Pasquale Nardelli

Additive Effect on Survival of Anaesthetic Cardiac Protection and Remote Ischemic Preconditioning in Cardiac Surgery: A Bayesian Network Meta-Analysis of Randomized Trials

Introduction Cardioprotective properties of volatile agents and of remote ischemic preconditioning have survival effects in patients undergoing cardiac surgery. We performed a Bayesian network meta-analysis to confirm the beneficial effects of these strategies on survival in cardiac surgery, to evaluate which is the best strategy and if these strategies have additive or competitive effects. Methods Pertinent studies were independently searched in BioMedCentral, MEDLINE/PubMed, Embase, and the Cochrane Central Register (updated November 2013). A Bayesian network meta-analysis was performed. Four groups of patients were compared: total intravenous anesthesia (with or without remote ischemic preconditioning) and an anesthesia plan including volatile agents (with or without remote ischemic preconditioning). Mortality was the main investigated outcome. Results We identified 55 randomized trials published between 1991 and 2013 and including 6,921 patients undergoing cardiac surgery. The use of volatile agents (posterior mean of odds ratio = 0.50, 95% CrI 0.28–0.91) and the combination of volatile agents with remote preconditioning (posterior mean of odds ratio = 0.15, 95% CrI 0.04–0.55) were associated with a reduction in mortality when compared to total intravenous anesthesia. Posterior distribution of the probability of each treatment to be the best one, showed that the association of volatile anesthetic and remote ischemic preconditioning is the best treatment to improve short- and long-term survival after cardiac surgery, suggesting an additive effect of these two strategies. Conclusions In patients undergoing cardiac surgery, the use of volatile anesthetics and the combination of volatile agents with remote preconditioning reduce mortality when compared to TIVA and have additive effects. It is necessary to confirm these results with large, multicenter, randomized, double-blinded trials comparing these different strategies in cardiac and non-cardiac surgery, to establish which volatile agent is more protective than the others and how to best apply remote ischemic preconditioning.

Closed-Loop Delivery Systems Versus Manually Controlled Administration of Total IV Anesthesia: A Meta-analysis of Randomized Clinical Trials.

Bispectral Index Scale (BIS)-guided closed-loop delivery of anesthetics has been extensively studied. We performed a meta-analysis of all the randomized clinical trials comparing efficacy and performance between BIS-guided closed-loop delivery and manually controlled administration of total IV anesthesia. Scopus, PubMed, EMBASE, and the Cochrane Central Register of clinical trials were searched for pertinent studies. Inclusion criteria were random allocation to treatment and closed-loop delivery systems versus manually controlled administration of total IV anesthesia in any surgical setting. Exclusion criteria were duplicate publications and nonadult studies. Twelve studies were included, randomly allocating 1284 patients. Use of closed-loop anesthetic delivery systems was associated with a significant reduction in the dose of propofol administered for induction of anesthesia (mean difference [MD] = 0.37 [0.17–0.57], P for effect <0.00001, P for heterogeneity = 0.001, I2 = 74%) and a significant reduction in recovery time (MD = 1.62 [0.60–2.64], P for effect <0.0001, P for heterogeneity = 0.06, I2 = 47%). The target depth of anesthesia was preserved more frequently with closed-loop anesthetic delivery than with manual control (MD = −15.17 [−23.11 to −7.24], P for effect <0.00001, P for heterogeneity <0.00001, I2 = 83%). There were no differences in the time required to induce anesthesia and the total propofol dose. Closed-loop anesthetic delivery performed better than manual-control delivery. Both median absolute performance error and wobble index were significantly lower in closed-loop anesthetic delivery systems group (MD = 5.82 [3.17–8.46], P for effect <0.00001, P for heterogeneity <0.00001, I2 = 90% and MD = 0.92 [0.13–1.72], P for effect = 0.003, P for heterogeneity = 0.07, I2 = 45%). When compared with manual control, BIS-guided anesthetic delivery of total IV anesthesia reduces propofol requirements during induction, better maintains a target depth of anesthesia, and reduces recovery time.

An International Survey on Noninvasive Ventilation Use for Acute Respiratory Failure in General Non-Monitored Wards

BACKGROUND: Use of noninvasive ventilation (NIV) for the treatment of patients with acute respiratory failure (ARF) has greatly increased in the last decades. In contrast, the increasing knowledge of its effectiveness and physician confidence in managing this technique have been accompanied by a declining number of available ICU beds. As a consequence, the application of NIV outside the ICU has been reported as a growing phenomenon. Previously published surveys highlighted a great heterogeneity in NIV use, clinical indications, settings, and efficacy. Moreover, they revealed a marked heterogeneity with regard to staff training and technical and organizational aspects. We performed the first worldwide web-based survey focused on NIV use in general wards for ARF. METHODS: A questionnaire to obtain data regarding hospital and ICU characteristics, settings and modalities of NIV application and monitoring, estimated outcomes, technical and organizational aspects, and observed complications was developed. The multiple-choice anonymous questionnaire to be filled out online was distributed worldwide by mail, LinkedIn, and Facebook professional groups. RESULTS: One-hundred fifty-seven questionnaires were filled out and analyzed. Respondents were from 51 countries from all 5 continents. NIV application in general wards was reported by 66% of respondents. Treatments were reported as increasing in 57% of cases. Limited training and human resources were the most common reasons for not using NIV in general wards. Overall, most respondents perceived that NIV avoids tracheal intubation in most cases; worsening of ARF, intolerance, and inability to manage secretions were the most commonly reported causes of NIV failure. CONCLUSIONS: Use of NIV in general wards was reported as effective, common, and gradually increasing. Improvement in staff training and introduction of protocols could help to make this technique safer and more common when applied in general wards setting.

The Blue Coma: The Role of Methylene Blue in Unexplained Coma After Cardiac Surgery.

OBJECTIVES Methylene blue commonly is used as a dye or an antidote, but also can be used off label as a vasopressor. Serotonin toxicity is a potentially lethal and often misdiagnosed condition that can result from drug interaction. Mild serotonin toxicity previously was reported in settings in which methylene blue was used as a dye. The authors report 3 cases of life-threatening serotonin toxicity in patients undergoing chronic selective serotonin reuptake inhibitor (SSRI) therapy who also underwent cardiac surgery and received methylene blue to treat vasoplegic syndrome. DESIGN An observational study. SETTING A cardiothoracic intensive care unit (ICU) in a teaching hospital. PARTICIPANTS Three patients who received methylene blue after cardiac surgery, later discovered to be undergoing chronic SSRI therapy. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS All 3 patients received high doses of fentanyl during general anesthesia. They all developed vasoplegic syndrome and consequently were given methylene blue in the ICU. All 3 patients developed serotonin toxicity, including coma, after this administration and diagnostic tests were negative for acute intracranial pathology. Coma lasted between 1 and 5 days. Two patients were discharged from the ICU shortly after awakening, whereas the third patient experienced a complicated postoperative course for concomitant refractory low-cardiac-output syndrome. CONCLUSIONS Patients undergoing chronic SSRI therapy should not be administered methylene blue to treat vasoplegic syndrome.

Percutaneous tracheostomy in patients on anticoagulants

Aims: To determine if percutaneous tracheostomy is safe in critically ill patients treated with anticoagulant therapies. Settings and Design: Single-center retrospective study including all the patients who underwent percutaneous dilatational tracheostomy (PDT) placement over a 1-year period in a 14-bed, cardiothoracic and vascular Intensive Care Unit (ICU). Materials and Methods: Patients demographics and characteristics, anticoagulant and antiplatelet therapies, coagulation profile, performed technique and use of bronchoscopic guidance were retrieved. Results: Thirty-six patients (2.7% of the overall ICU population) underwent PDT over the study period. Twenty-six (72%) patients were on anticoagulation therapy, 1 patient was on antiplatelet therapy and 2 further patients received prophylactic doses of low molecular weight heparin. Only 4 patients had normal coagulation profile and were not receiving anticoagulant or antiplatelet therapies. Overall, bleeding of any severity complicated 19% of PDT. No procedure-related deaths occurred. Conclusions: PDT was proved to be safe even in critically ill-patients treated with anticoagulant therapies. Larger prospective studies are needed to confirm our findings.

Pulmonary Complications After Open Abdominal Aortic Surgery: A Systematic Review and Meta-Analysis

OBJECTIVES Postoperative pulmonary complications (PPC) are among the most common complications after noncardiac surgery. Men, smokers, and elderly patients with chronic obstructive pulmonary disease or heart failure are more likely to experience PPC. The majority of patients undergoing vascular surgery belong in these categories and are at higher risk of developing PPC. Moreover, the surgical site is one of the most important risk factors associated with PPC, and aortic surgery carries the highest risk. The aim of this systematic review was to obtain an additional understanding of the real incidence of PPC after open abdominal aortic surgery and the impact of PPC on survival. DESIGN Systematic review and meta-analysis. SETTING Hospitals PARTICIPANTS: Patients who underwent open abdominal aortic surgery. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS A literature search was performed on BioMedCentral, PubMed, Embase, and the Cochrane Register of clinical trials. All prospective or retrospective studies reporting data on PPC after open abdominal aortic surgery were included. Co-primary endpoints were the PPC rate and the correlation between PPC and perioperative mortality. The secondary endpoint was the difference in the PPC rate and mortality between elective and urgent surgery. Data on 269,637 patients from 213 studies were analyzed. The overall median incidence of PPC was 10.3% (interquartile range 5.55%-19.1%). Pneumonia, respiratory insufficiency, prolonged mechanical ventilation, need for unplanned mechanical ventilation, atelectasis, acute respiratory distress syndrome, pulmonary edema, and pleural effusions were the most common PPC reported in the literature. Occurrence of PPC was associated with postoperative mortality (r = 0.65, p<0.01) and was significantly higher in urgent procedures (p<0.001). CONCLUSIONS Incidence of PPC after open abdominal aortic surgery is high and is associated with increased postoperative morbidity and mortality.

The dentist who sat on her chair and lost a leg. N2O

A 35-year-old female dentist laid on her chair to test an N2O machine, and after only a few minutes of inhaling the N2O, she developed acute pyramidal syndrome. The patient started walking again eight months later, but still suffers from lower limb motor deficit, in spite of intensive re-habilitation. Genetic tests later showed that the patient had Type 3 homocystinuria. This is the first case report of acute neu-rological toxicity after brief administration of N2O. We suggest starting vitamin B12 and folic acid supplements promptly in pa-tients who experience neurological symp-toms after receiving N2O.

Noninvasive Ventilation Outside the ICU

The use of noninvasive ventilation (NIV) for the treatment of patients with acute respiratory failure has greatly increased. The growing knowledge of NIV efficacy and clinicians’ confidence in managing this technique have been accompanied by a wide reduction in the number of available intensive care unit (ICU) beds. Therefore, the application of NIV outside the ICU is common and increasing worldwide.

High-frequency oscillatory ventilation

High frequency oscillatory ventilation is characterized by very low tidal volumes, often smaller than anatomic death space, and high respiratory frequencies (3–15 Hz). This strategy was thought to reduce ventilator induced lung injury, avoiding volutrauma and barotrauma. According to most recent data, high frequency oscillatory ventilation does not offer any real advantage when compared to current protective lung ventilation. Moreover it is associated with an increased need for sedative and neuromuscular blocker drugs, unstable hemodynamics and lung barotrauma. The OSCILLATE trial demonstrated an increased risk of death in patients undergoing high frequency oscillatory ventilation. Therefore, high frequency oscillatory ventilation should be avoided as a first-line treatment in patients with acute respiratory distress syndrome.

Glutamine Supplementation in Critically Ill Patients

Glutamine supplementation in intensive care unit patients is supposed to improve outcome by modulating inflammatory response, preventing organ injury, modulating glucose metabolism and inducing cellular protection pathways. Trials showed conflicting results on mortality. Heyland et al showed a significant increase in mortality in critically ill patients who received glutamine supplementation. Their results were confirmed by a subsequent meta-analysis considering only high quality evidence. Therefore, glutamine supplementation should be avoided in this setting.