Plasma pro-atrial natriuretic peptide to estimate fluid balance during open and robot-assisted esophagectomy:a prospective observational study

Abstract Background It remains debated how much fluid should be administered during surgery. The atrial natriuretic peptide precursor proANP is released by atrial distension and deviations in plasma proANP are reported associated with perioperative fluid balance. We hypothesized that plasma proANP would decrease when the central blood volume is compromised during the abdominal part of robot-assisted hybrid (RE) esophagectomy and that a positive fluid balance would be required to maintain plasma proANP. Methods Patients undergoing RE ( n \u2009=\u200925) or open (OE; n \u2009=\u200925) esophagectomy for gastroesophageal cancer were included consecutively in this prospective observational study. Plasma proANP was determined repetitively during esophagectomy to allow for distinction between the abdominal and thoracic part of the procedure. The RE group was 15\ub0 head up tilted during the abdominal procedure. Results The blood loss was 250 (150\u2013375) (RE) and 600\ua0ml (390\u2013855) (OE) ( p \u2009=\u20090.01), but the two groups of patients were provided with a similar positive fluid balance: 1705 (1390\u20131983) vs. 1528\ua0ml (1316\u20131834) ( p \u2009=\u20090.4). However, plasma proANP decreased by 21% ( p \u2009<\u20090.01) during the abdominal part of RE carried out during moderate head-up tilt, but only by 11% ( p \u2009=\u20090.01) during OE where the patients were supine. Plasma proANP and fluid balance were correlated in the RE-group ( r \u2009=\u20090.5 (0.073\u20130.840), p \u2009=\u20090.02) and tended to correlate in the OE group ( r \u2009=\u20090.4 (\u22120.045\u20130.833), p \u2009=\u20090.08). Conclusion The results support that plasma proANP decreases when the central blood volume is compromised and suggest that an about 2200\ua0ml surplus administration of crystalloid is required to maintain plasma proANP during esophagectomy. Trial registration Clinicaltrials.gov ( NCT02077673 ). Registered retrospectively February 12 th 2014

Plasma pro-atrial natriuretic peptide to estimate fluid balance during open and robot-assisted esophagectomy:a prospective observational study

BACKGROUND: It remains debated how much fluid should be administered during surgery. The atrial natriuretic peptide precursor proANP is released by atrial distension and deviations in plasma proANP are reported associated with perioperative fluid balance. We hypothesized that plasma proANP would decrease when the central blood volume is compromised during the abdominal part of robot-assisted hybrid (RE) esophagectomy and that a positive fluid balance would be required to maintain plasma proANP. METHODS: Patients undergoing RE (n = 25) or open (OE; n = 25) esophagectomy for gastroesophageal cancer were included consecutively in this prospective observational study. Plasma proANP was determined repetitively during esophagectomy to allow for distinction between the abdominal and thoracic part of the procedure. The RE group was 15° head up tilted during the abdominal procedure. RESULTS: The blood loss was 250 (150–375) (RE) and 600 ml (390–855) (OE) (p = 0.01), but the two groups of patients were provided with a similar positive fluid balance: 1705 (1390–1983) vs. 1528 ml (1316–1834) (p = 0.4). However, plasma proANP decreased by 21% (p < 0.01) during the abdominal part of RE carried out during moderate head-up tilt, but only by 11% (p = 0.01) during OE where the patients were supine. Plasma proANP and fluid balance were correlated in the RE-group (r = 0.5 (0.073–0.840), p = 0.02) and tended to correlate in the OE group (r = 0.4 (−0.045–0.833), p = 0.08). CONCLUSION: The results support that plasma proANP decreases when the central blood volume is compromised and suggest that an about 2200 ml surplus administration of crystalloid is required to maintain plasma proANP during esophagectomy. TRIAL REGISTRATION: Clinicaltrials.gov (NCT02077673). Registered retrospectively February 12(th) 2014

Thoracic epidural analgesia reduces gastric microcirculation in the pig

BACKGROUND: Thoracic epidural analgesia (TEA) is used for pain relief during and after abdominal surgery, but the effect of TEA on the splanchnic microcirculation remains debated. We evaluated whether TEA affects splanchnic microcirculation in the pig. METHODS: Splanchnic microcirculation was assessed in nine pigs prior to and 15 and 30 min after induction of TEA. Regional blood flow was assessed by neutron activated microspheres and changes in microcirculation by laser speckle contrast imaging (LSCI). RESULTS: As assessed by LSCI 15 min following TEA, gastric arteriolar flow decreased by 22 % at the antrum (p = 0.020) and by 19 % at the corpus (p = 0.029) of the stomach. In parallel, the microcirculation decreased by 19 % at the antrum (p = 0.015) and by 20 % at the corpus (p = 0.028). Reduced arteriolar flow and microcirculation at the antrum was confirmed by a reduction in microsphere assessed regional blood flow 30 min following induction of TEA (p = 0.048). These manifestations took place along with a drop in systolic blood pressure (p = 0.030), but with no significant change in mean arterial pressure, cardiac output, or heart rate. CONCLUSION: The results indicate that TEA may have an adverse effect on gastric arteriolar blood flow and microcirculation. LSCI is a non-touch technique and displays changes in blood flow in real-time and may be important for further evaluation of the concern regarding the effect of thoracic epidural anesthesia on gastric microcirculation in humans. TRIAL REGISTRATIONS: Not applicable, non-human study

Defining medical simulators for simulation-based education in EUS:Theoretical approach and a narrative review

Choosing the right simulator for tasks in simulation-based education in medicine will affect the trainees’ skills. However, there is a shortage in the vocabularies used for describing medical simulators and the contextual usage of simulators. We propose methods for approaching the task of choosing and defining the simulators needed, regardless of it being an acquisition or development process. It is advocated that efforts are made in defining the simulator's requirements before making any choice in regards to development processes. Multiple advantages are attained by keeping the simulator simple, both educational and development wise. Issues on validating simulators are discussed and highlighted as actions where interprofessional communication is likely to fail. The following conventional terms in medical education are problematic in regard to establishing a clear communication: Virtual reality, fidelity, validation, and simulation. The text is finalized in a short discussion on applying the methods in an EUS/endobronchial ultrasound (EBUS) context. The work is the authors’ interpretation of an invitation having the title “Development of EUS and EBUS training models and simulators.