Antiseizure Medication use in Gastric Bypass Patients and Other Post-Surgical Malabsorptive States.

Healthcare professionals are encountering an increasing number of patients who have undergone bariatric surgeries. Antiseizure medications (ASM) have a narrow therapeutic window, and patients with malabsorptive states receiving ASM present a complex situation as the pharmacokinetics of these drugs have only been studied in patients with a normal functioning gastrointestinal tract. Patients with malabsorptive states may have altered pharmacokinetics, and there is limited literature to guide drug selection and dosage adjustment in patients with malabsorptive states. This review highlights pharmacokinetic parameters of common ASM, and considerations when managing patients on them. The effect of pH, lipophilicity, absorption, and metabolism should be taken into account when selecting and managing ASMs in this patient population. Based on these parameters, levetiracetam, and topiramate have fewer issues referable to absorption related to bariatric surgery while oral formulations of phenytoin, carbamazepine, oxcarbamazepine and valproic acid have reduced absorption due to effects of bariatric surgery based on the pharmacokinetic properties of these medications. Extended formulations should be avoided and ASM serum concentrations should be checked before and after surgery. The care of patients with epilepsy who are scheduled to undergo bariatric surgery should be guided by a multidisciplinary team including a pharmacist and a neurologist who should be involved in the adjustment of the ASMs throughout the pre-surgical and post-surgical periods.

Sarcopenia Index Is a Simple Objective Screening Tool for Malnutrition in the Critically Ill.

BACKGROUND: Reliable and valid tools to screen for malnutrition in the intensive care unit (ICU) remain elusive. The sarcopenia index (SI) [(serum creatinine/serum cystatin C) × 100], could be an inexpensive, objective tool to predict malnutrition. We evaluated the SI as a screening tool for malnutrition in the ICU and compared it with the modified-NUTRIC score. MATERIALS AND METHODS: This was a historical cohort study of ICU patients with stable kidney function admitted to Mayo Clinic ICUs between 2008 and 2015. Malnutrition was defined by the Subjective Global Assessment. Diagnostic performance was evaluated with the area under the receiver operating characteristic curve (AUC) and multivariable logistic regression. RESULTS: Of the 398 included patients, 181 (45%) had malnutrition, with 34 (9%) scored as severely malnourished. The SI was significantly lower in malnourished patients than in well-nourished patients (64 ± 27 vs 72 ± 25; P = 0.002), and reductions in SI corresponded to increased malnutrition severity (P = 0.001). As a screening tool, the SI was an indicator of malnutrition risk (AUC 0.61) and performed slightly better than the more complex modified-NUTRIC score (AUC = 0.57). SI cutoffs of 101 and 43 had >90% sensitivity and >90% specificity, respectively, for the prediction of malnutrition. Patients with a low SI (≤43) had a significantly higher risk of mortality (HR = 2.61, 95% CI 1.06-6.48, P = 0.038). CONCLUSION: The frequency of malnutrition was high in this critically ill population, and it was associated with a poor prognosis. The SI could be used to assess nutrition risk in ICU patients.

Validation of the sarcopenia index to assess muscle mass in the critically ill: A novel application of kidney function markers.

BACKGROUND & AIMS: Adverse outcomes for hospitalized patients with sarcopenia are well documented, and identification of patients at risk remains challenging. The sarcopenia index (SI), previously defined as (serum creatinine/serum cystatin C) × 100, could be an inexpensive, readily accessible, objective tool to predict muscle mass and risk for adverse clinical outcomes. The aim of this study was to assess the validity of the SI as a predictor of muscle mass. METHODS: Retrospective study of critically ill adults admitted to Mayo Clinic from 2012 to 2015 with suspected sepsis and an available creatinine and serum cystatin C. Muscle surface area was quantified at the L3/4 vertebral level in patients with an abdominal CT scan (CTMSA). Multivariable regression modeling was used to assess the relationship between SI and CTMSA, as well as short-term clinical outcomes. RESULTS: The 171 included had a mean weight and body mass index (BMI) of 75.2 ± 16.4 kg and 26.0 ± 4.6 kg/m2 and abdominal CT scans were available for 81 (47%) patients. The SI correlated with CTMSA (r = 0.40). After adjustment for age, sex, severity of illness, and BMI, SI was independently associated with muscle mass (P = 0.001). A decrease in the SI (indicative of lower muscle mass) was also associated with frailty and worse short-term clinical outcomes. CONCLUSION: The SI, a simple calculation from kidney function markers, is a significant predictor of muscle mass in this validation cohort of ICU patients. A low SI was associated with longer hospital length of stay and frailty. Future studies could explore whether the use of SI assists with identifying patients likely to benefit from pharmacotherapy-, nutrition-, or physical therapy-based interventions.

A Case of Severe, Prolonged, Refractory Hypophosphatemia After Zoledronic Acid Administration.

Zoledronic acid (ZA) administration has been associated with electrolyte abnormalities, including hypocalcemia, hypomagnesemia, hypokalemia, and hypophosphatemia. We describe a case of severe, refractory hypophosphatemia in a patient who received ZA for hypercalcemia of malignancy (HCM). Little data are available that describe the incidence or degree of severity of hypophosphatemia that can occur following ZA administration. In addition, no formal recommendations exist to guide monitoring for or management of electrolyte derangements in the setting of bisphosphonate use. Our patient required daily, high-dose phosphorus replacement beginning day 4 following ZA administration. The average daily dose of phosphorus, including both intravenous and enteral administration, was highest in the first 2 weeks after ZA, averaging 77 mmol/d days 4 through 15, and does not include sources of phosphorus from the patient's nutrition support. Despite this high amount of supplementation, which was well beyond what meets normal daily requirements and the amount expected to treat "usual" hypophosphatemia, the patient did not achieve sustained normal serum phosphorus levels for over 30 days after ZA. ZA is a favorable option for treating HCM because of its longer duration of action, potent serum calcium-lowering effects, and favorable safety profile. The risk of hypophosphatemia with ZA use is reviewed.