End-tidal Carbon Dioxide (end-tidal + carbon_dioxide)

Distribution by Scientific Domains


Selected Abstracts


Emergency Physician,Verified Out-of-hospital Intubation: Miss Rates by Paramedics

ACADEMIC EMERGENCY MEDICINE, Issue 6 2004
James H. Jones MD
Abstract Objectives: To prospectively quantify the number of unrecognized missed out-of-hospital intubations by ground paramedics using emergency physician verification as the criterion standard for verification of endotracheal tube placement. Methods:The authors performed an observational, prospective study of consecutive intubated patients arriving by ground emergency medical services to two urban teaching hospitals. Endotracheal tube placement was verified by emergency physicians and evaluated by using a combination of direct visualization, esophageal detector device (EDD), colorimetric end-tidal carbon dioxide (ETCO2), and physical examination. Results: During the six-month study period, 208 out-of-hospital intubations by ground paramedics were enrolled, which included 160 (76.9%) medical patients and 48 (23.1%) trauma patients. A total of 12 (5.8%) endotracheal tubes were incorrectly placed outside the trachea. This comprised ten (6.3%) medical patients and two (4.2%) trauma patients. Of the 12 misplaced endotracheal tubes, a verification device (ETCO2 or EDD) was used in three cases (25%) and not used in nine cases (75%). Conclusions: The rate of unrecognized, misplaced out-of-hospital intubations in this urban, midwestern setting was 5.8%. This is more consistent with results of prior out-of-hospital studies that used field verification and is discordant with the only other study to exclusively use emergency physician verification performed on arrival to the emergency department. [source]


Bispectral Electroencephalographic Analysis of Patients Undergoing Procedural Sedation in the Emergency Department

ACADEMIC EMERGENCY MEDICINE, Issue 6 2003
James R. Miner MD
Abstract Objective: To determine whether there is a correlation between the level of sedation achieved during procedural sedation (PS) in the emergency department as determined by bispectral electroencephalographic (EEG) analysis (BIS) and the rate of respiratory depression (RD), the patient's perception of pain, recall of the procedure, and satisfaction. Methods: This was a prospective observational study conducted in an urban county hospital of adult patients undergoing PS using propofol, methohexital, etomidate, and the combination of fentanyl and midazolam. Consenting patients were monitored by vital signs, pulse oximetry, nasal-sample end-tidal carbon dioxide (ETCO2), and BIS monitors during PS. Respiratory depression (RD) was defined as an oxygen saturation <90%, a change from baseline ETCO2 of >10 mm Hg, or an absent ETCO2 waveform at any time during the procedure. After the procedure, patients were asked to complete three 100-mm visual analog scales (VASs) concerning their perception of pain, recall of the procedure, and satisfaction with the procedure. Patients were divided into four groups based on the lowest BIS score recorded during the procedure, group 1, >85; group 2, 70,85; group 3, 60,69; group 4, <60. Rates of RD and VAS outcomes were compared between groups using chi-square statistics. Results: One hundred eight patients were enrolled in the study. No serious adverse events were noted. RD was seen in three of 14 (21.4%) of the patients in group 1, seven of 34 (20.6%) in group 2, 16 of 26 (61.5%) in group 3, and 18 of 34 (52.9%) in group 4. The rate of RD in patients in group 2 was not significantly different from that in group 1 (p = 0.46). The rate of RD in group 2 was significantly lower than that in groups 3 (p = 0.0003) and 4 (p = 0.006). For the VAS data, when group 1 was compared with the combined groups 2, 3, and 4, it had significantly higher rates of pain (p = 0.003) and recall (p = 0.001), and a dissatisfaction rate (p = 0.085) that approached significance. When groups 2, 3, and 4 were compared with chi-square test, there was not a significant difference in pain (p = 0.151), recall (p = 0.27), or satisfaction (p = 0.25). Conclusions: Patients with a lowest recorded BIS score between 70 and 85 had the same VAS outcomes as more deeply sedated patients and the same rate of RD as less deeply sedated patients. This range of scores represented the optimally sedated patients in this study. [source]


Haemodynamic changes during positive-pressure ventilation in children

ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 5 2005
A. Kardos
Background:, Positive-pressure ventilation may alter cardiac function. Our objective was to determine with the use of impedance cardiography (ICG) whether altering airway pressure modifies the central haemodynamics in mechanically ventilated children with no pulmonary pathology. Central venous saturation (ScvO2) was measured as an indicator of tissue perfusion. Methods:, Twelve children between 7 and 65 months of age, requiring mechanical ventilation as a consequence of a non-pulmonary disease, were enrolled in the study. All patients had a central venous line as a part of their routine management. Using pressure controlled ventilation (PCV) the baseline PEEP value of 5 cmH2O (Pb5) was increased to 10 cmH2O (Pi10) and then to 15 cmH2O (Pi15). After Pi15, PEEP was decreased to 10 (Pd10) and then to 5 cmH2O (Pd5). Each time period lasted 5 min heart rate (HR), mean arterial blood pressure (MABP), central venous pressure (CVP), end-tidal carbon dioxide (ETCO2), mean airway pressure (Paw), stroke volume index (SVI), cardiac index (CI) and central venous oxygen saturation (ScvO2) were recorded at the end of the five periods. Results:, The values of CI did not change when 10 and 15 cmH2O of PEEP were applied. Elevation of PEEP and thus Paw caused slight but not significant reductions in SVI and ScvO2 as compared to the baseline (Tb5). After reducing PEEP in Td5 we found statistically significant elevations of SVI and CI, as compared to Ti15 heart rate, ETCO2 and MABP remained unchanged. Conclusion:, We did not find significant haemodynamic changes following PEEP elevation in ventilated children, as measured using impedance cardiography. Reducing the value of PEEP to 5 cmH2O resulted in statistically significant SVI elevations. The values of ScvO2 remained unaffected. [source]


Dynamic cerebral autoregulation in healthy adolescents

ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 4 2002
M. S. Vavilala
Background: There is little information on the limits of cerebral autoregulation and the autoregulatory capacity in children. The aim of this study was to compare dynamic cerebral autoregulation between healthy adolescents and adults. Methods: Seventeen healthy volunteers 12,17 years (n = 8) and 25,45 years (n = 9) were enrolled in this study. Bilateral mean middle cerebral artery flow velocities (Vmca; (cm/s)) were measured using transcranial Doppler ultrasonography (TCD). Mean arterial blood pressure (MAP) and end-tidal carbon dioxide were measured continuously during dynamic cerebral autoregulation studies. Blood pressure cuffs were placed around both thighs and inflated to 30 mmHg above the systolic blood pressure for 3 min and then rapidly deflated, resulting in transient systemic hypotension. The change of Vmca to change in MAP constitutes the autoregulatory response, and the speed of this response was quantified using computer model parameter estimation. The dynamic autoregulatory index (ARI) was averaged between the two sides. Results: Adolescents had significantly lower ARI (3.9 ± 2.1 vs. 5.3 ± 0.8; P=0.05), and higher Vmca (75.2 ± 15.2 vs. 57.6 ± 15.0; P<0.001) than adults. Conclusion: The autoregulatory index is physiologically lower in normal adolescents 12,17 years of age than in adults. [source]


The Use of Cerebral Oximetry as a Monitor of the Adequacy of Cerebral Perfusion in a Patient Undergoing Shoulder Surgery in the Beach Chair Position

PAIN PRACTICE, Issue 4 2009
Gregory W. Fischer MD
Abstract Four cases of ischemic injury have been reported in patients undergoing orthopedic surgery in the upright position. We describe the use of cerebral oximetry as a monitor of the adequacy of cerebral perfusion in a 63-year-old woman who underwent arthroscopic rotator cuff surgery in a beach chair under general anesthesia. During positioning, a decrease in blood pressure was accompanied by a decrease in cerebral oxygen saturation (SctO2) and was treated with phenylephrine. When spontaneous ventilation resumed, an increase in end-tidal carbon dioxide was accompanied by an increase in SctO2. Cerebral oximetry may prove useful as a guide monitor and manage nonsupine patients. [source]


Continuous non-invasive end-tidal CO2 monitoring in pediatric inpatients with diabetic ketoacidosis

PEDIATRIC DIABETES, Issue 4 2006
Michael SD Agus
Introduction:, Pediatric inpatients with diabetic ketoacidosis (DKA) are routinely subjected to frequent blood draws in order to closely monitor degree of acidosis and response to therapy. The typical level of acidosis monitoring is less than ideal, however, because of the high cost and invasiveness of frequent blood labs. Previous studies have validated end-tidal carbon dioxide (EtCO2) monitoring in the emergency department (ED) for varying periods of time. We extend these findings to the inpatient portion of the hospitalization during which the majority of blood tests are sent. Methods:, All patients admitted to an intermediate care unit in (InCU) a large children's hospital were fitted with an appropriately sized oral/nasal cannula capable of sensing EtCO2. Laboratory studies were obtained according to hospital clinical practice guidelines. In a retrospective analysis, EtCO2 values were correlated with serum total CO2 (stCO2), venous pH (vpH), venous pCO2 (vpCO2), and calculated bicarbonate from venous blood gas (vHCO3,). Results:, A total of 78 consecutive episodes of DKA in 72 patients aged 1,21 yr were monitored for 3,38 h with both capnography and laboratory testing, producing 334 comparisons. Initial values were as follows, reported as median (range): stCO2, 11 (4,22) mmol/L; vpH, 7.281 (6.998,7.441); vpCO2, 28.85 (9.3,43.3) mmHg; and vHCO3,, 14 (3,25) mmol/L. EtCO2 was correlated well with stCO2 (r = 0.84, p < 0.001), vHCO3, (r = 0.84, p < 0.001), and vpCO2 (r = 0.79, p < 0.001). Conclusions:, These data support the findings of previous studies limited to ED populations and suggest that non-invasive EtCO2 monitoring is a valuable and reliable tool to continuously follow acidosis in the setting of the acutely ill pediatric patient with DKA. Continuous EtCO2 monitoring offers the practitioner an early warning system for unexpected changes in acidosis that augments the utility of intermittent blood gas determinations. [source]


Evaluation of a transportable capnometer for monitoring end-tidal carbon dioxide

ANAESTHESIA, Issue 10 2010
T. Hildebrandt
Summary We compared a small and transportable Capnometer (EMMAÔ) with a reference capnometer, the Siesta i TS Anaesthesia. During air-breathing through a facemask, both the EMMA (nine modules) and reference capnometer sampled expired gas simultaneously. A wide range of end-tidal carbon dioxide values were obtained during inhalation of carbon dioxide and voluntary hyperventilation. The median IQR [range] difference between all sets of carbon dioxide values (EMMA , reference) was ,0.3 (,0.6 to 0.0 [,1.7 to 1.6] kPa; n = 297) using new batteries, which was statistically significant (p = 0.04) and located to two of the nine EMMAs tested. Using batteries with reduced voltage did not influence the measurements. The 95% CI of the medians of the differences were ,0.4 to ,0.2. We conclude that the EMMA can slightly under-read the end-tidal carbon dioxide but is generally comparable with a free-standing monitor. The precision of the EMMAs was similar whether new batteries or batteries with reduced voltage were used. [source]


A comparison of the i-gelÔ with the LMA-UniqueÔ in non-paralysed anaesthetised adult patients

ANAESTHESIA, Issue 10 2009
H. Francksen
Summary This study assessed two disposable devices; the newly developed supraglottic airway device i-gelÔ and the LMA-UniqueÔ in routine clinical practice. Eighty patients (ASA 1,3) undergoing minor routine gynaecologic surgery were randomly allocated to have an i-gel (n = 40) or LMA-Unique (n = 40) inserted. Oxygen saturation, end-tidal carbon dioxide, tidal volume and peak airway pressure were recorded, as well as time of insertion, airway leak pressure, postoperative sore-throat, dysphonia and dysphagia for each device. Time of insertion was comparable with the i-gel and LMA-Unique. There was no failure in the i-gel group and one failure in the LMA-Unique group. Ventilation and oxygenation were similar between devices. Mean airway pressure was comparable with both devices, whereas airway leak pressure was significantly higher (p < 0.0001) in the i-gel group (mean 29 cmH2O, range 24,40) compared with the LMA-Unique group (mean 18 cmH2O, range 6,30). Fibreoptic score of the position of the devices was significantly better in the i-gel group. Post-operative sore-throat and dysphagia were comparable with both devices. Both devices appeared to be simple alternatives to secure the airway. Significantly higher airway leak pressure suggests that the i-gel may be advantageous in this respect. [source]


End-tidal Carbon Dioxide Measurements in Children with Acute Asthma

ACADEMIC EMERGENCY MEDICINE, Issue 12 2007
Bridgette D. Guthrie MD
Objectives A noninvasive method to assess ventilation may aid in management of children with acute asthma. The purpose of this study was to evaluate the association between end-tidal carbon dioxide (EtCO2) values and disease severity among children with acute asthma. Methods This was a prospective, blinded, observational study of children 3,17 years old treated for acute asthma in a pediatric emergency department (ED). EtCO2 measurements were taken before the initiation of therapy and after each nebulization treatment (maximum of three). Peak expiratory flow rate (PEFR), Pediatric Asthma Severity Score (PASS), oxygen saturation, and disposition were recorded. Treating physicians, unaware of the EtCO2 results, made all treatment decisions, including disposition. Results One hundred children were enrolled. The mean initial EtCO2 value was 35 mm Hg (95% confidence interval = 34.3 to 36.1 mm Hg). The mean disposition EtCO2 value was 33.3 mm Hg (95% confidence interval = 32.6 to 34.4 mm Hg). PEFR measures were completed on 43 patients and PASS recorded on 100 patients. There was an overall trend toward lower EtCO2 values during treatment (p < 0.01). Sixteen patients were admitted. Initial EtCO2 values were lower among children admitted to the hospital (35.6 mm Hg vs. 32.9 mm Hg; Mann-Whitney U test; p < 0.02). EtCO2 values at disposition did not differ between groups based on PEFR, PASS, or hospital admission. Conclusions Noninvasive bedside measurement of EtCO2 values among children with acute asthma is feasible. EtCO2 values did not distinguish children with mild disease from those with more severe disease. Further data are needed to clarify the association between EtCO2 values and other indicators of disease severity, particularly in children with more severe disease. [source]


Increased Cerebral Blood Flow And Cardiac Output Following Cerebral Arterial Air Embolism In Sheep

CLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 11 2001
David J Williams
SUMMARY 1. The effects of cerebral arterial gas embolism on cerebral blood flow and systemic cardiovascular parameters were assessed in anaesthetized sheep. 2. Six sheep received a 2.5 mL injection of air simultaneously into each common carotid artery over 5 s. Mean arterial blood pressure, heart rate, end-tidal carbon dioxide and an ultrasonic Doppler index of cerebral blood flow were monitored continuously. Cardiac output was determined by periodic thermodilution. 3. Intracarotid injection of air produced an immediate drop in mean cerebral blood flow. This drop was transient and mean cerebral blood flow subsequently increased to 151% before declining slowly to baseline. Coincident with the increased cerebral blood flow was a sustained increase in mean cardiac output to 161% of baseline. Mean arterial blood pressure, heart rate and end-tidal carbon dioxide were not significantly altered by the intracarotid injection of air. 4. The increased cardiac output is a pathological response to impact of arterial air bubbles on the brain, possibly the brainstem. The increased cerebral blood flow is probably the result of the increased cardiac output and dilation of cerebral resistance vessels caused by the passage of air bubbles. [source]