Perioperative non-invasive versus semi-invasive cardiac index monitoring in patients with bariatric surgery - a prospective observational study

• Published in: BMC anesthesiology 2020-08, Vol.20 (1), p.196-196, Article 196
• Main Authors: Lorenzen, Ulf, Pohlmann, Markus, Hansen, Jonathan, Klose, Phil, Gruenewald, Matthias, Renner, Jochen, Elke, Gunnar
• Format: Article
• Language: English
• Subjects: Analysis; Anesthesia; Arterial lines; Bariatric surgery; Bias; Blood pressure; Cardiac output; Cardiac patients; Care and treatment; Catheterization; Catheters; Comorbidity; Diabetes; Echocardiography; Finger-cuff; Gastrointestinal surgery; General anesthesia; Heart; Hemodynamic monitoring; Laparoscopy; Medical research; Non-invasive monitoring; Obesity; Observational studies; Patients; Physiology; Posture; Pressure transducers; Pulmonary arteries; Standard deviation; Stroke; Surgery; Unloading
• ISSN: 1471-2253; 1471-2253
• DOI: 10.1186/s12871-020-01110-x

In morbidly obese patients undergoing laparoscopic bariatric surgery, the combination of obesity-related comorbidities, pneumoperitoneum and extreme posture changes constitutes a high risk of perioperative hemodynamic complications. Thus, an advanced hemodynamic monitoring including continuous cardiac index (CI) assessment is desirable. While invasive catheterization may bear technical difficulties, transesophageal echocardiography is contraindicated due to the surgical procedure. Evidence on the clinical reliability of alternative semi- or non-invasive cardiac monitoring devices is limited. The aim was to compare the non-invasive vascular unloading to a semi-invasive pulse contour analysis reference technique for continuous CI measurements in bariatric surgical patients. This prospective observational study included adult patients scheduled for elective, laparoscopic bariatric surgery after obtained institutional ethics approval and written informed consent. CI measurements were performed using the vascular unloading technique (Nexfin®) and semi-invasive reference method (FloTrac™). At 10 defined measurement time points, the influence of clinically indicated body posture changes, passive leg raising, fluid bolus administration and pneumoperitoneum was evaluated pre- and intraoperatively. Correlation, Bland-Altman and concordance analyses were performed. Sixty patients (mean BMI 49.2 kg/m ) were enrolled into the study and data from 54 patients could be entered in the final analysis. Baseline CI was 3.2 ± 0.9 and 3.3 ± 0.8 l/min/m , respectively. Pooled absolute CI values showed a positive correlation (r  = 0.76, P