End-tidal carbon dioxide

BACKGROUND: Measuring arterial partial pressure of carbon dioxide (PaCO2 ) is crucial for proper mechanical ventilation, but the current sampling method is invasive. End-tidal carbon dioxide (EtCO2 ) has been used as a surrogate, which can be measured non-invasively, but its limited accuracy is due to ventilation-perfusion mismatch. This study aimed to develop a non-invasive PaCO2 estimation model using machine learning. METHODS: This retrospective observational study included pediatric patients (< 18 years) admitted to the pediatric intensive care unit of a tertiary children's hospital and received mechanical ventilation between January 2021 and June 2022...

Waveform capnography is a noninvasive measurement of ventilation and perfusion commonly employed in the prehospital setting. It is easy to apply, and modern cardiac monitors are equipped with the necessary ports and capability to display results. Despite its ease of use, end-tidal CO2 monitoring has not yet achieved widespread adoption within the hospital setting. It is routinely used in the emergency department and by anesthesiologists, but its application could support ICU management in critically ill patients...

OBJECTIVES: Chiari type 1 malformation (CM1) may occasionally lead to central sleep apnea (CSA). We studied, in a large clinical cohort of pediatric CM1 patients, the effect of CM1 on breathing during sleep. METHODS: This is a retrospective single pediatric pulmonology center study with a systematic evaluation of pediatric CM1 patients under age 18 with polysomnography (PSG) during 2008-2020. Children with syndromes were excluded. All patients had undergone head and spine magnetic resonance imaging...

BACKGROUND: Several noninvasive solutions are available for the assessment of patients at risk of deterioration. Capnography, in the form of end-tidal exhaled CO2 (ETCO2) and perfusion index (PI), could provide relevant information about patient prognosis. The aim of the present project was to determine the association of ETCO2 and PI with mortality of patients admitted to the emergency department (ED). METHODS: Multicenter, prospective, cohort study of adult patients with acute disease who needed continuous monitoring in the ED...

The presence of an elevated amount of methane (CH4 ) in exhaled breath can be used as a non-invasive tool to monitor certain health conditions. A compact, inexpensive and transportable CH4 sensor is thus very interesting for this purpose. In addition, if the sensor is also able to simultaneously measure carbon dioxide (CO2 ), one can extract the end-tidal concentration of exhaled CH4 . Here, we report on such a sensor based on a commercial detection module using tunable diode laser absorption spectroscopy. It was found that the measured CH4 /CO2 values exhibit a strong interference with water vapor...

RATIONALE: Understanding mechanisms of drug use decisions will inform the development of treatments for opioid use disorder (OUD). Decision-making experiments using neurobehavioral approaches require many trials or events of interest for statistical analysis, but the pharmacokinetics of most opioids limit dosing in humans. OBJECTIVES: This experiment characterized the effects of repeated infusions of the ultra-short acting opioid remifentanil in people with OUD and physical opioid dependence...

PURPOSE: AirSeal is a valve-less trocar insufflation system which is widely used in robotic urologic surgeries. More evidence is needed concerning the application and cost of AirSeal in retroperitoneal robot-assisted laparoscopic partial nephrectomy. METHODS: We conducted a randomized controlled trial enrolling 62 patients who underwent retroperitoneal robot-assisted laparoscopic partial nephrectomy from February 2022 to February 2023 in the Peking Union Medical College Hospital...

This study aimed to assess the physiological responses to repeated running exercise performed at supramaximal intensity and with end-expiratory breath holding (EEBH) up to the breaking point. Eight male runners participated in two running testing sessions on a motorized treadmill. In the first session, participants performed two sets of 8 repetitions at 125% of maximal aerobic velocity and with maximum EEBH. Each repetition started at the onset of EEBH and ended at its release. In the second session, participants replicated the same procedure, but with unrestricted breathing (URB)...

BACKGROUND: Early recognition of perioperative anaphylaxis, a life-threatening, usually immunoglobulin E [IgE]-mediated, immediate hypersensitivity, is essential, but bedside diagnosis is not always straightforward as clinical presentation may vary. OBJECTIVES: To describe early characteristics of perioperative immediate hypersensitivity (POH), with a special attention on cutaneous phenotypes, and identify risk factors for IgE-mediated allergy. METHODS: We retrospectively analyzed data from adults with suspected POH who were investigated in two academic medical centers...

AIM: Post-resuscitation care is described as the fourth link in a chain of survival in resuscitation guidelines. However, data on prehospital post-resuscitation care is scarce. We aimed to examine the association among systolic blood pressure (SBP), peripheral oxygen saturation (SpO2 ) and end-tidal carbon dioxide (EtCO2 ) after prehospital stabilisation and outcome among patients resuscitated from out-of-hospital cardiac arrest (OHCA). METHODS: In this retrospective study, we evaluated association of the last measured prehospital SBP, SpO2 and EtCO2 before patient handover with 30-day and one-year mortality in 2,611 patients receiving prehospital post-resuscitation care by helicopter emergency medical services in Finland...

INTRODUCTION: The utilization of ultrasonography (USG) is progressively growing to verify the accurate positioning of the endotracheal tube (ETT). Non-detection of the esophageal intubation can be fatal. Various techniques are employed to confirm the placement of the ETT, but none of them are considered optimal. Quantitative waveform capnography (qWC) is often regarded as the most reliable method for this purpose; however, it may not necessarily be accessible and can be expensive. Hence, this investigation was carried out to contrast the use of bedside upper airway USG with qWC in order to confirm the accurate positioning of the ETT following intubation...

BACKGROUND: The control of PaCO2 in ventilated patients is known to be of particular importance in the management and prognosis of trauma patients. Although EtCO2 is often used as a continuous, non-invasive, surrogate marker for PaCO2 in ventilated trauma patients in the emergency department (ED), previous studies suggest a poor correlation in this cohort. However, previous data has predominantly been collected retrospectively, raising the possibility that the elapsed time between PaCO2 sampling and EtCO2 recording may contribute to the poor correlation...

BACKGROUND: Fiberoptic intubation (FOI) is considered a beneficial modality used to intubate life-threatening airway patients. This study aims at assessing the effectiveness of shortened uncuffed endotracheal tube as a nasopharyngeal airway during FOI. METHODS: Between January 2019 and March 2021, this prospective randomized controlled trial has enrolled 62 adult patients (56 males and 6 females) with normal airways scheduled for elective oral FOI classified American Society of Anesthesiologists (ASA I-III), their age ranged 20-60 years...

BACKGROUND: Mediastinoscopic surgery for esophageal cancer facilitates early postoperative recovery. However, it can occasionally cause serious complications. Here, we present the case of a patient with a tracheal injury diagnosed by a sudden increase in end-tidal carbon dioxide (EtCO2 ) during mediastinoscopic subtotal esophagectomy. CASE PRESENTATION: A 52-year-old man diagnosed with esophageal cancer was scheduled to undergo mediastinoscopic subtotal esophagectomy...

INTRODUCTION: Various scoring systems have been developed to safely rule out the diagnosis of acute coronary syndrome. Furthermore, the efficacy of these scoring systems in predicting the risk of major adverse cardiac events (MACE) is debated. Our aim was to compare parameters such as Integrated Pulmonary Index (IPI) and End Tidal Carbon Dioxide (etCO2) measured in the emergency department with the HEART score in terms of its success in predicting the risk of major adverse cardiac events...

INTRODUCTION: Breath-holding preceded by either an overnight fast or hyperventilation have been shown to potentiate the risk of a hypoxic blackout. However, no study has explored the combined effects of fasting and hyperventilation on apneic performance and associated physiological responses. METHODS: Nine, non-divers (8 males) attended the laboratory on two separate occasions (≥48-h apart), both after a 12-h overnight fast. During each visit a hyperoxic rebreathing trial was performed followed by three repeated maximal static apneas preceded by either normal breathing (NORM) or a 30s hyperventilation (HYPER)...

BACKGROUND: The aim of this study was to analyze cold stimulation-induced changes in cerebral and cardiac hemodynamics. METHODS: Upon ingestion of an ice cube, the changes in resistance index, mean flow velocity and flow index of the middle cerebral arteries (MCA) were assessed using transcranial Doppler sonography. Extracranial duplex sonography was used to measure the mean flow velocity and resistance index of the right internal carotid artery (ICA). The change in mean arterial pressure, heart rate, root mean square of successive differences (RMSSD) and end-tidal carbon dioxide pressure were analyzed additionally...

BACKGROUND: Low-normal levels of arterial carbon dioxide (PaCO2) are recommended in the acute phase of traumatic brain injury (TBI) to optimize oxygen and CO2 tension, and to maintain cerebral perfusion. End-tidal CO2 (ETCO2) may be used as a surrogate for PaCO2 when arterial sampling is less readily available. ETCO2 may not be an adequate proxy to guide ventilation and the effects on concomitant injury, time, and the impact of ventilatory strategies on the PaCO2-ETCO2 gradient are not well understood...

BACKGROUND: In critically ill patients, especially those with septic shock, fluid management can be a challenging aspect of clinical care. One of the primary steps in treating patients with hemodynamic instability is optimizing intravascular volume. The Passive Leg Raising (PLR) maneuver is a reliable test for assessing fluid responsiveness, as demonstrated by numerous studies and meta-analyses. However, its use requires the measurement of cardiac output, which is often complex and may necessitate clinician experience and specialized equipment...

OBJECTIVES: To examine if increasing blood pressure improves brain tissue oxygenation (PbtO2) in adults with severe traumatic brain injury (TBI). DESIGN: Retrospective review of prospectively collected data. SETTING: Level-I trauma center teaching hospital. PATIENTS: Included patients greater than or equal to 18 years of age and with severe (admission Glasgow Coma Scale [GCS] score < 9) TBI who had advanced neuromonitoring (intracranial blood pressure [ICP], PbtO2, and cerebral autoregulation testing)...