Impact of anesthetic management on catheter ablation for premature ventricular complexes: insights during the COVID-19 outbreak.

BACKGROUND: The influence of divergent anesthesia types during ablation of premature ventricular complexes (PVCs) is not known. While previously performed under general anesthesia (GA) at our institution, these procedures were exclusively performed under local anesthesia (LA) ± minimal sedation during the COVID-19 outbreak for logistic reasons. METHODS: One hundred and eight consecutive patients (82 GA versus 26 LA) undergoing PVC ablation at our center were evaluated. Intraprocedural PVC burden (over 3 min) pre-ablation was measured twice: (1) at the start (before GA induction) and (2) before catheter insertion (after GA induction). Upon cessation of ablation and after a waiting period of ≥ 15 min, acute ablation success (AAS) was defined as absence of PVCs until the end of the recording period. RESULTS: Intraprocedural PVC burden was not significantly different between LA versus GA group: (1) 17.8 ± 3% vs 12.7 ± 2%, P = 0.17 and (2) 10.0 ± 3% vs 7.4 ± 1%, P = 0.43, respectively. Activation mapping-based ablation was performed significantly more in the LA vs GA group (77% vs 26% of patients, P < 0.001, respectively). AAS was significantly higher in LA vs GA group: 22/26 (85%) vs 41/82 (50%), respectively, P < 0.01. After multivariable analysis, LA was the only independent predictor for AAS (OR 13, 95% CI 1.57-107.4, P = 0.017). CONCLUSION: Ablation of PVC under LA presented significantly higher AAS rate compared to GA. The procedure under GA might be complicated by PVC inhibition (after catheter insertion/during mapping) and PVC disinhibition post-extubation.

Effect of extracorporeal carbon dioxide removal on respiratory quotient measured by indirect calorimetry: Unravelling the mystery.

NEW FINDINGS: What is the main observation in this case? Several studies have reported progressive hypoxaemia once extracorporeal carbon dioxide removal is started in patients with hypercapnic respiratory failure, possibly attributable to an altered respiratory quotient. What insights does it reveal? In this quality control report, we show that the respiratory quotient exhibits only minimal alteration when extracorporeal carbon dioxide removal is started and assume that the progressive hypoxaemia is attributable to an increase in intrapulmonary shunt. ABSTRACT: The use of extracorporeal carbon dioxide removal (ECCO2 R) has been proposed in patients with acute respiratory distress syndrome to achieve lung-protective ventilation and in patients with selective hypercapnic respiratory failure. However, several studies have reported progressive hypoxaemia, as expressed by a need to increase the inspired oxygen fraction (Fi O2 ) to maintain adequate oxygenation or by a decrease in the ratio of arterial oxygen tension (Pa O2 ) to Fi O2 once ECCO2 R is started. We present the case of a patient who was admitted to the intensive care unit for a coronavirus disease 2019 pneumonia and who was intubated because of hypercapnic respiratory insufficiency. Extracorporeal carbon dioxide removal was started, and the patient subsequently developed progressive hypoxaemia. To test whether the hypoxaemia was attributable to the ECCO2 R, blood samples were taken in different settings: (1) 'no ECCO2 R', blood flow 150 ml/min with a ECCO2 R gas flow of 0 L/min; and (2) 'with ECCO2 R', blood flow 400 ml/min with gas flow 12 L/min. We measured Pa O2 , alveolar oxygen tension, Pa O2 /Fi O2 , alveolar-arterial oxygen tension difference, arterial carbon dioxide tension and the respiratory quotient (RQ) by indirect calorimetry in each setting. The RQ was 0.60 without ECCO2 R and 0.57 with ECCO2 R. The alveolar oxygen tension was 220.4 mmHg without ECCO2 R and increased to 240.3 mmHg with ECCO2 R, whereas Pa O2 /Fi O2 decreased from 177 to 171. Our study showed only a minimal change in RQ when ECCO2 R was started. We were the first to measure the RQ directly, before and after the initiation of ECCO2 R, in a patient with hypercapnic respiratory failure.

Percutaneous tracheostomy for long-term ventilated COVID-19-patients: rationale and first clinical-safe for all-experience.

INTRODUCTION: COVID-19 infection has resulted in thousands of critically ill patients admitted to ICUs and treated with mechanical ventilation. Percutaneous tracheostomy is a well-known technique utilised as a strategy to wean critically ill patients from mechanical ventilation. Worldwide differences exist in terms of methods, operators, and settings, and questions remain regarding timing and indications. If tracheostomy is to be performed in COVID-19 patients, a safe environment is needed for optimal care. MATERIAL AND METHODS: We present a guidewire dilating forceps tracheostomy procedure in COVID-19 patients that was optimised including apnoea-moments, protective clothing, checklists, and clear protocols. We performed a retrospective analysis of the outcome after tracheostomy in COVID-19 patients between March 2020 and May 2020. RESULTS: The follow-up of the first 16 patients, median age 62 years, revealed a median intubation time until tracheostomy of 18 days and median cannulation time of 20 days. The overall perioperative complication rate and complication rate while cannulated was 19%, mainly superficial bleeding. None of the healthcare providers involved in performing the procedure developed any symptoms of the disease. CONCLUSIONS: This COVID-19-centred strategy based on flexibility, preparation, and cooperation between healthcare providers with different backgrounds facilitated percutaneous tracheostomy in COVID-19 patients without an increase in the overall complication rate or evidence of risk to healthcare providers. Our findings provide initial evidence that tracheostomy can be performed safely as a standard of care for COVID-19 patients requiring prolonged mechanical ventilation as was standard practice in ICU patients prior to the COVID-19 pandemic to promote ventilator weaning and patient recovery.

Signs of post-traumatic hypovolemia on abdominal CT and their clinical importance: A systematic review.

PURPOSE: Our aim was to assess the findings of hypovolemia on abdominal CT that are most frequently seen in blunt abdominal trauma patients. When possible, we assessed the correlation of these CT signs with clinical outcome. METHODS: MEDLINE, CENTRAL and EMBASE were systematically searched. Two reviewers independently screened and included articles and performed the data-extraction. Primary outcomes of interest were the frequency of each sign and its correlation with mortality. Secondary outcomes were need for intervention, transfusion need, intensive care unit admission rate and length of stay. RESULTS: A flat inferior vena cava and an inferior vena cava halo, a diminished aortic calibre, shock bowel, altered enhancement of the liver, pancreas, adrenals, kidneys, spleen and gallbladder, peripancreatic fluid and splenic volume changes have been described in the setting of hypovolemic trauma patients to constellate a CT hypovolemic shock complex. It is argued that vascular signs represent the true hypovolemic state and the visceral signs represent hypoperfusion. There is no consensus on the frequency or clinical relevance of these signs, which at least partly can be explained by the heterogeneity in study design, study population, scanning protocols and outcome parameters. Available evidence suggests a good predictive value for occult shock and a higher mortality rate when a flat inferior vena cava is present. Evidence regarding the other signs is scarce. CONCLUSIONS: The hypovolemic shock complex is an entity of both vascular and visceral CT signs that can be seen in blunt trauma patients. It can offer guidance to a swift primary imaging survey in the acute trauma setting, allowing the radiologist to alert the treating physicians to possible pending hypovolemic shock.

Safety of gelatin solutions for the priming of cardiopulmonary bypass in cardiac surgery: a systematic review and meta-analysis.

This systematic review and meta-analysis was conducted to evaluate the safety of gelatin versus hydroxyethyl starches (HES) and crystalloids when used for cardiopulmonary bypass (CPB)-priming in cardiac surgery. MEDLINE (Pubmed), Embase and CENTRAL were searched. We included only randomized, controlled trials comparing CPB-priming with gelatin with either crystalloids or HES-solutions of the newest generation. The primary endpoint was the blood loss during the first 24 hours. Secondary outcomes included perioperative transfusion requirements, postoperative kidney function, postoperative ventilation times and length of stay on the intensive care unit. Sixteen studies were identified, of which only ten met the inclusion criteria, representing a total of 824 adult patients: 4 studies compared gelatin with crystalloid, and 6 studies gelatin with HES priming. Only 2 of the studies comparing HES and gelatin reported postoperative blood loss after 24 hours. No significant difference in postoperative blood loss was found when results of both studies were pooled (SMD -0.12; 95% CI: -0.49, 0.25; P=0.52). Likewise, the pooled results of 3 studies comparing gelatin and crystalloids as a priming solution could not demonstrate significant differences in postoperative bleeding after 24 hours (SMD -0.07; 95% CI: -0.40, 0.26; P=0.68). No differences regarding any of the secondary outcomes could be identified. This systematic review suggests gelatins to have a safety profile which is non-inferior to modern-generation tetrastarches or crystalloids. However, the grade of evidence is rated low owing to the poor methodological quality of the included studies, due to inconsistent outcome reporting and lack of uniform endpoint definitions.

Performance of an active inspired hypoxic guard.

Current hypoxic guards systems fail to maintain the inspired O2 concentration (FIO2) ≥ 21 % across the entire fresh gas flow (FGF) range when a second carrier gas is used (N2O or air). We examined the performance of the Maquet O2 Guard(®), a smart hypoxic guard that increases O2 delivery if an inspired hypoxic mixture is formed. After obtaining IRB approval and informed consent, 12 ASA I-II patients were enrolled. During anesthesia with sevoflurane in O2/air, the O2 Guard(®) was tested by administering O2/air at the following delivered hypoxic guard limits [expressed as (total FGF in L min(-1); FDO2 in %)] for 4 min each: [0.3;67], [0.4;50], [0.6;34], [0.8;25], [1.0;21], [1.2;21], [1.5;21], [2;21], [3;21], and [5;21]. The following data were collected: (1) time from FIO2 = 30 to 20 %; (2) time from FIO2 = 20 % to O2 Guard(®) activation; (3) time from O2 Guard(®) activation to FIO2 = 25 %; (4) FGF and FDO2 used by the O2 Guard. If SpO2 was <90 % for 10 s or longer at any time, the patient was excluded. Three patients were excluded for low SpO2. The incidence of FIO2 < 21 % was 100 % within the 1-2 L min(-1) FGF range. The O2 Guard(®) was activated within 20 s after FIO2 became 20 %, except in one patient where FIO2 oscillated between 20 and 21 %. FDO2 was increased to 60 % and FGF to 1 L min(-1) (the latter only if it was lower than 1 L min(-1) prior to activation of the O2 Guard). FIO2 increased to 25 % within 55 s after O2 Guard activation in all patients. The O2 Guard(®), an active inspired hypoxic guard, rapidly reverses and limits the duration of inspired hypoxic episodes when the delivered hypoxic guard fails to do so.