Factors associated with carbon dioxide transfer in an experimental model of severe acute kidney injury and hypoventilation during high bicarbonate continuous renal replacement therapy and oxygenation membrane support.

OBJECTIVE: To investigate the factors influencing carbon dioxide transfer in a system that integrates an oxygenation membrane in series with high-bicarbonate continuous veno-venous hemodialysis in hypercapnic animals. METHODS: In an experimental setting, we induced severe acute kidney injury and hypercapnia in five female Landrace pigs. Subsequently, we initiated high (40mEq/L) bicarbonate continuous veno-venous hemodialysis with an oxygenation membrane in series to maintain a pH above 7.25. At intervals of 1 hour, 6 hours, and 12 hours following the initiation of continuous veno-venous hemodialysis, we performed standardized sweep gas flow titration to quantify carbon dioxide transfer. We evaluated factors associated with carbon dioxide transfer through the membrane lung with a mixed linear model. RESULTS: A total of 20 sweep gas flow titration procedures were conducted, yielding 84 measurements of carbon dioxide transfer. Multivariate analysis revealed associations among the following (coefficients ± standard errors): core temperature (+7.8 ± 1.6 °C, p < 0.001), premembrane partial pressure of carbon dioxide (+0.2 ± 0.1/mmHg, p < 0.001), hemoglobin level (+3.5 ± 0.6/g/dL, p < 0.001), sweep gas flow (+6.2 ± 0.2/L/minute, p < 0.001), and arterial oxygen saturation (-0.5 ± 0.2%, p = 0.019). Among these variables, and within the physiological ranges evaluated, sweep gas flow was the primary modifiable factor influencing the efficacy of low-blood-flow carbon dioxide removal. CONCLUSION: Sweep gas flow is the main carbon dioxide removal-related variable during continuous veno-venous hemodialysis with a high bicarbonate level coupled with an oxygenator. Other carbon dioxide transfer modulating variables included the hemoglobin level, arterial oxygen saturation, partial pressure of carbon dioxide and core temperature. These results should be interpreted as exploratory to inform other well-designed experimental or clinical studies.

Independent variables of pH: Ten Knights of the Hydrogen Ion Kingdom-Part I. A prospective observational study.

CO2, HCO3, SID, and total weak acids have been defined as pH's independent variables. However, according to Gamble, HCO3 should be equal to the difference between the sum of cations and the sum of anions besides HCO3. Therefore, if this mathematical expression is substituted for HCO3 in the Henderson-Hasselbalch equation, all independent variables of pH can be demonstrated. Our aim is to test this theory in this study. This prospective observational study was conducted between 2019 and 2020. All admitted patients to the intensive care unit who were >18 years old were included. Demographic data, blood gas parameters, albumin, magnesium, and inorganic phosphorus levels, and outcomes were recorded twice (at admission and at the 24th hour). The multivariate linear regression model was used to determine pH's independent variables. In the multivariate linear regression model, pH was significantly increased by each unit increase in Na, K, Ca, and Mg (mmol L-1). In contrast, pH was significantly decreased by each unit increase in CO2, Cl, lactate, albumin (g dL-1), inorganic phosphorus (mg dL-1), and the strong ion gap. Ten independent variables can accurately predict the changes in pH. For this reason, all ten independent variables should be separately evaluated when interpreting the acid-base status. With this understanding, all algorithms regarding acid-base evaluation may become unnecessary.

Exploring the Influence of Acid-Base Status on Athletic Performance during Simulated Three-Day 400 m Race.

This study aimed to investigate the ability of highly trained athletes to consistently perform at their highest level during a simulated three-day 400 m race and to examine the impact of an alkaline diet associated with chronic consumption of bicarbonate-rich water or placebo on their blood metabolic responses before and after the three races. Twenty-two highly trained athletes, divided into two groups-one with an alkalizing diet and placebo water (PLA) and the other with an alkalizing diet and bicarbonate-rich water (BIC)-performed a 400 m race for three consecutive days. Performance metrics, urine and blood samples assessing acid-base balance, and indirect markers of neuro-muscular fatigue were measured before and after each 400 m race. The evolution of the Potential Renal Acid Load (PRAL) index and urinary pH highlights the combination of an alkalizing diet and bicarbonate-rich hydration, modifying the acid-base state (p < 0.05). Athletes in the PLA group replicated the same level of performance during three consecutive daily races without an increase in fatigue-associated markers. Athletes experienced similar levels of metabolic perturbations during the three 400 m races, with improved lactate clearance 20 min after the third race compared to the first two (p < 0.05). This optimization of the buffering capacity through ecological alkaline nutrition and hydration allowed athletes in the BIC group to improve their performance during the third 400 m race (p < 0.01). This study highlights athletes' ability to replicate high-level performances over three consecutive days with the same extreme level of metabolic disturbances, and an alkaline diet combined with bicarbonate-rich water consumption appears to enhance performance in a 400 m race.

Bicarbonate and Serum Lab Markers as Predictors of Mortality in the Trauma Patient.

Introduction: Severe trauma-induced blood loss can lead to metabolic acidosis, shock, and death. Identification of abnormalities in the bicarbonate and serum markers may be seen before frank changes in vital signs in the hemorrhaging trauma patient, allowing for earlier lifesaving interventions. In this study the author aimed to evaluate the usefulness of serum bicarbonate and other lab markers as predictors of mortality in trauma patients within 30 days after injury. Methods: This retrospective, propensity-matched cohort study used the TriNetX database, covering approximately 92 million patients from 55 healthcare organizations in the United States, including 3.8 million trauma patients in the last two decades. Trauma patients were included if they had lab measurements available the day of the event. The analysis focused on mortality within 30 days post-trauma in comparison to measured lab markers. Cohorts were formed based on ranges of bicarbonate, lactate, and base excess levels. Results: Before propensity score matching, a total of 1,275,363 trauma patients with same-day bicarbonate, lactate, or base excess labs were identified. A significant difference in mortality was found across various serum bicarbonate lab ranges compared to the standard range of 21-27 milliequivalents per liter (mEq/L), post-propensity score matching. The relative risk of death was 6.806 for bicarbonate ≤5 mEq/L; 8.651 for 6-10; 6.746 for 11-15; 2.822 for 16-20; and 1.015 for bicarbonate ≥28. Serum lactate also displayed significant mortality outcomes when compared to a normal level of ≤2 millimoles per liter. Base excess showed similar significant correlation at different values compared to a normal base excess of -2 to 2 mEq/L. Conclusion: This study, approximately 100 times larger than prior studies, associated lower bicarbonate levels with increased mortality in the trauma patient. While lactate and base excess offer prognostic value, lower bicarbonate values have a higher relative risk of death. The greater predictive value of bicarbonate and accessibility during resuscitations suggests that it may be the superior prognostic marker in trauma.

The effect of serum biochemical parameters on clinical prognosis in children presenting with diabetic ketoacidosis.

OBJECTIVE: The aim of this study was to determine whether diabetes mellitus has a high risk of diabetic ketoacidosis-related complications. Biochemical parameters affect the resolution time of diabetic ketoacidosis. METHODS: The present study is based on a retrospective evaluation of the records of patients who presented to the Pediatrics Clinic of Adiyaman University Hospital between January 1, 2017, and October 1, 2022, with a diagnosis ofdiabetic ketoacidosis. The demographic characteristics, serum biochemical parameters, blood gas results, and time to transition to subcutaneous insulin therapy were all recorded. RESULTS: This study included 49 (49%) female and 51 (51%) male patients aged 1-17 years (mean age: 9.05±4.33 years). The average time to clinical improvement of the sample, that is, transition to subcutaneous insulin therapy, was 21.04±7.8 h. An evaluation of the presence of acute kidney injury based on serum urea and creatinine levels and eGFR values revealed no significant effect on the rate of clinical recovery (respective p-values: p=0.076, p=0.494, and p=0.884). A univariate analysis identified blood glucose (p=0.025), blood gas pH (p<0.001), and blood bicarbonate (p=0.004) values as prognostic factors, while a multivariate analysis revealed pH values had an independent and significant effect on the resolution time of diabetic ketoacidosis. CONCLUSION: Serum glucose, pH, and bicarbonate levels are the most important determinants of clinical prognosis in patients with diabetic ketoacidosis. These findings can serve as a guide for clinicians in the follow-up and treatment of such patients.

Evaluation of agreement between a noninvasive method for real-time measurement of critical blood values with a standard point-of-care device.

The purpose of this work was to investigate the degree of agreement between two distinct approaches for measuring a set of blood values and to compare comfort levels reported by participants when utilizing these two disparate measurement methods. Radial arterial blood was collected for the comparator analysis using the Abbott i-STAT® POCT device. In contrast, the non-invasive proprietary DBC methodology is used to calculate sodium, potassium, chloride, ionized calcium, total carbon dioxide, pH, bicarbonate, and oxygen saturation using four input parameters (temperature, hemoglobin, pO2, and pCO2). Agreement between the measurement for a set of blood values obtained using i-STAT and DBC methodology was compared using intraclass correlation coefficients, Passing and Bablok regression analyses, and Bland Altman plots. A p-value of <0.05 was considered statistically significant. A total of 37 participants were included in this study. The mean age of the participants was 42.4 ± 13 years, most were male (65%), predominantly Caucasian/White (75%), and of Hispanic ethnicity (40%). The Intraclass Correlation Coefficients (ICC) analyses indicated agreement levels ranging from poor to moderate between i-STAT and the DBC's algorithm for Hb, pCO2, HCO3, TCO2, and Na, and weak agreement for pO2, HSO2, pH, K, Ca, and Cl. The Passing and Bablok regression analyses demonstrated that values for Hb, pO2, pCO2, TCO2, Cl, and Na obtained from the i-STAT did not differ significantly from that of the DBC's algorithm suggesting good agreement. The values for Hb, K, and Na measured by the DBC algorithm were slightly higher than those obtained by the i-STAT, indicating some systematic differences between these two methods on Bland Altman Plots. The non-invasive DBC methodology was found to be reliable and robust for most of the measured blood values compared to invasive POCT i-STAT device in healthy participants. These findings need further validation in larger samples and among individuals afflicted with various medical conditions.

Hypocapnia in women with fibromyalgia.

OBJECTIVES: The purpose of this study was to investigate whether people with fibromyalgia (FM) have dysfunctional breathing by examining acid-base balance and comparing it with healthy controls. METHODS: Thirty-six women diagnosed with FM and 36 healthy controls matched for age and gender participated in this cross-sectional study. To evaluate acid-base balance, arterial blood was sampled from the radial artery. Carbon dioxide, oxygen, bicarbonate, base excess, pH and lactate were analysed for between-group differences. Blood gas analyses were performed stepwise on each individual to detect acid-base disturbance, which was categorized as primary respiratory and possible compensation indicating chronicity. A three-step approach was employed to evaluate pH, carbon dioxide and bicarbonate in this order. RESULTS: Women with FM had significantly lower carbon dioxide pressure (p = 0.013) and higher lactate (p = 0.038) compared to healthy controls at the group level. There were no significant differences in oxygen pressure, bicarbonate, pH and base excess. Employing a three-step acid-base analysis, 11 individuals in the FM group had a possible renally compensated mild chronic hyperventilation, compared to only 4 among the healthy controls (p = 0.042). CONCLUSIONS: In this study, we could identify a subgroup of individuals with FM who may be characterized as mild chronic hyperventilators. The results might point to a plausible dysfunctional breathing in some women with FM.

Blood chloride abnormalities in diarrheic neonatal calves with metabolic acidosis.

The present study investigated the prevalence of blood chloride (Cl) abnormalities in diarrheic neonatal calves with metabolic acidosis and attempted to identify the most relevant electrolyte abnormality to these abnormalities. A retrospective analysis was conducted on the medical records of 157 diarrheic neonatal calves aged 10.3 ± 4.2 days old with metabolic acidosis. Hypochloremia, normochloremia, and hyperchloremia were observed in 8.9% (14/157), 43.3% (68/157), and 47.8% (68/157), respectively, of diarrheic calves with metabolic acidosis. This distribution remained similar regardless of age (under 8 days or 8 days and older). Furthermore, a multiple logistic regression analysis showed that variations in values for blood sodium [Na (regression coefficients 0.877; 95% confidence interval (CI) 13.977-134.195; P<0.01)], pH (regression coefficients -10.719; 95% CI -19.076- -2.362; P<0.05), and bicarbonate [HCO3- (regression coefficients -0.555; 95% CI -0.820- -0.290; P<0.01)] were associated with blood Cl abnormalities. The present results revealed that blood Na concentrations were more strongly associated with blood Cl concentrations than blood pH and HCO3- values. In the present study, diarrheic calves with hyperchloremia were characterized by normonatremia and extremely severe metabolic acidosis.

Spurious hyperbicarbonatemia and a negative anion gap in a cat and a dog with severe rhabdomyolysis.

A 3-year-old male neutered domestic shorthair cat and a 2-year-old male neutered Labrador-mix dog were separately presented to the Veterinary Medical Center for evaluation after sustaining significant muscle trauma due to a dog attack and seizure activity, respectively. In both cases, biochemical analysis was consistent with rhabdomyolysis. Additionally, a markedly increased measured serum bicarbonate concentration and negative calculated anion gap were observed. As these biochemical abnormalities were not expected and deemed incompatible with life, an interference with the analyzer measurement of bicarbonate involving marked increases in pyruvate and lactate dehydrogenase (LDH) following myocyte injury was suspected. Venous blood gas analysis calculated bicarbonate concentration and anion gap were within reference interval, while measured LDH activity was markedly increased. These findings supported an analyzer-generated interference. This is the first published report of a previously described chemistry analyzer interference of markedly increased LDH activity with serum bicarbonate concentration measurement in dogs and cats. Awareness of this interference is important, particularly in the emergency setting, as it may influence case management.

Unmasking the escalation: a comparative analysis of diabetic ketoacidosis severity before and during the COVID-19 pandemic in a Tunisian pioneer study.

BACKGROUND: The severity of diabetic ketoacidosis (DKA) at diagnosis increased during the global COVID-19 pandemic. This study aimed to analyze the impact of the pandemic on the clinical and biological severity of DKA in patients with new-onset diabetes mellitus (DM) in Tunisia. RESEARCH DESIGN AND METHODS: The study included patients hospitalized for new-onset DKA 2 years prior and 2 years during the COVID-19 pandemic. Data was collected retrospectively, and DKA severity was classified based on biological parameters like potential of hydrogen (pH) and HCO3-. RESULTS: The results showed that DKA was more severe during COVID-19, as evidenced by lower potential of hydrogen (pH) (p = 0.006), and serum bicarbonate (HCO3-) levels (p = 0,005). Despite the higher severity of DKA was higher during COVID-19, intensive care unit hospitalizations remained equivalent (p = 0.359). The prevalence of hyponatremia was also higher during COVID-19 (p = 0.024). CONCLUSION: The findings suggest that delayed diagnosis and COVID-19 May contribute to the increased severity of DKA and electrolyte imbalance during the pandemic. Further research is needed to better understand the underlying mechanisms and develop appropriate strategies to address this issue.

Prognostic values of serum lactate-to-bicarbonate ratio and lactate for predicting 28-day in-hospital mortality in children with dengue shock syndrome.

This study aimed to assess the clinical utility of blood lactate-to-bicarbonate (L/B) ratio, as a prognostic factor for 28-day in-hospital mortality in children with dengue shock syndrome (DSS), admitted to the pediatric intensive care unit (PICU). This single-center retrospective study was conducted at a tertiary children hospital in southern Vietnam from 2013 to mid-2022. Prognostic models for DSS mortality were developed, using a predefined set of covariates in the first 24 hours of PICU admission. Area under the curves (AUCs), multivariable logistic and Least Absolute Shrinkage and Selection Operator (LASSO) regressions, bootstrapping and calibration slope were performed. A total of 492 children with DSS and complete clinical and biomarker data were included in the analysis, and 26 (5.3%) patients died. The predictive values for DSS mortality, regarding lactate showing AUC 0.876 (95% CI, 0.807-0.944), and that of L/B ratio 0.867 (95% CI, 0.80-0.934) (P values of both biomarkers < .001). The optimal cutoff point of the L/B ratio was 0.25, while that of lactate was 4.2 mmol/L. The multivariable model showed significant clinical predictors of DSS fatality including severe bleeding, cumulative amount of fluid infused and vasoactive-inotropic score (>30) in the first 24 hours of PICU admission. Combined with the identified clinical predictors, the L/B ratio yielded higher prognostic values (odds ratio [OR] = 8.66, 95% confidence interval [CI], 1.96-38.3; P < .01) than the lactate-based model (OR = 1.35, 95% CI, 1.15-1.58; P < .001). Both the L/B and lactate models showed similarly good performances. Considering that the L/B ratio has a better prognostic value than the lactate model, it may be considered a potential prognostic biomarker in clinical use for predicting 28-day mortality in PICU-admitted children with DSS.

Serum bicarbonate levels and kidney outcomes in critically ill patients: a prospective cohort study.

BACKGROUND: The interplay between serum bicarbonate levels and kidney outcomes is not fully understood. We conducted a prospective cohort study in three intensive care units (ICUs) to evaluate the association of serum bicarbonate levels with acute kidney injury (AKI) and kidney function recovery in critically ill patients. METHODS: A prospective cohort study in three intensive care units (ICUs) was performed. The serum bicarbonate level in the first 24 h after ICU admission was categorized as low (< 22 mEq/L), normal (22-26 mEq/L), or high (> 26 mEq/L). Serum creatinine (SCr) levels according to the KDIGO AKI guideline were used for defining AKI within the first 7 days of ICU stay. At ICU admission, SCr ≥ 1.1 for women and ≥ 1.3 mg/dL for men were indicative of impaired kidney function. Mortality outcome was tracked up to 28 days, and kidney function recovery was assessed at hospital discharge. RESULTS: A total of 2732 patients (66 ± 19 years and 55% men) were analyzed, with 32% having impaired kidney function at ICU admission. Overall, 26% of patients had low bicarbonate levels, while 32% had high bicarbonate levels. Notably, patients with preserved kidney function showed a lower prevalence of low bicarbonate levels compared to those with impaired kidney function (20% vs. 39%, p < 0.001), while higher rates were observed for high bicarbonate (35% vs. 24%, p < 0.001). Compared with patients with normal serum bicarbonate levels, those with low bicarbonate were 81% more likely to develop AKI (OR = 1.81; 95% CI 1.10-2.99), whereas those with high bicarbonate were 44% less likely (OR = 0.56; 95% CI 0.32-0.98) in the adjusted model for confounders. Neither those with high nor low serum bicarbonate levels were associated with an increased risk of mortality (HR = 1.03; 95% CI 0.68-1.56 and 0.99; 95% CI 0.68-1.42, respectively). In subgroup analysis, regardless of the kidney function at ICU admission, serum bicarbonate levels were not associated with the development of AKI and all-cause mortality. Regarding kidney function recovery, higher non-recovery rates were found for those with low bicarbonate. CONCLUSION: In critically ill ICU patients, low bicarbonate levels were associated with the more likely development of AKI and subsequent non-recovery of kidney function, while high bicarbonate levels showed no such association. Therefore, low bicarbonate levels may be considered a risk factor for adverse kidney outcomes in critically ill patients.

Perioperative Evaluation of Arterial and Venous Whole Blood in the Lamb (Ovis aries) Fontan Model.

Whole blood analysis can evaluate numerous parameters, including pH, pCO2, pO2, HCO3 - , base excess, glucose, electrolytes, lactate, blood urea nitrogen, creatinine, bilirubin, and hemoglobin. This valuable tool enables clinicians to make more informed decisions about patient care. However, the current body of literature describing perioperative whole blood analysis in Dorset sheep (Ovis aries) is small, so clinicians lack adequate information to guide their decision-making when evaluating test results. We evaluated arterial and venous whole blood pH, bicarbonate, pCO2, lactate, creatinine, and blood urea nitrogen before and for the first 24 hours after surgery in 2 cohorts of male and female Ovis arie s undergoing one of 2 major cardiovascular procedures, a Single-Stage Fontan or an inferior vena cava to pulmonary artery extracardiac conduit implantation (IP-ECC). The cohort undergoing a Single-Stage Fontan, which is the more complex procedure, exhibited greater deviation from baseline measurements than did the cohort undergoing the IP-ECC for lactate, bicarbonate, and creatinine. The cohort undergoing the IP-ECC showed no significant deviation from baseline for any parameters, potentially indicating a better safety margin than expected when compared with the Single-Stage Fontan. Together, these results indicate the clinical value of arterial and venous whole blood measurements in perioperative management of sheep and can provide a reference for clinicians managing sheep after significant cardiovascular procedures.

Lower bicarbonate level is associated with CKD progression and all-cause mortality: a propensity score matching analysis.

BACKGROUND: Although metabolic acidosis is known as a potential complication of chronic kidney disease (CKD), there is limited information concerning the association between metabolic acidosis and clinical outcomes. METHODS: Five hundred fifty-two patients referred to renal division of Iwata City Hospital from 2015 to 2017 were included as a retrospective CKD cohort, and finally 178 patients with CKD stage III or IV and 20 to 80 years of age were analyzed. We examined the association between serum bicarbonate (HCO3-) levels and clinical outcomes using Kaplan-Meier methods after the matching of baseline characteristics by propensity scores. RESULTS: Of 178 patients with CKD, patients with lower HCO3- levels (N = 94), as compared with patients with higher HCO3- levels (N = 84), were more likely to be male (P < 0.05), had more severe CKD stages (P < 0.05), more frequent use of renin-angiotensin system inhibitor (P < 0.05) or uric acid lowering agent (P < 0.001), heavier body weight (P < 0.001) and lower estimated glomerular filtration rate (P < 0.05). In Kaplan-Meier analysis after propensity score matching, the incidence of composite outcome as the doubling of serum creatinine level from baseline, end-stage kidney disease requiring the initiation of dialysis, or death from any causes was significantly fewer in the higher HCO3- group than the lower HCO3- group (N = 57 each group, P = 0.016). CONCLUSIONS: Lower HCO3- level is significantly associated with the doubling of serum creatinine level, end-stage kidney disease or all-cause mortality in patients with CKD. TRIAL REGISTRATION: This study was registered with the Clinical Trial Registry of the University Hospital Medical Information Network ( http://www.umin.ac.jp/ , study number: UMIN000044861 ).

Effects of veverimer on serum bicarbonate and physical function in women with chronic kidney disease and metabolic acidosis: a subgroup analysis from a randomised, controlled trial.

BACKGROUND: Globally, the prevalence of chronic kidney disease (CKD) is higher in women than in men; however, women have been historically under-represented in nephrology clinical trials. Metabolic acidosis increases risk of progressive loss of kidney function, causes bone demineralization and muscle protein catabolism, and may be more consequential in women given their lower bone and muscle mass. Veverimer, an investigational, non-absorbed polymer that binds and removes gastrointestinal hydrochloric acid, is being developed as treatment for metabolic acidosis. METHODS: This was a Phase 3, multicenter, randomised, blinded, placebo-controlled trial in 196 patients with CKD (eGFR: 20-40 mL/min/1.73 m2) and metabolic acidosis who were treated for up to 1 year with veverimer or placebo. We present the findings from a pre-specified subgroup analysis evaluating the effects of veverimer on metabolic acidosis and physical function among women (N = 77) enrolled in this trial. RESULTS: At week 52, women treated with veverimer had a greater increase in mean (± standard error) serum bicarbonate than the placebo group (5.4 [0.5] vs. 2.2 [0.6] mmol/L; P < 0.0001). Physical Function reported by patients on the Kidney Disease and Quality of Life - Physical Function Domain, a measure that includes items related to walking, stair climbing, carrying groceries and other activities improved significantly in women randomized to veverimer vs placebo (+ 13.2 vs. -5.2, respectively, P < 0.0031). Objectively measured performance time on the repeated chair stand test also improved significantly in the veverimer group vs. placebo (P = 0.0002). CONCLUSIONS: Veverimer was effective in treating metabolic acidosis in women with CKD, and significantly improved how they felt and functioned. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03390842 . Registered on January 4, 2018.

Serum electrolyte concentrations and skeletal muscle excitability in vivo.

OBJECTIVE: Multi-fibre muscle velocity recovery cycle (MVRC) assessment is a well-tolerated method of evaluating sarcolemmal excitability in vivo that shows promise as a research tool and biomarker. MVRC parameters correlate with venous electrolyte concentrations in myopathies. We sought to determine the nature of any such relationships in individuals without muscle disease. METHODS: Tibialis anterior MVRCs were recorded and electrolyte concentrations measured from two groups of healthy volunteers. After studying a single measure cohort (n = 65, one recording/person), we studied a repeated measures cohort (n = 4, eight recordings/person) to better study intra-individual relationships using repeated measures correlation (rmcorr). RESULTS: In the single measure cohort, no significant correlations were present between MVRC parameters and electrolyte levels after accounting for age. In the repeated measures cohort, the relative refractory period (P < 0.01) and stimulus frequency measures (P < 0.01) correlated positively with potassium levels. Multiple late supernormality group measures correlated negatively with bicarbonate levels (P < 0.01). CONCLUSIONS: MVRC measures that vary with the resting muscle membrane potential correlate with venous potassium concentrations, as in myopathies. Late supernormality measures correlate with bicarbonate levels. SIGNIFICANCE: Determination of serum electrolyte levels may inform the interpretation of MVRC study results if variation in concentrations is anticipated to be significant.

Utilization and Efficacy of Resuscitation Endpoints in Trauma and Burn Patients: A Review Article.

Shock is a sequelae in trauma and burn patients that substantially increases the risk for morbidity and mortality. The use of resuscitation endpoints allows for improved management of these patients, with the potential to prevent further morbidity/mortality. We conducted a review of the current literature on the efficacy of hemodynamic, metabolic, and regional resuscitation endpoints for use in trauma and burn patients. Hemodynamic endpoints included mean arterial pressure (MAP), heart rate (HR), urinary output (UO), compensatory reserve index (CRI), intrathoracic blood volume, and stroke volume variation (SVV). Metabolic endpoints measure cellular responses to decreased oxygen delivery and include serum lactic acid (LA), base deficit (BD), bicarbonate, anion gap, apparent strong ion difference, and serum pH. Mean arterial pressure, HR, UO, and LA are the most established markers of trauma and burn resuscitation. The evidence suggests LA is a superior metabolic endpoint marker. Newer resuscitation endpoint technologies such as point-of-care ultrasound (PoCUS), thromboelastography (TEG), and rotational thromboelastometry (ROTEM) may improve patient outcomes; however, additional research is needed to establish the efficacy in trauma and burn patients. The endpoints discussed have situational strengths and weaknesses and no single universal resuscitation endpoint has yet emerged. This review may increase knowledge and aid in guideline development. We recommend clinicians continue to integrate multiple endpoints with emphasis on MAP, HR, UO, LA, and BD. Future investigation should aim to standardize endpoints for each clinical presentation. The search for universal and novel resuscitation parameters in trauma and burns should also continue.

Metabolic acidosis in the initial 6 months after renal transplantation: A prospective study.

BACKGROUND: There is limited information about the incidence of metabolic acidosis (MA) after renal transplantation. This single centre prospective study aimed to delineate the incidence and risk factors of MA in the first 6 months after renal transplantation (RTX). DESIGN, SETTING, PARTICIPANTS AND MEASUREMENTS: Patients who underwent RTX between November 2018 and July 2020 were monitored with weekly measurement of serum bicarbonate level for 6 months and those who were diagnosed with MA were evaluated further to characterize the type of MA. RESULTS: One hundred and twenty-five patients were included in the study, 89 (71.2%) of whom developed MA. Seventy-two patients developed MA in the first month, 11 during the 2-3 months and 6 between 4 and 6 months after transplantation. Of the 89 patients, 55(61.8%) had type 1 renal tubular acidosis (T1RTA), 27 (30.3%) had type 2 RTA (T2RTA) and 7 (7.9%) type 4 RTA (T4RTA). Two patient who had T1RTA, subsequently developed high anion gap MA following severe graft rejection. On stepwise multivariate regression analysis, serum creatinine at time of diagnosis of MA [OR (95% CI): 12.02 (1.79 to 80.59), p = .01] and high tacrolimus C0 levels [OR (95% CI): 2.43 (1.0 to 5.90), p = .049], were independent risk factors for MA. CONCLUSION: There is a high incidence of MA in the initial 6 months post-transplant with serum creatinine and high tacrolimus C0 levels being independent risk factors.

The effect of type of fluid on disease severity in acute pancreatitis treatment.

OBJECTIVE: In this study, we aimed to investigate the effect of type of fluid (Normal Saline solution: NSS or Lactated Ringer's solution: LRS) to be selected in fluid replacement in acute pancreatitis (AP) treatment on disease severity. SUBJECTS AND METHODS: This study is a prospective, single-center study. Patients diagnosed with acute pancreatitis in emergency service were included in the study and randomized to receive LRS or NSS. The severity of AP was determined regarding Revised Atlanta Classification. C-reactive protein (CRP) levels and serum pH and bicarbonate (HCO3) levels were measured to evaluate the systemic inflammatory response and to detect changes in acid-base balance, respectively. RESULTS: Sixty-five and seventy-seven patients receiving NSS and LRS, respectively, were analyzed. Eighty-nine (67.4%) and 43 (32.6%) patients were with mild and moderate AP, respectively; however, there was no patient with severe AP. The frequency of moderate AP was significantly lower in the LRS group than the NSS group in terms of the severity of AP (p=0.011). Subjects that were randomized to receive LRS had lower CRP levels when compared to the participants in the NSS treatment arm 48 hours after resuscitation (p=0.010). In addition to these results, serum pH and HCO3 level in patients resuscitated with NSS reduced in comparison to LRS (p<0.001). CONCLUSIONS: Resuscitation with LRS is associated with decreased severity of AP in patients with AP. It may derive from how it causes lower CRP levels.