Search

Crystalloids are commonly used as priming solutions during cardiopulmonary bypass (CPB). Consequently, hemodilution is a regular occurrence at the start of a CPB. This study describes the time-course variations of hemodynamic parameters, plasma volume (PV) and fluid exchange following crystalloid hemodilution at start of normothermic CPB. Forty-five anesthetized piglets were given 60-min normothermic CPB. Ringer's solution was used as priming solution and maintenance fluid. Fluid input/losses, PV, colloid osmotic pressures (plasma/interstitium), hematocrit, and s-proteins were measured, and fluid extravasation rates (FER) and intravascular protein-masses calculated. Start of CPB resulted in a 25–30% hemodilution. To keep the fluid level of the CPB-reservoir constant after start of bypass, fluid addition [2.08 ± 0.36 (mean ± SEM) ml kg−1 min−1] was necessary during the first 5 min. Thereafter the fluid needs to be leveled off [0.17 ± 0.03 ml kg−1 min−1 (10–60 min), P < 0.001]. Fluid extravasation rate increased immediately following hemodilution from a baseline value of 0.08 ± 0.01 to 1.75 ± 0.34 ml kg−1 min−1 with a delayed decrease compared to fluid additions, to reach a ‘steady-state’ level of 0.22 ± 0.03 ml kg−1 min−1 after 30 min ( P < 0.001). Differences in time-course variations between fluid added and fluid extravasated were accompanied by changes in PV and mean arterial pressure. The colloid osmotic gradient decreased about 50% throughout the study and could partly explain the increased FER. Acute crystalloid hemodilution contributes to fluid overload during normothermic CPB. The resulting increase in fluid extravasation is, however, moderate, short-lived and levels off to baseline values within 30 min. [ABSTRACT FROM AUTHOR]

Background: According to current guidelines, initial burn resuscitation should be performed with fluids alone. The aims of the study were to review the frequency of use of vasoactive and/or inotropic drugs in initial burn resuscitation, and assess the benefits and harms of adding such drugs to fluids., Methods: A systematic literature search was conducted in PubMed, Embase, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, UpToDate, and SveMed+ through 3 December 2021. The search included studies on critically ill burn patients receiving vasoactive and/or inotropic drugs in addition to fluids within 48 h after burn injury., Results: The literature search identified 1058 unique publications that were screened for inclusion. After assessing 115 publications in full text, only two retrospective cohort studies were included. One study found that 16 out of 52 (31%) patients received vasopressor(s). Factors associated with vasopressor use were increasing age, burn depth, and % total body surface area (TBSA) burnt. Another study observed that 20 out of 111 (18%) patients received vasopressor(s). Vasopressor use was associated with increasing age, Baux score, and %TBSA burnt in addition to more frequent dialysis treatment and increased mortality. Study quality assessed by the Newcastle-Ottawa quality assessment scale was considered good in one study, but uncertain due to limited description of methods in the other., Conclusion: This systematic review revealed that there is a lack of evidence regarding the benefits and harms of using vasoactive and/or inotropic drugs in addition to fluids during early resuscitation of patients with major burns., (© 2022 The Authors. Acta Anaesthesiologica Scandinavica published by John Wiley & Sons Ltd on behalf of Acta Anaesthesiologica Scandinavica Foundation.)