Salmaan Kanji

Enteric absorption and pharmacokinetics of oseltamivir in critically ill patients with pandemic (H1N1) influenza

Background: Whether the enteric absorption of the neuraminidase inhibitor oseltamivir is impaired in critically ill patients is unknown. We documented the pharmacokinetic profile of oseltamivir in patients admitted to intensive care units (ICUs) with suspected or confirmed pandemic (H1N1) influenza. Methods: We included 41 patients 18 years of age and older with suspected or confirmed pandemic (H1N1) influenza who were admitted for ventilatory support to nine ICUs in three cities in Canada and Spain. Using tandem mass spectrometry, we assessed plasma levels of oseltamivir free base and its active metabolite carboxylate at baseline (before gastric administration of the drug) and at 2, 4, 6, 9 and 12 hours after the fourth or later dose. Results: Among the 36 patients who did not require dialysis, the median concentration of oseltamivir free base was 10.4 (interquartile range [IQR] 4.8–14.9) μg/L; the median concentration of the carboxylate metabolite was 404 (IQR 257–900) μg/L. The volume of distribution of the carboxylate metabolite did not increase with increasing body weight (R2 = 0.00, p = 0.87). The rate of elimination of oseltamivir carboxylate was modestly correlated with estimations of creatinine clearance (R2 = 0.27, p < 0.001). Drug clearance in the five patients who required continuous renal replacement therapy was about one-sixth that in the 36 patients with relatively normal renal function. Interpretation: Oseltamivir was well absorbed enterically in critically ill patients admitted to the ICU with suspected or confirmed pandemic (H1N1) influenza. The dosage of 75 mg twice daily achieved plasma levels that were comparable to those in ambulatory patients and were far in excess of concentrations required to maximally inhibit neuraminidase activity of the virus. Adjustment of the dosage in patients with renal dysfunction requiring continuous renal replacement therapy is appropriate; adjustment for obesity does not appear to be necessary.

Effect of low-calorie parenteral nutrition on the incidence and severity of hyperglycemia in surgical patients: a randomized, controlled trial.

Objective:To determine the effect of a low-calorie parenteral nutrition (PN) regimen on the incidence and severity of hyperglycemia and insulin requirements. Design:Prospective, randomized, clinical trial. Setting:Urban, university-affiliated, level-I trauma center. Patients:Consecutive surgical patients requiring PN. Interventions:Patients were randomized to receive either a low-calorie PN formulation (20 nonprotein kilocalories per kg per day) or a standard PN formulation (30 nonprotein kilocalories per kg per day). Lipid-derived calories were standardized to 1000 kilocalories three times weekly for all patients; consequently, the number of calories varied only by the amount of carbohydrate administered. Protein requirements were individualized on the basis of estimated metabolic stress. Hyperglycemia was defined as a blood glucose level ≥200 mg/dL. Measurements and Main Results:Forty patients were evaluated (low-calorie PN, n = 20; standard PN, n = 20). Demographics of the two groups were similar. The incidence of hyperglycemic events was significantly lower in the low-calorie group (0% [0–0.5] vs. 33.1% [0–58.4]; p = .001]. Additionally, the severity of hyperglycemia was also lower in the low-calorie group (mean glucose area under the curve = 118 ± 22 [mg·hr]/dL vs. 172 ± 44 [mg·hr]/dL; p < .001). This resulted in lower average daily insulin requirements (0 [0–0] units vs. 10.9 [0–25.6] units; p < .001.). The only predictor of hyperglycemia was a dextrose administration rate >4 mg/kg/min. Conclusions:Administration of a low-calorie PN formulation resulted in fewer and less-severe hyperglycemic events and lower insulin requirements. PN regimens should not exceed a dextrose administration rate of 4 mg/kg/min to avoid hyperglycemic events.

Sedation Assessment in Critically Ill Adults

OBJECTIVE: To review methods for assessing sedation in critically ill adults, discuss their impact on patient outcomes, and provide recommendations for implementing these methods into clinical practice in the intensive care unit (ICU). DATA SOURCES: A computerized search of MEDLINE from 1980 through June 2000 and a manual search of abstracts presented at recent critical care meetings were performed. STUDY SELECTION AND DATA EXTRACTION: Sedation assessment tools that have been used to titrate therapy in adult, critically ill patients were identified. Special emphasis was placed on sedation assessment instruments that have been prospectively validated. Objective methods that have been used to assess sedation therapy were also identified. DATA SYNTHESIS: Twenty-three adult sedation assessment instruments were identified. Few scales have been prospectively evaluated for validity (n = 6) or reliability (n = 7). Other methods of sedation assessment were identified (e.g., bispectral index monitor); however, most of these methods have only been studied in small subsets of critically ill patients. CONCLUSIONS: Incorporation of sedation assessment into ICU clinical practice may improve patient care. These sedation assessment instruments must be further evaluated to determine their impact on quality of care and ICU length of stay.

Efficacy and safety of dopamine agonists in traumatic brain injury: a systematic review of randomized controlled trials.

In the intensive care unit, dopamine agonists (DA) have been used in traumatic brain injury (TBI) patients to augment or accelerate cognitive recovery and rehabilitation. However, the efficacy and safety of DA in this population is not well established. We conducted a systematic review of randomized controlled trials (RCTs) examining the clinical efficacy and safety of DA in patients with TBI. We searched MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials, comparing DA to either placebo, standard treatment, or another active comparator. There was no restriction for age, date, or language of publication. Sensitivity analyses were planned to evaluate the potential effect of timing of TBI, age, drugs, and year of publication on efficacy. Among the 790 citations identified, 20 RCTs evaluating methylphenidate, amantadine, and bromocriptine were eligible. Significant clinical heterogeneity was observed between and within studies, which precluded any pooling of data. Efficacy outcomes included mainly neuropsychological measures of cognitive functioning. A total of 76 different neuropsychological tests were used, but most of them (59%) only once. Only 5 studies systematically assessed safety. No trend could be drawn from the analysis of efficacy and safety. Important sources of bias in the studies were of major concern. Considering the absence of consensus regarding clinical outcome, the lack of safety assessment, and the high risk of bias in the included trials, more research is warranted before DA can be recommended in critically ill TBI patients.

Determination of neurologic prognosis and clinical decision making in adult patients with severe traumatic brain injury: a survey of Canadian intensivists, neurosurgeons, and neurologists.

Objectives:Accurate prognostic information in patients with severe traumatic brain injury remains limited, but mortality following the withdrawal of life-sustaining therapies is high and variable across centers. We designed a survey to understand attitudes of physicians caring for patients with severe traumatic brain injury toward the determination of prognosis and clinical decision making on the level of care. Design, Setting, and Participants:We conducted a cross-sectional study of intensivists, neurosurgeons, and neurologists that participate in the care of patients with severe traumatic brain injury at all Canadian level 1 and level 2 trauma centers. Intervention:None. Measurements:The main outcome measure was physicians’ perceptions of prognosis and recommendations on the level of care. Main Results:Our response rate was 64% (455/712). Most respondents (65%) reported that an accurate prediction of prognosis would be most helpful during the first 7 days. Most respondents (>80%) identified bedside monitoring, clinical exam, and imaging to be useful for evaluating prognosis, whereas fewer considered electrophysiology tests (<60%) and biomarkers (<15%). In a case-based scenario, approximately one-third of respondents agreed, one-third were neutral, and one-third disagreed that the patient prognosis would be unfavorable at one year. About 10% were comfortable recommending withdrawal of life-sustaining therapies. Conclusions:A significant variation in perceptions of neurologic prognosis and in clinical decision making on the level of care was found among Canadian intensivists, neurosurgeons, and neurologists. Improved understanding of the factors that can accurately predict prognosis for patients with traumatic brain injury is urgently needed.

Epidemiology and management of atrial fibrillation in medical and noncardiac surgical adult intensive care unit patients

PURPOSE The aim of the study was to describe the epidemiology and management of atrial fibrillation (AF) in noncardiac surgery critically ill patients in a retrospective, observational study at 3 mixed medical-surgical, university-affiliated intensive care units (ICUs). METHODS Consecutive patients admitted during a 1-year period with any documentation of AF during ICU stay were identified. Demographic data, risk factors, interventions, and outcomes were collected from the medical record. RESULTS A total of 3081 patients were admitted during the 1-year study period in which 348 consecutive patients (10.5%) had documented AF. Atrial fibrillation was of new onset in 139 patients (4.5%) and preexisting in 186 patients (6.0%). Hemodynamic instability developed in 37% and 10% of patients with new-onset AF and patients with preexisting AF, respectively. Most (73%) patients with new-onset AF had at least 1 modifiable risk factor. Pharmacologic rhythm conversion was attempted in 76% and 26% of patients with new-onset AF and patients with preexisting AF, respectively. Although initially successful in 87% of new-onset cases, 42% reverted back to AF. Electrical conversion was successful in 7 (27%) of 26 and 0 (0%) of 5 of patients with new-onset AF and patients with preexisting AF, respectively. In total, 18% and 62% of patients with new-onset AF and patients with preexisting AF, respectively, who survived to ICU discharge left the ICU in AF. CONCLUSIONS Atrial fibrillation is common but transient in most ICU patients. Electrical cardioversion is often unsuccessful, and pharmacologic rhythm conversion is often only transiently effective. Modifiable risk factors are common among these patients. Future studies are needed to address the management of AF in the ICU.

The efficacy and safety of heparin in patients with sepsis: a systematic review and metaanalysis.

Objective:To evaluate the efficacy and safety of heparin in patients with sepsis, septic shock, or disseminated intravascular coagulation associated with infection. Design:Systematic review and metaanalysis. Data Sources:Randomized controlled trials from MEDLINE, EMBASE, CENTRAL, Global Health, Scopus, Web of Science, the International Clinical Trials Registry Platform (inception to April 2014), conference proceedings, and reference lists of relevant articles. Study Selection and Data Extraction:Two reviewers independently identified and extracted trial-level data from randomized trials investigating unfractionated or low molecular heparin administered to patients with sepsis, severe sepsis, septic shock, or disseminated intravascular coagulation associated with infection. Internal validity was assessed in duplicate using the Risk of Bias tool. The strength of evidence was assessed in duplicate using Grading of Recommendations Assessment, Development, and Evaluation methodology. Our primary outcome was mortality. Safety outcomes included hemorrhage, transfusion, and thrombocytopenia. Measurements and Main Results:We included nine trials enrolling 2,637 patients. Eight trials were of unclear risk of bias and one was classified as having low risk of bias. In trials comparing heparin to placebo or usual care, the risk ratio for death associated with heparin was 0.88 (95% CI, 0.77–1.00; I2 = 0%; 2,477 patients; six trials; moderate strength of evidence). In trials comparing heparin to other anticoagulants, the risk ratio for death was 1.30 (95% CI, 0.78–2.18; I2 = 0%; 160 patients; three trials; low strength of evidence). In trials comparing heparin to placebo or usual care, major hemorrhage was not statistically significantly increased (risk ratio, 0.79; 95% CI, 0.53–1.17; I2 = 0%; 2,392 patients; three trials). In one small trial of heparin compared with other anticoagulants, the risk of major hemorrhage was significantly increased (2.14; 95% CI, 1.07–4.30; 48 patients). Important secondary and safety outcomes, including minor bleeding, were sparsely reported. Conclusions:Heparin in patients with sepsis, septic shock, and disseminated intravascular coagulation associated with infection may be associated with decreased mortality; however, the overall impact remains uncertain. Safety outcomes have been underreported and require further study. Increased major bleeding with heparin administration cannot be excluded. Large rigorous randomized trials are needed to evaluate more carefully the efficacy and safety of heparin in patients with sepsis, severe sepsis, and septic shock.

Systematic review of physical and chemical compatibility of commonly used medications administered by continuous infusion in intensive care units

Objective:To quantify the physical and chemical stability data published for commonly used continuously infused medications in the intensive care unit and to evaluate the quality of the studies providing these data. Data Sources and Study Selection:We conducted a systematic electronic literature search of MEDLINE, EMBASE, and International Pharmaceutical Abstracts as well as the references of electronic drug compatibility textbooks for all English and French language research publications evaluating the physical compatibility or chemical stability of the 820 possible two-drug combinations of 41 commonly used drugs in an adult intensive care unit. Data Extraction and Synthesis:A total of 93 studies comprised of 86 (92%) studies evaluating physical compatibility and 35 (38%) studies evaluating chemical compatibility of at least one drug combination of interest were included. Physical and/or chemical compatibility data exist for only 441 of the possible 820 two-drug combinations (54%), whereas chemical compatibility data exist for only 75 (9%) of the possible combinations. Of the 441 combinations for which compatibility data are available, 67 (15%) represent incompatible combinations and 39 (9%) had conflicting data in which both compatible and incompatible data were identified. Conclusions:Physical compatibility studies that provide the basis for y-site compatibility are lacking for commonly used medications in intensive care unit patients and may contribute to unsafe medication practices. Furthermore, the heterogeneity in the methodology of these studies likely contributes to the common finding of conflicting data for specific combinations of drugs. Future studies should apply similar methodologic and reporting principles to be able to reproduce and compare outcomes both clinically and in the laboratory.

Treatment of new-onset atrial fibrillation in noncardiac intensive care unit patients: A systematic review of randomized controlled trials*

Objective:Atrial fibrillation is a common problem associated with morbidity and mortality in critically ill patients; however, evidence-based treatment recommendations are lacking. The objective of this systematic review was to evaluate the efficacy of pharmacologic rhythm control of new-onset atrial fibrillation in noncardiac, critically ill adults. Data Source:Citations identified from an electronic search of Medline, the Cochrane register of controlled trials, and Embase databases (1966 to August 2006) were independently reviewed by two investigators. Study Selection:All prospective randomized controlled trials evaluating pharmacologic rhythm conversion regimens for new-onset atrial fibrillation in (noncardiac surgery) critically ill adult patients were included. The primary end point was atrial fibrillation resolution. Data Extraction:Using a standardized data extraction form, data related to study design, population characteristics, pharmacologic intervention, and outcome measures were collected. Data Synthesis:Four trials met inclusion criteria from 1995 citations screened. Of the 143 evaluable patients in these trials 89 (76%) had atrial fibrillation while the remaining ones had other atrial tachyarrhythmias. Drugs evaluated for rhythm conversion included amiodarone (n = 26), procainamide (n = 14), magnesium (n = 18), flecainide (n = 15), esmolol (n = 28), verapamil (n = 15), and diltiazem (n = 27). The definition of treatment success ranged from conversion within 1 hr to conversion within 24 hrs. No study evaluated maintenance of conversion, and one study included hemodynamically unstable patients. Lack of methodologic homogeneity prevented any pooled analysis. Conclusions:Using the current published literature, we cannot recommend a standard treatment for atrial fibrillation in noncardiac critically ill adult patients. Clinical trials evaluating rhythm conversion in critically ill populations outside of cardiac surgery are lacking. Further trials that address goals of care in hemodynamically stable and unstable patients and utilize standardized definitions of successful cardioversion are required.

Treating an Established Episode of Delirium in Palliative Care: Expert Opinion and Review of the Current Evidence Base With Recommendations for Future Development

CONTEXT Delirium is a highly prevalent complication in patients in palliative care settings, especially in the end-of-life context. OBJECTIVES To review the current evidence base for treating episodes of delirium in palliative care settings and propose a framework for future development. METHODS We combined multidisciplinary input from delirium researchers and other purposely selected stakeholders at an international delirium study planning meeting. This was supplemented by a literature search of multiple databases and relevant reference lists to identify studies regarding therapeutic interventions for delirium. RESULTS The context of delirium management in palliative care is highly variable. The standard management of a delirium episode includes the investigation of precipitating and aggravating factors followed by symptomatic treatment with drug therapy. However, the intensity of this management depends on illness trajectory and goals of care in addition to the local availability of both investigative modalities and therapeutic interventions. Pharmacologically, haloperidol remains the practice standard by consensus for symptomatic control. Dosing schedules are derived from expert opinion and various clinical practice guidelines as evidence-based data from palliative care settings are limited. The commonly used pharmacologic interventions for delirium in this population warrant evaluation in clinical trials to examine dosing and titration regimens, different routes of administration, and safety and efficacy compared with placebo. CONCLUSION Delirium treatment is multidimensional and includes the identification of precipitating and aggravating factors. For symptomatic management, haloperidol remains the practice standard. Further high-quality collaborative research investigating the appropriate treatment of this complex syndrome is needed.