Trajectory of plasma syndecan-1 and heparan sulphate during major surgery: A retrospective observational study.

BACKGROUND: Surgical trauma-induced inflammation during major surgery may disrupt endothelial integrity and affect plasma concentrations of glycocalyx constituents, such as syndecan-1 and heparan sulphate. To date, no studies have focused on their perioperative temporal changes. METHODS: As part of a trial, we obtained plasma and urine specimens sampled during the perioperative period in 72 patients undergoing major abdominal surgery. The plasma concentration of syndecan-1 and heparan sulphate was measured on five occasions, from baseline to the second postoperative day. Plasma and urinary creatinine and urinary syndecan-1 concentrations were measured before surgery and on the first postoperative morning. RESULTS: We observed three different temporal patterns of plasma syndecan-1 concentration. Group 1 'low' (64% of patients) showed only minor changes from baseline despite a median heparan sulphate increase of 67% (p < .005). Group 2 'increase' (21% of patients) showed a marked increase in median plasma syndecan-1 from 27 µg/L to 118 µg/L during the first postoperative day (p < .001) with a substantial (+670%; p < .005) increase in median plasma heparan sulphate from 279 to 2196 µg/L. Group 3 'high' (14% of patients) showed a constant elevation of plasma syndecan-1 to >100 µg/L, but low heparan sulphate levels. The plasma C-reactive protein concentration did not differ across the three groups and 90% of colon surgeries occurred in Group 1. Treatment with dexamethasone was similar across the three groups. Surgical blood loss, duration of surgery and liver resection were greatest in Group 2. CONCLUSION: Changes in syndecan-1 and heparan sulphate after surgery appear to show three different patterns, with the greatest increases in those patients with greater blood loss, more liver surgery and longer operations. These observations suggest that increases in syndecan-1 and heparan sulphate reflect the degree of surgical injury.

A Randomized, Multicenter, Open-Label, Blinded End Point, Phase 2, Feasibility, Efficacy, and Safety Trial of Preoperative Microvascular Protection in Patients Undergoing Major Abdominal Surgery.

BACKGROUND: The endothelial glycocalyx, a carbohydrate-rich layer coating all endothelial surfaces, plays a fundamental role in the function of microcirculation. The primary aim of this study was to evaluate the feasibility of using dexamethasone and albumin to protect the endothelial glycocalyx in patients undergoing abdominal surgery. Secondary and exploratory outcomes included efficacy and safety. METHODS: We conducted a multicenter, open-label, blinded end point, phase 2, randomized trial. Patients undergoing colorectal, pancreas, or liver surgery were recruited and randomized to receive either intravenous dexamethasone (16 mg) and 20% albumin (100 mL) at induction of anesthesia, then 200 mL of 20% albumin with each subsequent 1000 mL of crystalloid administered (dexamethasone and albumin [Dex-Alb] group), or crystalloid fluid only with no dexamethasone (control group). Feasibility end points included patient recruitment and retention, consent rate, and successful study drug administration. The primary efficacy end point was the measurement of plasma syndecan-1 level on postoperative day (POD) 1, and secondary end points were heparan sulfate levels and inflammatory markers measured at 4 perioperative timepoints. Safety end points included errors in administration of the intervention, hyperglycemia, occurrence of postoperative complications, and patient retention. RESULTS: Seventy-two patients were randomized. All feasibility end points were achievable. There were no statistically significant differences observed in median (interquartile range) syndecan-1 levels on POD 1 (39 ng·mL-1 [20-97] in the Dex-Alb group versus 41 ng·mL-1 [19-84] in the control group; difference in medians -2.1, 95% confidence interval [CI], -13 to 8.6; P = .69). The Dex-Alb group had lower POD 1 heparan sulfate levels (319 ng·mL-1 [161-717] in the Dex-Alb group versus 1422 [670-2430] ng·mL-1 in the control group; difference in medians -1085, 95% CI, -1779 to -391) and C-reactive protein (CRP) levels on POD 1 (48 [29-77] mg·L-1 in the Dex-Alb group versus 85 mg·L-1 [49-133] in the control group; difference in medians -48, 95% CI, -75 to -21). Fewer patients had one or more postoperative complication in the Dex-Alb group than in the control group (6 [17%] vs 18 patients [50%]; odds ratio = 0.2, 95% CI, 0.06-0.6). CONCLUSIONS: Intravenous dexamethasone and albumin administration was feasible but did not reduce syndecan-1 on POD 1 in patients undergoing abdominal surgery. Given the clinically important CIs observed between the groups for heparan sulfate, CRP, and postoperative complications, a larger trial assessing the associations between dexamethasone and albumin administration and these outcomes is warranted.

The association of acute hypercarbia and plasma potassium concentration during laparoscopic surgery: a retrospective observational study.

BACKGROUND: It is uncertain whether increases in PaCO2 during surgery lead to an increase in plasma potassium concentration and, if so, by how much. Hyperkalaemia may result in cardiac arrhythmias, muscle weakness or paralysis. The key objectives were to determine whether increases in PaCO2 during laparoscopic surgery induce increases in plasma potassium concentrations and, if so, to determine the magnitude of such changes. METHODS: A retrospective observational study of adult patients undergoing laparoscopic abdominal surgery was perfomed. The independent association between increases in PaCO2 and changes in plasma potassium concentration was assessed by performing arterial blood gases within 15 min of induction of anaesthesia and within 15 min of completion of surgery. RESULTS: 289 patients were studied (mean age of 63.2 years; 176 [60.9%] male, and mean body mass index of 29.3 kg/m2). At the completion of the surgery, PaCO2 had increased by 5.18 mmHg (95% CI 4.27 mmHg to 6.09 mmHg) compared to baseline values (P < 0.001) with an associated increase in potassium concentration of 0.25 mmol/L (95% CI 0.20 mmol/L to 0.31 mmol/L, P < 0.001). On multiple regression analysis, PaCO2 changes significantly predicted immediate changes in plasma potassium concentration and could account for 33.1% of the variance (r2 = 0.331, f(3,259) = 38.915, P < 0.001). For each 10 mmHg increment of PaCO2 the plasma potassium concentration increased by 0.18 mmol/L. CONCLUSION: In patients receiving laparoscopic abdominal surgery, there is an increase in PaCO2 at the end of surgery, which is independently associated with an increase in plasma potassium concentration. However, this effect is small and is mostly influenced by intravenous fluid therapy (Plasma-Lyte 148 solution) and the presence of diabetes. Trial registration Retrospectively registered in the Australian New Zealand Clinical Trials Registry (Trial Number: ACTRN12619000716167).

Acute Kidney Injury and Postoperative Atrial Fibrillation In Patients Undergoing Cardiac Surgery.

OBJECTIVE: To test the hypothesis that acute kidney injury (AKI) in the postoperative period could be an additional risk factor for the development of atrial fibrillation (AF) and to examine the risk factors for postoperative AF in the authors' cohort of patients. DESIGN: A retrospective observational study. SETTING: Large regional cardiothoracic surgical center in the UK. PARTICIPANTS: Patients undergoing elective cardiac surgery at the authors' institution between July 1, 2013, and December 31, 2018. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: A total of 5,588 patients were included in the study. The incidence of postoperative AF was 1,384 (24.8%), and postoperative AKI occurred in 686 patients (12.3%). Postoperative AKI was significantly associated with postoperative AF after adjustment for preoperative variables (adjusted odds ratio = 1.572; 95% confidence interval = 1.295-1.908; p < 0.001). Other factors associated with postoperative AF were increasing age; increasing body mass index; New York Heart Association class ≥III; previous congestive heart failure; and recent myocardial infarction, coronary artery bypass graft with valve surgery, and aortic surgery (all p < 0.05). CONCLUSIONS: This analysis of a large, contemporary cohort of patients identifies postoperative AKI as an associated risk factor for postoperative AF, along with other perioperative variables. Early identification of this patient cohort would allow targeted preventative treatment to reduce the incidence of postoperative AF.

The effect of an intraoperative patient-specific, surgery-specific haemodynamic algorithm in improving textbook outcomes for hepatobiliary-pancreatic surgery: a multicentre retrospective study.

Background: The concept of a "textbook outcome" is emerging as a metric for ideal surgical outcomes. We aimed to evaluate the impact of an advanced haemodynamic monitoring (AHDM) algorithm on achieving a textbook outcome in patients undergoing hepatobiliary-pancreatic surgery. Methods: This retrospective, multicentre observational study was conducted across private and public teaching sectors in Victoria, Australia. We studied patients managed by a patient-specific, surgery-specific haemodynamic algorithm or via usual care. The primary outcome was the effect of using a patient-specific, surgery-specific AHDM algorithm for achieving a textbook outcome, with adjustment using propensity score matching. The textbook outcome criteria were defined according to the International Expert Delphi Consensus on Defining Textbook Outcome in Liver Surgery and Nationwide Analysis of a Novel Quality Measure in Pancreatic Surgery. Results: Of the 780 weighted cases, 477 (61.2%, 95% CI: 57.7%-64.6%) achieved the textbook outcome. Patients in the AHDM group had a higher rate of textbook outcomes [n = 259 (67.8%)] than those in the Usual care group [n = 218 (54.8%); p < 0.001, estimated odds ratio (95% CI) 1.74 (1.30-2.33)]. The AHDM group had a lower rate of surgery-specific complications, severe complications, and a shorter hospital length of stay (LOS) [OR 2.34 (95% CI: 1.30-4.21), 1.79 (95% CI: 1.12-2.85), and 1.83 (95% CI: 1.35-2.46), respectively]. There was no significant difference between the groups for hospital readmission and mortality. Conclusions: AHDM use was associated with improved outcomes, supporting its integration in hepatobiliary-pancreatic surgery. Prospective trials are warranted to further evaluate the impact of this AHDM algorithm on achieving a textbook impact on long-term outcomes.

Serum Creatinine Levels and Nephrocheck® Values With and Without Correction for Urine Dilution-A Multicenter Observational Study.

BACKGROUND: The Nephrocheck® test is a single-use cartridge designed to measure the concentrations of two novel cell-cycle arrest biomarkers of acute kidney injury, namely tissue inhibitor of metalloproteinase 2 (TIMP-2) and insulin-like growth factor binding protein 7 (IGFBP7). Correlations of serum creatine values and TIMP-2 and IGFBP7 with and without correction for urine dilution have not been previously undertaken in patients undergoing major abdominal surgery. We hypothesized that the Nephrocheck® values would be significantly different with and without correction for urine dilution in patients with elevated creatinine values post major abdominal surgery. METHODS: We performed a post hoc analysis of serum and urine specimens sampled preoperatively and postoperatively in 72 patients undergoing major abdominal surgery. Thirty samples were measured from patients with the greatest decrease and the greatest increase in postoperative serum creatinine values. Urine was analyzed with the Nephrocheck to predict the risk of acute kidney injury (AKIRisk™). We then examined the relationship between serum creatinine and the urinary excretion of TIMP-2 and IGFBP7 as measured by the Nephrocheck test. The AKIRisk between the groups with and without correction for urine dilution was assessed. RESULTS: The median perioperative change in serum creatinine in the two groups was -19% and +57%, respectively. The uncorrected median baseline AKIRisk decreased from 0.70 (25th-75th percentiles, 0.09-1.98) to 0.35 (0.19-0.57) (mg/L)2 in the first group and rose from 0.57 (0.22-1.53) to 0.85 (0.67-2.20) (mg/L)2 in the second group. However, when corrected for the squared urine dilution, the AKIRisk™ in patients with postoperative increases in serum creatinine was not indicative of kidney injury; the corrected AKIRisk was 8.0 (3.2-11.7) µg2/mmol2 before surgery vs.6.9 (5.3-11.0) µg2/mmol2 after the surgery (P = 0.69). CONCLUSION: In the setting of major abdominal surgery, after correction of TIMP-2 and IGFBP7 for urine dilution, the Nephrocheck AKIRisk scores were significantly different from the uncorrected values. These finding imply that the AKIRisk index is a function of urine flow in addition to an increased release of the biomarkers.

Audit of emergency department assessment and management of patients presenting with community-acquired needle stick injuries.

OBJECTIVES: To describe characteristics and management of people with community acquired needle stick injuries (CANSI) attending urban emergency departments; and suggest a guideline to improve assessment, management, and documentation. METHODS: A retrospective analysis of cases with CANSI attending emergency departments in two tertiary hospitals between 2001 and 2005 using medical record review with follow up phone and written survey. RESULTS: Thirty-nine cases met the criteria for CANSI. Persons younger than 30 years sustained 48.72% of all injuries. Source serology was available for only five cases (12.82%). Thirty-one of thirty-nine patients (79.49%) were classed as not immune to hepatitis B but only four of these (12.90%) received both hepatitis B vaccination and hepatitis B immunoglobulin. Six patients (15.38%) received HIV prophylaxis; of which two (33.33%) did not receive baseline HIV testing. Of ten patients referred to immunology clinic for follow up only two (20.00%) attended at 6 months. CONCLUSION: We have identified groups that are at high risk of CANSI, including young males, security workers and cleaners. In the majority of cases protection against hepatitis B was inadequately provided, and a substantial proportion had inadequate baseline assessment and documentation. A guideline is suggested that may be used to improve these deficits.

"Talk-Through Walk-Through"-A Simulation Approach Adapted During Preparation for COVID-19.

SUMMARY STATEMENT: Talk-through walk-through is a simulation format that enables the rapid development and improvement of complex systems for patient care. This approach was adapted from task analysis literature and used to develop and test processes for the safe management of COVID-19 patients. Talk-through walk-through is a 2-part process that is paired with a simulated clinical scenario. The talk-through focuses on identifying and solving major process issues and establishing a shared mental model. The walk-through tests these proposed solutions and identifies previously unanticipated system and process challenges. The talk-through walk-through approach enables process development and testing in a single session, making it particularly valuable for patient care systems that involve multiple locations and healthcare disciplines, and where the availability of these disciplines and time are scarce.

Postoperative complications and hospital costs following small bowel resection surgery.

BACKGROUND: Postoperative complications after major gastrointestinal surgery are a major contributor to hospital costs. Thus, reducing postoperative complications is a key target for cost-containment strategies. We aimed to evaluate the relationship between postoperative complications and hospital costs following small bowel resection. METHODS: Postoperative complications were recorded for 284 adult patients undergoing major small bowel resection surgery between January 2013 and June 2018. Complications were defined and graded according to the Clavien-Dindo classification system. In-hospital cost of index admission was calculated using an activity-based costing methodology; it was reported in US dollars at 2019 rates. Regression modeling was used to investigate the relationships among a priori selected perioperative variables, complications, and costs. FINDINGS: The overall complication prevalence was 81.6% (95% CI: 85.7-77.5). Most complications (69%) were minor, but 22.9% of patients developed a severe complication (Clavien-Dindo grades III or IV). The unadjusted median total hospital cost for patients with any complication was 70% higher than patients without complications (median [IQR] USD 19,659.64 [13,545.81-35,407.14] vs. 11,551.88 [8,849.46-15,329.87], P < 0.001). The development of 1, 2, 3, and ≥ 4 complications increased hospital costs by 11%, 41%, 50%, and 195%, respectively. Similarly, more severe complications incurred higher hospital costs (P < 0.001). After adjustments were made (for the Charlson Comorbidity Index, anemia, surgical urgency and technique, intraoperative fluid administration, blood transfusion, and hospital readmissions), a greater number and increased severity of complications were associated with a higher adjusted median hospital cost. Patients who experienced complications had an adjusted additional median cost of USD 4,187.10 (95% CI: 1,264.89-7,109.31, P = 0.005) compared to those without complications. CONCLUSIONS: Postoperative complications are a key target for cost-containment strategies. Our findings demonstrate a high prevalence of postoperative complications following small bowel resection surgery and quantify their associated increase in hospital costs. TRIAL REGISTRATION: Australian Clinical Trials Registration number: 12620000322932.

Potassium levels after liver reperfusion in adult patients undergoing cadaveric liver transplantation: A retrospective cohort study.

BACKGROUND: Hyperkalemia is a common cause of arrhythmias in patients undergoing liver transplantation. We examined the pattern of change of potassium levels during and immediately after reperfusion of the donor liver. MATERIALS AND METHODS: Potassium levels of 30 consecutive adult patients undergoing cadaveric liver transplantation were assessed before and after liver reperfusion. Changes in potassium levels over 13 predefined timepoints were analyzed. Primary aim: to describe the pattern of change of potassium levels during the reperfusion period. Correlation between changes in potassium levels during reperfusion and a-priori variables were investigated. RESULTS: Baseline median (IQR) potassium levels were 4.1 (3.8:4.5) mmol/L. Thirteen patients (43%) developed hyperkalemia, 10 (33%) of whom developed severe hyperkalemia. Potassium levels peaked at 80 s post reperfusion, plateaued until 2 min, before returning toward baseline values at 5 min. There was a strong association between pre-reperfusion/baseline potassium levels and peak potassium values during reperfusion (95%CI: 0.26 to 0.77, p < 0.001). A baseline potassium level of 4.45 mmol/L was a good predictor of reperfusion hyperkalemia with a sensitivity of 69.2% and specificity of 94.1% (AUC = 0.894, 95%CI: 0.779 to 1.000, p < 0.001). CONCLUSION: Hyperkalemia during cadaveric liver transplantation is common affecting almost 1 in 2 patients during reperfusion. During reperfusion potassium levels peaked within 2 min and over a third of patients developed severe hyperkalemia. Higher peak potassium levels correlated strongly with higher pre-reperfusion potassium values. These findings guide clinicians with timing of sampling of blood to check for hyperkalemia and identify modifiable factors associated with the development of hyperkalemia.

Preoperative Optimization and Choreographed Physiological Evaluation for Resection of Giant Abdominal Neoplasm: A Case Report.

Giant ovarian cystadenoma is a rare and often late presentation. The mass effect of such tumors can lead to profound respiratory and cardiovascular compromise, predominately through inferior vena cava compression, but also restriction of normal lung function through transdiaphragmatic mass effect and, as is seen in this case, cardiac tamponade. In this article, the authors outline an expedited program of preoperative optimization and a choreographed physiological assessment strategy to functionally assess the hemodynamic consequences of a giant ovarian mucinous neoplasm, thereby informing the safe conduct of anesthesia and surgery.