Evidence-based medicine – are we boiling the frog?

Evidence-based medicine has been defined as ‘The conscientious, explicit and judicious use of current best evidence in making decisions about the care of individual patients.’ There are two major assumptions in this statement. First, it is assumed that the evidence is in fact the best. Unfortunately this is not necessarily so, and published evidence is affected by bias, sponsorship, and blind faith in mathematical probability which may not be clinically relevant. Second, the evidence is population based and may not be applicable to the individual, and blind adherence to this concept may cause harm. We must not abandon clinical experience and judgement in favour of a series of inanimate data points. Medicine is an uncertain science

The wrong and wounding road: Paediatric polytrauma admitted to a level 1 trauma intensive care unit over a 5-year period

Background. Injury in childhood is a major cause of potentially preventable morbidity and mortality. In order to implement effective preventive strategies, epidemiological data on mechanisms of injury and outcome are essential.Objectives. To assess the causation, severity of injury, morbidity and mortality of paediatric trauma admitted to a level 1 trauma intensive care unit (TICU).Methods. Children were defined as being <16 years of age. The study covered the 5-year period January 2008 - December 2012. Eligible patients were identified from a prospective database maintained in the level 1 TICU at Inkosi Albert Luthuli Central Hospital, Durban, South Africa. Data extracted were referral source, mechanism of injury, age and gender distribution, injury severity score (ISS), anatomical distribution of injury and mortality.Results. A total of 181 patients admitted during the study period accounted for 15.9% of all admissions. There were 84 females (46.4%) and 97 males (53.6%), with a median age of 7 years (interquartile range (IQR) 4 - 10). Sources of admission were directly from the scene in 38 cases (21.0%), from a primary healthcare facility in 47 (26.0%), from a regional hospital in 56 (31.0%) and from a tertiary facility in 40 (22.0%). Mortality rates according to location of transfer were regional hospital 8 deaths (30.8%), tertiary facility 7 (26.9%), primary health clinic 7 (26.9%), and from the scene 4 (15.4%). Mechanisms of injury were pedestrian-motor vehicle collision (PMVC) in 105 cases (58.0%), motor vehicle passenger in 38 (21.0%), non-vehicular blunt trauma in 18 (10.0%), gunshot wounds (GSWs) in 12 (6.6%), stab wounds in 6 (3.3%), bull goring in 1 (0.5%) and bicycle accident 1 (0.5%). The median ISS for all admissions was 25 (IQR 16 - 38). ISSs were >25 in 98 patients (54.1%), 16 - 25 in 51 (28.2%), 9 - 15 in 9 (4.9%) and <9 in 13 (7.2%); 61.9% of patients had head injuries, 48.1% injuries to the extremities, 41.4% abdominal trauma, 40.3% thoracic trauma, 20.4% external soft-tissue trauma, 9.9% cervical injury and 9.4% facial trauma. There were 26 deaths (14.4%), of which PMVCs accounted for 16 (61.5%), motor vehicle passengers for 7 (26.9%), blunt trauma for 2 (7.7%) and GSWs for 1 (3.8%). The majority of deaths (92%) were of patients with an ISS >25. Of the 26 patients who died, 88.4% had a head injury, 46.2% an extremity injury, 38.5% an external injury, 34.6% abdominal or chest injuries, 19.2% neck injury and 11.5% facial injury.Conclusions. Motor vehicle-related injuries, especially PMVCs, dominate severe paediatric trauma and there is an urgent need for more road traffic education and stringent measures to decrease the incidence and associated morbidity and mortality

Microbiological surveillance and antimicrobial stewardship minimise the need for ultrabroad-spectrum combination therapy for treatment of nosocomial infections in a trauma intensive care unit: An audit of an evidence-based empiric antimicrobial policy

Background. Nosocomial infections are a major cause of morbidity in the critically injured, and the incidence of resistant strains of bacteria is increasing. Management requires a strategy that achieves accurate empiric cover without antibiotic overuse - a goal that may be achieved by surveillance and antibiotic stewardship.Objectives. With the aim of minimising the use of empirical ultrabroad-spectrum combination antimicrobial prescriptions and reducing bacterial resistance, the level I Trauma Intensive Care Unit (TICU) at Inkosi Albert Luthuli Central Hospital (IALCH) in Durban employs stewardship and an antimicrobial policy based on surveillance. This study was undertaken with three aims: (i) to describe the spectrum and sensitivities of nosocomial pathogens in a level I TICU; (ii) to ascertain, based on surveillance data, how frequently initial empiric choice of antimicrobials was correct; and (iii) to determine how frequently ultrabroad-spectrum antimicrobials were prescribed and were actually necessary.Methods. Over a 12-month period, all critically injured patients who  underwent mechanical ventilation in the TICU were identified from a prospectively gathered database. Information regarding every specimen submitted to the National Health Laboratory Services (NHLS) situated at IALCH was extracted from the laboratory computer database. For each patient, bacterial isolates and antimicrobial susceptibility were identified using standard laboratory techniques. Empiric prescriptions for presumed nosocomial sepsis were identified from the hospital’s computerised patient record system and compared with culture results. Acinetobacter species were regarded as colonisers and treatment not offered unless this was the sole isolate in the presence of signs of severe sepsis.Results. Of 227 patients, 106 (46.6%) had 136 culture-positive isolates with a total of 323 pathogens (201 Gram-negative, 119 Grampositive,3 Candida albicans). There were 19 species of Gram-negative pathogens, of which 56% comprised Enterobacteriaceae. Extended spectrum  beta-lactamase (ESBL) production was found in 6/31 (19%) Escherichia coli coli and 6/24 (25%) Klebsiella isolates. Staphyloccocal species accounted for 60% of the Gram-positive isolates, of which 18 were methicillin-resistant Staphylococcus aureus (MRSA). All Candida isolates were sensitive to fluconazole. One hundred and one empiric and 14 directed prescriptions were issued. Despite positive cultures, antimicrobials were not prescribed for 21 patients who had no evidence of sepsis. Excluding multidrug-resistant Acinetobacter isolates, there were 87 (93.5%) appropriate and 6 (6.5%) incorrect prescriptions. Ultrabroad-spectrum combination therapy (U-bSCT) was employed for 11 patients but was necessary in only 2.Conclusions. When combined with regular bacterial surveillance,  antimicrobial stewardship allows accurate empiric antimicrobial prescription with minimal need for ultrabroad-spectrum combination therapy. This policy can potentially reduce the emergence of multidrug-resistant  pathogens, precluding the need for broad-spectrum antimicrobials and the attendant problems of overuse

Direct admission versus inter-hospital transfer to a level I trauma unit improves survival An audit of the new Inkosi Albert Luthuli Central Hospital trauma unit

Objective. To audit the performance of a new level I trauma unit and trauma intensive care unit. Methods. Data on patients admitted to the level I trauma unit and trauma intensive care unit at Inkosi Albert Luthuli Central Hospital, Durban, from March 2007 to December 2008 were retrieved from the hospital informatics system and an independent database in the trauma unit. Results. Four hundred and seven patients were admitted; 71% of admissions were inter-hospital transfers (IHT) and 29% direct from scene (DIR). The median age was 27 years (range 1 - 83), and 71% were male. Blunt injury accounted for 66.3% of admissions and penetrating trauma for 33.7%. Of the former, motor vehicle-related injury accounted for 87.4%, with 81% of paediatric admissions due to pedestrian-related injuries. The median injury severity score (ISS) for the entire cohort was 22 (survivors 18, deaths 29; p<0.001). Patients in the DIR group had a significantly higher mean ISS compared with the IHT group (DIR 25, IHT 20; p<0.02). The overall mortality rate was 26.3%. There were 37 deaths (31.1%) in the DIR group and 70 (24.3%) in the IHT group (p=0.19). In patients surviving more than 12 hours the overall mortality rate was 21.1% (DIR 13.7%, IHT 23.5%; p=0.042). Conclusions. Trauma is a major cause of premature death in the young. Despite a significantly higher median ISS in direct admissions, there was no difference in mortality. Of those surviving more than 12 hours, patients admitted directly had a significant decrease in mortality. Dedicated trauma units improve outcome in the critically injured

Empirical antimicrobial therapy for probable v. directed therapy for possible ventilator-associated pneumonia in critically injured patients

Background. Ventilator-associated pneumonia (VAP) has recently been classified as possible or probable. Although direct attributable mortality has been difficult to prove, delay in instituting appropriate therapy has been reported to increase morbidity and mortality. Recent literature suggests that in possible VAP, instituting directed therapy while awaiting microbiological culture does not prejudice outcome compared with best-guess empirical therapy.Objectives. To ascertain outcomes of directed v. empirical therapy in possible and probable VAP, respectively. Methods. Endotracheal aspirates were obtained from patients with suspected VAP. Those considered to have possible VAP were given directed therapy following culture results, whereas patients with more convincing evidence of VAP were classed as having probable VAP and commenced on empirical antimicrobials based on microbiological surveillance.Results. Pneumonia was suspected in 106 (36.8%) of 288 patients admitted during January - December 2014. Of these, 13 did not fulfil the criteria for VAP. Of the remaining 93 (32.2%), 31 (33.3%) were considered to have probable and 62 (66.7%) possible VAP. The former were commenced on empirical antimicrobials, with 28 (90.3%) receiving appropriate therapy. Of those with possible VAP, 34 (54.8%) were given directed therapy and in 28 (45.2%) no antimicrobials were prescribed. Of the latter, 24 recovered without antimicrobials and 4 died, 3 from severe traumatic brain injury and 1 due to overwhelming intra-abdominal sepsis. No death was directly attributable to failure to treat VAP. No significant difference in mortality was found between the 34 patients with possible VAP who were commenced on directed therapy and the 31 with probable VAP who were commenced on empirical antimicrobials (p=0.75).Conclusions. Delaying antimicrobial therapy for VAP where clinical doubt exists does not adversely affect outcome. Furthermore, this policy limits the use of antimicrobials in patients with possible VAP following improvement in their clinical condition despite no therapy

Elevated international normalised ratios correlate with severity of injury and outcome

Background. Haemorrhagic shock is the leading cause of preventable early deaths from trauma. Acute coagulopathy on admission to a trauma unit is associated with worse outcomes. The relationship of haemorrhage to early mortality remains consistent regardless of mechanism of injury. Haemorrhage and haemorrhagic shock are increasingly amenable to interventions that result in reductions in morbidity and mortality. Objectives. To assess the prevalence of coagulopathy in patients admitted to the level 1 trauma unit at Inkosi Albert Luthuli Central Hospital, Durban, South Africa, and correlate it with in-hospital mortality. Methods. A retrospective analysis of the first 1 000 patients admitted to the trauma unit during the years 2007 - 2011 was performed. The admission international normalised ratios (INRs) were correlated with Injury Severity Scores (ISSs) and in-hospital mortality. A multivariable Poisson model with robust standard errors was used to assess the relationship between coagulopathy and mortality after adjustment for the confounding influence of age and gender. The data were analysed using the R statistics program. Results. Of the 1 000 patients, 752 were male. There were 261 admissions directly from the scene and 739 inter-hospital transfers (non scene). The mean INRs among survivors for all, scene and non-scene patients were 1.33, 1.30 and 1.34, respectively, and those among non-survivors 1.92, 2.01 and 1.88, respectively (p<0.001). The overall prevalence of coagulopathy was 48.7%, 46.9% in scene patients and 49.2% in non-scene patients. The mortality rate of scene patients with abnormal INR levels was 41.1% (adjusted relative risk (aRR) 3.59, 95% confidence interval (CI) 2.11 - 6.44; p<0.001) v. 25.1% for non-scene patients (aRR 1.67, 95% CI 1.15 - 2.05; p=0.004) (p=0.001). Conclusions. There was a high prevalence of coagulopathy in our study. Raised admission INRs were associated with worse outcomes. There was a direct correlation between the INR and the ISS. INRs may offer predictive capabilities in resource-depleted environments where the ISS is not routinely calculated. Early recognition of acute coagulopathy may help reduce morbidity and mortality

Does severe non-infectious SIRS differ from severe sepsis? Results from a multi-centre Australian and New Zealand intensive care unit study

Objective To compare the time course of organ dysfunction/failure, mortality and cause of death in patients with severe sepsis (SS) and patients with severe non-infectious systemic inflammatory response syndrome (SNISIRS). Design Secondary analysis of a multi-centre inception cohort study. Setting Twenty-three multidisciplinary intensive care units (ICUs) in Australia and New Zealand. Patients and participants 3,543 ICU admissions ≥48 h o