Hydropneumopericardium Due to a Traumatic Esophageal-Pericardial Fistula

Esophago-pericardial fistula is a rare, life-threatening condition, usually arising as a complication of benign esophageal disorders or iatrogenic causes. Prompt diagnosis via multimodality imaging is crucial, with computed tomography being the most sensitive. Management varies based on severity, with a growing trend toward early endoscopic interventions, which result in improved outcomes.

Comparison of i-gel® and LMA® Supreme™ for Facilitating Fiberoptic Endotracheal Intubation: A Prospective Randomized Trial

Supraglottic airway (SGA) is an alternative to endotracheal intubation, however endotracheal intubation is often essential. One method to convert from an SGA to an endotracheal tube (ETT) is utilizing the SGA as a conduit for fiberoptic-guided advancement of an Aintree catheter (airway exchange catheter), and exchange of the SGA for an ETT. In this prospective randomized study, we compared two SGA devices in facilitating this exchange. Subjects were randomized to receive either the i-gel® or LMA® Supreme™ SGA. The SGA was placed and an Aintree intubation catheter was inserted through the SGA over a fiberoptic bronchoscope. Next, the SGA was removed, leaving the Aintree within the trachea, and an ETT was placed over the Aintree catheter and advanced into the trachea. The i-gel group exhibited shorter time to successful intubation (median, 191 vs. 434 seconds; P = .002). The i-gel group also had fewer study subjects requiring more than one attempt for successful Aintree placement (33% vs. 75%, P = .02). The i-gel group showed superior laryngeal view score (LVS) (6 vs. 4; P = .003). The i-gel SGA achieved a faster time to successful intubation, higher rate of first attempt Aintree placement, and superior LVS.

Candidate Kidney Protective Strategies for Patients Undergoing Major Abdominal Surgery: A Secondary Analysis of the RELIEF Trial Cohort

BACKGROUND

Acute kidney injury (AKI) is common after major abdominal surgery. Selection of candidate kidney protective strategies for testing in large trials should be based on robust preliminary evidence.

METHODS

A secondary analysis of the Restrictive versus Liberal Fluid Therapy in Major Abdominal Surgery (RELIEF) trial was conducted in adult patients undergoing major abdominal surgery and randomly assigned to a restrictive or liberal perioperative fluid regimen. The primary outcome was maximum AKI stage before hospital discharge. Two multivariable ordinal regression models were developed to test the primary hypothesis that modifiable risk factors associated with increased maximum stage of postoperative AKI could be identified. Each model used a separate approach to variable selection to assess the sensitivity of the findings to modeling approach. For model 1, variable selection was informed by investigator opinion; for model 2, the Least Absolute Shrinkage and Selection Operator (LASSO) technique was used to develop a data-driven model from available variables.

RESULTS

Of 2,444 patients analyzed, stage 1, 2, and 3 AKI occurred in 223 (9.1%), 59 (2.4%), and 36 (1.5%) patients, respectively. In multivariable modeling by model 1, administration of a nonsteroidal anti-inflammatory drug or cyclooxygenase-2 inhibitor, intraoperatively only (odds ratio, 1.77 [99% CI, 1.11 to 2.82]), and preoperative day-of-surgery administration of an angiotensin-converting enzyme inhibitor or angiotensin receptor blocker compared to no regular use (odds ratio, 1.84 [99% CI, 1.15 to 2.94]) were associated with increased odds for greater maximum stage AKI. These results were unchanged in model 2, with the additional finding of an inverse association between nadir hemoglobin concentration on postoperative day 1 and greater maximum stage AKI.

CONCLUSIONS

Avoiding intraoperative nonsteroidal anti-inflammatory drugs or cyclooxygenase-2 inhibitors is a potential strategy to mitigate the risk for postoperative AKI. The findings strengthen the rationale for a clinical trial comprehensively testing the risk-benefit ratio of these drugs in the perioperative period.

EDITOR’S PERSPECTIVE

Effectiveness of Oral Iron Therapy in Anemic Inpatient Pregnant Women: A Single Center Retrospective Cohort Study

Background and aim Oral iron therapy is effective in treating iron deficiency anemia in outpatient pregnant women but has not been studied in inpatient pregnant women. We aimed to evaluate the effect of oral iron therapy versus no therapy during hospitalization on maternal and neonatal outcomes in women with anemia who are hospitalized for pregnancy-related morbidities (i.e., preterm premature rupture of membranes, preterm labor, pre-eclampsia, abnormal placentation, or fetal monitoring). Methods A retrospective, single-center study was conducted in hospitalized pregnant women (2018 to 2020) with inpatient stays of more than three days. The primary outcome was a change in hemoglobin level from admission to delivery in women treated with oral iron compared with those left untreated. Secondary outcomes included the total amount of iron administered before delivery, the time interval from admission to delivery, and neonatal effects. Results Two hundred sixty-three women were admitted, 79 women had anemia, and 29 (36.7%) received at least one dose of oral iron. Baseline patient characteristics were similar between groups. The median (interquartile range) dose of iron in the oral iron group was 1185.0 (477.0, 1874.0) mg. Neither absolute hemoglobin before delivery (control group: 10.0±1.2 g/dL; iron group: 10.1±1.1 g/dL; p=0.774) nor change in hemoglobin from admission to delivery (control group: -0.1±1.1 g/dL vs. iron group: 0.4±1.1 g/dL; p=0.232) differed between groups. Women in the control group had shorter length of stay (LOS) median (IQR) than women in the iron group (control group: 7.1 (5.0, 13.7) days; iron group: 11.4 (7.4, 25.9) days; p=0.03). There were no differences in maternal mode of delivery, though each group had high rates of cesarean delivery (control group: 53.7%; iron group: 72.4%; p=0.181). There were no differences in estimated blood loss at delivery (control group: 559±401; iron group: 662.1±337.4;p=0.264) in either group. Neonatal birthweight (control group: 1.9±0.7 kg; iron group: 1.9±0.7 kg; p=0.901), birth hemoglobin (control group: 16.3±2.2 g/dL; iron group: 16±2.2 g/dL; p=0.569), neonatal intensive care unit (NICU) admission (control group: 93.3%; iron group: 84.8%;p=0.272 ), or neonatal death (control group: 8.9%; iron group: 3%; p=0.394) were not different between groups. Conclusions Oral iron administered to anemic inpatient pregnant women was not associated with higher hemoglobin concentrations before delivery. Lack of standardized iron regimens and short hospital stays may contribute to the inefficacy of oral iron for this inpatient pregnant population. The small sample size and retrospective nature of this study are limiting factors in drawing conclusive evidence from this study.

Recurrent delirium episodes within the intensive care unit: Incidence and associated factors

PURPOSE

Describe the incidence and factors associated with recurrent delirium in the intensive care unit (ICU).

MATERIALS AND METHODS

Retrospective study of ICU patients diagnosed with delirium. Delirium clearance defined as 48 h of negative delirium assessments following initial episode and recurrent delirium as any positive delirium assessment following clearance. Multivariable logistic regression model assessed independent association of patient and hospital factors on development of recurrent delirium, adjusting for pre-defined covariates.

RESULTS

Among 8591 ICU admissions identified with delirium, 1067 (12.4%) had recurrent symptoms. Factors associated with increased odds of recurrent delirium were age (nonlinear; p = 0.02), shock (OR 1.45, 95% CI [1.20, 1.75]), admission to medical (OR 3.25, 95% CI [2.42, 4.37]), surgical (OR 3.00, 95% CI [2.21, 4.06]), or trauma (OR 2.17, 95% CI [1.58, 3.00]) ICU vs. cardiovascular ICU, increased duration of mechanical ventilation (OR 2.43, 95% CI [2.22, 2.65]), propofol use (OR 1.35, 95% CI [1.02, 1.80]), and antipsychotic medications (haloperidol OR 1.53, 95% CI [1.26, 1.86]; quetiapine OR 2.45, 95% CI [1.98, 3.02]; and olanzapine OR 1.54, 95% CI [1.25, 1.88]).

CONCLUSIONS

Over 10% of delirious ICU patients had recurrent symptoms. Factors associated with recurrence included age, duration of mechanical ventilation and medication exposure.

CLINICAL TRIAL NUMBER

Not applicable.

Artificial intelligence in cardiac computed tomography

Artificial Intelligence (AI) is a broad discipline of computer science and engineering. Modern application of AI encompasses intelligent models and algorithms for automated data analysis and processing, data generation, and prediction with applications in visual perception, speech understanding, and language translation. AI in healthcare uses machine learning (ML) and other predictive analytical techniques to help sort through vast amounts of data and generate outputs that aid in diagnosis, clinical decision support, workflow automation, and prognostication. Coronary computed tomography angiography (CCTA) is an ideal union for these applications due to vast amounts of data generation and analysis during cardiac segmentation, coronary calcium scoring, plaque quantification, adipose tissue quantification, peri-operative planning, fractional flow reserve quantification, and cardiac event prediction. In the past 5 years, there has been an exponential increase in the number of studies exploring the use of AI for cardiac computed tomography (CT) image acquisition, de-noising, analysis, and prognosis. Beyond image processing, AI has also been applied to improve the imaging workflow in areas such as patient scheduling, urgent result notification, report generation, and report communication. In this review, we discuss algorithms applicable to AI and radiomic analysis; we then present a summary of current and emerging clinical applications of AI in cardiac CT. We conclude with AI's advantages and limitations in this new field.

Predictors of non-calcified plaque presence and future adverse cardiovascular events in symptomatic rural Appalachian patients with a zero coronary artery calcium score

BACKGROUND

Coronary artery calcium (CAC) scoring is a proven predictor for future adverse cardiovascular events (CVE) in asymptomatic individuals. Data is emerging regarding the usefulness of non-calcified plaque (NCP) assessment on cardiac computed tomography (CCT) angiography in symptomatic patients with a zero CAC score for further risk assessment.

METHODS

A retrospective review from January 2019 to January 2022 of 696 symptomatic patients with no known CAD and a zero CAC score identified 181 patients with NCP and 515 patients without NCP by a visual assessment on CCT angiography. The primary endpoint was to identify predictors for NCP presence and adverse CVEs (death, myocardial infarction, or cerebrovascular accident) within two years.

RESULTS

Based on logistic regression, age (OR 1.039, 95% CI [1.020-1.058], p ​< ​0.001), diabetes mellitus (OR 2.192, 95% CI [1.307-3.676], p ​< ​0.003), tobacco use (OR 1.748, 95% CI [1.157-2.643], p ​< ​0.008), low-density lipoprotein cholesterol level (OR 1.009, 95% CI [1.003-1.015], p ​< ​0.002), and hypertension (OR 1.613, 95% CI [1.024-2.540], p ​< ​0.039) were found to be predictors of NCP presence. NCP patients had a higher pretest probability for CAD using the Morise risk score (p ​< ​0.001∗), with NCP detection increasing as pretest probability increased from low to high (OR 55.79, 95% CI [24.26-128.26], p ​< ​0.001∗). 457 patients (66%) reached a full two-year period after CCT angiography completion, with NCP patients noted to have shorter follow-up times and higher rates of elective coronary angiography, intervention, and CVEs. The presence of NCP (aOR 2.178, 95% CI [1.025-4.627], p ​< ​0.043) was identified as an independent predictor for future adverse CVEs when adjusted for diabetes mellitus, age, and hypertension.

CONCLUSION

NCP was identified at high rates (26%) in our symptomatic Appalachian population with no known CAD and a zero CAC score. NCP was identified as an independent predictor of future adverse CVEs within two years.

A pilot study to determine the incidence, type, and severity of non-routine events in neonates undergoing gastrostomy tube placement

BACKGROUND

Non-routine events (NRE) are defined as any suboptimal occurrences in a process being measured in the opinion of the reporter and comes from the field of human factors engineering. These typically occur well up-stream of an adverse event and NRE measurement has not been applied to the complex context of neonatal surgery. We sought to apply this novel safety event measurement methodology to neonates in the NICU undergoing gastrostomy tube placement.

METHODS

A prospective pilot study was conducted between November 2016 and August 2020 in the Level IV NICU and the pediatric operating rooms of an urban academic children's hospital to determine the incidence, severity, impact, and contributory factors of clinician-reported non-routine events (NREs, i.e., deviations from optimal care) and 30-day NSQIP occurrences in neonates receiving a G-tube.

RESULTS

Clinicians reported at least one NRE in 32 of 36 (89%) G-tube cases, averaging 3.0 (Standard deviation: 2.5) NRE reports per case. NSQIP-P review identified 7 cases (19%) with NSQIP-P occurrences and each of these cases had multiple reported NREs. One case in which NREs were not reported was without NSQIP-P occurrences. The odds ratio of having a NSQIP-P occurrence with the presence of an NRE was 0.695 (95% CI 0.06-17.04).

CONCLUSION

Despite being considered a "simple" operation, >80% of neonatal G-tube placement operations had at least one reported NRE by an operative team member. In this pilot study, NRE occurrence was not significantly associated with the subsequent reporting of an NSQIP-P occurrence. Understanding contributory factors of NREs that occur in neonatal surgery may promote surgical safety efforts and should be evaluated in larger and more diverse populations.

LEVEL OF EVIDENCE

IV.

Erector Spinae Plane Catheter Analgesia in Minimally Invasive Mitral Valve Surgery: A Retrospective Case-Control Study for Inclusion in an Enhanced Recovery Program

Background. A retrospective case-control study was conducted to assess the feasibility of erector spinae plane (ESP) block as part of a multimodal enhanced recovery program for patients undergoing minimally invasive mitral valve replacement surgery. Methods. This retrospective analysis was conducted at a single center between January and August 2019. 61 patients were included; 23 received ESP and 38 did not. Erector spinae catheters (ESCs) were placed preoperatively, using a loading dose of 30 mL .5% ropivacaine, followed by an infusion of .2% ropivacaine at 10 mL/h throughout the study period. Primary outcome was 48-hour opioid consumption. Secondary outcomes included intraoperative morphine equivalents, extubation within 24 hours, reintubation, ICU length of stay and hospital length of stay and 30-day mortality. Results. Median [inter-quartile range] of the postoperative morphine milligram equivalents (MMEs) in the first 48 hours was 70[45-121] MMEs in the ESC) group, and 109[70-148] MMEs in the no ESC group (P-value = .16). No significant difference was observed in intraoperative morphine equivalents, extubation within 24 hours or ICU length of stay. The ESC group had shorter hospital length of stay (6.0 vs 7.0 days, P-value = .043). Conclusion. This study found a statistically insignificant, though potentially clinically significant reduction in postoperative opioid consumption. A reduced hospital length of stay as well as an acceptable safety profile was also observed in the ESC group. An adequately powered, prospective trial is warranted to accurately assess the potential role for ESP catheters for patients undergoing minimally invasive mitral valve surgery.

Garden-Hose Mitral Regurgitation: A Variant That Can Result in Underestimation of Severity: A Multimodality Imaging Case Study

The quantitative assessment of mitral regurgitation (MR) by echocardiography has limitations. Cardiac magnetic resonance (CMR) imaging has an emerging role in the quantitation of MR, and preliminary studies indicate that CMR assessment may more accurately quantify MR and better correlate with postsurgical left ventricular reverse remodeling. The authors here report a case of MR in which multimodality imaging with CMR and transesophageal echocardiography was crucial in accurately diagnosing the severity of MR when transthoracic and provocative supine bike echocardiography underestimated the degree of MR in a unique variant known as "garden-hose" MR.

Sources of Variation in Anesthetic Drug Costs

BACKGROUND

Increasing attention has been focused on health care expenditures, which include anesthetic-related drug costs. Using data from 2 large academic medical centers, we sought to identify significant contributors to anesthetic drug cost variation.

METHODS

Using anesthesia information management systems, we calculated volatile and intravenous drug costs for 8 types of inpatient surgical procedures performed from July 1, 2009, to December 31, 2011. For each case, we determined patient age, American Society of Anesthesiologists (ASA) physical status, gender, institution, case duration, in-room provider, and attending anesthesiologist. These variables were then entered into 2 fixed-effects linear regression models, both with logarithmically transformed case cost as the outcome variable. The first model included duration, attending anesthesiologist, patient age, ASA physical status, and patient gender as independent variables. The second model included case type, institution, patient age, ASA physical status, and patient gender as independent variables. When all variables were entered into 1 model, redundancy analyses showed that case type was highly correlated (R = 0.92) with the other variables in the model. More specifically, a model that included case type was no better at predicting cost than a model without the variable, as long as that model contained the combination of attending anesthesiologist and case duration. Therefore, because we were interested in determining the effect both variables had on cost, 2 models were created instead of 1. The average change in cost resulting from each variable compared to the average cost of the reference category was calculated by first exponentiating the β coefficient and subtracting 1 to get the percent difference in cost. We then multiplied that value by the mean cost of the associated reference group.

RESULTS

A total of 5504 records were identified, of which 4856 were analyzed. The median anesthetic drug cost was $38.45 (25th percentile = $23.23, 75th percentile = $63.82). The majority of the variation was not described by our models-35.2% was explained in the model containing case duration, and 32.3% was explained in the model containing case type. However, the largest sources of variation our models identified were attending anesthesiologist, case type, and procedure duration. With all else held constant, the average change in cost between attending anesthesiologists ranged from a cost decrease of $41.25 to a cost increase of $95.67 (10th percentile = -$19.96, 90th percentile = +$20.20) when compared to the provider with the median value for mean cost per case. The average change in cost between institutions was significant but minor ($5.73).

CONCLUSIONS

The majority of the variation was not described by the models, possibly indicating high per-case random variation. The largest sources of variation identified by our models included attending anesthesiologist, procedure type, and case duration. The difference in cost between institutions was statistically significant but was minor. While many prior studies have found significant savings resulting from cost-reducing interventions, our findings suggest that because the overall cost of anesthetic drugs was small, the savings resulting from interventions focused on the clinical practice of attending anesthesiologists may be negligible, especially in institutions where access to more expensive drugs is already limited. Thus, cost-saving efforts may be better focused elsewhere.

Beta-lactam carryover in arterial and central venous catheters is negligible

BACKGROUND

Therapeutic drug monitoring is used for aminoglycosides and vancomycin, and has been proposed for β-lactam antibiotics. Clinical blood samples in the ICU are often obtained via an existing vascular catheter rather than fresh needle phlebotomy. If antibiotics had previously been infused through a vascular catheter then used for blood sampling, carryover of antibiotic from the infusion to the sample might result in misleading assessments of target attainment. To address this concern we conducted a series of in vitro measurements of carryover for three commonly used antibiotics.

METHODS

We infused piperacillin-tazobactam, meropenem, and cefepime at pharmacologic concentrations through commonly used vascular catheters at our hospital and flushed the catheters. We then aspirated warmed citrated bovine blood through each catheter and measured antibiotic concentrations in each aspirate.

RESULTS

Carryover was below the limits of detection for piperacillin-tazobactam, meropenem, and vancomycin. Cefepime carryover, in contrast, was not negligible and needs to be investigated more fully.

CONCLUSION

Carryover from prior infusions does not appear to jeopardize measurements of piperacillin-tazobactam, meropenem, or vancomycin in commonly used vascular catheters at our institution. Caution in interpreting samples obtained for cefepime measurements appears advised until more data is available.

A Survey of Enhanced Recovery After Surgery Protocols for Cesarean Delivery in Serbia

Enhanced recovery after surgery (ERAS) protocols have been described for patients undergoing colon surgery. Similar protocols for cesarean delivery (CD) have been developed recently. CD is one of the most commonly performed surgical procedures, and adoption of ERAS protocols following CD might benefit patients and the health-care system. We aimed to determine which Serbian hospitals reported ERAS protocols, which elements of ERAS protocols were used in CD patients, and whether ERAS and non-ERAS hospitals differed. The survey was sent to all hospitals with obstetric services and 46 of 49 responded. The questionnaire asked whether ERAS protocols had been formally adopted for surgical patients and about their use in CD patients. Specific questions on elements described in other obstetric ERAS protocols for CD included preoperative patient preparation, type of anesthesia and temperature monitoring used for CD, maternal/neonatal contact, and time to discharge. ERAS protocols are used in 24% of surveyed hospitals, 84% admit the patient the day before elective CDs, 87% use a maternal bowel preparation morning on the day of CD, and 80% administer maternal deep venous thrombosis prophylaxis. Only 33% remove IV in the first postoperative day, and 89% of women do not eat solid food until the day following their CD. Neuraxial anesthesia is used in 46% of elective CDs in ERAS hospitals compared to 9% in non-ERAS hospitals (P < 0.01), and neuraxial narcotics for post CD analgesia are given more often in ERAS hospitals. Thirty-six percentage of ERAS patients are discharged within 3 days vs. none in the non-ERAS group. Few elements of ERAS protocols reported from other centers outside Serbia are employed in Serbian hospitals performing CD. Despite significant changes that have been made recently in CD care, enhanced recovery after CD could be significantly improved in Serbian hospitals.

Therapeutic drug monitoring of piperacillin and tazobactam by RP-HPLC of residual blood specimens

BACKGROUND

Sepsis is a common diagnosis in critical care with inpatient mortality rates up to 50%. Sepsis care is organized around source control, antibiotics, and supportive care. Drug disposition is deranged by changes in volume of distribution and regional blood flow, as well as multiple organ failure. Thus, assuring that each patient with sepsis attains pharmacokinetic targets is challenging. There is currently no commercially available FDA-approved assay to measure piperacillin-tazobactam, very commonly used as a beta-lactam/beta-lactamase inhibitor combination antibiotic in the intensive care unit (ICU).

METHODS

Samples were prepared by ultrafiltration of plasma collected in lithium heparin Vacutainers. Separation was achieved by gradient elution on a C-18 column followed by UV detection at 214 nm. The method is validated in residual blood samples allowing investigators to exploit a waste product to develop insight into beta-lactam pharmacokinetics in the ICU.

RESULTS

Accuracy and precision were within the 25% CLIA error standard for other antibiotic assays. Free piperacillin concentrations were also in good agreement with total piperacillin concentrations measured in the same plasma by an assay in clinical use outside the United States.

CONCLUSION

We describe a method for measuring piperacillin and tazobactam that meets clinical validation standards. Quick turnaround time and excellent accuracy on a low-cost platform make this method more than adequate for use as a routine therapeutic drug monitoring tool.

Chronic Pain Without Clear Etiology in Low- and Middle-Income Countries: A Narrative Review

Globally, 8 of the top 12 disabling conditions are related either to chronic pain or to the psychological conditions strongly associated with persistent pain. In this narrative review, we explore the demographic and psychosocial associations with chronic pain exclusively from low- and middle-income countries (LMICs) and compare them with current global data. One hundred nineteen publications in 28 LMICs were identified for review; associations with depression, anxiety, posttraumatic stress, insomnia, disability, gender, age, rural/urban location, education level, income, and additional sites of pain were analyzed for each type of chronic pain without clear etiology. Of the 119 publications reviewed, pain was described in association with disability in 50 publications, female gender in 40 publications, older age in 34 publications, depression in 36 publications, anxiety in 19 publications, and multiple somatic complaints in 13 publications. Women, elderly patients, and workers, especially in low-income and low-education subgroups, were more likely to have pain in multiple sites, mood disorders, and disabilities. In high-income countries, multisite pain without etiology, female gender, and association with mood disturbance and disability may be suggestive of a central sensitization syndrome (CSS). Because each type of prevalent chronic pain without known etiology reviewed had similar associations in LMICs, strategies for assessment and treatment of chronic pain worldwide should consider the possibility of prevalent CSS. Recognition is especially critical in resource-poor areas, because treatment of CSS is vastly different than localized chronic pain.

Development and Patient Satisfaction of a New Telemedicine Service for Pain Management at Massachusetts General Hospital to the Island of Martha's Vineyard

OBJECTIVE

Patients in remote areas lack access to specialist care and pain management services. In order to provide pain management care to patients remote from our center, we created a telemedicine pain clinic (telepain) at Massachusetts General Hospital (MGH) in Boston, MA to extend services to the Island of Martha's Vineyard.

DESIGN

Over 13 months, 238 telepain video clinic evaluations were conducted. A pain physician visited the island 1-2 days per month and performed 121 interventions. Given the novelty of telemedicine clinics, we surveyed patients to gauge satisfaction and identify perceived weaknesses in our approach that could be addressed. Forty-nine consecutive patients answered a 14-question, 5-point balanced Likert-scale survey with 1 (no, definitely not) being most negative and 5 (yes, definitely) being most positive.

SETTING

Patients on Martha's Vineyard referred for pain management consultation services via telemedicine.

PATIENTS

Forty-nine consecutive patients evaluated via telemedicine.

INTERVENTIONS

Likert-scale survey administered.

MEASURES

Questions measured patient impressions of video-based visits with their doctor, convenience of the visit, concerns about privacy, and whether they would recommend such a visit, among other items.

RESULTS

Mean respondent scores for each question were >4.3 indicating a favorable impression of the telepain clinic experience. Lowest mean scores were found when respondents were asked to compare the care they received by telepain versus an in-person visit, or whether they were able to develop a friendly relationship with the doctor.

CONCLUSIONS

The results suggest an overall positive reception of telepain by patients, yet highlight the challenge of building a patient-physician relationship remotely.

Prevalence of chronic pain in low-income and middle-income countries: a systematic review and meta-analysis

BACKGROUND

The global burden of chronic pain and disability could be related to unmet surgical needs. This systematic review and meta-analysis aims to characterise existing data regarding the prevalence and associations of chronic pain in low-income and middle-income countries; this is essential to allow better assessment of its relationship to pre-operative and post-operative pain as emergency and essential surgical services are expanded.

METHODS

According to PRISMA guidelines, we searched PubMed, PsycInfo, and Cochrane registries for articles published before Dec 31, 2013, using the search terms "pain AND (chronic OR persistent) AND (low income countries OR middle income countries OR LMIC OR Africa OR Asia OR Central America OR South America) AND (incidence OR prevalence)." We excluded paediatric populations (aged younger than 18 years) and those with acute pain or pain associated with known trauma, surgery, infection, or medical disorders.

FINDINGS

We identified 122 publications in 28 low-income and middle-income countries for systematic review; 79 surveys from general adult populations, elderly general populations, or workers. The prevalence of any type of chronic pain was 33% (95% CI 26-40) in the general adult population, 56% (36-75) in the general elderly population, and 35% (4-88) in workers; lower back pain was 18% (14-24), 31% (22-41), and 44% (33-55), respectively; headache 39% (27-53), 49% (37-60), and 52% (16-86), respectively; chronic daily headache 5% (3-7), not available, and 12% (8-19), respectively; musculoskeletal pain 26% (19-33), 39% (23-57), and 86% (56-93), respectively; joint pain 14% (11-18), 42% (26-60), and not available, respectively; and widespread pain 14% (9-22), 22% (9-46), and not available, respectively. Due to limited data, meta-analysis could only be done in single populations for some conditions. For general adult populations, chronic migraine was 10% (5-20); chronic tension-type headache was 4% (2-9); chronic pelvic pain or prostatitis was 11% (8-17); and fibromyalgia was 4% (3-7). In elderly general populations, prevalence of temporomandibular disorder was 7% (1-31) and abdominal pain was 6% (1-28). Heterogeneity in prevalence was largely secondary to variable definitions of pain chronicity. Associations were not readily amenable to meta-analysis; yet of the 122 publications, pain was described in association with disability in 50, female sex in 40, older age in 34, depression in 36, anxiety in 19, and multiple somatic complaints in 13.

INTERPRETATION

The prevalence of pain in low-income and middle-income countries is consistent with Global Burden of Disease data, with higher rates in the elderly general population and workers than in the general adult population. 28% of the global burden of disease that could be averted by surgery and safe anaesthesia might also be related to the chronic pain burden. Trauma, cancer, birth complications, congenital defects, and other surgical diseases potentially lead to chronic pain if not treated or if treated inadequately. This meta-analysis shows the range of chronic pain in low-income and middle-income countries, but has fallen short of revealing clear causes for the pain. The demonstration of the prevalence of chronic pain is essential as the era of global surgery begins, to allow benchmarking of this prevalence in the future as emergency and essential surgery services are expanded in low-income and middle-income countries.

FUNDING

None.

Simple kcal/kg formula is comparable to prediction equations for estimating resting energy expenditure in older cognitively impaired long term care residents

OBJECTIVE

Assessment of energy needs is a critical step in developing the nutrition care plan, especially for individuals unable to modulate their own energy intakes. The purpose of this study was to assess precision and accuracy of commonly used prediction equations in comparison to measured resting energy expenditure in a sample of "oldest old" adults residing in long term care (LTC).

SUBJECTS AND DESIGN

Resting energy expenditure (mREE) was measured by indirect calorimetry in 45 residents aged 86.1 ± 7.3 years, and compared to frequently used prediction equations (pREE): Mifflin St.Jeor, Harris Benedict, World Health Organization and Owen. Precision and accuracy were determined by concordance correlation coefficients and number of individuals within ± 10% of mREE. Bland Altman plots with linear dependence trends were constructed to visualize agreement. To complete analyses, the common 25 kcal/kg formula was assessed and alternative formulas were determined for best fit by regressing adjusted mREE on body weight.

RESULTS

mREE averaged 976.2 ± 190.3 kcal/day for females and 1260.0 ± 275.9 kcal/d for males. The strength of the relationships between pREE and mREE were only moderate (r = 0.41 - 0.72). In examining linear trends in the Bland Altman plots, significant systematic deviation from mREE was detected for all pREE. Two kcal/kg formulas were generated: 20.6 kcal/kg for females and 22.7 kcal/kg for males, which were not significantly different.

CONCLUSION

None of the prediction equations adequately estimated energy needs in this sample of the "oldest old." A simple formula using 21-23 kcal/kg may be a more practical and reliable method to determine energy needs in the LTC setting.

Meta-analysis of bleeding complications associated with cardiac rhythm device implantation

BACKGROUND

Many patients receiving cardiac rhythm devices have conditions requiring antiplatelet (AP) and/or anticoagulant (AC) therapy. Current guidelines recommend a heparin-bridging strategy (HBS) for anticoagulated patients with moderate/high risk for thrombosis. Several studies reported lower bleeding risk with continued oral anticoagulation rather than HBS. The best strategy for perioperative management of patients on AP therapy is less clear. The present study was designed as a meta-analysis of device implantation-associated bleeding complications using different AC/AP therapies.

METHODS AND RESULTS

PubMed and Cochrane Database searches identified articles based on design, outcomes, and available data. Device recipients were grouped as follows: no therapy, aspirin only, AC held, AC continued, dual AP, and HBS. The primary outcome was defined as a bleeding complication including hematoma, transfusion, or prolonged hospital stay. Thirteen articles were identified for analysis including 5978 patients. The combined incidence of bleeding complications was 274 of 5978 (4.6%), ranging from 2.2% (no therapy) to 14.6% (HBS). The estimated odds of bleeding were increased by 8.3 (95% CI, 5.5-12.9) times in the HBS group, 5.0 (95% CI, 3.0-8.3) for dual AP therapy, 1.7 (95% CI, 1.0-3.1) for AC held, 1.6 (95% CI, 0.9-2.6) for AC continued, and 1.5 (95% CI, 0.9-2.3) for aspirin only relative to the no therapy group. HBS significantly increased bleeding events compared with holding or continuing AC. Continuing AC did not increase bleeding events compared with no therapy.

CONCLUSIONS

Continuing AC appears safer than HBS for device implantation. Dual AP therapy but not continuing AC carries a significant risk of bleeding.

Assessing the functional coherence of gene sets with metrics based on the Gene Ontology graph

MOTIVATION

The results of initial analyses for many high-throughput technologies commonly take the form of gene or protein sets, and one of the ensuing tasks is to evaluate the functional coherence of these sets. The study of gene set function most commonly makes use of controlled vocabulary in the form of ontology annotations. For a given gene set, the statistical significance of observing these annotations or 'enrichment' may be tested using a number of methods. Instead of testing for significance of individual terms, this study is concerned with the task of assessing the global functional coherence of gene sets, for which novel metrics and statistical methods have been devised.

RESULTS

The metrics of this study are based on the topological properties of graphs comprised of genes and their Gene Ontology annotations. A novel aspect of these methods is that both the enrichment of annotations and the relationships among annotations are considered when determining the significance of functional coherence. We applied our methods to perform analyses on an existing database and on microarray experimental results. Here, we demonstrated that our approach is highly discriminative in terms of differentiating coherent gene sets from random ones and that it provides biologically sensible evaluations in microarray analysis. We further used examples to show the utility of graph visualization as a tool for studying the functional coherence of gene sets.

AVAILABILITY

The implementation is provided as a freely accessible web application at: http://projects.dbbe.musc.edu/gosteiner. Additionally, the source code written in the Python programming language, is available under the General Public License of the Free Software Foundation.

SUPPLEMENTARY INFORMATION

Supplementary data are available at Bioinformatics online.

Transposed basilic vein versus polytetrafluorethylene for brachial-axillary arteriovenous fistulas

BACKGROUND

Both transposed basilic vein (BV) and polytetrafluorethylene (PTFE) upper arm arteriovenous fistulas (AVF) are common angioaccess operations. To evaluate the patency and complication rates after AVF, a concurrent series of patients was reviewed.

METHODS

Ninety-eight patients underwent brachial artery to axillary vein AVF: 30 BV and 68 PTFE. The PTFE grafts were performed in the standard fashion, whereas the basilic veins were translocated subcutaneously to the brachial artery.

RESULTS

Risk factors were similar between the two groups. Basilic vein AVF had better patency at 24 months (70% BV versus 46% PTFE, P = 0.023). The dialysis access complications were higher in the BV group (20%) versus PTFE (5%), but the PTFE group had a higher infection rate (10%) than BV (0%).

CONCLUSIONS

The primary and secondary patency rates were superior in the BV AVFs. The BV AVF preserves the venous outflow tract after AVF thrombosis for a future PTFE AVF operation.

Fine structure analysis of the Chinese hamster AS gene encoding asparagine synthetase

Overlapping cDNAs for Chinese hamster ovary (CHO) asparagine synthetase (AS) were isolated from a library prepared from an AS-overproducing cell line. The sequence was determined and shown to contain an open reading frame encoding a protein of Mr 64,300. The predicted amino acid sequence for the CHO AS enzyme was compared to that of the human AS enzyme and found to be 95% homologous. A potential glutamine amide transfer domain, with sequence similarity to amidotransferases from bacteria and yeast, was identified in the N-terminal portion of the protein. The cDNAs were used to screen a library of phage containing wild type CHO DNA and the genomic AS sequences were detected on three overlapping phages. Determination of the fine structural organization showed that the CHO AS gene spanned 19 kilobases and was composed of 12 exons, three of which contained the glutamine amidotransferase domain. The 5' flanking sequences were highly G + C-rich and, like other housekeeping genes, lacked TATA and CAAT boxes.