Metabolic acidosis in pediatric kidney transplant recipients.

BACKGROUND: Metabolic acidosis is a risk factor for faster kidney function decline in chronic kidney disease (CKD) and in adult kidney transplant recipients (KTRs). We hypothesized that metabolic acidosis would be highly prevalent and associated with worse allograft function in pediatric KTRs. METHODS: Pediatric KTRs at Montefiore Medical Center from 2010 to 2018 were included. Metabolic acidosis was defined as serum bicarbonate < 22 mEq/L or receiving alkali therapy. Regression models were adjusted for demographic factors and donor/recipient characteristics. RESULTS: Sixty-three patients were identified with a median age at transplant of 10.5 (interquartile range (IQR) 4.4-15.2) years and post-transplant follow-up of 3 (IQR 1-5) years. Baseline serum bicarbonate was 21.7 ± 2.4 mEq/L, serum bicarbonate < 22 mEq/L was present in 28 (44%), and 44% of all patients were receiving alkali therapy. The prevalence of acidosis ranged from 58 to 70% during the first year of follow-up. At baseline, each 1-year higher age at transplant and every 10 ml/min/1.73 m2 higher eGFR were associated with 0.16 mEq/L (95% CI: 0.03-0.3) and 0.24 mEq/L (95% CI: 0.01-0.5) higher serum bicarbonate, respectively. Older age at transplant was associated with lower odds of acidosis (OR: 0.84; 95% CI: 0.72-0.97). During follow-up, metabolic acidosis was independently associated with 8.2 ml/min/1.73 m2 (95% CI 4.4-12) lower eGFR compared to not having acidosis; furthermore, eGFR was significantly lower among KTRs with unresolved acidosis compared with resolved acidosis. CONCLUSIONS: Among pediatric KTRs, metabolic acidosis was highly prevalent in the first year post-transplantation and was associated with lower eGFR during follow-up. A higher resolution version of the Graphical abstract is available as Supplementary information.

Prevalence of metabolic acidosis in ileal diversions more than one year after radical cystectomy and associated secondary metabolic effects.

INTRODUCTION AND OBJECTIVE: Metabolic acidosis (MA) is a well-known complication in patients with ileal urinary diversions. It is common in the early postoperative stages and decreases over time. Our objective is to investigate the prevalence of MA after more than one year of follow-up, identify the associated risk factors, and analyze its secondary metabolic consequences. MATERIALS AND METHODS: We conducted an observational study between January 2018 and September 2022 following the STROBE guidelines. MA was defined as a serum bicarbonate level ​​<22mEq/L. Finally, we analyzed 133 patients with a mean follow-up of 55.24 ± 42.36 months. RESULTS: MA was observed in 16 (12%) patients. Patients with and without MA were comparable in age, sex, and follow-up time. The group with MA presented a higher rate of anemia (68,75% vs 19,65%, p < 0.001) and renal failure (100% vs 45,29%, p < 0.001), statistically significant higher levels of serum creatinine, chloride, potassium, parathyroid hormone, and phosphorus but lower serum values ​​of hemoglobin, renal glomerular filtration rate, total cholesterol, vitamin D, calcium, and albumin (all p < 0.05). Renal glomerular filtration rate was the only independent risk factor related to the development of MA (OR 0.914; 95% CI 0.878-0.95; p < 0.0001), proving a close correlation with venous bicarbonate values ​​(r = 0.387, p < 0.001). CONCLUSIONS: MA is a little prevalent disorder in ileal urinary diversions more than one year after radical cystectomy is performed but it has secondary consequences on hematologic, renal, protein, lipid, and bone metabolism. We recommend to a close follow-up in patients with renal failure for early diagnosis and treatment.

Multi-organ dysfunction in infants with acidosis at birth in the absence of moderate to severe hypoxic ischemic encephalopathy.

INTRODUCTION: Infants with perinatal asphyxia are at risk for organ failure aside from the brain, regardless of the severity of the asphyxial insult. We aimed to evaluate the presence of organ dysfunction other than the brain in newborns with moderate to severe acidosis at birth, in the absence of moderate to severe hypoxic ischemic encephalopathy. MATERIALS AND METHODS: Data of 2 years were retrospectively recorded. Late preterm and term infants admitted to the intensive care unit with ph < 7.10 and BE < -12 mmol/l in the first hour were included in the absence of moderate to severe hypoxic ischemic encephalopathy. Respiratory dysfunction, hepatic dysfunction, renal dysfunction, myocardial depression, gastrointestinal problems, hematologic system dysfunction, and circulatory failure were evaluated. RESULTS: Sixty-five infants were included [39 (37-40) weeks, 3040 (2655-3380) grams]. Fifty-six (86 %) infants had one or more dysfunction in any system [respiratory: 76.9 %, hepatic: 20.0 %, coagulation: 18.5 %, renal: 9.2 %, hematologic: 7.7 %, gastrointestinal: 3.0 %, and cardiac: 3.0 %]. Twenty infants had at least two affected systems. The incidence of coagulation dysfunctions was higher in the infants with severe acidosis (n = 25, ph < 7.00) than the infants with moderate acidosis (n = 40: pH = 7.00-7.10); 32 % vs 10 %; p = 0.03. CONCLUSIONS: Moderate to severe fetal acidosis is associated with the development of extra-cranial organ dysfunctions in infants who do not require therapeutic hypothermia. A monitoring protocol is needed for infants with mild asphyxia in order to identify and manage potential complications. Coagulation system should be carefully evaluated.

High risk and low prevalence diseases: Toxic alcohol ingestion.

INTRODUCTION: Toxic alcohol ingestion is a rare but serious condition that carries with it a high rate of morbidity and mortality. OBJECTIVE: This review highlights the pearls and pitfalls of toxic alcohol ingestion, including presentation, diagnosis, and management in the emergency department (ED) based on current evidence. DISCUSSION: Toxic alcohols include ethylene glycol, methanol, isopropyl alcohol, propylene glycol, and diethylene glycol. These substances can be found in several settings including hospitals, hardware stores, and the household, and ingestion can be accidental or intentional. Toxic alcohol ingestion presents with various degrees of inebriation, acidemia, and end-organ damage depending on the substance. Timely diagnosis is critical to prevent irreversible organ damage or death and is based primarily on clinical history and consideration of this entity. Laboratory evidence of toxic alcohol ingestion includes worsening osmolar gap or anion-gap acidemia and end organ injury. Treatment depends on the ingestion and severity of illness but includes alcohol dehydrogenase blockade with fomepizole or ethanol and special considerations for the initiation of hemodialysis. CONCLUSIONS: An understanding of toxic alcohol ingestion can assist emergency clinicians in diagnosing and managing this potentially deadly disease.

Effects of topiramate therapy on serum bicarbonate concentration in a sample of 10,279 veterans.

BACKGROUND: Topiramate, which is increasingly being used to treat alcohol use disorder (AUD), is commonly associated with reduced serum bicarbonate concentrations. However, estimates of the prevalence and magnitude of this effect are from small samples and do not address whether topiramate's effects on acid-base balance differ in the presence of an AUD or by topiramate dosage. METHODS: Veterans Health Administration electronic health record (EHR) data were used to identify patients with a minimum of 180 days of topiramate prescription for any indication and a propensity score-matched control group. We differentiated patients into two subgroups based on the presence of a diagnosis of AUD in the EHR. Baseline alcohol consumption was determined using Alcohol Use Disorders Identification Test-Consumption (AUDIT-C) scores in the EHR. Analysis also included a three-level measure representing mean daily dosage. The topiramate-associated changes in serum bicarbonate concentration were estimated in difference-in-differences linear regression models. A serum bicarbonate concentration <17 mEq/L was considered to represent possible clinically significant metabolic acidosis. RESULTS: The cohort comprised 4287 topiramate-treated patients and 5992 propensity score-matched controls with a mean follow-up period of 417 days. The mean topiramate-associated reductions in serum bicarbonate concentration were <2 mEq/L in the low (≤88.75), medium (>88.75 and ≤141.70), and high (>141.70) mg/day dosage tertiles, irrespective of AUD history. Concentrations <17 mEq/L occurred in 1.1% of topiramate-treated patients and 0.3% of controls and were not associated with alcohol consumption or an AUD diagnosis. CONCLUSIONS: The excess prevalence of metabolic acidosis associated with topiramate treatment does not differ with dosage, alcohol consumption, or the presence of an AUD. Baseline and periodic serum bicarbonate concentration measurements are recommended during topiramate therapy. Patients prescribed topiramate should be educated about the symptoms of metabolic acidosis and urged to report their occurrence promptly to a healthcare provider.

The cumulative incidence of neonatal metabolic acidemia after terminal bradycardia in the 2nd stage of labor: a survival-based model.

PURPOSE: The aim of the study was to estimate by a survival analysis model the hazard function (HF) for neonatal metabolic acidemia (MA) throughout the 2nd stage of labor (2STG) at the time of occurrence of a terminal bradycardia ≥ 10 min requiring expedited delivery, and the cumulative incidence function (CIF) for MA according with the duration of bradycardia stratified in 10-12 min and > 12 min. METHODS: Singleton pregnancies experiencing terminal fetal bradycardia requiring expedited delivery in the 2STG at 38 + 0-41 + 3 weeks and delivering in the year 2019, were identified. The presence of MA (pH < 7 and/or BE ≤ - 12 mmol/L) was determined based on the acid-base status in the umbilical artery cord blood. Survival analysis was used to assess the hazard function (HF) and the cumulative incidence function (CIF) for MA occurring after terminal fetal bradycardia, at the 2STG. RESULTS: Out of a non-consecutive population of 12,331 pregnancies, there were 52 cases that fit the inclusion criteria. Twenty-four (46.2%) of those develop MA. Abnormal quantitative pH values and the HF for MA correlated with the duration of 2STG at the time of bradycardia onset, but not with bradycardia duration. After 60 min of duration of 2STG, the HF (or instantaneous rate of failure) increased dramatically (from 1.2 to 20 about at 120 min). At paired duration of 2STG, a higher CIF was observed for the terminal bradycardia > 12 min. CONCLUSION: Forty-six percent of term fetuses with terminal bradycardia had MA at birth. Despite the low sensitivity and a non-significant association with quantitative pH values, the duration of terminal bradycardia in the 2STG is associated with a higher CIF for MA.

Mass Poisoning From Ethylene Glycol at a U.S. Military Base.

Ethylene glycol (EG) toxicity is an important cause of toxic alcohol poisoning in the USA with over 5,000 exposures reported annually. While classically characterized by solitary accidental or intentional ingestions, mass toxic alcohol poisoning outbreaks and more rarely collective consumptions (typically of methanol) have been described. We describe an ethylene glycol poisoning from collective ingestion that involved soldiers presenting at William Beaumont Army Medical Center in El Paso, Texas. Eleven soldiers presented to the emergency department over a 12-h period after ingestion of an unknown substance. The first two patients exhibited severe neurologic symptoms, while the remainder were asymptomatic. As serum EG levels were not immediately available, treatment decisions were based on surrogate laboratory values. Two patients received immediate hemodialysis, and fomepizole (FOM) because of severe acidosis with elevated anion and osmolal gaps. These patients developed acute kidney injury with renal recovery within a 3-week period. Two patients with elevated lactate received bicarbonate-based intravenous (IV) fluids and FOM. Two patients received IV fluids only and required prolonged observation for worsening acidosis and/or acute kidney injury. Five patients with normal laboratory values were treated with IV fluids and observation. All patients received cofactors including thiamine and pyridoxine. All patients survived. The outbreak occurred in the setting of limited dialysis resources, limited FOM availability, and in a resource-limited community. Additional guidelines are needed to determine allocation of limited resources, optimal dialysis and FOM treatment course, and comorbid conditions, which may prolong recovery.

Metabolic acidosis after ileal urinary diversion and radical cystectomy. Do we know as much as we think we do? A systematic review.

Urine contact with the mucosa of the urinary diversion (UD) after radical cystectomy (RC) produces different ion exchanges that favor the development of metabolic acidosis (MA). This phenomenon is a frequent cause of hospital readmission and short/long-term complications. We performed a systematic review of MA in RCs with ileal UD, analyzing its prevalence, diagnosis, risk factors and treatment. We systematically searched Pubmed® and Cochrane Library for original articles published before May 2022 according to PRISMA guidelines. A total of 421 articles were identified. We selected 25 studies that met the inclusion criteria involving 5811 patients. Obtaining precise data on the prevalence of MA is difficult, largely due to the heterogeneity of the diagnostic criteria used given the diversity of studies analyzed. Development of MA is multifactorial. In the early period, MA is more prevalent in patients with UD with longer ileal segments, better urinary continence, and impaired renal function. Age and diabetes are risk factors associated with MA in later periods. MA is the most common cause of second or more hospital readmissions. Prophylaxis with oral bicarbonate for three months in patients at risk could improve these results. Although MA after ileal UD is a well-known condition, this review highlights the need to implement homogeneous criteria for the diagnosis, follow-up, and treatment, in addition to protocolizing prevention/prophylaxis strategies in patients at risk.

Metabolic acidosis is undertreated and underdiagnosed: a retrospective cohort study.

BACKGROUND: Guidelines recommend treatment of metabolic acidosis (MA) in patients with chronic kidney disease (CKD), but the diagnosis and treatment rates in real-world settings are unknown. We investigated the frequency of MA treatment and diagnosis in patients with CKD. METHODS: In this retrospective cohort study, we examined administrative health data from two US databases [Optum's de-identified Integrated Claims + Clinical Electronic Health Record Database (US EMR cohort; 1 January 2007 to 30 June 2019) and Symphony Health Solutions IDV® (US claims cohort; 1 May 2016 to 30 April 2019)] and population-level databases from Manitoba, Canada (1 April 2006 to 31 March 2018). Patients who met laboratory criteria indicative of CKD and chronic MA were included: two consecutive estimated glomerular filtration results <60 mL/min/1.73 m2 and two serum bicarbonate results 12 to <22 mEq/L over 28-365 days. Outcomes included treatment of MA (defined as a prescription for oral sodium bicarbonate) and a diagnosis of MA (defined using administrative records). Outcomes were assessed over a 3-year period (1 year pre-index, 2 years post-index). RESULTS: A total of 96 184 patients were included: US EMR, 6179; Manitoba, 3223; US Claims, 86 782. Sodium bicarbonate treatment was prescribed for 17.6%, 8.7% and 15.3% of patients, and a diagnosis was found for 44.7%, 20.9% and 20.9% of patients, for the US EMR, Manitoba and US Claims cohorts, respectively. CONCLUSIONS: This analysis of 96 184 patients with laboratory-confirmed MA from three independent cohorts of patients with CKD and MA highlights an important diagnosis and treatment gap for this disease-modifying complication.

Acute methanol poisoning in Tunisia: clinical features, biological and associated factors for mortality.

BACKGROUND: Acute Methanol Poisoning (MP) is rare but potentially serious. OBJECTIVES: To study the clinical and biological characteristics of acute MP and its associated factors of mortality. METHODS: We conducted a cross-sectional study including case series of MP which took place in Kairouan, Tunisia. Cases started consulting the emergency room on a festive day (1st day of Eid al- Fitr) corresponding to May 24, 2020. RESULTS: We included 65 male victims of MP. The median [interquartile] age was 28.0 [21.0 - 35.0] years with extremes ranging from 17 to 75 years. The median [interquartile] time between the ingestion of methanol and the medical consultation was 48.0 [24.0 - 50.0] hours. On admission, the majority of patients described neurological (98.4%) and gastrointestinal symptoms (51.4%). Four patients remained visually impaired and 8 patients (12.3%) had died. The univariate analysis reported an association between mortality and age, amount of methanol ingested, co-ingestion of cannabis, delay to consultation, neurological distress, seizures, lower systolic and diastolic blood pressure, metabolic acidosis, lower levels of potassium, higher levels of sodium, hematocrit, glycemia, creatinine, anion gap, and high Acute Physiology and Chronic Health Evaluation II score. CONCLUSION: Mortality rate following MP was high and was associated with several factors.

Association of labour duration in spontaneous deliveries with low neonatal Apgar scores and foetal acidosis: the Japan Environment and Children's Study.

This study evaluated the association between labour duration (LD) and incidence of low neonatal Apgar scores and foetal acidosis. Data of 37,682 women with full-term singleton spontaneous vaginal deliveries from the Japan Environment and Children's Study were analysed. Women were classified according to the median LD as nulliparous (< 10 or ≥ 10 h) or multiparous (< 5 or ≥ 5 h) and further into five subcategories: nulliparous (< 10.0, 10.0-12.9, 13.0-15.9, 16.0-18.9, and ≥ 19 h) and multiparous (< 5.0, 5.0-7.9, 8.0-10.9, 11.0-13.9, and ≥ 14.0 h). Multiple logistic regression models were used to determine odds ratios (ORs) for outcomes in women with over-median LD. Over-median LD exhibited no statistically significant association with low neonatal Apgar scores. The adjusted ORs for both umbilical artery (UmA-pH) < 7.2 and < 7.1 were increased in nulliparous women with over-median LD, whereas only the adjusted OR for UmA-pH < 7.2 was increased in multiparous women with over-median LD. Moreover, this association manifested as a plateau in nulliparous women with LD ≥ 13 h and without dose-dependent association in multiparous women.

Associations of Metabolic Syndrome and Abdominal Obesity with Anion Gap Metabolic Acidosis among US Adults.

Background: Obesity is a recently identified risk factor for metabolic acidosis and anion gap elevations in the absence of CKD. Metabolic acidosis is a treatable condition with substantial adverse effects on human health. Additional investigations are needed to characterize at-risk populations and explore potential mechanisms. We hypothesized metabolic syndrome (MetS) and waist circumference (WC) would be closely associated with this pathology. Methods: Adult participants from NHANES 1999-2018 meeting study criteria were compiled as main (n=31,163) and fasting (n=12,860) cohorts. Regression models adjusted for dietary acid, eGFR, and other factors examined associations of WC and MetS features with anion gap metabolic acidosis and its components (serum bicarbonate ≤23 mEq/L and anion gap >95th percentile). Results: Greater WC and MetS features were associated with progressively lower bicarbonate, higher anion gap, and greater odds ratios (OR) of metabolic acidosis (MA) and anion gap metabolic acidosis (AGMA). Compared with the reference, participants with the highest WC had ORs for MA and AGMA of 2.26; 95% CI, 1.96 to 2.62 and 2.89; 95% CI, 1.97 to 4.21; those with three and four versus zero MetS features had ORs for AGMA of 2.52; 95% CI, 1.95 to 2.94 and 3.05; 95% CI, 2.16 to 3.82. Associations of body mass index with outcomes were attenuated or absent after adjustment for WC or MetS. Findings were preserved after excluding eGFR <90 ml/min per 1.73 m2 and albuminuria. A lower MA cutoff (<22 mEq/L) raised the estimate of association between MetS and MA (OR for three and four vs zero features: 3.56; 95% CI, 2.53 to 5.02 and 5.44; 95% CI, 3.66 to 8.08). Conclusions: Metabolic diseases are characterized by metabolic acidosis and anion gap elevations. Metabolic dysfunction may predispose patients without CKD to systemic acidosis from endogenous sources. Comprehensive acid-base analyses may be informative in patients with metabolic diseases.

Association Between Obesity and Fetal Acidosis at Scheduled Cesarean Delivery.

OBJECTIVE: To evaluate whether patients with obesity who undergo scheduled cesarean delivery under neuraxial anesthesia are at increased risk for umbilical artery pH less than 7.1 and base deficit 12 mmol or greater. METHODS: We conducted a multicenter, retrospective cohort study of individuals who delivered a term, singleton, nonanomalous neonate at one of four academic medical centers in New York City from 2013 to 2019 by scheduled cesarean under neuraxial anesthesia for whom fetal cord blood gas results were available. The primary study outcome was rate of fetal acidosis , defined as umbilical artery pH less than 7.1. This was compared between patients with obesity (body mass index [BMI] 30 or higher) and those without obesity (BMI lower than 30). Base deficit 12 mmol or greater and a composite of fetal acidosis and base deficit 12 mmol or greater were also compared. Secondary outcomes included neonatal intensive care unit admission rate, 5-minute Apgar score less than 7, and neonatal morbidity. Associations between maternal BMI and study outcomes were assessed using multivariable logistic or linear regression and adjusted for age, race and ethnicity, insurance type, cesarean delivery order number, and neuraxial anesthesia type. RESULTS: Of the 6,264 individuals who met inclusion criteria during the study interval, 3,098 had obesity and 3,166 did not. The overall rate of umbilical artery cord pH less than 7.1 was 2.5%, and the overall rate of umbilical artery base deficit 12 mmol or greater was 1.5%. Patients with obesity were more likely to have umbilical artery cord pH less than 7.1 (adjusted odds ratio [aOR] 2.7, 95% CI 1.8-4.2) and umbilical artery base deficit 12 mmol or greater (aOR 3.2, 95% CI 1.9-5.3). This association was not significantly attenuated after additional adjustments for potential mediators, including maternal medical comorbidities. We found no differences in secondary outcomes between groups. CONCLUSION: Maternal obesity is associated with increased odds of arterial pH less than 7.1 and base deficit 12 mmol or greater at the time of scheduled cesarean delivery under neuraxial anesthesia.

Hyperkalemia and Metabolic Acidosis Occur at a Higher eGFR in Sickle Cell Disease.

Background: People with sickle cell disease (SCD) have an elevated estimated glomerular filtration rate (eGFR) compared with the general population, and this may alter the usual creatinine-based eGFR cutoffs for which physiologic evidence of kidney dysfunction is apparent. This study aimed to identify eGFR thresholds for hyperkalemia and metabolic acidosis in patients with SCD. Methods: This was a cross-sectional analysis of 733 patients with severe (hemoglobin SS or Sß0-thalassemia) SCD genotype, 238 patients with moderate (hemoglobin SC or Sß+-thalassemia) SCD genotype, and 1333 age- and sex-matched African Americans from the National Health and Nutrition Examination Survey (NHANES). The prevalence rates of hyperkalemia and metabolic acidosis were compared by eGFR category. Cutoffs for hyperkalemia and metabolic acidosis were determined using generalized additive models. Results: Hyperkalemia and metabolic acidosis were more common in those with severe SCD genotype (13% and 21%, respectively) compared with the NHANES (0.3% and 5%, respectively); the prevalence rates in the moderate SCD genotype were intermediate for hyperkalemia (3%) and metabolic acidosis (11%). The proportion of patients with hyperkalemia and metabolic acidosis progressively increased with lower eGFR category in both SCD genotype groups. The eGFR thresholds for hyperkalemia and metabolic acidosis were higher in the severe (85 and 91 ml/min per 1.73 m2, respectively) and moderate (52 and 102 ml/min per 1.73 m2, respectively) SCD genotypes compared with the NHANES (34 and 46 ml/min per 1.73 m2). Conclusions: We demonstrate that hyperkalemia and metabolic acidosis are more common and occur at higher eGFR values in patients with SCD compared with age- and sex-matched African Americans, including in eGFR ranges considered to be normal. Future studies using redefined creatinine-based eGFR thresholds for abnormal kidney function may identify high-risk patients for earlier intervention strategies and referral for specialized renal care in SCD.

The association of fetal acidemia with adverse neonatal outcomes at time of scheduled cesarean delivery.

BACKGROUND: Fetal acidemia at the time of a scheduled cesarean delivery is generally unexpected. In the setting of reassuring preoperative monitoring, the duration of fetal acidemia in this scenario is presumably brief. The neonatal sequelae and risks associated with brief fetal acidemia in this setting are unknown. OBJECTIVE: We aimed to assess whether fetal acidemia at the time of a scheduled prelabor cesarean delivery is associated with adverse neonatal outcomes. STUDY DESIGN: This was a retrospective cohort study of singleton, term, nonanomalous, liveborn neonates delivered by scheduled cesarean delivery that was performed under regional anesthesia from 2004 to 2014 at a single tertiary care center with a universal umbilical cord gas policy. Neonates born to laboring gravidas and those whose cesarean delivery was performed for nonreassuring fetal status were excluded. All included patients had reassuring preoperative fetal monitoring. The primary outcome was a composite adverse neonatal outcome that included neonatal death, encephalopathy, therapeutic hypothermia, seizures, intubation, and respiratory distress. This outcome was compared between patients with and those without fetal acidemia (umbilical artery pH <7.2). A multivariable logistic regression was used to adjust for confounders. Cases of fetal acidemia were further characterized as respiratory, metabolic, or mixed acidemia based on additional umbilical cord gas values. Secondary analyses examining the association between the type of acidemia and neonatal outcomes were also performed. RESULTS: Of 2081 neonates delivered via scheduled cesarean delivery, 252 (12.1%) had fetal acidemia at the time of delivery. Acidemia was more common in breech neonates and in neonates born to gravidas with obesity and gestational diabetes mellitus. Compared with fetuses with normal umbilical artery pH, those with fetal acidemia were at a significantly increased risk for adverse neonatal outcome (adjusted relative risk, 2.95; 95% confidence interval, 2.03-4.12). This increased risk was similar regardless of the type of acidemia. CONCLUSION: Even a brief period of mild acidemia is associated with adverse neonatal outcomes at the time of a scheduled cesarean delivery despite reassuring preoperative monitoring. Addressing modifiable intraoperative factors that may contribute to fetal acidemia at the time of a scheduled cesarean delivery, such as maternal hypotension and prolonged operative time, is an important priority to potentially decrease neonatal morbidity in full-term gestations.

Risk factors for hypoxic-ischemic encephalopathy in cases of severe acidosis: A case-control study.

INTRODUCTION: The aim of the study was to identify the obstetric risk factors for hypoxic-ischemic encephalopathy (HIE) in infants with asphyxia at birth. MATERIAL AND METHODS: This multicenter case-control study covered the 5-year period from 2014 through 2018 and included newborns ≥36 weeks of gestation with an umbilical pH at birth ≤7.0. Cases were newborns who developed moderate or severe HIE; they were matched with controls with pH ≤7.0 at birth over the same period without moderate or severe HIE. The factors studied were maternal, gestational, intrapartum, delivery-related, and neonatal characteristics. A multivariable analysis was performed to study the maternal, obstetric, and neonatal factors independently associated with moderate or severe HIE. RESULTS: Our review of the records identified 41 cases and 98 controls. Compared with controls, children with moderate or severe HIE had a lower 5-min Apgar score, lower umbilical artery pH, and higher cord lactate levels at birth and at 1 h of life. Obstetric factors associated with moderate or severe HIE were the occurrence of an acute event (adjusted odds ratio [aOR] 6.4; 95% confidence interval [CI] 1.8-22.5), maternal fever (aOR 3.5; 95% CI 1.0-11.9), and thick meconium during labor (aOR 2.9; 95% CI 1.0-8.6). CONCLUSIONS: HIE is associated with a lower 5-min Apgar score and with the severity of acidosis at birth and at 1 h of life. In newborns with a pH <7.0 at birth, the occurrence of an acute obstetric event, maternal fever, and thick meconium are independent factors associated with moderate or severe HIE.

Impact of interval between induction of spinal anesthesia to delivery on umbilical arterial cord ph of neonates delivered by elective cesarean section.

BACKGROUND: To evaluate the impact of interval between induction of spinal anesthesia to delivery of the fetus by elective cesarean section on umbilical arterial pH and neonatal outcome. PATIENTS AND METHODS: Two hundred and twenty pregnant women who were planned for elective cesarean section at term under spinal anesthesia were recruited. Minimum systolic, diastolic and mean arterial blood pressures (SBP, DBP, MAP) and largest pressure decrease (SBP, DBP, MPA) were also recorded. Induction of spinal anesthesia to delivery interval was measured. Following delivery, umbilical arterial cord analysis for pH and base deficit were done. Apgar scores at 1 min and at 5 min, neonatal intensive care unit (NICU) admission, need for mechanical ventilation and incidence of hypoxemic-ischemic encephalopathy were recorded. RESULTS: Induction of spinal anesthesia to delivery interval was 25.7 ± 5.6 min. Lowest SBP and MAP reached during cesarean delivery were 88.9 ± 7.3 mmHg and 60.4 ± 5.6 mmHg, respectively. MAP < 65 mmHg was reached in 136 (62%) patients with a decrease of MAP of > 20% in 149 (68%) patients. Duration of the longest hypotension episode was 3.3 ± 2.2 min. All patients required ephedrine administration for hypotensive episodes with an average dosage of 11.4 ± 3.2 mg. Umbilical pH of 7.3 ± 0.1 and base deficit of 8.3 ± 4.4 mmol/l were recorded. Apgar scores at 5 min were 8.5 ± 1.2. Eight (3.6%) neonates were admitted in the NICU. One neonate needed mechanical ventilation. There were no cases of hypoxemic-ischemic encephalopathy. There were inverse correlations between induction of spinal anesthesia to delivery interval, body mass index (BMI) and duration of longest hypotension episode in relation to umbilical pH (r = -0.817, -0.395 and -0.268, respectively). Cut off value for induction of spinal anesthesia to delivery interval greater than 27 min predicted an umbilical pH of < 7.2. Cut off value for the duration of the longest hypotension episode greater than 5 min predicted an umbilical pH of < 7.2. Cut off value for BMI greater than 35 kg/m2 predicted an umbilical pH of < 7.2. CONCLUSION: Prolonged interval between induction of spinal anesthesia to delivery could be associated with neonatal acidosis. This could be aggravated by maternal obesity and prolonged duration of hypotension episodes during cesarean delivery.

Electrolyte and Acid-Base Disturbances in Emergency High-Risk Abdominal Surgery, a Retrospective Study.

BACKGROUND: Patients undergoing emergency high-risk abdominal surgery potentially suffer from both systemic dehydration and hypovolaemia. Data on the prevalence and clinical impact of electrolyte disturbances in this patient group, specifically the differences in patients with intestinal obstruction (IO) versus perforated viscus (PV) are lacking. METHODS: Adult patients undergoing emergency high-risk abdominal surgery in a standardized perioperative pathway were included in this retrospective single-center cohort study. Electrolytes and arterial blood gas analysis were measured during the early perioperative period. Prevalence and clinical impact of electrolyte disturbances were assessed. RESULTS: A total of 354 patients were included in the study. Preoperative alkalemia dominated preoperatively, significantly more prevalent in IO (45 vs. 32%, p < .001), while acidosis was most pronounced postoperatively in PV (49 vs. 28%, p < .0001). Preoperative hypochloraemia and hypokalemia were more frequent in the IO (34 vs. 20% and 37 vs. 25%, respectively). Hyponatremia was highly prevalent in both IO and PV. Pre- and postoperative hypochloremia were independently associated with 30-day postoperative morbidity and mortality in patients with IO (OR 2.87 (1.35, 6.23) p = 0.006, OR 6.86 (1.71, 32.2) p = 0.009, respectively). Hypochloremic patients presented with reduced long-term survival as compared with the normo- and hyperchloremic patients (p < 0.05). Neither plasma sodium nor potassium showed a significant association with outcome. CONCLUSION: These observations suggest that acute high-risk abdominal patients have frequent preoperative alkalosis shifting to postoperative acidosis. Both pre- and postoperative hypochloremia were independently associated with both impaired short- and long-term outcome in patients with intestinal obstruction, with potential implications for the choice of resuscitations fluids.

Short-term morbidity and types of intrapartum hypoxia in the newborn with metabolic acidaemia: a retrospective cohort study.

OBJECTIVES: To assess labour characteristics in relation to the occurrence of Composite Adverse neonatal Outcome (CAO) within a cohort of fetuses with metabolic acidaemia. DESIGN: Retrospective cohort study. SETTING: Three Italian tertiary maternity units. POPULATION: 431 neonates born with acidaemia ≥36 weeks. METHODS: Intrapartum CTG traces were assigned to one of these four types of labour hypoxia: acute, subacute, gradually evolving and chronic hypoxia. The presence of CAO was defined by the occurrence of at least one of the following: Sarnat Score grade ≥2, seizures, hypothermia and death <7 days from birth. MAIN OUTCOME MEASURES: To compare the type of hypoxia on the intrapartum CTG traces among the acidaemic neonates with and without CAO. RESULTS: The occurrence of a CAO was recorded in 15.1% of neonates. At logistic regression analysis, the duration of the hypoxia was the only parameter associated with CAO in the case of an acute or subacute pattern (odds ratio [OR] 1.3; 95% CI 1.02-1.6 and OR 1.04; 95% CI 1.0-1.1, respectively), whereas both the duration of the hypoxic insult and the time from PROM to delivery were associated with CAO in those with a gradually evolving pattern (OR 1.13; 95% CI 1.01-1.3 and OR 1.04; 95% CI 1.0-1.7, respectively). The incidence of CAO was higher in fetuses with chronic antepartum hypoxia than in those showing CTG features of intrapartum hypoxia (64.7 vs. 13.0%; P < 0.001). CONCLUSIONS: The frequency of CAO seems related to the duration and the type of the hypoxic injury, being higher in fetuses showing CTG features of antepartum chronic hypoxia. TWEETABLE ABSTRACT: This study demonstrates that in a large population of neonates with metabolic acidaemia at birth, the overall incidence of short-term adverse outcome is around 15%. Such risk seems closely correlated to the duration and the type of hypoxic injury, being higher in fetuses admitted in labour with antepartum chronic hypoxia than those experiencing intrapartum hypoxia.

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 ).