Optimization of kidney function in cardiac surgery patients with intra-abdominal hypertension: expert opinion.

Cardiac surgery-associated acute kidney injury (CSA-AKI) affects up to 42% of cardiac surgery patients. CSA-AKI is multifactorial, with low abdominal perfusion pressure often overlooked. Abdominal perfusion pressure is calculated as mean arterial pressure minus intra-abdominal pressure (IAP). IAH decreases cardiac output and compresses the renal vasculature and renal parenchyma. Recent studies have highlighted the frequent occurrence of IAH in cardiac surgery patients and have linked the role of low perfusion pressure to the occurrence of AKI. This review and expert opinion illustrate current evidence on the pathophysiology, diagnosis, and therapy of IAH and ACS in the context of AKI.

Continuous Urine Output-Based Alert Identifies Cardiac Surgery-associated Acute Kidney Injury Earlier Than Serum Creatinine: A Prospective and Retrospective Observational Study.

OBJECTIVE(S): Acute kidney injury (AKI) is defined and staged by reduced urine output (UO) and increased serum creatinine (SCr). UO is typically measured manually and documented in the electronic health record, making early and reliable detection of oliguria-based AKI and electronic data extraction challenging. The authors investigated the diagnostic performance of continuous UO, enabled by active drain line clearance-based alerts (Accuryn AKI Alert), compared with AKI stage 2 SCr criteria and their associations with length of stay, need for continuous renal replacement therapy, and 30-day mortality. DESIGN: This study was a prospective and retrospective observational study. SETTING: Nine tertiary centers participated. PARTICIPANTS: Cardiac surgery patients were enrolled. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: A total of 522 patients were analyzed. AKI stages 1, 2, and 3 were diagnosed in 32.18%, 30.46%, and 3.64% of patients based on UO, compared with 33.72%, 4.60%, and 3.26% of patients using SCr, respectively. Continuous UO-based alerts diagnosed stage ≥1 AKI 33.6 (IQR =15.43, 95.68) hours before stage ≥2 identified by SCr criteria. A SCr-based diagnosis of AKI stage ≥2 has been designated a Hospital Harm by the Centers for Medicare & Medicaid Services. Using this criterion as a benchmark, AKI alerts had a discriminative power of 0.78. The AKI Alert for stage 1 was significantly associated with increased intensive care unit and hospital length of stay and continuous renal replacement therapy, and stage ≥2 alerts were associated with mortality. CONCLUSIONS: AKI Alert, based on continuous UO and enabled by active drain line clearance, detected AKI stages 1 and 2 before SCr criteria. Early AKI detection allows for early kidney optimization, potentially improving patient outcomes.

Red Blood Cell Transfusion and Postoperative Delirium in Hip Fracture Surgery Patients: A Retrospective Observational Cohort Study.

BACKGROUND: Patients having hip fracture surgery are at high risk for postoperative delirium. Red blood cell (RBC) transfusion may increase postoperative delirium risk by causing neuroinflammation. We hypothesized that RBC transfusion would be associated with postoperative delirium in patients having hip fracture surgery. METHODS: An observational cohort study was performed using the United States National Surgical Quality Improvement Program (NSQIP) participant use files for hip fracture from 2016 to 2018. Propensity score analysis and inverse probability of treatment weighting (IPTW) were used to reduce bias from confounding. An IPTW adjusted odds ratio for developing postoperative delirium was calculated for patients who received RBC transfusion during surgery or in the 72 hours after. RESULTS: There were 20,838 patients who had eligible current procedural terminology (CPT) codes for primary hip fracture surgery and complete study data. After employing strict exclusions to balance covariates and reduce bias, 3,715 patients remained in the IPTW cohort. Of these, 626 patients (16.9%) received RBC transfusion and 665 patients (17.9%) developed postoperative delirium. IPTW adjustment led to good covariate balance between patients who received RBC transfusion and those who did not. Patients who received RBC transfusion had significantly higher odds of postoperative delirium, IPTW adjusted odds ratio = 1.21, 95% CI = 1.03 to 1.43, and P = 0.02. Discharge location also differed significantly between patients who received RBC transfusion and those who did not (P < 0.001) with in-hospital mortality or referral to hospice occurring in 1.6% of patients who received RBC transfusion and 1.3% of patients who were not transfused. CONCLUSION: RBC transfusion is associated with increased odds of postoperative delirium after hip fracture surgery and may be associated with worse clinical outcome.

Association of prehospital antiplatelet therapy with survival in patients hospitalized with COVID-19: A propensity score-matched analysis.

PURPOSE: Coronavirus disease 2019 (COVID-19) is associated with hypercoagulability and increased thrombotic risk. The impact of prehospital antiplatelet therapy on in-hospital mortality is uncertain. METHODS: This was an observational cohort study of 34 675 patients ≥50 years old from 90 health systems in the United States. Patients were hospitalized with laboratory-confirmed COVID-19 between February 2020 and September 2020. For all patients, the propensity to receive prehospital antiplatelet therapy was calculated using demographics and comorbidities. Patients were matched based on propensity scores, and in-hospital mortality was compared between the antiplatelet and non-antiplatelet groups. RESULTS: The propensity score-matched cohort of 17 347 patients comprised of 6781 and 10 566 patients in the antiplatelet and non-antiplatelet therapy groups, respectively. In-hospital mortality was significantly lower in patients receiving prehospital antiplatelet therapy (18.9% vs. 21.5%, p < .001), resulting in a 2.6% absolute reduction in mortality (HR: 0.81, 95% CI: 0.76-0.87, p < .005). On average, 39 patients needed to be treated to prevent one in-hospital death. In the antiplatelet therapy group, there was a significantly lower rate of pulmonary embolism (2.2% vs. 3.0%, p = .002) and higher rate of epistaxis (0.9% vs. 0.4%, p < .001). There was no difference in the rate of other hemorrhagic or thrombotic complications. CONCLUSIONS: In the largest observational study to date of prehospital antiplatelet therapy in patients with COVID-19, there was an association with significantly lower in-hospital mortality. Randomized controlled trials in diverse patient populations with high rates of baseline comorbidities are needed to determine the ultimate utility of antiplatelet therapy in COVID-19.

Multivariate predictors of blood product use in cardiac surgery.

OBJECTIVE: To determine factors associated with an increased risk of post-cardiopulmonary bypass (CPB) blood product usage in adult cardiac surgical patients. DESIGN: Prospective observational study. SETTING: Academic hospital. PARTICIPANTS: Patients undergoing cardiac surgery with CPB were studied over a 7-month period. INTERVENTIONS: The outcomes studied were receipt of more than 2 U of packed red blood cells (PRBCs), receipt of any other blood component products (cryoprecipitate, fresh-frozen plasma [FFP], or platelets), or surgical re-exploration for bleeding. Preoperative and intraoperative risk factors for bleeding were analyzed. MEASUREMENTS AND MAIN RESULTS: Increased age and preoperative creatinine level, low body surface area, preoperative hematocrit, nonelective surgery, lower temperature on bypass, and duration of bypass were associated with an increased risk of transfusion of >2 U of PRBCs. Low body surface area, repeat surgery, nonelective surgery, and CPB time were associated with transfusion of platelets, fresh-frozen plasma, or cryoprecipitate and/or surgical re-exploration. The following factors were associated with neither transfusion of more than 2 U of PRBC nor transfusion of platelets, FFP or cryoprecipitate, or surgical re-exploration: gender, preoperative international normalized ratio, preoperative antiplatelet medications, and preoperative intravenous heparin. CONCLUSION: Therapies aimed at reducing transfusion of blood products should be aimed at those patients with low body surface areas, baseline anemia, and those undergoing long or repeat surgeries.

Anesthetic implications of the addition of an operative robot for endoscopic surgery: a case report.

Laparoscopic surgery has become increasingly popular over the last decade. However, this surgical technique has a number of limitations. It is difficult to work in a three-dimensional space while viewing a two-dimensional monitor, long instruments amplify natural tremor, and traditional instruments have limited mobility due to few degrees of freedom. Robot-assisted surgery has been developed in response to these limitations. A three-dimensional viewer allows the surgeon to operate in a realistic environment, natural tremor is eliminated by translating the surgeon's hand motions to robotic movements, and the robotic surgical instruments are designed to have the same dexterity as a human wrist. We describe a case of robot-assisted laparoscopic Nissen fundoplication and discuss the anesthetic issues associated with this new surgical technique. In addition to the anesthetic issues associated with traditional laparoscopic surgery, robot-assisted laparoscopic surgery presents some unique challenges.