Ventilatory associated barotrauma in COVID-19 patients: A multicenter observational case control study (COVI-MIX-study).

BACKGROUND: The risk of barotrauma associated with different types of ventilatory support is unclear in COVID-19 patients. The primary aim of this study was to evaluate the effect of the different respiratory support strategies on barotrauma occurrence; we also sought to determine the frequency of barotrauma and the clinical characteristics of the patients who experienced this complication. METHODS: This multicentre retrospective case-control study from 1 March 2020 to 28 February 2021 included COVID-19 patients who experienced barotrauma during hospital stay. They were matched with controls in a 1:1 ratio for the same admission period in the same ward of treatment. Univariable and multivariable logistic regression (OR) were performed to explore which factors were associated with barotrauma and in-hospital death. RESULTS: We included 200 cases and 200 controls. Invasive mechanical ventilation was used in 39.3% of patients in the barotrauma group, and in 20.1% of controls (p<0.001). Receiving non-invasive ventilation (C-PAP/PSV) instead of conventional oxygen therapy (COT) increased the risk of barotrauma (OR 5.04, 95% CI 2.30 - 11.08, p<0.001), similarly for invasive mechanical ventilation (OR 6.24, 95% CI 2.86-13.60, p<0.001). High Flow Nasal Oxygen (HFNO), compared with COT, did not significantly increase the risk of barotrauma. Barotrauma frequency occurred in 1.00% [95% CI 0.88-1.16] of patients; these were older (p=0.022) and more frequently immunosuppressed (p=0.013). Barotrauma was shown to be an independent risk for death (OR 5.32, 95% CI 2.82-10.03, p<0.001). CONCLUSIONS: C-PAP/PSV compared with COT or HFNO increased the risk of barotrauma; otherwise HFNO did not. Barotrauma was recorded in 1.00% of patients, affecting mainly patients with more severe COVID-19 disease. Barotrauma was independently associated with mortality. TRIAL REGISTRATION: this case-control study was prospectively registered in clinicaltrial.gov as NCT04897152 (on 21 May 2021).

Postoperative complications after minimally invasive esophagectomy in the prone position: any anesthesia-related factor?

OBJECTIVE: To evaluate the incidence of postoperative complications arising within 30 days of minimally invasive esophagectomy in the prone position with total lung ventilation and their relationship with 30-day and 1-year mortality. Secondary outcomes included possible anesthesia-related factors linked to the development of complications. METHODS: The study is a retrospective single-center observational study at the Anesthesia and Surgical Department of a tertiary care center in the northeast of Italy. Patients underwent cancer resection through esophagectomy in the prone position without one-lung ventilation. RESULTS: We included 110 patients from January 2010 to December 2017. A total of 54% of patients developed postoperative complications that increased mortality risk at 1 year of follow-up. Complications postponed first oral intake and delayed patient discharge to home. Positive intraoperative fluid balance was related to increased mortality and the risk to develop postoperative complications. C-reactive protein at third postoperative day may help detect complication onset. CONCLUSIONS: Complication onset has a great impact on mortality after esophagectomy. Some anesthesia-related factors, mainly fluid balance, may be associated with postoperative mortality and morbidity. These factors should be carefully taken into account to obtain better outcomes after esophagectomy in the prone position without one-lung ventilation.

Airway management in anesthesia for thoracic surgery: a "real life" observational study.

BACKGROUND: One-lung ventilation (OLV) in thoracic anesthesia is required to provide good surgical exposure. OLV is commonly achieved through a double lumen tube (DLT) or a bronchial blocker (BB). Malposition is a relevant issue related to these devices use. No prospective studies with adequately large sample size have been performed to evaluate the malposition rate of DLTs and BBs. METHODS: A total of 2,127 patients requiring OLV during thoracic surgery were enrolled. The aim of this multicenter prospective observational study performed across 26 academic and community hospitals is to evaluate intraoperative malposition rate of DLTs and BBs. We also aim to assess: which device is the most used to achieve OLV, the frequency of bronchoscope (BRO) use, the incidence rate of desaturation during OLV and the role of other factors that can correlate to this event, and incidence of difficult airway. RESULTS: Malposition rate for DLTs was 14%, for BBs 33%. DLTs were used in 95% of patients and BBs in 5%. Mean positioning time was shorter for DLT than BB (156±230 vs. 321±290 s). BRO was used in 54% of patients to check the correct positioning of the DLT. Desaturation occurred in 20% of all cases during OLV achieved through a DLT. Predicting factors of desaturation were dislocation (OR 2.03) and big size of DLT (OR 1.15). BRO use (OR 0.69) and left surgical side (OR 0.41) proved to be protective factors. Difficult airway prevalence was 16%; 10.8% predicted and 5.2% unpredicted. CONCLUSIONS: DLT has a low malpositioning rate and is the preferred device to achieve OLV. BRO use recorded was unexpectedly low. The possibility of encountering a difficult airway is frequent, with an overall prevalence of 16%. Risk factors of desaturation are malposition and increased size of DLT. Left procedures and BRO use could lead to fewer episodes of desaturation.

Functional fibrinogen (FLEV-TEG) versus the Clauss method in an obstetric population: a comparative study.

BACKGROUND: Hemostasis is the dynamic equilibrium between coagulation and fibrinolysis. During pregnancy, the balance shifts toward a hypercoagulative state; however placental abruption and abnormal placentations may lead to rapidly evolving coagulopathy characterized by the increased activation of procoagulant pathways. These processes can result in hypofibrinogenemia, with fibrinogen levels dropping to 2 g/L or less and an associated increased risk of post-partum hemorrhage. The aim of the present study was to evaluate the concordance between two methods of functional fibrinogen measurement: the Thromboelastography (TEG) method (also known as FLEV) vs. the Clauss method. Three patient groups were considered: healthy volunteers; non-pathological pregnant patients; and pregnant patients who went on to develop postpartum hemorrhage. METHODS: A prospective observational study. Inclusion criteria were: healthy volunteer women of childbearing age, non-pathological pregnant women at term, and pregnant hemorrhagic patients subjected to elective or urgent caesarean section (CS), with blood loss exceeding 1000 mL. Exclusion criteria were age < 18 years, a history of coagulopathy, and treatment with contraceptives, anticoagulants, or antiplatelet agents. RESULTS: Bland-Altman plots showed a significant overestimation with the FLEV method in all three patient groups: bias was - 133.36 mg/dL for healthy volunteers (95% IC: - 257.84; - 8.88. Critical difference: 124.48); - 56.30 mg/dL for healthy pregnant patients (95% IC: - 225.53; 112.93. Critical difference: 169.23); and - 159.05 mg/dL for hemorrhagic pregnant patients (95% IC: - 333.24; 15.148. Critical difference: 174.19). Regression analyses detected a linear correlation between FLEV and Clauss for healthy volunteers, healthy pregnant patients, and hemorrhagic pregnant patients (R2 0.27, p value = 0.002; R2 0.31, p value = 0.001; R2 0.35, p value = 0.001, respectively). ANOVA revealed a statistically significant difference in fibrinogen concentration between all three patients groups when assayed using the Clauss method (p value < 0.001 for all the comparisons), but no statistically significant difference between the two patients groups of pregnant women when using the FLEV method. CONCLUSIONS: The FLEV method does not provide a valid alternative to the Clauss method due to the problem of fibrinogen overestimation, and for this reason it should not be recommended for the evaluation of patients with an increased risk of hypofibrinogenemia.

Cardiac output measurement in liver transplantation patients using pulmonary and transpulmonary thermodilution: a comparative study.

During liver transplantation surgery, the pulmonary artery catheter-despite its invasiveness-remains the gold standard for measuring cardiac output. However, the new EV1000 transpulmonary thermodilution calibration technique was recently introduced into the market by Edwards LifeSciences. We designed a single-center prospective observational study to determine if these two techniques for measuring cardiac output are interchangeable in this group of patients. Patients were monitored with both pulmonary artery catheter and the EV1000 system. Simultaneous intermittent cardiac output measurements were collected at predefined steps: after induction of anesthesia (T1), during the anhepatic phase (T2), after liver reperfusion (T3), and at the end of the surgery (T4). The 4-quadrant and polar plot techniques were used to assess trending ability between the two methods. We enrolled 49 patients who underwent orthotopic liver transplantation surgery. We analyzed a total of 588 paired measurements. The mean bias between pulmonary artery catheter and the EV1000 system was 0.35 L/min with 95% limits of agreement of - 2.30 to 3.01 L/min, and an overall percentage error of 35%. The concordance rate between the two techniques in 4-quadrant plot analysis was 65% overall. The concordance rate of the polar plot showed an overall value of 83% for all pairs. In the present study, in liver transplantation patients we found that intermittent cardiac output monitoring with EV1000 system showed a percentage error compared with pulmonary artery catheter in the acceptable threshold of 45%. On the others hand, our results showed a questionable trending ability between the two techniques.

The Possible Use of Preoperative Natriuretic Peptides for Discriminating Low Versus Moderate-High Surgical Risk Patient.

Perioperative risk scores for patients undergoing noncardiac surgery are generally considered inaccurate, poor, or, at best, modest. We propose estimating a patient's pretest and posttest probability of cardiac morbidity and death using the preoperative scoring system plus the negative likelihood ratio from brain natriuretic peptide (BNP) or N-terminal proB-type natriuretic peptide (NT-proBNP) plasma levels. Our clinical challenge scenario showed a pretest probability of postoperative major cardiac complications with the patient risk factor as 6.6% for the Revised Cardiac Risk Index and between 1% and 5% (intermediate risk) per the recent European Society of Cardiology and the European Society of Anesthesiologist guidelines for surgical risk estimation. In fact, the American College of Cardiology and the American Heart Association guidelines consider the same surgical procedure for elevated risk. The posttest probability takes advantage of a negative likelihood ratio from BNP plasma levels, with patient risk factor reduced to 0.8% and surgical risk to 1.1%. In the same way, the pretest American College of Surgeons National Surgical Quality Improvement Program score decreased from 18.8% to 3.5% for severe complications and from 0.9% to 0.1% for death at ≤90 days. Following noncardiac surgery, postoperative complications and mortality are often cardiac in nature. The negative likelihood ratio of BNP and NT-proBNP plasma levels provides a quick, low-cost tool for recognizing and reclassifying the cardiovascular risk of those undergoing noncardiac surgery, thereby singling out low- versus moderate-high-risk surgical patients.