Left ventricular regional function and relaxation: effects of inotropic stimulation.

The effects of increasing doses of two inotropes, isoproterenol and calcium chloride (CaCl2), on left ventricular regional myocardial function and isovolumic relaxation were studied in six anesthetized sheep. After baseline data, CaCl2 was given as intravenous boluses to yield doses of 10 mg/kg, 20 mg/kg, 40 mg/kg, 80 mg/kg, and 160 mg/kg. After a second series of baseline data were obtained, constant infusions of isoproterenol were begun with doses of 0.025 micrograms/kg/min, 0.05 micrograms/kg/min, 0.1 micrograms/kg/min, 0.2 micrograms/kg/min, and 0.4 micrograms/kg/min. During each stage of the protocol with both inotropes, data were recorded during acute constriction of the descending thoracic aorta. Left ventricular relaxation was assessed by analysis of peak negative left ventricular (LV) dP/dt and the time constant of isovolumic left ventricular relaxation (Trelax). Regional myocardial function showed little change in either apical or basal segments until high doses of the inotropes. Peak negative LV dP/dt significantly changed from baseline (775 +/- 60 mmHg/s) with 0.2 micrograms/kg/min (1780 +/- 400 mmHg/s, P < 0.05 v baseline) and 0.4 micrograms/kg/min (2,220 +/- 380 mmHg/s, P < 0.05 v baseline) of isoproterenol, and was unchanged by CaCl2. Trelax was significantly decreased by all doses of isoproterenol, whereas only one dose of CaCl2 decreased Trelax. Trelax was increased with afterloading and this effect was altered by isoproterenol. It is concluded that isoproterenol hastens, whereas CaCl2 does not alter, left ventricular relaxation. This may reflect beta-adrenergic modulation of calcium fluxes during isovolumic relaxation

Frailty In Patients Undergoing Vascular Surgery: A Narrative Review Of Current Evidence

Nikoletta Rahel Czobor,1,2 Jean-Jacques Lehot,3,4 Eniko Holndonner-Kirst,1 Phillip J Tully,5 Janos Gal,6 Andrea Szekely6,7 1Medical Centre of Hungarian Defense Forces, Department of Anesthesiology and Intensive Care, Budapest, Hungary; 2Semmelweis University, School of Doctoral Studies, Budapest, Hungary; 3Claude-Bernard University, Health Services and Performance Research Lab (EA 7425 HESPER), Lyon, France; 4Hôpital Neurologique Pierre Wertheimer, Department of Neuroanesthesia and Intensive Care, Hospices Civils de Lyon, Lyon, France; 5University of Adelaide, Freemasons Foundation Centre for Men’s Health, Adelaide, Australia; 6Semmelweis University, Department of Anesthesiology and Intensive Care, Budapest, Hungary; 7Semmelweis University, Heart and Vascular Center of Városmajor, Budapest, HungaryCorrespondence: Andrea SzekelyDepartment of Anaesthesiology and Intensive Therapy, Semmelweis University, Üllői út 78, Budapest 1082, HungaryTel +36206632243Email [email protected]: Frailty is presumably associated with an elevated risk of postoperative mortality and adverse outcome in vascular surgery patients. The aim of our review was to identify possible methods for risk assessment and prehabilitation in order to improve recovery and postoperative outcome. The literature search was performed via PubMed, Embase, OvidSP, and the Cochrane Library. We collected papers published in peer-reviewed journals between 2001 and 2018. The selection criterion was the relationship between vascular surgery, frailty and postoperative outcome or mortality. A total number of 52 publications were included. Frailty increases the risk of non-home discharge independently of presence or absence of postoperative complications and it is related to a higher 30-day mortality and major morbidity. The modified Frailty Index showed significant association with elevated risk for post-interventional stroke, myocardial infarction, prolonged in-hospital stays and higher readmission rates. When adjusted for comorbidity and surgery type, frailty seems to impact medium-term survival (within 2 years). Preoperative physical exercising, avoidance of hypalbuminemia, psychological and cognitive training, maintenance of muscle strength, adequate perioperative nutrition, and management of smoking behaviours are leading to a reduced length of stay and a decreased incidence of readmission rate, thus improving the effectiveness of early rehabilitation. Pre-frailty is a dynamically changing state of the patient, capable of deteriorating or improving over time. With goal-directed preoperative interventions, the decline can be prevented.Keywords: preoperative risk assessment, postoperative outcome, patient management, prehabilitatio

Usefulness of procalcitonin for diagnosis of infection in cardiac surgical patients.

OBJECTIVE: To determine the value of procalcitonin (PCT) as a marker of postoperative infection after cardiac surgery. DESIGN: A prospective single institution three phase study. SETTING: University cardiac surgical intensive care unit (31 beds). PATIENTS: Phase 1: To determine the normal perioperative kinetics of PCT, 20 consecutive patients undergoing elective cardiac surgery with cardiopulmonary bypass were included. Phase 2: To determine whether PCT may be useful for diagnosis of postoperative infection, 97 consecutive patients with suspected infection were included. Phase 3: To determine the ability of PCT to differentiate patients with septic shock from those with cardiogenic shock, 26 patients with postoperative circulatory failure were compared. MEASUREMENTS AND MAIN RESULTS: Phase 1: Serum samples were drawn for PCT determination after induction of anesthesia (baseline), at the end of surgery, and daily until postoperative day (POD) 8. Baseline serum PCT concentration was 0.17 +/- 0.08 ng/mL (mean +/- SD). Serum PCT increased after cardiac surgery with a peak on POD 1 (1.08 +/- 1.36). Serum PCT returned to normal range on POD 3 and remained stable thereafter. Phase 2: In patients with suspected infection, serum PCT was measured at the same time of C-reactive protein (CRP) and bacteriologic samples. Among the 97 included patients, 54 were infected with pneumonia (n = 17), bacteremia (n = 16), mediastinitis (n = 9), or septic shock (n = 12). In the 43 remaining patients, infection was excluded by microbiological examinations. In noninfected patients, serum PCT concentration was 0.41 +/- 0.36 ng/mL (range, 0.08-1.67 ng/mL). Serum PCT concentration was markedly higher in patients with septic shock (96.98 +/- 119.61 ng/mL). Moderate increase in serum PCT concentration occurred during pneumonia (4.85 +/-3.31 ng/mL) and bacteremia (3.57 +/- 2.98 ng/mL). Serum PCT concentration remained low during mediastinitis (0.80 +/- 0.58 ng/mL). Five patients with mediastinitis, two patients with bacteremia, and one patient with pneumonia had serum PCT concentrations of <1 ng/mL. These eight patients were administered antibiotics previously and serum PCT was measured during a therapeutic antibiotic window. For prediction of infection by PCT, the best cutoff value was 1 ng/mL, with sensitivity 85%, specificity 95%, positive predictive value 96%, and negative predictive value 84%. Serum CRP was high in all patients without intergroup difference. For prediction of infection by CRP, a value of 50 mg/L was sensitive (84%) but poorly specific (40%). Comparing the area under the receiver operating characteristic curves, PCT was better than CRP for diagnosis of postoperative sepsis (0.82 for PCT vs. 0.68 for CRP). Phase 3: Serum PCT concentration was significantly higher in patients with septic shock than in those with cardiogenic shock (96.98 +/- 119.61 ng/mL vs. 11.30 +/- 12.3 ng/mL). For discrimination between septic and cardiogenic shock, the best cutoff value was 10 ng/mL, with sensitivity of 100% and specificity of 62%. CONCLUSION: Cardiac surgery with cardiopulmonary bypass influences serum PCT concentration with a peak on POD 1. In the presence of fever, PCT is a reliable marker for diagnosis of infection after cardiac surgery, except in patients who previously received antibiotics. PCT was more relevant than CRP for diagnosis of postoperative infection. During a postoperative circulatory failure, a serum PCT concentration >10 ng/mL is highly indicative of a septic shock