Neuraxial clonidine is not associated with lower post-cesarean opioid consumption or pain scores in parturients on chronic buprenorphine therapy: a retrospective cohort study

PURPOSE

Adequate post-cesarean delivery analgesia can be difficult to achieve for women diagnosed with opioid use disorder receiving buprenorphine. We sought to determine if neuraxial clonidine administration is associated with decreased opioid consumption and pain scores following cesarean delivery in women receiving chronic buprenorphine therapy.

METHODS

This was a retrospective cohort study at a tertiary care teaching hospital of women undergoing cesarean delivery with or without neuraxial clonidine administration while receiving chronic buprenorphine. The primary outcome was opioid consumption (in morphine milligram equivalents) 0-6 h following cesarean delivery. Secondary outcomes included opioid consumption 0-24 h post-cesarean, median postoperative pain scores 0-24 h, and rates of intraoperative anesthetic supplementation. Multivariable analysis evaluating the adjusted effects of neuraxial clonidine on outcomes was conducted using linear regression, proportional odds model, and logistic regression separately.

RESULTS

196 women met inclusion criteria, of which 145 (74%) received neuraxial clonidine while 51 (26%) did not. In univariate analysis, there was no significant difference in opioid consumption 0-6 h post-cesarean delivery between the clonidine (8 [IQR 0, 15]) and control (1 [IQR 0, 8]) groups (P = 0.14). After adjusting for potential confounders, there remained no significant association with neuraxial clonidine administration 0-6 h (Difference in means 2.77, 95% CI [- 0.89 to 6.44], P = 0.14) or 0-24 h (Difference in means 8.56, 95% CI [- 16.99 to 34.11], P = 0.51).

CONCLUSION

In parturients receiving chronic buprenorphine therapy at the time of cesarean delivery, neuraxial clonidine administration was not associated with decreased postoperative opioid consumption, median pain scores, or the need for intraoperative supplementation.

Determinants and practice variability of oxygen administration during surgery in the U.S., a retrospective cohort study

BACKGROUND

The best approaches to supplemental oxygen administration during surgery remain unclear, which may contribute to variation in practice. We aimed to assess determinants of oxygen administration and its variability during surgery.

METHODS

Using multivariable linear mixed-effects regression, we measured the associations between intraoperative fraction of inspired oxygen and patient, procedure, medical center, anesthesiologist, and in-room anesthesia provider factors in surgical cases of 120 minutes or longer in adult patients who received general anesthesia with tracheal intubation and were admitted to the hospital after surgery between January 2016 and January 2019 at 42 medical centers across the U.S. participating in the Multicenter Perioperative Outcomes Group data registry.

RESULTS

The sample included 367,841 cases (median [25 th, 75 th] age, 59 [47, 69] years; 51.1% women; 26.1% treated with nitrous oxide) managed by 3,836 anesthesiologists and 15,381 in-room anesthesia providers. Median (25 th, 75 th) fraction of inspired oxygen was 0.55 (0.48, 0.61), with 6.9% of cases <0.40 and 8.7% >0.90. Numerous patient and procedure factors were statistically associated with increased inspired oxygen, notably advanced ASA classification, heart disease, emergency surgery, and cardiac surgery, but most factors had little clinical significance (<1% inspired oxygen change). Overall, patient factors only explained 3.5% (95% CI, 3.5 to 3.5) of the variability in oxygen administration and procedure factors 4.4% (4.2 to 4.6). Anesthesiologist explained 7.7% (7.2 to 8.2) of the variability in oxygen administration, in-room anesthesia provider 8.1% (7.8 to 8.4), medical center 23.3% (22.4 to 24.2), and 53.0% (95% CI, 52.4 to 53.6) was unexplained.

CONCLUSIONS

Among adults undergoing surgery with anesthesia and tracheal intubation, supplemental oxygen administration was variable and appeared arbitrary. Most patient and procedure factors had statistical but minor clinical associations with oxygen administration. Medical center and anesthesia provider explained significantly more variability in oxygen administration than patient or procedure factors.

Red Blood Cell Transfusion and Pulmonary Complications: The Society of Thoracic Surgeons Adult Cardiac Surgery Database Analysis

BACKGROUND

Intraoperative packed red blood cell (PRBC) transfusion during cardiac surgery is associated with increased postoperative morbidity and mortality; however, data on the association between PRBC transfusion and postoperative pulmonary complications (PPCs) are somewhat conflicting. Using The Society of Thoracic Surgeons Adult Cardiac Surgery Database, we sought to determine whether intraoperative PRBC transfusion was associated with PPCs as well as with longer intensive care unit (ICU) stay after isolated coronary artery bypass grafting (CABG) surgery.

METHODS

A registry-based cohort study was performed on 751,893 patients with isolated CABG between January 1, 2015, to December 31, 2019. Using propensity score-weighted regression analysis, we analyzed the effect of intraoperative PRBC on the incidence of PPCs (hospital-acquired pneumonia [HAP], mechanical ventilation for >24 hours, or reintubation), ICU length of stay, and ICU readmission.

RESULTS

Transfusion of 1, 2, 3, and ≥4 units of PRBCs was associated with increased odds for HAP (odds ratios [ORs], 1.24 [95% CI, 1.21-1.26], 1.28 [95% CI, 1.26-1.32], 1.36 [95% CI, 1.33-1.39], 1.31 [95% CI, 1.28-1.34]), reintubation (ORs, 1.23 [95% CI, 1.21-1.25], 1.38 [95% CI, 1.35-1.40], 1.57 [95% CI, 1.55-1.60], 1.70 [95% CI, 1.67-1.73]), prolonged ventilation (ORs, 1.34 [95% CI, 1.33-1.36], 1.56 [95% CI, 1.53-1.58], 1.97 [95% CI, 1.94-2.00], 2.27 [95% CI, 2.24-2.30]), initial ICU length of stay (mean difference in hours, 6.79 [95% CI, 6.00-7.58], 9.55 [95% CI, 8.71-10.38], 17.26 [95% CI, 16.38-18.15], 22.14 [95% CI, 21.22-23.06]), readmission to ICU (ORs, 1.14 [95% CI, 1.12-1.64], 1.15 [95% CI, 1.12-1.17], 1.15 [95% CI, 1.13-1.18], 1.32 [95% CI, 1.29-1.35]), and additional ICU length of stay (mean difference in hours, 0.55 [95% CI, 0.18-0.92], 0.38 [95% CI, 0.00-0.77], 1.02 [95% CI, 0.61-1.43], 1.83 [95% CI, 1.40-2.26]), respectively.

CONCLUSIONS

Intraoperative PRBC transfusion was associated with increased incidence of PPCs, prolonged ICU stay, and ICU readmissions after isolated CABG surgery.

The Association between Preoperative Blood Pressures and Postoperative Adverse Events

BACKGROUND

The relationship between postoperative adverse events and blood pressures in the preoperative period remains poorly understood. This study tested the hypothesis that day-of-surgery preoperative blood pressures are associated with postoperative adverse events.

METHODS

We conducted a retrospective, observational study of adult patients having elective procedures requiring an inpatient stay between November 2017 and July 2021 at Vanderbilt University Medical Center to examine the independent associations between preoperative systolic and diastolic blood pressures (SBP, DBP) recorded immediately before anesthesia care and number of postoperative adverse events - myocardial injury, stroke, acute kidney injury (AKI), and mortality, while adjusting for potential confounders. We used multivariable ordinal logistic regression to model the relationship.

RESULTS

The analysis included 57,389 cases. The overall incidence of myocardial injury, stroke, AKI, and mortality within 30 days of surgery was 3.4% (1,967 events), 0.4% (223), 10.2% (5,871), and 2.1% (1,223), respectively. The independent associations between both SBP and DBP measurements and number of postoperative adverse events were found to be U-shaped, with greater risk both above and below SBP 143 mmHg and DBP 86 mmHg - the troughs of the curves. The associations were strongest at SBP 173 mmHg (adjusted odds ratio [aOR] 1.212 versus 143 mmHg; 95% CI, 1.021 to 1.439; p = 0.028), SBP 93 mmHg (aOR 1.339 versus 143 mmHg; 95% CI, 1.211 to 1.479; p < 0.001), DBP 106 mmHg (aOR 1.294 versus 86 mmHg; 95% CI, 1.003 to 1.17671; p = 0.048), and DBP 46 mmHg (aOR 1.399 versus 86 mmHg; 95% CI, 1.244 to 1.558; p < 0.001).

CONCLUSIONS

Preoperative blood pressures both below and above a specific threshold were independently associated with a higher number of postoperative adverse events, but the data do not support specific strategies for managing patients with low or high blood pressure on the day of surgery.

Protocol and Statistical Analysis Plan for the Mode of Ventilation During Critical Illness (MODE) Trial

BACKGROUND

For every critically ill adult receiving invasive mechanical ventilation, clinicians must select a mode of ventilation. The mode of ventilation determines whether the ventilator directly controls the tidal volume or the inspiratory pressure. Newer hybrid modes allow clinicians to set a target tidal volume; the ventilator controls and adjusts the inspiratory pressure. A strategy of low tidal volumes and low plateau pressure improves outcomes, but the optimal mode to achieve these targets is not known.

RESEARCH QUESTION

Can a cluster-randomized trial design be used to assess whether the mode of mandatory ventilation affects the number of days alive and free of invasive mechanical ventilation among critically ill adults?

STUDY DESIGN AND METHODS

The Mode of Ventilation During Critical Illness (MODE) trial is a cluster-randomized, multiple-crossover pilot trial being conducted in the medical ICU at an academic center. The MODE trial compares the use of volume control, pressure control, and adaptive pressure control. The study ICU is assigned to a single-ventilator mode (volume control vs pressure control vs adaptive pressure control) for continuous mandatory ventilation during each 1-month study block. The assigned mode switches every month in a randomly generated sequence. The primary outcome is ventilator-free days to study day 28, defined as the number of days alive and free of invasive mechanical ventilation from the final receipt of mechanical ventilation to 28 days after enrollment. Enrollment began November 1, 2022, and will end on July 31, 2023.

RESULTS

This manuscript describes the protocol and statistical analysis plan for the MODE trial of ventilator modes comparing volume control, pressure control, and adaptive pressure control.

INTERPRETATION

Prespecifying the full statistical analysis plan prior to completion of enrollment increases rigor, reproducibility, and transparency of the trial results.

CLINICAL TRIAL REGISTRATION

The trial was registered with clinicaltrials.gov on October 3, 2022, before initiation of patient enrollment on November 1, 2022 (ClinicalTrials.gov identifier: NCT05563779).

Improving Neuromuscular Monitoring Through Education-Based Interventions and Studying Its Association With Adverse Postoperative Outcomes: A Retrospective Observational Study

BACKGROUND

We assessed the association between education-based interventions, the frequency of train-of-four (TOF) monitoring, and postoperative outcomes.

METHODS

We studied adults undergoing noncardiac surgery from February 1, 2020 through October 31, 2021. Our education-based interventions consisted of 3 phases. An interrupted time-series analysis, adjusting for patient- and procedure-related characteristics and secular trends over time, was used to assess the associations between education-based interventions and the frequency of TOF monitoring, postoperative pulmonary complications (PPCs), 90-day mortality, and sugammadex dosage. For each outcome and intervention phase, we tested whether the intervention at that phase was associated with an immediate change in the outcome or its trend (weekly rate of change) over time. In a sensitivity analysis, the association between education-based interventions and postoperative outcomes was adjusted for TOF monitoring.

RESULTS

Of 19,422 cases, 11,636 (59.9%) had documented TOF monitoring. Monitoring frequency increased from 44.2% in the first week of preintervention stage to 83.4% in the final week of the postintervention phase. During the preintervention phase, the odds of TOF monitoring trended upward by 0.5% per week (odds ratio [OR], 1.005; 95% confidence interval [CI], 1.002-1.007). Phase 1 saw an immediate 54% increase (OR, 1.54; 95% CI, 1.33-1.79) in the odds, and the trend OR increased by 3% (OR, 1.03; 95% CI, 1.01-1.05) to 1.035, or 3.5% per week (joint Wald test, P < .001). Phase 2 was associated with a further immediate 29% increase (OR, 1.29; 95% CI, 1.02-1.64) but no significant association with trend (OR, 0.96; 95% CI, 0.93-1.01) of TOF monitoring (joint test, P = .04). Phase 3 and postintervention phase were not significantly associated with the frequency of TOF monitoring (joint test, P = .16 and P = .61). The study phases were not significantly associated with PPCs or sugammadex administration. The trend OR for 90-day mortality was larger by 24% (OR, 1.24; 95% CI, 1.06-1.45; joint test, P = .03) in phase 2 versus phase 1, from a weekly decrease of 8% to a weekly increase of 14%. However, this trend reversed again at the transition from phase 3 to the postintervention phase (OR, 0.82; 95% CI, 0.68-0.99; joint test, P = .05), from a 14% weekly increase to a 6.2% weekly decrease in the odds of 90-day mortality. In sensitivity analyses, adjusting for TOF monitoring, we found similar associations between study initiatives and postoperative outcomes. TOF monitoring was associated with lower odds of PPCs (OR, 0.69; 95% CI, 0.55-0.86) and 90-day mortality (OR, 0.79; 95% CI, 0.63-0.98), but not sugammadex dosing (mean difference, -0.02; 95% CI, -0.04 to 0.01).

CONCLUSIONS

Our education-based interventions were associated with both TOF utilization and 90-day mortality but were not associated with either the odds of PPCs or sugammadex dosing. TOF monitoring was associated with reduced odds of PPCs and 90-day mortality.

The Association of Nonmodifiable Patient Factors on Antipsychotic Medication use in the Intensive Care Unit

PURPOSE

We investigated the association of age, sex, race, and insurance status on antipsychotic medication use among intensive care unit (ICU) patients.

MATERIALS AND METHODS

Retrospective study of adults admitted to ICUs at a tertiary academic center. Patient characteristics, hospital course, and medication (olanzapine, quetiapine, and haloperidol) data were collected. Logistic regression models evaluated the independent association of age, sex, race, and insurance status on the use of each antipsychotic, adjusting for prespecified covariates.

RESULTS

Of 27,137 encounters identified, 6191 (22.8%) received antipsychotics. Age was significantly associated with the odds of receiving olanzapine (P < .001), quetiapine (P = .001), and haloperidol (P = .0046). Male sex and public insurance status were associated with increased odds of receiving antipsychotics olanzapine, quetiapine, and haloperidol (Male vs Female: OR 1.13, 95% CI [1.04, 1.24], P = .0005; OR 1.22, 95% CI [1.10, 1.34], P = .0001; OR 1.28, 95% CI [1.17, 1.40], P < .0001, respectively; public insurance vs private insurance: OR 1.32, 95% CI [1.20, 1.46], P < .0001; OR 1.21, 95% CI [1.09, 1.34], P = .0004; OR 1.15, 95% CI [1.04, 1.27], P = .0058, respectively). Black race was also associated with a decreased odds of receiving all antipsychotics (olanzapine (P = .0177), quetiapine (P = .004), haloperidol (P = .0041)).

CONCLUSIONS

Age, sex, race, and insurance status were associated with the use of all antipsychotic medications investigated, highlighting the importance of investigating the potential impact of these prescribing decisions on patient outcomes across diverse populations. Recognizing how nonmodifiable patient factors have the potential to influence prescribing practices may be considered an important factor toward optimizing medication regimens.

Randomized controlled trial of urinE chemiStry guided aCute heArt faiLure treATmEnt (ESCALATE): Rationale and design

Diuresis to achieve decongestion is a central aim of therapy in patients hospitalized for acute decompensated heart failure (ADHF). While multiple clinical trials have investigated initial diuretic strategies for a designated period of time, there is a paucity of evidence to guide diuretic titration strategies continued until decongestion is achieved. The use of urine chemistries (urine sodium and creatinine) in a natriuretic response prediction equation accurately estimates natriuresis in response to diuretic dosing, but a randomized clinical trial is needed to compare a urine chemistry-guided diuresis strategy with a strategy of usual care. The urinE chemiStry guided aCute heArt faiLure treATmEnt (ESCALATE) trial is designed to test the hypothesis that protocolized diuretic therapy guided by spot urine chemistry through completion of intravenous diuresis will be superior to usual care and improve outcomes over the 14 days following randomization. ESCALATE will randomize and obtain complete data on 450 patients with acute heart failure to a diuretic strategy guided by urine chemistry or a usual care strategy. Key inclusion criteria include an objective measure of hypervolemia with at least 10 pounds of estimated excess volume, and key exclusion criteria include significant valvular stenosis, hypotension, and a chronic need for dialysis. Our primary outcome is days of benefit over the 14 days after randomization. Days of benefit combines patient symptoms captured by global clinical status with clinical state quantifying the need for hospitalization and intravenous diuresis. CLINICAL TRIAL REGISTRATION: NCT04481919.

Cefepime vs Piperacillin-Tazobactam in Adults Hospitalized With Acute Infection: The ACORN Randomized Clinical Trial

Importance

Cefepime and piperacillin-tazobactam are commonly administered to hospitalized adults for empirical treatment of infection. Although piperacillin-tazobactam has been hypothesized to cause acute kidney injury and cefepime has been hypothesized to cause neurological dysfunction, their comparative safety has not been evaluated in a randomized clinical trial.

Objective

To determine whether the choice between cefepime and piperacillin-tazobactam affects the risks of acute kidney injury or neurological dysfunction.

Design, Setting, and Participants

The Antibiotic Choice on Renal Outcomes (ACORN) randomized clinical trial compared cefepime vs piperacillin-tazobactam in adults for whom a clinician initiated an order for antipseudomonal antibiotics within 12 hours of presentation to the hospital in the emergency department or medical intensive care unit at an academic medical center in the US between November 10, 2021, and October 7, 2022. The final date of follow-up was November 4, 2022.

Interventions

Patients were randomized in a 1:1 ratio to cefepime or piperacillin-tazobactam.

Main Outcomes and Measures

The primary outcome was the highest stage of acute kidney injury or death by day 14, measured on a 5-level ordinal scale ranging from no acute kidney injury to death. The 2 secondary outcomes were the incidence of major adverse kidney events at day 14 and the number of days alive and free of delirium and coma within 14 days.

Results

There were 2511 patients included in the primary analysis (median age, 58 years [IQR, 43-69 years]; 42.7% were female; 16.3% were Non-Hispanic Black; 5.4% were Hispanic; 94.7% were enrolled in the emergency department; and 77.2% were receiving vancomycin at enrollment). The highest stage of acute kidney injury or death was not significantly different between the cefepime group and the piperacillin-tazobactam group; there were 85 patients (n = 1214; 7.0%) in the cefepime group with stage 3 acute kidney injury and 92 (7.6%) who died vs 97 patients (n = 1297; 7.5%) in the piperacillin-tazobactam group with stage 3 acute kidney injury and 78 (6.0%) who died (odds ratio, 0.95 [95% CI, 0.80 to 1.13], P = .56). The incidence of major adverse kidney events at day 14 did not differ between groups (124 patients [10.2%] in the cefepime group vs 114 patients [8.8%] in the piperacillin-tazobactam group; absolute difference, 1.4% [95% CI, -1.0% to 3.8%]). Patients in the cefepime group experienced fewer days alive and free of delirium and coma within 14 days (mean [SD], 11.9 [4.6] days vs 12.2 [4.3] days in the piperacillin-tazobactam group; odds ratio, 0.79 [95% CI, 0.65 to 0.95]).

Conclusions and Relevance

Among hospitalized adults in this randomized clinical trial, treatment with piperacillin-tazobactam did not increase the incidence of acute kidney injury or death. Treatment with cefepime resulted in more neurological dysfunction.

Trial Registration

ClinicalTrials.gov Identifier: NCT05094154.

Preemptive Pharmacogenetic-Guided Metoprolol Management for Postoperative Atrial Fibrillation in Cardiac Surgery: The Preemptive Pharmacogenetic-Guided Metoprolol Management for Atrial Fibrillation in Cardiac Surgery Pilot Trial

OBJECTIVES

To test the hypothesis that implementation of a cytochrome P-450 2D6 (CYP2D6) genotype-guided perioperative metoprolol administration will reduce the risk of postoperative atrial fibrillation (AF), the authors conducted the Preemptive Pharmacogenetic-Guided Metoprolol Management for Atrial Fibrillation in Cardiac Surgery pilot study.

DESIGN

Clinical pilot trial.

SETTING

Single academic center.

PARTICIPANTS

Seventy-three cardiac surgery patients.

MEASUREMENTS AND MAIN RESULTS

Patients were classified as normal, intermediate, poor, or ultrarapid metabolizers after testing for their CYP2D6 genotype. A clinical decision support tool in the electronic health record advised providers on CYP2D6 genotype-guided metoprolol dosing. Using historical data, the Bayesian method was used to compare the incidence of postoperative AF in patients with altered metabolizer status to the reference incidence. A logistic regression analysis was performed to study the association between the metabolizer status and postoperative AF while controlling for the Multicenter Study of Perioperative Ischemia AF Risk Index. Of the 73 patients, 30% (n = 22) developed postoperative AF; 89% (n = 65) were normal metabolizers; 11% (n = 8) were poor/intermediate metabolizers; and there were no ultrarapid metabolizer patients identified. The estimated rate of postoperative AF in patients with altered metabolizer status was 30% (95% CI 8%-60%), compared with the historical reference incidence (27%). In the risk-adjusted analysis, there was insufficient evidence to conclude that modifying metoprolol dosing based on poor/intermediate metabolizer status was associated significantly with the odds of postoperative AF (odds ratio 0.82, 95% CI 0.15-4.55, p = 0.82).

CONCLUSIONS

A CYP2D6 genotype-guided metoprolol management was not associated with a reduction of postoperative AF after cardiac surgery.

Association of Intraoperative Red Blood Cell Transfusions With Venous Thromboembolism and Adverse Outcomes After Cardiac Surgery

OBJECTIVE

We determined whether intraoperative packed red blood cell (PRBC) transfusion was associated with a higher incidence of hospital-acquired venous thromboembolic (HA-VTE) complications and adverse outcomes after isolated coronary artery bypass grafting (CABG) surgery.

BACKGROUND

Intraoperative PRBC has been associated with increased risk for postoperative deep venous thrombosis after cardiac surgery, but validation of these findings in a large, multi-institutional, national cohort of cardiac surgery patients has been lacking.

METHODS

A registry-based cohort study of 751,893 patients with isolated CABG between January 1, 2015, to December 31, 2019. Using propensity score-weighted regression analysis, we analyzed the effect of intraoperative PRBC on the incidence of HA-VTE and adverse outcomes.

RESULTS

Administration of 1, 2, 3, and ≥4 units of PRBC transfusion was associated with increased odds for HA-VTE [odds ratios (ORs): 1.27 (1.22-1.32), 1.21 (1.16-1.26), 1.93 (1.85-2.00), 1.82 (1.75-1.89)], deep venous thrombosis [ORs: 1.39 (1.33-1.46), 1.38 (1.32-1.44), 2.18 (2.09-2.28), 1.82 (1.74-1.91], operative mortality [ORs: 1.11 (1.08-1.14), 1.16 (1.13-1.19), 1.29 (1.26-1.32), 1.47 (1.43-1.50)], readmission within 30 days [ORs: 1.05 (1.04-1.06), 1.16 (1.13-1.19), 1.29 (1.26-1.32), 1.47 (1.43-1.50)], and a prolonged postoperative length of stay [mean difference in days, 0.23 (0.19-0.27), 0.34 (0.30-0.39), 0.69 (0.64-0.74), 0.77 (0.72-0.820]. The odds of pulmonary venous thromboembolism were lower for patients transfused with 1 or 2 units [ORs: 0.98 (0.91-1.06), 0.75 (0.68-0.81)] of PRBC but remained significantly elevated for those receiving 3 and ≥4 units [ORs: 1.19 (1.09-1.29), 1.35 (1.25-1.48)].

CONCLUSIONS

Intraoperative PRBC transfusion was associated with HA-VTE and adverse outcomes after isolated CABG surgery.

PeRiOperative Glucose PRAgMatic (PROGRAM) trial protocol and statistical analysis plan for comparing automated intraoperative reminders to standardise insulin administration in surgical patients at high risk of hyperglycaemia

INTRODUCTION

Studies finding perioperative hyperglycaemia is associated with adverse patient outcomes in surgical procedures spurred the development of blood glucose guidelines at many institutions. In this trial, we will assess the implementation of a clinical decision support tool that is integrated into the intraoperative portion of our electronic health record and provides real-time best practice recommendations for intraoperative insulin dosing in surgical patients at high risk for hyperglycaemia.

METHODS AND DESIGN

We will assess this intervention using a sequential and repeated cross-over design at the institutional level with periods of time for wash-out, control and study intervention. The unit of analysis will be the surgical case. The primary outcome will be the frequency of hyperglycaemia (>180 mg/dL (10 mmol/L)) at first postoperative anaesthesia care unit measurement. There are several prespecified secondary analyses focused on perioperative glycaemic control.

DISCUSSION

This protocol and statistical analysis plan describes the methodology, primary and secondary analyses. The PeRiOperative Glucose PRAgMatic (PROGRAM) trial was approved by the Vanderbilt University Institutional Review Board (IRB), Vanderbilt University Medical Center, Nashville, Tennessee, USA (IRB, 220991). The study results will be disseminated via publication in a peer-reviewed journal and presented at national scientific conferences. The results of PROGRAM trial will inform best practice for perioperative standardised insulin administration in surgical patients at high risk of hyperglycaemia.

TRIAL REGISTRATION NUMBER

NCT05426096.

Protocol and statistical analysis plan for the Mode of Ventilation During Critical IllnEss (MODE) trial

Introduction

For every critically ill adult receiving invasive mechanical ventilation, clinicians must select a mode of ventilation. The mode of ventilation determines whether the ventilator directly controls the tidal volume or the inspiratory pressure. Newer hybrid modes allow clinicians to set a target tidal volume, for which the ventilator controls and adjusts the inspiratory pressure. A strategy of low tidal volumes and low plateau pressure improves outcomes, but the optimal mode to achieve these targets is not known.

Methods and analysis

The Mode of Ventilation During Critical Illness (MODE) trial is a cluster-randomized, multiple-crossover pilot trial being conducted in the medical intensive care unit (ICU) at an academic center. The MODE trial compares the use of volume control, pressure control, and adaptive pressure control. The study ICU is assigned to a single ventilator mode (volume control versus pressure control versus adaptive pressure control) for continuous mandatory ventilation during each 1-month study block. The assigned mode switches every month in a randomly generated sequence. The primary outcome is ventilator-free days (VFDs) to study day 28, defined as the number of days alive and free of invasive mechanical ventilation from the final receipt of mechanical ventilation to 28 days after enrollment. Enrollment began November 1, 2022 and will end on July 31, 2023.

Ethics and dissemination

The trial was approved by the Vanderbilt University Medical Center institutional review board (IRB# 220446). Results of this study will be submitted to a peer-reviewed journal and presented at scientific conferences.

Trial registration number

The trial was registered with clinicaltrials.gov on October 3, 2022, prior to initiation of patient enrollment on November 1, 2022 (ClinicalTrials.gov identifier: NCT05563779).

Peripheral Intravenous Waveform Analysis Responsiveness to Subclinical Hemorrhage in a Rat Model

BACKGROUND

Early detection and quantification of perioperative hemorrhage remains challenging. Peripheral intravenous waveform analysis (PIVA) is a novel method that uses a standard intravenous catheter to detect interval hemorrhage. We hypothesize that subclinical blood loss of 2% of the estimated blood volume (EBV) in a rat model of hemorrhage is associated with significant changes in PIVA. Secondarily, we will compare PIVA association with volume loss to other static, invasive, and dynamic markers.

METHODS

Eleven male Sprague Dawley rats were anesthetized and mechanically ventilated. A total of 20% of the EBV was removed over ten 5 minute-intervals. The peripheral intravenous pressure waveform was continuously transduced via a 22-G angiocatheter in the saphenous vein and analyzed using MATLAB. Mean arterial pressure (MAP) and central venous pressure (CVP) were continuously monitored. Cardiac output (CO), right ventricular diameter (RVd), and left ventricular end-diastolic area (LVEDA) were evaluated via transthoracic echocardiogram using the short axis left ventricular view. Dynamic markers such as pulse pressure variation (PPV) were calculated from the arterial waveform. The primary outcome was change in the first fundamental frequency (F1) of the venous waveform, which was assessed using analysis of variance (ANOVA). Mean F1 at each blood loss interval was compared to the mean at the subsequent interval. Additionally, the strength of the association between blood loss and F1 and each other marker was quantified using the marginal R2 in a linear mixed-effects model.

RESULTS

PIVA derived mean F1 decreased significantly after hemorrhage of only 2% of the EBV, from 0.17 to 0.11 mm Hg, P = .001, 95% confidence interval (CI) of difference in means 0.02 to 0.10, and decreased significantly from the prior hemorrhage interval at 4%, 6%, 8%, 10%, and 12%. Log F1 demonstrated a marginal R2 value of 0.57 (95% CI 0.40-0.73), followed by PPV 0.41 (0.28-0.56) and CO 0.39 (0.26-0.58). MAP, LVEDA, and systolic pressure variation displayed R2 values of 0.31, and the remaining predictors had R2 values ≤0.2. The difference in log F1 R2 was not significant when compared to PPV 0.16 (95% CI -0.07 to 0.38), CO 0.18 (-0.06 to 0.04), or MAP 0.25 (-0.01 to 0.49) but was significant for the remaining markers.

CONCLUSIONS

The mean F1 amplitude of PIVA was significantly associated with subclinical blood loss and most strongly associated with blood volume among the markers considered. This study demonstrates feasibility of a minimally invasive, low-cost method for monitoring perioperative blood loss.

Renin-Angiotensin System Modulation With Synthetic Angiotensin (1-7) and Angiotensin II Type 1 Receptor-Biased Ligand in Adults With COVID-19: Two Randomized Clinical Trials

Importance

Preclinical models suggest dysregulation of the renin-angiotensin system (RAS) caused by SARS-CoV-2 infection may increase the relative activity of angiotensin II compared with angiotensin (1-7) and may be an important contributor to COVID-19 pathophysiology.

Objective

To evaluate the efficacy and safety of RAS modulation using 2 investigational RAS agents, TXA-127 (synthetic angiotensin [1-7]) and TRV-027 (an angiotensin II type 1 receptor-biased ligand), that are hypothesized to potentiate the action of angiotensin (1-7) and mitigate the action of the angiotensin II.

Design, Setting, and Participants

Two randomized clinical trials including adults hospitalized with acute COVID-19 and new-onset hypoxemia were conducted at 35 sites in the US between July 22, 2021, and April 20, 2022; last follow-up visit: July 26, 2022.

Interventions

A 0.5-mg/kg intravenous infusion of TXA-127 once daily for 5 days or placebo. A 12-mg/h continuous intravenous infusion of TRV-027 for 5 days or placebo.

Main Outcomes and Measures

The primary outcome was oxygen-free days, an ordinal outcome that classifies a patient's status at day 28 based on mortality and duration of supplemental oxygen use; an adjusted odds ratio (OR) greater than 1.0 indicated superiority of the RAS agent vs placebo. A key secondary outcome was 28-day all-cause mortality. Safety outcomes included allergic reaction, new kidney replacement therapy, and hypotension.

Results

Both trials met prespecified early stopping criteria for a low probability of efficacy. Of 343 patients in the TXA-127 trial (226 [65.9%] aged 31-64 years, 200 [58.3%] men, 225 [65.6%] White, and 274 [79.9%] not Hispanic), 170 received TXA-127 and 173 received placebo. Of 290 patients in the TRV-027 trial (199 [68.6%] aged 31-64 years, 168 [57.9%] men, 195 [67.2%] White, and 225 [77.6%] not Hispanic), 145 received TRV-027 and 145 received placebo. Compared with placebo, both TXA-127 (unadjusted mean difference, -2.3 [95% CrI, -4.8 to 0.2]; adjusted OR, 0.88 [95% CrI, 0.59 to 1.30]) and TRV-027 (unadjusted mean difference, -2.4 [95% CrI, -5.1 to 0.3]; adjusted OR, 0.74 [95% CrI, 0.48 to 1.13]) resulted in no difference in oxygen-free days. In the TXA-127 trial, 28-day all-cause mortality occurred in 22 of 163 patients (13.5%) in the TXA-127 group vs 22 of 166 patients (13.3%) in the placebo group (adjusted OR, 0.83 [95% CrI, 0.41 to 1.66]). In the TRV-027 trial, 28-day all-cause mortality occurred in 29 of 141 patients (20.6%) in the TRV-027 group vs 18 of 140 patients (12.9%) in the placebo group (adjusted OR, 1.52 [95% CrI, 0.75 to 3.08]). The frequency of the safety outcomes was similar with either TXA-127 or TRV-027 vs placebo.

Conclusions and Relevance

In adults with severe COVID-19, RAS modulation (TXA-127 or TRV-027) did not improve oxygen-free days vs placebo. These results do not support the hypotheses that pharmacological interventions that selectively block the angiotensin II type 1 receptor or increase angiotensin (1-7) improve outcomes for patients with severe COVID-19.

Trial Registration

ClinicalTrials.gov Identifier: NCT04924660.

Understanding Patient and Clinician Reported Nonroutine Events in Ambulatory Surgery

OBJECTIVE

Nonroutine events (NREs, i.e., deviations from optimal care) can identify care process deficiencies and safety risks. Nonroutine events reported by clinicians have been shown to identify systems failures, but this methodology fails to capture the patient perspective. The objective of this prospective observational study is to understand the incidence and nature of patient- and clinician-reported NREs in ambulatory surgery.

METHODS

We interviewed patients about NREs that occurred during their perioperative care using a structured interview tool before discharge and in a 7-day follow-up call. Concurrently, we interviewed the clinicians caring for these patients immediately postoperatively to collect NREs. We trained 2 experienced clinicians and 2 patients to assess and code each reported NRE for type, theme, severity, and likelihood of reoccurrence (i.e., likelihood that the same event would occur for another patient).

RESULTS

One hundred one of 145 ambulatory surgery cases (70%) contained at least one NRE. Overall, 214 NREs were reported-88 by patients and 126 by clinicians. Cases containing clinician-reported NREs were associated with increased patient body mass index ( P = 0.023) and lower postcase patient ratings of being treated with respect ( P = 0.032). Cases containing patient-reported NREs were associated with longer case duration ( P = 0.040), higher postcase clinician frustration ratings ( P < 0.001), higher ratings of patient stress ( P = 0.019), and lower patient ratings of their quality of life ( P = 0.010), of the quality of clinician teamwork ( P = 0.010), being treated with respect ( P = 0.003), and being listened to carefully ( P = 0.012). Trained patient raters evaluated NRE severity significantly higher than did clinician raters ( P < 0.001), while clinicians rated recurrence likelihood significantly higher than patients for both clinician ( P = 0.032) and patient-reported NREs ( P = 0.001).

CONCLUSIONS

Both patients and clinicians readily report events during clinical care that they believe deviate from optimal care expectations. These 2 primary stakeholders in safe, high-quality surgical care have different experiences and perspectives regarding NREs. The combination of patient- and clinician-reported NREs seems to be a promising patient-centered method of identifying healthcare system deficiencies and opportunities for improvement.

High Isoniazid Exposures When Administered with Rifapentine Once Weekly for Latent Tuberculosis in Individuals with Human Immunodeficiency Virus

Isoniazid pharmacokinetics are not yet well-described during once weekly, high-dose administrations with rifapentine (3HP) for latent tuberculosis infection (LTBI). Fewer data describe 3HP with dolutegravir-based antiretroviral therapy for the treatment of human immunodeficiency virus (HIV). The only prior report of 3HP with dolutegravir reported elevated isoniazid exposures. We measured the plasma isoniazid levels in 30 adults receiving 3HP and dolutegravir for the treatment of LTBI and HIV. The patients were genotyped to determine NAT2 acetylator status, and a population PK model was estimated by nonlinear mixed-effects modeling. The results were compared to previously reported data describing 3HP with dolutegravir, 3HP alone, and isoniazid with neither dolutegravir nor rifapentine. The isoniazid concentrations were adequately described by a one compartment model with a transit compartment absorption process. The isoniazid clearance for slow (8.33 L/h) and intermediate (12 L/h) acetylators were similar to previously reported values. Rapid acetylators (N = 4) had clearance similar to those of intermediate acetylators and much slower than typically reported, but the small sample size was limiting. The absorption rate was lower than usual, likely due to the coadministration with food, and it was faster among individuals with a low body weight. Low-body weight participants were also observed to have greater oral bioavailability. The isoniazid exposures were consistent with, or greater than, the previously reported "elevated" concentrations among individuals receiving 3HP and dolutegravir. The concentrations were substantially greater than those presented in previous reports among individuals receiving 3HP or isoniazid without rifapentine or dolutegravir. We discuss the implications of these findings and the possibility of a drug-drug interaction that is mediated by cellular transport. (This study has been registered at ClinicalTrials.gov under identifier NCT03435146 and has South African National Clinical Trial Registration no. DOH-27-1217-5770.).

Automated Emails to Improve Evening Staffing for Anesthesiologists

Scheduling flexibility and predictability to the end of a clinical workday are strategies aimed at addressing physician burnout. A voluntary relief shift was created to increase the pool of anesthesiologists providing end of the day relief. We hypothesized that an automated email reminder would improve the number of evening relief shifts filled and increase the number of anesthesiologists participating in the program. An automated email reminder was implemented, which selectively emailed anesthesiologists without a clinical assignment one day in advance when the voluntary relief shifts were not filled, and anticipated case volume past 4:00 PM was expected to exceed the capacity of the on-call team. After implementation of the automated email reminder, the median number of providers who worked the relief shift on a typical day was 2.6, compared to 1.75 prior to the intervention. After the initial increase in the number of volunteers post-intervention, the trend in the weekly average number of volunteers tended to decrease but remained higher than before the intervention. A total of 22 unique anesthesiologists chose to participate in this program after the intervention. An automated email reminder increased the number of anesthesiologists volunteering for a relief shift. Leveraging automation to match staffing needs with case volume allows for recruitment of additional personnel on the days when volunteers are most needed. Increasing the pool of anesthesiologists available to provide relief is one strategy to improve end of the day predictability and work-life balance.

Oxygen administration during surgery and postoperative organ injury: observational cohort study

OBJECTIVE

To examine whether supraphysiological oxygen administration during surgery is associated with lower or higher postoperative kidney, heart, and lung injury.

DESIGN

Observational cohort study.

SETTING

42 medical centers across the United States participating in the Multicenter Perioperative Outcomes Group data registry.

PARTICIPANTS

Adult patients undergoing surgical procedures ≥120 minutes' duration with general anesthesia and endotracheal intubation who were admitted to hospital after surgery between January 2016 and November 2018.

INTERVENTION

Supraphysiological oxygen administration, defined as the area under the curve of the fraction of inspired oxygen above air (21%) during minutes when the hemoglobin oxygen saturation was greater than 92%.

MAIN OUTCOMES

Primary endpoints were acute kidney injury defined using Kidney Disease Improving Global Outcomes criteria, myocardial injury defined as serum troponin >0.04 ng/mL within 72 hours of surgery, and lung injury defined using international classification of diseases hospital discharge diagnosis codes.

RESULTS

The cohort comprised 350 647 patients with median age 59 years (interquartile range 46-69 years), 180 546 women (51.5%), and median duration of surgery 205 minutes (interquartile range 158-279 minutes). Acute kidney injury was diagnosed in 19 207 of 297 554 patients (6.5%), myocardial injury in 8972 of 320 527 (2.8%), and lung injury in 13 789 of 312 161 (4.4%). The median fraction of inspired oxygen was 54.0% (interquartile range 47.5%-60.0%), and the area under the curve of supraphysiological inspired oxygen was 7951% min (5870-11 107% min), equivalent to an 80% fraction of inspired oxygen throughout a 135 minute procedure, for example. After accounting for baseline covariates and other potential confounding variables, increased oxygen exposure was associated with a higher risk of acute kidney injury, myocardial injury, and lung injury. Patients at the 75th centile for the area under the curve of the fraction of inspired oxygen had 26% greater odds of acute kidney injury (95% confidence interval 22% to 30%), 12% greater odds of myocardial injury (7% to 17%), and 14% greater odds of lung injury (12% to 16%) compared with patients at the 25th centile. Sensitivity analyses evaluating alternative definitions of the exposure, restricting the cohort, and conducting an instrumental variable analysis confirmed these observations.

CONCLUSIONS

Increased supraphysiological oxygen administration during surgery was associated with a higher incidence of kidney, myocardial, and lung injury. Residual confounding of these associations cannot be excluded.

TRIAL REGISTRATION

Open Science Framework osf.io/cfd2m.

Oxygen-Free Days as an Outcome Measure in Clinical Trials of Therapies for COVID-19 and Other Causes of New-Onset Hypoxemia

Mortality historically has been the primary outcome of choice for acute and critical care clinical trials. However, undue reliance on mortality can limit the scope of trials that can be performed. Large sample sizes are usually needed for trials powered for a mortality outcome, and focusing solely on mortality fails to recognize the importance that reducing morbidity can have on patients' lives. The COVID-19 pandemic has highlighted the need for rapid, efficient trials to rigorously evaluate new therapies for hospitalized patients with acute lung injury. Oxygen-free days (OFDs) is a novel outcome for clinical trials that is a composite of mortality and duration of new supplemental oxygen use. It is designed to characterize recovery from acute lung injury in populations with a high prevalence of new hypoxemia and supplemental oxygen use. In these populations, OFDs captures two patient-centered consequences of acute lung injury: mortality and hypoxemic lung dysfunction. Power to detect differences in OFDs typically is greater than that for other clinical trial outcomes, such as mortality and ventilator-free days. OFDs is the primary outcome for the Fourth Accelerating COVID-19 Therapeutic Interventions and Vaccines (ACTIV-4) Host Tissue platform, which evaluates novel therapies targeting the host response to COVID-19 among adults hospitalized with COVID-19 and new hypoxemia. This article outlines the rationale for use of OFDs as an outcome for clinical trials, proposes a standardized method for defining and analyzing OFDs, and provides a framework for sample size calculations using the OFD outcome.

SOLUBLE GUANYLYL CYCLASE ACTIVATION RESCUES HYPEROXIA-INDUCED DYSFUNCTION OF VASCULAR RELAXATION

ABSTRACT

Introduction: Perioperative alterations in perfusion lead to ischemia and reperfusion injury, and supplemental oxygen is administered during surgery to limit hypoxic injury but can lead to hyperoxia. We hypothesized that hyperoxia impairs endothelium-dependent and endothelium-independent vasodilation but not the vasodilatory response to heme-independent soluble guanylyl cyclase activation. Methods: We measured the effect of oxygen on vascular reactivity in mouse aortas. Mice were ventilated with 21% (normoxia), 60% (moderate hyperoxia), or 100% (severe hyperoxia) oxygen during 30 minutes of renal ischemia and 30 minutes of reperfusion. After sacrifice, the thoracic aorta was isolated, and segments mounted on a wire myograph. We measured endothelium-dependent and endothelium-independent vasodilation with escalating concentrations of acetylcholine (ACh) and sodium nitroprusside (SNP), respectively, and we measured the response to heme-independent soluble guanylyl cyclase activation with cinaciguat. Vasodilator responses to each agonist were quantified as the maximal theoretical response ( Emax ) and the effective concentration to elicit 50% relaxation (EC 50 ) using a sigmoid model and nonlinear mixed-effects regression. Aortic superoxide was measured with dihydroethidium probe and high-performance liquid chromatography quantification of the specific superoxide product 2-hydroxyethidium. Results: Hyperoxia impaired endothelium-dependent (ACh) and endothelium-independent (SNP) vasodilation compared with normoxia and had no effect on cinaciguat-induced vasodilation. The median ACh Emax was 76.4% (95% confidence interval = 69.6 to 83.3) in the normoxia group, 53.5% (46.7 to 60.3) in the moderate hyperoxia group, and 53.1% (46.3 to 60.0) in the severe hyperoxia group ( P < 0.001, effect across groups), while the ACh EC 50 was not different among groups. The SNP Emax was 133.1% (122.9 to 143.3) in normoxia, 128.3% (118.1 to 138.6) in moderate hyperoxia, and 114.8% (104.6 to 125.0) in severe hyperoxia ( P < 0.001, effect across groups), and the SNP EC 50 was 0.38 log M greater in moderate hyperoxia than in normoxia (95% confidence interval = 0.18 to 0.58, P < 0.001). Cinaciguat Emax and EC 50 were not different among oxygen treatment groups (median range Emax = 78.0% to 79.4% and EC 50 = -18.0 to -18.2 log M across oxygen groups). Aorta 2-hydroxyethidium was 1419 pmol/mg of protein (25th-75th percentile = 1178-1513) in normoxia, 1993 (1831-2473) in moderate hyperoxia, and 2078 (1936-2922) in severe hyperoxia ( P = 0.008, effect across groups). Conclusions: Hyperoxia, compared with normoxia, impaired endothelium-dependent and endothelium-independent vasodilation but not the response to heme-independent soluble guanylyl cyclase activation, and hyperoxia increased vascular superoxide production. Results from this study could have important implications for patients receiving high concentrations of oxygen and at risk for ischemia reperfusion-mediated organ injury.

Developing a risk stratification tool for predicting opioid-related respiratory depression after non-cardiac surgery: a retrospective study

OBJECTIVES

Accurately assessing the probability of significant respiratory depression following opioid administration can potentially enhance perioperative risk assessment and pain management. We developed and validated a risk prediction tool to estimate the probability of significant respiratory depression (indexed by naloxone administration) in patients undergoing noncardiac surgery.

DESIGN

Retrospective cohort study.

SETTING

Single academic centre.

PARTICIPANTS

We studied n=63 084 patients (mean age 47.1±18.2 years; 50% men) who underwent emergency or elective non-cardiac surgery between 1 January 2007 and 30 October 2017.

INTERVENTIONS

A derivation subsample reflecting two-thirds of available patients (n=42 082) was randomly selected for model development, and associations were identified between predictor variables and naloxone administration occurring within 5 days following surgery. The resulting probability model for predicting naloxone administration was then cross-validated in a separate validation cohort reflecting the remaining one-third of patients (n=21 002).

RESULTS

The rate of naloxone administration was identical in the derivation (n=2720 (6.5%)) and validation (n=1360 (6.5%)) cohorts. The risk prediction model identified female sex (OR: 3.01; 95% CI: 2.73 to 3.32), high-risk surgical procedures (OR: 4.16; 95% CI: 3.78 to 4.58), history of drug abuse (OR: 1.81; 95% CI: 1.52 to 2.16) and any opioids being administered on a scheduled rather than as-needed basis (OR: 8.31; 95% CI: 7.26 to 9.51) as risk factors for naloxone administration. Advanced age (OR: 0.971; 95% CI: 0.968 to 0.973), opioids administered via patient-controlled analgesia pump (OR: 0.55; 95% CI: 0.49 to 0.62) and any scheduled non-opioids (OR: 0.63; 95% CI: 0.58 to 0.69) were associated with decreased risk of naloxone administration. An overall risk prediction model incorporating the common clinically available variables above displayed excellent discriminative ability in both the derivation and validation cohorts (c-index=0.820 and 0.814, respectively).

CONCLUSION

Our cross-validated clinical predictive model accurately estimates the risk of serious opioid-related respiratory depression requiring naloxone administration in postoperative patients.

Securely sharing DSMB reports to speed decision making from multiple, concurrent, independent studies of similar treatments in COVID-19

Introduction

As clinical trials were rapidly initiated in response to the COVID-19 pandemic, Data and Safety Monitoring Boards (DSMBs) faced unique challenges overseeing trials of therapies never tested in a disease not yet characterized. Traditionally, individual DSMBs do not interact or have the benefit of seeing data from other accruing trials for an aggregated analysis to meaningfully interpret safety signals of similar therapeutics. In response, we developed a compliant DSMB Coordination (DSMBc) framework to allow the DSMB from one study investigating the use of SARS-CoV-2 convalescent plasma to treat COVID-19 to review data from similar ongoing studies for the purpose of safety monitoring.

Methods

The DSMBc process included engagement of DSMB chairs and board members, execution of contractual agreements, secure data acquisition, generation of harmonized reports utilizing statistical graphics, and secure report sharing with DSMB members. Detailed process maps, a secure portal for managing DSMB reports, and templates for data sharing and confidentiality agreements were developed.

Results

Four trials participated. Data from one trial were successfully harmonized with that of an ongoing trial. Harmonized reports allowing for visualization and drill down into the data were presented to the ongoing trial's DSMB. While DSMB deliberations are confidential, the Chair confirmed successful review of the harmonized report.

Conclusion

It is feasible to coordinate DSMB reviews of multiple independent studies of a similar therapeutic in similar patient cohorts. The materials presented mitigate challenges to DSMBc and will help expand these initiatives so DSMBs may make more informed decisions with all available information.

Defining the Epidemiology of Safety Risks in Neonatal Intensive Care Unit Patients Requiring Surgery

OBJECTIVE

The aim of the study was to determine the incidence, type, severity, preventability, and contributing factors of nonroutine events (NREs)-events perceived by care providers or skilled observers as a deviations from optimal care based on the clinical situation-in the perioperative (i.e., preoperative, operative, and postoperative) care of surgical neonates in the neonatal intensive care unit and operating room.

METHODS

A prospective observational study of noncardiac surgical neonates, who received preoperative and postoperative neonatal intensive care unit care, was conducted at an urban academic children's hospital between November 1, 2016, and March 31, 2018. One hundred twenty-nine surgical cases in 109 neonates were observed. The incidence and description of NREs were collected via structured researcher-administered survey tool of involved clinicians. Primary measurements included clinicians' ratings of NRE severity and contributory factors and trained research assistants' ratings of preventability.

RESULTS

One or more NREs were reported in 101 (78%) of 129 observed cases for 247 total NREs. Clinicians reported 2 (2) (median, interquartile range) NREs per NRE case with a maximum severity of 3 (1) (possible range = 1-5). Trained research assistants rated 47% of NREs as preventable and 11% as severe and preventable. The relative risks for National Surgical Quality Improvement Program - pediatric major morbidity and 30-day mortality were 1.17 (95% confidence interval = 0.92-1.48) and 1.04 (95% confidence interval = 1.00-1.08) in NRE cases versus non-NRE cases.

CONCLUSIONS

The incidence of NREs in neonatal perioperative care at an academic children's hospital was high and of variable severity with a myriad of contributory factors.

Post-cesarean gabapentin is not associated with lower opioid consumption or pain scores in women on chronic buprenorphine therapy: A 10-year retrospective cohort study

STUDY OBJECTIVE

To determine if postoperative gabapentin administration is associated with decreased opioid consumption or pain scores following cesarean delivery in women on chronic buprenorphine.

DESIGN

Retrospective cohort study.

SETTING

Postoperative recovery area and postpartum inpatient unit.

PATIENTS

214 women undergoing cesarean delivery while on chronic buprenorphine at a single institution between 2007 and 2017.

INTERVENTIONS

Gabapentin treatment for post-cesarean analgesia.

MEASUREMENTS

The primary outcome was opioid consumption in morphine milligram equivalents, comparing patients who received ≥1 dose of gabapentin within 24 h of cesarean delivery to those who did not. Secondary outcomes included opioid consumption 24-48 and 48-72 h post-cesarean and postoperative numerical rating scale pain scores.

MAIN RESULTS

Of 214 included patients, 64 (30%) received gabapentin while 150 (70%) did not. Gabapentin patients were more likely than controls to have received neuraxial fentanyl (30% vs. 14%, p = 0.01) and transversus abdominis plane block (6% vs. 1%, p = 0.05) and overall received higher doses of ketorolac and acetaminophen. Control patients were more likely to have received neuraxial morphine (78% vs. 90%, p = 0.04) and received higher doses of ibuprofen. In unadjusted analysis, there was no significant difference in morphine milligram equivalent consumption 0-24 h postoperatively between gabapentin (55 mg [IQR 26,84]) and control (53 mg [IQR 28,75]) groups (p = 0.38). After controlling for potential confounders, there remained no significant effect of gabapentin administration (overall effect p = 0.99). Opioid consumption and pain scores were also not significantly different at any other time points.

CONCLUSIONS

In parturients receiving chronic buprenorphine, inclusion of gabapentin in a multimodal analgesic regimen was not associated with lower opioid consumption or pain scores during the first 72 h after cesarean delivery. Prospective randomized studies are needed to confirm these findings.

The Impact of Functional Dependence and Related Surgical Complications on Postoperative Mortality

PURPOSE

Functional dependency is a known determinant of surgical risk. To enhance our understanding of the relationship between dependency and adverse surgical outcomes, we studied how postoperative mortality following a surgical complication was impacted by preoperative functional dependency.

METHODS

We explored a historical cohort of 6,483,387 surgical patients within the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP). All patients ≥ 18 years old within the ACS-NSQIP from 2007 to 2017 were included.

RESULTS

There were 6,222,611 (96.5%) functionally independent, 176,308 (2.7%) partially dependent, and 47,428 (0.7%) totally dependent patients. Within 30 days postoperatively, 57,652 (0.9%) independent, 15,075 (8.6%) partially dependent, and 10,168 (21.4%) totally dependent patients died. After adjusting for confounders, increasing functional dependency was associated with increased odds of mortality (Partially Dependent OR: 1.72, 99% CI: 1.66 to 1.77; Totally Dependent OR: 2.26, 99% CI: 2.15 to 2.37). Dependency also significantly impacted mortality following a complication; however, independent patients usually experienced much stronger increases in the odds of mortality. There were six complications not associated with increased odds of mortality. Model diagnostics show our model was able to distinguish between patients who did and did not suffer 30-day postoperative mortality nearly 96.7% of the time.

CONCLUSIONS

Within our cohort, dependent surgical patients had higher rates of comorbidities, complications, and odds of 30-day mortality. Preoperative functional status significantly impacted the level of postoperative mortality following a complication, but independent patients were most affected.

Association of Delirium during Critical Illness With Mortality: Multicenter Prospective Cohort Study

BACKGROUND

The temporal association of delirium during critical illness with mortality is unclear, along with the associations of hypoactive and hyperactive motoric subtypes of delirium with mortality. We aimed to evaluate the relationship of delirium during critical illness, including hypoactive and hyperactive motoric subtypes, with mortality in the hospital and after discharge up to 1 year.

METHODS

We analyzed a prospective cohort study of adults with respiratory failure and/or shock admitted to university, community, and Veterans Affairs hospitals. We assessed patients using the Richmond Agitation-Sedation Scale and the Confusion Assessment Method for the intensive care unit (ICU) and defined the motoric subtype according to the corresponding Richmond Agitation-Sedation Scale if delirium was present. We used Cox proportional hazard models, adjusted for baseline characteristics, coma, and daily hospital events, to determine whether delirium on a given day predicted mortality the following day in patients in the hospital and also to determine whether delirium presence and duration predicted mortality after discharge up to 1 year in patients who survived to hospital discharge. We performed similar analyses for hypoactive and hyperactive subtypes of delirium.

RESULTS

Among 1040 critically ill patients, 214 (21%) died in the hospital and 204 (20%) died out-of-hospital by 1 year. Delirium was common, occurring in 740 (71%) patients for a median (interquartile range [IQR]) of 4 (2-7) days. Hypoactive delirium occurred in 733 (70%) patients, and hyperactive occurred in 185 (18%) patients, with a median (IQR) of 3 (2-7) days and 1 (1-2) days, respectively. Delirium on a given day (hazard ratio [HR], 2.87; 95% confidence interval [CI], 1.32-6.21; P = .008), in particular the hypoactive subtype (HR, 3.35; 95% CI, 1.51-7.46; P = .003), was independently associated with an increased risk of death the following day in the hospital. Hyperactive delirium was not associated with an increased risk of death in the hospital (HR, 4.00; 95% CI, 0.49-32.51; P = .19). Among hospital survivors, neither delirium presence (HR, 1.01; 95% CI, 0.82-1.24; P = .95) nor duration (HR, 0.99; 95% CI, 0.97-1.01; P = .56), regardless of motoric subtype, was associated with mortality after hospital discharge up to 1 year.

CONCLUSIONS

Delirium during critical illness is associated with nearly a 3-fold increased risk of death the following day for patients in the hospital but is not associated with mortality after hospital discharge. This finding appears primarily driven by the hypoactive motoric subtype. The independent relationship between delirium and mortality occurs early during critical illness but does not persist after hospital discharge.

Impact of an Asynchronous Spaced Education Learning Intervention on Emergency Medicine Clinician Opioid Prescribing

Introduction

Opioid prescribing has contributed to the opioid crisis and education has focused on improved opioid stewardship. We aimed to evaluate the impact of an asynchronous high-quality education to change emergency medicine (EM) clinician opioid prescribing.

Methods

We conducted a retrospective cohort study of a spaced-education intervention in EM clinicians who work at an urban, university-affiliated academic medical center emergency department. We developed opioid prescribing educational content and investigated whether prescriber participation in a novel asynchronous educational program, QuizTime, was associated with a change in EM clinician opioid prescribing practices and whether those prescribing practice changes would be maintained. The primary outcome was the frequency of opioid prescriptions by attributable emergency department discharges. We compared the frequency during the post-intervention period, 24 months following QuizTime education (July 2018 - June 2020) to the baseline period (November 2016 - March 2018). The secondary outcomes were total morphine milligram equivalent (MME) and the number of tablets dispensed per prescription. We analyzed the outcomes by EM clinicians’ level of participation in QuizTime education.

Results

During the study period, there was an overall reduction in opioid prescribing per attributable emergency department discharge (p < 0.001). Among the 45 prescribers who enrolled in QuizTime, there was a significant reduction of 4.3 (95% CI: 3.9, 4.6, p < 0.001) opioid prescriptions per 100 ED discharges in the post-intervention period compared to baseline. Among the 11 non-enrollees, there was a significant reduction of 2.4 (95% CI: 1.7, 3.1, p < 0.001) opioid prescriptions per 100 emergency department discharges in the post-intervention period compared to baseline. The prescribers enrolled in QuizTime had a significantly larger reduction in prescriptions compared to those who did not enroll (p < 0.001). A decreasing trend of total MME and the number of tablets dispensed was observed (p < 0.001). However, there was insufficient evidence to show a reduction in the number of tablets dispensed or MME per day.

Conclusion

EM clinician participation in the QuizTime Pain Management educational program was associated with a nearly two-fold decrease in opioid prescriptions per emergency department discharge compared to peers who chose not to enroll.

Delirium Variability is Influenced by the Sound Environment (DEVISE Study): How Changes in the Intensive Care Unit soundscape affect delirium incidence

Quantitative data on the sensory environment of intensive care unit (ICU) patients and its potential link to increased risk of delirium is limited. We examined whether higher average sound and light levels in ICU environments are associated with delirium incidence. Over 111 million sound and light measurements from 143 patient stays in the surgical and trauma ICUs were collected using Quietyme® (Neshkoro, Wisconsin) sensors from May to July 2018 and analyzed. Sensory data were grouped into time of day, then normalized against their ICU environments, with Confusion Assessment Method (CAM-ICU) scores measured each shift. We then performed logistic regression analysis, adjusting for possible confounding variables. Lower morning sound averages (8 am-12 pm) (OR = 0.835, 95% OR CI = [0.746, 0.934], p = 0.002) and higher daytime sound averages (12 pm-6 pm) (OR = 1.157, 95% OR CI = [1.036, 1.292], p = 0.011) were associated with an increased odds of delirium incidence, while nighttime sound averages (10 pm-8 am) (OR = 0.990, 95% OR CI = [0.804, 1.221], p = 0.928) and the ICU light environment did not show statistical significance. Our results suggest an association between the ICU soundscape and the odds of developing delirium. This creates a future paradigm for studies of the ICU soundscape and lightscape.

Evaluation of Noninvasive Respiratory Volume Monitoring in the PACU of a Low Resource Kenyan Hospital

This research aims to evaluate the use of the noninvasive respiratory volume monitor (RVM) compared to the standard of care (SOC) in the Post-Anesthesia Care Unit (PACU) of Kijabe Hospital, Kenya. The RVM provides real-time measurements for quantitative monitoring of non-intubated patients. Our evaluation was focused on the incidence of postoperative opioid-induced respiratory depression (OIRD). The RVM cohort (N = 50) received quantitative OIRD assessment via the RVM, which included respiratory rate, minute ventilation, and tidal volume. The SOC cohort (N = 46) received qualitative OIRD assessment via patient monitoring with oxygenation measurements (SpO₂) and physical examination. All diagnosed cases of OIRD were in the RVM cohort (9/50). In the RVM cohort, participants stayed longer in the PACU and required more frequent airway maneuvers and supplemental oxygen, compared to SOC (all p < 0.05). The SOC cohort may have had fewer diagnoses of OIRD due to the challenging task of distinguishing hypoventilation versus OIRD in the absence of quantitative data. To account for the higher OIRD risk with general anesthesia (GA), a subgroup analysis was performed for only participants who underwent GA, which showed similar results. The use of RVM for respiratory monitoring of OIRD may allow for more proactive care.

Quantifying the incidence of clinically significant respiratory depression in women with and without obesity class III receiving neuraxial morphine for post-cesarean analgesia: a retrospective cohort study

BACKGROUND

Obesity is a suspected risk factor for respiratory depression following neuraxial morphine for post-cesarean analgesia, however monitoring guidelines for obese obstetric patients are based on small, limited studies. We tested the hypothesis that clinically significant respiratory depression following neuraxial morphine occurs more commonly in women with body mass index (BMI) ≥40 kg/m² compared with BMI <40 kg/m².

METHODS

We conducted a single-center, retrospective chart review (2006-2017) of obstetric patients with clinically significant respiratory depression following neuraxial morphine, defined as: (1) opioid antagonist administration; (2) rapid response team activation (initiated in April 2010); or (3) tracheal intubation due to a respiratory event. The incidence of respiratory depression was compared between women with BMI ≥40 kg/m² and BMI <40 kg/m².

RESULTS

In total, 11 327 women received neuraxial morphine (n=1945 BMI ≥40 kg/m²; n=9382 BMI <40 kg/m²). Women with BMI ≥40 kg/m² had higher rates of sleep apnea, hypertensive disorders, and magnesium administration. Sixteen cases of clinically significant respiratory depression occurred within seven days postpartum. The incidence did not significantly differ between groups (odds ratio 2.2, 95% CI 0.6 to 6.9, P=0.174). Neuraxial morphine was not deemed causative in any case, however women with BMI ≥40 kg/m² had higher rates of tracheal intubation unrelated to neuraxial morphine (2/1945 vs. 0/9382, P=0.029).

CONCLUSIONS

Respiratory depression in this population is rare. A larger sample (∼75 000) is required to determine whether the incidence is higher with BMI ≥40 kg/m². Tracheal intubation was higher among the BMI ≥40 kg/m² cohort, likely due to more comorbidities.

Motoric Subtypes of Delirium and Long-Term Functional and Mental Health Outcomes in Adults After Critical Illness

OBJECTIVES

Adult ICU survivors that experience delirium are at high risk for developing new functional disabilities and mental health disorders. We sought to determine if individual motoric subtypes of delirium are associated with worse disability, depression, and/or post-traumatic stress disorder in ICU survivors.

DESIGN

Secondary analysis of a prospective multicenter cohort study.

SETTING

Academic, community, and Veteran Affairs hospitals.

PATIENTS

Adult ICU survivors of respiratory failure and/or shock.

INTERVENTIONS

We assessed delirium and level of consciousness using the Confusion Assessment Method-ICU and Richmond Agitation and Sedation Scale daily during hospitalization. We classified delirium as hypoactive (Richmond Agitation and Sedation Scale ≤ 0) or hyperactive (Richmond Agitation and Sedation Scale > 0). At 3- and 12-month postdischarge, we assessed for dependence in activities of daily living and instrumental activities of daily living, symptoms of depression, and symptoms of post-traumatic stress disorder. Adjusting for baseline and inhospital covariates, multivariable regression examined the association of exposure to delirium motoric subtype and long-term outcomes.

MEASUREMENTS AND MAIN RESULTS

In our cohort of 556 adults with a median age of 62 years, hypoactive delirium was more common than hyperactive (68.9% vs 16.8%). Dependence on the activities of daily living was present in 37% at 3 months and 31% at 12 months, whereas dependence on instrumental activities of daily living was present in 63% at 3 months and 56% at 12 months. At both time points, depression and post-traumatic stress disorder rates were constant at 36% and 5%, respectively. Each additional day of hypoactive delirium was associated with higher instrumental activities of daily living dependence at 3 months only (0.24 points [95% CI, 0.07-0.41; p = 0.006]). There were no associations between the motoric delirium subtype and activities of daily living dependence, depression, or post-traumatic stress disorder.

CONCLUSIONS

Longer duration of hypoactive delirium, but not hyperactive, was associated with a minimal increase in early instrumental activities of daily living dependence scores in adult survivors of critical illness. Motoric delirium subtype was neither associated with early or late activities of daily living functional dependence or mental health outcomes, nor late instrumental activities of daily living functional dependence.

Dexmedetomidine, Delirium, and Adverse Outcomes: Analysis of the STS Adult Cardiac Surgery Database

BACKGROUND

We tested the hypothesis that dexmedetomidine was associated with a reduced incidence of postoperative delirium (POD) and adverse outcomes in cardiac surgery patients from the Society of Thoracic Surgeons (STS) Adult Cardiac Surgery Database (ACSD) including the Adult Cardiac Anesthesiology subsection.

METHODS

We identified 55905 patients in the STS ACSD who underwent cardiac surgery between July 2014 and December 2018. Using propensity score weighted regression analysis, we analyzed the effect of intraoperative dexmedetomidine (intraDex) on the primary (POD) and secondary outcomes (highest pain score on day 3 and at discharge, stroke, prolonged ventilation, postoperative intubation/reintubation, additional postoperative hours ventilated, renal failure, atrial fibrillation, and 30-day mortality). In separate propensity score weighted analyses, we examined the effect of postoperative dexmedetomidine (postopDex) on the highest postoperative pain score at discharge and 30-day mortality.

RESULTS

The rate of intraDex use was 25.5% (n=13963), and its administration was associated with increased odds for POD (odds ratio [OR], 1.85; 95% CI, 1.60-2.13), a small higher average pain score on day 3 (difference in mean [MD], 0.08; 95% CI, 0.02 to 0.14), increased odds for postoperative intubation/reintubation (OR, 1.29; 95% CI, 1.12-1.48), and a small lower average pain score at discharge (MD, -0.31; 95% CI, -0.21 to -0.41). PostDex was associated with a small higher average pain score at discharge (MD, 0.27, 95% CI, 0.21 to 0.34), and higher odds for 30-day mortality (OR, 1.25, 95% CI, 1.07-1.46).

CONCLUSIONS

In this registry of cardiac surgical patients dexmedetomidine administration was associated with POD and adverse outcomes.

Reliability of simulation-based assessment for practicing physicians: performance is context-specific

INTRODUCTION

Even physicians who routinely work in complex, dynamic practices may be unprepared to optimally manage challenging critical events. High-fidelity simulation can realistically mimic critical clinically relevant events, however the reliability and validity of simulation-based assessment scores for practicing physicians has not been established.

METHODS

Standardised complex simulation scenarios were developed and administered to board-certified, practicing anesthesiologists who volunteered to participate in an assessment study during formative maintenance of certification activities. A subset of the study population agreed to participate as the primary responder in a second scenario for this study. The physicians were assessed independently by trained raters on both teamwork/behavioural and technical performance measures. Analysis using Generalisability and Decision studies were completed for the two scenarios with two raters.

RESULTS

The behavioural score was not more reliable than the technical score. With two raters > 20 scenarios would be required to achieve a reliability estimate of 0.7. Increasing the number of raters for a given scenario would have little effect on reliability.

CONCLUSIONS

The performance of practicing physicians on simulated critical events may be highly context-specific. Realistic simulation-based assessment for practicing physicians is resource-intensive and may be best-suited for individualized formative feedback. More importantly, aggregate data from a population of participants may have an even higher impact if used to identify skill or knowledge gaps to be addressed by training programs and inform continuing education improvements across the profession.

Prevalence of burnout and its relationship to health status and social support in more than 1000 subspecialty anesthesiologists

BACKGROUND

Physician burnout may be at 'epidemic' proportions due to factors associated with modern healthcare practice and technology. Practice attributes vary appreciably among subspecialists. Understanding burnout incidence and its associated factors could illuminate potential causes and interventions. We evaluated burnFout, mental and physical health, and social support and coping skills in acute and chronic pain physicians and pediatric and cardiac anesthesiologists.

METHODS

We administered the Maslach Burnout Inventory Human Services Survey (MBI-HSS), a two-item self-identified burnout measure, the Veterans RAND 12-item Health Survey and the Social Support and Personal Coping Survey to subspecialty society members practicing acute and chronic pain management, pediatric anesthesiology and cardiac anesthesiology. Multivariable regression analysis compared the groups, and adjusted burnout prevalence was compared with an all-physician and an employed general population sample.

RESULTS

Among 1303 participants (response rates 21.6%-35.6% among the subspecialty groups), 43.4% met established burnout criteria (range 30.0%-62.3%). Chronic pain physicians had significantly worse scores (unadjusted) than the other three groups of subspecialty anesthesiologists, the all-physician comparator group and the general population comparator group. Mental health inversely correlated with emotional exhaustion and depersonalization in all groups. Self-identified burnout correlated with the full MBI-HSS (R=0.54; positive predictive value of 0.939 (0.917, 0.955)). Physicians' scores for personal accomplishment were higher than population norms.

CONCLUSIONS

This study provides data on burnout prevalence and associated demographic, health and social factors in subspecialist anesthesiologists. Chronic pain anesthesiologists had significantly greater burnout than the other groups. The self-identified burnout metric performed well and may be an attractive alternative to the full MBI-HSS.

The Attributable Mortality of Postoperative Bleeding Exceeds the Attributable Mortality of Postoperative Venous Thromboembolism

BACKGROUND

Bleeding and venous thromboembolic disease are considered important sources of postoperative morbidity and mortality. Clinically, treatment of these 2 disorders is often competing. We sought to better understand the relative contributions of bleeding and venous thromboembolic disease to postoperative attributable mortality in a national cohort.

METHODS

A retrospective analysis of the 2006-2017 American College of Surgeons' National Surgical Quality Improvement Program (ACS-NSQIP) database was performed to assess the adjusted odds ratio and attributable mortality for postoperative bleeding and venous thromboembolism, adjusted by year.

RESULTS

After adjustment for confounding variables, bleeding exhibited a high postoperative attributable mortality in every year studied. Venous thromboembolism appeared to contribute minimal attributable mortality.

CONCLUSIONS

Bleeding complications are a consistent source of attributable mortality in surgical patients, while the contribution of venous thromboembolic disease appears to be minimal in this analysis. Further studies are warranted to better understand the etiology of this disparity.

Pharmacologic Management of Intensive Care Unit Delirium: Clinical Prescribing Practices and Outcomes in More Than 8500 Patient Encounters

BACKGROUND

Pharmacologic agents are frequently utilized for management of intensive care unit (ICU) delirium, yet prescribing patterns and impact of medication choices on patient outcomes are poorly described. We sought to describe prescribing practices for management of ICU delirium and investigate the independent association of medication choice on key in-hospital outcomes including delirium resolution, in-hospital mortality, and days alive and free of the ICU or hospital.

METHODS

A retrospective study of delirious adult ICU patients at a tertiary academic medical center. Data were obtained regarding daily mental status (normal, delirious, and comatose), pharmacologic treatment, hospital course, and survival via electronic health record. Daily transition models were constructed to assess the independent association of previous day mental status and medication administration on mental status the following day and in-hospital mortality, after adjusting for prespecified covariates. Linear regression models investigated the association of medication administration on days alive and free of the ICU or the hospital during the first 30 days after ICU admission.

RESULTS

We identified 8591 encounters of ICU delirium. Half (45.6%) of patients received pharmacologic treatment for delirium, including 45.4% receiving antipsychotics, 2.2% guanfacine, and 0.84% valproic acid. Median highest Richmond Agitation-Sedation Scale (RASS) score was 1 (0, 1) in patients initiated on medications and 0 (-1, 0) for nonrecipients. Haloperidol, olanzapine, and quetiapine comprised >97% of antipsychotics utilized with 48% receiving 2 or more and 20.6% continued on antipsychotic medications at hospital discharge. Haloperidol and olanzapine were associated with greater odds of continued delirium (odds ratio [OR], 1.48; 95% confidence interval [95% CI], 1.30-1.65; P < .001 and OR, 1.37; 95% CI, 1.20-1.56; P = .003, respectively) and increased hazard of in-hospital mortality (hazard ratio [HR], 1.46; 95% CI, 1.10-1.93; P = .01 and HR, 1.67; 95% CI, 1.14-2.45; P = .01, respectively) while quetiapine showed a decreased hazard of in-hospital mortality (HR, 0.58; 95% CI, 0.40-0.84; P = .01). Haloperidol, olanzapine, and quetiapine were associated with fewer days alive and free of hospitalization (all P < .001). There was no significant association of any antipsychotic medication with days alive and free of the ICU. Neither guanfacine nor valproic acid were associated with in-hospital outcomes examined.

CONCLUSIONS

Pharmacologic interventions for management of ICU delirium are common, most often with antipsychotics, and frequently continued at hospital discharge. These medications may not portend benefit, may introduce additional harm, and should be used with caution for delirium management. Continuation of these medications through hospitalization and discharge draws into question their safety and role in patient recovery.

The effect of adding goal-directed hemodynamic management for elective patients in an established enhanced recovery program for colorectal surgery: results of quasi-experimental pragmatic trial

Background

Recent literature has demonstrated that hemodynamic instability in the intraoperative period places patients at risk of poor outcomes. Furthermore, recent studies have reported that stroke volume optimization and protocolized hemodynamic management may improve perioperative outcomes, especially surgical site infection (SSI), in certain high-risk populations. However, the optimal strategy for intraoperative management of all elective patients within an enhanced recovery program remains to be elucidated.

Methods

We performed a pre-post quasi-experimental study to assess the effect of adding goal-directed hemodynamic therapy to an enhanced recovery program (ERP) for colorectal surgery on SSI and other outcomes. Three groups were compared: “Pre-ERP,” defined as historical control (before enhanced recovery program); “ERP,” defined as enhanced recovery program using zero fluid balance; and “ERP+GDHT,” defined as enhanced recovery program plus goal-directed hemodynamic therapy. Outcomes were obtained through our National Surgical Quality Improvement Program participation.

Results

A total of 623 patients were included in the final analysis (Pre-ERP = 246, ERP = 140, and ERP + GDHT = 237). Demographics and baseline clinical characteristics were balanced between groups. We did not observe statistically significant differences in SSI or composite complication rates in unadjusted or adjusted analysis. There was no evidence of association between study group and 30-day readmission. American Society of Anesthesiologists status ≥ 3 and open surgical approach were significantly associated with increased risk of SSI, composite complication, and 30-day readmission (p < 0.05 for all) in all groups.

Conclusions

There was no evidence that addition of goal-directed hemodynamic therapy for all patients in an enhanced recovery program for colorectal surgery affects the risk of SSI, composite complications, or 30-day readmission. Further research is needed to investigate whether there is benefit of goal-directed hemodynamic therapy for select high-risk populations.

Trial registration

NCT03189550. Registered 16 June 2017–Retrospectively registered, https://www.clinicaltrials.gov/ct2/results?cond=&term=NCT03189550&cntry=&state=&city=&dist=

Transition from Private to Academic Anesthesia Provision Changes Process and Patient Centered Outcomes in an Ambulatory Surgery Center

A recurring concern in the discussion of performance of anesthesia practices is that academic practitioners are slower, less efficient, or produce poorer operational outcomes than their private practice counterparts. A simple overnight 'swap' of a private anesthesia practice with an academic anesthesia practice took place in an outpatient surgery center where the case volume, case mix, surgeons, and staff remained the same. Operational and quality measures were analyzed for comparison between the practices over the span of two years. All patients who had a procedure at the outpatient surgery center in the year prior to the takeover and the year after were studied. Post-anesthesia care unit times, hospital transfer data, pain scores at discharge, opioids dispensed, and anesthesia control times were compared over two years. Charts were manually abstracted by non-clinical administrative staff who were unaware of the study hypothesis. Procedure data and clinical outcomes were compared between the two years using standard statistical techniques. After exchange to the academic group, the median (mean) pain score at post-anesthesia care unit (PACU) discharge was reduced from 2 (2.0) to 0 (1.7) (Wilcoxon rank sum test p < 0.001), and the odds of having moderate or severe pain was reduced by 32% (95% CI, 25, 39, p < 0.001) after adjusting for surgery type. The year-on-year average recovery room time was reduced by 13.9 min (95% CI, 12.5, 15.4, p < 0.001) after adjusting for surgery type. There was a significant reduction in hospital transfer rate after changing groups (0.45% vs. 0.07%, Pearson chi square test p = 0.005). Hospital transfer rates, dispensed opioids in PACU, pain scores at discharge, and PACU times were all improved after the conversion from a private practice to an academic one, without a compromise in efficiency or throughput.

Visualization of aggregate perioperative data improves anesthesia case planning: A randomized, cross-over trial

STUDY OBJECTIVE

A challenge in reducing unwanted care variation is effectively managing the wide variety of performed surgical procedures. While an organization may perform thousands of types of cases, privacy and logistical constraints prevent review of previous cases to learn about prior practices. To bridge this gap, we developed a system for extracting key data from anesthesia records. Our objective was to determine whether usage of the system would improve case planning performance for anesthesia residents.

DESIGN

Randomized, cross-over trial.

SETTING

Vanderbilt University Medical Center.

MEASUREMENTS

We developed a web-based, data visualization tool for reviewing de-identified anesthesia records. First year anesthesia residents were recruited and performed simulated case planning tasks (e.g., selecting an anesthetic type) across six case scenarios using a randomized, cross-over design after a baseline assessment. An algorithm scored case planning performance based on care components selected by residents occurring frequently among prior anesthetics, which was scored on a 0-4 point scale. Linear mixed effects regression quantified the tool effect on the average performance score, adjusting for potential confounders.

MAIN RESULTS

We analyzed 516 survey questionnaires from 19 residents. The mean performance score was 2.55 ± SD 0.32. Utilization of the tool was associated with an average score improvement of 0.120 points (95% CI 0.060 to 0.179; p < 0.001). Additionally, a 0.055 point improvement due to the "learning effect" was observed from each assessment to the next (95% CI 0.034 to 0.077; p < 0.001). Assessment score was also significantly associated with specific case scenarios (p < 0.001).

CONCLUSIONS

This study demonstrated the feasibility of developing of a clinical data visualization system that aggregated key anesthetic information and found that the usage of tools modestly improved residents' performance in simulated case planning.

Effect of Regional Analgesia Techniques on Opioid Consumption and Length of Stay After Thoracic Surgery

BACKGROUND

We examined how intercostal nerve block (ICNB) with standard bupivacaine and ICNB with extended-release liposomal bupivacaine, compared with thoracic epidural analgesia (TEA), were associated with postoperative opioid pain medication consumption and hospital length of stay (LOS) after thoracic surgery.

METHODS

We studied 1935 patients who underwent thoracic surgery between January 1, 2010, and November 30, 2017, at a tertiary academic center. Primary and secondary outcomes were postoperative opioid consumption expressed as morphine milligram equivalents (MMEs) at 24, 48, and 72 hours after surgery, the LOS, and total MME consumption from surgery to discharge.

RESULTS

Of these patients, 888 (45.9%) received TEA, 730 (37.7%) ICNB with standard bupivacaine, 127 (6.6%) ICNB with liposomal bupivacaine, and 190 (9.8%) no regional analgesia. Compared with epidural analgesia, in 2017, ICNB liposomal bupivacaine provided similar pain control in terms of MME consumption at 24 and 72 hours, but decreased MME consumption at 48 hours (odds ratio [OR] = 0.33; confidence interval [CI] = 0.14-0.81) and at discharge (OR = 0.28; CI = 0.12-0.68) and was associated with a higher likelihood for a shorter LOS (hazard ratio = 3.46; CI = 2.42-4.96). Compared with TEA, ICNB with standard bupivacaine and no regional analgesia use showed varying impact on MME consumption between 24 and 72 hours after surgery, and their use was not associated with a significantly reduced MME consumption at discharge but with a shorter hospital LOS.

CONCLUSIONS

Multimodal analgesia involving regional anesthetic alternatives to TEA could help manage postoperative pain in thoracic surgery patients.

Peak Serum Chloride and Hyperchloremia in Patients Undergoing Cardiac Surgery Is Not Explained by Chloride-Rich Intravenous Fluid Alone: A Post-Hoc Analysis of the LICRA Trial

OBJECTIVES

With the exception of 0.9% saline, little is known about factors that may contribute to increased serum chloride concentration (S_Cl^-) in patients undergoing cardiac surgery. For the present study, the authors sought to characterize the association between administered chloride load from intravenous fluid and other perioperative variables, with peak perioperative S_Cl^-.

DESIGN

Secondary analysis of data from a previously published controlled clinical trial in which patients were assigned to a chloride-rich or chloride-limited perioperative fluid strategy (NCT02020538).

SETTING

Academic medical center.

PARTICIPANTS

The study comprised 1,056 adult patients with normal preoperative S_Cl^- undergoing cardiac surgery.

INTERVENTIONS

None MEASUREMENTS AND MAIN RESULTS: Peak perioperative S_Cl^- and hyperchloremia, defined as peak S_Cl^- >110 mmol/L, were selected as co-primary endpoints. Regression modeling identified factors independently associated with these endpoints. Mean (standard deviation) peak perioperative S_Cl^- was 114 (5) mmol/L, and hyperchloremia occurred in 824 (78.0%) of the cohort. In addition to administered volume of 0.9% saline, multivariate linear and logistic regression modeling consistently associated preoperative S_Cl^- (regression coefficient 0.5; 95% confidence interval [CI] 0.4-0.6 mmol/L; odds ratio 1.60; 95% CI 1.41-1.82 per 1 mmol/L increase) and cardiopulmonary bypass duration (regression coefficient 0.1; 95% CI 0.1-0.2 mmol/L; odds ratio 1.12; 95% CI 1.06-1.19 per 10 minutes) with both co-primary outcomes. Multivariate modeling only explained approximately 50% of variability in peak S_Cl^-.

CONCLUSIONS

The present study's data identified an association for both 0.9% saline administration and other nonfluid variables with peak perioperative S_Cl^- and hyperchloremia. Stand-alone strategies to limit administration of chloride-rich intravenous fluid may have limited ability to prevent hyperchloremia in this setting.