Hypocaloric, high-protein nutrition therapy for critically ill patients with obesity

We published the first article that addressed hypocaloric, high-protein enteral nutrition therapy for critically ill patients with obesity more than 10 years ago. This study demonstrated that it was possible to successfully achieve this mode of therapy with a commercially available high-protein enteral formula and concurrent use of protein supplements. This study was also the first to demonstrate improved clinical outcomes with the use of hypocaloric, high-protein nutrition therapy. The results of this study, its unique findings, and shortcomings are discussed. Subsequent studies have added clarity to the effective use of this therapy, including its use in home parenteral nutrition patients, patients with class III obesity, and older patients with obesity.

Inadvertent exaggerated anticoagulation following use of bismuth subsalicylate in an enterally fed patient receiving warfarin therapy

We report a case of an inadvertent increase in the international normalized ratio (INR) after the addition of bismuth subsalicylate for the treatment of diarrhea in an enterally fed patient receiving warfarin therapy. A 56-year-old Caucasian female presented to the trauma intensive care unit (ICU) with multiple lower extremity fractures. Warfarin was initiated for deep vein thrombosis prophylaxis due to the patient's inability to ambulate. The target INR was 2-3. Continuous intragastric enteral feeding was withheld 1 hour before and 1 hour after intragastric administration of warfarin. Bismuth subsalicylate 30 mL every 4 hours was prescribed for diarrhea. Within 3 days after starting bismuth subsalicylate therapy, the patient's INR increased from 2.56 to 3.54 and minor bleeding was noted from the patient's tracheostomy site. No significant change in warfarin dosage, variability in vitamin K intake, or medications that potentially alter warfarin metabolism were present during the unexpected rise in INR. When the bismuth subsalicylate was discontinued, the patient's INR stabilized into the target range on the same warfarin dose given at the time of the supratherapeutic INR. Salicylate displaces warfarin from plasma protein binding sites and may result in a significant increase in INR secondary to redistribution of warfarin to the free active form. Evaluation of this case report using the Drug Interaction Probability Scale and Naranjo Adverse Drug Reaction Probability Scale yielded scores consistent with a probable adverse drug interaction. Bismuth subsalicylate exaggerates warfarin's anticoagulant response and its concurrent use during warfarin therapy should be avoided.

Improved safety with intravenous insulin therapy for critically ill patients with renal failure

OBJECTIVE

The aim of this study was to evaluate the safety and efficacy of a new intravenous (IV) regular human insulin infusion (RHI) algorithm for glycemic control in critically ill patients with renal failure.

METHODS

Adult trauma patients with renal failure who received a new RHI algorithm were compared with those who received the discontinued RHI algorithm (historical control). Target blood glucose (BG) concentration was 70 to 149 mg/dL (3.9-8.3 mmol/L). Patients were evaluated for 7 d while receiving the RHI infusion and continuous enteral or parenteral nutrition.

RESULTS

Mean BG was higher for the new RHI algorithm group (n = 25) compared with control (n = 21): 145 ± 10 mg/dL or 8.1 ± 0.6 mmol/L versus 133 ± 14 mg/dL or 7.4 ± 0.8 mmol/L (P = 0.001). The new RHI algorithm resulted in less time within the target BG range (11.9 ± 2.5 h/d versus 16.1 ± 3.3 h/d; P = 0.001); however, BGs were within 70 to 179 mg/dL (or 3.9-10 mmol/L) for 16.3 ± 2.6 h/d. The proportion of patients who experienced an episode of moderate hypoglycemia (BG 40-60 mg/dL or 2.2-3.3 mmol/L) or severe hypoglycemia (BG < 40 mg/dL or 2.2 mmol/L) was decreased (32% versus 76%; P = 0.001) and eliminated (0% versus 29%, P = 0.006), respectively.

CONCLUSIONS

The new RHI algorithm improved patient safety by decreasing the prevalence of moderate hypoglycemia and eliminating severe hypoglycemia. The duration of glycemic control within the target BG range was decreased, but acceptable within a higher target BG ceiling.

Influence of aging on nitrogen accretion during critical illness

BACKGROUND

Aging adversely affects nitrogen accretion during health, but its effect during critical illness is unknown. Nitrogen balance (NB) response to varying protein intakes was compared between critically ill, older and younger patients.

METHODS

Adult patients admitted to the trauma intensive care unit, given enteral or parenteral nutrition, and who had a NB determination within 5-14 days after injury were evaluated. Patients with renal or hepatic disease were excluded. Patients were categorized as older (≥60 years) or younger (18-59 years of age). Data are given as mean ± SD or median [interquartile range].

RESULTS

Fifty-four older (69 [65, 77] years) and 195 younger (35 [27, 47] years) patients were evaluated. NB was blunted for the older patients with an observed trending improvement in NB from -13.5 ± 5.5 to -5.6 ± 8.8 g/d (P = NS) noted at 1.5-1.99 g/kg/d. NB improved from -22.2 ± 8.2 to -11.8 ± 9.9 g/d (P = .05) at 1-1.49 g/kg/d and modestly thereafter for each 0.5-g/kg/d increase in protein intake for the younger patients. Serum urea nitrogen concentration during the NB was highly variable but overall greater for the older patients (20 [14, 33] vs 15 [10, 20] mg/dL, P = .001).

CONCLUSIONS

Improvement in nitrogen accretion was blunted at lower protein intakes in critically ill, older patients compared with younger patients. Individualization of protein intake is warranted.

The obesity paradox in the ICU: real or not?

The obesity paradox has been used to describe the observed phenomenon described by several studies that indicated improved survival for critically ill patients with mild to moderate obesity when compared with their lean counterparts. The study by Arabi and coworkers challenges the obesity paradox concept for critically ill obese patients with septic shock. Their data indicate that obesity, per se, does not significantly improve mortality when outcomes are adjusted for differences in baseline characteristics and sepsis interventions. Further studies are needed to assess the influence of body weight, lean weight, and fat mass for optimizing fluid resuscitation, pharmacotherapy, and nutritional therapy for critically ill patients with sepsis.

Safety and efficacy of intravenous hypotonic 0.225% sodium chloride infusion for the treatment of hypernatremia in critically ill patients

BACKGROUND

The purpose of this study was to evaluate the safety and efficacy of central venous administration of a hypotonic 0.225% sodium chloride (one-quarter normal saline [¼ NS]) infusion for critically ill patients with hypernatremia.

METHODS

Critically ill, adult patients with traumatic injuries and hypernatremia (serum sodium [Na] >150 mEq/L) who were given ¼ NS were retrospectively studied. Serum sodium, fluid balance, free water intake, sodium intake, and plasma free hemoglobin concentration (fHgb) were assessed.

RESULTS

Twenty patients (age, 50 ± 18 years; Injury Severity Score, 29 ± 12) were evaluated. The ¼ NS infusion was given at 1.5 ± 1.0 L/d for 4.6 ± 1.6 days. Serum sodium concentration decreased from 156 ± 4 to 143 ± 6 mEq/L (P < .001) over 3-7 days. Total sodium intake was decreased from 210 ± 153 to 156 ± 112 mEq/d (P < .05). Daily net fluid balance was not significantly increased. Plasma fHgb increased from 4.9 ± 5.4 mg/dL preinfusion to 8.9 ± 7.4 mg/dL after 2.6 ± 1.3 days of continuous intravenous (IV) ¼ NS in 10 patients (P = .055). An additional 10 patients had a plasma fHgb of 10.2 ± 9.0 mg/dL during the infusion. Hematocrit and hemoglobin decreased (26% ± 3% to 24% ± 2%, P < .001 and 9.1 ± 1.1 to 8.2 ± 0.8 g/dL, P < .001, respectively).

CONCLUSIONS

Although IV ¼ NS was effective for decreasing serum sodium concentration, evidence for minor hemolysis warrants further research to establish its safety before its routine use can be recommended.

Review of Intravenous Selenium Infusions for the Critically III Patient

Attempts to improve mortality for patients with sepsis, severe sepsis, systemic inflammatory response syndrome, and septic shock continue to challenge health care professionals. This review will explore how the antioxidant, and possibly pro-oxidant, properties of selenium may benefit critically ill patients. Literature examining improvements in clinical outcomes from intravenous (IV) selenium infusion therapy will be discussed. Although there is not an overwhelming amount of knowledge about IV selenium and its effect on morbidity and mortality, this review will outline recent research evaluating the use of IV selenium infusions and its potential to decrease morbidity and mortality for different critically ill patient populations.

Transitional NPH insulin therapy for critically ill patients receiving continuous enteral nutrition and intravenous regular human insulin

BACKGROUND

The intent of this study was to evaluate the efficacy and safety of transitioning from a continuous intravenous (IV) regular human insulin (RHI) or intermittent IV RHI therapy to subcutaneous neutral protamine Hagedorn (NPH) insulin with intermittent corrective IV RHI for critically ill patients receiving continuous enteral nutrition (EN).

METHODS

Data were obtained from critically ill trauma patients receiving continuous EN during transitional NPH insulin therapy. Target blood glucose concentration (BG) range was 70-149 mg/dL. BG was determined every 1-4 hours.

RESULTS

Thirty-two patients were transitioned from a continuous IV RHI infusion (CIT) to NPH with intermittent corrective IV RHI therapy. Thirty-four patients had NPH added to their preexisting supplemental intermittent IV RHI therapy (SIT). BG concentrations were maintained in the target range for 18 ± 3 and 15 ± 4 h/d for the CIT and SIT groups, respectively (P < .05). Thirty-eight percent of patients experienced a BG <60 mg/dL, and 9% had a BG <40 mg/dL. Hypoglycemia was more prevalent for those who were older (P < .01) or exhibited greater daily BG variability (P < .01) or worse HgbA1C (p < 0.05).

CONCLUSION

Transitional NPH therapy with intermittent corrective IV RHI was effective for achieving BG concentrations within 70-149 mg/dL for the majority of the day. NPH therapy should be implemented with caution for those who are older, have erratic daily BG control, or have poor preadmission glycemic control.

Evaluation of nursing adherence to a paper-based graduated continuous intravenous regular human insulin infusion algorithm

OBJECTIVE

The use of continuous intravenous regular human insulin (RHI) infusion is often necessary to achieve glycemic control in critically ill patients. Because insulin is a high-risk medication owing to the potential for severe hypoglycemia, it is imperative that insulin infusion algorithms are designed to be safe, effective, and instructionally clear. The safety and efficacy of our intravenous RHI infusion algorithm protocol has been previously established (Nutrition 2008;24:536-45); however, the protocol violations by nursing personnel were not examined. The objective of this study was to assess nursing adherence to our RHI infusion algorithm.

METHODS

Continuous RHI infusion algorithm violations were retrospectively evaluated in adult patients admitted to a trauma intensive care unit who received concurrent continuous enteral and/or parenteral nutrition therapy and our algorithm for at least 3 d. Blood glucose (BG) monitoring was done every 1 to 2 h with the target BG at 70 to 149 mg/dL (3.9 to 8.3 mmol/L). Nursing adherence to the RHI infusion protocol was evaluated for each patient by comparing the adjustments in insulin infusion rates documented by the nursing personnel with the prescribed adjustments per our graduated continuous intravenous RHI infusion algorithm.

RESULTS

A total of 4150 BG measurements necessitating the determination of the appropriate RHI dosage rate by nursing personnel in 40 patients occurred during the observational period. The target BG was achieved for a mean of 20 h/d and none of the patients had an episode of severe hypoglycemia (BG <40 mg/dL or 2.2 mmol/L). The overall rate of algorithm violations was 12.1%. The algorithm violations accounted for a single episode of mild to moderate hypoglycemia (BG 40 to 60 mg/dL or 2.2 to 3.3 mmol/L) in 4 patients and 65 total episodes of hyperglycemia (BG ≥150 mg/dL or 8.3 mmol/L) in 18 patients.

CONCLUSION

An adherence rate of nearly 90% is indicative of excellent nursing adherence compared with other published paper-based algorithms that examined protocol adherence. These data, combined with our previously published glycemic control data, indicate that this RHI infusion algorithm is an effective one for hyperglycemic trauma patients receiving continuous enteral and/or parenteral nutritional therapy.

Optimal caloric intake for critically ill patients: first, do no harm

Despite considerable efforts to define energy requirements for critically ill patients, no single method has been found to be precise and unbiased for all patients. As a result, clinicians have used various methods that may overestimate energy requirements for some patients. Provision of target caloric intake without regard to the complications of overfeeding, such as hyperglycemia, hypercapnia, or gastric feeding intolerance, could result in overall detrimental clinical outcome. Inadequate nutrition support is also associated with adverse clinical outcomes that necessitate optimization of delivery and tolerance of the nutrition regimen. A pivotal paper by Krishnan and colleagues published in 2003 brought these issues to the forefront of clinical practice. Key papers that support or refute the practice of "permissive underfeeding" are reviewed. Further research is necessary to determine the minimum amount of nutrition required to achieve a therapeutic benefit as well as to ascertain at what amount of additional nutrition intake offers no further improvement in clinical outcome.

Use of a standardized progress note and assessment form for performance evaluation and quality improvement

In addition to filling patient care-related duties, the Nutrition Support Service also serves as a platform for experiential education and training of pharmacy residents, surgical interns, doctor of pharmacy students, and graduate dietetic students. Because of the diversity in experience and training among members of the team and their trainees, a standardized progress note form with a subsequent progress note assessment form was developed to maintain consistency and to ensure a certain level of quality in the daily progress notes written by the trainees. The instructor randomly chose one of the trainee's patient progress notes for verbal and written evaluation weekly. Twelve trainees from July 2009 to January 2010 were evaluated. A significant improvement in weekly performance scores (from an average score of 74% ± 12% to 91% ± 7% to 96% ± 6%) was noted by the second and third weeks compared with the first week, respectively (P < .001). Trainees were unanimous that this tool facilitated improvement of their clinical skills and ability to write effective daily progress notes.

Increased hypoglycemia associated with renal failure during continuous intravenous insulin infusion and specialized nutritional support

OBJECTIVE

To evaluate glycemic control for critically ill, hyperglycemic trauma patients with renal failure who received concurrent intensive insulin therapy and continuous enteral nutrition (EN) or parenteral nutrition (PN).

METHODS

Adult trauma patients with renal failure who were given EN or PN concurrently with continuous graduated intravenous regular human insulin (RHI) infusion for at least 3 d were evaluated. Our conventional RHI algorithm was modified for those with renal failure by allowing greater changes in blood glucose (BG) concentrations before the infusion rate was escalated. BG concentration was determined every 1 to 2 h while receiving the insulin infusion. BG control was evaluated on the day before RHI infusion and for a maximum of 7 d while receiving RHI. Target BG during the RHI infusion was 70 to 149 mg/dL (3.9 to 8.3 mmol/L). Glycemic control and incidence of hypoglycemia for those with renal failure were compared with a historical cohort of critically ill, hyperglycemic trauma patients without renal failure given our conventional RHI algorithm.

RESULTS

Twenty-one patients with renal failure who received the modified RHI algorithm were evaluated and compared with 40 patients without renal failure given our conventional RHI algorithm. Average BG concentration was significantly greater for those with renal failure (133±14 mg/dL or 7.3±0.7 mmol/L) compared with those without renal failure (122±15 mg/dL or 6.8±0.8 mmol/L), respectively (P<0.01). Patients with renal failure showed worsened glycemic variability, with 16.1±3.3 h/d within the target BG range, 6.9±3.2 h/d above the target BG range, and 1.4±1.1 h/d below the target BG range compared with 19.6±4.7 h/d (P<0.001), 3.4±3.0 h/d (P<0.001), and 0.7±0.8 h/d (P<0.01) for those without renal failure, respectively. Moderate hypoglycemia (<60 mg/dL or<3.3 mmol/L) occurred in 76% of patients with renal failure compared with 35% without renal failure (P<0.005). Severe hypoglycemia (BG<40 mg/dL or<2.2 mmol/L) occurred in 29% of patients with renal failure compared with none of those without renal failure (P<0.001).

CONCLUSION

Despite receiving a modified RHI infusion, critically ill trauma patients with renal failure are at greater risk for developing hypoglycemia and have more glycemic variability than patients without renal failure.

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.

Influence of traumatic brain injury on potassium and phosphorus homeostasis in critically ill multiple trauma patients

OBJECTIVE

The intent of this study was to ascertain whether multiple trauma patients with traumatic brain injury (TBI) had lower serum concentrations of potassium and phosphorus and required more aggressive supplementation than multiple trauma patients without TBI.

METHODS

Ventilator-dependent adult patients without renal impairment who were admitted to the trauma intensive care unit or neurosurgical intensive care unit and who received enteral nutrition were evaluated for the first 14 d after hospital admission. Patients were grouped according to the presence or absence of TBI. Target serum concentrations for potassium and phosphorus were 4 mEq/L and 4 mg/dL, respectively. Electrolyte repletion therapy was given according to the nutritional support service guidelines.

RESULTS

Fifty trauma patients (25 with and without TBI) were studied. Daily serum potassium concentrations were consistently lower for those with TBI (P < or = 0.001), whereas the mean net potassium intake was greater (1.3 +/- 0.5 versus 0.7 +/- 0.3 mEq x kg(-1) x d(-1), respectively, P < or = 0.001). Serial serum phosphorus concentrations were similar between groups (P = NS) except for a significantly lower serum phosphorus concentration for trauma patients with TBI on day 3 after hospital admission (2.5 +/- 0.5 versus 2.9 +/- 0.7 mg/dL, respectively, P < or = 0.05). However, the mean net phosphorus intake was significantly greater for trauma patients with TBI (0.65 +/- 0.25 versus 0.45 +/- 0.17 mmol x kg(-1) x d(-1), P < or = 0.001).

CONCLUSION

Potassium and phosphorus requirements are greater for multiple trauma patients with TBI compared with those without TBI.

Glycemic Control during Critical Illness: Tight or Not?

Nutrition Support Pharmacist features issues pertinent to the practice of clinical pharmacy in the area of metabolic support. In this review, a critical analysis of six current major intensive insulin therapy trials (Leuven I, Leuven II, Leuven III, NICE-SUGAR, VISEP, and Glucontrol) for critically ill surgical and medical patients is provided. Practical suggestions for managing hyperglycemia, defining an effective target blood glucose concentration range, avoiding hypoglycemia, and designing a safe and effective insulin infusion algorithm are given.

Supporting Literature for an Evidence-Based Metabolic Support Practice

Nutrition Support Pharmacist features issues pertinent to the practice of clinical pharmacy in the area of metabolic support. This column is edited by Dr. Roland N. Dickerson, Professor of Clinical Pharmacy, University of Tennessee Health Science Center, and Clinical Pharmacist, Nutrition Support at the Regional Medical Center at Memphis.