Disparate response to metoclopramide therapy for gastric feeding intolerance in trauma patients with and without traumatic brain injury.

Patients with traumatic brain injury (TBI) have delayed gastric emptying and often require prokinetic drug therapy to improve enteral feeding tolerance. The authors hypothesized that metoclopramide was less efficacious for improving gastric feeding tolerance for trauma patients with TBI compared to trauma patients without TBI. A retrospective analysis was conducted of patients admitted to the trauma or neurosurgical intensive care unit who received gastric feeding from January 2006 to April 2008. Gastric feeding intolerance was defined by a gastric residual volume >200 mL or emesis with abdominal distension or discomfort. Patients with gastric feeding intolerance were given metoclopramide 10 mg intravenously every 6 hours, followed by a dose escalation to 20 mg, and then combination therapy with metoclopramide and erythromycin 250 mg intravenously every 6 hours if intolerance persisted. In total, 882 trauma patients (49% with TBI) were evaluated. TBI patients had a higher incidence of gastric feeding intolerance than those without TBI (18.6% vs 10.4%, P < or = .001). Efficacy rates for metoclopramide 10 mg, metoclopramide 20 mg, and metoclopramide-erythromycin were 55%, 62%, and 79%, respectively (P < or = .03). Metoclopramide failure occurred in 54% of patients with TBI compared to 35% of patients without TBI, respectively (P < or = .02), due to a greater prevalence of tachyphylaxis. Single-drug therapy with metoclopramide was less effective for TBI trauma patients compared to trauma patients without TBI. Combination therapy with erythromycin as first-line therapy for TBI trauma patients with gastric feeding intolerance is indicated if there are no contraindications or significant drug interactions.

Potential aluminum exposure from parenteral nutrition in patients with acute kidney injury.

BACKGROUND: Patients' exposure to and potential toxicity from aluminum in parenteral nutrition (PN) formulations is an important concern of healthcare providers. OBJECTIVE: To determine the potential for aluminum toxicity caused by PN in hospitalized adults who have risk factors of both acute kidney injury and PN. METHODS: Adults who required PN and had a serum creatinine (SCr) level at least 1.5 times greater than the admission SCr on the first day of PN were studied in a retrospective fashion. Protein was administered based on whether hemodialysis was being used (0.6-1 g/kg/day without hemodialysis; 1.2-1.5 g/kg/day with hemodialysis). Aluminum exposure was determined for each patient by multiplying the volume of each PN component by its concentration of aluminum. Unpaired t-tests, Fisher's exact test, and analysis of variance were used for statistical analysis. Data are presented as mean +/- SD. RESULTS: Thirty-six patients (aged 50.4 +/- 20.4 y; weight 90.2 +/- 32.8 kg) were studied. Initial serum urea nitrogen and SCr were 47 +/- 23 and 3.3 +/- 1.4 mg/dL, respectively. Twelve patients received hemodialysis. The mean aluminum exposure was 3.8 +/- 2 microg/kg/day in the 36 patients. Of these, 29 had safe calculated aluminum exposure (<5 microg/kg/day) and 7 had high calculated aluminum exposure (>5 microg/kg/day). Patients with safe aluminum exposure had significantly higher SCr levels than did those with high aluminum exposure (3.5 +/- 1.5 vs 2.2 +/- 0.7 mg/dL; p < 0.04). Patients with high aluminum exposure received significantly more aluminum from calcium gluconate compared with those who had safe aluminum exposure (357 +/- 182 vs 250 +/- 56 microg/day; p < 0.02). Limitations of the study include its retrospective design, which resulted in calculated versus direct measurement of aluminum. CONCLUSIONS: Using our calculations, we believe that most patients with acute kidney injury who require PN do not receive excessive exposure to aluminum from the PN formulation, despite having 2 risk factors (acute kidney injury, PN) for aluminum toxicity.

Safety and efficacy of a graduated intravenous insulin infusion protocol in critically ill trauma patients receiving specialized nutritional support.

OBJECTIVE: The intent of this study was to evaluate the safety and efficacy of our protocol for providing continuous intravenous regular human insulin (RHI) infusion to hyperglycemic critically ill trauma patients receiving specialized nutritional support. METHODS: Capillary blood glucose (BG) concentrations were determined every 1-2 h. Glucose control was defined as a BG concentration in the target range of 70-149 mg/dL (3.9-8.3 mmol/L). Data were recorded for 1 d before the RHI infusion and for a maximum of 8 d thereafter while receiving the RHI infusion. RESULTS: Forty adult critically ill trauma patients received 102 +/- 62 units of RHI daily for 10 +/- 6 d. BG control was achieved within 5 +/- 3 h. BG decreased from 194 +/- 55 mg/dL (10.8 +/- 3.1 mmol/L) to 134 +/- 19 mg/dL (7.4 +/- 1.1 mmol/L) after 1 d of RHI infusion (P < 0.001). Average daily BG ranged from 119 to 124 mg/dL and the target range was maintained for 19.6 +/- 4.7 h/d. None of the patients experienced severe hypoglycemia (<40 mg/dL); 14 patients had asymptomatic hypoglycemia (<60 mg/dL or <3.3 mmol/L) for a total of 23 episodes out of 4140 measurements (0.56%). Estimated creatinine clearance for those with hypoglycemia was 69 +/- 32 mL/min compared with 117 +/- 58 mL/min for the others (P < 0.01). CONCLUSION: Our protocol was safe and effective for the management of hyperglycemia in critically ill trauma patients receiving specialized nutritional support but should be used with caution in patients with renal insufficiency.

Treatment of moderate to severe acute hypocalcemia in critically ill trauma patients.

BACKGROUND: Our recent data indicate that 21% of critically ill, adult, multiple-trauma patients receiving specialized nutrition support experience hypocalcemia. However, evidence-based methods for the treatment of moderate to severe acute hypocalcemia (ionized calcium concentration [iCa] <1 mmol/L) are lacking. METHODS: The efficacy of an infusion of 4 g of calcium gluconate was evaluated in 20 critically ill, adult, multiple-trauma patients with moderate to severe hypocalcemia (iCa <1 mmol/L). The calcium gluconate was infused at a rate of 1 g/h in a small volume admixture. A serum iCa determination was obtained on the following day. RESULTS: Calcium gluconate infusion significantly increased serum iCa from 0.90 +/- 0.08 mmol/L to 1.16 +/- 0.11 mmol/L (p < .001) on the following day. This dosage regimen was successful for achieving a serum iCa >1 mmol/L for 19 of 20 (95%) hypocalcemic patients and achieved a concentration >1.12 mmol/L in 14 (70%) of the patients. Two patients developed mild hypercalcemia (iCa of 1.34 mmol/L and 1.38 mmol/L) postinfusion. CONCLUSIONS: A short-term infusion of 4 g of intravenous (IV) calcium gluconate for the treatment of moderate to severe hypocalcemia appears to be a promising regimen for critically ill, adult, multiple-trauma patients.

Dose-dependent characteristics of intravenous calcium therapy for hypocalcemic critically ill trauma patients receiving specialized nutritional support.

OBJECTIVE: The purpose of this investigation was to evaluate the dose-dependent characteristics of intravenous calcium gluconate therapy for hypocalcemic critically ill patients. METHODS: The dose-dependent characteristics of 2 g versus 4 g of intravenous calcium gluconate therapy were evaluated in 25 critically ill, adult multiple trauma patients with hypocalcemia. The calcium gluconate was infused at a rate of 1 g/h for both groups. Patients weighed within 90% to 120% of ideal body weight, had normal renal function, did not receive diuretic therapy, and did not have anasarca. RESULTS: Fifteen patients with mild hypocalcemia (serum ionized calcium concentration [iCa] 1-1.12 mmol/L) were given 2 g of calcium gluconate. Ten patients with moderate to severe hypocalcemia (iCa <1 mmol/L) were given 4 g. Each dosage group had a significant (P < or = 0.001) increase in iCa (from 1.07 +/- 0.05 to 1.17 +/- 0.05 mmol/L and from 0.92 +/- 0.08 to 1.16 +/- 0.11 mmol/L, respectively). Each dosage group retained about half of the dose in the exchangeable calcium space (P = NS between groups), but the higher dosage group retained significantly more elemental calcium overall (81 +/- 38 versus 201 +/- 50 mg, respectively, P < or = 001). Serum ionized calcium concentrations achieved a plateau without a further decline in iCa by 10 h after completion of the infusion for each dosage. CONCLUSION: About half of the administered elemental calcium dose was retained for each dosage group, with the higher dose (4 g) resulting in significantly more elemental calcium retention in the exchangeable calcium space. An iCa determination performed about > or =10 h after the completion of the calcium gluconate infusion should be sufficient time to ensure equilibration of iCa to assess the efficacy of the therapy. This mode of calcium therapy serves as an effective means for providing calcium to the acutely hypocalcemic, critically ill, multiple trauma patient.

A new graduated dosing regimen for phosphorus replacement in patients receiving nutrition support.

BACKGROUND: Hypophosphatemia is a common metabolic complication in patients receiving specialized nutrition support. We changed our previously reported dosing algorithm because the low dose no longer appeared to be effective at increasing serum phosphorus concentrations. The purpose of this study was to evaluate the safety and efficacy of a revised weight-based phosphorus-dosing algorithm in critically ill trauma patients receiving specialized nutrition support. METHODS: Seventy-nine adult trauma patients with hypophosphatemia (serum phosphorus concentration < or = 0.96 mmol/L) receiving nutrition support received an IV dose of phosphorus on day 1 according to the serum concentration of phosphorus: 0.73-0.96 mmol/L (0.32 mmol/kg, low dose), 0.51-0.72 mmol/L (0.64 mmol/kg, moderate dose), and < or = 0.5 mmol/L (1 mmol/kg, high dose). The IV phosphorus bolus dose was administered at 7.5 mmol/hour. Generally, patients with a serum potassium concentration <4 mmol/L received potassium phosphate and patients with a serum potassium concentration > or = 4 mmol/L received sodium phosphate. Patients who still had hypophosphatemia on day 2 were dosed using the new dosing algorithm by the nutrition support service according to that day's serum concentration of phosphorus, or empirically by the trauma service. RESULTS: Of the 79 patients studied, 57 were male and 22 were female with a mean age of 44.8 +/- 20.6 years. Mean Injury Severity Scores and APACHE-II scores were 27.1 +/- 11.6 and 15.2 +/- 6.8, respectively. There was no difference in baseline characteristics among the 3 dosing groups. Of the 79 patients, 34 received the low dose, 30 received the moderate dose, and 15 received the high dose of phosphorous. Mean serum phosphorous concentrations on day 2 were significantly increased in the moderate-dosed group (0.64 +/- 0.06 to 0.77 +/- 0.22 mmol/L, p < .05) and high-dosed group (0.38 +/- 0.06 to 0.93 +/- 0.32 mmol/L, p < .01), respectively, when compared with day 1. Mean serum phosphorus concentrations were normal in all 3 groups on day 3. Serum concentrations of magnesium, sodium, and potassium, as well as arterial pH, were stable across the study. Mean concentrations of ionized calcium were not significantly different in any of the 3 dosing groups across the study period. CONCLUSIONS: This weight-based phosphorus-dosing algorithm is safe for use in critically ill patients receiving nutrition support. The moderate and severe-dose regimens effectively increase serum phosphorus concentrations.

Factors causing interrupted delivery of enteral nutrition in trauma intensive care unit patients.

BACKGROUND: The intent of this study was to ascertain the adequacy of delivery of enteral nutrition (EN) to critically ill adult multiple trauma patients and to identify potential detrimental factors that affect EN delivery. METHODS: Retrospective observational study. Trauma intensive care unit (TICU) in a university-affiliated hospital. Adult patients (>/=18 years of age) admitted to the TICU who received enteral feeding. RESULTS: Fifty-six adult patients were enrolled for study. Patients received, on average, 67% +/- 19% of what was prescribed for 5.7 +/- 2.0 days. A total of 222 occurrences for temporary discontinuation of tube feeding were identified. Gastrointestinal intolerance, as defined by a gastric residual volume of >150 mL, abdominal pain, or >3 liquid stools per day, accounted for only 11% of the occurrences for discontinuation of feeding. Surgery (27%) and diagnostic procedures (15%) represented the majority of reasons for inadequate nutrient delivery. Minor factors for EN interruptions were mechanical feeding tube problems (8%), pharmacy delivery delay (4%), and miscellaneous factors (3%). Multiple and unknown reasons contributed to 14% and 18% of the occurrences, respectively. CONCLUSIONS: Surgery and diagnostic procedures accounted for the largest factor in enteral feeding discontinuations in our critically ill trauma patients. Gastrointestinal intolerance contributed a minor role in the temporary discontinuation of enteral feeding.