Hypophosphatemia in critically ill patients

Purpose

The aim of this study was to assess the association of phosphate concentration with key clinical outcomes in a heterogeneous cohort of critically ill patients.

Materials and Methods

This was a retrospective observational study at a general intensive care unit (ICU) of an Australian university teaching hospital enrolling 2730 adult critically ill patients.

Results

We studied 10?504 phosphate measurements with a mean value of 1.17 mmol/L (measurements every 28.8 hours on average). Hyperphosphatemia (inorganic phosphate [iP] concentration > 1.4 mmol/L) occurred in 45% and hypophosphatemia (iP ≤ 0.6 mmol/L) in 20%. Among patients without any episodes of hyperphosphatemia, patients with at least 1 episode of hypophosphatemia had a higher ICU mortality than those without hypophosphatemia (P = .004). In addition, ICU nonsurvivors had lower minimum phosphate concentrations than did survivors (P = .009). Similar results were seen for hospital mortality. However, on multivariable logistic regression analysis, hypophosphatemia was not independently associated with ICU mortality (adjusted odds ratio, 0.86 [95% confidence interval, 0.66-1.10]; P = .24) and hospital mortality (odds ratio, 0.89 [0.73-1.07]; P = .21). Even when different cutoff points were used for hypophosphatemia (iP ≤ 0.5, 0.4, 0.3, or 0.2 mmol/L), hypophosphatemia was not an independent risk factor for ICU and hospital morality. In addition, timing of onset and duration of hypophosphatemia were not independent risk factor for ICU and hospital mortality.

Conclusions

Hypophosphatemia behaves like a general marker of illness severity and not as an independent predictor of ICU or in-hospital mortality in critically ill patients.     

A carbohydrate-restrictive strategy is safer and as efficient as intensive insulin therapy in critically ill patients

Purpose

The aim of this study is to compare the safety and efficacy of 2 different strategies for glycemic control in critically ill adult patients.

Materials and Methods

A total of 337 patients were randomly assigned to a carbohydrate-restrictive strategy (group 1) through glucose-free venous hydration, hypoglycidic nutritional formula, and subcutaneous insulin if blood glucose level was higher than 180 mg/dL or to strict normalization of blood glucose levels (80-120 mg/dL) with the use of insulin infusion (group 2).

Results

Patients in group 1 (n = 169) received 2 (0-6.5) units of regular insulin per day, whereas patients in group 2 (n = 168) received 52 (35-74.5) units per day (P < .001). The median blood glucose level was 144 mg/dL in group 1 and 133.6 mg/dL in group 2 (P = .003). Hypoglycemia occurred in 6 (3.5%) patients in group 1 and 27 (16%) in group 2 (P < .001) and was an independent risk factor for neurological dysfunction and mortality.

Conclusions

A carbohydrate-restrictive strategy reduced significantly the incidence of hypoglycemia in critically ill patients compared to intensive insulin therapy. Mortality and morbidity were comparable between the 2 groups.     

The impact of frailty in critically ill patients after trauma: A prospective observational study

BackgroundAs our population ages, older adults are increasingly exposed to trauma. Frailty could be a useful measure to identify patients at risk of a poor outcome. This study aimed to determine the impact of frailty in an Australian trauma intensive care unit (ICU) population.MethodsA prospective observational study of critically ill trauma patients ≥50 years of age. Frailty was determined on admission to the ICU using the frailty phenotype. Demographic and hospital data were collected, and patients were followed up at 6 and 12 months. The primary outcome was 12-month mortality, and multiple regression was used to determine associated factors.ResultsOne hundred thirty-eight patients were included, whose mean age was 68 years; 78.2% (108/138) were classified as major trauma (Injury Severity Score >12). Twenty-two percent (30/138) of patients were identified as frail. Patients with frailty were significantly older: however, they were less severely injured and required lower rates of surgical interventions and mechanical ventilation. Frailty was independently associated with mortality at 6 and 12 months (odds ratio: 5.9, 95% confidence interval: 1.9–18.1 and odds ratio: 7.3, 95% confidence interval: 2.5–21.9, respectively). Patients with frailty had lower measures of global functioning (Glasgow Outcome Scale-Extended frail 3 [1–5] vs nonfrail 6 [(5–7], p = 0.002) and health status (Euro Qol 5Q-5D-5L utility score 0.6 [0.5–0.7] vs 0.7 [0.6–0.9], p = 0.02) at 12 months than patients without frailty.ConclusionFrailty is a useful predictor of poor outcomes in critically ill trauma patients.Registration of protocol numberACTRN12615000039583.     

Metoclopramide improves gastric motility in critically ill patients

Objective: To assess the effect of metoclopramide on gastric motility in critically ill patients. Design: Prospective, controlled, single-blind cross-over trial. Setting: A 10-bed general intensive care unit. Patients: Ten critically ill, enterally fed adult patients without renal failure. Interventions: Each patient received enteral feeding with Enrich via a nasogastric tube at 50 ml/h throughout the 5-h study period on two consecutive days. Either normal saline (control) or 10 mg of metoclopramide (treatment) was administered intravenously at the start of the study period in random order with cross-over design. Measurements and results: Gastric motility was measured indirectly by analysis of the absorption over time of 1.5 g of paracetamol administered into the stomach at the start of the study period together with a 100 ml bolus of Enrich feed. The rate of gastric emptying is proportional to the area under the line plot of serum paracetamol concentration against time over 120 min (AUC120). Eight of the ten patients studied showed an increased AUC120 with metoclopramide compared to that with saline. Statistical analysis with the Wilcoxon signed rank test gave a p value of 0.04, indicating a significant increase in gastric emptying following administration of metoclopramide. Conclusions: The administration of intravenous metoclopramide improved gastric emptying in a heterogeneous group of critically ill patients. Metoclopramide is a useful prokinetic drug in this patient population. Final revision received: 18 January 1999 Accepted: 2 March 1999     

Delirium assessment in the critically ill

Objective To compare available instruments for assessing delirium in critically ill adults that have undergone validity testing and provide clinicians with strategies to incorporate these instruments into clinical practice. Design Medline (1966–September 2006) was searched using the key words: delirium, cognitive dysfunction, assessment, intensive care unit, and critical illness to identify assessment tools that have been used to evaluate delirium in critically ill adults. A special emphasis was placed on delirium assessment tools that have been properly validated. Data on how these tools have been adopted into clinical practice as well as strategies for clinicians to improve delirium assessment in the ICU are highlighted. Measurements and results Six delirium assessment instruments including the Cognitive Test for Delirium (CTD), abbreviated CTD, Confusion Assessment Method–ICU, Intensive Care Delirium Screening Checklist, NEECHAM scale, and the Delirium Detection Score were identified. While each of these scales have undergone validation in critically ill adults, substantial differences exist among the scales in terms of the quality and extent of the validation effort, the specific components of the delirium syndrome each address, their ability to identify hypoactive delirium, their use in patients with a compromised level of consciousness, and their ease of use. Conclusions Incorporation of delirium assessment into clinical practice in the intensive care unit using a validated tool may improve patient care. Clinicians can adopt a number of different strategies to overcome the many barriers associated with routine delirium assessment in the ICU.     

The diagnosis of myocardial infarction in critically ill patients: An agreement study

Purpose

The aim of the study was to assess agreement among 4 intensivists in diagnosing myocardial infarction (MI) in critically ill patients based on screening electrocardiograms (ECGs) and cardiac troponin (cTn) levels.

Methods

Consecutive patients admitted to a medical-surgical intensive care unit (ICU) underwent systematic screening with 12-lead ECGs and cTn measurements throughout their ICU stay. Independently, 4 raters interpreted the ECGs assessing for changes indicative of ischemia and then classified each patient as to whether they met diagnostic criteria for MI based on the screening cTn measurements and ECG results. A priori, 2 raters were designated the primary adjudicators, and their consensus was used as the reference for the agreement statistics. Agreement on MI diagnosis was calculated for the 4 raters and expressed as raw agreement, κ (chance-corrected agreement) and ? (chance-independent agreement, calculated using pairs).

Results

Among 103 enrolled patients, 37 (35.9%) had MI according to the primary adjudicators. The raw agreement for diagnosing MI was 79% (substantial), κ was 0.24 (fair), and ? ranged from 0.12 to 0.73 (slight to substantial).

Conclusions

Diagnosing MI in the ICU remains a challenge due to variable agreement in 12-lead ECG interpretation. Such variation in practice may contribute to underrecognition of MI during critical illness.     

Validation of the multiple organ dysfunction (MOD) score in critically ill medical and surgical patients

Objective To validate the Multiple Organ Dysfunction (MOD) score externally.Design Prospective observational cohort study.Setting Mixed medical/surgical ICU in a tertiary referral university hospital.Patients and participants Thousand eight hundred and nine patients admitted to ICU for more than 24 h over a 3-year period.Interventions None.Measurements and results The MOD score was calculated daily for all patients. The criterion validity of the individual organ scores, the maximal MOD score and the change in MOD score were assessed by examining the relationship between increasing scores and ICU mortality. Increased maximal MOD scores and each of the six individual organ scores, and change in MOD scores were associated with increased mortality.Conclusions Maximal and individual organ scores have criterion validity when tested in a different ICU from that in which the scores were derived, indicating that the scoring systems are reproducible. The association of change in MOD score with mortality indicates that the score is responsive. These data, combined with previous data establishing concept and content validity, indicate that the MOD score is a valid measure of multi-organ dysfunction.     

Predictors of short-term mortality in critically ill patients with solid malignancies

Admission of cancer patients with serious medical complications to the ICU remains controversial primarily because of the high short-term mortality rates in these patients. However, the cancer patient population is heterogeneous regarding age, underlying conditions, and curability of their disease, suggesting that large variations may occur in the effectiveness of intensive care within this subgroup of critically ill patients.¶Objectives: To identify factors predicting 30-day mortality in patients with solid tumors admitted to a medical ICU.¶Patients and methods: We conducted a retrospective study in 120 consecutive cancer patients (excluding patients with hematological malignancies) admitted to the medical ICU of a 650-bed university hospital between January 1990 and July 1997. Medical history, physical and laboratory test findings at admission, and therapeutic interventions within the first 24 h in the ICU were recorded. The study endpoint was vital status 30 days after ICU admission. Stepwise logistic regression was used to identify independent prognostic factors.¶Results: The observed 30-day mortality rate was 58.7 % (n = 68), with most deaths (92 %) occurring in the ICU. Univariate predictors of 30-day mortality were either protective [prior surgery for the cancer (p = 0.01) and complete remission (p = 0.01)] or associated with higher mortality [Knaus scale C or D (p = 0.02), shock (p = 0.04), need for vasopressors (p = 0.0006) or for mechanical ventilation (p = 0.0001), SAPS II score greater than 36 (p = 0.0001), LOD score greater than 6 (p = 0.0001), and ODIN score > 2 (p = 0.0001)]. Three variables were independent predictors: previous surgery for the cancer (OR 0.20, 95 % CI 0.07–0.58), LOD score > 6 (OR 1.26, 95 % CI 1.09–1.44), and need for mechanical ventilation (OR 3.55, 95 % CI; 1.26–6.7). Variables previously thought to be indicative of a poor prognosis (i. e., advanced age, metastatic or progressive disease, neutropenia or bone marrow transplantation) were not predictive of outcome.¶Conclusion: When transfer to an ICU is considered an option by patients and physicians, 30-day mortality is better estimated by an evaluation of acute organ dysfunction than by the characteristics of the underlying malignancy.     

Light and darkness fail to regulate melatonin release in critically ill humans

Objective Pineal dysfunction has been associated with morbidity and mortality in various animal models of severe illness, and low melatonin plasma concentrations have recently been reported in patients on the ICU. However, it is not known whether the physiological response of the pineal gland to light and darkness is preserved in critical illness. Design and patients We examined the nocturnal release of melatonin in response to 1 h of darkness followed by 1 h of bright light (> 10,000 lux) in 20 severely ill patients on a medical ICU. Eleven elderly (median age 73 years) and 9 young patients (38 years) were recruited. Melatonin plasma concentrations were measured at 30-min intervals. Results In 15 patients melatonin plasma concentration was low and responded to neither darkness nor light. In three elderly and two young patients melatonin plasma concentrations were elevated irrespective of illumination. Conclusions The physiological regulation of melatonin secretion by darkness and light is abolished in severely ill patients.     

红细胞分布宽度与危重症患者病死率的相关性研究

目的探讨危重症患者入重症监护室(intensive care unit,ICU)时红细胞分布宽度(red cell distribution width,RDW)与病死率的相关性。方法采用回顾性队列研究,纳入美国重症监护数据库Ⅱ版本2.6(Multiparameter Intelligent Monitoring in Intensive CareⅡversion 2.6,MIMIC-Ⅱv2.6)中单次入院且ICU住院时长> 24 h,同时有RDW检测记录的成年患者。根据RDW预测病死率的最佳cut-off值(14.55%)将研究对象分为低RDW组(RDW <14.55%)及高RDW组(RDW≥14.55%),比较两组的病死率,进一步使用单因素及多因素Logistic回归和Cox回归分析评估RDW与病死率的关系。结果本研究最终共有13 822例患者入组。高RDW组的医院病死率、ICU病死率、28 d病死率及1年病死率均高于低RDW组(分别为19.73%vs.8.42%,15.04%vs.6.65%,22.68%vs.9.12%,36.22%vs.14.45%,均P <0.001)。RDW作为连续变量,多因素分析结果显示,RDW越高,医院病死率(OR=1.227,95%CI 1.190~1.265)、ICU病死率(OR=1.180,95%CI 1.141~1.220)、28 d病死率(HR=1.161,95%CI 1.138~1.185)和1年病死率(HR=1.177,95%CI 1.159~1.195)越高。分组后回归分析结果显示,与低水平RDW组相比,高水平RDW组患者的医院病死率增加0.912倍(OR=1.912,95%CI 1.683~2.172),ICU病死率增加0.673倍(OR=1.673,95%CI 1.452~1.928),28 d病死率增加0.850倍(HR=1.850,95%CI 1.675~2.043),1年病死率增加1.045倍(HR=2.045,95%CI 1.891~2.212),且存在统计学意义(P <0.001)。结论入ICU首次RDW增高是危重症患者死亡的危险因素。     

Inadvertent hypothermia and mortality in critically ill adults: Systematic review and meta-analysis

Objective

Considering that inadvertent hypothermia (IH) is common in Intensive Care Unit (ICU) patients and can be followed by severe complications, this systematic review identified, appraised and synthesised the published literature about the association between IH and mortality in adults admitted to the ICU.

Feasibility of neuromuscular electrical stimulation in critically ill patients

Objective

Critically ill patients often develop intensive care unit–acquired weakness. Reduction in muscle mass and muscle strength occurs early after admission to the intensive care unit (ICU). Although early active muscle training could attenuate this intensive care unit–acquired weakness, in the early phase of critical illness, a large proportion of patients are unable to participate in any active mobilization. Neuromuscular electrical stimulation (NMES) could be an alternative strategy for muscle training. The aim of this study was to investigate the safety and feasibility of NMES in critically ill patients.

Design

This is an observational study.

Setting

The setting is in the medical and surgical ICUs of a tertiary referral university hospital.

Patients

Fifty patients with a prognosticated prolonged stay of at least 6 days were included on day 3 to 5 of their ICU stay. Patients with preexisting neuromuscular disorders and patients with musculoskeletal conditions limiting quadriceps contraction were excluded.

Intervention

Twenty-five minutes of simultaneous bilateral NMES of the quadriceps femoris muscle. This intervention was performed 5 days per week (Monday-Friday). Effective muscle stimulation was defined as a palpable and visible contraction (partial or full muscle bulk).

Measurements

The following parameters, potentially affecting contraction upon NMES, were assessed: functional status before admission to the ICU (Barthel index), type and severity of illness (Acute Physiology And Chronic Health Evaluation II score and sepsis), treatments possibly influencing the muscle contraction (corticosteroids, vasopressors, inotropes, aminoglycosides, and neuromuscular blocking agents), level of consciousness (Glasgow Coma Scale, score on 5 standardized questions evaluating awakening, and sedation agitation scale), characteristics of stimulation (intensity of the NMES, number of sessions per patient, and edema), and neuromuscular electrophysiologic characteristics. Changes in heart rate, blood pressure, oxygen saturation, respiratory rate, and skin reactions were registered to assess the safety of the technique.

Results

In 50% of the patients, an adequate quadriceps contraction was obtained in at least 75% of the NMES sessions. Univariate analysis showed that lower limb edema (P < .001), sepsis (P = .008), admission to the medical ICU (P = .041), and treatment with vasopressors (P = .011) were associated with impaired quadriceps contraction. A backward multivariate analysis identified presence of sepsis, lower limb edema, and use of vasopressors as independent predictors of impaired quadriceps contraction (R² = 59.5%). Patients responded better to NMES in the beginning of their ICU stay in comparison with after 1 week of ICU stay. There was no change in any of the safety end points with NMES.

Conclusions

Critically ill patients having sepsis, edema, or receiving vasopressors were less likely to respond to NMES with an adequate quadriceps contraction. Neuromuscular electrical stimulation is a safe intervention to be administered in the ICU.     

Safety of physical therapy interventions in critically ill patients: A single-center prospective evaluation of 1110 intensive care unit admissions

Purpose

Critical illness survivors commonly have impaired physical functioning. Physical therapy interventions delivered in the intensive care unit can reduce these impairments, but the safety of such interventions within routine clinical practice requires greater investigation.

Materials and Methods

We conducted a prospective observational study of routine physical therapy from July 2009 through December 2011 in the Johns Hopkins Hospital Medical Intensive Care Unit in Baltimore, MD. The incidence of 12 types of physiological abnormalities and potential safety events associated with physical therapy were monitored and evaluated for any additional treatment, cost, or length of stay.

Results

Of 1787 admissions of at least 24 hours, 1110 (62%) participated in 5267 physical therapy sessions conducted by 10 different physical therapists on 4580 patient-days. A total of 34 (0.6%) sessions had a physiological abnormality or potential safety event, with the most common being arrhythmia (10 occurrences, 0.2%) and mean arterial pressure greater than 140 mm Hg (8 occurrences; 0.2%) and less than 55 mm Hg (5 occurrences; 0.1%). Only 4 occurrences (0.1%) required minimal additional treatment or cost, without additional length of stay.

Conclusions

In this large, single-center study, routine care physical therapy interventions were safe for critically ill patients.     

Early versus late intravenous insulin administration in critically ill patients

Objective To investigate whether timing of intensive insulin therapy (IIT) after intensive care unit (ICU) admission influences outcome. Design and setting Single-center prospective cohort study in the 14-bed medical ICU of a 1,171-bed tertiary teaching hospital. Patients The study included 127 patients started on ITT within 48 h of ICU admission (early group) and 51 started on ITT thereafter (late group); the groups did not differ in age, gender, race, BMI, APACHE III, ICU steroid use, admission diagnosis, or underlying comorbidities. Measurements and results The early group had more ventilator-free days in the first 28 days after ICU admission (median 12 days, IQR 0–24, vs. 1 day, 0–11), shorter ICU stay (6 days, IQR 3–11, vs. 11 days, vs. 7–17), shorter hospital stay (15 days, IQR 9–30, vs. 25 days, 13–43), lower ICU mortality (OR 0.48), and lower hospital mortality (OR 0.27). On multivariate analysis, early therapy was still associated with decreased hospital mortality (OR_adj 0.29). The strength and direction of association favoring early IIT was consistent after propensity score modeling regardless of method used for analysis. Conclusions Early IIT was associated with better outcomes. Our results raise questions about the assumption that delayed administration of IIT has the same benefit as early therapy. A randomized study is needed to determine the optimal timing of therapy. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. M.N.G. was supported by K23 HL60710, RO1 HL084060, and RO1 HL60710.     

The association between primary language spoken and all-cause mortality in critically ill patients

Purpose

The study objective was to investigate the association between primary language spoken and all-cause mortality in critically ill patients.

Materials and Methods

We performed a cohort study on 48?581 patients 18 years or older who received critical care between 1997 and 2007 in 2 Boston hospitals. The exposure of interest was primary language spoken determined by the patient or family members who interacted with administrative staff during hospital registration. The primary outcome was 30-day mortality. Associations between language and mortality were estimated by bivariable and multivariable logistic regression models with inclusion of covariate terms thought to plausibly interact with both language and mortality. Adjustment included age, race, sex, Deyo-Charlson index, patient type (medical vs surgical), sepsis, creatinine, hematocrit, white blood count, and number of organs with acute failure.

Results

Validation showed that primary language spoken was highly accurate for a statement in the medical record noting the language spoken that matched the assigned language. Patients whose primary language spoken was not English had improved outcomes (odds ratio 30-day mortality, 0.69 [95% confidence interval, 0.60-0.81; P < .001), relative to patients with English as the primary language spoken, fully adjusted. Similar significant associations are seen with death by days 90 and 365 as well as in-hospital mortality. The improved survival in patients with a non-English primary language spoken is not confounded by indicators of severity of disease and is independent of the specific language spoken and neighborhood poverty rate, a proxy for socioeconomic status. There are significant limitations inherent to large database studies that we have acknowledged and addressed with controlling for measured confounding and evaluation of effect modification.

Conclusions

In a regional cohort, not speaking English as a primary language is associated with improved outcomes after critical care. Our observations may have clinical relevance and illustrate the intersection of several factors in critical illness outcome including severity of illness, comorbidity, and social and economic factors.     

Mean glucose level is not an independent risk factor for mortality in mixed ICU patients

Objective To find out if there is an association between hyperglycaemia and mortality in mixed ICU patients. Design and setting Retrospective cohort study over a 2-year period at the medical ICU of a university hospital. Measurements Admission glucose, maximum and mean glucose, length of stay, mortality, insulin therapy and Apache-II score. Results In 1085 consecutive patients, ICU- and hospital mortality were 20 and 25%, respectively. The total number of blood glucose measurements was 10.012. Admission glucose was 7.9 ± 4.5 mmol/l (mean ± SD), mean glucose 7.5 ± 2.9 and maximum glucose 10.0 ± 5.4 mmol/l. Median ICU length of stay (LOS) was 3.0 days (range 2.0–6.0 days, IQR), and hospital LOS was 16 days (range 7–32 days). In 28% of patients insulin treatment was started. Median Apache-II score was 13. 68% of patients were mechanically ventilated. Univariate analysis showed an association with ICU mortality for mean glucose (non-survivors 8.6 ± 4.3 vs 7.2 ± 2.4 survivors), maximum glucose (11.7 ± 5.9 vs 9.6 ± 5.2, non-survivors vs survivors, respectively), use of insulin (mortality 29 vs 17% in patients not using insulin) and age (61 vs 55.7 years). Gender and a history of diabetes mellitus were not associated with mortality. In a multivariate model, the Apache-II score was the only variable associated with mortality independent of other variables, including mean blood glucose. Conclusion In this retrospective study mean glucose level was not an independent risk factor for mortality in mixed ICU patients.     

Comparison of two frailty identification tools for critically ill patients: A post-hoc analysis of a multicenter prospective cohort study

PurposeWe aimed to describe the association of two frailty screening tools, the validated Clinical Frailty Scale (CFS) score and the recently described modified Frailty Index (mFI) in critically ill patients.Materials and methodsWe performed a post-hoc analysis of a multicenter cohort of patients admitted to six Canadian Intensive Care Units (ICU) between 2010 and 2011. Frailty was screened using the CFS and the mFI. Concordance between these tools was evaluated, as well as discrimination and predictive ability for clinical outcomes after adjustments.ResultsThe cohort included 421 patients. Prevalence of frailty was 32.8% with the CFS and 39.2% with the mFI. However, concordance between the two tools was low [(intraclass correlation of 0.37; 95% confidence interval [CI] 0.29–0.45) and partial Spearman rank correlation of 0.38 (95% CI 0.29–0.47)]. Hospital and 1-year mortality, as well as dependency after discharge and hospital readmission, were greater for frail compared to non-frail patients screened with the use of both tools.ConclusionWhile the CFS and mFI showed low concordance, both showed good discrimination and predictive validity for hospital mortality. Both tools identify a subgroup of frail patients more likely to have worse clinical outcomes.     

Duration of red blood cells storage and outcome in critically ill patients

Purpose

There is conflicting evidence on the effect of red blood cells (RBC) storage duration and clinical outcomes. We aimed to investigate the association between RBC storage duration and clinical outcomes in patients admitted to the intensive care unit (ICU).

Materials and Methods

We retrospectively (2001-2011) studied adults admitted to the ICUs of 2 hospitals who received RBC. Using the mean, maximum and minimum age of RBC units transfused, we evaluated the association between RBC storage duration and mortality. We also analyzed the association between mean age of RBC units and length of stay (LOS) in survivors. We performed sensitivity analyses in patients who only received RBC in ICU and who only received leukodepleted RBC.

Results

We studied 8416 patients who received a median of 4 (interquartile range, 2-7) RBC units. After multivariate analysis, age of RBC was not independently associated with mortality, including in the subgroup analyses. Furthermore, there was no clinically relevant relationship between mean RBC age and LOS.

Conclusions

RBC storage duration was not associated with increased mortality nor ICU and hospital LOS. These results support the view that the effect of RBC storage duration on outcomes in critically ill patients is uncertain.