Anterior knee pain post-multiple surgeries for tibia fracture effectively managed with infrapatellar fat pad injection: a case report.

BACKGROUND: The anterior knee compartment is filled by the infrapatellar fat pad (IFP) and has been emphasized as a source of anterior knee pain (AKP). CASE PRESENTATION: A 51-year-old woman sustained a right tibial plateau and open diaphyseal fracture 2 years earlier. She remained with chronic AKP after undergoing bone fixations. Increased anterior portion of the IFP brightness and decreased adipose tissue gliding with flexion and extension compared to the unaffected side was shown on ultrasonography. An injection of 0.2% lidocaine between the patellar tendon and IFP, and into the IFP under ultrasound guidance, immediately relieved the pain. The pain kept recurring although injections were effective for a while; thus, surgery was scheduled. Scar tissue on the IFP surface was endoscopically excised and her pain dramatically reduced. CONCLUSION: This is the first report in which the detection of increased brightness on ultrasound of IFP and the injections into the IFP triggered an additional surgical intervention. Ultrasound evaluation and injection may be beneficial in pain clinic patients presenting with AKP and may provide an opportunity for diagnosis.

Evaluation of microbial contamination on cuff syringe, cuff pressure gauge, and their surroundings in the operating room.

BACKGROUND: Some institutions reuse cuff syringes and do not periodically sterilize cuff pressure gauges. Pathogenic bacterial contamination of such equipment may increase the probability of pathogen transmission to patients during anesthetic procedures. Therefore, microbial contamination on cuff syringes, cuff pressure gauges, and their surroundings was assessed in the operating rooms of a university-affiliated tertiary care hospital in Japan. METHODS: This study was conducted between April and May 2019 in 14 operating suites at a hospital. The following sites in each operating suite were sampled: cuff syringe (inner/outer components), outer components of cuff pressure gauge, cuff syringe and cuff pressure gauge storage drawers, and computer mice. The swabs were directly streaked onto agar plates and incubated. Then, the bacterial species were identified using mass spectrometry. RESULTS: The highest bacterial isolation was observed in computer mice, followed by the outside of cuff pressure gauges and the drawers of cuff pressure gauges (92.9, 78.6, and 64.3%, respectively). Most of the identified bacteria belonged to the Bacillus species, with colonization rates of 85.7, 57.1, and 57.1% on computer mice, cuff pressure gauges, and cuff pressure gauge storage drawers, respectively. Coagulase-negative Staphylococcus was found in 35.7% of the specimens and was more prevalent on computer mice (71.4%), followed by on cuff pressure gauges (64.3%). CONCLUSION: Anesthesiologists should be aware of the possible pathogen contamination risk from cuff syringes, cuff pressure gauges, or associated equipment and take appropriate infection control measures to minimize the risk of pathogenic transmission.

Update on the SedLine® algorithm for calculating the Patient State Index of older individuals during general anesthesia: a randomized controlled trial.

BACKGROUND: The SedLine® sensor processes (Masimo Corporation; Irvine, CA, USA) raw electroencephalogram (EEG) signals and displays the depth of sedation as a Patient State Index (PSi). Reliance on standard processed EEG data and failure to recognize age-related effects can lead to an erroneous interpretation that low-amplitude EEG findings in an older patient signify an insufficient depth of anesthesia presented as abnormally high PSi values (AHPSi). We hypothesized that the incidence of AHPSi would decrease with the use of the recently-updated version of the SedLine® sensor, in which the Bispectral Index (BIS) values were used to titrate anesthesia. METHODS: Thirty-three patients undergoing sevoflurane-remifentanil anesthesia were randomized into two groups. SedLine® sensors designed based on an old (v.1203) or updated (v.2000) algorithms were used. The BIS (v.4.1) and absolute index of total EEG power (TP) were simultaneously recorded. The attending anesthesiologists titrated the anesthetics, and BIS was maintained at 40-60. The incidence of AHPSi (PSi>50 with BIS 40-60) was calculated during the first 30 min after the start of surgery. RESULTS: Compared to the old algorithm group, the incidence of AHPSi was significantly lower in the updated algorithm group (26.7% vs. 4.2%, P<0.001). Lower TP values and the use of the old algorithm have significant effect on increased PSi values (P<0.001). CONCLUSIONS: The incidence of AHPSi decreased with the use of the updated version of the SedLine® algorithm.

Transient maintenance of tracheal patency upon the insertion of a flexible bronchoscope in a patient with an anterior mediastinal mass: a case report.

BACKGROUND: Patients with an anterior mediastinal mass are at risk of perioperative respiratory collapse. CASE PRESENTATION: A 74-year-old woman with a large anterior mediastinal mass that led to partial tracheal collapse (shortest diameter, 1.3 mm) was scheduled for tracheobronchial balloon dilation and stent placement under general anesthesia. Although veno-venous extracorporeal membrane oxygenation (V-V ECMO) had been established, maximum flow was limited to 1.6 L/min, and general anesthesia induction was followed by hypoxia probably due to inadequate ventilation. A flexible bronchoscope was inserted through the tracheal lumen that was being compressed by the anterior mass; this not only increased tracheal patency but also enabled positive pressure ventilation and resulted in recovery from hypoxia. Scheduled procedures were successfully performed without complications. CONCLUSION: We describe a case wherein tracheal patency was transiently maintained by inserting a flexible bronchoscope in a patient with an anterior mediastinal mass.

Usefulness of oxygen reserve index (ORi™), a new parameter of oxygenation reserve potential, for rapid sequence induction of general anesthesia.

The oxygen reserve index (ORi™) is a new parameter for monitoring oxygen reserve noninvasively. The aim of this study was to examine the usefulness of ORi for rapid sequence induction (RSI). Twenty adult patients who were scheduled for surgical procedures under general anesthesia were enrolled. After attaching a sensor capable of measuring ORi, oxygen (6 L/min) and fentanyl (2 µg/kg) were administered. After 3 min, propofol 2 mg/kg and rocuronium 1 mg/kg were administered without ventilation. Regardless of changes in ORi, tracheal intubation was performed either 2 min after administration of propofol or when percutaneous oxygen saturation (SpO2) reached 98%. Ventilation was then provided with oxygen at 6 L/min, and trends in ORi and SpO2 during RSI were observed. Data from 16 of the 20 patients were analyzed. Before oxygen administration, the median SpO2 was 98% [interquartile range (IQR) 97-98] and ORi was 0.00 in all patients. At 3 min after starting oxygen administration, the median SpO2 was 100% (IQR 100-100) and the median ORi was 0.50 (IQR 0.42-0.57). There was an SpO2 decline of 1% or more from the peak value after propofol administration in 13 patients, and 32.5 s (IQR 18.8-51.3) before the SpO2 decrease, ORi began to decline in 10 of the 13 (77%) patients. The ORi trends enable us to predict oxygenation reduction approximately 30 s before SpO2 starts to decline. By monitoring ORi, the incidence related to hypoxemia during RSI could be reduced.

Effects of indigo carmine intravenous injection on oxygen reserve index (ORi™) measurement.

To retrospectively investigate the effects of indigo carmine intravenous injection on oxygen reserve index (ORi™) in 20 patients who underwent elective gynecologic surgery under general anesthesia. The study subjects were patients who underwent elective gynecologic surgery under general anesthesia between April 2016 and January 2017, and were administered a 5-ml intravenous injection of 0.4% indigo carmine for clinical purposes during surgery with ORi monitoring. Changes in ORi within 20 min after indigo carmine injection were observed. A relevant decrease in ORi was defined as ≥ 10% reduction in ORi from pre-injection level. ORi rapidly decreased after indigo carmine intravenous injection in all patients. In 10 of 19 patients, ORi decreased to 0 after indigo carmine injection. The median lowest value of ORi was 0 (range 0-0.16) and the median time to reach the lowest value of ORi was 2 min (range 1-4 min) after injection. ORi values returned to pre-injection levels within 20 min in 13 of 19 patients, and the median time to return to pre-injection levels was 10 min (range 6-16 min) after injection. During ORi monitoring it is necessary to consider the rapid reduction in ORi after intravenous injection of indigo carmine.

Effects of indigo carmine intravenous injection on noninvasive and continuous total hemoglobin measurement.

The effects of an intravenous injection of indigo carmine on noninvasive and continuous total hemoglobin (SpHb) measurement were retrospectively evaluated. The subjects were 21 patients who underwent elective gynecologic surgery under general anesthesia. During surgery, 5 mL of 0.4 % indigo carmine was intravenously injected, and subsequent changes in SpHb concentrations were evaluated. The results demonstrate that the pre-injection SpHb level was 10 g/dL, and the minimum post-injection SpHb level was 8.3 g/dL. The amount of decrease was 1.8 g/dL. The time to reach the minimum value was 4 min, and the time to return to the pre-injection value was 15 min. The decrease in SpHb was greater in the group with a perfusion index (PI) < 1.4 than in the group with a PI > 1.4. The assessment of SpHb after an intravenous injection of indigo carmine necessitates caution.

THE EFFECT OF OBESITY ON DOSE OF DEXMEDETOMIDINE WHEN ADMINISTERED WITH FENTANYL DURING POSTOPERATIVE MECHANICAL VENTILATION--RETROSPECTIVE.

We carried out a retrospective investigation on the effect of obesity on dexmedetomidine (DEX) requirements when administered with fentanyl (FEN) during mechanical ventilation after major surgeries. After Institutional Review Board approval, 14 obese patients with a body mass index (BMI) ≥ 30 kg/m(2) and the same number of non-obese patients with similar backgrounds to the obese patients were selected from medical records. Doses of DEX in the first 48 h or until the end of sedation or extubation were calculated for comparison. In addition to comparison of dosing between the groups, associations between total body weight (TBW), BMI, and lean body mass (LBM) values and doses of DEX (mcg/h), between BMI and various indices (i.e., amount per TBW per hour and amount per LBM per hour) of DEX doses, and between above indices of DEX and FEN doses were also examined. There were no significant differences in DEX dose indices between the groups. However, DEX requirements (mcg/h) were significantly increased with TBW (kg) (r = 0.51, P = 0.003), BMI (r = 0.49, P = 0.006) and LBM (kg) (r = 0.42, P = 0.02), which might have enhanced the DEX metabolism with physiological changes with obesity. These findings will be beneficial for future clinical pharmacological analysis of DEX.