Fluid management in patients undergoing neurosurgery

Fluid management is an important component of perioperative care for patients undergoing neurosurgery. The primary goal of fluid management in neurosurgery is the maintenance of normovolemia and prevention of serum osmolarity reduction. To maintain normovolemia, it is important to administer fluids in appropriate amounts following appropriate methods, and to prevent a decrease in serum osmolarity, the choice of fluid is essential. There is considerable debate about the choice and optimal amounts of fluids administered in the perioperative period. However, there is little high-quality clinical research on fluid therapy for patients undergoing neurosurgery. This review will discuss the choice and optimal amounts of fluids in neurosurgical patients based on the literature, recent issues, and perioperative fluid management practices.

Perioperative fluid management-Goal Directed Therapy (GDT)

Perioperative goal-directed hemodynamic therapy is a protocolized treatment strategy aimed at optimization of global cardiovascular dynamics, including oxygen delivery to tissues and organ perfusion pressure. This is achieved by titrating fluids, vasopressors, and inotropes to predefined physiological target values of hemodynamic variables. Its scope is to reduce complications (acute kidney disease, pulmonary oedema, respiratory distress syndrome, wound infections), decrease major abdominal and systemic postoperative complications, length of stay and postoperative morbidity and mortality mainly in high-risk patients undergoing major surgery. Identifying patients in whom perioperative goal-directed hemodynamic therapy can actually improve postoperative outcomes is crucial. This is a review focusing on all the aspects of GDFT compared to standard fluid therapy during surgery.

Perioperative liberal versus restrictive fluid strategies and postoperative outcomes: a systematic review and metanalysis on randomised-controlled trials in major abdominal elective surgery

Background Postoperative complications impact on early and long-term patients’ outcome. Appropriate perioperative fluid management is pivotal in this context; however, the most effective perioperative fluid management is still unclear. The enhanced recovery after surgery pathways recommend a perioperative zero-balance, whereas recent findings suggest a more liberal approach could be beneficial. We conducted this trial to address the impact of restrictive vs. liberal fluid approaches on overall postoperative complications and mortality. Methods Systematic review and meta-analysis, including randomised controlled trials (RCTs). We performed a systematic literature search using MEDLINE (via Ovid), EMBASE (via Ovid) and the Cochrane Controlled Clinical trials register databases, published from 1 January 2000 to 31 December 2019. We included RCTs enrolling adult patients undergoing elective abdominal surgery and comparing the use of restrictive/liberal approaches enrolling at least 15 patients in each subgroup. Studies involving cardiac, non-elective surgery, paediatric or obstetric surgeries were excluded. Results After full-text examination, the metanalysis finally included 18 studies and 5567 patients randomised to restrictive (2786 patients; 50.0%) or liberal approaches (2780 patients; 50.0%). We found no difference in the occurrence of severe postoperative complications between restrictive and liberal subgroups [risk difference (95% CI) = 0.009 (− 0.02; 0.04); p value = 0.62; I2 (95% CI) = 38.6% (0–66.9%)]. This result was confirmed also in the subgroup of five studies having a low overall risk of bias. The liberal approach was associated with lower overall renal major events, as compared to the restrictive [risk difference (95% CI) = 0.06 (0.02–0.09); p value = 0.001]. We found no difference in either early (p value = 0.33) or late (p value = 0.22) postoperative mortality between restrictive and liberal subgroups Conclusions In major abdominal elective surgery perioperative, the choice between liberal or restrictive approach did not affect overall major postoperative complications or mortality. In a subgroup analysis, a liberal as compared to a restrictive perioperative fluid policy was associated with lower overall complication renal major events, as compared to the restrictive. Trial Registration CRD42020218059; Registration: February 2020, https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=218059.

Consistency Analysis of Intraoperative Blood Loss Assessment Between Surgeons and Anesthesiologists

Objective: To explore the consistency between intraoperative blood loss recorded by surgeons, anesthesiologists and standard blood loss. Methods: The clinical data of 200 patients who underwent posterior lumbar interbody fusion (PLIF) from January 2019 to December 2020 in the Department of Spine Surgery of a Grade III Level A hospital were selected, including 109 males, aged 34-84 years, with an average of 56.40 ± 11.21 years, and 91 females, aged 27-78 years, with an average of 57.48 ± 11.40 years. The preoperative Hb, HCT, APTT, Pt, INR, intraoperative blood, and fluid infusion of patients were recorded. The standard blood loss of the patients was calculated by the formula and compared with the intraoperative blood loss recorded by the surgeons and the anesthesiologists separately for analysis. Results: 1. When the standard blood loss was less than 400ml, there was no statistical difference between the intraoperative blood loss recorded by surgeons and the standard blood loss (P > 0.05), which is considered to be consistent. 2. When the standard blood loss was between 400ml-800ml, the intraoperative blood loss recorded by surgeons and anesthesiologists was less than the standard blood loss,there was statistical difference between the intraoperative blood loss and the standard blood loss (P < 0.05), but the intraoperative blood loss recorded by surgeons was more accurate than that recorded by anesthesiologists; 3. When the standard blood loss was more than 800ml, the intraoperative blood loss recorded by surgeons and anesthesiologists was less than the standard blood loss,There was no consistency between the intraoperative blood loss recorded by anesthesiologists and the standard blood loss (P < 0.05), but the intraoperative blood loss recorded by anesthesiologists was more accurate than that recorded by surgeons. Conclusion: 1. There are differences between surgeons and anesthesiologists in recording intraoperative blood loss. 2. The accurate recording of intraoperative blood loss needs to be done jointly by surgeons and anesthesiologists, especially when the blood loss is more than 400ml, which is conducive to perioperative fluid management.

Association between perioperative fluid administration and postoperative outcomes: a 20-year systematic review and a meta-analysis of randomized goal-directed trials in major visceral/noncardiac surgery

Background Appropriate perioperative fluid management is of pivotal importance to reduce postoperative complications, which impact on early and long-term patient outcome. The so-called perioperative goal-directed therapy (GDT) approach aims at customizing perioperative fluid management on the individual patients’ hemodynamic response. Whether or not the overall amount of perioperative volume infused in the context of GDT could influence postoperative surgical outcomes is unclear. Methods We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) comparing the efficacy of GDT approach between study population and control group in reducing postoperative complications and perioperative mortality, using MEDLINE, EMBASE and the Cochrane Controlled Clinical trials register. The enrolled studies were grouped considering the amount infused intraoperatively and during the first 24 h after the admission in the critical care unit (perioperative fluid). Results The metanalysis included 21 RCTs enrolling 2729 patients with a median amount of perioperative fluid infusion of 4500 ml. In the studies reporting an overall amount below or above this threshold, the differences in postoperative complications were not statically significant between controls and GDT subgroup [43.4% vs. 34.2%, p value = 0.23 and 54.8% vs. 39.8%; p value = 0.09, respectively]. Overall, GDT reduced the overall rate of postoperative complications, as compared to controls [pooled risk difference (95% CI) = − 0.10 (− 0.14, − 0.07); Chi2 = 30.97; p value < 0.0001], but not to a reduction of perioperative mortality [pooled risk difference (95%CI) = − 0.016 (− 0.0334; 0.0014); p value = 0.07]. Considering the rate of organ-related postoperative events, GDT did not reduce neither renal (p value = 0.52) nor cardiovascular (p value = 0.86) or pulmonary (p value = 0.14) or neurological (p value = 0.44) or infective (p value = 0.12) complications. Conclusions Irrespectively to the amount of perioperative fluid administered, GDT strategy reduces postoperative complications, but not perioperative mortality. Trial Registration CRD42020168866; Registration: February 2020 https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=168866