Prehospital emergency care is the primary stage in the treatment of critically ill patients, where efficient and accurate monitoring methods are crucial for patient survival and prognosis. End-tidal carbon dioxide (EtCO₂) monitoring is a real-time, non-invasive method that can sensitively capture the status of respiratory, circulatory, and metabolic functions, particularly in the urgent and complex pre-hospital environment, a immediate detection and non-invasive method, can sensitively capture the respiratory, circulatory, and metabolic status of patients. It provides valuable guidance for rapid decision-making and precise interventions. This is particularly valuable in the complex and urgent prehospital environment, providing critical data for rapid decision-making and precise intervention. This paper systematically reviews the advancements in the application of EtCO₂ monitoring across various fields, including sepsis identification, trauma assessment, cardiac arrest, respiratory critical care, endotracheal intubation confirmation, and management of metabolic diseases, aiming to explore its application value and prospects in pre-hospital emergency care.
Humans ; Emergency Medical Services/methods* ; Carbon Dioxide/analysis* ; Monitoring, Physiologic/methods* ; Critical Illness ; Capnography/methods*

With the rapid development of diagnostic and therapeutic procedures performed outside the operating room (OR), the need for appropriate sedation care has emerged in importance to ensure the safety and comfort of patients and clinicians. The preparation and administration of sedatives and sedation care outside the OR require careful attention, proper monitoring systems, and clinically useful sedation guidelines. This literature review addresses proper monitoring and selection of sedatives for diagnostic and interventional procedures outside the OR. As the depth of sedation increases, respiratory depression and cardiovascular suppression become serious, necessitating careful surveillance using appropriate monitoring equipment.
Capnography ; Dexmedetomidine ; Humans ; Hypnotics and Sedatives ; Operating Rooms ; Respiratory Insufficiency

BACKGROUND: Respiration monitoring is necessary during sedation for dental treatment. Recently, acoustic respiration rate (RRa™), an acoustics-based respiration monitoring method, has been used in addition to auscultation or capnography. The accuracy of this method may be compromised in an environment with excessive noise. This study evaluated whether noise from the ultrasonic scaler affects the performance of RRa in respiratory rate measurement. METHODS: We analyzed data from 49 volunteers who underwent scaling under intravenous sedation. Clinical tests were divided into preparation, sedation, and scaling periods; respiratory rate was measured at 2-s intervals for 3 min in each period. Missing values ratios of the RRa during each period were measuerd; correlation analysis and Bland-Altman analysis were performed on respiratory rates measured by RRa and capnogram. RESULTS: Respective missing values ratio from RRa were 5.62%, 8.03%, and 23.95% in the preparation, sedation, and scaling periods, indicating an increased missing values ratio in the scaling period (P < 0.001). Correlation coefficients of the respiratory rate, measured with two different methods, were 0.692, 0.677, and 0.562 in each respective period. Mean capnography-RRa biases in Bland-Altman analyses were −0.03, −0.27, and −0.61 in each respective period (P < 0.001); limits of agreement were −4.84–4.45, −4.89–4.15, and −6.18–4.95 (P < 0.001). CONCLUSIONS: The probability of missing respiratory rate values was higher during scaling when RRa was used for measurement. Therefore, the use of RRa alone for respiration monitoring during ultrasonic scaling may not be safe.
Acoustics ; Auscultation ; Bias (Epidemiology) ; Capnography ; Dental Scaling ; Methods ; Noise ; Respiration ; Respiratory Rate ; Ultrasonics ; Volunteers

No abstract available.
Capnography* ; Humans

No abstract available.
Capnography ; Humans

PURPOSE: Recently, the use of end-tidal carbon dioxide (ETCO₂) monitoring has been suggested for early detection of hypoventilation over oxygen saturation (S(P)O₂) monitoring. We aimed to determine the usefulness of capnography in monitoring patients sedated using intramuscular (IM) ketamine in the pediatric emergency department (ED). METHODS: This study retrospectively reviewed medical records of patients younger than 16 years who were sedated using IM ketamine and whose ETCO₂ values were documented in the ED. Age, sex, American Society of Anesthesiologists physical status classification (ASA classification), and purpose of sedation were investigated. Vital signs were recorded at pre-sedation, 5 and 10 minutes after sedation, and after recovery. Hypoventilation was defined as S(P)O₂< 95%, ETCO₂≥ 50 mmHg or ≤ 30 mmHg, or increase in ETCO₂≥ 10 mmHg from the baseline without tachypnea. RESULTS: A total of 49 patients were investigated; 42 of them belonged to ASA classification I, and 7 to II. There was no patient with S(P)O₂< 95%, or ETCO₂≥ 50 mmHg, or increase in ETCO₂≥ 10 mmHg from the pre-sedation value. However, 5 patients had an ETCO₂≤ 30 mmHg, and 4 of them (8.2%) had normal respiratory rate and were suitable for hypopneic hypoventilation. Ten patients showed abnormal range of ETCO₂ (normal range, 35-45 mmHg), but did not meet the definition of hypoventilation. No one had clinically serious respiratory events. CONCLUSIONS: During sedation using IM ketamine, 8.2% of the patients had hypopneic hypoventilation without hypoxemia, and they were all younger than 36 months. Capnography for patients sedated using IM ketamine in the ED is useful in detecting hypopneic hypoventilation, and has the potential for preventing clinically serious respiratory events in patients, especially toddlers.
Anoxia ; Capnography ; Carbon Dioxide* ; Carbon* ; Classification ; Conscious Sedation ; Emergencies* ; Emergency Service, Hospital* ; Humans ; Hypoventilation ; Ketamine* ; Medical Records ; Oxygen ; Pediatrics ; Respiratory Rate ; Retrospective Studies ; Tachypnea ; Vital Signs

PURPOSEThis prospective observational study aims to evaluate the accuracy of dead-space fraction derived from the ventilator volumetric capnography (volumetric CO₂) or a prediction equation to predict the survival of mechanically ventilated patients with acute respiratory distress syndrome (ARDS).

METHODSConsecutive VD/VT measurements were obtained based upon a prediction equation validated by Frankenfield et al for dead-space ventilation fraction: VD/VT = 0.320 + 0.0106 (PaCO₂-ETCO₂)⁺ 0.003 (RR)⁺0.0015 (age) in adult patients who had infection-related severe pneumonia and were confirmed as having ARDS. Here PaCO₂ is the arterial partial pressure of carbon dioxide in mmHg; ETCO₂, the end- tidal carbon dioxide measurement in mmHg; RR, respiratory rate per minute; and age in years. Once the patient had intubation, positive end expiratory pressure was adjusted and after Phigh reached a steady state, VD/VT was measured and recorded as the data for the first day. VD/VT measurement was repeated on days 2, 3, 4, 5 and 6. Meanwhile we collected dead-space fraction directly from the ventilator volu- metric CO₂ and recorded it as Vd/Vt. We analyzed the changes in VD/VT and Vd/Vt over the 6-day period to determine their accuracy in predicting the survival of ARDS patients.

RESULTSOverall, 46 patients with ARDS met the inclusion criteria and 24 of them died. During the first 6 days of intubation, VD/VT was significantly higher in nonsurvivors on day 4 (0.70 ± 0.01 vs 0.57 ± 0.01), day 5 (0.73 ± 0.01 vs. 0.54 ± 0.01), and day 6 (0.73 ± 0.02 vs. 0.54 ± 0.01) (all p =0.000). Vd/Vt showed no significant difference on days 1e4 but it was much higher in nonsurvivors on day 5 (0.45 ± 0.04 vs. 0.41 ± 0.06) and day 6 (0.47 ± 0.05 vs. 0.40 ± 0.03) (both p=0.008). VD/VT on the fourth day was more accurate to predict survival than Vd/Vt. The area under the receiver-operating characteristic curve for VD/VT and Vd/Vt in evaluating ARDS patients survival was day 4 (0.974 ± 0.093 vs. 0.701 ± 0.023, p = 0.0024) with the 95% confidence interval being 0.857-0.999 vs. 0.525-0.841.

CONCLUSIONCompared with Vd/Vt derived from ventilator volumetric CO₂, VD/VT on day 4 calculated by Frankenfield et al's equation can more accurately predict the survival of ARDS patients.

Adult ; Capnography ; Female ; Humans ; Male ; Middle Aged ; Prospective Studies ; ROC Curve ; Respiration, Artificial ; Respiratory Dead Space ; physiology ; Respiratory Distress Syndrome, Adult ; mortality ; physiopathology

BACKGROUND: The apnea test (AT) is essential to confirming the diagnosis of brain death, but critical complications can occur if the AT is maintained over a long period. To minimize the AT period, we used end-tidal carbon dioxide (ETCO2) monitoring because ETCO2 is closely correlated with partial pressure of arterial carbon dioxide (PaCO2). The aim of the present study is to evaluate the usefulness of ETCO2 monitoring during apnea testing. METHODS: We reviewed 61 patients who were pronounced brain dead at our hospital from July 2009 to December 2012. The subjects were divided into two groups: the N-group, in which capnography was not used, and the C-group, in which capnography was used to monitor ETCO2. In the C-group, whenever arterial blood was sampled, the PaCO2 - ETCO2 gradients were calculated and the ventilator setting adjusted to maintain normocapnia prior to apnea testing. RESULTS: Twenty-eight subjects in the N-group and twenty-nine subjects in the C-group were included. The gender ratio, age, and cause of brain death were not different between the two groups. Prior to the AT, the normocapnia ratio was higher in the C-group than in the N-group. During the AT, the total test period was shorter in the C-group. Moreover, systolic blood pressure increased in the C-group and decreased in the N-group during apnea testing. CONCLUSIONS: ETCO2 monitoring during AT allows the PaCO2 level to be predicted, which reduces the duration of the test and stabilizes systolic blood pressure. Thus, with ETCO2 monitoring, the AT can be fast and safe.
Apnea* ; Blood Gas Analysis ; Blood Pressure ; Brain Death ; Capnography ; Carbon Dioxide* ; Diagnosis ; Humans ; Partial Pressure ; Ventilators, Mechanical

Malfunction of the unidirectional valve in a breathing circuit system may cause hypercapnia from the rebreathing of expired gas, ventilation failure, and barotrauma. Capnography is a useful method for monitoring the integrity of the unidirectional valve. We experienced two cases of malfunction of a unidirectional valve which caused leakage and reverse flow, diagnosed early as a change of the capnographic waveform. One case was caused by expiratory unidirectional valve breakage. The other was caused by an incorrectly-assembled inspiratory unidirectional valve.
Barotrauma ; Capnography ; Hypercapnia ; Respiration ; Ventilation

The demand for sedation outside of the operating room for diagnostic or therapeutic procedures has recently been dramatically increasing. The Joint Commission International (JCI) is pressing domestic hospitals trying to obtain JCI certification to accept its sedation policies. This article aimed to investigate recent trends in sedation and suggest desirable directions for safe and high-quality sedation. The most active areas in research are procedural sedation, sedation in the intensive care unit (ICU), and pediatric sedation. Patient safety and performance of procedures without complications are the most important goals during sedation. According to the JCI regulation, noninvasive blood pressure, electrocardiography, pulse oximetry and capnography are the basic requirements, and sedation personnel should be separate from those who perform the procedure. Careful preprocedural assessment and tight intra-procedural monitoring for airway obstruction are critical in procedural sedation. Many merits of dexmedetomidine in procedural sedation have been reported despite its hemodynamic risks. Daily intermittent interruption is the main trend in ICU sedation providing better outcomes for mechanically ventilated patients. Analgosedation in the ICU is initial analgesia starting with remifentanil and later adding sedatives if required. Individual readjustment of the dosage using a sedation scoring system is a key requirement for successful results in ICU sedation. Ketofol, mixture of ketamine and propofol, has recently become popular for painful pediatric procedures. Pediatric sedation (especially for those < or = 3 years) with computed tomography or magnetic resonance imaging examination has a greater risk of hypoxia, but pediatric sedation experts are lacking. In conclusion, there is an urgent need for the nationwide establishment of standard sedation regulation, and securing or training sedation specialists.
Airway Obstruction ; Ambulatory Surgical Procedures ; Analgesia ; Anoxia ; Blood Pressure ; Capnography ; Certification ; Dexmedetomidine ; Electrocardiography ; Hemodynamics ; Humans ; Hypnotics and Sedatives ; Intensive Care Units ; Joints ; Ketamine ; Magnetic Resonance Imaging ; Operating Rooms ; Oximetry ; Patient Safety ; Piperidines ; Propofol ; Specialization