OBJECTIVES: To evaluate the accuracy and safety of measurements of transcutaneous carbon dioxide partial pressure (TcPCO METHODS: A total of 45 very low birth weight infants were enrolled. TcPCO RESULTS: There was no significant difference in TcPCO CONCLUSIONS Lower electrode temperatures (38-41℃) can accurately measure blood carbon dioxide partial pressure in very low birth weight infants, and thus can be used to replace the electrode temperature of 42°C. Transcutaneous measurements at the lower electrode temperatures may be helpful for understanding the changing trend of blood oxygen partial pressure.
Blood Gas Monitoring, Transcutaneous ; Carbon Dioxide ; Electrodes ; Humans ; Infant ; Infant, Newborn ; Infant, Very Low Birth Weight ; Oxygen ; Partial Pressure ; Temperature

carbon dioxide, pressure of oxygen, total carbon dioxide, bicarbonate, base excess, oxygen saturation, and lactate), the CG6+ cartridge (for sodium, potassium, chloride, blood glucose, blood urea nitrogen, hematocrit, and hemoglobin), and enzyme-linked immunosorbent assay kits (calcium, magnesium, creatinine, aspartate aminotransferase, alanine aminotransferase, bilirubin, and albumin). Similar trends were found for the parameters of biochemistries, electrolytes, and blood gas, and they revealed no significant changes after blood withdrawal-induced hemorrhagic shock. However, the TBS group showed more effective ability to correct metabolic acidosis than the NS and RS groups. TBS was a feasible and safe resuscitation solution in this study and may be an alternative to NS and RS for resuscitation in hemorrhagic shock patients without liver damage.]]>
Acidosis ; Alanine Transaminase ; Animals ; Aspartate Aminotransferases ; Bilirubin ; Blood Glucose ; Blood Urea Nitrogen ; Carbon Dioxide ; Creatinine ; Electrolytes ; Enzyme-Linked Immunosorbent Assay ; Hematocrit ; Hemodynamics ; Humans ; Hydrogen-Ion Concentration ; Liver ; Magnesium ; Male ; Oxygen ; Potassium ; Rats ; Resuscitation ; Shock, Hemorrhagic ; Sodium

OBJECTIVE: Stroke volume (SV) measurements have been used to guide fluid management. Noninvasive, indirect, and convenient measurements of the SV for fluid therapy are required for most patients during spontaneous breathing (SB). On the other hand, the preferred method for an indirect prediction of the SV is unclear. This study examined the best of the indirect and predictable parameters responding to a SV variation during SB. METHODS: Hemodynamic parameters, such as collapsibility of the inferior vena cava (cIVC), peak velocity variation in the common carotid artery (pvvCCA), collapsibility of the internal jugular vein (cIJV), and end-tidal carbon dioxide (ETCO₂) were measured 180 times (6 different positions each in 30 normal subjects). The variables changed with the SV at the upper body elevation of 60°and 30°, in the supine position, at the lower body elevation of 60°and 30°, and lumbar elevation. RESULTS: The SV showed the highest value at 30°of lower body elevation. Following fixed position changes, the ETCO₂ during SB was the factor most correlated with the SV when compared to cIVC, cIJV, and pvvCCA (β coefficient, 2.432 vs. −0.41, −0.033, and −0.654; P=0.004). The adjusted ETCO₂ showed a significant change with the SV, even though the change in ETCO₂ was not large. CONCLUSION: ETCO₂ was less influenced by the SB than cIVC, pvvCCA, and cIJV because the ETCO₂ change was in accordance but the variations of the other blood vessels did not coincide with a SV change. Therefore, ETCO₂ monitoring for predicting the SV would be more important than the variations in the vessels during SB.
Blood Vessels ; Carbon Dioxide ; Carbon ; Cardiac Output ; Carotid Artery, Common ; Fluid Therapy ; Hand ; Hemodynamics ; Humans ; Jugular Veins ; Methods ; Respiration ; Stroke Volume ; Stroke ; Supine Position ; Ultrasonography ; Vena Cava, Inferior

OBJECTIVE: To evaluate the prognostic value of the difference between peripheral venous and arterial partial pressure of carbon dioxide in patients with septic shock following early resuscitation. METHODS: This prospective study was conducted among the patients with septic shock treated in our department during the period from May, 2017 to May, 2018. Peripheral venous, peripheral arterial and central venous blood samples were collected simultaneously and analyzed immediately at bedside after 6-h bundle treatment. Arterial blood lactate concentration (Lac) and the arterial (PaCO), peripheral venous (PpvCO) and central venous partial pressure of carbon dioxide (PcvCO) were recorded. The differences between PpvCO and PaCO (Ppv-aCO) and between PcvCO and PaCO (Pcv-aCO) were calculated. Pearson correlation analysis was used to test the agreement between Pcv-aCO and Ppv-aCO. Multivariable logistic regression analysis was performed to analyze the possible risk factors for 28-day mortality, and the receiver-operating characteristic curve (ROC) was plotted to assess the prognostic values of these factors for 28-day mortality. RESULTS: A total of 62 patients were enrolled in this study, among who 35 survived and 27 died during the 28-day period. Compared with the survivor group, the patients died within 28 days showed significantly higher Acute Physiology and Chronic Health Evaluation Ⅱ (APACHE Ⅱ) score (24.2±6.0 20.5±4.9, =0.011), sequential organ failure assessment (SOFA) score (14.9±4.7 12.2±4.5, =0.027), PcvaCO (5.5±1.6 7.1±1.7, < 0.001), PpvaCO (7.1±1.8 10.0±2.7, < 0.001), and arterial lactate level (3.3±1.2 4.2±1.3, =0.003) after 6-h bundle treatment. Pearson correlation analysis showed that Ppv-aCO was significantly correlated with Pcv-aCO (=0.897, R= 0.805, < 0.001). Multiple logistic regression analysis identified Ppv-aCO (β=0.625, =0.001, OR=1.869, 95% CI: 1.311-2.664) and lactate level (β=0.584, =0.041, OR=1.794, 95%CI: 1.024-3.415) as the independent risk factors for 28-day mortality. The maximum area under the ROC (AUC) of Ppv-aCO was 0.814 (95%CI: 0.696- 0.931, < 0.001), and at the best cut- off value of 9.05 mmHg, Ppv-aCO had a sensitivity of 70.4% and a specificity of 88.6% for predicting 28-day mortality. The AUC of lactate level was 0.732 (95%CI: 0.607-0.858, =0.002), and its sensitivity for predicting 28-day mortality was 70.4% and the specificity was 74.3% at the best cut-off value of 3.45 mmol/L; The AUC of Pcv-aCO was 0.766 (95%CI: 0.642-0.891, < 0.001), and its sensitivity was 66.7% and the specificity was 80.0% at the best cut-off value of 7.05 mmHg. CONCLUSIONS A high Ppv-aCO after early resuscitation of septic shock is associated with poor outcomes. Ppv-aCO is well correlated with Pcv-aCO and can be used as an independent indicator for predicting 28-day mortality in patients with septic shock.
APACHE ; Carbon Dioxide ; Cardiopulmonary Resuscitation ; Humans ; Lactic Acid ; blood ; Organ Dysfunction Scores ; Partial Pressure ; Pilot Projects ; Prognosis ; Prospective Studies ; ROC Curve ; Regression Analysis ; Shock, Septic ; blood ; mortality

PURPOSE: Removal of CO₂ is much efficient during high-frequency oscillatory ventilation (HFOV) for preterm infants. However, an optimal carbon dioxide diffusion coefficient (DCO₂) and tidal volume (VT) have not yet been established due to much individual variance. This study aimed to analyze DCO₂ values, VT, and minute volume in very-low-birth-weight (VLBW) infants using HFOV and correlates with plasma CO₂ (pCO₂). MATERIALS AND METHODS: Daily respiratory mechanics and ventilator settings from twenty VLBW infants and their two hundred seventeen results of blood gas analysis were collected. Patients were treated with the Dräger Babylog VN500 ventilator (Drägerwerk Ag & Co.) in HFOV mode. The normocapnia was indicated as pCO₂ ranging from 45 mm Hg to 55 mm Hg. RESULTS: The measured VT was 1.7 mL/kg, minute volume was 0.7 mL/kg, and DCO₂ was 43.5 mL²/s. Mean results of the blood gas test were as follows: pH, 7.31; pCO₂, 52.6 mm Hg; and SpO₂, 90.5%. In normocapnic state, the mean VT was significantly higher than in hypercapnic state (2.1±0.5 mL/kg vs. 1.6±0.3 mL/kg), and the mean DCO₂ showed significant difference (68.4±32.7 mL²/s vs. 32.4±15.7 mL²/s). The DCO₂ was significantly correlated with the pCO₂ (p=0.024). In the receiver operating curve analysis, the estimated optimal cut-off point to predict the remaining normocapnic status was a VT of 1.75 mL/kg (sensitivity 73%, specificity 80%). CONCLUSION: In VLBW infants treated with HFOV, VT of 1.75 mL/kg is recommended for maintaining proper ventilation.
Blood Gas Analysis ; Carbon Dioxide/analysis ; Female ; High-Frequency Ventilation ; Humans ; Hypercapnia/physiopathology ; Incidence ; Infant ; Infant, Newborn ; Infant, Very Low Birth Weight/physiology ; Male ; ROC Curve ; Tidal Volume

OBJECTIVETo study the clinical effect and safety of bubble nasal continuous positive airway pressure (BNCPAP) versus conventional nasal continuous positive airway pressure (nCPAP) in respiratory support for preterm infants with neonatal respiratory distress syndrome (NRDS).

METHODSA retrospective analysis was performed for the clinical data of 130 preterm infants with NRDS. Among them, 69 underwent BNCPAP and 61 underwent nCPAP. The two groups were compared in terms of mortality rate, duration of respiratory support, use of pulmonary surfactant (PS), and treatment failure rate, and the incidence rates of bronchopulmonary dysplasia (BPD) and retinopathy of prematurity (ROP), as well as the changes in blood gas pH, partial pressure of oxygen, and partial pressure of carbon dioxide. The safety was evaluated for both groups.

RESULTSThere were no significant differences between the BNCPAP group and the nCPAP group in sex distribution, gestational age, birth weight, Apgar score at 1 and 5 minutes after birth, delivery mode, and the severity of NRDS (P>0.05). No infants in the BNCPAP group died, and one infant in the nCPAP group died; there was no significant difference in the mortality rate between the two groups (P>0.05). There were also no significant differences between the two groups in the duration of noninvasive ventilation, treatment failure rate, the incidence rates of BPD and ROP, and the percentage of infants with a need for use or reuse of PS (P>0.05). After 8-12 hours of ventilation, there were no significant differences between the two groups in the changes in blood gas pH and oxygenation index (P>0.05), while the BNCPAP group had a significantly greater reduction in partial pressure of carbon dioxide than the nCPAP group (P<0.05). There were no significant differences between the two groups in the incidence rates of pneumothorax, nasal septal injury, and nasal mucosal injury (P>0.05).

CONCLUSIONSBNCPAP and nCPAP have similar clinical effect and safety in respiratory support for preterm infants with NRDS.

Blood Gas Analysis ; Carbon Dioxide ; analysis ; blood ; Continuous Positive Airway Pressure ; methods ; Female ; Gestational Age ; Humans ; Infant, Newborn ; Infant, Premature ; blood ; Male ; Oxygen ; analysis ; blood ; Pneumothorax ; therapy ; Respiratory Distress Syndrome, Newborn ; blood ; therapy ; Retrospective Studies ; Treatment Failure

Severe eating disorders characterized by repetitive episodes of purging and vomiting can occasionally trigger acute kidney injury. However, interstitial nephritis induced by episodes of repeated vomiting has rarely been reported, and the pathophysiology of this entity remains unknown. A 26-year-old man was admitted to our hospital because of known hypokalemia. His serum electrolyte profile showed: sodium 133 mEq/L, potassium 2.6 mEq/L, chloride 72 mEq/L, total carbon dioxide 50 mEq/L, blood urea nitrogen/creatinine ratio (BUN/Cr) 21.9/1.98 mg/dL, and magnesium 2.0 mg/dL. Arterial blood gas analysis showed: pH 7.557, partial pressure of carbon dioxide 65.8 mmHg, and bicarbonate 58.5 mEq/L. His urinary potassium concentration was 73.2 mEq/L, and Cr was 111 mg/dL. Renal biopsy revealed acute tubular necrosis and tubulointerstitial nephritis with a few shrunken glomeruli. Repeated psychogenic vomiting may precipitate acute kidney injury and interstitial nephritis secondary to volume depletion and hypokalemia. Serum electrolyte levels and renal function should be carefully monitored in patients diagnosed with eating disorders to prevent tubular ischemia and interstitial nephritis.
Acute Kidney Injury ; Adult ; Anorexia Nervosa* ; Anorexia* ; Biopsy ; Blood Gas Analysis ; Carbon Dioxide ; Eating ; Humans ; Hydrogen-Ion Concentration ; Hypokalemia ; Ischemia ; Magnesium ; Male* ; Necrosis ; Nephritis, Interstitial* ; Partial Pressure ; Potassium ; Sodium ; Urea ; Vomiting

OBJECTIVE: This study examined the initial partial pressure of carbon dioxide (PCO₂) as a possible indicator of prehospital ventilation and its association with prehospital i-gel in out-of-hospital cardiac arrest (OHCA) patients. METHODS: The demographics and arrest parameters, including i-gel insertion and initial arterial blood gas analysis, of OHCA patients who visited the emergency department were analyzed retrospectively. Linear regression analysis was performed to examine the association between i-gel insertion and the initial PCO₂. RESULTS: A total of 106 patients were investigated. Fifty-six patients had prehospital i-gel insertion and 50 patients did not have a prehospital advanced airway. The initial PCO₂ was higher in the i-gel group than the no advanced airway group (105.2 mmHg [77.5–134.9] vs. 87.5 mmHg [56.8–115.3], P=0.03). Prehospital i-gel insertion was associated with a higher initial PCO₂ level (βcoefficient, 20.3; 95% confidence interval, 2.6–37.9; P=0.03). CONCLUSION: Prehospital insertion of i-gel was associated with higher initial PCO₂ values in OHCA patients compared to no advanced airway.
Airway Management ; Blood Gas Analysis ; Carbon Dioxide ; Cardiopulmonary Resuscitation ; Demography ; Emergency Medical Services ; Emergency Service, Hospital ; Heart Arrest ; Humans ; Linear Models ; Out-of-Hospital Cardiac Arrest* ; Partial Pressure ; Retrospective Studies ; Ventilation

BACKGROUND: Blood gas analysis plays a crucial role in critical care settings, and immediate and precise analysis improves clinical outcomes through prompt treatment. We evaluated the performance of a cartridge-type blood gas analyzer, i-Smart 300 (i-SENS, Korea), according to the Clinical and Laboratory Standard Institute (CLSI) guidelines and compared it to a conventional blood gas analyzer. METHODS: The precision was evaluated according to CLSI EP5-A3. The i-Smart 300 was compared to the Stat Profile Critical Care Xpress (STP CCX) (Nova CCX; Nova Biomedical, USA) according to CLSI EP9-A3 using the following eight parameters: pH, partial carbon dioxide pressure, partial oxygen pressure, sodium, potassium, chloride, ionized calcium, and hematocrit. Linearity was determined using five levels of control materials according to CLSI EP6-A. RESULTS: Within-run precision and total precision, demonstrated as coefficients of variation, ranged from 0.02 to 2.50% and from 0.05 to 3.46%, respectively. Correlation analysis yielded a correlation coefficient from 0.966 to 0.996 between the i-Smart 300 and the conventional analyzer (Nova CCX). The i-Smart 300 showed excellent linearity at eight parameters with acceptable percent recovery. CONCLUSIONS: The i-Smart 300, a portable cartridge-type blood gas analyzer, showed high precision and good correlation with a traditional bench-top blood gas analyzer. It could be useful in critical care settings.
Blood Gas Analysis ; Calcium ; Carbon Dioxide ; Critical Care ; Hematocrit ; Hydrogen-Ion Concentration ; Oxygen ; Partial Pressure ; Point-of-Care Systems ; Potassium ; Sodium

Severe hypercapnia can be predicted by a decrease in cerebral electrical activity. The authors describe a sudden decrease in spectral entropy due to severe hypercapnia-induced respiratory acidosis in a patient with chronic pulmonary obstructive disease during lung resection. After two and a half hours of low tidal volume ventilation in the lateral position, the state entropy suddenly dropped from 45 to 7, without any changes in the effect-site concentration of propofol, end-tidal carbon dioxide (CO₂) tension, oxygen saturation, or arterial pressure. However, arterial blood gas analysis showed severe respiratory acidosis (pH 7.01, PaCO₂ 115 mmHg and PaO₂ 246 mmHg with FIO₂ of 0.5). Immediate hyperventilation improved the state entropy and acid-base balance. Electroencephalography-based spectral entropy can detect severe hypercapnia in chronic pulmonary obstructive disease patients with a large arterial to end-tidal CO2 difference due to prolonged hypoventilation during thoracic surgery.
Acid-Base Equilibrium ; Acidosis, Respiratory ; Arterial Pressure ; Blood Gas Analysis ; Carbon Dioxide ; Electroencephalography ; Entropy* ; Humans ; Hypercapnia* ; Hyperventilation ; Hypoventilation ; Lung ; Oxygen ; Propofol ; Thoracic Surgery ; Tidal Volume* ; Ventilation