Relationship between preinduction electroencephalogram patterns and propofol sensitivity in adult patients.

PURPOSE: To determine the precise induction dose, an objective assessment of individual propofol sensitivity is necessary. This study aimed to investigate whether preinduction electroencephalogram (EEG) data are useful in determining the optimal propofol dose for the induction of general anesthesia in healthy adult patients. METHODS: Seventy healthy adult patients underwent total intravenous anesthesia (TIVA), and the effect-site target concentration of propofol was observed to measure each individual's propofol requirements for loss of responsiveness. We analyzed preinduction EEG data to assess its relationship with propofol requirements and conducted multiple regression analyses considering various patient-related factors. RESULTS: Patients with higher relative delta power (ρ = 0.47, p < 0.01) and higher absolute delta power (ρ = 0.34, p = 0.01) required a greater amount of propofol for anesthesia induction. In contrast, patients with higher relative beta power (ρ = -0.33, p < 0.01) required less propofol to achieve unresponsiveness. Multiple regression analysis revealed an independent association between relative delta power and propofol requirements. CONCLUSION: Preinduction EEG, particularly relative delta power, is associated with propofol requirements during the induction of general anesthesia. The utilization of preinduction EEG data may improve the precision of induction dose selection for individuals.

Effect of end-tidal carbon dioxide level on the optic nerve sheath diameter measured by transorbital ultrasonography in anesthetized pediatric patients: A randomized trial.

BACKGROUND: Intraoperative hypercapnia and hypocapnia are common during pediatric anesthesia, and the cerebral blood flow and intracranial pressure may be affected by the partial pressure of arterial carbon dioxide. Transorbital ultrasound measurement of the optic nerve sheath diameter is a simple and non-invasive method for intracranial pressure assessment. The objective of this study was to evaluate the effect of end-tidal carbon dioxide (ET CO2 ) on optic nerve sheath diameter in a healthy anesthetized pediatric population. METHODS: Pediatric patients scheduled for elective surgery under general anesthesia and mechanical ventilation in the supine position were enrolled and divided into four subgroups; age <2 years, 2-6 years, 6-12 years, and 12-18 years. Mechanical ventilation was adjusted to achieve target ET CO2 levels in a randomized sequence (40-35-45-40 mmHg or 40-45-35-40 mmHg). Three minutes after reaching each target ET CO2 level, transorbital ultrasound images of optic nerve sheath diameter were obtained and analyzed. The primary outcome was the optic nerve sheath diameter at each ET CO2 level. RESULTS: Sixty-four pediatric patients were enrolled and analyzed. At ET CO2  = 40 mmHg, the optic nerve sheath diameter was 5.6 ± 0.6 mm, 6.4 ± 0.5 mm, 6.8 ± 0.6 mm, and 7.1 ± 0.5 mm in children aged <2 years, 2-6 years, 6-12 years, and 12-18 years, respectively. The overall percent decreases in the optic nerve sheath diameter was -5.6 ± -4.3% (95% CI; -6.7 to -4.5%) at ET CO2  = 35 mmHg while the overall percent increases of optic nerve sheath diameter (ONSD) was 4.9 ± 5.1% (95% CI; 3.6 to 6.1%) at ET CO2  = 45 mmHg compared with those at ET CO2  = 40 mmHg. Spearman rank correlation analysis indicated that there were weak to moderate correlation between ET CO2 and the optic nerve sheath diameter (correlation coefficient [p-value] = .355 [.004], .318 [.014], .373 [<.001], and .420 [<.001] in children aged <2 years, 2-6 years, 6-12 years, and 12-18 years, respectively). CONCLUSIONS: The optic nerve sheath diameter measured by transorbital ultrasound showed rapid reactivity from ET CO2 35 to 45 mmHg in healthy pediatric patients under inhalation general anesthesia.

Intraoperative hyperglycemia in patients with an elevated preoperative C-reactive protein level may increase the risk of acute kidney injury after cardiac surgery.

PURPOSE: The effect of hyperglycemia on acute kidney injury (AKI) in patients undergoing cardiac surgery is unclear and may involve as yet unexplored factors. We hypothesized differential effects of intraoperative hyperglycemia on AKI after cardiac surgery depending on baseline inflammatory status, as reflected by the C-reactive protein (CRP) level. METHODS: This retrospective study included patients who underwent cardiac surgery seen at our hospital from 2008 to 2018. Patients were classified into four groups according to their preoperative CRP level (≥ 1 or < 1 mg/dl) and their intraoperative time-weighted average glucose concentration (> 140 or ≤ 140 mg/dl): low CRP and normoglycemia, low CRP and hyperglycemia, high CRP and normoglycemia, and high CRP and hyperglycemia. The data were analyzed by multivariable logistic regression analysis. RESULTS: The data of 3625 patients were analyzed. The logistic regression showed that patients in the high CRP and hyperglycemia group had a significantly higher risk of AKI than patients in the low CRP and normoglycemia group [odds ratio (OR), 1.58; 95% confidence interval (CI) 1.10-2.27], low CRP with hyperglycemia group (OR, 1.69; 95% CI 1.16-2.47) and high CRP with normoglycemia group (OR, 1.50; 95% CI 1.01-2.23). CONCLUSIONS: Intraoperative hyperglycemia in patients with an elevated preoperative CRP level was significantly related to an increased risk of AKI after cardiac surgery. Individualized perioperative glycemic control may therefore be necessary in these patients.

Clinical performance of Ambu AuraGainTM versus i-gelTM in anesthetized children: a prospective, randomized controlled trial.

BACKGROUND: Ambu AuraGain and i-gel have different characteristics in design each other. However, few reports evaluate which device has more benefits for ventilation in children undergoing paralyzed general anesthesia. This prospective, randomized controlled trial compared the clinical performance AuraGain and i-gel in anesthetized children. METHODS: Children aged between 1 month and 7 years undergoing elective surgery were randomly assigned to the AuraGain and i-gel groups. The primary outcome was initial oropharyngeal leak pressure (OLP). Secondary outcomes were OLP at 10 min post-insertion, first-attempt and total insertion success rates, number of attempts and ease of gastric suction catheter placement, peak inspiratory pressure, fiberoptic bronchoscopic view score, ventilation quality, requirement of additional manipulation post-insertion, and complications. RESULTS: Data of 93 patients were analyzed. The initial OLPs of the AuraGain and i-gel were 27.5 ± 7.7 and 25.0 ± 8.0 cmH2O, respectively (P = 0.130). The OLP was significantly increased 10 min post-insertion in both groups. The initial success rates of the AuraGain and i-gel insertion were comparable. Suction catheter placement via the gastric port was easier (P = 0.018) and fiberoptic bronchoscopic view was better with the AuraGain (P < 0.001). The i-gel required additional manipulations post-insertion (P = 0.038). The incidence of complications during the emergence period was 10.8% for the i-gelTM and 2.2% for the AuraGain (P = 0.1). CONCLUSIONS: OLP is comparable between AuraGain and i-gel. The AuraGain would be more favorable than the i-gelTM for use in pediatric patients under general anesthesia considering other outcomes.

The association between hospital case volume and in-hospital and one-year mortality after hip fracture surgery.

AIMS: Hospital case volume is shown to be associated with postoperative outcomes in various types of surgery. However, conflicting results of volume-outcome relationship have been reported in hip fracture surgery. This retrospective cohort study aimed to evaluate the association between hospital case volume and postoperative outcomes in patients who had hip fracture surgery. We hypothesized that higher case volume would be associated with lower risk of in-hospital and one-year mortality after hip fracture surgery. METHODS: Data for all patients who underwent surgery for hip fracture from January 2008 to December 2016 were extracted from the Korean National Healthcare Insurance Service database. According to mean annual case volume of surgery for hip fracture, hospitals were classified into very low (< 30 cases/year), low (30 to 50 cases/year), intermediate (50 to 100 cases/year), high (100 to 150 cases/year), or very high (> 150 cases/year) groups. The association between hospital case volume and in-hospital mortality or one-year mortality was assessed using the logistic regression model to adjust for age, sex, type of fracture, type of anaesthesia, transfusion, comorbidities, and year of surgery. RESULTS: Between January 2008 and December 2016, 269,535 patients underwent hip fracture surgery in 1,567 hospitals in Korea. Compared to hospitals with very high volume, in-hospital mortality rates were significantly higher in those with high volume (odds ratio (OR) 1.10, 95% confidence interval ((CI) 1.02 to 1.17, p = 0.011), low volume (OR 1.22, 95% CI 1.14 to 1.32, p < 0.001), and very low volume (OR 1.25, 95% CI 1.16 to 1.34, p < 0.001). Similarly, hospitals with lower case volume showed higher one-year mortality rates compared to hospitals with very high case volume (low volume group, OR 1.15, 95% CI 1.11 to 1.19, p < 0.001; very low volume group, OR 1.10, 95% CI 1.07 to 1.14, p < 0.001). CONCLUSION: Higher hospital case volume of hip fracture surgery was associated with lower in-hospital mortality and one-year mortality in a dose-response fashion. Cite this article: Bone Joint J 2020;102-B(10):1384-1391.