Dynamics of Capillary Lactate Levels in Patients with Out-of-Hospital Cardiac Arrest.

Background and Objectives: An effective strategy for cardiopulmonary resuscitation should be based on tissue perfusion. Our primary aim was to determine the association between capillary lactate values and initial rhythm as well as the probability of the return of spontaneous circulation in out-of-hospital cardiac arrest patients. Materials and Methods: This prospective observational cohort study included all patients with non-traumatic out-of-hospital cardiac arrest, older than 18 years, resuscitated by a prehospital emergency medical team between April 2020 and June 2021. Capillary lactate samples were collected at the time of arrival and every 10 min after the first measurement until the time of the return of spontaneous circulation (ROSC) or, if ROSC was not achieved, at the time of declaring death on the scene. Results: In total, 83 patients were enrolled in the study. ROSC was achieved in 28 patients (33.7%), 21 were admitted to hospital (26.3%), and 6 (7.23%) of them were discharged from hospital. At discharge, all patients had Cerebral Performance Category Scale 1 or 2. Initial capillary lactate values were significantly higher in patients with a non-shockable rhythm compared to the group with a shockable rhythm (9.19 ± 4.6 versus 6.43 ± 3.81; p = 0.037). A significant difference also persisted in a second value taken 10 min after the initial value (10.03 ± 5,19 versus 5.18 ± 3.47; p = 0.019). Capillary lactate values were higher in the ROSC group and non-ROSC group at the time of restored circulation (11.10 ± 6.59 and 6.77 ± 4.23, respectively; p = 0.047). Conclusions: Capillary lactate values are significantly higher in patients with a non-shockable first rhythm in out-of-hospital cardiac arrest (OHCA). There is also a significantly different rise in capillary lactate levels in patients with ROSC.

A way forward in pulmonary aspiration incidence reduction: ultrasound, mathematics, and worldwide data collection

Abstract Aspiration of gastric contents during induction of general anesthesia remains a significant cause of mortality and morbidity in anesthesia. Recent data show that pulmonary aspiration still accounts for many cases with implications on mortality despite technical and technological evolution. Practical, ethical, and methodological issues prevent high-quality research in the setting of aspiration and rapid sequence induction/intubation, and significant controversy is ongoing. Patients' position, drugs choice, dosing and timing, use of cricoid force, and a reliable risk assessment are widely debated with significant questions still unanswered. We focus our discussion on three approaches to promote a better understanding of rapid sequence induction/intubation and airway management decision-making. Firstly, we review how we can use qualitative and quantitative assessment of fasting status and gastric content with the point-of-care ultrasound as an integral part of preoperative evaluation and planning. Secondly, we propose using imaging-based mathematical models to study different patient positions and aspiration mechanisms, including identifying aspiration triggers. Thirdly, we promote the development of a global data collection system aiming to obtain precise epidemiological data. Therefore, we fill the gap between evidence-based medicine and experts' opinion through easily accessible and diffused computer-based databases. A better understanding of aspiration epidemiology obtained through focused global data gathering systems, the widespread use of ultrasound-based prandial status evaluation, and development of advanced mathematical models might potentially guide safer airway management decision making in the 21st century.

A way forward in pulmonary aspiration incidence reduction: ultrasound, mathematics, and worldwide data collection.

Aspiration of gastric contents during induction of general anesthesia remains a significant cause of mortality and morbidity in anesthesia. Recent data show that pulmonary aspiration still accounts for many cases with implications on mortality despite technical and technological evolution. Practical, ethical, and methodological issues prevent high-quality research in the setting of aspiration and rapid sequence induction/intubation, and significant controversy is ongoing. Patients' position, drugs choice, dosing and timing, use of cricoid force, and a reliable risk assessment are widely debated with significant questions still unanswered. We focus our discussion on three approaches to promote a better understanding of rapid sequence induction/intubation and airway management decision-making. Firstly, we review how we can use qualitative and quantitative assessment of fasting status and gastric content with the point-of-care ultrasound as an integral part of preoperative evaluation and planning. Secondly, we propose using imaging-based mathematical models to study different patient positions and aspiration mechanisms, including identifying aspiration triggers. Thirdly, we promote the development of a global data collection system aiming to obtain precise epidemiological data. Therefore, we fill the gap between evidence-based medicine and experts' opinion through easily accessible and diffused computer-based databases. A better understanding of aspiration epidemiology obtained through focused global data gathering systems, the widespread use of ultrasound-based prandial status evaluation, and development of advanced mathematical models might potentially guide safer airway management decision making in the 21st century.

Change in Voice Quality after Radiotherapy for Early Glottic Cancer.

Our aim was to track the changes in voice quality for two years after radiotherapy (RT) for early glottic cancer. A videoendostroboscopy, subjective patient and phoniatrician voice assessments, a Voice Handicap Index questionnaire, and objective acoustic measurements (F0, jitter, shimmer, maximal phonation time) were performed on 50 patients with T1 glottic carcinomas at 3, 12, and 24 months post-RT. The results were compared between the subsequent assessments, and between the assessments at 3 months and 24 months post-RT. The stroboscopy showed a gradual progression of fibrosis of the vocal folds with a significant difference apparent when the assessments at 3 months and 24 months were compared (p < 0.001). Almost all of the subjective assessments of voice quality showed an improvement during the first 2 years, but significant differences were noted at 24 months. Jitter and shimmer deteriorated in the first year after RT with a significant deterioration noticed between the sixth and twelfth months (p = 0.048 and p = 0.002, respectively). Two years after RT, only 8/50 (16%) patients had normal voices. The main reasons for a decreased voice quality after RT for early glottic cancer were post-RT changes in the larynx. Despite a significant improvement in the voice after RT shown in a few of the evaluation methods, only a minority of the patients had a normal voice two years post-RT.

Effects of the reservoir bag disconnection on inspired gases during general anesthesia: a simulator-based study.

BACKGROUND: Fresh gas decoupling is a feature of the modern anesthesia workstation, where the fresh gas flow (FGF) is diverted into the reservoir bag and is not added to the delivered tidal volume, which thus remains constant. The present study aimed to investigate the entraining of the atmospheric air into the anesthesia breathing circuit in case the reservoir bag was disconnected. METHODS: We conducted a simulator-based study, where the METI HPS simulator was connected to the anesthesia workstation. The effect of the disconnected reservoir bag was evaluated using oxygen (O2) and air or oxygen and nitrous oxide (N2O) as a carrier gas at different FGF rates. We disconnected the reservoir bag for 10 min during the maintenance phase. We recorded values for inspiratory O2, N2O, and sevoflurane. The time constant of the exponential process was estimated during reservoir bag disconnection. RESULTS: The difference of O2, N2O and sevoflurane concentrations, before, during, and after reservoir bag disconnection was statistically significant at 0.5, 1, and 2 L/min of FGF (p < 0.001). The largest decrease of the inspired O2 concentrations (FIO2) was detected in the case of oxygen and air as the carrier gas and an FGF of 1 L/min, when oxygen decreased from median [25th-75th percentile] 55.00% [54.00-56.00] to median 39.50% [38.00-42.50] (p < 0.001). The time constant for FIO2 during reservoir bag disconnection in oxygen and air as the carrier gas, were median 2.5, 2.5, and 1.5 min in FGF of 0.5, 1.0, and 2 L/min respectively. CONCLUSIONS: During the disconnection of the anesthesia reservoir bag, the process of pharmacokinetics takes place faster compared to the wash-in and wash-out pharmacokinetic properties in the circle breathing system. The time constant was affected by the FGF rate, as well as the gradient of anesthetic gases between the anesthesia circle system and atmospheric air.

Efficacy of continuous in-wound infusion of levobupivacaine and ketorolac for post-caesarean section analgesia: a prospective, randomised, double-blind, placebo-controlled trial.

BACKGROUND: In-wound catheters for infusion of local anaesthetic for post-caesarean section analgesia are well tolerated in parturients. Few studies have examined continuous in-wound infusion of a combination of local anaesthetic and non-steroidal anti-inflammatory drug for post-caesarean section analgesia. This single centre study evaluated post-operative analgesic efficacy and piritramide-sparing effects of continuous in-wound infusion of either local anaesthetic or non-steroidal anti-inflammatory agent, or the combination of both, versus saline placebo, when added to systemic analgesia with paracetamol. METHODS: After National Ethical Board approval, 59 pregnant women scheduled for non-emergency caesarean section were included in this prospective, randomised, double-blind, placebo-controlled study. The parturients received spinal anaesthesia with levobupivacaine and fentanyl. Post-operative analgesia to 48 h included paracetamol 1000 mg intravenously every 6 h, with the studied agents as in-wound infusions. Rescue analgesia with piritramide was available as needed, titrated to 2 mg intravenously. Four groups were compared, using a subcutaneous multi-holed catheter connected to an elastomeric pump running at 5 mL/h over 48 h. The different in-wound infusions were: levobupivacaine 0.25% alone; ketorolac tromethamine 0.08% alone; levobupivacaine 0.25% plus ketorolac tromethamine 0.08%; or saline placebo. The primary outcome was total rescue piritramide used at 24 h and 48 h post-operatively, under maintained optimal post-caesarean section analgesia. RESULTS: Compared to placebo in-wound infusions, ketorolac alone and levobupivacaine plus ketorolac in-wound infusions both significantly reduced post-operative piritramide consumption at 24 h (p = 0.003; p < 0.001, respectively) and 48 h (p = 0.001; p < 0.001). Compared to levobupivacaine, levobupivacaine plus ketorolac significantly reduced post-operative piritramide consumption at 24 h (p = 0.015) and 48 h (p = 0.021). For levobupivacaine versus ketorolac, no significant differences were seen for post-operative piritramide consumption at 24 h and 48 h (p = 0.141; p = 0.054). CONCLUSION: Continuous in-wound infusion with levobupivacaine plus ketorolac provides greater opioid-sparing effects than continuous in-wound infusion with levobupivacaine alone. TRIAL REGISTRATION: German Clinical Trials Register: retrospectively registered on 30 July, 2014, DRKS 00006559 .

Cerebral tissue oximetry levels during prehospital management of cardiac arrest - A prospective observational study.

INTRODUCTION: Near-infrared spectroscopy (NIRS) enables continuous monitoring of regional oximetry (rSO2). The aim of this study was to describe dynamics of regional cerebral oximetry levels during out of hospital cardiac arrest (OHCA) resuscitation, specifically around the time of restoration of spontaneous circulation (ROSC). METHODS: This prospective observational study was performed in the prehospital setting during cardio-pulmonary resuscitation (CPR) of OHCA patients. In the three-year study period, two-hundred eighty OHCA's were responded to; rSO2 was continuously measured throughout CPR and after attaining ROSC. RESULTS: Final data analysis included 53 patients. Continuous rSO2dynamics were described and data was compared amongst ROSC (22 cases) and no-ROSC (31 cases) groups. Initial rSO2levels were below 15% (not detectable) in both groups. With ongoing CPR, rSO2levels were higher in the ROSC group (median 22% vs. 14% in no-ROSC group, p = 0.030). Until ROSC, rSO2levels were higher throughout CPR before ROSC (mean maximal value 47% at ROSC vs. 31% no-ROSC, p < 0.01). Furthermore, we found a pattern of significant, rapid and sustained rise in rSO2levels minutes prior to ROSC and normalization thereafter. CONCLUSIONS: Initial rSO2levels during OHCA are generally undetectable by the time EMS teams initiate CPR. With CPR, rSO2levels rise and are higher during CPR in patients who later achieve ROSC. Patients who achieve ROSC exhibit significant, rapid, and sustained rise in rSO2minutes prior to attaining ROSC, and normalization of rSO2 levels thereafter. Persistently low levels of rSO2 during CPR likely portend poor neurologic outcomes.

Uncontrolled delivery of liquid volatile anaesthetic when using the anaesthetic conserving device.

During patient sedation with liquid volatile anaesthetic, some problems may occur through a process called auto-pumping, defined as an expansion of bubbles inside the syringe, which can lead to uncontrolled anaesthetic delivery. The study examined how the temperature of liquid volatile anaesthetics (sevoflurane and isoflurane) and the presence of gas bubbles in the syringe affect the occurrence of auto-pumping when using the anaesthetic conserving device (ACD, AnaConDa™, Sedana Medical, Uppsala, Sweden). Four different circumstances for each volatile anaesthetic were tested with a bench study: volatile anaesthetic at room temperature or precooled with and without the presence of gas bubbles in the syringe. Liquid volatile anaesthetic was infused into the ACD via a syringe pump at a fixed rate and heated gradually until the temperature of the syringe surface reached 50 °C. A main-stream gas monitor was used to measure the expired fraction of volatile anaesthetic (FE vol%). The occurrence of auto-pumping was observed only in the subgroups containing gas bubbles, with both anaesthetics. In these subgroups, the values of the expired anaesthetic gas fraction increased dramatically with the expansion of gas bubbles in the syringe (ΔFE ranged from +1.6 to 2.4 vol% for sevoflurane and +2.3 to 3.4 vol% for isoflurane). Furthermore, when the heat source was removed, a substantial decline in anaesthetic agent values below the baseline was observed with both anaesthetics. The presence of gas bubbles in the syringe, especially when exposed to a heat source, may provoke auto-pumping with uncontrolled excessive anaesthetic delivery. If auto-pumping is suspected, the syringe pump must be stopped and the ACD removed from the breathing circuit at once.

Pathophysiology of Myocardial Infarction and Acute Management Strategies.

On an annual basis, 13.2% of all deaths are attributable to coronary artery disease (CAD), which makes CAD - with 7.4 million deaths - the leading cause of death in the world. In this review, we discuss current knowledge in the pathophysiology of atherosclerosis with its progression to stable CAD and its destabilization and complication with thrombus formation - myocardial infarction (MI). Next, we describe mechanisms of myocardial cell death in MI, the ischemia-reperfusion injury, leftventricular remodeling and complications of MI. Furthermore, we add acute management strategies concentrating on medical therapy, a decision on the reperfusion strategy, timing and cardiac protection by ischemic preconditioning, post-conditioning and remote ischemic conditioning.

Point of care ultrasound for orotracheal tube placement assessment in out-of hospital setting.

AIM OF THE STUDY: The percentage of unrecognised orotracheal tube displacement in an out-of-hospital setting has been reported to be between 4.8% and 25%. The aim of our study was to assess the sensitivity and specificity of Point-of-Care-UltraSound (POCUS) for confirming the proper tube position after an urgent orotracheal intubation in an out-of-hospital setting and the time needed for POCUS. METHODS: Our single-centred prospective study included all patients who needed out-of-hospital orotracheal intubation. After the intubation, bilateral chest auscultation and assessment of bilateral lung sliding and diaphragm excursion within POCUS were done. Spectrographic quantitative capnography was used as the reference standard to confirm a proper tube position. RESULTS: We enrolled 124 patients. For auscultation, sensitivity and negative predicted value were 100%, specificity was 90% and positive predicted value 30% (95% confidence interval). Sensitivity, specificity, positive predicted value, and negative predicted value for POCUS alone and for a combination of auscultation and POCUS were 100% (95% confidence interval). In three patients, we detected endobronchial tube displacement with auscultation and POCUS. Capnography failed to detect displacement in all three cases. The median time needed for POCUS was 30s. CONCLUSION: Results of our study support POCUS as an accurate and reliable method for confirming the proper orotracheal tube placement in trachea and it is feasible for out-of-hospital setting implementation. POCUS also seems to be time saving method but to make definitive conclusion more studies should be done.

Influence of body position on hemodynamics in patients with ischemic heart disease undergoing cardiac surgery.

INTRODUCTION: The cardiovascular response to decreased or increased preload in high-risk patients with ischemic heart disease enables us to understand the physiologic response to hemorrhage and its treatment. Although numerous studies have failed to show its effectiveness, the head-down position is still widely used to treat patients with hypotension and shock. The aim of our study was to evaluate the influence of body position on hemodynamics in high-risk patients undergoing coronary artery bypass graft surgery. METHODS: In 16 patients with ischemic hearth disease and poor left ventricular function undergoing coronary artery bypass graft surgery, we measured cardiac output with thermodilution, arterial pressure, central venous pressure (CVP), pulmonary artery wedge pressure (PAWP) and heart rate in three different body positions: the horizontal position, 20 degrees head-up position, 20 degrees head-down position and back in the horizontal position. The measurements were made before and after cardiac surgery. RESULTS: Before skin incision the change from horizontal to 20 degrees head-up position led to a nonsignificant decrease in cardiac output and a significant decrease in mean arterial pressure, CVP and PAWP. The change from 20 degrees head-up to 20 degrees head-down position led to a significant increase in cardiac output, mean arterial pressure, CVP and PAWP. After skin closure the change from horizontal to 20 degrees head-up position led to a nonsignificant decrease in cardiac output and mean arterial pressure and a significant decrease CVP and PAWP. The change from 20 degrees head-up to 20 degrees head-down position led to a nonsignificant increase in cardiac output and a significant increase in mean arterial pressure, CVP and PAWP. There were no significant changes in heart rate during the changes in position before or after surgery. CONCLUSIONS: The results of our study showed a hemodynamic response similar to hemorrhage after placing the patients in a 20 degrees head-up position and improving hemodynamics in the head-down position in mechanically ventilated patients undergoing coronary artery bypass graft surgery.

A randomised controlled trial comparing remifentanil and fentanyl for induction of anaesthesia in CABG surgery.

INTRODUCTION: In a prospective randomised trial we studied haemodynamic stability during induction of anaesthesia for CABG surgery in patients receiving remifentanil-propofol or fentanyl-propofol anaesthesia. METHODS: Fifty-four patients scheduled for elective CABG surgery were studied. Anaesthesia was induced with propofol and pancuronium. The patients were randomly assigned to two groups according to the opioid used during the induction. The remifentanil group received 0.5 microg kg(-1) min(-1) of the drug and the fentanyl group received 5 microg kg(-1). We measured blood pressure, central venous pressure and heart rate continuously for 15 min before and 30 min after orotracheal intubation. We also recorded use of rescue medication for maintaining the mean arterial pressure between 65 and 85 mmHg. RESULTS: After induction of anaesthesia the mean arterial pressure and heart rate decreased significantly in both groups (P<0.05). After orotracheal intubation the mean arterial pressure and heart rate increased significantly in the fentanyl group but not in the remifentanil group (P<0.05). The incidence of hypertonic events necessitating the use of rescue medication was significantly higher in the fentanyl group (P<0.05). CONCLUSIONS: Our results show more stable haemodynamics after induction of anaesthesia in CABG surgery in patients receiving remifentanil-propofol than in patients receiving fentanyl-propofol.