Gender Differences With Ibutilide Effectiveness and Safety in Cardioversion of Atrial Fibrillation

INTRODUCTION

Few studies have examined the use of ibutilide in noncardiac surgical populations. Our study considered the effectiveness and safety of ibutilide in cardioversion of atrial fibrillation (AF) in medical and surgical intensive care patients.

METHODS

A retrospective chart review was performed for patients with a confirmed diagnosis of AF who were hemodynamically stable and received ibutilide after the initial diagnosis. Patients were administered 1 mg of ibutilide fumarate intravenous for 10 min with a second dose administered if AF persisted after 30 min. Patients were pretreated with intravenous magnesium sulfate if their blood magnesium level was <2 mg/dL.

RESULTS

Fifty seven total female patients and 99 male patients received ibutilide. Females had an 88% conversion rate to normal sinus rhythm (NSR) compared to 68% in males (P = 0.008). A 70% successful return to NSR was observed in patients from all groups pretreated with magnesium sulfate (P = 0.045). One year after discharge, 74% of the patients stayed in the NSR.

CONCLUSIONS

Within our population, pretreatment with magnesium sulfate followed by ibutilide was associated with increased conversion to NSR. Additionally, we noted that females had a higher conversion rate to NSR compared to males, regardless of whether they were pretreated with magnesium sulfate.

Accuracy of an Artificial Intelligence Chatbot's Interpretation of Clinical Ophthalmic Images

Importance

Ophthalmology is reliant on effective interpretation of multimodal imaging to ensure diagnostic accuracy. The new ability of ChatGPT-4 (OpenAI) to interpret ophthalmic images has not yet been explored.

Objective

To evaluate the performance of the novel release of an artificial intelligence chatbot that is capable of processing imaging data.

Design, Setting, and Participants

This cross-sectional study used a publicly available dataset of ophthalmic cases from OCTCases, a medical education platform based out of the Department of Ophthalmology and Vision Sciences at the University of Toronto, with accompanying clinical multimodal imaging and multiple-choice questions. Across 137 available cases, 136 contained multiple-choice questions (99%).

Exposures

The chatbot answered questions requiring multimodal input from October 16 to October 23, 2023.

Main Outcomes and Measures

The primary outcome was the accuracy of the chatbot in answering multiple-choice questions pertaining to image recognition in ophthalmic cases, measured as the proportion of correct responses. χ2 Tests were conducted to compare the proportion of correct responses across different ophthalmic subspecialties.

Results

A total of 429 multiple-choice questions from 136 ophthalmic cases and 448 images were included in the analysis. The chatbot answered 299 of multiple-choice questions correctly across all cases (70%). The chatbot's performance was better on retina questions than neuro-ophthalmology questions (77% vs 58%; difference = 18%; 95% CI, 7.5%-29.4%; χ21 = 11.4; P < .001). The chatbot achieved a better performance on nonimage-based questions compared with image-based questions (82% vs 65%; difference = 17%; 95% CI, 7.8%-25.1%; χ21 = 12.2; P < .001).The chatbot performed best on questions in the retina category (77% correct) and poorest in the neuro-ophthalmology category (58% correct). The chatbot demonstrated intermediate performance on questions from the ocular oncology (72% correct), pediatric ophthalmology (68% correct), uveitis (67% correct), and glaucoma (61% correct) categories.

Conclusions and Relevance

In this study, the recent version of the chatbot accurately responded to approximately two-thirds of multiple-choice questions pertaining to ophthalmic cases based on imaging interpretation. The multimodal chatbot performed better on questions that did not rely on the interpretation of imaging modalities. As the use of multimodal chatbots becomes increasingly widespread, it is imperative to stress their appropriate integration within medical contexts.

Two-year outcomes of different subretinal fluid drainage techniques during vitrectomy for fovea-off rhegmatogenous retinal detachments: ELLIPSOID-2 Study

BACKGROUND

The purpose of the study is to compare visual acuity, complications and outer retinal integrity following subretinal fluid (SRF) drainage from the peripheral retinal breaks (PRBs) versus posterior retinotomy (PR) versus perfluorocarbon liquid (PFCL) for macula-off rhegmatogenous retinal detachments (RRDs) at 2 years post-surgery.

METHODS

Retrospective analysis of 300 consecutive patients with primary RRD undergoing 23-gauge pars plana vitrectomy with SRF drainage through (1) PRB (n=100), (2) PR (n=100) or (3) with PFCL (n=100). Primary outcomes were visual acuity (best-corrected visual acuity (BCVA)) and complications (cystoid macular oedema (CMO) and epiretinal membrane (ERM)). Secondary outcomes were discontinuity of the external limiting membrane (ELM), ellipsoid zone (EZ) and interdigitation zone (IDZ) at 2 years post-surgery.

RESULTS

Mean (±SD) logMAR BCVA at 24 months was better in the PRB compared with PR and PFCL, with PFCL having the worst BCVA (PRB 0.5±0.6; PR 0.7±0.5; PFCL 0.9±0.7, p=0.001). CMO was higher with PFCL (PRB 29.7%; PR 30.2%; PFCL 45.9%, p=0.0015) and ERM formation was higher in PR (PRB 62.6%; PR 93.0%; PFCL 68.9%, p=0.002). There were no differences in ELM or EZ discontinuity. However, IDZ discontinuity was higher in PFCL (PRB 34%; PR 27%; PFCL 46%, p=0.002) at 2 years.

CONCLUSIONS

Visual acuity was worse and discontinuity of the IDZ and CMO was greater in eyes with PFCL-assisted drainage compared with PRB or PR. Drainage technique may impact long-term visual acuity and photoreceptor integrity.

Tracheal ulcer development from high volume, low-pressure cuffed endotracheal tubes

INTRODUCTION

Iatrogenic injury to the larynx, particularly the vocal cords from prolonged intubation, has been well-studied; however, tracheal injuries are rarely reported. This study investigates the effectiveness of cuffed, high-volume, low-pressure endotracheal tubes in preventing the development of tracheal ulcers in intubated subjects.

METHODS

A retrospective, IRB-approved review was performed on 1355 subjects who underwent percutaneous tracheostomy from 2002 to 2018. The presence and severity of tracheal ulcers were collected using documentation and photos during percutaneous tracheostomy placement. Primary outcome measures included: the length of time on a ventilator until tracheostomy (LOVT), length of hospitalization (LOH), and mortality in relationship to the severity of the tracheal injury. Data was reported as n (%) and median (IQR). The differences in means between groups were analyzed by ANOVA and Chi-square test with an alpha of 0.05.

RESULTS

206 subjects met the inclusion criteria; 65 subjects had an absence of tracheal injury, and 141 subjects developed tracheal ulcers. Subjects with tracheal ulcers were grouped by the following severity scale: no ulcer; mild ulcer (minimal mucosal erosion with exudate); moderate ulcer (mucosal erosion); and severe (tracheal ring exposure). There were no statistically significant differences in age (p = 0.99), gender (p = 0.83), BMI (p = 0.44), LOH (p = 0.88), LOVT (p = 0.93), and mortality (p = 0.306) between subjects with differing severity of ulcers. The average annual incidence of clinically significant ulcers (moderate and severe) was 2.2 %.

CONCLUSIONS

The lack of statistical correlation between the duration of intubation and tracheal ulcer severity, along with a low annual incidence of tracheal ulcers, supports the improved safety of high-volume, low-pressure cylindrical, cuffed endotracheal tubes. This study is among the first to specifically focus on injuries at the level of the cuff and tip of endotracheal tubes with implications in preventive measures and potential product design changes.

PIGMENT EPITHELIAL DETACHMENT THICKNESS AND VARIABILITY AFFECTS VISUAL OUTCOMES IN PATIENTS WITH NEOVASCULAR AGE-RELATED MACULAR DEGENERATION

PURPOSE

To evaluate the impact of pigment epithelial detachment (PED) thickness (i.e., height) and thickness variability on best-corrected visual acuity outcomes in patients with neovascular age-related macular degeneration in the Phase 3 HAWK and HARRIER trials.

METHODS

Optical coherence tomography images from the pooled brolucizumab 6 mg and aflibercept 2 mg arms were analyzed for the maximum PED thickness across the macula at baseline through to week 96. Best-corrected visual acuity outcomes were compared in patients with different PED thickness and variability cut-off thresholds.

RESULTS

Greater PED thickness at baseline or at week 12 was associated with lower mean best-corrected visual acuity gain from baseline to week 96 (baseline PED ≥200 µ m: +4.6 letters; <200 µ m: +7.0 letters; week 12 PED ≥100 µ m: +5.6 letters; <100 µ m: +6.6 letters). Eyes with the largest PED thickness variability from week 12 through week 96 gained fewer letters from baseline at week 96 (≥33 µ m: +3.3 letters; <9 µ m: +6.2 letters). Furthermore, increased PED thickness at week 48 was associated with higher prevalence of intraretinal and subretinal fluid.

CONCLUSION

In this treatment-agnostic analysis, greater PED thickness and PED thickness variability were associated with poorer visual outcomes in patients with neovascular age-related macular degeneration and greater neovascular activity.

Evaluating the long-term biological stability of cytokine biomarkers in ocular fluid samples

PURPOSE

The quality of biological fluid samples is vital for optimal preanalytical procedures and a requirement for effective translational biomarker research. This study aims to determine the effects of storage duration and freeze-thawing on the levels of various cytokines in the human aqueous humour and vitreous samples.

METHODS AND ANALYSIS

Human ocular aqueous humour and vitreous samples were obtained from 25 eyes and stored at -80°C for analysis. All samples were assayed for 27 cytokine biomarker concentrations (pg/mL) using a multiplex assay. Four sample storage durations following sample collection were evaluated (1 week, 3 months, 9 months and 15 months). Additionally, samples underwent up to three freeze-thaw cycles within the study period.

RESULTS

Among the 27 cytokine biomarkers, concentrations of four cytokines (Interleukin (IL)-2, IL-10, IL-12 and platelet-derived growth factor-BB) were significantly decreased by storage duration at all time points, as early as 3 months following sample collection (range of 9%-37% decline between 1 week and 15 months, p<0.001). Freeze-thawing of up to three cycles did not significantly impact the cytokine biomarker concentrations in aqueous humour or vitreous. Separability of patient-specific cytokine biomarker profiles in the principal component analysis remained relatively the same over the 15 months of storage duration.

CONCLUSION

The findings from this study suggest that several intraocular cytokine biomarkers in human aqueous humour and vitreous samples may be susceptible to degradation with long-term storage, as early as 3 months after collection. The overall patient-specific cytokine biomarker profiles are more stable than concentrations of individual cytokines. Future studies should focus on developing guidelines for optimal and standardised sample handling methods to ensure correct research findings about intraocular biomarkers are translated into clinical practice.

Characteristics and Outcomes Associated With Emergent Rectal Foreign Body Management: A Retrospective Cohort Analysis

Background Bedside management and outcomes of rectal foreign bodies remain challenging due to the presentation and complexity of the inserted objects. Injuries, such as perforation of the colon and rectum, are among the most commonly reported complications. However, prior studies are unclear regarding the setting in which the complication rates may be minimized. This study aimed to assess whether there was a statistically significant difference among the various extraction methods with regard to complications in the emergency department and operating room. Materials and methods This was a retrospective study of all cases of rectal foreign bodies that were removed in the emergency department at a large county hospital between 1/1/2010 and 12/31/2020. Patients included in this study were adults who were evaluated and treated in the emergency department. Results A total of 78 patients were included in the final analysis. More than half (51.3%, n=40) of the patients were successfully treated in the emergency department. Compared with the emergency department, patients in the operating room were more likely to undergo exploratory laparotomy and colectomy (0% vs. 31.6%, p<0.0001), undergo general anesthesia (84.2% vs. 0%, p<0.0001), have higher complication rates (21% vs. 0%, p=0.0021), and have a longer hospital length of stay (median=1 vs. 0, p<0.0001). Conclusion This study revealed a >50% success rate of rectal foreign body removal in the emergency department without any reported complications. To improve the success rate of bedside retrieval and decrease complications, physicians need to be vigilant, communicative, and compassionate about their evaluations and clinical methodology.

Persistent subfoveal fluid in pneumatic retinopexy versus pars plana vitrectomy for rhegmatogenous retinal detachment: posthoc analysis of the PIVOT randomised trial

PURPOSE

To assess the incidence of persistent subfoveal fluid (PSFF) in pneumatic retinopexy (PnR) versus pars plana vitrectomy (PPV) following rhegmatogenous retinal detachment (RRD) repair and to determine its association with functional outcomes.

METHODS

Posthoc analysis of the PIVOT randomised trial. Eyes with gradable en face and cross-sectional spectral-domain optical coherence tomography (SD-OCT) scans at 1-2 months postoperatively were included. Primary outcome was the proportion of patients with PSFF following PnR versus PPV at 1-2 months postoperatively. Secondary outcomes included association of PSFF with Early Treatment Diabetic Retinopathy Study (ETDRS) letter score at 3, 6 and 12 months and metamorphopsia score (MCHARTs) at 12 months.

RESULTS

Of 176 participants enrolled in PIVOT, 158 (89.8%) had gradable SD-OCT scans. Intergrader agreement was 0.870 (Cohen's kappa). The incidence of PSFF was 16% (13/81) following PnR and 10.4% (8/77) following PPV (p=0.298; OR=1.65, 95% CI 0.64 to 4.23). Median ETDRS score at 3 months postoperatively between eyes with and without PSFF was 71 (IQR=58-78) and 78 (IQR=70-84), respectively (difference=7 letters, p=0.037), with no significant difference at subsequent 6-month and 12-month visits. Median metamorphopsia scores in patients with versus without PSFF were: horizontal: 0.1 (IQR=0-0.3) vs 0 (IQR=0-0.2) (difference=0.1, p=0.228) and vertical: 0.25 (IQR=0-0.4) vs 0 (IQR=0-0.2) (difference=0.25, p=0.148), respectively.

CONCLUSIONS

There was no significant difference in the incidence of PSFF in eyes undergoing PnR versus PPV for RRD. The presence of PSFF at 1-2 months postoperatively was associated with worse ETDRS letter score at 3 months, but there was no difference at 1 year.

TRIAL REGISTRATION NUMBER

NCT01639209.

Variability of Replicates of Intraocular Inflammatory Biomarkers in Ocular Fluid Samples Analyzed with Multiplex Assays

Purpose

Certain factors such as instrumental and sample processing errors may contribute to variability of ocular biofluid samples when they are run as replicates with multiplex assays. There is a paucity of literature on the variability of replicates in multiplex assays. This study aims to evaluate whether there is significant variability in replicate analyses of multiplex assays.

Methods

A total of 152 human ocular biofluid samples (51 aqueous humor and 101 vitreous) were collected and assayed for 27 cytokine biomarker concentrations (pg/mL). Samples were evaluated as replicates (duplicate analysis) at four different time points. Statistical methods including paired samples t-test, 3-way ANOVA, intraclass correlation coefficient (ICC; <0.5-0.75=poor-moderate, 0.75->0.90 =good-excellent reliability), and coefficients of variation (CV) were employed to evaluate for statistical significance, with Bonferroni corrected P=0.002.

Results

Among the 4104 biomarker replicate assays for aqueous humor and vitreous, two analytes (PDGF-BB and IL-7) had a statistically significant difference between the sampled concentrations of the replicates in vitreous samples (mean (diff)=2.05, P<0.001, mean (diff)=1.56, P<0.001, respectively). Majority of the ICC values fell within the good-excellent range (86% of samples) with a minority falling in the poor-moderate range (14% of samples). More variability was noted in the vitreous humour, with five analytes (IL-2, IL-10, IL-12(p70), IL-13, IL-17) demonstrating an average ICC of less than 0.5. The CV calculated for each set of replicates suggested that 93% of replicates had an acceptable level of quantitative assay variability (CV<20%).

Conclusion

This study demonstrates that the analysis of most biomarkers in ocular fluids may not require the use of replicates. However, certain analytes such as PDGF-BB and IL-7 may require the use of replicates to ensure reliable results. Caution should be taken when applying these findings to other laboratory settings as our study was conducted by an experienced technician using a standardized protocol. In less standardized settings, replicates may be required in order to ensure accuracy of results. These findings may guide researchers with the design of their studies on ophthalmic biomarker analysis.

Comparative assessment of subretinal hyper-reflective material in patients treated with brolucizumab versus aflibercept in HAWK and HARRIER

PURPOSE

Post hoc analysis of the phase III HAWK and HARRIER studies to compare the reductions in subretinal hyper-reflective material (SHRM) thickness following brolucizumab 6 mg or aflibercept 2 mg treatment and to assess SHRM thickness and thickness variability as a potential biomarker of visual outcomes in patients with neovascular age-related macular degeneration (nAMD).

METHODS

Optical coherence tomography images from the brolucizumab (n=700) and aflibercept (n=696) arms were analysed for the maximum SHRM thickness across the macula over 96 weeks. In a pooled treatment-agnostic analysis, the effect of week 12 SHRM thickness and SHRM thickness variability on best-corrected visual acuity (BCVA) through week 96 were also assessed.

RESULTS

Brolucizumab was associated with numerically higher percentage reductions from baseline in SHRM thickness versus aflibercept in all patients (week 96: 54.4% vs 47.6%, respectively) and also in the matched subgroups with disease activity at week 16 (week 96: 51.6% vs 33.8%, respectively). In eyes with lower SHRM measurements at week 12, mean BCVA gains from baseline were higher at week 96 (<200 µm, +6.47 Early Treatment Diabetic Retinopathy Study letters; ≥200 µm, +3.10 letters). Eyes with the lowest SHRM thickness variability from week 12 to week 96 showed the greatest mean BCVA gains from baseline (week 96: <12 µm, +7.42 letters; >71 µm, -2.95 letters).

CONCLUSIONS

In HAWK and HARRIER, greater reductions in maximum SHRM thickness from baseline were observed with brolucizumab compared with aflibercept. Furthermore, the data suggest that SHRM thickness postloading and SHRM thickness variability over time are biomarkers for visual outcomes in patients with nAMD.

Efficacy and safety of anti-vascular endothelial growth agents for the treatment of polypoidal choroidal vasculopathy: A systematic review and meta-analysis

There remains limited agreement regarding the efficacy and safety of different antivascular endothelial growth factor (anti-VEGF) agents for the management of polypoidal choroidal vasculopathy (PCV). Our meta-analysis compares different anti-VEGF agents for PCV treatment. Ovid MEDLINE, EMBASE, and Cochrane Library were systematically searched from January 2000 to July 2022. We included articles comparing the efficacy and safety of different anti-VEGF agents, specifically bevacizumab (BEV), ranibizumab (RAN), aflibercept AFL), and brolucizumab (BRO), for patients with PCV. 10,440 studies were identified, 122 underwent full-text review, and seven were included. One study was a randomized trial, and six were observational studies. Ranibizumab and aflibercept were associated with a similar best-corrected visual acuity (BCVA) at the last visit in three observational studies (P = 0.10), similar retinal thickness at the last visit in two observational studies (P = 0.85). One observational study comparing BEV versus RAN found comparable outcomes for final BCVA, retinal thickness, and polyp regression. One randomized trial on BRO versus AFL found comparable outcomes for improvement in BCVA, while anatomical outcomes favored BRO. The available evidence suggests that final BCVA is comparable across different anti-VEGF agents, however, further investigation is warranted due to paucity of evidence.

Anti-Vascular Endothelial Growth Factor Therapy Regimens for Polypoidal Choroidal Vasculopathy: A Systematic Review

INTRODUCTION

There are no guidelines on the optimal anti-vascular endothelial growth factor (anti-VEGF) monotherapy regimen for patients with polypoidal choroidal vasculopathy (PCV). In this study, we aimed to assess the comparative safety and efficacy of different treatment regimens of anti-VEGF monotherapy for PCV.

METHODS

We conducted a systematic literature search on Ovid MEDLINE, Embase, and Cochrane Library from January 2000 to May 2023 for comparative articles reporting on different treatment regimens of anti-VEGF agents in PCV. Our primary outcomes were the final best-corrected visual acuity (BCVA) and the change in BCVA from baseline. Secondary outcomes were the final retinal thickness (RT), the change in RT from baseline, the rate of polyp closure, and the incidence of adverse events.

RESULTS

A total of 10,440 studies were screened, and seven studies reporting on 636 eyes with PCV at baseline were included in this systematic review. One RCT of 53 eyes found a similar final BCVA, change in BCVA from baseline, final RT, and complete polyp closure rate between a treat-and-extend (T&E) regimen and a bimonthly fixed-dosing regimen of aflibercept. This trial also found superiority of T&E for change in RT from baseline. One observational study of 33 eyes found a similar BCVA at last study observation between a pro re nata (PRN) regimen and bimonthly fixed-dosing regimen of aflibercept. One observational study of 42 eyes found a similar change in BCVA from baseline and complete polyp closure rate between a PRN regimen and bimonthly fixed-dosing regimen of aflibercept. One RCT of 249 eyes found a similar change in BCVA and RT from baseline, as well as polyp closure, between a T&E regimen and fixed 12-week dosing regimen of conbercept. One observational study of 30 eyes found a superiority of T&E aflibercept for change in BCVA and risk of polyp recurrence, compared to a PRN regimen.

CONCLUSION

Overall, there is a paucity of evidence comparing various treatment regimens of anti-VEGF therapy in patients with PCV. This limited evidence suggests that current treatment regimens are similarly efficacious, though T&E aflibercept achieved superior outcomes when compared to bimonthly dosing or PRN in some individual studies. Further trials are needed to confirm or refute these findings.

Prevalence and predictors for being unscreened for diabetic retinopathy: a population-based study over a decade

OBJECTIVE

To determine the population-level predictors for being unscreened for diabetic retinopathy (DR) among individuals with diabetes in a developed country.

DESIGN

A retrospective population-based repeated-cross-sectional study.

PARTICIPANTS

All individuals with diabetes (types 1 and 2) aged ≥20 years in the universal health care system in Ontario were identified in the 2011-2013 and 2017-2019 time periods.

METHODS

The Mantel-Haenszel test was used for the relative risk (RR) comparison of subcategories stratified by the 2 cross-sectional time periods.

RESULTS

A total of 1 145 645 and 1 346 578 individuals with diabetes were identified in 2011-2013 and 2017-2019, respectively. The proportion of patients unscreened for DR declined very slightly from 35% (n = 405 967) in 2011-2013 to 34% (n = 455 027) in 2017-2019 of the population with diabetes (RR = 0.967; 95% CI, 0.964-0.9693; p < 0.0001). Young adults aged 20-39 years of age had the highest proportion of unscreened patients (62% and 58% in 2011-2013 and 2017-2019, respectively). Additionally, those who had a lower income quintile (RR = 1.039; 95% CI, 1.036-1.044; p < 0.0001), were recent immigrants (RR = 1.286; 95% CI, 1.280-1.293; p < 0.0001), lived in urban areas (RR = 1.149; 95% CI, 1.145-1.154; p < 0.0001), had a mental health history (RR = 1.117; 95% CI, 1.112-1.122; p < 0.0001), or lacked a connection to a primary care provider (RR = 1.656; 95% CI, 1.644-1.668; p < 0.0001) had a higher risk of being unscreened.

CONCLUSIONS

This population-based study suggests that over 1 decade, 33% of individuals with diabetes are unscreened for DR, and young age, low income, immigration, residing in a large city, mental health illness, and no primary care access are the main predictors.

Ocular Comorbidities Contributing to Death in the US

This cross-sectional study estimates the prevalence of ocular comorbidities contributing to death in the US, stratified by age, sex, and race and ethnicity.

OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY MORPHOLOGY AFTER RHEGMATOGENOUS RETINAL DETACHMENT REPAIR: ALIGN Post Hoc Analysis

PURPOSE

To compare foveal avascular zone (FAZ) geometric indices using optical coherence tomography angiography (OCTA) in pneumatic retinopexy (PnR) versus pars plana vitrectomy (PPV) for rhegmatogenous retinal detachment (RRD). FAZ morphology was assessed as a possible imaging feature of retinal displacement.

METHODS

This ALIGN post hoc analysis included primary fovea-off RRDs that underwent successful PnR or PPV, and performed OCTA, and fundus autofluorescence at (FAF) 3 months postoperatively at St. Michael's Hospital, Toronto, Canada. FAZ area (mm 2 ), axial ratio, circularity, and roundness were measured, and FAF images were assessed for retinal displacement.

RESULTS

Seventy-two patients were included, 78% (56/72) were male mean age was 60 ± 9 years, and 60% (43/72) were phakic. Sixty-five percent (47/72) and 35% (25/72) underwent PnR and PPV, respectively. The mean baseline logarithm of the minimum angle of resolution visual acuity was 1.49 ± 0.76. FAZ circularity was lower after PPV (0.629 ± 0.120) versus PnR (0.703 ± 0.122); P = 0.016. Sixty-six patients had gradable FAF images. Retinal displacement was present in 29% (19/66), 84.2% (16/19) of which had displacement in the macula. FAZ circularity was lower in eyes with displacement in the macula (0.613 ± 0.110) versus those without displacement (0.700 ± 0.124); P = 0.015. There was a moderate negative correlation between 12-month aniseikonia and FAZ circularity(r = -0.262; P = 0.041).

CONCLUSION

FAZ circularity was lower after PPV and in eyes with retinal displacement in the macula. Circularity was negatively correlated with 12-month aniseikonia scores. FAZ circularity may be another imaging feature to consider postoperatively after RRD repair.

High-dose intravenous versus low-dose oral vitamin C in burn care: potential protective effects in the severely burned: a retrospective cohort study

Antioxidant therapies, such as ascorbic acid may have an important role during the acute phase of burn management. However, there are mixed results on the most effective dose and method of administration of ascorbic acid in burn patients. In this study, we compared the efficacy of intravenously and orally administered ascorbic acid in second-degree burns greater than 20% total-body-surface-area.

Materials and methods

The hospital burn database was used to obtain data on all patients with second-degree or deeper burns of 20% total-body-surface-area or greater. Fourteen patients were selected at random to receive a scheduled dose of 1250 mg intravenous ascorbic acid every 6 h for 72 h. This was considered the high-dose group. During same period, 40 patients received scheduled 500 mg oral ascorbic acid every 6 h for 72 h and this was considered the low-dose group. We gathered sociodemographic and clinical variables associated with ascorbic acid dosing.

Results

In our study, statistically significant variables were fluid requirements (p<0.001), hospital stay (p=0.011), length of time intubated on ventilator (p<0.001), colloids used (p=0.002), and total procedures required (p=0.014). Despite higher modified Baux predicted mortality in the high-dose group (10 patients vs. 24 patients, p=0.026) there was no noted significant association in days until the first infection and mortality rate (p=0.451 and 0.326, respectively).

Conclusions

The calculated modified Baux predicted a higher mortality rate with the higher dosing group, yet this study did not find a mortality difference between the groups. We speculate that high-dose intravenous ascorbic acid may have protective effects in burn resuscitation. This finding may support some previous studies that found that high-dose ascorbic acid may improve clinical outcomes.

High incidence of adult respiratory distress syndrome associated with amphetamine use in the burn population: a retrospective cohort study

A high incidence of adult respiratory distress syndrome (ARDS) is observed in patients with a history of amphetamine use with limited studies addressing this exact topic. The authors sought to understand and compare the clinical features of patients experiencing amphetamine-associated lung injury with features of similar patients naïve to amphetamines, in a population of burn patients. Patients in this population tend to be young with few comorbidities offering a unique opportunity to study the relationship between amphetamine use and ARDS.

Materials and methods

A total of 188 patients age 18 and older with total body surface area (TBSA) between 20 and 60% were sampled over 5 years. To capture the moderate to severe burn population, a lower limit of 20% was chosen while 60% was used as the upper limit to exclude patients likely to die from the burns alone. Patients eligible to be include in the study had to meet the TBSA criteria. Demographic data was ascertained. Patients were placed into two cohorts: the amphetamine positive group (AmPOS), the amphetamine negative group (AmNEG). Key endpoints included hospital mortality, length of ICU stay, development of ARDS, and cardiac output parameters. Nonparametric data was evaluated with the Mann-Whitney test and categorical variables were compared using χ ².

Results

Data from 49 patients with ARDS were collected retrospectively out of the 188 patients in this TBSA range. The incidence of amphetamine abuse in these burn patients is 14.9%. The average age of AmPOS and AmNEG patients was 36 and 34 and the average TBSA of burns in the AmPOS and AmNEG group was 51.8 and 45.2%. The mean onset of ARDS was 2.2 days for the AmPOS versus 3.3 days for the AmNEG (P=0.19). At admission, patients with amphetamine use exhibited less inhalational injury and a lower Acute Physiology and Chronic Health Evaluation II (APACHE II) score. In AmPOS, 64% developed ARDS compared to 19% in AmNEG (P<0.001). Mortality, time on a ventilator, ICU days, packed Red Blood Cell, Fresh Frozen Plasm, platelets transfused, and initial cardiac parameters all were not statistically significant. On the initial date of ARDS diagnosis, there was no statistically significant difference with PaO₂/FiO₂ and compliance (P=0.67), but positive end expiratory pressure requirements was higher in AmPOS (P=0.018).

Conclusions

Amphetamine Use was associated with increased risk of developing ARDS in the burn population. This is despite having a better APACHE II and lower incidence of inhalational injury in the AmPOS group, supporting amphetamine as an independent risk factor for ARDS.

Emergent surgical interventions in noncritical traumatic long bone fractures and lactate monitoring: a retrospective cohort study

Serum lactate levels have been recommended as a standard in guiding resuscitation and management of post-traumatic orthopedic injuries. Studies have suggested an increased incidence of postoperative complications in trauma patients with injury severity scores (ISSs) greater than 18. However, in trauma patients without an elevated ISS, the role of lactate in guiding operative timing has not been explored. This study considers the role of lactate measurement with respect to surgical timing and predicting postoperative complications in trauma patients with long bone fractures and an ISS less than 16.

Materials and methods

A total of 164 patients, ages 18 and above with long bone fractures and ISS less than 16 were sampled in the last 5 years. Demographic data was ascertained. Patients were placed into two cohorts with a serum preoperative lactate greater than or equal to 2.0 mmol/l and a serum preoperative lactate less than 2.0 mmol/l. Key endpoints included hospital mortality, length of hospitalization (LOH), discharge designation, and postoperative complications.

Results

A total of 148 patients had a lactate level less than 2.0 mmol/l and 16 had a lactate greater than or equal to 2.0 mmol/l. There was no significant difference in demographics between these two preoperative lactate groups. There was no statistical difference when considering mortality, discharge designation, LOH, and postoperative complications.

Conclusion

Lactate levels assist providers in guide resuscitative efforts in trauma patients. However, this study finds that preoperative lactate measurements and efforts made to normalize lactate level are not correlated with mortality, LOH, and postoperative complications in trauma patients with an ISS less than 16. This study does not support preoperative lactate normalization in guiding surgical timing.

Prevalence and clinical implications of subretinal fluid in retinal diseases: a real-world cohort study

Background/aims

To characterise the baseline prevalence of subretinal fluid (SRF) and its effects on anatomical and visual acuity (VA) outcomes in diabetic macular oedema (DME) and retinal vein occlusion (RVO) following anti-vascular endothelial growth factor (VEGF).

Methods

This is a retrospective cohort study of 122 DME and 54 RVO patients who were initiated on anti-VEGF therapy with real-world variable dosing. The DME and RVO cohorts were subclassified based on the presence of SRF at presentation. Snellen VA was measured and converted to logarithm of the minimum angle of resolution (LogMAR). Changes in VA and central subfield thickness (CST) were assessed up to 24 months.

Results

SRF was present in 22% and 41% in DME and RVO patients, respectively. In the DME subcohort, eyes with SRF showed an improvement of 0.166 logMAR (1.7 Snellen chart lines) at 12 months and 0.251 logMAR (2.6 Snellen chart lines) at 24 months, which were significantly greater compared with those of the non-SRF group. A significantly greater reduction in CST was noted in the SRF eyes compared with the non-SRF eyes at 3 months and 1 month in the DME and RVO subcohorts, respectively.

Conclusion

Baseline SRF is a good marker for a greater reduction in CST in both DME and RVO, but an improvement in VA associated with SRF may be only noted in DME.

En Face OCT in Diagnosis of Persistent Subretinal Fluid and Outer Retinal Folds after Rhegmatogenous Retinal Detachment Repair

PURPOSE

To evaluate the role of en face OCT as a diagnostic tool for the detection of persistent subretinal fluid (PSRF) and outer retinal folds (ORFs) after successful rhegmatogenous retinal detachment (RRD) repair.

DESIGN

Observational post hoc analysis of 2 prospective surgical trials.

PARTICIPANTS

All patients with gradable (signal strength ≥ 5 and no segmentation error) 6 × 6-mm² macular cube scans obtained using spectral-domain OCT (Carl Zeiss Meditec) between 1 and 2 months after surgery were included in this study.

METHODS

The scans were assessed for the presence or absence of PSRF or ORFs using en face OCT and cross-sectional B scans by 2 masked graders, with any disagreements adjudicated by a third senior masked grader.

MAIN OUTCOME MEASURES

The sensitivity, specificity, and predictive accuracy (using area under the curve [AUC]) of en face OCT were compared with those of cross-sectional OCT, which is considered the gold standard.

RESULTS

Two hundred twenty-three patients were included in this study. The Cohen kappa between the graders in the diagnosis of PSRF and ORFs using en face OCT was 0.84 and 0.86, respectively. The sensitivity of en face OCT was 100% (95% confidence interval [CI], 100%-100%) in the diagnosis of PSRF and 98.8% (95% CI, 96.5%-101.1%) in the diagnosis of ORFs. Similarly, the specificity of en face OCT was 98.7% (95% CI, 96.8%-100.5%) and 84.2% (95% CI, 78.1%-90.2%) in the diagnosis of PSRF and ORFs, respectively. The AUC was 0.99 for PSRF and 0.91 for ORFs.

CONCLUSIONS

En face OCT has good sensitivity, specificity, and predictive accuracy (using AUC) in the diagnosis of PSRF and ORFs. En face OCT is an efficient screening tool for postoperative anatomic abnormalities, such as PSRF and ORFs, after RRD repair.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Effect of high-flow nasal oxygen on hypoxaemia during procedural sedation: a systematic review and meta-analysis

We conducted a systematic review to evaluate the effect of high-flow nasal oxygen and conventional oxygen therapy during procedural sedation amongst adults and children. We searched MEDLINE, EMBASE and CINAHL for randomised controlled trials that reported the effects of high-flow nasal oxygen during procedural sedation. The primary outcome measure was hypoxaemia and the secondary outcomes were minimum oxygen saturation; hypercarbia; requirement for airway manoeuvres; and procedure interruptions. The quality of evidence was assessed using the revised Cochrane risk-of bias tool and grading of recommendations, assessment, development and evaluation (GRADE). Nineteen randomised controlled trials (4121 patients) including three in children were included. Administration of high-flow nasal oxygen reduced hypoxaemia, risk ratio (95%CI) 0.37 (0.24-0.56), p < 0.001; minor airway manoeuvre requirements, risk ratio (95%CI) 0.26 (0.11-0.59), p < 0.001; procedural interruptions, risk ratio (95%CI) 0.17 (0.05-0.53), p = 0.002; and increased minimum oxygen saturation, mean difference (95%CI) 4.1 (2.70-5.50), p < 0.001; as compared with the control group. High-flow nasal oxygen had no impact on hypercarbia, risk ratio (95%CI) 1.24 (0.97-1.58), p = 0.09, I²  = 0%. High-flow nasal oxygen reduced the incidence of hypoxaemia regardless of the procedure involved, degree of fractional inspired oxygen, risk-profile of patients and mode of propofol administration. The evidence was ascertained as moderate for all outcomes except for procedure interruptions. In summary, high-flow nasal oxygen compared with conventional oxygenation techniques reduced the risk of hypoxaemia, increased minimum oxygen saturation and reduced the requirement for airway manoeuvres. High-flow nasal oxygen should be considered in patients at risk of hypoxaemia during procedural sedation.

Optimal Tracheostomy Timing Through Modeling Based on Severity of Vocal Cord Injury

BACKGROUND

Endotracheal intubation is a routinely performed procedure in the ICU. Whereas it is recognized that endotracheal intubation can result in laryngeal and tracheal injury, this study evaluated factors that may affect the incidence of posterior vocal cord ulcers (PVCUs).

METHODS

One thousand three hundred fifty-five patients were retrospectively screened from 2002-2018 that received a tracheostomy with routine bronchoscopy at a single institution. Post tracheostomy operative notes were reviewed and included only if proper visualization of the vocal cords was documented. Primary outcome measures included presence of PVCU, length of time on a ventilator until a tracheostomy, hospital length of stay, and mortality. Stratification of the data focused on the severity of the ulcer (mild, moderate, and severe) and was analyzed using analysis of variance, multivariate analysis, and Kaplan-Meier modeling of PVCU incidence over time.

RESULTS

We enrolled 192 subjects with documentation of vocal cord visualization. Thirty-nine subjects did not have a PVCU, whereas 153 subjects did. A median duration of 9 (interquartile range [IQR] 5-13) d was associated with developing a mild PVCU, whereas individuals intubated for a median of 6 (IQR 4-7) d were ulcer free. Statistical difference between length of time on a ventilator before tracheostomy and the severity of the PVCU seen was significant (P < .001). The Kaplan-Meier model showed that beyond 2 weeks of endotracheal intubation subjects will have > 80% chance of developing a moderate vocal cord ulcer. Whereas by day 7, there is only a 20% chance of developing a moderate ulcer.

CONCLUSIONS

Earlier tracheostomy placement was associated with reduced severity of vocal cord ulcer formation. The Kaplan-Meier model suggests that waiting for 14 d is likely too long and earlier placement of a tracheostomy, within a week, may decrease the morbidity of posterior vocal cord injury.

Evaluation of Subretinal fluid Drainage Techniques during Pars Plana Vitrectomy for Primary Rhegmatogenous Retinal Detachment - ELLIPSOID study

PURPOSE

To compare visual acuity and photoreceptor integrity following vitrectomy (PPV) with drainage from the peripheral retinal break(s) (PRB) vs. posterior retinotomy (PR) vs. perfluorocarbon liquid (PFCL) for macula-off rhegmatogenous retinal detachment (RRD).

DESIGN

Retrospective consecutive interventional comparative clinical study.

METHODS

300 consecutive patients (300 eyes) with primary macula-off RRD underwent 23-gauge PPV with SRF drainage through 1) PRB (n=100), 2) PR (n=100), or 3) with PFCL (n=100). Visual acuity and SD-OCT were performed preoperatively and at 3, 6, and 12 months postoperatively. Primary outcomes were visual acuity and discontinuity of the external limiting membrane, ELM; ellipsoid zone, EZ; interdigitation zone, IDZ; and retinal pigment epithelium, RPE at 1-year.

RESULTS

Baseline characteristics were similar. Single-operation reattachment rates were: PRB 86%; PR 85%; PFCL 83%,p=0.9. Mean(±SD) logMAR visual acuity at 1-year was greater with PRB and PR compared to PFCL (PRB=0.6±0.5;PR=0.7±0.6;PFCL=0.9±0.6,p=0.002). There was an association between drainage technique and discontinuity of the ELM (PRB 26%,PR 24%,PFCL 44%,p=0.001), EZ (PRB 29%,PR 31%,PFCL 49%,p<0.001) and IDZ (PRB 43%,PR 39%,PFCL 56%, p=0.004). There was an association between drainage technique and risk of cystoid macular edema (CME) (PRB 28%,PR 39%,PFCL 46%,p=0.003) and ERM (PRB 64%,PR 90%,PFCL 61%,P<0.001).

CONCLUSIONS

PFCL-assisted drainage is associated with worse visual acuity and greater risk of outer retinal band discontinuity and CME compared with PRB or PR. PR had a greater risk of ERM compared with PRB and PFCL. PRB had the best outcomes overall. Drainage technique may impact long-term anatomic and functional outcomes.

Longitudinal Assessment of Ellipsoid Zone Recovery Using En Face Optical Coherence Tomography After Retinal Detachment Repair

PURPOSE

Suboptimal functional outcomes after rhegmatogenous retinal detachment (RRD) repair may be related to photoreceptor abnormalities, including alterations of the ellipsoid zone (EZ) that may not be apparent on cross-sectional optical coherence tomography (OCT). This study assessed EZ recovery using en face OCT after RRD repair and its association with visual acuity.

DESIGN

Post hoc analysis of a randomized controlled trial.

METHODS

Patients with macula-off RRD were monitored at 3, 6, 12, and 24 months postoperatively and annually thereafter. En face OCT of the EZ slab were analyzed. Hyporeflective areas were colocalized with EZ abnormalities on cross-sectional OCT B-scans and measured by 2 masked graders. Primary outcome was change in area of EZ hyporeflectivity from 3 to 24 months, and its association with Early Treatment Diabetic Retinopathy Study (ETDRS) visual acuity recovery was also assessed.

RESULTS

In total, 271 images of 61 patients were assessed. Mean area of hyporeflectivity significantly decreased from 3 to 24 months (-2.98 mm²; 95% CI, 1.82-4.13 mm²; P < .0001), with further reductions up to 4 years. Linear regression revealed an association between change in hyporeflective area and change in the ETDRS letter score from 3 to 24 months (β = -0.31, P = .009, R² = 14.8%) and between duration of macula-off and change in hyporeflective area from 3 to 24 months (β = -0.37, P = .018, R² = 13.7%).

CONCLUSIONS

En face OCT provides a novel biomarker for visualizing and quantifying EZ recovery after RRD repair that is associated with ETDRS visual acuity recovery. A steady decline in the area of EZ hyporeflectivity was observed over many years with delayed recovery in patients with longer duration of macula-off.

The Role of the Urinary Bladder in the Diagnosis of Abdominal Compartment Syndrome: A Prospective Study in Trauma Patients

Purpose The aim of this study was to evaluate the accuracy of bladder pressures in the diagnosis and management of abdominal compartment syndrome (ACS). Methods After Institutional Review Board (IRB) approval, nine operative abdominal trauma patients were prospectively studied over an 18-month period. Bladder pressures were compared to pressures obtained from intra-operatively placed electronic transducer located in the pelvis. Statistical analysis was performed using methods described by Bland and Altman. Results A Bland-Altman plot was used to assess the differences between bladder and transducer pressures. There was little agreement between the two methods at low (10-15 mmHg) and high (30-70 mmHg) pressures. At higher pressures, there was a notable difference between these two types of pressure. No patients required repeated operation. One patient died from severe traumatic brain injury. Conclusion Measurements obtained from the urinary bladder did not agree well with those obtained from within the peritoneal cavity. Furthermore, abdominal pressures greater than 20 mmHg did not show signs of ACS in this selected population, raising doubts about the utility of using abdominal pressures alone in the management of ACS.

Diagnostic accuracy of teleretinal screening for detection of diabetic retinopathy and age-related macular degeneration: a systematic review and meta-analysis

Objective

To evaluate the diagnostic accuracy of teleretinal screening compared with face-to-face examination for detection of diabetic retinopathy (DR) and age-related macular degeneration (AMD).

Methods and analysis

This study adhered to the Preferred Reporting Items for a Systematic Review and Meta-analysis of Diagnostic Test Accuracy Studies (PRISMA-DTA). A comprehensive search of OVID MEDLINE, EMBASE and Cochrane CENTRAL was performed from January 2010 to July 2021. QUADAS-2 tool was used to assess methodological quality and applicability of the studies. A bivariate random effects model was used to perform the meta-analysis. Referrable DR was defined as any disease severity equal to or worse than moderate non-proliferative DR or diabetic macular oedema (DMO).

Results

28 articles were included. Teleretinal screening achieved a sensitivity of 0.91 (95% CI: 0.82 to 0.96) and specificity of 0.88 (0.74 to 0.95) for any DR (13 studies, n=7207, Grading of Recommendations, Assessment, Development and Evaluation (GRADE) low). Accuracy for referrable DR (10 studies, n=6373, GRADE moderate) was lower with a sensitivity of 0.88 (0.81 to 0.93) and specificity of 0.86 (0.79 to 0.90). After exclusion of ungradable images, the specificity for referrable DR increased to 0.95 (0.90 to 0.98), while the sensitivity remained nearly unchanged at 0.85 (0.76 to 0.91). Teleretinal screening achieved a sensitivity of 0.71 (0.49 to 0.86) and specificity of 0.88 (0.85 to 0.90) for detection of AMD (three studies, n=697, GRADE low).

Conclusion

Teleretinal screening is highly accurate for detecting any DR and DR warranting referral. Data for AMD screening is promising but warrants further investigation.

PROSPERO registration number

CRD42020191994.

Impact of a continuous enhanced cardio-respiratory monitoring pathway on cardio-respiratory complications after bariatric surgery: A retrospective cohort study

STUDY OBJECTIVE

To determine the impact of an enhanced monitoring pathway consisting of continuous postoperative cardio-respiratory monitoring on adverse outcomes after bariatric.

DESIGN

Single-center, retrospective cohort study.

PATIENTS

Adult patients who underwent bariatric surgeries between 2009 and 2016.

INTERVENTIONS

We evaluated the use of an enhanced monitoring pathway consisting of a distant, continuous, non-invasive respiratory monitoring system on postoperative cardio-respiratory complications in patients undergoing bariatric surgery. Treating physicians had the option to assign patients to enhanced monitoring (intervention group) in the postoperative period for suspected or diagnosed OSA or other clinical concerns. The control group had intermittent vital sign checks as per institutional standards.

MEASUREMENTS

The primary outcome was a composite of cardio-respiratory complications (rapid response team activation, intensive care admission, respiratory complications), major adverse cardiac events, and all-cause mortality. The secondary outcome was length of stay (LOS).

MAIN RESULTS

Of 1450 patients, 752 patients received enhanced monitoring (intervention) and 698 patients received standard monitoring (control). Univariate analysis showed that, compared to control, enhanced monitoring was associated with lower odds of composite cardio-respiratory complications (OR: 0.41, 95%CI: 0.32-0.53, p < 0.001) and lower odds of prolonged LOS > 2 days (OR: 0.37, 95% CI: 0.28-0.49, p < 0.001. After adjusting for potential confounders, enhanced monitoring remained associated with a reduction in composite cardio-respiratory complications (OR: 0.64, 95% CI: 0.46-0.88, p = 0.005).

CONCLUSIONS

Our study demonstrates that postoperative enhanced monitoring pathway was associated with a lower incidence of cardio-respiratory composite events, compared to a standard of care, in patients undergoing bariatric surgery. As our results show association rather than causation, future prospective randomized trials are needed to confirm the benefit of enhanced monitoring. Findings of our study add to the existing literature involved in clinical management pathways to reduce the incidence of adverse postoperative outcomes in high-risk patients undergoing inpatient surgeries.

Displacement Following Pneumatic vs Vitrectomy for Retinal Detachment (ALIGN)

This multicenter non-randomized comparative trial demonstrates that PPV is associated with a higher risk of retinal displacement compared to PnR for macula-off rhegmatogenous retinal detachment. Furthermore, retinal displacement is associated with worse aniseikonia.

Deep learning-based plaque quantification from coronary computed tomography angiography: external validation and comparison with intravascular ultrasound

Background

Atherosclerotic plaque quantification from coronary computed tomography angiography (CTA) enables accurate assessment of coronary artery disease burden, progression, and prognosis. However, quantitative plaque analysis is time-consuming and requires high expertise. We sought to develop and externally validate an artificial intelligence (AI)-based deep learning (DL) approach for CTA-derived measures of plaque volume and stenosis severity. We compared the performance of DL to expert readers and the gold standard of intravascular ultrasound (IVUS).

Methods

This was a multicenter study of patients undergoing coronary CTA at 11 sites, with software-based quantitative plaque measurements performed at a per-lesion level by expert readers. AI-based plaque analysis was performed by a DL novel convolutional neural network which automatically segmented the coronary artery wall, lumen, and plaque for the computation of plaque volume and stenosis severity. Using expert measurements as ground truth, the DL algorithm was trained on 887 patients (4,686 lesions). Thereafter, the algorithm was applied to an independent test set of 221 patients (1,234 lesions), which included an external validation cohort of 171 patients from the SCOT-HEART (Scottish Computed Tomography of the Heart) trial as well as 50 patients who underwent IVUS within one month of CTA. We report the performance of AI-based plaque analysis in the independent test set.

Results

Within the external validation cohort, there was excellent agreement between DL and expert reader measurements of total plaque volume (intraclass correlation coefficient [ICC] 0.876), noncalcified plaque volume (ICC 0.869), and percent diameter stenosis (ICC 0.850; all p&lt;0.001). When compared with IVUS, there was excellent agreement for DL total plaque volume (ICC 0.945), total plaque burden (ICC 0.853), minimal luminal area (ICC 0.864), and percent area stenosis (ICC 0.805; all p&lt;0.001); with strong correlation between DL and IVUS for total plaque volume (r=0.915; p&lt;0.001; Figure). The average DL plaque analysis time was 20 seconds per patient, compared with 25–30 minutes taken by experts.

Conclusions

AI-based plaque quantification from coronary CTA using an externally validated DL approach enables rapid measurements of plaque volume and stenosis severity in close agreement with expert readers and IVUS.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): National Heart, Lung, and Blood Institute, United States

Outer Retinal Folds Following Pars Plana Vitrectomy vs Pneumatic Retinopexy for Retinal Detachment Repair: Post Hoc Analysis from PIVOT

PURPOSE

To assess the incidence of post-operative outer retinal folds (ORFs) in pars plana vitrectomy (PPV) vs pneumatic retinopexy (PnR) following rhegmatogenous retinal detachment (RRD) repair and to determine the association of ORFs with functional outcomes at 1 year.

DESIGN

Randomized controlled trial PARTICIPANTS: Patients with primary macula-off RRD meeting PIVOT trial criteria randomly assigned to PPV vs PnR.

METHODS

Post-hoc analysis of the PIVOT trial. Incidence and quantitative morphological features of ORFs were assessed with en face and cross-sectional OCT at 1 month post-operatively by two masked graders. ETDRS letter score and quantitative metamorphopsia were measured at 1 year.

MAIN OUTCOME MEASURES

Proportion of patients with ORFs following PPV vs PnR at 1 month post-operatively. Secondary outcomes include the association of ORFs with visual acuity (ETDRS letter score) and metamorphopsia (M-CHARTS) at 12 months post-operatively.

RESULTS

Eighty-eight of the 176 participants enrolled in PIVOT were macula-off RRD. 94.3% (83/88) of these macula-off eyes had month 1 post-operative OCT scans that were gradable, 93.2% (41/44) in the PPV group and 95.5% (42/44) in the PnR group. The incidence of ORFs formation was 34.1% (14/41) in the PPV group and 14.3% (6/42) in the PnR group (p=0.034). ETDRS letter score at 1 year was 65.7±6.6 letters in patients with ORFs versus 75.1±1.4 letters in those without ORFs (difference=9.4 letters, 95% CI=7.5-11.3, p=0.047). Among patients in the PPV group only, mean ETDRS letter score at 1 year in patients with ORFs was 62.8 ± 24.7 letters compared to 75.4 ± 9.2 letters in patients without ORF formation (difference=12.6 letters, 95% CI=0.05-24.59, p=0.04). Horizontal and vertical metamorphopsia scores were similar in patients with vs without ORFs: horizontal: 0.35 ± 0.12 versus 0.29 ± 0.07 (difference=0.06, 95% CI=0.01-0.11, p=0.69) and vertical: 0.25±0.07 versus 0.29±0.07 (difference=0.04, 95%CI=0-0.08, p=0.60) respectively. There was a negative correlation between the closest distance of the ORFs from the fovea and the vertical metamorphopsia score (r=-0.507, p=0.045).

CONCLUSIONS

There is a greater risk of developing ORFs following PPV compared to PnR for RRD. ORFs at 1 month are associated with significantly worse ETDRS visual acuity letter score at 1 year.

Methicillin-Resistant Staphylococcus aureus-Associated Diarrhea in a Critically Ill Burn Patient

Described in surgical patients after antibiotic use in the 1950s and 1960s, Staphylococcus aureus (S. aureus) enterocolitis is a rare form of nosocomial diarrhea. However, S. aureus is not routinely tested like Clostridium difficile (C. difficile). We report a case of methicillin-resistant S. aureus (MRSA) enterocolitis found on stool culture in a 22-week pregnant female with a previously negative nasal MRSA culture, and a total burn surface area greater than 60%. She also developed necrotizing MRSA pneumonia and bacteremia. After starting broad-spectrum antibiotic for the necrotizing pneumonia with subsequent acute respiratory distress syndrome, the patient exhibited large voluminous diarrhea that tested positive for MRSA and negative for C. difficile in the stool culture. Similar to other reports of high-volume diarrhea, the diarrhea resolved quickly with enteral vancomycin. S. aureus should be considered along with C. difficile during the workup of nosocomial diarrhea, especially with exposure to broad-spectrum antibiotics in the critically ill patient.

Evidence-based Canadian guidelines for tele-retina screening for diabetic retinopathy: recommendations from the Canadian Retina Research Network (CR2N) Tele-Retina Steering Committee

OBJECTIVE

The purpose of this report is to develop a consensus for Canadian national guidelines specific to a tele-medicine approach to screening for diabetic retinopathy (DR) using evidence-based and clinical data.

METHODS

Canadian Tele-Screening Grading Scales for DR and diabetic macular edema (DME) were created primarily based on severity grading scales outlined by the International Clinical Diabetic Retinopathy Disease Severity Scale (ICDR) and the Scottish DR Grading Scheme 2007. Other grading scales used in international screening programs and the clinical expertise of the Canadian Retina Research Network members and retina specialists nationwide were also used in the creation of the guidelines.

RESULTS

National Tele-Screening Guidelines for DR and DME with and without optical coherence tomography (OCT) images are proposed. These outline a diagnosis and management algorithm for patients presenting with different stages of DR and/or DME. General guidelines detailing the requirements for imaged retina fields, image quality, quality control, and follow-up care and the role of visual acuity, pupil dilation, OCT, ultra-wide-field imaging, and artificial intelligence are discussed.

CONCLUSIONS

Tele-retina screening can help to address the need for timely and effective screening for DR, whose prevalence continues to rise. A standardized and evidence-based national approach to DR tele-screening has been proposed, based on DR/DME grading using two 45° image fields or a single widefield or ultra-wide-field image, preferable use of OCT imaging, and a focus on local quality control measures.

Postoperative Photoreceptor Integrity Following Pneumatic Retinopexy vs Pars Plana Vitrectomy for Retinal Detachment Repair: A Post Hoc Optical Coherence Tomography Analysis From the Pneumatic Retinopexy Versus Vitrectomy for the Management of Primary Rhegmatogenous Retinal Detachment Outcomes Randomized Trial

Importance

Pneumatic retinopexy (PnR) is associated with superior visual acuity and reduced vertical metamorphopsia compared with pars plana vitrectomy (PPV) for primary rhegmatogenous retinal detachment (RRD). It is important to determine postoperative photoreceptor integrity with both surgical techniques.

Objective

To compare photoreceptor integrity on spectral domain-optical coherence tomography (SD-OCT) between PnR and PPV at 12 months postoperatively.

Design, Setting, and Participants

Post hoc analysis of the Pneumatic Retinopexy Versus Vitrectomy for the Management of Primary Rhegmatogenous Retinal Detachment Outcomes Randomized Trial (PIVOT) conducted between August 2012 and May 2017 at St Michael's Hospital, Toronto, Ontario, Canada. Primary RRDs with specific criteria were included. Data were analyzed between April and August 2020.

Intervention

Randomization to PnR vs PPV stratified by macular status.

Main Outcomes and Measures

Difference in proportion of patients with discontinuity of the ellipsoid zone (EZ) and external limiting membrane (ELM) between groups assessed independently by 2 masked graders at an external masked image reading center.

Results

A total of 150 participants completed the 12-month follow-up visit. A total of 145 patients (72 PPV and 73 PnR) had gradable spectral-domain optical coherence tomography at 12 months. Analysis of the central 3-mm (foveal) scans found that 24% (n = 17 of 72) vs 7% (n = 5 of 73) displayed EZ discontinuity (difference, 17%; odds ratio [OR], 4.204; 95% CI, 1.458-12.116; P = .005) and 20% (n = 14 of 71) vs 6% (n = 4 of 73) displayed ELM discontinuity (difference, 14%; OR, 4.237; 95% CI, 1.321-13.587; P = .01) in the PPV and PnR groups, respectively. Analysis of the 6-mm (foveal and nonfoveal) scans revealed that EZ and ELM discontinuity was greater in the PPV vs PnR groups (EZ, 32% [n = 23 of 72] vs 11% [n = 8 of 73]; difference, 21%; OR, 3.814; 95% CI, 1.573-9.249; P = .002; ELM, 32% [n = 23 of 71] vs 18% [n = 13 of 73]; difference, 14%; OR, 2.211; 95% CI, 1.015-4.819; P = .04).

Conclusions and Relevance

Discontinuity of the EZ and ELM was more common at 12 months postoperatively following PPV vs PnR for RRD repair. The findings of this post hoc analysis suggest that less discontinuity of the EZ and ELM may provide an anatomic basis for the previously reported superior functional outcomes with PnR, although the analysis does not prove a cause-and-effect relationship.

Trial Registration

ClinicalTrials.gov Identifier: NCT01639209.

Airway Management in Surgical Patients With Obstructive Sleep Apnea

Obstructive sleep apnea (OSA) is the most common sleep-related breathing disorder, and the difficult airway is perhaps the anesthesiologists' quintessential concern. OSA and the difficult airway share certain similar anatomical, morphological, and physiological features. Individual studies and systematic reviews of retrospective, case-control, and large database studies have shown a likely association between patients with OSA and the difficult airway; OSA patients have a 3- to 4-fold higher risk of difficult intubation, difficult mask ventilation, or a combination of both. The presence of OSA should initiate proactive perioperative management in anticipation of a difficult airway. Prudent intraoperative management comprises the use of regional anesthesia where possible and considering an awake intubation technique where there is the presence of notable difficult airway predictors and risk of rapid desaturation following induction of general anesthesia. Familiarity with difficult airway algorithms, cautious extubation, and appropriate postoperative monitoring of patients with OSA are necessary to mitigate perioperative risks.

Imaging Biomarkers and Their Impact on Therapeutic Decision-Making in the Management of Neovascular Age-Related Macular Degeneration

These recommendations, produced by a group of Canadian retina experts, have been developed to assist both retina specialists and general ophthalmologists in the management of vision-threatening neovascular age-related macular degeneration (nAMD). The recommendations are based on published evidence as well as collective experience and expertise in routine clinical practice. We provide an update on practice principles for optimal patient care, focusing on identified imaging biomarkers, in particular retinal fluid, as well as current and emerging therapeutic approaches. Algorithms for delivering high-quality care and improving long-term patient outcomes are provided, with an emphasis on timely and appropriate treatment to preserve and maintain vision. In the context of nAMD, increasing macular fluid or leakage on fluorescein angiography (FA) may indicate disease activity regardless of its location. Early elimination of intraretinal fluid (IRF) is of particular relevance as it is a prognostic indicator of worse visual outcomes. Robust referral pathways for second opinion and peer-to-peer consultations must be in place for cases not responding to intravitreal anti-vascular endothelial growth factor (anti-VEGF) therapy.

MANAGEMENT OF RETINAL PIGMENT EPITHELIUM TEAR DURING ANTI-VASCULAR ENDOTHELIAL GROWTH FACTOR THERAPY

PURPOSE

This article aims to review current evidence on the development, diagnosis, and management of retinal pigment epithelium (RPE) tear during anti-vascular endothelial growth factor (VEGF) therapy.

METHODS

Literature searches were performed using MEDLINE/PubMed databases (cut-off date: August 2019).

RESULTS

Three key recommendations were made based on existing literature and clinical experience: 1) Multimodal imaging with color fundus photography, optical coherence tomography, near-infrared reflectance imaging, fundus autofluorescence imaging, optical coherence tomography-angiography, and/or fluorescein angiography are recommended to diagnose RPE tear and assess risk factors. Retinal pigment epithelium tears can be graded by size and foveal involvement. 2) Patients at high risk of developing RPE tear should be monitored after each anti-VEGF injection. If risk factors worsen, it is not yet definitively known whether anti-VEGF administration should be more frequent, or alternatively stopped in such patients. Prospective research into high-risk characteristics is needed. 3) After RPE tear develops, anti-VEGF treatment should be continued in patients with active disease (as indicated by presence of intraretinal or subretinal fluid), although cessation of therapy should be considered in eyes with multilobular tears.

CONCLUSION

Although evidence to support the assumption that anti-VEGF treatment contributes to development of RPE tear is not definitive, some data suggest this link.

Difficult Airway Management in Adult COVID-19 Patients: Statement by the Society of Airway Management

The COVID-19 disease, caused by Coronavirus SARS-CoV-2, often results in severe hypoxemia requiring airway management. Because SARS CoV-2 virus is spread via respiratory droplets, bag-mask ventilation, intubation, and extubation may place health care workers (HCW) at risk. While existing recommendations address airway management in patients with COVID-19, no guidance exists specifically for difficult airway management. Some strategies normally recommended for difficult airway management may not be ideal in the setting of COVID-19 infection. To address this issue the Society for Airway Management (SAM) created a task force to review existing literature and current Practice Guidelines for management of the difficult airway by the American Society of Anesthesiologists Task Force on Management of the Difficult Airway. SAM task force created recommendations for management of known or suspected difficult airway in the setting of known or suspected COVID-19 infection. The goal of the task force was to optimize successful airway management while minimizing exposure risk. Each member conducted a literature review on specific clinical practice section utilizing standard search engines (PubMed, Ovid, Google Scholar). Existing recommendations and evidence for difficult airway management in COVID-19 context were developed. Each specific recommendation was discussed among task force members and modified until unanimously approved by all task force members. Elements of AGREE Reporting Checklist for dissemination of clinical practice guidelines were utilized to develop this statement. Airway management in the COVID-19 patient increases HCW exposure risk. and difficult airway management often takes longer, may involve multiple procedures with aerosolization potential, strict adherence to personal protective equipment (PPE) protocols is mandatory to reduce risk to providers. When patient's airway risk assessment suggests awake tracheal intubation is an appropriate choice of technique, procedures that may cause increased aerosolization of secretions should be avoided. Optimal preoxygenation before induction with tight seal facemask may be performed to reduce risk of hypoxemia. Unless the patient is experiencing oxygen desaturation, positive pressure bag-mask ventilation after induction may be avoided to reduce aerosolization. For optimal intubating conditions, patients should be anesthetized with full muscle relaxation. Videolaryngoscopy is recommended as first-line strategy for airway management. If emergent invasive airway access is indicated, we recommend a surgical technique such as scalpel-bougie-tube, rather than an aerosolizing generating procedure, such as transtracheal jet ventilation. This statement represents recommendations by SAM task force for the difficult airway management of adults with COVID-19 with the goal to optimize successful airway management while minimizing the risk of clinician exposure.

Anti-VEGF intravitreal injections in the era of COVID-19: responding to different levels of epidemic pressure

Purpose

Following the first wave of the COVID-19 pandemic in early 2020, the easing of strict measures to reduce its spread has led to a resurgence of cases in many countries at both the national and local level. This article addresses how guidance for ophthalmologists on managing patients with retinal disease receiving intravitreal injections of anti-vascular endothelial growth factor (VEGF) during the pandemic should be adapted to the local epidemic pressure, with more or less stringent measures implemented according to the ebb and flow of the pandemic.

Methods

The Vision Academy’s membership of international retinal disease experts analyzed guidance for anti-VEGF intravitreal injections during the COVID-19 pandemic and graded the recommendations according to three levels of increasing epidemic pressure. The revised recommendations were discussed, refined, and voted on by the 14-member Vision Academy Steering Committee for consensus.

Results

Protocols to minimize the exposure of patients and healthcare staff to COVID-19, including use of personal protective equipment, physical distancing, and hygiene measures, should be routinely implemented and intensified according to local infection rates and pressure on the hospital/clinic or healthcare system. In areas with many COVID-19-positive clusters, additional measures including pre-screening of patients, postponement of non-urgent appointments, and simplification of complex intravitreal anti-VEGF regimens should be considered. Treatment prioritization for those at greatest risk of irreversible vision loss should be implemented in areas where COVID-19 cases are increasing exponentially and healthcare resources are strained.

Conclusion

Consistency in monitoring of local infection rates and adjustment of clinical practice accordingly will be required as we move forward through the COVID-19 era. Ophthalmologists must continue to carefully weigh the risk–benefits to minimize the exposure of patients and healthcare staff to COVID-19, ensure that patients receive sight-saving treatment, and avoid the potential long-term impact of prolonged treatment postponement.

Vision-Related Functioning in Patients Undergoing Pneumatic Retinopexy vs Vitrectomy for Primary Rhegmatogenous Retinal Detachment: A Post Hoc Exploratory Analysis of the PIVOT Randomized Clinical Trial

Importance

Although rhegmatogenous retinal detachment (RRD) repair techniques have high anatomical reattachment rates, there may be differences in various aspects of postoperative vision-related quality of life (VRQoL).

Objective

To explore the differences in various aspects of VRQoL between pneumatic retinopexy (PnR) and pars plana vitrectomy (PPV) following RRD repair.

Design, Setting, and Participants

Post hoc exploratory analysis of the the Pneumatic Retinopexy vs Vitrectomy for the Management of Primary Rhegmatogenous Retinal Detachment Outcomes randomized clinical trial conducted between August 2012 and May 2017 at St Michael's Hospital, Toronto, Ontario, Canada. Patients with RRD with a single break or multiple breaks within 1 clock hour of detached retina in the superior 8 clock hours of the retina with any number, location, and size of retinal breaks or lattice degeneration in attached retina.

Main Outcomes and Measures

Differences in the 25-Item National Eye Institute Visual Function Questionnaire 12 subscale scores between the PnR and PPV groups at 6 months following RRD repair.

Results

A total of 160 patients were included in this analysis, with 81 patients (92%) and 79 patients (90%) in the PnR and PPV groups, respectively. The PnR group consisted of 32% women with a mean (SD) age of 60.9 (9.3) years, while the PPV group consisted of 38% women with a mean (SD) age of 60.3 (7.6) years. For the 152 patients with 6-month follow-up (75 patients in PnR [85%] and 77 patients in PPV [88%]), there was evidence for an association of PnR with superior vision-related functioning compared with PPV for several subscales. There were no differences between groups at 1 year. After adjusting for age, sex, baseline macular status, visual acuity in the nonstudy eye, and lens status, patients who underwent PnR had higher scores for distance activities (mean [SD] PnR, 88.7 [13.4]; PPV, 82.8 [17.1]; adjusted difference, 6.5; 95% CI, 1.6-11.4; P = .01), mental health (mean [SD] PnR, 84.3 [17.4]; PPV, 78.7 [21.1]; adjusted difference, 6.7; 95% CI, 0.4-13; P = .04), dependency (mean [SD] PnR, 96.1 [10.1]; PPV, 91.1 [18.6]; adjusted difference, 5.7; 95% CI, 0.6-10.8; P = .03), and peripheral vision (mean [SD] PnR, 91.6 [16.2]; PPV, 81.2 [24.4]; adjusted difference, 10.8; 95% CI, 4.3-17.4; P = .001) at 6 months.

Conclusions and Relevance

These findings demonstrate that patients undergoing PnR for RRD report higher mental health scores and superior vision-related functioning scores in several subscales of the 25-Item National Eye Institute Visual Function Questionnaire during the first 6 months postoperatively compared with PPV.

Trial Registration

ClinicalTrials.gov Identifier: NCT01639209.

Retinal Displacement Following Pneumatic Retinopexy vs Pars Plana Vitrectomy for Rhegmatogenous Retinal Detachment

Importance

Retinal displacement following rhegmatogenous retinal detachment repair may have consequences for visual function. It is important to know whether surgical technique is associated with risk of displacement.

Objective

To compare retinal displacement following rhegmatogenous retinal detachment repair with pneumatic retinopexy (PR) vs pars plana vitrectomy (PPV).

Interventions or Exposures

Fundus autofluorescence images were assessed by graders masked to surgical technique.

Design, Setting, and Participants

A multicenter retrospective consecutive case series in Canada and the UK. A total of 238 patients (238 eyes) with rhegmatogenous retinal detachments treated with PR or PPV who underwent fundus autofluorescence imaging from November 11, 2017, to March 22, 2019, were included.

Main Outcomes and Measures

Proportion of patients with retinal displacement detected by retinal vessel printings on fundus autofluorescence imaging in PR vs PPV.

Results

Of the 238 patients included in the study, 144 were men (60.5%) and 94 were women (39.5%); mean (SD) age was 62.0 (11.0) years. Of the 238 eyes included in this study, 114 underwent PR (47.9%) and 124 underwent PPV (52.1%) as the final procedure to achieve reattachment. Median time from surgical procedure to fundus autofluorescence imaging was 3 months (interquartile range, 1-5 months). Baseline characteristics in both groups were similar. The proportion of eyes with retinal vessel printing on fundus autofluorescence was 7.0% for PR (8 of 114) and 44.4% for PPV (55 of 124) (37.4% difference; 95% CI, 27.4%-47.3%; P < .001). Analysis based on the initial procedure found that 42.4% (42 of 99) of the eyes in the PPV group vs 15.1% (21 of 139) of the eyes in the PR group (including 13 PR failures with subsequent PPV) had displacement (27.3% difference; 95% CI, 15.9%-38.7%; P < .001). Among eyes with displacement in the macula, the mean (SD) displacement was 0.137 (0.086) mm (n = 6) for PR vs 0.297 (0.283) mm (n = 52) for PPV (0.160-mm difference; 95% CI, 0.057-0.263 mm; P = .006). Mean postoperative logMAR visual acuity was 0.31 (0.32) (n = 134) (Snellen equivalent 20/40) in eyes that initially underwent PR and 0.56 (0.42) (n = 84) (Snellen equivalent 20/72) in eyes that had PPV (-0.25 difference; 95% CI, -0.14 to -0.35; P < .001). Among eyes with displacement, mean postoperative logMAR visual acuity was 0.42 (0.42) (n = 20) (Snellen equivalent 20/52) in those that initially underwent PR and 0.66 (0.47) (n = 33) (Snellen equivalent 20/91) in those that initially underwent PPV (-0.24 difference; 95% CI, -0.48 to 0.01; P = .07).

Conclusions and Relevance

These findings suggest that retinal displacement occurs more frequently and is more severe with PPV vs PR when considering the initial and final procedure used to achieve retinal reattachment. Recognizing the importance of anatomic integrity by assessing retinal displacement following reattachment may lead to refinements in vitreoretinal surgery techniques.

Comparing the tracheostomy dislodgement and complication rate of non-sutured neck tie to skin sutured neck tie fixation

INTRODUCTION

Tracheostomy management is a routine aspect of care in the critical care setting. While there are multiple complications that can arise in the post-operative setting after creation of a tracheostomy, dislodgement of a tracheostomy tube is associated with high mortality requiring rapid intervention. It is therefore important to prevent the occurrence with proper securement of the tracheostomy. In this study, we look at two methods commonly used to secure tracheostomy tubes: suturing of the lateral flanges to the skin with the use of cloth neck ties versus cloth neck ties alone.

METHODS

This is a retrospective study with data collected from 1355 consecutive tracheostomy cases at a single institution. Our institution serves the County of San Bernardino, California as a level II trauma center. Patient selection occurred between 2004 and 2018, with distribution of patients to skin-sutured with neck tie tracheostomies (ST) and non-sutured neck tied only tracheostomies (NST) groups occurring by date of tracheostomy surgery. Our study investigates the dislodgement rate of percutaneous tracheostomies secured by either of these two methods. Due to a greater morbidity of tracheostomy dislodgement before a mature fistula tract is formed, we were specifically interested in the dislodgement rate within 7 days.

RESULTS

In total, 328 cases of NST and 1027 cases of ST were collected. Overall, there was no statistically significant difference regarding the dislodgement and accidental decannulation rate between NST and ST (2.32% vs 4.46% for NST and ST, respectively, p = 0.1476). There was also no statistically significant difference regarding rates of dislodgement and accidental decannulation within 7 days between NST and ST (1.54% vs 1.11% for NST and ST, respectively, p = 0.5608).

DISCUSSION

It takes 5-7 days for a tracheostomy tract to mature, and therefore most dislodgement occurs perioperatively within the first week after placement. Dislodgement of the tracheostomy tube can lead to devastating complications for those patients. To our knowledge, there has been no study investigating dislodgement in the early post-operative period in relation to tracheostomy securement method.

CONCLUSION

Due to the emergent nature of tracheostomy dislodgement and loss of airway, prevention of this complication is critical. Our investigation found no statistically significant difference in the rate of early tracheostomy dislodgement in the skin sutured with neck tie and non-sutured neck tie only groups. This study contributes further data to the available literature regarding tracheostomy securement methods and dislodgement rate, specifically within the early post-operative period.

LEVEL OF EVIDENCE

2b.

Canadian Airway Focus Group updated consensus-based recommendations for management of the difficult airway: part 1. Difficult airway management encountered in an unconscious patient

PURPOSE

Since the last Canadian Airway Focus Group (CAFG) guidelines were published in 2013, the literature on airway management has expanded substantially. The CAFG therefore re-convened to examine this literature and update practice recommendations. This first of two articles addresses difficulty encountered with airway management in an unconscious patient.

SOURCE

Canadian Airway Focus Group members, including anesthesia, emergency medicine, and critical care physicians, were assigned topics to search. Searches were run in the Medline, EMBASE, Cochrane Central Register of Controlled Trials, and CINAHL databases. Results were presented to the group and discussed during video conferences every two weeks from April 2018 to July 2020. These CAFG recommendations are based on the best available published evidence. Where high-quality evidence was lacking, statements are based on group consensus.

FINDINGS AND KEY RECOMMENDATIONS

Most studies comparing video laryngoscopy (VL) with direct laryngoscopy indicate a higher first attempt and overall success rate with VL, and lower complication rates. Thus, resources allowing, the CAFG now recommends use of VL with appropriately selected blade type to facilitate all tracheal intubations. If a first attempt at tracheal intubation or supraglottic airway (SGA) placement is unsuccessful, further attempts can be made as long as patient ventilation and oxygenation is maintained. Nevertheless, total attempts should be limited (to three or fewer) before declaring failure and pausing to consider "exit strategy" options. For failed intubation, exit strategy options in the still-oxygenated patient include awakening (if feasible), temporizing with an SGA, a single further attempt at tracheal intubation using a different technique, or front-of-neck airway access (FONA). Failure of tracheal intubation, face-mask ventilation, and SGA ventilation together with current or imminent hypoxemia defines a "cannot ventilate, cannot oxygenate" emergency. Neuromuscular blockade should be confirmed or established, and a single final attempt at face-mask ventilation, SGA placement, or tracheal intubation with hyper-angulated blade VL can be made, if it had not already been attempted. If ventilation remains impossible, emergency FONA should occur without delay using a scalpel-bougie-tube technique (in the adult patient). The CAFG recommends all institutions designate an individual as "airway lead" to help institute difficult airway protocols, ensure adequate training and equipment, and help with airway-related quality reviews.

Lessons Learned From Two Survivors of Greater Than 90% TBSA Full-Thickness Burn Injuries Using NovoSorb Biodegradable Temporizing Matrix™ and Autologous Skin Cell Suspension, RECELL™: A Case Series

Since autologous split-thickness skin grafts are scarce and lab skin growth requires a significant amount of time, there are limited available treatment approaches for patients with full-thickness burns greater than 90% TBSA. Additionally, to achieve the primary goal of skin coverage and resuscitation, there must exist a balance between fluid loss and metabolic derangement. Allografts and xenografts have traditionally been used early in the process to achieve these goals. Currently, novel approaches to treatment consider the additional use of synthetic dermal substitutes and autologous skin cell suspension to improve outcomes. This case series describes the treatment course of patients with greater than 90% TBSA full-thickness burn injuries using a staged, multifaceted approach of using NovoSorb Biodegradable Temporizing Matrix™ as the primary dermal substitute in conjunction with a RECELL™ Autologous Cell Suspensions Device applied with autograft and allograft to achieve improved resuscitation, limiting fluid loss, and finally skin coverage. Allograft and NovoSorb Biodegradable Temporizing Matrix™ were used early to cover excised burns, resulting in improved metabolic control by limiting the systemic inflammatory response syndrome and fluid loss. Both patients survived using this approach.