A prospective open label randomised controlled trial from China compared two doses of r-tPA for massive or submassive PE. 50 mg / 2hr was as efficacious as 100 mg / 2hr but had fewer bleeding complications. Bleeding was much more common in patients under 65 kg, suggesting perhaps there should be dose per kg instead of a nice round number?
Efficacy and safety of low dose recombinant tissue-type plasminogen activator for the treatment of acute pulmonary thromboembolism: a randomized, multicenter, controlled trial.
Chest. 2010 Feb;137(2):254-62
Category Archives: All Updates
The right antibiotic in septic shock makes a massive difference
A retrospective review of appropriate vs inappropriate antimicrobial therapy was undertaken in over four thousand septic shock patients from multiple centres. In terms of definitions, the authors state:
“Appropriate antimicrobial therapy was considered to have been initiated if an antimicrobial with in vitro activity appropriate for the isolated pathogen or pathogens (or in the case of culture-negative septic shock, an antimicrobial or antimicrobial agent concordant with accepted international norms for empiric therapy and modified to local flora) was either the first new antimicrobial agent with which therapy was started after the onset of recurrent or persistent hypotension or was initiated within 6 h of the administration of the first new antimicrobial agent. Otherwise, inappropriate therapy was considered to have been initiated.”
The results are striking: survival rates after appropriate and inappropriate initial therapy were 52.0% and 10.3%, respectively (odds ratio [OR], 9.45; 95% CI, 7.74 to 11.54; p < 0.0001).
A multivariable logistic regression analysis of possible factors that may affect outcome showed the appropriateness of the initial antimicrobial therapy remained most strongly associated with outcome (OR, 8.99; 95% CI, 6.60 to 12.23; p < 0.0001) among all the risk factors assessed.
Initiation of Inappropriate Antimicrobial Therapy Results in a Fivefold Reduction of Survival in Human Septic Shock
Chest. 2009 Nov;136(5):1237-48
N.B. This work was done by the same authors who brought us the study that showed the earlier antibiotics were given to hypotensive septic patients, the better the outcome:
Kumar A, Roberts D, Wood KE, et al. Duration of hypotension before initiation of effective antimicrobial therapy is the critical determinant of survival in human septic shock. Crit Care Med 2006; 34:1589-1596
Is ETT muck delaying weaning?
Organised secretions can build up in a tracheal tube. This increases airway resistance so during a spontaneous breathing trial in a patient being considered for extubation the patient may have increased work of breathing and unfairly fail the trial, delaying extubation.
How can you spot it? Increased airways resistance can increase peak airway pressure. However inspiratory plateau pressure will not be affected (obtained by performing an inspiratory hold). Identifying a big difference between peak and plateau pressures should prompt a search for increased airway resistance, which includes a narrowed tracheal tube lumen. The amount of accumulated secretion is not necessarily related to the duration of intubation.
Increases in endotracheal tube resistance are unpredictable relative to duration of intubation
Chest 2009; 136:1006-1013
College of Paramedics stands its ground
Articles in this month’s EMJ demonstrate an interesting conflict within UK pre-hospital care. The Joint Royal Colleges Ambulance Liaison Committee Airway Working Group, heavily represented by anaesthetists, recommend the removal of tracheal intubation from UK paramedic practice. The College of Paramedics reject this recommendation, providing a robust critique of the paper and calling for better evidence before changing current practice. A fascinating read.
A critical reassessment of ambulance service airway management in prehospital care: Joint Royal Colleges Ambulance Liaison Committee Airway Working Group, June 2008
Emerg Med J 2010;27:226-233
Full Text
The College of Paramedics (British Paramedic Association) position paper regarding the Joint Royal Colleges Ambulance Liaison Committee recommendations on paramedic intubation
Emerg Med J 2010;27:167-170
Full Text
Guidelines on penetrating abdominal trauma
The Eastern Association for the Surgery of Trauma has published guidelines on the nonoperative management of penetrating abdominal trauma.
RECOMMENDATIONS
- Patients who are hemodynamically unstable or who have diffuse abdominal tenderness should be taken emergently for laparotomy (level 1).
- Patients who are hemodynamically stable with an unreliable clinical examination (i.e., brain injury, spinal cord injury, intoxication, or need for sedation or anesthesia) should have further diagnostic investigation performed for intraperitoneal injury or undergo exploratory laparotomy (level 1).
- A routine laparotomy is not indicated in hemodynamically stable patients with abdominal stab wounds (SWs) without signs of peritonitis or diffuse abdominal tenderness (away from the wounding site) in centers with surgical expertise (level 2).
- A routine laparotomy is not indicated in hemodynamically stable patients with abdominal gunshot wounds (GSWs) if the wounds are tangential and there are no peritoneal signs (level 2).
- Serial physical examination is reliable in detecting significant injuries after penetrating trauma to the abdomen, if performed by experienced clinicians and preferably by the same team (level 2).
- In patients selected for initial nonoperative management, abdominopelvic CT should be strongly considered as a diagnostic tool to facilitate initial management decisions (level 2).
- Patients with penetrating injury isolated to the right upper quadrant of the abdomen may be managed without laparotomy in the presence of stable vital signs, reliable examination, and minimal to no abdominal tenderness (level 3).
- The majority of patients with penetrating abdominal trauma managed nonoperatively may be discharged after 24 hours of observation in the presence of a reliable abdominal examination and minimal to no abdominal tenderness (level 3).
- Diagnostic laparoscopy may be considered as a tool to evaluate diaphragmatic lacerations and peritoneal penetration (level 2).
Practice Management Guidelines for Selective Nonoperative Management of Penetrating Abdominal Trauma
J Trauma. 2010 Mar;68(3):721-733
WHO Guidelines for Pandemic Influenza A(H1N1) 2009
The World Health Organisation has published updated guidelines on drug treatment of Influenza A(H1N1)2009 and other influenza viruses. Their recommendations are summarised in this table:
Full text of the guidelines is available here
WHO Guidelines for Pharmacological Management of Pandemic Influenza A(H1N1) 2009 and other Influenza Viruses
WHO website
CT cervical spine in obtunded trauma patients
Prolonged collar use and spinal immobilisation in ICU patients can contribute to pressure sores, increased intracranial pressure, venous obstruction, difficulties with airway management, difficulties with central venous access, respiratory complications, and DVT, so a reliable investigation to rule out unstable cervical spine injury is required. Several studies demonstrate the high sensitivity of CT, and now a prospective study from Canada attempts to lend further support to this.
Comparing against their chosen gold standard of dynamic radiography, ie. flexion/extension views (F/E) in 402 patients who received both tests, there was one case of injury detected by F/E but not by CT, leading to quoted sensitivity of 99.75%. However this negative CT turned out to be a reporting error – the scan, which the authors include in their article, was clearly abnormal.
One weakness of this study is that they excluded patients who died on ICU. More worrying are the stats quoted. The authors stat ‘four hundred one patients (99.75%) had normal CT and F-E images facilitating clinical clearance of their C-spine and discontinuation of spinal precautions‘. So in other words, there was only one patient in their series of 402 with an injury (according to the gold standard), and this was missed. The sensitivity is therefore zero percent, not 99.75%. What seems to be a further error is the reporting in a table of 401 patients who had ‘Positive CT and Negative F-E’, which if true, would give a specificty of zero too!
This paper covers an important topic for intensivists but it seems to me to be too flawed to add meaningfully to the existing evidence that necks can be ‘cleared’ by CT in patients without signs of cervical spine injury, in whom it has been said that the risks of prolonged collar use and immobilisation may outweigh the risks of missed cervical injury.
Cervical spine clearance in obtunded blunt trauma patients: a prospective study
J Trauma. 2010 Mar;68(3):576-82
Echo best test for acute LVF in ED
Three diagnostic tests for acute left ventricular heart failure in dyspnoeic patients were compared, with the gold standard being the diagnosis by three independent reviewers (two cardiologists and one respiratory physician) who were blinded to the results of the tests being examined. The tests in question were NT-proBNP, the Boston criteria, and limited echo performed by emergency physicians.
The primary goal of the echo study was the detection of the following echocardiographic variables, expressed as present or absent: reduced LV ejection fraction (LV ejection fraction <50% on subjective visual estimation of the change in LV size between diastole and systole) and the ‘‘restrictive’’ pattern on pulsed Doppler analysis of mitral inflow (using the apical view).
According to the authors, pulsed Doppler analysis of mitral inflow can be described by three patterns: 1) an ‘‘impaired relaxation’’ pattern, suggesting no increase in LV filling pressures; 2) a ‘‘normal’’ or ‘‘normalized’’ pattern; and 3) a restrictive pattern, suggesting an increase in LV filling pressures.
Trained emergency physicians were able to perform EDecho in a median of 4 minutes, obtaining Doppler data in an average of 80% of patients presenting for acute dyspnea. Considering the 125 patients with both EDecho variables available, reduced LV ejection fraction was less accurate than the restrictive mitral pattern for the diagnosis of aLVHF. The restrictive pattern was more sensitive (82%) and specific (90%) than reduced LV ejection fraction and more specific than the Boston criteria and NT-proBNP for the diagnosis of aLVHF. The accuracy of the restrictive pattern in the overall population was 75%, compared with accuracy of 49% for both NT-proBNP and Boston criteria.
Diagnostic accuracy of emergency Doppler echocardiography for identification of acute left ventricular heart failure in patients with acute dyspnea: comparison with Boston criteria and N-terminal prohormone brain natriuretic peptide.
Acad Emerg Med. 2010 Jan;17(1):18-26
Intubation harder on the floor or in an ambulance
An abstract from the The National Association of EMS Physicians® 2010 Scientific Assembly published in a Supplement of Prehospital Emergency Care describes a study comparing cadaveric intubation success rates by paramedics in different positions: on the floor, on an elevated stretcher, and in a simulated ambulance. Despite less experience intubating on an elevated stretcher, the participants had increased first-attempt success in the elevated stretcher position compared with the back of the ambulance and the floor (although in the latter case this lacked statistical significance). Position is everything! In our HEMS service we prefer a lowered stretcher to either on the ground or in the ambulance – it would be nice to see this position studied one day too.
Pre-hospital intubation: patient position does matter
Prehospital Emergency Care 2010;14(Suppl 1):9
LMA for newborn resuscitation
An observational study of near term infants (34 weeks gestation to 36 weeks and 6 days) born in an Italian centre over a 5 year period showed that nearly 10% of near-term infants needed positive pressure ventilation at birth, confirming that this group of patients is more vulnerable than term infants. Most were able to be managed with either bag-mask ventilation (BMV) or with a size 1 laryngeal mask airway (LMA). Of the 86 infants requiring PPV, 36 (41.8%) were managed by LMA, 34 (39.5%) by BMV and 16 (18.6%) by tracheal intubation. Why not slap a tiny LMA on your neonatal resuscitation cart – it could come in handy!
Delivery room resuscitation of near-term infants: role of the laryngeal mask airway
Resuscitation. 2010 Mar;81(3):327-30