J. Kyle Bohman

Anesthesia Care Transitions and Risk of Postoperative Complications.

BACKGROUND:A patient undergoing surgery may receive anesthesia care from several anesthesia providers. The safety of anesthesia care transitions has not been evaluated. Using unconditional and conditional multivariable logistic regression models, we tested whether the number of attending anesthesiologists involved in an operation was associated with postoperative complications. METHODS:In a cohort of patients undergoing elective colorectal surgical in an academic tertiary care center with a stable anesthesia care team model participating in the American College of Surgeons National Surgical Quality Improvement Program, using unconditional and conditional multivariable logistic regression models, we tested adjusted associations between numbers of attending anesthesiologists and occurrence of death or a major complication (acute renal failure, bleeding that required a transfusion of 4 units or more of red blood cells within 72 hours after surgery, cardiac arrest requiring cardiopulmonary resuscitation, coma of 24 hours or longer, myocardial infarction, unplanned intubation, ventilator use for 48 hours or more, pneumonia, stroke, wound disruption, deep or organ-space surgical-site infection, superficial surgical-site infection, sepsis, septic shock, systemic inflammatory response syndrome). RESULTS:We identified 927 patients who underwent elective colectomy of comparable surgical intensity. In all, 71 (7.7%) patients had major nonfatal complications or death. One anesthesiologist provided care for 530 (57%) patients, 2 anesthesiologists for 287 (31%), and 3 or more for 110 (12%). The number of attending anesthesiologists was associated with increased odds of postoperative complication (unadjusted odds ratio [OR] = 1.52, 95% confidence interval [CI] 1.18–1.96, P = 0.0013; adjusted OR = 1.44, 95% CI 1.09–1.91, P = 0.0106). In sensitivity analyses, occurrence of a complication was significantly associated with the number of in-room providers, defined as anesthesia residents and nurse anesthetists (adjusted OR = 1.39, 95% CI 1.01–1.92, P = 0.0446) and for all anesthesia providers (adjusted OR = 1.58, 95%CI 1.20–2.08, P = 0.0012). Findings persisted across multiple, alternative adjustments, sensitivity analyses, and conditional logistic regression with matching on operative duration. CONCLUSIONS:In our study, care by additional attending anesthesiologists and in-room providers was independently associated with an increased odds of postoperative complications. These findings challenge the assumption that anesthesia transitions are care neutral and not contributory to surgical outcomes.

Airway Pepsin Levels in Otherwise Healthy Surgical Patients Receiving General Anesthesia With Endotracheal Intubation

BACKGROUND Airway pepsin has been increasingly used as a potentially sensitive and quantifiable biomarker for gastric-to-pulmonary aspiration, despite lack of validation in normal control subjects. This study attempts to define normal levels of airway pepsin in adults and distinguish between pepsin A (exclusive to stomach) and pepsin C (which can be expressed by pneumocytes). METHODS We performed a prospective study of 51 otherwise healthy adult patients undergoing elective extremity orthopedic surgery at a single tertiary-care academic medical center. Lower airway samples were obtained immediately following endotracheal intubation and just prior to extubation. Total pepsin and pepsin A concentrations were directly measured by an enzymatic activity assay, and pepsin C was subsequently derived. Pepsinogen/pepsin C was confirmed by Western blot analyses. Baseline characteristics were secondarily compared. RESULTS In all, 11 (22%; 95% CI = 9.9%-33%) had detectable airway pepsin concentrations. All 11 positive specimens had pepsin C, without any detectable pepsin A. Pepsinogen/pepsin C was confirmed by Western blot analyses. In a multivariate logistic regression, men were more likely to have airway pepsin (OR, 12.71, P = .029). CONCLUSIONS Enzymatically active pepsin C, but not the gastric-specific pepsin A, is frequently detected in the lower airways of patients who otherwise have no risk for aspiration. This suggests that nonspecific pepsin assays should be used and interpreted with caution as a biomarker of gastropulmonary aspiration, as pepsinogen C potentially expressed from pneumocytes may be detected in airway samples.

Severe Acute Cardiopulmonary Failure Related to Gadobutrol Magnetic Resonance Imaging Contrast Reaction: Successful Resuscitation with Extracorporeal Membrane Oxygenation

Nonanaphylactic noncardiogenic pulmonary edema leading to cardiorespiratory arrest related to the magnetic resonance imaging contrast agent gadobutrol has rarely been reported in the literature. Rarer is the association of hypokalemia with acidosis. We report 2 patients who had severe pulmonary edema associated with the use of gadobutrol contrast in the absence of other inciting agents or events. These cases were unique not only for their rare and severe presentations but also because they exemplified the increasing role of extracorporeal membrane oxygenation in resuscitation. Emergency extracorporeal membrane oxygenation resuscitation can be rapidly initiated and successful in the setting of a well-organized workflow, and it is a viable alternative and helps improve patient outcome in cases refractory to conventional resuscitative measures.

Early prediction of extracorporeal membrane oxygenation eligibility for severe acute respiratory distress syndrome in adults.

PURPOSE Appropriately identifying and triaging patients with newly diagnosed acute respiratory distress syndrome (ARDS) who may progress to severe ARDS is a common clinical challenge without any existing tools for assistance. MATERIALS AND METHODS Using a retrospective cohort, a simple prediction score was developed to improve early identification of ARDS patients who were likely to progress to severe ARDS within 7 days. A broad array of comorbidities and physiologic variables were collected for the 12-hour period starting from intubation for ARDS. Extracorporeal membrane oxygenation (ECMO) eligibility was determined based on published criteria from recent ECMO guidelines and clinical trials. Separate data-driven and expert opinion approaches to prediction score creation were completed. RESULTS The study included 767 patients with moderate or severe ARDS who were admitted to the intensive care unit between January 1, 2005, and December 31, 2010. In the data-driven approach, incorporating the ARDS index (a novel variable incorporating oxygenation index and estimated dead space), aspiration, and change of Pao2/fraction of inspired oxygen ratio into a simple prediction model yielded a c-statistic (area under the receiver operating characteristic curve) of 0.71 in the validation cohort. The expert opinion-based prediction score (including oxygenation index, change of Pao2/fraction of inspired oxygen ratio, obesity, aspiration, and immunocompromised state) yielded a c-statistic of 0.61 in the validation cohort. CONCLUSIONS The data-driven early prediction ECMO eligibility for severe ARDS score uses commonly measured variables of ARDS patients within 12 hours of intubation and could be used to identify those patients who may merit early transfer to an ECMO-capable medical center.

A Pilot Randomized Clinical Trial Assessing the Effect of Cricoid Pressure on Risk of Aspiration.

Patients at risk for microaspiration during elective intubation often receive cricoid pressure in the hopes of mitigating such risk. However, there is scarce evidence to either support or reject this practice. The objective of this investigation was to assess the effect of cricoid pressure on microaspiration and to inform the potential feasibility of conducting a larger, more definitive clinical trial.

Retrospective report of contraindications to extracorporeal membrane oxygenation (ECMO) among adults with acute respiratory distress syndrome (ARDS)

OBJECTIVES To determine the incidence of contraindications to extracorporeal membrane oxygenation (ECMO) among adults with acute respiratory distress syndrome (ARDS) and assess the impact of contraindications on the number of patients receiving ECMO (case volume). BACKGROUND The extent to which contraindications may affect case volumes has not been described. METHODS Retrospective, observational study at an academic tertiary medical center. The records of 730 consecutive patients with ARDS were queried for respiratory ECMO eligibility and ECMO contraindications. RESULTS Of the 730 patients with ARDS, 168 (23.0%) met ECMO inclusion criteria and 515 (70.5%) never met ECMO eligibility due to inadequately severe disease. Among 168 patients who met ECMO inclusion criteria, 1 or more relative contraindications were present in 144 (85.7%) patients. The three most common relative contraindications were immunocompromised state (58.3%), multiorgan dysfunction (29.2%) and contraindication to anticoagulation (16.7%). CONCLUSIONS Application of relative contraindications may greatly affect ECMO case volumes.

Aspiration Following Elective Intubation

We have additional fi ndings regarding our study in CHEST (May 2013) 1 of gastric-to-pulmonary aspiration in adult surgical patients undergoing elective intubation. Th e original study used an enzymatic assay for identifi cation of pepsin A. Since publication, our group has validated an enzyme-linked immunosorbant assay (ELISA) for pepsin A, which we subsequently used to analyze the same airway samples collected in our previous study. 1

Incidence of gastric-to-pulmonary aspiration in patients undergoing elective upper gastrointestinal endoscopy

© 2018 by the AGA Institute 1542-3565/

Histopathologic Findings in Lungs of Patients Treated With Extracorporeal Membrane Oxygenation

36.00 https://doi.org/10.1016/j.cgh.2017.11.024 Before this study, the data regarding the risk of gastric-to-pulmonary aspiration in the upper gastrointestinal (GI) endoscopy population was critically lacking. Because of oropharyngeal manipulation during upper GI endoscopy and concomitant underlying gastrointestinal pathologies, there was concern that this population would have a higher risk of aspiration. Prospective data have shown a high incidence of “high risk” residual gastric material observed during elective upper GI endoscopy (12.2%) despite patient-reported fasting in accordance with the current guidelines. Other investigators have collected prospective data of endoscopic retrograde cholangiography that have shown an incidence of cardiopulmonary complications (but not specifically aspiration) of 10.3% (34% of these were fatal). We performed a focused investigation of the incidence of aspiration in patients undergoing elective upper GI endoscopy.

Gibbons of the world, dream on.

BACKGROUND: The outcome of extracorporeal membrane oxygenation (ECMO) might be influenced by its complications. Only limited information is available regarding the pathologic consequences of ECMO, especially in the era of modern ECMO technology. METHODS: We studied the histopathologic findings in autopsy lungs of patients treated with ECMO compared with those without ECMO. Autopsy files were queried for cases with ECMO. An age‐ and sex‐matched control group comprised of patients who died in the ICU without acute respiratory distress syndrome, pneumonia, or ECMO was compared with patients with ECMO for cardiac reason. Histopathology and medical records were reviewed. RESULTS: Seventy‐six patients treated with ECMO (38 men; median age, 40 years) and 47 control patients (23 men; median age, 45 years) were included. Common histologic pulmonary findings in the ECMO group were pulmonary hemorrhage (63.2%), acute lung injury (60.5%), thromboembolic disease (47.4%), calcifications (28.9%), vascular changes (21.1%), and hemorrhagic infarct (21.1%). Pulmonary hemorrhage was associated with longer ECMO duration (median, 7.0 vs 3.5 months; P = .014), acute lung injury with venovenous ECMO (91.7% vs 54.7%; P = .039) and longer ECMO (6.0 vs 4.0 months; P = .044), and pulmonary calcifications with infants (50.0% vs 22.4%; P = .024). Patients with ECMO for cardiac reasons (n = 60) more frequently showed pulmonary hemorrhage (P < .001), diffuse alveolar damage (P = .044), thromboembolic disease (P = .004), hemorrhagic infarct (P = .002), pulmonary calcifications (P = .002), and vascular changes (P = .001) than patients in the non‐ECMO group. CONCLUSIONS: Some findings are suspected to be associated with the patients underlying disease, whereas others might be related to ECMO. Our results provide a better understanding of ECMO‐related lung disease and might help to prevent it.