Relationship Between Partial Carbon Dioxide Pressure and Strong Ions in Humans: A Retrospective Study.

Little is known about the role of a strong ions in humans with respiratory abnormalities. In this study, we investigated the associations between partial carbon dioxide pressure (pCO2) and each of sodium ion (Na+) concentrations, chloride ion (Cl-) concentrations and their difference (SIDNa-Cl). Blood gas data were obtained from patients in a teaching hospital intensive care unit between August 2013 and January 2017. The association between pCO2 and SIDNa-Cl was defined as the primary outcome. The associations between pCO2 and [Cl-], [Na+] and other strong ions were secondary outcomes. pCO2 was stratified into 10 mmHg-wide bands and treated as a categorical variable for comparison. As a result, we reviewed 115,936 blood gas data points from 3,840 different ICU stays. There were significant differences in SIDNa-Cl, [Cl-], and [Na+] among all categorized pCO2 bands. The respective pCO2 SIDNa-Cl, [Cl-], and [Na+] correlation coefficients were 0.48, -0.31, and 0.08. SIDNa-Cl increased and [Cl-] decreased with pCO2, with little relationship between pCO2 and [Na+] across subsets. In conclusion, we found relatively strong correlations between pCO2 and SIDNa-Cl in the multiple blood gas datasets examined. Correlations between pCO2 and chloride concentrations, but not sodium concentrations, were further found to be moderate in these ICU data.

Evaluation of a point-of-care serum creatinine measurement device and the impact on diagnosis of acute kidney injury in pediatric cardiac patients: A retrospective, single center study.

BACKGROUND AND AIMS: Agreement between measurements of creatinine concentrations using point-of-care (POC) devices and measurements conducted in a standard central laboratory is unclear for pediatric patients. Our objectives were (a) to assess the agreement for pediatric patients and (b) to compare the incidence of postoperative acute kidney injury (AKI) according to the two methods. METHODS: This retrospective, single-center study included patients under 18 years of age who underwent cardiac surgery and who were admitted into the pediatric intensive care unit of a tertiary teaching hospital (Okayama University Hospital, Japan) from 2013 to 2017. The primary objective was to assess the correlation and the agreement between measurements of creatinine concentrations by a Radiometer blood gas analyzer (Cregas) and those conducted in a central laboratory (Crelab). The secondary objective was to compare the incidence of postoperative AKI between the two methods based on Kidney Disease Improving Global Outcomes (KDIGO) criteria. RESULTS: We analyzed the results of 1404 paired creatinine measurements from 498 patients, whose median age was 14 months old (interquartile range [IQR] 3, 49). The Pearson correlation coefficient of Cregas vs Crelab was 0.968 (95% confidence interval [CI], 0.965-0.972, P < 0.001). The median bias between Cregas and Crelab was 0.02 (IQR -0.02, 0.05) mg/dL. While 199 patients (40.0%) were diagnosed as having postoperative AKI based on Crelab, 357 patients (71.7%) were diagnosed as having postoperative AKI based on Cregas (Kappa = 0.39, 95% CI, 0.33-0.46). In a subgroup analysis of patients whose Cregas and Crelab were measured within 1 hour, similar percentage of patients were diagnosed as having postoperative AKI based on Cregas and Crelab (42.8% vs 46.0%; Kappa = 0.76, 95% CI, 0.68-0.84). CONCLUSION: There was an excellent correlation between Cregas and Crelab in pediatric patients. Although more patients were diagnosed as having postoperative AKI based on Cregas than based on Crelab, paired measurements with a short time gap showed good agreement on AKI diagnosis.

Prolonged Tachycardia with Higher Heart Rate Is Associated with Higher ICU and In-hospital Mortality.

Tachycardia is common in intensive care units (ICUs). It is unknown whether tachycardia or prolonged tachycardia affects patient outcomes. We investigated the association between tachycardia and mortality in critically ill patients. This retrospective cohort study's primary outcome was patient mortality in the ICU and the hospital. We stratified the patients (n=476) by heart rate (HR) as LowHR, MediumHR, and HighHR groups. We also stratified them by their durations of HR >100 (prolonged HR; tachycardia): MildT, ModerateT, and SevereT groups. We determined the six groups' mortality. The ICU mortality rates of the LowHR, MediumHR, and HighHR groups were 1.0%, 1.5%, and 7.9%, respectively; significantly higher in the HighHR vs. LowHR group. The in-hospital mortality rates of these groups were 1%, 4.5%, and 14.6%, respectively; significantly higher in the HighHR vs. LowHR group. The ICU mortality rates of the MildT, ModerateT, and SevereT groups were 0.9%, 5.6%, and 57.1%, respectively. The mortality of the HRT=0 (i.e., all HR ≤ 100) patients was 0%. The in-hospital mortality rates of the MildT, ModerateT, and SevereT groups were 1.8%, 16.7%, and 85.7%, respectively; that of the HRT=0 patients was 0.5%. Both higher HR and prolonged tachycardia were associated with poor outcomes.

Hyperchloremia Is Not an Independent Risk Factor for Postoperative Acute Kidney Injury in Pediatric Cardiac Patients.

OBJECTIVE: Hyperchloremia recently has been shown to have an association with the development of acute kidney injury (AKI) in critically ill patients. However, there is little information about the prevalence of an abnormal chloride concentration after pediatric cardiac surgery and its association with postoperative AKI. The aim of this study was to determine the prevalence of hyperchloremia and its association with AKI in pediatric patients after cardiac surgery. DESIGN: A retrospective single-center study. SETTING: Referral high-volume pediatric cardiac center in a tertiary teaching hospital. PARTICIPANTS: Patients under 72 months of age with congenital heart disease who underwent cardiac surgery with the use of cardiopulmonary bypass. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The primary outcome was development of AKI diagnosed by Kidney Disease Improving Global Outcomes consensus criteria. The associations of outcomes with the highest serum chloride concentration ([Cl-]max) and time-weighted average chloride concentration ([Cl-]ave) within the first 48 hours after surgery were investigated. Of 521 patients included in the study, 463 patients (88.9%) had hyperchloremia at least 1 time within the first 48 hours after surgery. Postoperative AKI occurred in 205 patients (39.3%). [Cl-]ave and [Cl-]max in the AKI group were significantly higher than those in the non-AKI group (112 [110-114] mEq/L v 111 [109-113] mEq/L, p = 0.001 and 116 [113, 119] mEq/L v 114 [112-118] mEq/L, p = 0.002, respectively). After adjustment for other predictors of AKI by multivariable analyses, neither [Cl-]ave nor [Cl-]max was associated independently with the development of AKI (odds ratio [OR] = 1.040, 95% confidence interval [CI]: 0.885-1.220, p = 0.63; OR = 0.992, 95% CI: 0.874-1.130. p = 0.90). CONCLUSION: Postoperative hyperchloremia was common and was associated with the development of AKI in pediatric patients after congenital cardiac surgery in univariate analysis. After adjustment for predictors of AKI by multivariate analyses, there was no significant relationship between postoperative chloride concentration and AKI.