Tony Whitehouse

Vancomycin-associated Nephrotoxicity in the Critically Ill: A Retrospective Multivariate Regression Analysis*

Objectives:To evaluate the influence of vancomycin dose, serum trough concentration, and dosing strategy on the evolution of acute kidney injury in critically ill patients. Design:Retrospective, single-center, observational study. Setting:University Hospital ICU, Birmingham, UK. Patients:All critically ill patients receiving vancomycin from December 1, 2004, to August 31, 2009. Intervention:None. Measurements and Main Results:The prevalence of new onset nephrotoxicity was reported using Risk, Injury, Failure, Loss, End-stage renal disease criteria, and independent factors predictive of nephrotoxicity were identified using logistic regression analysis. Complete data were available for 1,430 patients. Concomitant vasoactive therapy (odds ratio = 1.633; p < 0.001), median serum vancomycin (odds ratio = 1.112; p < 0.001), and duration of therapy (odds ratio = 1.041; p ⩽ 0.001) were significant positive predictors of nephrotoxicity. Intermittent infusion was associated with a significantly greater risk of nephrotoxicity than continuous infusion (odds ratio = 8.204; p ⩽ 0.001). Conclusions:In a large dataset, higher serum vancomycin concentrations and greater duration of therapy are independently associated with increased odds of nephrotoxicity. Furthermore, continuous infusion is associated with a decreased likelihood of nephrotoxicity compared with intermittent infusion. This large dataset supports the use of continuous infusion of vancomycin in critically ill patients.

Enhancing rehabilitation of mechanically ventilated patients in the intensive care unit: A quality improvement project ☆

PURPOSE Prolonged periods of mechanical ventilation are associated with significant physical and psychosocial adverse effects. Despite increasing evidence supporting early rehabilitation strategies, uptake and delivery of such interventions in Europe have been variable. The objective of this study was to evaluate the impact of an early and enhanced rehabilitation program for mechanically ventilated patients in a large tertiary referral, mixed-population intensive care unit (ICU). METHOD A new supportive rehabilitation team was created within the ICU in April 2012, with a focus on promoting early and enhanced rehabilitation for patients at high risk for prolonged ICU and hospital stays. Baseline data on all patients invasively ventilated for at least 5 days in the previous 12 months (n = 290) were compared with all patients ventilated for at least 5 days in the 12 months after the introduction of the rehabilitation team (n = 292). The main outcome measures were mobility level at ICU discharge (assessed via the Manchester Mobility Score), mean ICU, and post-ICU length of stay (LOS), ventilator days, and in-hospital mortality. RESULTS The introduction of the ICU rehabilitation team was associated with a significant increase in mobility at ICU discharge, and this was associated with a significant reduction in ICU LOS (16.9 vs 14.4 days, P = .007), ventilator days (11.7 vs 9.3 days, P < .05), total hospital LOS (35.3 vs 30.1 days, P < .001), and in-hospital mortality (39% vs 28%, P < .05). CONCLUSION A quality improvement strategy to promote early and enhanced rehabilitation within this European ICU improved levels of mobility at critical care discharge, and this was associated with reduced ICU and hospital LOS and reduced days of mechanical ventilation.

Importance of the environment for patient acquisition of methicillin-resistant Staphylococcus aureus in the intensive care unit : A baseline study

Objective:To assess the degree of environmental contamination with methicillin-resistant Staphylococcus aureus (MRSA) in critical care and the likelihood of subsequent new patient acquisition if carriers were or were not moved to single rooms. Design:Randomized sequential sampling of bed areas. Setting:Intensive care units of two teaching hospitals. Patients:Medical and surgical patients requiring critical care. Interventions:Six environmental sites around randomly selected patients plus two communal sites were sampled using contact plates during periods when patients with MRSA were physically isolated or not. Admission, weekly, and discharge screening patient swabs were taken to identify patients admitted with, or newly acquiring, MRSA. Measurements and Main Results:A total of 2,436 samples were taken from environments around 114 patients, plus a further 349 samples from doctors’ hands and telephones. Of the 47 bed areas where MRSA strains were identified that were not found initially on patients, only one patient subsequently acquired the same strain. Five other patients became colonized with new MRSA strains, but these were not found in their environment beforehand. Of 52 patients colonized with MRSA, 34 had a similar strain found subsequently in their environment. Conclusions:Whereas the MRSA-colonized patient frequently contaminates his or her local environment, transmission of MRSA from the environment to the patient was not commonly identified. Studies elucidating possible routes of MRSA transmission are urgently needed to inform infection control policies.

A multicentre randomized controlled trial of moderate hypothermia to prevent intracranial hypertension in acute liver failure

BACKGROUND & AIMS Animal models and human case series of acute liver failure (ALF) suggest moderate hypothermia (MH) to have protective effects against cerebral oedema (CO) development and intracranial hypertension (ICH). However, the optimum temperature for patient management is unknown. In a prospective randomized controlled trial we investigated if maintenance of MH prevented development of ICH in ALF patients at high risk of the complication. METHODS Patients with ALF, high-grade encephalopathy and intracranial pressure (ICP) monitoring in specialist intensive care units were randomized by sealed envelope to targeted temperature management (TTM) groups of 34°C (MH) or 36°C (control) for a period of 72h. Investigators were not blinded to group assignment. The primary outcome was a sustained elevation in ICP >25mmHg, with secondary outcomes the occurrence of predefined serious adverse effects, magnitude of ICP elevations and cerebral and all-cause hospital mortality (with or without transplantation). RESULTS Forty-six patients were randomized, of whom forty-three were studied. There was no significant difference between the TTM groups in the primary outcome during the study period (35% vs. 27%, p=0.56), for the MH (n=17) or control (n=26) groups respectively, relative risk 1.31 (95% CI 0.53-3.2). Groups had similar incidence of adverse events and overall mortality (41% vs. 46%, p=0.75). CONCLUSIONS In patients with ALF at high risk of ICH, MH at 33-34°C did not confer a benefit above management at 36°C in prevention of ICH or in overall survival. This study did not confirm advantage of its prophylactic use. (ISRCTN registration number 74268282; no funding.) LAY SUMMARY Studies in animals with acute liver failure (ALF) have suggested that cooling (hypothermia) could prevent or limit the development of brain swelling, a dangerous complication of the condition. There is limited data on its effects in humans. In a randomized controlled trial in severely ill patients with ALF we compared the effects of different temperatures and found no benefit on improving survival or preventing brain swelling by controlling temperature at 33-34°C against 36°C.

Systematic review of statins in sepsis: There is no evidence of dose response

Objectives: Sepsis is a common cause of morbidity and mortality and is associated with significant costs to the healthcare organizations. We performed a systematic review and meta-analysis to assess whether high or low-dose statin therapy improved mortality in patients with sepsis. Methods: The trials analyzed in this study were multicenter or single center randomized control studies using statins for sepsis in a hospital setting. The patients included were adults with suspected or confirmed infection. Interventions: This study found eight randomized controlled trials where participants were given either a statin or placebo daily for 14–28 days, the duration of their illness, or until their death or discharge, which ever occurred first. Primary and Secondary Outcomes Measured: This meta-analysis measured the effect of statin therapy on in hospital and 28 days mortality. Results: In unselected patients, there was no demonstrable difference in the 28 days mortality (relative risk [RR] 0.88 95% confidence interval [CI], 0.70–1.12 and P = 0.16). There was also no significant difference between statin versus placebo for in-hospital mortality (RR 0.98 95% CI, 0.85–1.14 P = 0.36). When the studies where divided into low-dose and high-dose groups, there were no statistically significant differences for in-hospital mortality between low-dose statin versus placebo for (RR 0.81 CI 0.44–1.49 P = 0.27) or high-dose statin versus placebo (RR 0.99 95% CI 0.85–1.16, P = 0.28). There was no significant difference in adverse effects between the high- and low-dose groups. Conclusions: In this meta-analysis, we found that the use of statins did not significantly improve either in-hospital mortality or 28-day mortality in patients with sepsis. In the low-dose group, there were fewer quality multicenter studies; hence, conclusions based on the results of this subgroup are limited.

Economic impact of Tegaderm chlorhexidine gluconate (CHG) dressing in critically ill patients

Purpose: To estimate the economic impact of a TegadermTM chlorhexidine gluconate (CHG) gel dressing compared with a standard intravenous (i.v.) dressing (defined as non-antimicrobial transparent film dressing), used for insertion site care of short-term central venous and arterial catheters (intravascular catheters) in adult critical care patients using a cost-consequence model populated with data from published sources. Material and Methods: A decision analytical cost-consequence model was developed which assigned each patient with an indwelling intravascular catheter and a standard dressing, a baseline risk of associated dermatitis, local infection at the catheter insertion site and catheter-related bloodstream infections (CRBSI), estimated from published secondary sources. The risks of these events for patients with a Tegaderm CHG were estimated by applying the effectiveness parameters from the clinical review to the baseline risks. Costs were accrued through costs of intervention (i.e. Tegaderm CHG or standard intravenous dressing) and hospital treatment costs depended on whether the patients had local dermatitis, local infection or CRBSI. Total costs were estimated as mean values of 10,000 probabilistic sensitivity analysis (PSA) runs. Results: Tegaderm CHG resulted in an average cost-saving of £77 per patient in an intensive care unit. Tegaderm CHG also has a 98.5% probability of being cost-saving compared to standard i.v. dressings. Conclusions: The analyses suggest that Tegaderm CHG is a cost-saving strategy to reduce CRBSI and the results were robust to sensitivity analyses.

The ageing population is neglected in research studies of traumatic brain injury

Abstract Introduction The UK population is ageing with increasing number of elderly patients suffering traumatic brain injury (TBI). The purpose of this study was to identify national TBI admission demographics, analyse the temporal evolution of TBI mortality in a single centre and conduct a systematic review of the literature to identify whether there is an age bias amongst researchers studying TBI. Methods National demographics for TBI were obtained from Health Episode Statistics. TBI patients admitted from 2000 to 2011 to Cambridge University Hospitals Neurocritical Care Unit (NCCU) were divided into age groups (<60, 60–74, ≥75 years). Temporal evolution of mortality was analysed using a logistic regression method. A systematic literature review was conducted to identify primary TBI research studies. Patient’s ages were extracted and an average mean age was calculated and compared over time. Results From 1998, national TBI admissions have increased with the greatest rise in >60-year age group (p < 0.0001). In a tertiary referral critical care unit (n = 1145), the 60–74 year age group (compared to <60) had a significantly lower improvement in mortality over time (OR: 1.15, 95% CI: 1.02–1.31). A literature review revealed a mean age of 32.73 years (SD ± 12.85) for patients recruited to primary TBI studies. Conclusion Despite increased admissions of elderly patients following TBI and static mortality (single centre, 60–74 year age group) there is little or no evidence of a corresponding increase in the age of patients recruited for TBI studies. In addition to the difficulties this presents in forming evidence-based decisions for the patient with TBI, it may also represent a wider problem for ICU research in an ever-ageing critical care population. More research needs to be conducted to establish the treatment end points for an ageing population.

Is It Time to Beta Block the Septic Patient

Beta blockers are some of the most studied drugs in the pharmacopoeia. They are already widely used in medicine for treating hypertension, chronic heart failure, tachyarrhythmias, and tremor. Whilst their use in the immediate perioperative patient has been questioned, the use of esmolol in the patients with established septic shock has been recently reported to have favourable outcomes. In this paper, we review the role of the adrenergic system in sepsis and the evidence for the use of beta stimulation and beta blockers from animal models to critically ill patients.

Tracheostomy in special groups of critically ill patients: Who, when, and where?

Tracheostomy is one of the most common procedures undertaken in critically ill patients. It offers many theoretical advantages over translaryngeal intubation. Recent evidence in a heterogeneous group of critically ill patients, however, has not demonstrated a benefit for tracheostomy, in terms of mortality, length of stay in Intensive Care Unit (ICU), or incidence of ventilator-associated pneumonia. It may be a beneficial intervention in articular subsets of ICU patients. In this article, we will focus on the evidence for the timing of tracheostomy and its effect on various subgroups of patients in critical care.

Addition of PLA2 to CRP enhances sepsis diagnosis

Letter to the Editor refers to: Fredrikke Christie Knudtzen, Stig Lonberg Nielsen, Kim Oren Gradel, Annmarie Touborg Lassen, Hans Jorn Kolmos, Thoger Gorm Jensen, Pernille Just Vinholt, Court Pedersen, Characteristics of patients with community-acquired bacteremia who have low levels of C-reactive protein (≤20 mg/L), Journal of Infection, Volume 68, Issue 2, February 2014, Pages 149-155