Proceedings: Sixth International Futures of Aviation Medicine Symposium.

In June 2024, leaders in aviation medicine from across the United States, Canada, and Europe met for the sixth Leonardo Helicopters/Association of Critical Care Transport: The Path to High Reliability Futures of Aviation Medicine Symposium in Miami, FL. The symposia, now held every few years, grew from the 2003 Air Medical Leadership Congress: Setting the Healthcare Agenda for the Air Medical Community. The meetings' goal is to gather leaders to distill, debate, and synthesize the state of the science while identifying, refining, and outlining conditions facilitating favorable evolution in civilian aviation medicine. Structured as thematic panel presentations followed by interactive all-attendee roundtable discussions, the gatherings build and expand an international network of thought leaders and proven doers. Meeting attendees have a common goal-accelerating learning and practice among early and developed systems moving toward a shared worldwide agenda for the future of aviation transport medicine.

The 2022 Certified Transport Registered Nurse Pulse Survey.

OBJECTIVE: The certified transport registered nurse (CTRN) credential independently validates a registered nurse's advanced knowledge, skills, and abilities in critical care ground transport nursing. After multiple years of mostly modest growth, the number of CTRNs surged in 2020 and 2021 and continues to post strong growth into 2022. The aim of the 2022 Certified Transport Registered Nurse Pulse Survey was to better understand the ways in which CTRN-certified registered nurses value this national ground transport specialty credential and gain insight into factors that may have contributed to the recent surge in CTRN certification. METHODS: The Board of Certification for Emergency Nursing e-mailed individuals in its database of CTRN credential holders and invited them to complete an 11-question online survey between March 15 and March 28, 2022. Participation in the survey was voluntary. Sixty-three of 297 verified CTRN holders who received the survey responded for a response rate of 21.2%. The survey instrument included discrete field and open-ended questions. Data were deidentified for analysis, and institutional review board exemption was received. Descriptive statistics were used, and counts and percentages are reported. RESULTS: The highest percentage of respondents (42.9%) have 10 or more years of experience in ground transport nursing, and nearly half (46%) are employed by a stand-alone transport program. Forty-three percent of all respondents reported that ground transport makes up at least 50% of their current role, whereas one third (33.3%) indicated they do ground transport 100% of the time. Critical thinking (87.5%) in the ground transport environment, confidence as a ground transport nurse (87.5%), and a sense of accomplishment and pride (94.6%) were the top 3 perceived benefits of being a CTRN-certified nurse. CONCLUSION: The 2022 CTRN pulse survey identified current CTRN demographics, practice environments, and perceived benefits of the CTRN credential. The findings suggest CTRNs are highly experienced and perceive multiple intrinsic and extrinsic benefits of CTRN certification, many of which are essential to safe, evidence-based nursing practice in the autonomous, complex, and dynamic ground transport environment.

The 2022 Certified Flight Registered Nurse Pulse Survey.

OBJECTIVE: The Certified Flight Registered Nurse (CFRN) credential independently validates a registered nurse's advanced knowledge, skills, and abilities in the unique specialty of flight nursing. Introduced in 1993 and celebrating its 30th anniversary in July 2023, the CFRN is held by over 5,500 registered nurses. The purpose of the 2022 CFRN pulse survey was to better understand the ways CFRN-certified registered nurses value this national flight nursing specialty credential. The CFRN survey is a companion to the 2022 Certified Transport Registered Nurse pulse survey, which focused on the Certified Transport Registered Nurse critical care ground transport nursing credential. METHODS: The Board of Certification for Emergency Nursing e-mailed individuals in its database of CFRN credential holders and asked them to respond to a 14-question online survey between October 17, 2022, and November 8, 2022. Participation in the survey was voluntary. Of the 5,275 verified CFRN holders who received the survey, 992 responded, for a response rate of 18.8%. The survey instrument included discrete field and open-ended questions. Data were deidentified for analysis, and institutional review board exemption was received. Counts and percentages were reported, and descriptive statistics were used. RESULTS: The highest percentage of flight nurses who responded have more than 10 years of experience in flight nursing (35.3%) and are employed by a stand-alone transport program (42.7%). Flight nurses reported they spent a mean of 70% of their work hours transporting via rotor wing aircraft, with a predominantly adult patient population. The top perceived benefits of being a CFRN-certified nurse were a sense of accomplishment and pride (90.7%) followed by flight physiology knowledge (85.4%), flight nursing clinical knowledge (83.4%), and confidence as a flight nurse (80.6%). CONCLUSION: The 2022 CFRN pulse survey identified current CFRN demographics, practice environments including transport percentage by mode and patient population types, and perceived benefits of the CFRN credential. The findings suggest CFRNs are very experienced, provide care for patients across the age continuum, and perceive multiple intrinsic and extrinsic benefits of CFRN certification, all of which are essential to safe, evidence-based advanced nursing practice in the unique, complex, autonomous, and dynamic flight environment.

Interfacility Transport of Critically Ill Patients.

OBJECTIVES: To assess recent advances in interfacility critical care transport. DATA SOURCES: PubMed English language publications plus chapters and professional organization publications. STUDY SELECTION: Manuscripts including practice manuals and standard (1990-2021) focused on interfacility transport of critically ill patients. DATA EXTRACTION: Review of society guidelines, legislative requirements, objective measures of outcomes, and transport practice standards occurred in work groups assessing definitions and foundations of interfacility transport, transport team composition, and transport specific considerations. Qualitative analysis was performed to characterize current science regarding interfacility transport. DATA SYNTHESIS: The Task Force conducted an integrative review of 496 manuscripts combined with 120 from the authors' collections including nonpeer reviewed publications. After title and abstract screening, 40 underwent full-text review, of which 21 remained for qualitative synthesis. CONCLUSIONS: Since 2004, there have been numerous advances in critical care interfacility transport. Clinical deterioration may be mitigated by appropriate patient selection, pretransport optimization, and transport by a well-resourced team and vehicle. There remains a dearth of high-quality controlled studies, but notable advances in monitoring, en route management, transport modality (air vs ground), as well as team composition and training serve as foundations for future inquiry. Guidance from professional organizations remains uncoupled from enforceable regulations, impeding standardization of transport program quality assessment and verification.

Outcomes and risk factors for delayed-onset postoperative respiratory failure: a multi-center case-control study by the University of California Critical Care Research Collaborative (UC3RC).

BACKGROUND: Few interventions are known to reduce the incidence of respiratory failure that occurs following elective surgery (postoperative respiratory failure; PRF). We previously reported risk factors associated with PRF that occurs within the first 5 days after elective surgery (early PRF; E-PRF); however, PRF that occurs six or more days after elective surgery (late PRF; L-PRF) likely represents a different entity. We hypothesized that L-PRF would be associated with worse outcomes and different risk factors than E-PRF. METHODS: This was a retrospective matched case-control study of 59,073 consecutive adult patients admitted for elective non-cardiac and non-pulmonary surgical procedures at one of five University of California academic medical centers between October 2012 and September 2015. We identified patients with L-PRF, confirmed by surgeon and intensivist subject matter expert review, and matched them 1:1 to patients who did not develop PRF (No-PRF) based on hospital, age, and surgical procedure. We then analyzed risk factors and outcomes associated with L-PRF compared to E-PRF and No-PRF. RESULTS: Among 95 patients with L-PRF, 50.5% were female, 71.6% white, 27.4% Hispanic, and 53.7% Medicare recipients; the median age was 63 years (IQR 56, 70). Compared to 95 matched patients with No-PRF and 319 patients who developed E-PRF, L-PRF was associated with higher morbidity and mortality, longer hospital and intensive care unit length of stay, and increased costs. Compared to No-PRF, factors associated with L-PRF included: preexisiting neurologic disease (OR 4.36, 95% CI 1.81-10.46), anesthesia duration per hour (OR 1.22, 95% CI 1.04-1.44), and maximum intraoperative peak inspiratory pressure per cm H20 (OR 1.14, 95% CI 1.06-1.22). CONCLUSIONS: We identified that pre-existing neurologic disease, longer duration of anesthesia, and greater maximum intraoperative peak inspiratory pressures were associated with respiratory failure that developed six or more days after elective surgery in adult patients (L-PRF). Interventions targeting these factors may be worthy of future evaluation.

The Roles and Contributions of Certified Transport Registered Nurses in Critical Care Ground Transport Today.

Registered nurses are core members of critical care ground transport teams because of their education, experience, and scope of practice. Advances in medicine, technology, and equipment, combined with regionalization of specialized care and, most recently, the coronavirus disease 2019 pandemic, necessitate that transport nurses possess specialized knowledge, skills, and abilities. National specialty certification in ground transport nursing via the Certified Transport Registered Nurse (CTRN) offers registered nurses a process to validate their expertise. The most recent transport nursing role delineation study, which was conducted by the Board of Certification for Emergency Nursingin 2019, provided the foundation for the revised CTRN examination content outline, which is now separate from the Certified Flight Registered Nurse (CFRN) content outline. In this article, we provide a brief history of the specialty of ground transport nursing; details on the CTRN examination blueprint; and a composite patient case report to illustrate the ground-specific role, expertise, and contributions of the CTRN in delivering the highest level of patient care during ground transport.

Risk Factors Associated With Early Postoperative Respiratory Failure: A Matched Case-Control Study.

BACKGROUND: Postoperative respiratory failure is the most common serious postoperative pulmonary complication, yet little is known about factors that can reduce its incidence. We sought to elucidate modifiable factors associated with respiratory failure that developed within the first 5 d after an elective operation. MATERIALS AND METHODS: Matched case-control study of adults who had an operation at five academic medical centers between October 1, 2012 and September 30, 2015. Cases were identified using administrative data and confirmed via chart review by critical care clinicians. Controls were matched 1:1 to cases based on hospital, age, and surgical procedure. RESULTS: Our total sample (n = 638) was 56.4% female, 71.3% white, and had a median age of 62 y (interquartile range 51, 70). Factors associated with early postoperative respiratory failure included male gender (odds ratio [OR] 1.72, 95% confidence interval [CI] 1.12-2.63), American Society of Anesthesiologists class III or greater (OR 2.85, 95% CI 1.74-4.66), greater number of preexisting comorbidities (OR 1.14, 95% CI 1.004-1.30), increased operative duration (OR 1.14, 95% CI 1.06-1.22), increased intraoperative positive end-expiratory pressure (OR 1.23, 95% CI 1.13-1.35) and tidal volume (OR 1.13, 95% CI 1.004-1.27), and greater net fluid balance at 24 h (OR 1.17, 95% CI 1.07-1.28). CONCLUSIONS: We found greater intraoperative ventilator volume and pressure and 24-h fluid balance to be potentially modifiable factors associated with developing early postoperative respiratory failure. Further studies are warranted to independently verify these risk factors, explore their role in development of early postoperative respiratory failure, and potentially evaluate targeted interventions.

Comparing demographics, treatments, and outcomes of patients with COVID-19 lesions versus hospital-acquired pressure ulcers/injuries during the first year of COVID-19.

BACKGROUND: As COVID-19 has emerged as a pandemic virus, multiple reports have surfaced to describe skin lesions that occur either associated with the virus or due to treatment. OBJECTIVE: To compare patient demographics, treatments, and outcomes in COVID-19 symptomatic patients who developed skin lesions (COVID-19 or hospital-acquired pressure ulcer/injury [HAPU/I]) during the first year of the pandemic. METHODS: A retrospective chart review was conducted on COVID-positive symptomatic patients admitted from March 1, 2020, through March 1, 2021. The authors analyzed the difference in patient demographics, patient skin tones, treatments, hospital length of stay (LOS), intensive care unit (ICU) LOS, death, and discharge disposition for those with COVID-19 lesions compared to those who developed HAPU/Is. RESULTS: Of those who developed lesions, 2.3% developed COVID-19 lesions and 7.2% developed HAPU/Is. Patients with COVID-19 lesions were more likely to be male (64%), younger (median age 60), and had a higher BMI (30) than patients with no wounds and patients with HAPU/I. CONCLUSION: This study advances the knowledge of the patient demographics and treatments that may contribute to identifying the new phenomenon of COVID lesions and how they differ from HAPU/Is.

Noninvasive vs invasive respiratory support for patients with acute hypoxemic respiratory failure.

BACKGROUND: Noninvasive respiratory support modalities are common alternatives to mechanical ventilation in acute hypoxemic respiratory failure. However, studies historically compare noninvasive respiratory support to conventional oxygen rather than mechanical ventilation. In this study, we compared outcomes in patients with acute hypoxemic respiratory failure treated initially with noninvasive respiratory support to patients treated initially with invasive mechanical ventilation. METHODS: This is a retrospective observational cohort study between January 1, 2018 and December 31, 2019 at a large healthcare network in the United States. We used a validated phenotyping algorithm to classify adult patients (≥18 years) with eligible International Classification of Diseases codes into two cohorts: those treated initially with noninvasive respiratory support or those treated invasive mechanical ventilation only. The primary outcome was time-to-in-hospital death analyzed using an inverse probability of treatment weighted Cox model adjusted for potential confounders. Secondary outcomes included time-to-hospital discharge alive. A secondary analysis was conducted to examine potential differences between noninvasive positive pressure ventilation and nasal high flow. RESULTS: During the study period, 3177 patients met inclusion criteria (40% invasive mechanical ventilation, 60% noninvasive respiratory support). Initial noninvasive respiratory support was not associated with a decreased hazard of in-hospital death (HR: 0.65, 95% CI: 0.35-1.2), but was associated with an increased hazard of discharge alive (HR: 2.26, 95% CI: 1.92-2.67). In-hospital death varied between the nasal high flow (HR 3.27, 95% CI: 1.43-7.45) and noninvasive positive pressure ventilation (HR 0.52, 95% CI 0.25-1.07), but both were associated with increased likelihood of discharge alive (nasal high flow HR 2.12, 95 CI: 1.25-3.57; noninvasive positive pressure ventilation HR 2.29, 95% CI: 1.92-2.74). CONCLUSIONS: These data show that noninvasive respiratory support is not associated with reduced hazards of in-hospital death but is associated with hospital discharge alive.

Endobronchial Phenylephrine in Airway Bleeding During Bronchoscopy Does not Cause Hypertension: A Retrospective Observational Study.

BACKGROUND: Bleeding is a known complication during bronchoscopy, with increased incidence in patients undergoing a more invasive procedure. Phenylephrine is a potent vasoconstrictor that can control airway bleeding when applied topically and has been used as an alternative to epinephrine. The clinical effects of endobronchial phenylephrine on systemic vasoconstriction have not been clearly evaluated. Here, we compared the effects of endobronchial phenylephrine versus cold saline on systemic blood pressure. METHODS: In all, 160 patients who underwent bronchoscopy and received either endobronchial phenylephrine or cold saline from July 1, 2017 to June 30, 2022 were included in this retrospective observational study. Intra-procedural blood pressure absolute and percent changes were measured and compared between the 2 groups. RESULTS: There were no observed statistical differences in blood pressure changes between groups. The median absolute change between the median and the maximum intra-procedural systolic blood pressure in the cold saline group was 29 mm Hg (IQR 19 to 41) compared with 31.8 mm Hg (IQR 18 to 45.5) in the phenylephrine group. The corresponding median percent changes in SBP were 33.6 % (IQR 18.8 to 39.4) and 28% (IQR 16.8 to 43.5) for the cold saline and phenylephrine groups, respectively. Similarly, there were no statistically significant differences in diastolic and mean arterial blood pressure changes between both groups. CONCLUSIONS: We found no significant differences in median intra-procedural systemic blood pressure changes comparing patients who received endobronchial cold saline to those receiving phenylephrine. Overall, this argues for the vascular and systemic safety of phenylephrine for airway bleeding as a reasonable alternative to epinephrine.

Early Mobility Index and Patient Outcomes: A Retrospective Study in Multiple Intensive Care Units.

BACKGROUND: Early mobility interventions in intensive care units (ICUs) are safe and improve outcomes in subsets of critically ill adults. However, implementation varies, and the optimal mobility dose remains unclear. OBJECTIVE: To test for associations between daily dose of out-of-bed mobility and patient outcomes in different ICUs. METHODS: In this retrospective cohort study of electronic records from 7 adult ICUs in an academic quarternary hospital, multivariable linear regression was used to examine the effects of out-of-bed events per mobility-eligible day on mechanical ventilation duration and length of ICU and hospital stays. RESULTS: In total, 8609 adults hospitalized in ICUs from 2015 through 2018 were included. Patients were mobilized out of bed on 46.5% of ICU days and were eligible for mobility interventions on a median (IQR) of 2.0 (1-3) of 2.7 (2-9) ICU days. Median (IQR) out-of-bed events per mobility-eligible day were 0.5 (0-1.2) among all patients. For every unit increase in out-of-bed events per mobility-eligible day before extubation, mechanical ventilation duration decreased by 10% (adjusted coefficient [95% CI], -0.10 [-0.18 to -0.01]). Daily mobility increased ICU stays by 4% (adjusted coefficient [95% CI], 0.04 [0.03-0.06]) and decreased hospital stays by 5% (adjusted coefficient [95% CI], -0.05 [-0.07 to -0.03]). Effect sizes differed among ICUs. CONCLUSIONS: More daily out-of-bed mobility for ICU patients was associated with shorter mechanical ventilation duration and hospital stays, suggesting a dose-response relationship between daily mobility and patient outcomes. However, relationships differed across ICU subpopulations.

Using the ROX Index to Predict Treatment Outcome for High-Flow Nasal Cannula and/or Noninvasive Ventilation in Patients With COPD Exacerbations.

BACKGROUND: The ratio of oxygen saturation index (ROX index; or SpO2 /FIO2 /breathing frequency) has been shown to predict risk of intubation after high-flow nasal cannula (HFNC) support among adults with acute hypoxemic respiratory failure primarily due to pneumonia. However, its predictive value for other subtypes of respiratory failure is unknown. This study investigated whether the ROX index predicts liberation from HFNC or noninvasive ventilation (NIV), intubation with mechanical ventilation, or death in adults admitted for respiratory failure due to an exacerbation of COPD. METHODS: We performed a retrospective study of 260 adults hospitalized with a COPD exacerbation and treated with HFNC and/or NIV (continuous or bi-level). ROX index scores were collected at treatment initiation and predefined time intervals throughout HFNC and/or NIV treatment or until the subject was intubated or died. A ROX index score of ≥ 4.88 was applied to the cohort to determine if the same score would perform similarly in this different cohort. Accuracy of the ROX index was determined by calculating the area under the receiver operator curve. RESULTS: A total of 47 subjects (18%) required invasive mechanical ventilation or died while on HFNC/NIV. The ROX index at treatment initiation, 1 h, and 6 h demonstrated the best prediction accuracy for avoidance of invasive mechanical ventilation or death (area under the receiver operator curve 0.73 [95% CI 0.66-0.80], 0.72 [95% CI 0.65-0.79], and 0.72 [95% CI 0.63-0.82], respectively). The optimal cutoff value for sensitivity (Sn) and specificity (Sp) was a ROX index score > 6.88 (sensitivity 62%, specificity 57%). CONCLUSIONS: The ROX index applied to adults with COPD exacerbations treated with HFNC and/or NIV required higher scores to achieve similar prediction of low risk of treatment failure when compared to subjects with hypoxemic respiratory failure/pneumonia. ROX scores < 4.88 did not accurately predict intubation or death.

A ten-year retrospective California Poison Control System experience with possible amatoxin mushroom calls.

INTRODUCTION: Mushrooms containing amatoxin are found worldwide and represent a challenging poisoning for the clinician and consulting poison center. This study evaluates the experience of a large poison system with possible amatoxin-containing mushroom ingestion calls. METHODS: A 10-year retrospective review of the California Poison Control System database was performed for amatoxin mushroom ingestion calls resulting in hospitalization. Cases found were abstracted and data statistically analyzed for association with a composite endpoint of death, liver transplant, and/or the need for dialysis. RESULTS: Amatoxin-containing mushroom calls are infrequent with the vast majority (98.4 percent) coming from Northern California during the rainier first and fourth quarters (October through March) of the year. Elevated initial aminotransferase activities and international normalized ratios were predictive of the composite negative outcome. The mortality plus liver transplant and hemodialysis composite rate was 8.2 percent, consistent with current literature. CONCLUSION: The California Poison Control System has relatively few amatoxin-containing mushroom ingestion calls that result in hospitalization but those that are reported mostly occur in Northern California. Treatment bias towards the sickest patients may explain the association of intravenous fluid use or treatment with acetylcysteine or silibinin with meeting the composite outcome. The initial presence of elevated hepatic aminotransferase activity and international normalized ratios are poor prognostic indicators and are likely reflective of late presentation, an advanced toxic phase of amatoxin poisoning, and/or delays in time to obtain poison center consultation.

Work of Breathing During Proportional Assist Ventilation as a Predictor of Extubation Failure.

BACKGROUND: Despite decades of research on predictors of extubation success, use of ventilatory support after extubation is common and 10-20% of patients require re-intubation. Proportional assist ventilation (PAV) mode automatically calculates estimated total work of breathing (total WOB). Here, we assessed the performance of total WOB to predict extubation failure in invasively ventilated subjects. METHODS: This prospective observational study was conducted in 6 adult ICUs at an academic medical center. We enrolled intubated subjects who successfully completed a spontaneous breathing trial, had a rapid shallow breathing index < 105 breaths/min/L, and were deemed ready for extubation by the primary team. Total WOB values were recorded at the end of a 30-min PAV trial. Extubation failure was defined as any respiratory support and/or re-intubation within 72 h of extubation. We compared total WOB scores between groups and performance of total WOB for predicting extubation failure with receiver operating characteristic curves. RESULTS: Of 61 subjects enrolled, 9.8% (n = 6) required re-intubation, and 50.8% (n = 31) required any respiratory support within 72 h of extubation. Median total WOB at 30 min on PAV was 0.9 J/L (interquartile range 0.7-1.3 J/L). Total WOB was significantly different between subjects who failed or were successfully extubated (median 1.1 J/L vs 0.7 J/L, P = .004). The area under the curve was 0.71 [95% CI 0.58-0.85] for predicting any requirement of respiratory support and 0.85 [95% CI 0.69-1.00] for predicting re-intubation alone within 72 h of extubation. Total WOB cutoff values maximizing sensitivity and specificity equally were 1.0 J/L for any respiratory support (positive predictive value [PPV] 70.0%, negative predictive value [NPV] 67.7%) and 1.3 J/L for re-intubation (PPV 26.3%, NPV 97.6%). CONCLUSIONS: The discriminative performance of a PAV-derived total WOB value to predict extubation failure was good, indicating total WOB may represent an adjunctive tool for assessing extubation readiness. However, these results should be interpreted as preliminary, with specific thresholds of PAV-derived total WOB requiring further investigation in a large multi-center study.

Noninvasive vs Invasive Respiratory Support for Patients with Acute Hypoxemic Respiratory Failure.

Rationale: Noninvasive respiratory support modalities are common alternatives to mechanical ventilation for patients with early acute hypoxemic respiratory failure. These modalities include noninvasive positive pressure ventilation, using either continuous or bilevel positive airway pressure, and nasal high flow using a high flow nasal cannula system. However, outcomes data historically compare noninvasive respiratory support to conventional oxygen rather than to mechanical ventilation. Objectives: The goal of this study was to compare the outcomes of in-hospital death and alive discharge in patients with acute hypoxemic respiratory failure when treated initially with noninvasive respiratory support compared to patients treated initially with invasive mechanical ventilation. Methods: We used a validated phenotyping algorithm to classify all patients with eligible International Classification of Diseases codes at a large healthcare network between January 1, 2018 and December 31, 2019 into noninvasive respiratory support and invasive mechanical ventilation cohorts. The primary outcome was time-to-in-hospital death analyzed using an inverse probability of treatment weighted Cox model adjusted for potential confounders, with estimated cumulative incidence curves. Secondary outcomes included time-to-hospital discharge alive. A secondary analysis was conducted to examine potential differences between noninvasive positive pressure ventilation and nasal high flow. Results: During the study period, 3177 patients met inclusion criteria (40% invasive mechanical ventilation, 60% noninvasive respiratory support). Initial noninvasive respiratory support was not associated with a decreased hazard of in-hospital death (HR: 0.65, 95% CI: 0.35 - 1.2), but was associated with an increased hazard of discharge alive (HR: 2.26, 95% CI: 1.92 - 2.67). In-hospital death varied between the nasal high flow (HR 3.27, 95% CI: 1.43 - 7.45) and noninvasive positive pressure ventilation (HR 0.52, 95% CI 0.25 - 1.07), but both were associated with increased likelihood of discharge alive (nasal high flow HR 2.12, 95 CI: 1.25 - 3.57; noninvasive positive pressure ventilation HR 2.29, 95% CI: 1.92 - 2.74). Conclusion: These observational data from a large healthcare network show that noninvasive respiratory support is not associated with reduced hazards of in-hospital death but is associated with hospital discharge alive. There are also potential differences between the noninvasive respiratory support modalities.

A Least Absolute Shrinkage and Selection Operator-Derived Predictive Model for Postoperative Respiratory Failure in a Heterogeneous Adult Elective Surgery Patient Population.

BACKGROUND: Postoperative respiratory failure (PRF) is associated with increased hospital charges and worse patient outcomes. Reliable prediction models can help to guide postoperative planning to optimize care, to guide resource allocation, and to foster shared decision-making with patients. RESEARCH QUESTION: Can a predictive model be developed to accurately identify patients at high risk of PRF? STUDY DESIGN AND METHODS: In this single-site proof-of-concept study, we used structured query language to extract, transform, and load electronic health record data from 23,999 consecutive adult patients admitted for elective surgery (2014-2021). Our primary outcome was PRF, defined as mechanical ventilation after surgery of > 48 h. Predictors of interest included demographics, comorbidities, and intraoperative factors. We used logistic regression to build a predictive model and the least absolute shrinkage and selection operator procedure to select variables and to estimate model coefficients. We evaluated model performance using optimism-corrected area under the receiver operating curve and area under the precision-recall curve and calculated sensitivity, specificity, positive and negative predictive values, and Brier scores. RESULTS: Two hundred twenty-five patients (0.94%) demonstrated PRF. The 18-variable predictive model included: operations on the cardiovascular, nervous, digestive, urinary, or musculoskeletal system; surgical specialty orthopedic (nonspine); Medicare or Medicaid (as the primary payer); race unknown; American Society of Anesthesiologists class ≥ III; BMI of 30 to 34.9 kg/m2; anesthesia duration (per hour); net fluid at end of the operation (per liter); median intraoperative FIO2, end title CO2, heart rate, and tidal volume; and intraoperative vasopressor medications. The optimism-corrected area under the receiver operating curve was 0.835 (95% CI,0.808-0.862) and the area under the precision-recall curve was 0.156 (95% CI, 0.105-0.203). INTERPRETATION: This single-center proof-of-concept study demonstrated that a structured query language extract, transform, and load process, based on readily available patient and intraoperative variables, can be used to develop a prediction model for PRF. This PRF prediction model is scalable for multicenter research. Clinical applications include decision support to guide postoperative level of care admission and treatment decisions.

Postoperative respiratory failure: An update on the validity of the Agency for Healthcare Research and Quality Patient Safety Indicator 11 in an era of clinical documentation improvement programs.

BACKGROUND: Administrative data can be used to identify cases of postoperative respiratory failure (PRF). We aimed to determine if recent changes to the Agency for Healthcare Research and Quality Patient Safety Indicator 11 (PSI 11) and adoption of clinical documentation improvement programs have improved the validity of PSI 11. We also analyzed reasons why PSI 11 was falsely triggered. STUDY DESIGN: Cross-sectional study of all eligible discharges using health record data from five academic medical centers between October 1, 2012 and September 30, 2015. RESULTS: Of 437 flagged records, 434 (99.3%) were accurately coded and 414 (94.7%) represented true clinical PRF. None of the false positive records involved respiratory failure present on admission. Most (78.3%) false positive records required airway protection but did not have respiratory failure. CONCLUSION: The validity of PSI 11 has improved with recent changes to the code criterion and adoption of clinical documentation improvement programs.