Accuracy of Catheter Positioning during Left Subclavian Venous Access: A Randomized Comparison between Radiological and Topographical Landmarks.

Left subclavian venous access increases the risk of vascular damage and thrombosis based on the catheter course and location of the catheter tip. We investigated the accuracy of tip positioning with conventional landmarks using transesophageal echocardiography. The carina as a radiological landmark and the right third intercostal space as a topographical landmark were selected for tip positioning within the target zone, defined as 2 cm above and 1 cm below the right atrial junction. A total of 120 participants were randomized into two groups. The catheter insertion depth was determined as 1.5 cm more than the distance between the venous insertion point and the carina via the right first intercostal space in the radiological group, and between the venous insertion point and the right third intercostal space via the right first intercostal space in the topographical group. The determined insertion depth and actual distance to the right atrial junction of the radiological and topographical groups were 19.5 cm and 20.5 cm, and 19.8 cm and 20.4 cm, respectively. Acceptable positioning was more frequent in the topographical group (96.4% vs. 85.7%; p = 0.047). The catheter tip is more accurately positioned in the distal superior vena cava using topographical landmarks than radiological landmarks.

Hemidiaphragmatic Paresis Following Interscalene Brachial Plexus Block With 2-Point Injection Technique.

BACKGROUND: An interscalene brachial plexus block is a commonly conducted nerve block for anesthesia and analgesia in shoulder surgery. Due to its proximity to the targeted nerve, the phrenic nerve, which innervates the diaphragm, is typically inadvertently blocked by ventral spread of the local anesthetic. Although hemidiaphragmatic paresis is tolerable in healthy patients, it would be an irreversible risk to patients with compromised lung reserve. OBJECTIVES: To investigate the effect of interscalene brachial plexus block on hemidiaphragmatic paresis by comparing the conventional local anesthetic volume with a reduced experimental volume at a more specific position using an ultrasound-guided 2-point injection technique. STUDY DESIGN: Prospective, randomized controlled study registered with the Clinical Trial Registry of Korea (https://cris.nih.go.kr/cris/index.jsp. KCT0005575. 04/11/2020). SETTING: This study was conducted at a single hospital affiliated with an academic institution between April and December 2020. METHODS: Patients undergoing brisement manipulation and arthroscopic shoulder surgery were randomized to the experimental (10 mL of ropivacaine 0.5%) and control groups (15 mL of ropivacaine 0.5%). Fifty-two patients who received an interscalene brachial plexus block for anesthesia and analgesia in the shoulder region. The interscalene block was performed using a 2-point injection and  observing the spread pattern of the local anesthetic. The primary outcome was the incidence of hemidiaphragmatic paresis, estimated by the thickening fraction of the diaphragm. The secondary outcomes included oxygen saturation, presence of dyspnea, resting pain score, and handgrip strength score. RESULTS: Thickening fraction was significantly decreased in the control group compared with the experimental group (median [interquartile range], 13.9 [10.0-18.5] versus 28.5 [14.5-38.8], P < 0.001). The incidence of hemidiaphragmatic paresis was significantly higher in the control group than in the experimental group (92.3% versus 53.8%, P = 0.004). Handgrip strength was significantly reduced in the control group compared with the experimental group (P = 0.029). LIMITATIONS: We did not perform a phrenic nerve conduction study, as it is rarely performed in routine clinical operations. We did not formally assess the distance and spatial relationship of the phrenic nerve to the targeted nerve. Outcome variables including pain assessment were limited to the immediate postoperative period. CONCLUSIONS: Reducing the local anesthetic volume by selective injection and observing the spread pattern resulted in a decreased incidence of hemidiaphragmatic paresis and preserved handgrip strength after interscalene block.

Point of care airway ultrasound to select tracheal tube and determine insertion depth in cleft repair surgery.

We aimed to evaluate the efficacy of using airway ultrasonography to select the correct tracheal tube size and insertion depth in pediatric patients who underwent cleft repair surgery as a way to decrease airway complications and adverse events during perioperative periods. Fifty-one patients (age < 28 months) were consecutively divided into conventional (n = 28) and ultrasound (n = 23) groups. Tracheal tube size and insertion depth were determined using the age-based formula and auscultation in the conventional group, whereas using ultrasonographic measurement of subglottic diameter with auscultation and lung ultrasonography in the ultrasound group. We evaluated the initially selected tube size, insertion depth, ventilatory indices, and the incidence of airway complications and adverse events. Tube insertion depth (median [interquartile range]) was significantly greater in the ultrasound group than in the conventional group (13.5 cm [12.5-14.0] vs 13.0 cm [11.8-13.0], P = 0.045). The number of complications and adverse events was significantly higher in the conventional group than in the ultrasound group (32.1% vs 4.3%, P = 0.013). Airway ultrasound application could reduce airway-related complications and adverse events by determining the appropriate tracheal tube size and insertion depth.

Controlling Residual Lithium in High-Nickel (>90 %) Lithium Layered Oxides for Cathodes in Lithium-Ion Batteries.

The rampant generation of lithium hydroxide and carbonate impurities, commonly known as residual lithium, is a practical obstacle to the mass-scale synthesis and handling of high-nickel (>90 %) layered oxides and their use as high-energy-density cathodes for lithium-ion batteries. Herein, we suggest a simple in situ method to control the residual lithium chemistry of a high-nickel lithium layered oxide, Li(Ni0.91 Co0.06 Mn0.03 )O2 (NCM9163), with minimal side effects. Based on thermodynamic considerations of the preferred reactions, we systematically designed a synthesis process that preemptively converts residual Li2 O (the origin of LiOH and Li2 CO3 ) into a more stable compound by injecting reactive SO2 gas. The preformed lithium sulfate thin film significantly suppresses the generation of LiOH and Li2 CO3 during both synthesis and storage, thereby mitigating slurry gelation and gas evolution and improving the cycle stability.

The efficacy of pre-warming on reducing intraprocedural hypothermia in endovascular coiling of cerebral aneurysms.

BACKGROUND: The anesthetic management of patients undergoing endovascular treatment of cerebral aneurysms in the interventional neuroradiology suite can be challenged by hypothermia because of low ambient temperature for operating and maintaining its equipments. We evaluated the efficacy of skin surface warming prior to induction of anesthesia to prevent the decrease in core temperature and reduce the incidence of hypothermia. METHODS: Seventy-two patients were randomized to pre-warmed and control group. The patients in pre-warmed group were warmed 30 minutes before induction with a forced-air warming blanket set at 38°C. Pre-induction tympanic temperature (Tpre) was measured using an infrared tympanic thermometer and core temperature was measured at the esophagus immediately after intubation (T0) and recorded at 20 minutes intervals (T20, T40, T60, T80, T100, and T120). The number of patients who became hypothermic at each time was recorded. RESULTS: Tpre in the control and pre-warmed group were 36.4 ± 0.4°C and 36.6 ± 0.3°C, whereas T0 were 36.5 ± 0.4°C and 36.6 ± 0.2°C. Core temperatures in the pre-warmed group were significantly higher than the control group at T20, T40, T60, T80, T100, and T120 (P < 0.001). Compared to T0, core temperatures at each time were significantly lower in both two groups (P = 0.007 at T20 in pre-warmed group, P < 0.001 at the other times in both groups). The incidence of hypothermia was significantly lower in the pre-warmed group than the control group from T20 to T120 (P = 0.002 at T20, P < 0.001 at the other times). CONCLUSION: Pre-warming for 30 minutes at 38°C did not modify the trends of the temperature decrease seen in the INR suite. It just slightly elevated the beginning post intubation base temperature. The rate of decrease was similar from T20 to T120. However, pre-warming considerably reduced the risk of intraprocedural hypothermia. TRIAL REGISTRATION: Clinical Research Information Service (CRiS) Identifier: KCT0001320. Registered December 19th, 2014.

Cardiac arrest associated with carbon dioxide gas embolism during laparoscopic surgery for colorectal cancer and liver metastasis -A case report-.

Clinically apparent carbon dioxide (CO(2)) gas embolism is uncommon, but it may be a potentially lethal complication if it occurs. We describe a 40-year-old woman who suffered a CO(2) gas embolism with cardiac arrest during laparoscopic surgery for colorectal cancer and liver metastasis. Intra-abdominal pressure was controlled to less than 15 mmHg during CO(2) gas pneumoperitoneum. The right hepatic vein was accidentally disrupted during liver dissection, and an emergent laparotomy was performed. A few minutes later, the end-tidal CO(2) decreased, followed by bradycardia and pulseless electrical activity. External cardiac massage, epinephrine, and atropine were given promptly. Ventilation with 100% oxygen was started and the patient was moved to the Trendelenburg position. Two minutes after resuscitation was begun, a cardiac rhythm reappeared and a pulsatile arterial waveform was displayed. A transesophageal echocardiogram showed air bubbles in the right pulmonary artery. The patient recovered completely, with no cardiopulmonary or neurological sequelae.

The efficacy of transforaminal epidural steroid injection by the conventional technique in far-lateral herniation of lumbar disc.

BACKGROUND: Owing to the anatomical difference between the far lateral herniation of the lumbar disc (FHLD) and the intraspinal herniation of lumbar disc (iHLD), the outcome of transforaminal epidural steroid injections (TFESI) in patients with FHLD seems to be different from that in patients with iHLD. However, few studies have evaluated the efficacy of TFESI in FHLD. OBJECTIVE: To evaluate and compare the efficacy of TFESI in FHLD and iHLD patients. STUDY DESIGN: A retrospective design. METHODS: There were 15 and 70 patients in the FHLD and iHLD groups, respectively. Patients received a fluoroscopically guided TFESI. Failure rates of TFESI were recorded, and questionnaires, including a visual analog scale (VAS) for leg pain and Oswestry disability index (ODI) were administered before the initial injection, at 2 weeks, 6 weeks, and 12 weeks after the injections. RESULTS: There was no failure for TFESI in the iHLD group, while 9 patients had to undergo alternative blocks in the FHLD group due to lancinating leg pain when the needle was advanced for TFESI. In the iHLD group, there was a statistically significant improvement in the VAS and ODI score 12 weeks after injection. Considering only successful cases of the FHLD group, significant improvement in the VAS and ODI score was also demonstrated in the FHLD group 12 weeks after injection. Moreover, there was no statistically significant difference of the VAS and ODI between the both groups. LIMITATIONS: A relatively small numbers of cases were included in the FHLD group. CONCLUSION: The current study suggests that an alternative needle placement technique for TFESI appears to be necessary for FHLD patients.

Impact of sex, age and BMI on depth and diameter of the infraclavicular axillary vein when measured by ultrasonography.

BACKGROUND AND OBJECTIVE: The axillary vein is another option for central venous catheterisation, with less chance of accidental arterial puncture as there is a greater distance between artery and vein, and from vein to rib cage, compared with other sites. Better success, lower complication rates and faster access can be achieved with ultrasound guidance which is becoming the established technique for central venous catheterisation. We measured two key factors for successful infraclavicular axillary venous catheterisation: depth and diameter of the infraclavicular axillary vein in its medial part using ultrasound. METHODS: We recruited 98 patients, classified according to sex, age and BMI. Groups were divided according to BMI as follows: group 1 (≤20 kg m⁻²), group 2 (20.01-25.00 kg m⁻²) and group 3 (>25 kg m⁻²); and these were further subdivided according to age: 20-39 years, 40-59 years and 60-80 years. The depth and diameter of the infraclavicular axillary vein was measured at a point between the medial third and midpoint of the clavicle. RESULTS: Vein diameter was significantly different between men and women (P = 0.005), whereas depth showed no significant difference. In the BMI subgroups, there was a significant difference in depth (P < 0.001), and a trend to significant difference in diameter (P = 0.056). However, age-specific differences in depth and diameter were not observed. CONCLUSION: During catheterisation of infraclavicular axillary vein, real-time visualisation of the needle tip when using ultrasound to gauge vein depth and diameter may diminish major complications such as pneumothorax and artery puncture.

Left atrial appendage thrombus detected by intraoperative transesophageal echocardiography in a patient with acute small bowel infarction -A case report-.

Acute mesenteric ischemia and infarction is an emergent situation associated with high mortality, commonly due to emboli or thrombosis of the mesenteric arteries. Embolism to the mesenteric arteries is most frequently due to a dislodged thrombus from the left atrium, left ventricle, or cardiac valves. We report a case of 70-year-old female patient with an acute small bowel infarction due to a mesenteric artery embolism dislodged from a left atrial appendage detected by intraoperative transesophageal echocardiography and followed by anticoagulation therapy.

Three-dimensional C-arm computed tomography-guided sacroplasty for the treatment of sacral body fracture.

STUDY DESIGN: Case report. OBJECTIVE: To report our results of a sacroplasty technique, using 3-dimensional C-arm CT for the treatment of sacral body fracture. SUMMARY OF BACKGROUND DATA: Sacroplasty may provide symptomatic relief and hasten recovery in the treatment of sacral insufficiency fractures. To our knowledge, there is no case report in the literature describing the application of sacroplasty for the treatment of sacral body fracture. We present a case of patient who had percutaneous sacroplasty for sacral body fracture and sacral alar fracture under 3-dimensional C-arm CT guidance and discuss the clinical results and technical considerations. METHODS: The procedure included a standard prone positioning of the patient and the area to be treated was prepared in a strictly sterile manner, and a local anesthesia was used. After a small skin incision, an 11-gauge vertebroplasty needle was positioned at the entry point in the sacrum. Then, the needle was inclined, directed, and advanced from the posterior aspect to the anterior aspect of the sacral vertebral body. PMMA cement was incrementally introduced in 0.5 mL aliquots and the volume of PMMA cement injected was total 4 mL. Precise needle placement and PMMA cement injection was performed under the 3-dimensional C-arm CT system and the right sacral alar region was performed in a similar manner. RESULTS: There were no peri-procedural complications occurred and the patient experienced an immediate and substantial pain relief that was persistent during a 12-month follow-up. CONCLUSIONS: 3-dimensional C-arm CT-guided sacroplasty is a safe, practical, and effective solution to treatment of sacral body fracture.

A comparative study on the analgesic effect of continuous intraarticular infusion with ropivacaine, ropivacaine/fentanyl and ropivacaine/fentanyl/ketorolac after arthroscopic shoulder surgery.

BACKGROUND: Arthroscopic shoulder surgery can result in severe postoperative pain. A variety of methods have been used to control pain in postoperative period and the results are variable. The purpose of this study was to compare the relative analgesic efficacies of the postoperative intraarticular infusion of ropivacaine, ropivacaine/fentanyl, and ropivacaine/fentanyl/ketorolac after arthroscopic shoulder surgery. METHODS: Thirty patients undergoing arthroscopic shoulder surgery under general anesthesia were randomly assigned to three groups. At the end of surgery, 0.5% ropivacaine 20 ml was infused into the articular space and a continuous infusion catheter was inserted into intraarticular operated site. After surgery, continuous infusion of 0.5% ropivacaine 100 ml (Group 1, n = 10), 0.5% ropivacaine 100 ml including fentanyl 10 microg/kg (Group 2, n = 10), or 0.5% ropivacaine 100 ml including fentanyl 10 microgram/kg and ketorolac 150 mg (Group 3, n = 10) was started through catheter at rate of 2 ml/hr with bolus dose of 0.5 ml with a lock out time of 15 minutes for 2 days. The level of pain was assessed using a visual analogue scale (VAS) postoperative 2, 6, 12, 24 and 48 hours and the amounts of supplemental analgesics were recorded. RESULTS: The VAS was significantly lower after 2, 6, 12 hours in Group 2 than in Group 1. In Group 3, the VAS was significantly lower all hours than in the other two groups. CONCLUSIONS: The combination of fentanyl and ketorolac with ropivacaine did provide better postoperative analgesia than the other groups after arthroscopic shoulder surgery.