Brent T. Boettcher

Operating room clinicians' ratings of workload: a vignette simulation study.

Objectives Increased clinician workload is associated with medical errors and patient harm. The Quality and Workload Assessment Tool (QWAT) measures anticipated (pre-case) and perceived (post-case) clinical workload during actual surgical procedures using ratings of individual and team case difficulty from every operating room (OR) team member. The purpose of this study was to examine the QWAT ratings of OR clinicians who were not present in the OR but who read vignettes compiled from actual case documentation to assess interrater reliability and agreement with ratings made by clinicians involved in the actual cases. Methods Thirty-six OR clinicians (13 anesthesia providers, 11 surgeons, and 12 nurses) used the QWAT to rate 6 cases varying from easy to moderately difficult based on actual ratings made by clinicians involved with the cases. Cases were presented and rated in random order. Before rating anticipated individual and team difficulty, the raters read prepared clinical vignettes containing case synopses and much of the same written case information that was available to the actual clinicians before the onset of each case. Then, before rating perceived individual and team difficulty, they read part 2 of the vignette consisting of detailed role-specific intraoperative data regarding the anesthetic and surgical course, unusual events, and other relevant contextual factors. Results Surgeons had higher interrater reliability on the QWAT than did OR nurses or anesthesia providers. For the anticipated individual and team workload ratings, there were no statistically significant differences between the actual ratings and the ratings obtained from the vignettes. There were differences for the 3 provider types in perceived individual workload for the median difficulty cases and in the perceived team workload for the median and more difficult cases. Conclusions The case difficulty items on the QWAT seem to be sufficiently reliable and valid to be used in other studies of anticipated and perceived clinical workload of surgeons. Perhaps because of the limitations of the clinical documentation shown to anesthesia providers and OR nurses in the current vignette study, more evidence needs to be gathered to demonstrate the criterion-related validity of the QWAT difficulty items for assessing the workload of nonsurgeon OR clinicians.

Hydroxocobalamin for Vasoplegic Syndrome in Liver Transplantation: Restoration of Blood Pressure Without Vasospasm.

Systemic vasoplegia is common in patients undergoing liver transplantation. In this report, we present a case in which treatment with conventional vasopressors caused peripheral arterial spasm, rendering arterial blood pressure monitoring impossible. Administration of methylene blue resolved the vasospasm; however, concern for toxic dose requirements limited its use. Hydroxocobalamin administration resolved the vasospasm and increased blood pressure without the potential adverse effects seen with methylene blue. This case represents the first report of hydroxocobalamin use in liver transplantation and may represent a new option for the treatment of vasoplegia and the potential vasospasm that may result from traditional vasopressors.

Moderate Aortic Valvular Insufficiency Invalidates Vortex Formation Time as an Index of Left Ventricular Filling Efficiency in Patients With Severe Degenerative Calcific Aortic Stenosis Undergoing Aortic Valve Replacement

OBJECTIVE Transmitral blood flow produces a vortex ring (quantified using vortex formation time [VFT]) that enhances the efficiency of left ventricular (LV) filling. VFT is attenuated in LV hypertrophy resulting from aortic valve stenosis (AS) versus normal LV geometry. Many patients with AS also have aortic insufficiency (AI). The authors tested the hypothesis that moderate AI falsely elevates VFT by partially inhibiting mitral leaflet opening in patients with AS. DESIGN Observational study. SETTING Veterans Affairs medical center. PARTICIPANTS Patients with AS in the presence or absence of moderate AI (n = 8 per group) undergoing aortic valve replacement (AVR) were studied after institutional review board approval. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS Under general anesthesia, peak early LV filling (E) and atrial systole (A) blood flow velocities and their corresponding velocity-time integrals were obtained using pulse-wave Doppler transesophageal echocardiography (TEE) to determine E/A and atrial filling fraction (beta). Mitral valve diameter (D) was calculated as the average of major and minor axis lengths obtained in the midesophageal bicommissural (transcommissural anterior-lateral-posterior medial) and LV long-axis (anterior-posterior) TEE imaging planes, respectively. VFT was calculated as 4·(1-beta)·SV/πD(3), where SV = stroke volume measured using thermodilution. Hemodynamics, diastolic function, and VFT were determined during steady-state conditions before cardiopulmonary bypass. The severity of AS (mean and peak pressure gradients, peak transvalvular jet velocity, aortic valve area) and diastolic function (E/A, beta) were similar between groups. Moderate centrally directed AI was present in 8 patients with AS (ratio of regurgitant jet width to LV outflow tract diameter of 36±6%). Pulse pressure and mean pulmonary artery pressure were elevated in patients with versus without AI, but no other differences in hemodynamics were observed. Mitral valve minor and major axis lengths, diameter, and area were reduced in the presence versus the absence of AI. VFT was increased significantly (5.7±1.7 v 3.2±0.6; p = 0.00108) in patients with AS and AI compared with AS alone. CONCLUSION Moderate AI falsely elevates VFT in patients with severe AS undergoing AVR by partially inhibiting mitral valve opening. VFT may be an unreliable index of LV filling efficiency with competitive diastolic flow into the LV.

Advanced Age Attenuates Left Ventricular Filling Efficiency Quantified Using Vortex Formation Time: A Study of Octogenarians With Normal Left Ventricular Systolic Function Undergoing Coronary Artery Surgery

OBJECTIVE Blood flow across the mitral valve during early left ventricular (LV) filling produces a 3-dimensional rotational fluid body, known as a vortex ring, that enhances LV filling efficiency. Diastolic dysfunction is common in elderly patients, but the influence of advanced age on vortex formation is unknown. The authors tested the hypothesis that advanced age is associated with a reduction in LV filling efficiency quantified using vortex formation time (VFT) in octogenarians undergoing coronary artery bypass graft (CABG) surgery. DESIGN Observational study. SETTING Veterans Affairs medical center. PARTICIPANTS After institutional review board approval, octogenarians (n = 7; 82 ± 2 year [mean ± standard deviation]; ejection fraction 56% ± 7%) without valve disease or atrial arrhythmias undergoing CABG were compared with a younger cohort (n = 7; 55 ± 6 year; ejection fraction 57% ± 7%) who were undergoing coronary revascularization. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS All patients were monitored using radial and pulmonary arterial catheters and transesophageal echocardiography. Peak early LV filling (E) and atrial systole (A) blood flow velocities and their corresponding velocity-time integrals were obtained using pulse-wave Doppler echocardiography to determine E/A, atrial filling fraction (β), and E wave deceleration time. Pulse-wave Doppler also was used to measure pulmonary venous blood flow during systole and diastole. Mitral valve diameter (D) was calculated as the average of major and minor axis lengths obtained in the midesophageal LV bicommissural and long-axis transesophageal echocardiography imaging planes, respectively. VFT was calculated as 4 × (1 - β) × SV/(πD3), where SV is the stroke volume measured using thermodilution. Systemic and pulmonary hemodynamics, LV diastolic function, and VFT were determined during steady-state conditions 30 minutes before cardiopulmonary bypass. A delayed relaxation pattern of LV filling (E/A 0.81 ± 0.16 v 1.29 ± 0.19, p = 0.00015; β 0.44 ± 0.05 v 0.35 ± 0.03, p = 0.0008; E wave deceleration time 294 ± 58 v 166 ± 28 ms, p < 0.0001; ratio of peak pulmonary venous systolic and diastolic blood flow velocity 1.42 ± 0.23 v 1.14 ± 0.20, p = 0.0255) was observed in octogenarians compared with younger patients. Mitral valve diameter was similar between groups (2.7 ± 0.2 and 2.6 ± 0.2 cm, respectively, in octogenarians v younger patients, p = 0.299). VFT was reduced in octogenarians compared with younger patients (3.0 ± 0.9 v 4.5 ± 1.2; p = 0.0171). An inverse correlation between age and VFT was shown using linear regression analysis (VFT = -0.0627 × age + 8.24; r2 = 0.408; p = 0.0139). CONCLUSION The results indicate that LV filling efficiency quantified using VFT is reduced in octogenarians compared with younger patients undergoing coronary artery bypass grafting.

An Unexpected Finding During Repair of an Ascending Aortic Aneurysm

as: Boettcher BT, et al. (2017), http://dx.doi.org/10.1053/j Thoracic computed tomography revealed a 6.6-cm ascending aortic aneurysm. The remainder of the history and physical examination was noncontributory. Transthoracic echocardiogram revealed normal left ventricular systolic and diastolic function, normal right ventricular size and function, no significant valvular lesions, and the ascending aortic aneurysm. Coronary angiography revealed a right dominant system with no obstructive coronary stenoses. The patient was taken to the operating room for aortic aneurysm repair. After anesthetic

Hydroxocobalamin With or Without Methylene Blue May Improve Fluid Balance in Critically Ill Patients With Vasoplegic Syndrome After Cardiac Surgery: A Report of Two Cases

Fluid resuscitation is a cornerstone of the treatment of vasodilation associated with vasoplegic syndrome after cardiopulmonary bypass. Excessive nitric oxide production contributes to capillary leak and creates the need for ongoing volume resuscitation. In this report, the authors describe two patients with vasoplegic syndrome after cardiac surgery in which treatment with hydroxocobalamin in the presence or absence of methylene blue reduced volume resuscitation requirements and restored catecholamine responsiveness. The current case series describes the possible efficacy of hydroxocobalamin for reversing positive fluid balance associated with catecholamine-refractory vasoplegic syndrome in cardiac surgery patients.

A Rare Complication of Metastatic Osteosarcoma

Fig 2. Modified midesophageal 4-chamber transesophageal echocardiography image showing pericardial mass (arrow). A33-YEAR-OLD, 80-kg, 184-cm man, with a 5-year history of poorly differentiated osteosarcoma of the proximal left femur with pulmonary involvement, presented to the authors’ institution for evaluation of progressive exertional dyspnea. The patient’s lower extremity malignancy originally was treated with radical surgical resection. He subsequently underwent bilateral thoracotomies for resection of pulmonary metastases concomitant with several courses of radiation therapy and adjuvant and neoadjuvant chemotherapy for palliative treatment of his disease. Thoracic computed tomography performed 3 months before the current admission revealed several new pulmonary metastases. In addition, many of the residual metastases in the patient’s lungs were enlarging despite palliative treatment with nivoloumab and liposomal doxorubicin. A small pericardial effusion also was present. On admission, the patient denied experiencing fever, fatigue, dizziness, syncope, chest pain, palpitations, dyspnea at rest,

Anesthetic management of a parturient with Stiff person syndrome for urgent cesarean delivery

Stiff person syndrome is a rare neurologic disorder with an estimated incidence of 1:1000000. The underlying pathophysiology is truncal and proximal limb muscle stiffness resulting from continuous co-contracture of agonist and antagonist muscle groups concomitant with superimposed episodic muscle spasms. Loss of gamma-aminobutyric acid-mediated inhibition creates chronic excitation manifested by tonic agonist-antagonist muscle contraction. To date, only three case reports referred indirectly to the anesthetic management of parturients with Stiff person syndrome. The authors describe their management of a parturient with Stiff person syndrome who underwent urgent cesarean delivery under epidural anesthesia.

Acute Severe Thrombocytopenia Occurring After Administration of Eptifibatide Postpones Emergent Coronary Artery Surgery.

Introduction Eptifibatide is a platelet glycoprotein IIb/IIIa (GP IIb/IIIa) receptor antagonist that inhibits fibrinogen binding to the activated GP IIb/IIIa site and prevents platelet-platelet interaction and clot formation. GP IIb/IIIa inhibitors improve outcome in patients undergoing percutaneous coronary intervention for acute coronary syndrome. Thrombocytopenia is a complication of GP IIb/IIIa inhibitors, but severe thrombocytopenia is unusual. Most reported cases of severe thrombocytopenia after eptifibatide occurred in patients with acute coronary syndrome. The authors describe a patient who developed acute profound thrombocytopenia after receiving eptifibatide before emergent coronary artery bypass graft surgery. Case Presentation A 67-year-old man with a normal platelet count (220 K/uL) developed atrial fibrillation, left bundle branch block, and respiratory insufficiency consistent with acute coronary syndrome two days after colectomy. He received eptifibatide during cardiac catheterization, where three-vessel coronary artery disease was encountered. Emergent coronary artery surgery was planned, but the platelet count before surgery was 2 K/uL. Eptifibatide was discontinued, surgery was postponed, and acute coronary syndrome was treated with intraaortic balloon counterpulsation. Conclusions The authors describe the second reported case of eptifibatide-induced severe thrombocytopenia associated with cardiac surgery. In this case, discontinuation of eptifibatide and transfusion of apheresis platelets increased the platelet count (137 K/uL) the following day, and the patient subsequently underwent successful coronary artery surgery using cardiopulmonary bypass.