Patrick J. McCormick

EHDViz: clinical dashboard development using open-source technologies

Objective To design, develop and prototype clinical dashboards to integrate high-frequency health and wellness data streams using interactive and real-time data visualisation and analytics modalities. Materials and methods We developed a clinical dashboard development framework called electronic healthcare data visualization (EHDViz) toolkit for generating web-based, real-time clinical dashboards for visualising heterogeneous biomedical, healthcare and wellness data. The EHDViz is an extensible toolkit that uses R packages for data management, normalisation and producing high-quality visualisations over the web using R/Shiny web server architecture. We have developed use cases to illustrate utility of EHDViz in different scenarios of clinical and wellness setting as a visualisation aid for improving healthcare delivery. Results Using EHDViz, we prototyped clinical dashboards to demonstrate the contextual versatility of EHDViz toolkit. An outpatient cohort was used to visualise population health management tasks (n=14 221), and an inpatient cohort was used to visualise real-time acuity risk in a clinical unit (n=445), and a quantified-self example using wellness data from a fitness activity monitor worn by a single individual was also discussed (n-of-1). The back-end system retrieves relevant data from data source, populates the main panel of the application and integrates user-defined data features in real-time and renders output using modern web browsers. The visualisation elements can be customised using health features, disease names, procedure names or medical codes to populate the visualisations. The source code of EHDViz and various prototypes developed using EHDViz are available in the public domain at http://ehdviz.dudleylab.org. Conclusions Collaborative data visualisations, wellness trend predictions, risk estimation, proactive acuity status monitoring and knowledge of complex disease indicators are essential components of implementing data-driven precision medicine. As an open-source visualisation framework capable of integrating health assessment, EHDViz aims to be a valuable toolkit for rapid design, development and implementation of scalable clinical data visualisation dashboards.

Effectiveness of an Electronic Alert for Hypotension and Low Bispectral Index on 90-day Postoperative Mortality: A Prospective, Randomized Trial.

Background:We tested the hypothesis that an electronic alert for a “double low” of mean arterial pressure less than 75 mmHg and a bispectral index less than 45 reduces the primary outcome of 90-day mortality. Methods:Adults having noncardiac surgery were randomized to receive either intraoperative alerts for double-low events or no alerts. Anesthesiologists were not blinded and not required to alter care based upon the alerts. The primary outcome was all-cause 90-day mortality. Results:Patients (20,239) were randomized over 33 months, and 19,092 were analyzed. After adjusting for age, comorbidities, and perioperative factors, patients with more than 60 min of cumulative double-low time were twice as likely to die (hazard ratio, 1.99; 95% CI, 1.2 to 3.2; P = 0.005). The median number of double-low minutes (quartiles) was only slightly lower in the alert arm: 10 (2 to 30) versus 12 (2 to 34) min. Ninety-day mortality was 135 (1.4%) in the alert arm and 123 (1.3%) in the control arm. The difference in percent mortality was 0.18% (99% CI, −0.25 to 0.61). Conclusions:Ninety-day mortality was not significantly lower in patients cared for by anesthesiologists who received automated alerts to double-low states. Prolonged cumulative double-low conditions were strongly associated with mortality.

Intraoperative arterial blood pressure lability is associated with improved 30 day survival

BACKGROUND Arterial blood pressure lability, defined as rapid changes in arterial blood pressure, occurs commonly during anaesthesia. It is believed that hypertensive patients exhibit more lability during surgery and that lability is associated with poorer outcomes. Neither association has been rigorously tested. We hypothesized that hypertensive patients have more blood pressure lability and that increased lability is associated with increased 30 day mortality. METHODS This was a retrospective single-centre study of surgical patients from July 2008 to December 2012. Intraoperative data were extracted from the electronic anaesthesia record. Lability was calculated as the modulus of the percentage change in mean arterial pressure between consecutive 5 min intervals. The number of episodes of lability >10% was tabulated. Multivariate logistic regression was performed to determine the association between lability and 30 day mortality using derivation and validation cohorts. RESULTS Inclusion criteria were met by 52 919 subjects. Of the derivation cohort, 53% of subjects were hypertensive and 42% used an antihypertensive medication. The median number of episodes of lability >10% was 9 (interquartile range 5-14) per patient. Hypertensive subjects demonstrated more lability than normotensive patients, 10 (5-15) compared with 8 (5-12), P<0.0001. In subjects taking no antihypertensive medication, lability >10% was associated with decreased 30 day mortality, odds ratio (OR) per episode 0.95 [95% confidence interval (CI) 0.92-0.97], P<0.0001. This result was confirmed in the validation cohort, OR 0.96 (95% CI 0.93-0.99), P=0.01, and in hypertensive patients taking no antihypertensive medication, OR 0.96 (95% CI 0.93-0.99), P=0.002. Use of any antihypertensive medication class reduced this effect. CONCLUSIONS Intraoperative arterial blood pressure lability occurs more often in hypertensive patients. Contrary to common belief, increased lability was associated with decreased 30 day mortality.

Elevated Intraoperative Serum Lactate During Craniotomy Is Associated With New Neurological Deficit and Longer Length of Stay.

Background: Hundreds of thousands of craniotomies are performed annually in the United States. During craniotomy, elevated serum lactate is a concerning and not infrequent occurrence. Elevated intraoperative serum lactate may occur as a result of global hypoperfusion or localized intracerebral ischemia from surgical retraction or inadequate blood supply. The distinction between systemic and hypoperfusion confined to the brain is important because the treatment differs. For example, fluid resuscitation may be indicated in the former but not the latter. Methods: To address whether elevated intraoperative serum lactate is associated with hypoperfusion confined to the brain or systemic hypoperfusion, we performed a retrospective cohort study of elective adult (age above 18) craniotomy cases. These included 436 surgeries which were performed at our institution under general anesthesia between May 2011 and August 2013. Results: Elevated intraoperative serum lactate in craniotomy patients is associated with new neurological deficits (odds ratio, 2.11) and longer length of stay (20% less likely to be discharged on a given day). Elevated lactate was not associated with systemic complications such as myocardial infarction or mortality. Conclusions: Our findings highlight the importance of conducting a definitive prospective study analyzing the clinical impact and mechanism behind hyperlactatemia in the craniotomy population. Knowledge of the serum lactate level may be of value in guiding intraoperative anesthetic and surgical decision-making.

Postoperative analgesia after minimally invasive thoracoscopy: What should we do?

Many of the thoracic operations that previously required a thoracotomy incision can now be performed with several small incisions and video-assisted thoracic surgery (VATS). Although there have been reports of less pain and less impairment of pulmonary function with VATS compared with thoracotomy, 1 many VATS patients report significant acute and chronic postoperative pain. Treating thoracoscopic pain effectively and minimizing the later development of chronic pain requires familiarity with a wide spectrum of analgesic techniques. An important variable in the analgesic plan for VATS is the likelihood of converting to an open thoracotomy. Conversion may be due to technical difficulties, inadequate lung separation, or bleeding, and may be more likely when the surgeon has less experience with VATS. The likelihood of conversion to an open procedure must be assessed preoperatively. If a VATS procedure is converted to a thoracotomy and analgesia (such as an epidural) is not in place, the patient’s recovery may be impaired. If not wellcontrolled, postoperative thoracic pain can lead to splinting and may impair the patient’s ability to take deep breaths following thoracic surgery. It is difficult to state precisely the incidence of pain following thoracoscopy, as the extent and severity varies according to surgical technique, patient sensitivity, and anesthetic pain management. In a recent survey of Dutch thoracic surgery patients, 47% of the VATS patients reported chronic pain. 2 In an earlier study, the incidence of chronic pain was reported to be 36% in VATS patients undergoing wedge resection. 3 It might seem intuitive that performing the surgery by thoracoscopy, which utilizes small incisions, would lead to less postoperative pain. However, the introduction of trocars during thoracoscopy may injure intercostal nerves, and additional manipulation of these instruments during the surgery may traumatize these nerves further by compression against ribs. 4 If a lobectomy is being performed, an incision will need to be enlarged in order to extract the specimen, and a rib retractor may be required. Also, the duration of the surgery may be greater using VATS. Ipsilateral shoulder pain is a common complaint following VATS, and in one study, it was reported to be chronic in 10% of patients. 5

Delineating the Trajectory of Cognitive Recovery From General Anesthesia in Older Adults: Design and Rationale of the Torie (trajectory of Recovery in the Elderly) Project

BACKGROUND: Mechanistic aspects of cognitive recovery after anesthesia and surgery are not yet well characterized, but may be vital to distinguishing the contributions of anesthesia and surgery in cognitive complications common in the elderly such as delirium and postoperative cognitive dysfunction. This article describes the aims and methodological approach to the ongoing study, Trajectory of Recovery in the Elderly (TORIE), which focuses on the trajectory of cognitive recovery from general anesthesia. METHODS: The study design employs cognitive testing coupled with neuroimaging techniques such as functional magnetic resonance imaging, diffusion tensor imaging, and arterial spin labeling to characterize cognitive recovery from anesthesia and its biological correlates. Applying these techniques to a cohort of age-specified healthy volunteers 40–80 years of age, who are exposed to general anesthesia alone, in the absence of surgery, will assess cognitive and functional neural network recovery after anesthesia. Imaging data are acquired before, during, and immediately after anesthesia, as well as 1 and 7 days after. Detailed cognitive data are captured at the same time points as well as 30 days after anesthesia, and brief cognitive assessments are repeated at 6 and 12 months after anesthesia. RESULTS: The study is underway. Our primary hypothesis is that older adults may require significantly longer to achieve cognitive recovery, measured by Postoperative Quality of Recovery Scale cognitive domain, than younger adults in the immediate postanesthesia period, but all will fully recover to baseline levels within 30 days of anesthesia exposure. Imaging data will address systems neuroscience correlates of cognitive recovery from general anesthesia. CONCLUSIONS: The data acquired in this project will have both clinical and theoretical relevance regardless of the outcome by delineating the mechanism behind short-term recovery across the adult age lifespan, which will have major implications for our understanding of the effects of anesthetic drugs.

A Real-Time Decision Support System for Anesthesiologist End-of-Shift Relief.

A decision support system using recent data about work hours and real-time data about relief events was developed to guide anesthesiologist end-of-shift relief decisions in an effort to promote a relief order that prioritized relief for those who had recently worked later than others. After system implementation, there were fewer deviations from this idealized order of relief, and early relief was more evenly distributed.

The Influence of Positive End-expiratory Pressure on Surgical Field Conditions During Functional Endoscopic Sinus Surgery

BACKGROUND:Functional endoscopic sinus surgery (FESS) is the mainstay of surgical treatment for sinonasal disease. This surgery carries certain risks. Most of these risks relate to the quality of the surgical field. Thus, mechanisms by which the surgical field can be improved are important to study. We sought to determine whether positive end-expiratory pressure (PEEP) had a deleterious effect on the quality of the surgical field in patients undergoing primary FESS. METHODS:Forty-seven patients were randomized to a ventilation strategy using either 5 cm H2O of PEEP or zero added PEEP. The quality of the surgical field was measured every 15 minutes using a validated surgical scoring method. RESULTS:The addition of PEEP did not have any measurable effect on the surgical field scores after onset of surgery (odds ratio [OR] (95% confidence interval [CI]) = 1.06 (0.44–2.58), P = 0.895 for side 1; OR (95% CI) = 0.56 (0.16–1.93), P = 0.356 for side 2). The peak inspiratory pressure did have an effect on surgical grades. Every cm H2O of added pressure over 15 cm H2O total pressure contributing to increased odds of higher surgical field score. For each cm H2O increase in inspiratory pressure above 15cm H2O increased the surgical field score (OR [95% CI] 1.13 [1.04–1.22], P = 0.002). CONCLUSIONS:During FESS surgery if PEEP is added, it is important to keep the mean inspiratory pressure below 15cm H2O to avoid worsening surgical field conditions.

Preventable Anesthesia-Related Adverse Events at a Large Tertiary Care Center

BACKGROUND Anesthesiologists have studied adverse events during anesthesia dating back to the original critical incident studies of the 1970s. Despite improvements, adverse events continue to occur. The purpose of this study was to characterize anesthesia-related adverse events within a single large tertiary care institution and to distinguish preventable adverse events from those that are not preventable. METHODS A retrospective review of all cases referred to the Performance Improvement (PI) Committee at a large academic medical center from 2007 to 2015 was performed. The primary adverse event and underlying cause of the event were determined using a two-reviewer system for each case. Univariate analysis was performed to determine overall characteristics of cases, the underlying causes of adverse events, and whether the event was preventable; p < 0.05 was considered significant. RESULTS A total of 1,424 records were referred to the PI Committee during the study period. After exclusions, 747 cases were included in the final analysis. Respiratory complications (n = 245) were the most frequently reported adverse event type. The most common respiratory events included unplanned reintubations, aspirations, and respiratory arrests. A large proportion of the adverse events (42.8%) may have been preventable. In particular, respiratory, trauma, and medication adverse events were often preventable. CONCLUSION Anesthesia-related adverse events continue to occur even though the field is considered at the forefront of patient safety. Respiratory, trauma, and medication events were often preventable, and these represent areas to allocate resources to improve patient safety and perioperative outcomes.