Mojca Remskar Konia

Nuclear factor-κB inhibition provides additional protection against ischaemia/reperfusion injury in delayed sevoflurane preconditioning

Background and objective Sevoflurane anaesthetic preconditioning (SPC) has been shown to limit nuclear factor-κB (NF-κB) activation and the production of inflammatory cytokines during myocardial ischaemia/reperfusion (I/R). Similarly, pharmacological inhibition of NF-κB using parthenolide is effective in limiting I/R injury. We, therefore, postulated that the protective effect of delayed SPC would be enhanced by pharmacological NF-κB inhibition during I/R. Methods Hearts from 2-month-old male Fisher 344 rats were exposed to 25 min global ischaemia followed by 60 min reperfusion. Rats were divided into four groups prior to I/R: control group; parthenolide group, treated with the IκB kinase inhibitor parthenolide intraperitoneally 10 min prior to heart isolation; SPC group, treated for 60 min with sevoflurane 48 h prior to heart isolation; and SPC + parthenolide group, treated with SPC for 1 h followed by parthenolide 48 h later. Infarct area, left ventricular function and Ca2+i were measured after I/R. Results Delayed SPC + parthenolide resulted in greater protection than either intervention alone, resulting in a significant reduction in infarct area and left ventricular developed pressure (mmHg; 84 ± 19 compared with 15 ± 14 in control hearts; P = 0.007). Left ventricular end-diastolic pressure also remained close to baseline values (9 ± 2 mmHg, P = 0.02) during I/R, and the increase in Ca2+i seen with I/R was significantly blunted (P = 0.005). Conclusion SPC followed by parthenolide provides a significant protection from I/R injury in this model. As each intervention alone limits NF-κB activation with I/R, these data are consistent with additive effects of these dual modalities in limiting I/R injury due to NF-κB activation.

The association between ASA status and other risk stratification models on postoperative intensive care unit outcomes.

BACKGROUND:There is limited medical literature investigating the association between perioperative risk stratification methods and surgical intensive care unit (SICU) outcomes. Our hypothesis contends that routine assessments such as higher ASA physical status classification, surgical risk as defined by American College of Cardiology/American Heart Association guidelines, and simplified Revised Cardiac Index (SRCI) can reliably be associated with SICU outcomes. METHODS:We performed a chart review of all patients 18 years or older admitted to the SICU between October 1, 2010, and March 1, 2011. We collected demographic and preoperative clinical data: age, sex, ASA physical status class, surgical risk, and SRCI. Outcome data included our primary end point, SICU length of stay, and secondary end points: mechanical ventilation and vasopressor treatment duration, number of acquired organ dysfunctions (NOD), readmission to the intensive care unit (ICU) within 7 days, SICU mortality, and 30-day mortality. Regression analysis and nonparametric tests were used, and P < 0.05 was considered significant. RESULTS:We screened 239 patients and included 220 patients in the study. The patients’ mean age was 58 ± 16 years. There were 32% emergent surgery and 5% readmissions to the SICU within 7 days. The SICU mortality and the 30-day mortality were 3.2%. There was a significant difference between SICU length of stay (2.9 ± 2.1 vs 5.9 ± 7.4, P = 0.007), mechanical ventilation (0.9 ± 2.0 vs 3.4 ± 6.8, P = 0.01), and NOD (0 [0–2] vs 1 [0–5], P < 0.001) based on ASA physical status class (⩽ 2 vs ≥ 3). Outcomes significantly associated with ASA physical status class after adjusting for confounders were: SICU length of stay (incidence rate ratio [IRR] = 1.79, 95% confidence interval [CI], 1.35–2.39, P < 0.001), mechanical ventilation (IRR = 2.57, 95% CI, 1.69–3.92, P < 0.001), vasopressor treatment (IRR = 3.57, 95% CI, 1.84–6. 94, P < 0.001), NOD (IRR = 1.71, 95% CI, 1.46–1.99, P < 0.001), and readmission to ICU (odds ratio = 3.39, 95% CI, 1.04–11.09, P = 0.04). We found significant association between surgery risk and NOD (IRR = 1.56, 95% CI, 1.29–1.89, P < 0.001, and adjusted IRR = 1.31, 95% CI, 1.05–1.64, P = 0.02). SRCI was not significantly associated with SICU outcomes. CONCLUSIONS:Our study revealed that ASA physical status class is associated with increased SICU length of stay, mechanical ventilation, vasopressor treatment duration, NOD, readmission to ICU, and surgery risk is associated with NOD.

Ascending aortic pseudoaneurysm: a late complication of coronary artery bypass.

An 83-yr-old man, with a history of myocardial infarction and coronary artery bypass grafting surgery performed 21 yr ago, presented with increasing midsternal chest pain radiating to his back and shortness of breath. He was diagnosed with a non-ST-elevation myocardial infarction. Cardiac catheterization showed an occluded saphenous vein graft to the first diagonal branch and a mass attached to the ascending aorta with uncertain involvement of the saphenous vein graft. Magnetic resonance imaging (MRI) showed a pseudoaneurysm, measuring 4.6 12.5 cm, which appeared to originate from the saphenous vein graft to the diagonal branch. The pseudoaneurysm had bloodflow into an approximately 5 2.4 cm oblong space that was surrounded by a spherical, heterogeneous, formed hematoma. The pseudoaneurysm extended superiorly to the level of the aortic arch and inferiorly to the level of the diaphragm. It significantly compressed the superior vena cava, right atrium (RA), and right ventricle (RV). Surgery to excise the pseudoaneurysm was planned with right subclavian artery/femoral vein cardiopulmonary bypass and deep hypothermic circulatory arrest. Radial and pulmonary arterial catheters were placed for hemodynamic monitoring; no significant RV pressure increase was noticed (34/4 mm Hg). A thorough intraoperative transesophageal echocardiography (TEE) was performed to look for the characteristics of a pseudoaneurysm that include a thin-walled cavity and expansion during systole and collapse during diastole. The TEE showed a thin-walled cavity that was filled with a nonhomogeneous material and did not expand or collapse with systole and diastole. Color Doppler examination showed what appeared to be bloodflow in the cavity (Video clips 1 and 2; please see video clips available at www.anesthesia-analgesia. org), but this finding did not correlate with the location of bloodflow demonstrated previously by MRI and angiography. The TEE confirmed RA and RV compression with mild tricuspid regurgitation (Figs. 1, 2, and Video clip 1). The aortic valve (AV) appeared normal in both the mid-esophageal (ME) AV short and long axis views. The ascending aorta was also normal from the upper esophageal aortic arch long axis view, ME AV long axis view, ME ascending aortic long axis view, and the ME left ventricular (LV) long axis view. A right anterior thoracotomy approach was used and, after cardiopulmonary bypass was established, the patient’s temperature was decreased to 20°C. The pseudoaneurysm was excised and brown-colored fluid with necrotic material was evacuated. During careful inspection, two small holes were identified in the lateral wall of the ascending aorta located 1.5 cm above the aortic valve. The bleeding pressure from the two holes was very low and no communication with the saphenous vein graft was noted. Suture repair of the ascending aorta was made easier by a transient 2-min circulatory arrest. After resection of the pseudoaneurysm, the compression of the RA and RV were significantly relieved (Video clip 2). The descending aorta was then carefully examined by TEE and no additional pathology was found. The patient recovered uneventfully. A pseudoaneurysm, also known as a false aneurysm, is an outpouching of a blood vessel caused by a defect in the two innermost layers (tunica intima and media) with continuity of the outermost layer (tunica adventitia). Alternatively, all three layers are damaged and the bleeding is contained by a blood clot or This article has supplementary material on the Web site: www.anesthesia-analgesia.org.

Simulation-a new educational paradigm?

Simulation is a modern educational tool that has recently gained in the field of medical education. The use of simulation continues to expand, and studies evaluating the effectiveness of simulation-based medical education are ongoing. The history of medical education and adult educational theory are reviewed, and the details of effective simulation techniques are described. Finally, outcomes of simulation-based medical education are summarized.

Simulation-based education for transfusion medicine.

The administration of blood products is frequently determined by physicians without subspecialty training in transfusion medicine (TM). Education in TM is necessary for appropriate utilization of resources and maintaining patient safety. Our institution developed an efficient simulation‐based TM course with the goal of identifying key topics that could be individualized to learners of all levels in various environments while also allowing for practice in an environment where the patient is not placed at risk.

Unrecognized bilateral temporomandibular joint dislocation after general anesthesia with a delay in diagnosis and management: a case report.

IntroductionAnterior bilateral temporomandibular joint dislocation is not an uncommon occurrence and has been reported before. However, its diagnosis can easily be overlooked, especially by clinicians who are unfamiliar with this pathology. Continuous discussion of the pathology is required to prevent delays in diagnosis, which can lead to long-term sequelae for the patient.Case presentationWe present the case of a 66-year-old Somali woman who experienced a bilateral anterior temporomandibular joint dislocation after a general anesthetic for an exploratory laparotomy for excision of a pelvic sarcoma. She first presented in the intensive care unit with preauricular pain and an inability to close her mouth, and was initially misdiagnosed and treated for a muscle spasm. The cause of her misdiagnosis was multifactorial - opioid-related sedation, language and cultural barrier, and unfamiliarity with the pathology. Her diagnosis was proven 18 hours after the completion of surgery with a plain X-ray. A manual closed reduction was performed with minimal sedation by oral surgery.ConclusionWe provided an in-depth discussion of temporomandibular joint dislocation and suggest a simple test that would prevent delayed diagnosis of temporomandibular joint dislocation in any patient undergoing general anesthesia. A normal mandibular excursion should be tested in every patient after surgery in the postoperative care unit, by asking the patient to open and close their mouth during the immediate postoperative recovery period or passively performing the range of motion test.

Asystole following positive pressure insufflation of right pleural cavity: a case report

IntroductionAdverse hemodynamic effects with severe bradycardia have been previously reported during positive pressure insufflation of the right thoracic cavity in humans. To the best of our knowledge, this is the first report of asystole during thoracoscopic surgery with positive pressure insufflation.Case presentationA 63-year-old Caucasian woman developed asystole at the onset of positive pressure insufflation of her right hemithorax during a thoracoscopic single-lung ventilation procedure. Immediate deflation of pleural cavity, intravenous glycopyrrolate and atropine administration returned her heart rhythm to normal sinus rhythm. The surgery proceeded in the absence of positive pressure insufflation without any further complications.ConclusionsWe discuss the proposed mechanisms of hemodynamic instability with positive pressure thoracic insufflation, and anesthetic and insufflation techniques that decrease the likelihood of adverse hemodynamic events.

Identifying variability in mental models within and between disciplines caring for the cardiac surgical patient

BACKGROUND: The cardiac operating room is a complex environment requiring efficient and effective communication between multiple disciplines. The objectives of this study were to identify and rank critical time points during the perioperative care of cardiac surgical patients, and to assess variability in responses, as a correlate of a shared mental model, regarding the importance of these time points between and within disciplines. METHODS: Using Delphi technique methodology, panelists from 3 institutions were tasked with developing a list of critical time points, which were subsequently assigned to pause point (PP) categories. Panelists then rated these PPs on a 100-point visual analog scale. Descriptive statistics were expressed as percentages, medians, and interquartile ranges (IQRs). We defined low response variability between panelists as an IQR ⩽ 20, moderate response variability as an IQR > 20 and ⩽ 40, and high response variability as an IQR > 40. RESULTS: Panelists identified a total of 12 PPs. The PPs identified by the highest number of panelists were (1) before surgical incision, (2) before aortic cannulation, (3) before cardiopulmonary bypass (CPB) initiation, (4) before CPB separation, and (5) at time of transfer of care from operating room (OR) to intensive care unit (ICU) staff. There was low variability among panelists’ ratings of the PP “before surgical incision,” moderate response variability for the PPs “before separation from CPB,” “before transfer from OR table to bed,” and “at time of transfer of care from OR to ICU staff,” and high response variability for the remaining 8 PPs. In addition, the perceived importance of each of these PPs varies between disciplines and between institutions. CONCLUSIONS: Cardiac surgical providers recognize distinct critical time points during cardiac surgery. However, there is a high degree of variability within and between disciplines as to the importance of these times, suggesting an absence of a shared mental model among disciplines caring for cardiac surgical patients during the perioperative period. A lack of a shared mental model could be one of the factors contributing to preventable errors in cardiac operating rooms.

Diastolic regurgitation through a bi-leaflet mechanical valve in the mitral position

A 64-yr-old man presented for aortic valve replacement due to worsening aortic insufficiency (AI) associated with left ventricular (LV) dilation. He had a history of mitral valve replacement with a bi-leaflet mechanical St. Jude’s valve 15 yr before this surgery. Preoperative transthoracic echocardiography showed 3–4 AI and mitral regurgitation (MR) estimated to be 3 . The ejection fraction was assessed as 60%. Cardiac catheterization demonstrated no significant coronary artery disease, AI 3–4 , MR 1 and an ejection fraction of 40%. Aortic valve replacement with possible aortic root replacement was planned. An intraoperative precardiopulmonary bypass transesophageal echocardiogram was requested by the surgeon to examine the mechanical mitral valve for signs of significant regurgitation requiring surgical treatment. During intraoperative transesophageal echocardiogram, the aortic valve was evaluated in the midesophageal aortic valve short-axis view and midesophageal aortic valve long-axis view. The right and noncoronary cusp of the aortic valve were thin and stretched and were prolapsing into the LV outflow tract. Central edges of the leaflets were thickened and mildly retracted with focal areas of calcification. The AI jet was eccentric, directed towards and under the mitral valve leaflets. It was estimated as 3–4 based on over 6 mm width of the vena contracta, AI height/LV outflow tract diameter ratio of 70% and holosystolic retrograde flow in the descending aorta. The bi-leaflet prosthetic mitral valve leaflets could be well visualized in the midesophageal four-chamber view and appeared to be moving well and symmetrically. Color Doppler examination of the mitral valve in different midesophageal views demonstrated MR estimated as 1–2 . On careful examination, we were able to distinguish systolic regurgitant jets consistent with expected mechanical valve backflow (washing jets) (Fig. 1, Video clip 1; please see video clip available at www.anesthesia-analgesia.org) and a separate diastolic mechanical valve regurgitant jet. The diastolic jet appeared to be related to the eccentric jet of AI (Fig. 2, Video clip 1). No paravalvular leaks were noted. Aortic root replacement using a 27 mm St. Jude valve graft conduit with mechanical valve was performed. Transesophageal echocardiography after aortic root and valve replacement demonstrated good function of the mechanical valve in the aortic position with backflow jets. The bi-leaflet mechanical valve in the mitral position was re-examined after surgery and showed only backflow systolic jets (Video clip 2). The diastolic jet, observed before aortic valve replacement, had completely disappeared.

Not all unprofessional behaviors are equal: The creation of a checklist of bad behaviors

Abstract Introduction: Professionalism is a key component of medical education and training. However, there are few tools to aid educators in diagnosing unprofessional behavior at an early stage. The purpose of this study was to employ policy capturing methodology to develop two empirically validated checklists for identifying professionalism issues in early-career physicians. Method: In a series of workshops, a professionalism competency model containing 74 positive and 70 negative professionalism behaviors was developed and validated. Subsequently, 23 subject matter experts indicated their level of concern if each negative behavior occurred 1, 2, 3, 4, or 5 or more times during a six-month period. These ratings were used to create a “brief” and “extended” professionalism checklist for monitoring physician misconduct. Results: This study confirmed the subjective impression that some unprofessional behaviors are more egregious than others. Fourteen negative behaviors (e.g. displaying obvious signs of substance abuse) were judged to be concerning if they occurred only once, whereas many others (e.g. arriving late for conferences) were judged to be concerning only when they occurred repeatedly. Discussion: Medical educators can use the professionalism checklists developed in this study to aid in the early identification and subsequent remediation of unprofessional behavior in medical students and residents.