Machine learning approach for predicting post-intubation hemodynamic instability (PIHI) index values: towards enhanced perioperative anesthesia quality and safety.

BACKGROUND: Adequate preoperative evaluation of the post-intubation hemodynamic instability (PIHI) is crucial for accurate risk assessment and efficient anesthesia management. However, the incorporation of this evaluation within a predictive framework have been insufficiently addressed and executed. This study aims to developed a machine learning approach for preoperatively and precisely predicting the PIHI index values. METHODS: In this retrospective study, the valid features were collected from 23,305 adult surgical patients at Peking Union Medical College Hospital between 2012 and 2020. Three hemodynamic response sequences including systolic pressure, diastolic pressure and heart rate, were utilized to design the post-intubation hemodynamic instability (PIHI) index by computing the integrated coefficient of variation (ICV) values. Different types of machine learning models were constructed to predict the ICV values, leveraging preoperative patient information and initiatory drug infusion. The models were trained and cross-validated based on balanced data using the SMOTETomek technique, and their performance was evaluated according to the mean absolute error (MAE), root mean square error (RMSE), mean absolute percentage error (MAPE) and R-squared index (R2). RESULTS: The ICV values were proved to be consistent with the anesthetists' ratings with Spearman correlation coefficient of 0.877 (P < 0.001), affirming its capability to effectively capture the PIHI variations. The extra tree regression model outperformed the other models in predicting the ICV values with the smallest MAE (0.0512, 95% CI: 0.0511-0.0513), RMSE (0.0792, 95% CI: 0.0790-0.0794), and MAPE (0.2086, 95% CI: 0.2077-0.2095) and the largest R2 (0.9047, 95% CI: 0.9043-0.9052). It was found that the features of age and preoperative hemodynamic status were the most important features for accurately predicting the ICV values. CONCLUSIONS: Our results demonstrate the potential of the machine learning approach in predicting PIHI index values, thereby preoperatively informing anesthetists the possible anesthetic risk and enabling the implementation of individualized and precise anesthesia interventions.

Association of Obstructive Sleep Apnea With Postoperative Delirium in Procedures of Moderate-to-High Complexity: A Hospital-Registry Study.

BACKGROUND: Patients suffering from obstructive sleep apnea (OSA) experience chronic sleep disturbances and desaturation, factors that have been associated with postoperative delirium and that can be aggravated after anesthesia for complex procedures. We investigated whether OSA is associated with delirium after anesthesia, and whether this association is modified by procedural complexity. METHODS: Hospitalized patients ≥60 years who underwent general anesthesia or procedural sedation for procedures of moderate-to-high complexity between 2009 and 2020 at a tertiary health care network in Massachusetts were included. The primary exposure was OSA, defined based on International Classification of Diseases ( Ninth/Tenth Revision, Clinical Modification ) ( ICD-9 / 10-CM ) diagnostic codes, structured nursing interviews, anesthesia alert notes, and a validated risk score (BOSTN [body mass index, observed apnea, snoring, tiredness, and neck circumference]). The primary end point was delirium within 7 days after the procedure. Multivariable logistic regression and effect modification analyses adjusted for patient demographics, comorbidities, and procedural factors were applied. RESULTS: A total of 46,352 patients were included, of which 1694 patients (3.7%) developed delirium, 537 (3.2%) with OSA, and 1,157 (4.0%) without OSA. In adjusted analyses, OSA was not associated with postprocedural delirium in the overall cohort (adjusted odds ratio [OR adj ], 1.06; 95% confidence interval [CI], 0.94-1.20; P = .35). However, a high procedural complexity modified the primary association ( P value for interaction = .002). OSA patients had a higher risk of delirium after high-complexity procedures (≥40 work relative value units) such as cardiac (OR adj , 1.33; 95% CI, 1.08-1.64; P = .007, P value for interaction = .005) or thoracic surgery (OR adj , 1.89; 95% CI, 1.19-3.00; P = .007, P value for interaction = .009), but no increased risk after moderate complexity procedures, including general surgery (OR adj , 0.86; 95% CI, 0.55-1.35; P = .52). CONCLUSIONS: Compared to non-OSA patients, a history of OSA is associated with a higher risk after high-complexity procedures such as cardiac or thoracic surgery but not after procedures of moderate complexity.

Constructing green superhydrophilic and superoleophobic COFs-MOFs hybrid-based membrane for efficiently emulsion separation and synchronous removal of microplastics, dyes, and pesticides.

Oil spills and micropollutants have become thorny environmental issues, posing serious threat to ecosystem and human health. To settle such dilemma, this study successfully constructed a robust and environmentally-friendly MOFs-COFs hybrid-based membrane (FS-50/COF(MATPA)-MOF(Zr)/PDA@PVDF) for the first time through solution synthesis and solvothermal method, combined with surface modification of FS-50 molecule. Importantly, we employed a simple two-step strategy to obtain the high-aspect-ratio MOFs fibers: (1) solvent regulation to generate smaller needle-like whiskers during the in-situ growth of MOFs on COFs; (2) high pressure induced directional crystallization in filtration process. The introduction of polydopamine (PDA) greatly improved the adhesion between coating and PVDF membrane. The in-situ growth of high length-diameter ratio MOFs fibers on blocky COFs greatly enhanced the specific surface area of MOFs-COFs hybrid, thus provided sufficient absorption sites. The functional groups of FS-50 endowed the hybrid membrane with superhydrophilicity and superoleophobicity, which facilitated to selectively penetrate water molecules and repel non-polar pollutants. The separation efficiency and decontamination mechanism of hybrid membrane to the simulated oily wastewater (containing various MPs, dyes, and pesticides) were investigated through experiments and theoretical calculations. The hybrid membrane could selectively and synchronously adsorb various dyes (20 mg/L-120 mg/L, almost 100% removal) and pesticides (10 mg/L for DIF and TET, adsorption rates 93.2% and 90.9%, respectively) from oil-water emulsion (50 mL). The large-scale coated sponge (6 cm × 4.5 cm × 3 cm) could quickly achieve separation of oil-water mixture (almost 100%) with a water permeability of more than 162 L m-2·h-1·bar-1, and simultaneously remove various MPs (PP-2000, PP-100, PE-2000, PS-100, 0.2 g/300 mL for each), Sudan Ⅲ (C0 = 200 mg/L), and DIF (C0 = 10 mg/L) from a simulant oily wastewater (300 mL), with the removal rates of almost 100% for MPs, 99.7% for Sudan Ⅲ, and 95.8% for DIF. Furthermore, we elucidated the removal mechanism of pesticide and dyes through simulating the theoretical adsorption energy and potential adsorption sites. The hybrid membrane not only provides a promising candidate for the removal of multiple pollutants from oil-water emulsion, but also opens a new strategy for achieving efficient and clean aquatic environment restoration.

Intraoperative use of phenylephrine versus ephedrine and postoperative delirium: A multicenter retrospective cohort study.

BACKGROUND: The treatment of intraoperative hypotension with phenylephrine may impair cerebral perfusion through vasoconstriction, which has been linked to postoperative delirium. We hypothesized that intraoperative administration of phenylephrine, compared to ephedrine, is associated with higher odds of postoperative delirium. METHODS: 103,094 hospitalized adults undergoing general anesthesia for non-cardiac, non-neurosurgical procedures between 2008 and 2020 at two tertiary academic healthcare networks in Massachusetts, USA were included in this multicenter hospital registry study. The primary exposure was the administration of phenylephrine versus ephedrine during surgery, and the primary outcome was postoperative delirium within seven days. Multivariable logistic regression analyses adjusted for a priori defined confounding variables including patient demographics, comorbidities, and procedural factors including magnitude of intraoperative hypotension were applied. RESULTS: 78,982 (76.6%) patients received phenylephrine, and 24,112 (23.4%) patients received ephedrine during surgery. 770 patients (0.8%) developed delirium within seven days. The median (interquartile range [IQR]) total intraoperative dose of phenylephrine was 1.0 (0.2-3.3) mg and 10.0 (10.0-20.0) mg for ephedrine. In adjusted analyses, the administration of phenylephrine, compared to ephedrine, was associated with higher odds of developing postoperative delirium within seven days (adjusted odds ratio [ORadj] 1.35; 95%CI 1.06-1.71; adjusted absolute risk difference [ARDadj] 0.2%; 95%CI 0.1%-0.3%; p=0.015). A keyword and manual chart review-based approach in a subset of 45,465 patients further validated these findings (delirium incidence 3.2%, ORadj 1.88; 95%CI 1.49-2.37; p<0.001). Fractional polynomial regression analysis further indicated a dose-dependent effect of phenylephrine (adjusted coefficient 0.08; 95%CI 0.02-0.14; p=0.013, per each mcg/kg increase in the cumulative phenylephrine dose). CONCLUSIONS: The administration of phenylephrine compared to ephedrine during general anesthesia was associated with higher odds of developing postoperative delirium. Based on our data, clinical trials are warranted to determine whether favoring ephedrine over phenylephrine for treatment of intraoperative hypotension can reduce delirium after surgery.

Engineering green MOF-based superhydrophobic sponge for efficiently synchronous removal of microplastics and pesticides from high-salinity water.

Microplastics (MPs) and pesticides are becoming an intractable environmental issue due to their wide spreading and non-degradable nature, posing serious threat to ecosystem and human health. To settle such dilemma, this work reasonably designed a superhydrophobic MOF-based coated sponge (ODSOSS/TiO2/Ni-MOF/PDA@Sponge) through the combination of an environmentally friendly in-situ supersaturated coprecipitation and polysesiloxane modification method. Among them, (I) the introduction of polydopamine (PDA) not only improves the adhesion between coatings and sponge, but also enhances the growth of MOF structure through complexation. (II) The obtained Ni-MOF shows large-area microscale anthemy structure with multilayered flaky texture, forming heterogeneously hierarchical structure with the deposited TiO2 nanoparticles, which promotes photodegradation ability of TiO2 owing to great specific surface area of Ni-MOF. (III) The high specific large area Ni-MOF supplies sufficient action sites for linkage of PDA and polysesiloxane molecules with unique nanocage-like structure, thus further greatly increasing adsorption force for various pollutants. (IV) The superhydrophobicity protect the porous channels of MOF from contamination of various absorbed pollutants, while TiO2 nanoparticles effectively photodegrade the absorbed organic pollutants, endowing the sponge superior recyclability. The superhydrophobic sponge selectively rapidly and synchronously adsorbs various MPs (maintained almost 100% after 60 cycles) and pesticides (adsorption rates 71.6%-95.1%) from high-salinity water. The large-area sponge (9 cm × 6 cm × 1 cm) simultaneously removes almost 100% MPs (40 mg/L), Sudan Ⅲ (10 mg/L), kerosene (30 mL/L), and four pesticides (10 mg/L) within 1 min. Particularly, four pesticides are quickly photocatalytic degraded by the coated sponge. The free radical capture trials show that hydroxyl radicals (·OH) are the main active species of pesticide degradation. Furthermore, we reveal the negative centers where pesticide molecules are most vulnerable to ·OH attack, on basis of the charge distribution and molecular electrostatic potential (MEP) analysis. The adsorption mechanisms are carefully clarified through theoretical calculation and experimental data. This work not only provide an effective superhydrophobic candidate for MPs and pesticides removal in a broad applicable scope (especially in high-salinity wastewater), but also opens a new strategy for environmental remediation.

Bias in artificial intelligence algorithms and recommendations for mitigation.

The adoption of artificial intelligence (AI) algorithms is rapidly increasing in healthcare. Such algorithms may be shaped by various factors such as social determinants of health that can influence health outcomes. While AI algorithms have been proposed as a tool to expand the reach of quality healthcare to underserved communities and improve health equity, recent literature has raised concerns about the propagation of biases and healthcare disparities through implementation of these algorithms. Thus, it is critical to understand the sources of bias inherent in AI-based algorithms. This review aims to highlight the potential sources of bias within each step of developing AI algorithms in healthcare, starting from framing the problem, data collection, preprocessing, development, and validation, as well as their full implementation. For each of these steps, we also discuss strategies to mitigate the bias and disparities. A checklist was developed with recommendations for reducing bias during the development and implementation stages. It is important for developers and users of AI-based algorithms to keep these important considerations in mind to advance health equity for all populations.

Prevalence and association of non-medical cannabis use with post-procedural healthcare utilisation in patients undergoing surgery or interventional procedures: a retrospective cohort study.

Background: There is paucity of data regarding prevalence and key harms of non-medical cannabis use in surgical patients. We investigated whether cannabis use in patients undergoing surgery or interventional procedures patients was associated with a higher degree of post-procedural healthcare utilisation. Methods: 210,639 adults undergoing non-cardiac surgery between January 2008 and June 2020 at an academic healthcare network in Massachusetts, USA, were included. The primary exposure was use of cannabis, differentiated by reported ongoing non-medical use, self-identified during structured, preoperative nursing/physician interviews, or diagnosis of cannabis use disorder based on International Classification of Diseases, 9th/10th Revision, diagnostic codes. The main outcome measure was the requirement of advanced post-procedural healthcare utilisation (unplanned intensive care unit admission, hospital re-admission or non-home discharge). Findings: 16,211 patients (7.7%) were identified as cannabis users. The prevalence of cannabis use increased from 4.9% in 2008 to 14.3% by 2020 (p < 0.001). Patients who consumed cannabis had higher rates of psychiatric comorbidities (25.3 versus 16.8%; p < 0.001) and concomitant non-tobacco substance abuse (30.2 versus 7.0%; p < 0.001). Compared to non-users, patients with a diagnosis of cannabis use disorder had higher odds of requiring advanced post-procedural healthcare utilisation after adjusting for patient characteristics, concomitant substance use and socioeconomic factors (aOR [adjusted odds ratio] 1.16; 95% CI 1.02-1.32). By contrast, patients with ongoing non-medical cannabis use had lower odds of advanced post-procedural healthcare utilisation (aOR 0.87; 95% CI 0.81-0.92, compared to non-users). Interpretation: One in seven patients undergoing surgery or interventional procedures in 2020 reported cannabis consumption. Differential effects on post-procedural healthcare utilisation were observed between patients with non-medical cannabis use and cannabis use disorder. Funding: This work was supported by an unrestricted philantropic grant from Jeff and Judy Buzen to Maximilian S. Schaefer.

Cognitive function in older patients and their stress challenge using different anesthesia regimes: a single center observational study.

BACKGROUND: With increasing age older patients are at higher risk for cognitive decline after surgery. Even tailored anesthesia procedures in older patients remain a high risk for postoperative cognitive disorder. Additional stress derived from anxiety and anesthesia itself can negatively impact postoperative cognitive outcomes. The objective of this study was to evaluate the impact of general versus regional anesthesia on postoperative cognitive disorder and indicators of perioperative stress in elderly undergoing surgery. METHODS: In this single center prospective study between December 2014 and November 2015, 46 patients aged 50 to 85 years undergoing dermatology surgery were enrolled. Patients were stratified by receiving general versus regional nerve anesthesia. On three consecutive days, saliva cortisol levels were analyzed three times per day. Cognitive function was assessed on the day before and the day after surgery using comprehensive neuropsychological testing of multiple cognitive functions including memory, executive function, attention and processing speed. RESULTS: Comparing the regional anesthesia group (RAG, n = 28) with the general anesthesia group (GAG, n = 18) no significant difference in the postoperative cognitive function was observed. However, patients in the GAG had significantly higher postoperative cortisol levels when compared to patients in the RAG. In both groups, a peak of cortisol value was detected on the day of surgery, which was higher in the GAG in comparison to the RAG. CONCLUSIONS: We did not observe a difference in postoperative cognitive function between patients undergoing regional or general anesthesia for dermatology surgery. However, we found lower cortisol level in the RAG. Based on these findings, future studies should investigate alternatives to reduce stress in a general anesthesia setting. TRIAL REGISTRATION: ClinicalTrials.gov ID: NCT02505815.

Dose-dependent relationship between intra-procedural hypoxaemia or hypocapnia and postoperative delirium in older patients.

BACKGROUND: Previous studies indicated an association between impaired cerebral perfusion and post-procedural neurological disorders. We investigated whether intra-procedural hypoxaemia or hypocapnia are associated with delirium after surgery. METHODS: Inpatients ≥60 yr of age undergoing anaesthesia for surgical or interventional procedures between 2009 and 2020 at an academic healthcare network in the USA (Massachusetts) were included in this hospital registry study. The primary exposure was intra-procedural hypoxaemia, defined as peripheral oxygen saturation <90% for >2 cohering min. The co-primary exposure was hypocapnia during general anaesthesia, defined as end-tidal carbon dioxide pressure ≤25 mm Hg for >5 cohering min. The primary outcome was delirium within 7 days after surgery. RESULTS: Of 71 717 included patients, 1702 (2.4%) developed postoperative delirium, and hypoxaemia was detected in 2532 (3.5%). Of 42 894 patients undergoing general anaesthesia, 532 (1.2%) experienced hypocapnia. The occurrence of either hypoxaemia (adjusted odds ratio [ORadj]=1.71; 95% confidence interval [CI], 1.40-2.07; P<0.001) or hypocapnia (ORadj=1.77; 95% CI, 1.30-2.41; P<0.001) was associated with a higher risk of delirium within 7 days. Both associations were dependent on the magnitude, and increased with event duration (ORadj=1.03; 95% CI, 1.02-1.04; P<0.001 and ORadj=1.01; 95% CI, 1.00-1.01; P=0.005, for each minute increase in the longest continuous episode, respectively). There was no association between occurrence of hypercapnia and postoperative delirium (ORadj=1.24; 95% CI, 0.90-1.71; P=0.181). CONCLUSIONS: Intra-procedural hypoxaemia and hypocapnia were dose-dependently associated with a higher risk of postoperative delirium. These findings support maintaining normal gas exchange to avoid postoperative neurological disorders.

Using ketamine in a patient with a near-occlusion tracheal tumor undergoing tracheal resection and reconstruction: A case report.

BACKGROUND: Tracheal tumors may cause airway obstruction and pose a significant risk to ventilation and oxygenation. Due to its rarity, there is currently no established protocol or guideline for anesthetic management of resection of upper tracheal tumors, therefore individualized strategies are necessary. There are limited number of reports regarding the anesthesthetic management of upper tracheal resection and reconstruction (TRR) in the literature. We successfully used intravenous ketamine to manage a patient with a near-occlusion upper tracheal tumor undergoing TRR. CASE SUMMARY: A 25-year-old female reported progressive dyspnea and hemoptysis. Bronchoscopy showed an intratracheal tumor located one tracheal ring below the glottis, which occluded > 90% of the tracheal lumen. The patient was scheduled for TRR. Considering the risk of complete airway collapse after the induction of general anesthesia, we decided to secure the airway with a tracheostomy with spontaneous breathing. The surgeons needed to transect the trachea 1-2 cartilage rings below and above the tumor borders: a time-consuming process. Coughing and movement needed be minimized; thus, we added intravenous ketamine to local anesthetic infiltration. After tracheostomy, an endotracheal tube was placed into the distal trachea, and general anesthesia was induced. The surgeons resected four cartilage rings with the tumor attached and anastomosed the posterior tracheal wall. We performed a video-laryngoscopy to place a new endotracheal tube. Finally, the surgeons anastomosed the anterior tracheal walls. The patient was extubated uneventfully. CONCLUSION: Ketamine showed great advantages in the anesthesia of upper TRR by providing analgesia with minimal respiratory depression or airway collapse.

The effect of intraoperative dexmedetomidine administration on length of stay in the post-anesthesia care unit in ambulatory surgery: A hospital registry study.

STUDY OBJECTIVE: Dexmedetomidine, which is commonly used for procedural sedation and as adjunct to general anesthesia for ambulatory procedures, may affect patient discharge from the post-anesthesia care unit (PACU). We hypothesized that intraoperative dexmedetomidine use in ambulatory surgery is associated with delayed discharge from the PACU and that this is modified by surgical duration and anesthesia type. DESIGN: Retrospective cohort study. SETTING: Academic medical center. PATIENTS: 130,854 adult patients undergoing ambulatory surgery between 2008 and 2018. INTERVENTIONS: Intraoperative administration of dexmedetomidine. MEASUREMENTS: The primary outcome was PACU length of stay. In secondary and exploratory analyses, we examined dose-dependency, effect modification by duration of surgery and anesthesia type, effects of timing of dexmedetomidine administration, and PACU discharge delays. MAIN RESULTS: Dexmedetomidine was associated with a prolonged PACU length of stay (adjusted absolute difference [ADadj] 15.0 min; 95%CI 12.7-17.3; p < 0.001). This effect was dose-dependent (p-for-trend < 0.001), magnified in surgeries of less than one hour (ADadj 20.7 min; 95%CI 16.7-24.7; p < 0.001) and in patients undergoing monitored anesthesia care compared to general anesthesia (ADadj 16.8 min; 95%CI 14.1-19.6; p < 0.001). The effect was more pronounced if dexmedetomidine was administered within the last 60 min of surgery (ADadj 18.7 min; 95%CI 15.7-21.7; p < 0.001). Dexmedetomidine was associated with discharge delays due to cardiovascular complications (ORadj 2.27; 95%CI 1.59-3.24; p < 0.001) and over-sedation (ORadj 1.28; 95%CI 1.11-1.48; p < 0.001). In patients who received dexmedetomidine (n = 2901), the use of bolus doses only versus the combination of bolus and infusions, magnified the effects on PACU length of stay (ADadj 29.5 min per µg/kg; 95%CI 17.3-41.8 versus 18.1 min per µg/kg; 95%CI 11.4-24.8; p < 0.001). CONCLUSIONS: The intraoperative administration of dexmedetomidine was dose-dependently associated with a prolonged PACU length of stay. Clinicians should judiciously titrate dexmedetomidine, especially when using this long-acting drug for monitored anesthesia care for shorter procedures.

Identifying the Gap Between Novices and Experts in Fiberoptic Scope Control.

BACKGROUND: Fiberoptic intubation (FOI) is key in managing difficult airways. Good scope control increases efficiency and patient safety. Understanding the gap between novices and experts in scope control would help medical educators develop a feedback-based teaching approach for novices. We designed and used a checklist for evaluating the gap in fiberoptic scope control between novices and experts. METHODS: Twelve first-year anesthesiology residents (novice group) attended a lecture, followed by hands-on practice with a fiberoptic scope on a manikin. Five staff anesthesiologists (expert group) only did the hands-on practice. After practice, each participant was video-recorded while conducting an FOI on the manikin. Two senior anesthesiologists developed and used a 7-item checklist to assess the FOIs. Checklist scores and total times for FOIs were compared between groups using the Mann-Whitney U test. Internal consistency of the checklist items, interrater reliability, and the relationship between checklist score and total time for FOI were assessed with Cronbach alpha, Cohen kappa, and the Pearson correlation coefficient, respectively. RESULTS: Experts had higher checklist scores than novices (P = .0016). The item with the lowest success rate for novices (50%) was keeping the scope straight. Novices spent more time on the FOI than experts (P = .0005). Cronbach alpha, Cohen kappa, and the Pearson correlation coefficient were 0.8699, 0.75, and -0.9454, respectively. CONCLUSIONS: Our checklist was used to detect differences in fiberoptic scope control skills between novices and experts. With a video-based assessment method, it can be used to develop a feedback-based teaching method for fiberoptic scope control.

Using Lumbar X-Ray to Facilitate Modified Taylor's Approach of Spinal Anesthesia in an Elderly Patient With Scoliosis.

In geriatric patients scheduled for hip or knee surgery, neuraxial anesthesia is a safe and effective anesthesia method and may be a better option than general anesthesia. Unfortunately, establishing neuraxial anesthesia is not always easy in this group of patients. Anatomical abnormalities, such as spinal stenosis, scoliosis, and narrowed interspaces, contribute to the difficulties that anesthesiologists face while performing these procedures. The classic Taylor's approach targets the widest interspace, L5-S1, as the needle insertion site and accordingly has an increased success rate in difficult neuraxial anesthesia. As this technique historically relies solely on palpation, it might be difficult in patients with less prominent or distorted anatomic landmarks. Ultrasonography or fluoroscopy guidance may help to better target the epidural or subarachnoid space, but both have limitations due to equipment availability or provider expertise. The modified Taylor's approach we propose in this case report is based on preoperative lumbar x-ray interpretation when point-of-care image guidance cannot be performed. By measuring on the patient's preoperative lumbar x-ray, we successfully performed a modified Taylor's approach of spinal anesthesia on an elderly patient with severe scoliosis. She underwent open reduction and internal fixation (ORIF) of the left femur with satisfactory pain control and no complications.

Infective endocarditis at a tertiary-care hospital in China.

BACKGROUND: The aim of this study was to describe the clinical features and outcome of infective endocarditis at a general hospital in China and to identify the risk factors associated with in-hospital mortality. METHODS: A retrospective study was conducted and all patients diagnosed with definite or possible infective endocarditis between January 2013 and June 2018 according to the modified Duke criteria were included. RESULTS: A total of 381 patients were included. The mean age was 46 years old and 66.9% patients were male patients. Community acquired IE was the most common type of infective endocarditis and Viridans Group Streptococci (37.5%) was still the most common causative pathogen. The microbial etiology of infective endocarditis varied with location of acquisition. 97 (25.5%) patients had culture-negative infective endocarditis. Vegetations were detected in 85% patients and mitral valve was the most common involved valve. Operations were performed in 72.7% patients and in-hospital mortality rate was 8.4%. The risk factors of in-hospital mortality were age old than 70 years old, heart failure, stroke and medical therapy. CONCLUSIONS: Older age, heart failure, stroke and medical therapy were risk factors of in-hospital mortality. Infective endocarditis, were mainly caused by Viridans Group Streptococci, characterized by younger patients and lower mortality rate in China.

Analysis of patient injury based on anesthesiology closed claims data from a major malpractice insurer.

INTRODUCTION: The analysis of malpractice claims can provide risk managers with a detailed view of patient mortality and morbidity. The data comes from many institutions, encompasses a diverse group of practitioners and practice settings, and contains detailed clinical information. Analysis can help identify patterns of injury, risk factors, and rare and sentinel events. METHODS: We examined most recent anesthesia closed claims data collected by The Doctors Company, a large national malpractice insurer. We analyzed data from claims closed between 2007 and 2012. Each claim underwent a review by physician and nurse experts, and was then coded using the Comprehensive Risk Intelligence Tool. Injury distribution and association between the injury and patient comorbidity were also examined. RESULTS: A total of 607 claims were analyzed. Most frequent injuries were teeth damage (20.8%), death (18.3%), nerve damage (13.5%), organ damage (12.7%), pain (10.9%), and arrest (10.7%). Obesity was most frequently identified as a contributing factor leading to a claim. Injury-to-claim rates were highest in hospitals with fewer than 100 beds, while ambulatory surgery centers had the lowest death-to-claim rate (12%). Average indemnity for an anesthesia claim was $309 066, compared to $291 000 for all physician specialties. CONCLUSIONS: The most frequent claims were death and nerve damage when teeth damage was excluded. Obesity impacted anesthesia outcomes more frequently than did other comorbidities. Although there were fewer claims from the smaller hospitals, those claims had higher rates of mortality and nerve damage compared to larger-size hospitals. Further analysis is needed to evaluate these trends as well as impact of specific patient comorbidities on anesthesia outcomes.

Quantitative analysis of continuous intravenous infusions in pediatric anesthesia: safety implications of dead volume, flow rates, and fluid delivery.

OBJECTIVE: Quantitative characterization of continuous pediatric drug infusions. BACKGROUND: The dynamics of drug delivery by continuous infusion to pediatric patients have not been systematically examined. This study extends previously described analytic models to propofol and remifentanil delivery, focusing on infants and toddlers. We postulated that infusion system dead volume, and drug and carrier flow rates, significantly influence drug delivery. METHODS: We studied effects of patient weight, infusion system dead volume, drug and carrier flow rates, along with drug stock concentration and dose, on propofol and remifentanil delivery to the circulation. We calculated the drug mass available for inadvertent bolus in the dead volume, the volume of fluid supplied by drug infusions, and model-based estimates of the range of lag times to achieve a targeted steady-state rate of drug delivery. RESULTS: The drug mass in the dead volume at steady state increased with dead volume size and drug dose. For infants, this drug mass could exceed 100% of commonly used loading doses. Predicted lag times to steady state depend on patient size, fluid flow rates, and the mixing behavior of the drug entering the main fluid pathway. Neonates have the longest lag times to achieve steady state. Fluid quantities delivered by drug infusions increase with drug flow rate and can represent a large fraction of estimated maintenance fluid requirements. Fluid delivery increases if stock drug concentrations are diluted. These relationships were qualitatively similar for propofol and remifentanil. CONCLUSIONS: Traditional studies focus on drug disposition once a drug enters the circulation. Our analysis shows the potential importance of factors influencing drug delivery to the patient's circulation, focusing on propofol and remifentanil administration to small patients. The drug mass available for inadvertent bolus residing in the reservoir of the dead volume at steady state may be large and clinically relevant. Lag times to achieve steady-state delivery are long, depending on the infusion system's architecture and fluid flow rates. By themselves, drug infusions can deliver significant fluid loads to children. These observations have practical and perhaps safety implications for infusions of drugs commonly administered to infants and children.

Detection of pneumonia using free-text radiology reports in the BioSense system.

OBJECTIVE: Near real-time disease detection using electronic data sources is a public health priority. Detecting pneumonia is particularly important because it is the manifesting disease of several bioterrorism agents as well as a complication of influenza, including avian and novel H1N1 strains. Text radiology reports are available earlier than physician diagnoses and so could be integral to rapid detection of pneumonia. We performed a pilot study to determine which keywords present in text radiology reports are most highly associated with pneumonia diagnosis. DESIGN: Electronic radiology text reports from 11 hospitals from February 1, 2006 through December 31, 2007 were used. We created a computerized algorithm that searched for selected keywords ("airspace disease", "consolidation", "density", "infiltrate", "opacity", and "pneumonia"), differentiated between clinical history and radiographic findings, and accounted for negations and double negations; this algorithm was tested on a sample of 350 radiology reports. We used the algorithm to study 189,246 chest radiographs, searching for the keywords and determining their association with a final International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) diagnosis of pneumonia. MEASUREMENTS: Performance of the search algorithm in finding keywords, and association of the keywords with a pneumonia diagnosis. RESULTS: In the sample of 350 radiographs, the search algorithm was highly successful in identifying the selected keywords (sensitivity 98.5%, specificity 100%). Analysis of the 189,246 radiographs showed that the keyword "pneumonia" was the strongest predictor of an ICD-9-CM diagnosis of pneumonia (adjusted odds ratio 11.8) while "density" was the weakest (adjusted odds ratio 1.5). In general, the most highly associated keyword present in the report, regardless of whether a less highly associated keyword was also present, was the best predictor of a diagnosis of pneumonia. CONCLUSION: Empirical methods may assist in finding radiology report keywords that are most highly predictive of a pneumonia diagnosis.

NLP-based identification of pneumonia cases from free-text radiological reports.

Radiological reports are a rich source of clinical data which can be mined to assist with biosurveillance of emerging infectious diseases. In addition to biosurveillance, radiological reports are an important source of clinical data for health service research.Pneumonias and other radiological findings on chest x ray or chest computed tomography (CT) are one type of relevant finding to both biosurveillance and health services research. In this study we examined the ability of a Natural Language Processing system to accurately identify pneumonias and other lesions from within free text radiological reports. The system encoded the reports in the SNOMED CT Ontology and then a set of SNOMED CT based rules were created in our Health Archetype Language aimed at the identification of these radiological findings and diagnoses. The encoded rule was executed against the SNOMED CT encodings of the radiological reports. The accuracy of the reports was compared with a Clinician review of the Radiological Reports. The accuracy of the system in the identification of pneumonias was high with a Sensitivity (recall) of 100%, a specificity of 98%, and a positive predictive value (precision) of 97%. We conclude that SNOMED CT based computable rules are accurate enough for the automated biosurveillance of pneumonias from radiological reports.

Implementation of laboratory order data in BioSense Early Event Detection and Situation Awareness System.

INTRODUCTION: Laboratory test orders constitute an early outbreak data source. CDC receives laboratory order data in HL7 format from the Laboratory Corporation of America (LabCorp) and plans to use the data in the BioSense Early Event Detection and Situation Awareness System. METHODS: These LabCorp data contain information on tests ordered and include the type of test ordered and the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM)-coded reasons for the order. A consensus panel was formed to group test orders on the basis of expert opinion into eight standard syndrome categories to provide an additional data source for early outbreak detection. A laboratory order taxonomy was developed and used in the mapping consolidation phase. The five main classes of this taxonomy are miscellaneous functional tests, fluid screening tests, system-specific tests, tests for specific infections (by primary manifestation), and tests for specific noninfectious diseases. RESULTS: Summary of numbers of laboratory order codes in each syndrome category are fever (53), respiratory (53), gastrointestinal (27), neurological (35), rash (37), lymphadenitis (20), localized cutaneous lesion (11), and specific infection (63). CONCLUSION: With the daily use of laboratory order data in BioSense, the actual distribution of laboratory order codes in syndrome groups can be evaluated, allowing modification of the mapping.