stepwise steady-state changes in arterial pressure, secondary to infusion of nitroprusside and phenylephrine. We found that insulin sensitivity and baroreflex gain were strongly correlated in nonpregnant and term pregnant rabbits (r2 = 0.59). The decrease in insulin sensitivity and in baroreflex gain exhibited similar time courses throughout pregnancy, reaching significantly lower levels at 3 wk of gestation and remaining reduced at 4 wk (term is 31 days). Treatment of rabbits with the insulin-sensitizing drug rosiglitazone during pregnancy almost completely normalized baroreflex gain. Finally, pregnancy significantly lowered cerebrospinal fluid insulin concentrations. These data identify insulin resistance as a mechanism underlying pregnancy-induced baroreflex impairment and suggest, for the first time in any condition, that decreased brain insulin concentrations may be the link between reductions in peripheral insulin sensitivity and baroreflex gain.