Category Archives: Resus

Life-saving medicine

Out-of hospital traumatic paediatric cardiac arrest

This small study on traumatic arrests in children1 refutes the “100% mortality from traumatic arrest” dogma that people still spout and gives information on the mechanisms associated with survival: drowning and strangulation were associated with greater rates of survival to hospital admission compared with blunt, penetrating, and other traumas. Overall, drowning had the greatest rate of survival to discharge (19.1%).
I would like to know the injuries sustained in non-survivors, to determine whether they were potentially treatable. Strikingly, in the list of prehospital procedures performed, there were NO attempts at pleural decompression, something that is standard in traumatic arrest protocols in prehospital services were I have worked.
It is interesting to compare these results with those of the London HEMS team2, who for traumatic paediatric arrest achieved 19/80 (23.8%) survival to discharged from the emergency department and 7/80 (8.75%) survival to hospital discharge. They also noted a large proportion of the survivors suffered hypoxic or asphyxial injuries, whereas those patients with hypovolaemic cardiac arrest did not survive.


OBJECTIVE:To determine the epidemiology and survival of pediatric out-of-hospital cardiac arrest (OHCA) secondary to trauma.

METHODS:The CanAm Pediatric Cardiac Arrest Study Group is a collaboration of researchers in the United States and Canada sharing a common goal to improve survival outcomes for pediatric cardiac arrest. This was a prospective, multicenter, observational study. Twelve months of consecutive data were collected from emergency medical services (EMS), fire, and inpatient records from 2000 to 2003 for all OHCAs secondary to trauma in patients aged ≤18 years in 36 urban and suburban communities supporting advanced life support (ALS) programs. Eligible patients were apneic and pulseless and received chest compressions in the field. The primary outcome was survival to discharge. Secondary measures included return of spontaneous circulation (ROSC), survival to hospital admission, and 24-hour survival.

RESULTS:The study included 123 patients. The median patient age was 7.3 years (interquartile range [IQR] 6.0-17.0). The patient population was 78.1% male and 59.0% African American, 20.5% Hispanic, and 15.7% white. Most cardiac arrests occurred in residential (47.1%) or street/highway (37.2%) locations. Initial recorded rhythms were asystole (59.3%), pulseless electrical activity (29.1%), and ventricular fibrillation/tachycardia (3.5%). The majority of cardiac arrests were unwitnessed (49.5%), and less than 20% of patients received chest compressions by bystanders. The median (IQR) call-to-arrival interval was 4.9 (3.1-6.5) minutes and the on-scene interval was 12.3 (8.4-18.3) minutes. Blunt and penetrating traumas were the most common mechanisms (34.2% and 25.2%, respectively) and were associated with poor survival to discharge (2.4% and 6.5%, respectively). For all OHCA patients, 19.5% experienced ROSC in the field, 9.8% survived the first 24 hours, and 5.7% survived to discharge. Survivors had triple the rate of bystander cardiopulmonary resuscitation (CPR) than nonsurvivors (42.9% vs. 15.2%). Unlike patients sustaining blunt trauma or strangulation/hanging, most post-cardiac arrest patients who survived the first 24 hours after penetrating trauma or drowning were discharged alive. Drowning (17.1% of cardiac arrests) had the highest survival-to-discharge rate (19.1%).

CONCLUSIONS:The overall survival rate for OHCA in children after trauma was low, but some trauma mechanisms are associated with better survival rates than others. Most OHCA in children is preventable, and education and prevention strategies should focus on those overrepresented populations and high-risk mechanisms to improve mortality.

1. Epidemiology of out-of hospital pediatric cardiac arrest due to trauma
Prehosp Emerg Care, 2012 vol. 16 (2) pp. 230-236
2. Outcome from paediatric cardiac arrest associated with trauma
Resuscitation. 2007 Oct;75(1):29-34

Nitrate bolus in acute heart failure

Despite intravenous nitrate boluses being used in original studies demonstrating benefit in acute heart failure1,2, I regularly meet reluctance from both physicians and nurses in the emergency department to give them.
Their resistance seems to be based on a concern for inducing hypotension, and they prefer to ‘titrate up’ an infusion.
iv nitrate options include nitroglycerin (GTN), and isosorbide dinitrate (ISDN). Studies have used ISDN 4mg every 4 mins, ISDN 3mg every 5 mins, and GTN 2mg every 3 mins3.
There are a number of reasons to avoid starting with a low rate infusion in a sick heart failure patient.
Matthew Reed highlighted cannula size as an important factor4:


If a GTN infusion is commenced at a rate of 1 ml/h, a critically unwell patient with a large cannula—for example, a grey cannula (16G) — will have to wait over 6 min for the drug to enter the body. This compares with 1.5 min for a pink cannula (20G) at the same infusion rate. If a large-diameter cannula is chosen for these patients, then a fast initial infusion rate should also be chosen to ensure that the GTN begins to act quickly.

Alistair Steel subsequently pointed out further reasons to avoid slow infusions5:


(1) mechanical slack within an infusion device may mean an infusion set at 1 ml/h will take many minutes for the driver to contact and advance the syringe plunger. For this reason, infusions should be purged before patient connection.

(2) the pharmacokinetics of the drug should be considered. At low infusion rates it will take significant time for a steady state to be achieved (a drug such as GTN, with a half-life of 2 min, would require 10 min to achieve steady state). For clinical effects to be seen quickly, a bolus should be given before commencing infusions.

(3) the use of 1 ml/h infusions (8 µg/min using a 0.5% solution) may be excessively cautious – the British National Formulary recommends a therapeutic dose range from 10 to 200 µg/min. Furthermore, there is emerging evidence that, when used for decompensated heart failure, higher doses of GTN are associated with more favourable outcomes.

(4) at low infusion rates any obstruction in the intravenous system will take a proportionally longer time to become apparent, as it will take longer for the pressure to build up and trigger the syringe pump’s high pressure alarm.
.

Now a recent study confirms such a regimen can be used safely in the elderly. ISDN 3mg bolus treatment was not associated with higher rates of hypotension in the elderly population treated for heart failure in the emergency department. Despite a small study and a retrospective design, this lends support to the practice of iv bolus nitrate therapy for acute heart failure, even in the elderly.
1. Randomised trial of high-dose isosorbide dinitrate plus low-dose furosemide versus high-dose furosemide plus low-dose isosorbide dinitrate in severe pulmonary oedema
Lancet. 1998 Feb 7;351(9100):389-93
2. High-doses intravenous isosorbide dinitrate is safer and better than Bi-PAP ventilation combined with conventional treatment for severe pulmonary edema
J Am Coll Cardiol. 2000 Sep;36(3):832-7 Free Full Text
3. Managing acute pulmonary oedema with high or standard dose nitrate
Emerg Med J. 2009 May;26(5):357-8
4. Administering a glyceryl trinitrate infusion: big is not always best
Emerg Med J 2007;24:423-424
5. Administering a glyceryl trinitrate infusion: faster is better than slower
Emerg Med J. 2008 Jan;25(1):60
6. Isosorbide dinitrate bolus for heart failure in elderly emergency patients: a retrospective study
Eur J Emerg Med. 2011 Oct;18(5):272-5

Non-invasive BP in shock

In the management of the shocked patient, we sometimes get a little fixated on the need for an arterial line. This is in part due to previous studies suggesting non-invasive blood pressure (NIBP) measurements were inaccurate in the critically ill. This appears no longer to be the case with modern oscillometric devices and carefully chosen cuff sizes. This recent study showed mean arterial pressure (MAP) measured non-invasively from the arm closely correlated with invasive measurements. NIBP was effective at identifying hypotension and recording the response to therapy. Although patients with severe occlusive arterial disease were excluded, the study did include a number of shocked patients on vasoactive therapies.
Systolic and diastolic pressures were not accurate. This should not be surprising since, as the authors explain:
“oscillometric devices directly measure the MAP and only extrapolate systolic arterial pressure and diastolic arterial pressure, using proprietary algorithms”
Thia study suggests that NIBP measurement of MAP from the arm is accurate but, if contraindicated, the ankle (or even the thigh in older sedated patients) may be a suitable alternative site permitting a reliable detection of hypotensive and therapy-responding patients.

OBJECTIVE: In the critically ill, blood pressure measurements mostly rely on automated oscillometric devices pending the intra-arterial catheter insertion or after its removal. If the arms are inaccessible, the cuff is placed at the ankle or the thigh, but this common practice has never been assessed. We evaluated the reliability of noninvasive blood pressure readings at these anatomic sites.
DESIGN: Prospective observational study.
SETTING: Medical-surgical intensive care unit.
PATIENTS: Patients carrying an arterial line with no severe occlusive arterial disease.
INTERVENTION: Each patient underwent a set of three pairs of noninvasive and intra-arterial measurements at each site (arm, ankle, thigh [if Ramsay sedation scale >4]) and, in case of circulatory failure, a second set of measurements after a cardiovascular intervention (volume expansion, change in catecholamine dosage).
MEASUREMENTS AND MAIN RESULTS: In 150 patients, whatever the cuff site, the agreement between invasive and noninvasive readings was markedly higher for mean arterial pressure than for systolic or diastolic pressure. For mean arterial pressure measurement, arm noninvasive blood pressure was reliable (mean bias of 3.4 ± 5.0 mm Hg, lower/upper limit of agreement of -6.3/13.1 mm Hg) contrary to ankle or thigh noninvasive blood pressure (mean bias of 3.1 ± 7.7 mm Hg and 5.7 ± 6.8 mm Hg and lower/upper limits of agreement of -12.1/18.3 mm Hg and -7.7/19.2 mm Hg, respectively). During acute circulatory failure (n = 83), arm noninvasive blood pressure but also ankle and thigh noninvasive blood pressure allowed a reliable detection of 1) invasive mean arterial pressure 10%) increase in invasive mean arterial pressure after a cardiovascular intervention (area under the receiver operating characteristic curve of 0.99 [0.92-1], 0.90 [0.80-0.97], and 0.96 [0.87-0.99], respectively).
CONCLUSION: In our population, arm noninvasive mean arterial pressure readings were accurate. Either the ankle or the thigh may be reliable alternatives, only to detect hypotensive and therapy-responding patients.

Noninvasive monitoring of blood pressure in the critically ill: Reliability according to the cuff site (arm, thigh, or ankle)
Crit Care Med. 2012 Apr;40(4):1207-13

In CPR depth is good, but how deep to compress?

Some defibrillators have accelerometers capable of measuring chest compression depth during CPR. This allowed a study correlating compression depth with survival in out of hospital cardiac arrest.
More than half of patients received less than the 2005 recommended chest compression depth of 38–51 mm and >90% received less than the 2010 recommended depth of >50 mm. There was an inverse relationship between rate and depth, ie. rescuers had a tendency to ‘push hard, push slow’ or ‘push soft, push fast’.
The authors state:
We found an association between adequate compression depth and good outcomes but could not demonstrate that the 2010 recommendations are better than those from 2005. Although we believe that compression depth is an important component of CPR and should be measured routinely during cardiac arrest resuscitation, we believe that the optimal depth is currently unknown.


BACKGROUND: The 2010 international guidelines for cardiopulmonary resuscitation recently recommended an increase in the minimum compression depth from 38 to 50 mm, although there are limited human data to support this. We sought to study patterns of cardiopulmonary resuscitation compression depth and their associations with patient outcomes in out-of-hospital cardiac arrest cases treated by the 2005 guideline standards.

DESIGN: Prospective cohort.

SETTING: Seven U.S. and Canadian urban regions.

PATIENTS: We studied emergency medical services treated out-of-hospital cardiac arrest patients from the Resuscitation Outcomes Consortium Epistry-Cardiac Arrest for whom electronic cardiopulmonary resuscitation compression depth data were available, from May 2006 to June 2009.

MEASUREMENTS: We calculated anterior chest wall depression in millimeters and the period of active cardiopulmonary resuscitation (chest compression fraction) for each minute of cardiopulmonary resuscitation. We controlled for covariates including compression rate and calculated adjusted odds ratios for any return of spontaneous circulation, 1-day survival, and hospital discharge.

MAIN RESULTS: We included 1029 adult patients from seven U.S. and Canadian cities with the following characteristics: Mean age 68 yrs; male 62%; bystander witnessed 40%; bystander cardiopulmonary resuscitation 37%; initial rhythms: Ventricular fibrillation/ventricular tachycardia 24%, pulseless electrical activity 16%, asystole 48%, other nonshockable 12%; outcomes: Return of spontaneous circulation 26%, 1-day survival 18%, discharge 5%. For all patients, median compression rate was 106 per minute, median compression fraction 0.65, and median compression depth 37.3 mm with 52.8% of cases having depth <38 mm and 91.6% having depth <50 mm. We found an inverse association between depth and compression rate ( p < .001). Adjusted odds ratios for all depth measures (mean values, categories, and range) showed strong trends toward better outcomes with increased depth for all three survival measures.
CONCLUSIONS: We found suboptimal compression depth in half of patients by 2005 guideline standards and almost all by 2010 standards as well as an inverse association between compression depth and rate. We found a strong association between survival outcomes and increased compression depth but no clear evidence to support or refute the 2010 recommendations of >50 mm. Although compression depth is an important component of cardiopulmonary resuscitation and should be measured routinely, the most effective depth is currently unknown.

What is the role of chest compression depth during out-of-hospital cardiac arrest resuscitation?
Crit Care Med. 2012 Apr;40(4):1192-8

Intubation of the critically ill in Scotland

Hi folks! Cliff has given me the helm of his blogsite for this week whilst he is teaching prehospital and critical care ultrasound with the Americans at Castlefest 2012
He invited me to write an article on this latest paper in British Journal of Anaesthesia on Scottish ICU audit of emergency tracheal intubation. For those who don’t know, Cliff has a proud Scottish heritage and this paper is a useful audit of his home land’s performance of this critical care intervention. I have done airway audits and this one is quite a reasonable 4 month effort albeit not every ICU in Scotland participated, which is not unusual for those wanting to do these kind of audits. Airway management gets a bit personal and some find review of their emergency airway performance to be confronting. It should not be. Now it’s a fine distinction but its important to be clear on this. A FAILED AIRWAY DOES NOT MEAN YOU ARE A FAILURE!! FAILED OXYGENATION IS ANOTHER STORY….
There are always recurring themes from audits like these and I will highlight a few.
The first and foremost, is the absolutely essential role of capnography for tracheal tube confirmation and monitoring of airway patency and ventilator status. My FDEAR aeromedical intubation audit showed this was an issue of patient safety that should be improved.
This Scottish ICU study revealed that capnography was used in only 54% of emergency intubations despite the vast majority being in hospital locations where such monitoring is available! This is a recurring theme amongst emergency airway audits and coroners reports like this one.
Paradoxically this Scottish audit had a high number of intubating doctors with greater than 24 months of anaesthetic training and one hypothesis I have is that as doctors become more confident in emergency intubations, perhaps less reliance is felt required on monitoring like capnography? In human factors research into anaesthetic related crises, we call this the invulnerability or superman complex : “If I say the tube has gone in, I must be right!”
Secondly, the length of anaesthetic training of the intubating doctor appeared related to overall airway success rates and a low complication rate. There was only one surgical airway required over the 4 month period and 794 recorded intubations. The authors discuss though the potential problems that may face up and coming critical care doctors in the United Kingdom who may not be exposed to terms of anaesthetic training of up to 2 years. My own personal view is that it does not and should not matter where you get your emergency airway training but it should be structured and specific to the work that you are going to do. Learning to do epidural anaesthesia in laboring women might not be so helpful for the bilateral pneumonia swine flu patient with a BMI of 50! And certainly no point learning to use airway equipment that you will rarely or never have available where you normally work!
Thirdly and I find this fascinating having heard talks and debates on this topic by Dr Scott Weingart and Dr Paul Mayo, but in this Scottish paper of bloody sick patients needing intubation, 8% were performed without paralytics at all and overall intubation success and number of attempts were not significantly different compared to the paralytic assisted group. My view is that overall in critically ill patients , paralytics are your friend as these folks need the airway secured, one way or another. However this paper and Dr Mayo’s work certainly demonstrate that sedation only intubation is successful and is a reasonable alternative.
Finally, 61% of these emergency intubations utilized propofol and there was an association with post intubation hypotension (systolic <70mmHg). Ketamine use was low at 3% and I think this just reflects the greater anaesthetic training of the doctors in the study. I am aware Cliff has done a previous podcast rant on Propofol assasins
I don’t want to rant and am not as good at it as Cliff. BUT Choose your poison carefully! This paper reminds us what we all know. The milk of amnesia has issues! Ask the Jackson family!
Anyway that’s enough for this paper. I gotta pick myself off the floor again after listening to Cliff’s propofol rant..
– Dr Minh Le Cong, Royal Flying Doctor Service, Australia

BACKGROUND: Complications associated with tracheal intubation may occur in up to 40% of critically ill patients. Since practice in emergency airway management varies between intensive care units (ICUs) and countries, complication rates may also differ. We undertook a prospective, observational study of tracheal intubation performed by critical care doctors in Scotland to identify practice, complications, and training.
METHODS: For 4 months, we collected data on any intubation performed by doctors working in critical care throughout Scotland except those in patients having elective surgery and those carried out before admission to hospital. We used a standardized data form to collect information on pre-induction physical state and organ support, the doctor carrying out the intubation, the techniques and drugs used, and complications noted.
RESULTS: Data from 794 intubations were analysed. Seventy per cent occurred in ICU and 18% occurred in emergency departments. The first-time intubation success rate was 91%, no patient required more than three attempts at intubation, and one patient required surgical tracheostomy. Severe hypoxaemia ( <80%) occurred in 22%, severe hypotension (systolic arterial pressure <80 mm Hg) in 20%, and oesophageal intubation in 2%. Three-quarters of intubations were performed by doctors with more than 24 months formal anaesthetic training and all but one doctor with <6 months training had senior supervision.
CONCLUSIONS: Tracheal intubation by critical care doctors in Scotland has a higher first-time success rate than described in previous reports of critical care intubation, and technical complications are few. Doctors carrying out intubation had undergone longer formal training in anaesthesia than described previously, and junior trainees are routinely supervised. Despite these good results, further work is necessary to reduce physiological complications and patient morbidity.

Tracheal intubation in the critically ill: a multi-centre national study of practice and complications
Br J Anaesth. 2012 May;108(5):792-9

Extubation guidelines

Tracheal extubation is a high risk procedure in anaesthesia and critical care. Until now most guidelines have focused on intubation, with little to guide the process of extubation. Complications may relate to the following issues:

  • Exaggerated reflexes – laryngospasm (which can lead to both hypoxia and negative pressure pulmonary oedema) and bronchospasm
  • Reduced airway reflexes
  • Dysfunctional laryngeal reflexes
  • Depletion of oxygen stores at extubation
  • Airway injury
  • Physiological compromise in other systems
  • Human factors

The goal is to ensure uninterrupted oxygen delivery to the patient’s lungs, avoid airway stimulation, and have a back-up plan, that would permit ventilation and re-intubation with minimum difficulty and delay should extubation fail.
The Difficult Airway Society has now published guidelines for the management of tracheal extubation, describing four steps:

Step 1: plan extubation.

Step 2: prepare for extubation.

Step 3: perform extubation.

Step 4: post-extubation care: recovery and follow-up.

During step 3, emphasis is on pre-oxygenation, positioning, and suction. This is followed by simultaneous deflation of the tracheal tube cuff and removal of the tube at the peak of a sustained inflation. This generates a passive exhalation, which may assist in the expulsion of secretions and possibly reduce the incidence of laryngospasm and breathholding.
The guideline refers to low-risk and at-risk extubations. ‘Low-risk’ (routine) extubation is characterised by the expectation that reintubation could be managed without difficulty, if required. ‘At-risk’ means the presence of general and/or airway risk factors that suggest that a patient may not be able to maintain his/her own airway after removal of the tracheal tube. ‘At-risk’ extubation is characterised by the concern that airway management may not be straightforward should reintubation be required.
These guidelines are written for the peri-operative patient but the text contains some interesting points that are pertinent to the ED or ICU patient. Some simple algorithms are presented:






Difficult Airway Society Guidelines for the management of tracheal extubation
Anaesthesia. 2012 Mar;67(3):318-40 Free full text

More guidelines from the Difficult Airway Society

Australasian ED Airway Registry

Managing the emergency airway is one of the most important and risky things we do. We have a responsibility to record, monitor, report and improve our performance.
In the US, the National Emergency Airway Registry has been running for over a decade and has significantly contributed to our airway knowledge base.
In the UK, the NAP4 audit provided fascinating and scary insight into complications of emergency airway management.
Pre-hospital registries have been developed, like Minh Le Cong’s Flying Doctor Emergency Airway Registry; and many of us are now contributing to the Airway Management Study in Physician Manned Helicopter Emergency Medical Services (AIRPORT) study.
Now there is an opportunity for Australasian emergency departments to contribute to a national audit.
Dr Toby Fogg FACEM, emergency physician at Royal North Shore Hospital in Sydney, who began the registry, explained in a recent Life in The Fast Lane response:


I have been running an airway registry in the ED at The Royal North Shore Hospital in Sydney for the last 2 years.

I presented the first 18 months of data at the ASM in Sydney last year and I must admit, they showed room for improvement!.

One of the many things we have subsequently done is introduced a Pre Intubation Checklist which I have published, along with our preliminary findings, at www.airwayregistry.org.au.

I am happy for people to download the file and use it as is, or with appropriate modifications.

Furthermore I would love to hear from anyone keen to undertake an Airway Registry in their own ED — a PDF of the data collection form we use is also on the website.

As the authors of the NAP4 study conclude, it is essential we all audit our practice of this potentially high risk procedure.

Dr Toby Fogg uses his C-MAC video laryngoscope to demonstrate the audit form


Background: Successful airway management is one of the cornerstones of care for critically ill or injured patients in the Emergency Department (ED). The risks of intubation are known to be higher in this environment than in the operating theatre (OT) yet there are no published data on airway management in an Australian ED.

Objectives: To describe the practice of intubation in the ED of a tertiary hospital in Australia, with particular emphasis on the number of attempts, adjuncts used, the seniority of staff involved and the rate of complications.

Methods: A prospective, observational study.

Results: Over the 18-month study period, 295 episodes of intubation occurred with a total of 345 attempts. Consultant supervision occurred in 69.8% of cases, registrars made the first attempt at intubation in 57.5% and SRMOs in 31.0% of the patients. 83.7% of the patients were intubated at the first pass with a further 13.0% intubated one the second attempt. This leaves 10 patients (3.4%) that required ≥3 attempts, 4 (1.4%) ≥4 attempts and 1 (0.4%) required a 5th attempt. Difficult laryngoscopy, as defined by Cormack and Lehane grade III or IV, occurred in 24% of the first attempts. Bougies were used in 36% of attempts, whilst a stylet in 35%. Video laryngoscopy was used in 47.5% of attempts. Complications occurred in 28%.

Discussion: The success rate within two attempts is comparable to the anaesthetic literature, and although high, the rate of complications is comparable to data from EDs overseas. The rate of difficult laryngoscopy, however, is surprisingly high. The study has prompted a significant review of airway training and management within the ED at Royal North Shore Hospital and the results of the interventions will be monitored.

The Royal North Shore Hospital Emergency Department Airway Registry. A Prospective Observational Study of Airway Management in a Tertiary Hospital Emergency Department in Sydney, Australia
Annesley N,Vassiliadis J, Kerry Hitos K, Fogg T
Emerg. Med. Australas. 24 (Suppl. 1):27-28

Study authors Toby Fogg and Nick Annesley demonstrate the 'Happiness Triad'

Red cell transfusion guidelines

The AABB (formerly the American Association of Blood Banks has issued guidelines on red blood cell transfusion1, providing some number-based targets which may be helpful for some practitioners or organisations. Editorialist and heavyweight intensivist Jean-Louis Vincent argues for a more individual patient-based assessment2, and highlights some of the weaknesses of existing studies, in particular the often quoted but now fairly old TRICC study3 which suffered from poor recruitment and the possible lack of applicability to modern practice now that leucodepleted products are used.
Prof Vincent states:
Transfusion decisions need to consider individual patient characteristics, including age and the presence of CAD, to estimate a specific patient’s likelihood of benefit from transfusion. The decision to transfuse is too complex and important to be guided by a single number.


Description: Although approximately 85 million units of red blood cells (RBCs) are transfused annually worldwide, transfusion practices vary widely. The AABB (formerly, the American Association of Blood Banks) developed this guideline to provide clinical recommendations about hemoglobin concentration thresholds and other clinical variables that trigger RBC transfusions in hemodynamically stable adults and children.

Methods: These guidelines are based on a systematic review of the literature on randomized clinical trials evaluating transfusion thresholds. We performed a literature search from 1950 to February 2011 with no language restrictions. We examined the proportion of patients who received any RBC transfusion and the number of RBC units transfused to describe the effect of restrictive transfusion strategies on RBC use. To determine the clinical consequences of restrictive transfusion strategies, we examined overall mortality, nonfatal myocardial infarction, cardiac events, pulmonary edema, stroke, thromboembolism, renal failure, infection, hemorrhage, mental confusion, functional recovery, and length of hospital stay.

Recommendation 1: The AABB recommends adhering to a restrictive transfusion strategy (7 to 8 g/dL) in hospitalized, stable patients (Grade: strong recommendation; high-quality evidence).

Recommendation 2: The AABB suggests adhering to a restrictive strategy in hospitalized patients with preexisting cardiovascular disease and considering transfusion for patients with symptoms or a hemoglobin level of 8 g/dL or less (Grade: weak recommendation; moderate-quality evidence).

Recommendation 3: The AABB cannot recommend for or against a liberal or restrictive transfusion threshold for hospitalized, hemodynamically stable patients with the acute coronary syndrome (Grade: uncertain recommendation; very low-quality evidence).

Recommendation 4: The AABB suggests that transfusion decisions be influenced by symptoms as well as hemoglobin concentration (Grade: weak recommendation; low-quality evidence).

1. Red Blood Cell Transfusion: A Clinical Practice Guideline From the AABB
Ann Intern Med. 2012 Mar 26. [Epub ahead of print] Full Text
2. Indications for Blood Transfusions: Too Complex to Base on a Single Number?
Ann Intern Med. 2012 Mar 26. [Epub ahead of print] Full Text
3. A Multicenter, Randomized, Controlled Clinical Trial of Transfusion Requirements in Critical Care
N Engl J Med 1999; 340:409-417 Full Text

International recommendations for lung ultrasound

A multidisciplinary panel of 28 experts from eight countries reviewed the literature and came up with consensus guidelines in point-of-care lung ultrasound. There were some big names involved – all the big players in emergency/critical care ultrasound from around the World. Conspicuously absent were Matt and Mike from the Emergency Ultrasound Podcast, but maybe there was a maximum awesomeness limit or something.

Here are some snippets, taken out of context and without the grade of recommendation attached. Try to get hold of the original if you can, which might not be easy. I never understand it when ‘international recommendations’ are published as subscription-only articles. Either they want people to follow them or not. Oh well – here are some of their recommendations:
Pneumothorax

  • The sonographic signs of pneumothorax include the following: Presence of lung point(s); Absence of lung sliding; Absence of B-lines; Absence of lung pulse
  • The lung pulse refers to the subtle rhythmic movement of the visceral upon the parietal pleura with cardiac oscillations and is a rule-out sign for pneumothorax
  • In the supine patient, the sonographic technique consists of exploration of the least gravitationally dependent areas progressing more laterally.
  • Bedside lung ultrasound is a useful tool to differentiate between small and large pneumothorax, using detection of the lung point.

Interstitial syndrome

  • B-lines are defined as discrete laser-like vertical hyperechoic reverberation artifacts that arise from the pleural line (previously described as ‘‘comet tails’’), extend to the bottom of the screen without fading, and move synchronously with lung sliding.
  • The presence of multiple diffuse bilateral B-lines indicates interstitial syndrome. Causes of interstitial syndrome include the following conditions: Pulmonary edema of various causes; Interstitial pneumonia or pneumonitis; Diffuse parenchymal lung disease (pulmonary fibrosis)

Lung consolidation

  • The sonographic sign of lung consolidation is a subpleural echo-poor region or one with tissue-like echotexture.
  • Lung ultrasound is a clinically useful tool to rule in pneumonia; however, lung ultrasound does not rule out consolidations that do not reach the pleura.
  • In mechanically ventilated patients lung ultrasound should be considered as it is more accurate than portable chest radiography in the detection of consolidation.

Pleural effusion

  • Both of the following signs are present in almost all free effusions: A space (usually anechoic) between the parietal and visceral pleura; Respiratory movement of the lung within the effusion (‘‘sinusoid sign’’)
  • In opacities identified by chest radiography, lung ultrasound should be used because it is more accurate than chest radiography in distinguishing between effusion and consolidation.
  • Visualization of internal echoes, either of mobile particles or septa, is highly suggestive of exudate or hemothorax


BACKGROUND: The purpose of this study is to provide evidence-based and expert consensus recommendations for lung ultrasound with focus on emergency and critical care settings.

METHODS: A multidisciplinary panel of 28 experts from eight countries was involved. Literature was reviewed from January 1966 to June 2011. Consensus members searched multiple databases including Pubmed, Medline, OVID, Embase, and others. The process used to develop these evidence-based recommendations involved two phases: determining the level of quality of evidence and developing the recommendation. The quality of evidence is assessed by the grading of recommendation, assessment, development, and evaluation (GRADE) method. However, the GRADE system does not enforce a specific method on how the panel should reach decisions during the consensus process. Our methodology committee decided to utilize the RAND appropriateness method for panel judgment and decisions/consensus.

RESULTS: Seventy-three proposed statements were examined and discussed in three conferences held in Bologna, Pisa, and Rome. Each conference included two rounds of face-to-face modified Delphi technique. Anonymous panel voting followed each round. The panel did not reach an agreement and therefore did not adopt any recommendations for six statements. Weak/conditional recommendations were made for 2 statements, and strong recommendations were made for the remaining 65 statements. The statements were then recategorized and grouped to their current format. Internal and external peer-review processes took place before submission of the recommendations. Updates will occur at least every 4 years or whenever significant major changes in evidence appear.

CONCLUSIONS: This document reflects the overall results of the first consensus conference on “point-of-care” lung ultrasound. Statements were discussed and elaborated by experts who published the vast majority of papers on clinical use of lung ultrasound in the last 20 years. Recommendations were produced to guide implementation, development, and standardization of lung ultrasound in all relevant settings.

International evidence-based recommendations for point-of-care lung ultrasound
Intensive Care Med. 2012 Apr;38(4):577-91

Spinal imaging for the adult obtunded blunt trauma patient

‘You can’t clear the cervical spine until the patient wakes up!’ How often have you heard this said about a patient with severe traumatic brain injury who may not ‘wake up’ for weeks, if at all?
A controversial area, but many institutions now allow collar removal if a neck CT scan is normal. Does this rule out injury with 100% sensitivity? No – but it probably pushes the balance of risk towards removing the collar – an intervention with no evidence for benefit and plenty of reasons why it may be harmful to ventilated ICU patients. For example, clearing the cervical spine based on MDCT was associated with less delirium and less ventilator associated pneumonia, both of which have been associated with increased mortality in critically ill patients (this is referenced in the paper below).
The UK’s Intensive Care Society has had pragmatic guidelines along these lines since 2005, which can be found here. This month’s Intensive Care Medicine publishes an updated literature review providing some further support to this approach.


PURPOSE: Controversy exists over how to ‘clear’ (we mean enable the clinician to safely remove spinal precautions based on imaging and/or clinical examination) the spine of significant unstable injury among clinically unevaluable obtunded blunt trauma patients (OBTPs). This review provides a clinically relevant update of the available evidence since our last review and practice recommendations in 2004.

METHODS: Medline, Embase. Google Scholar, BestBETs, the trip database, BMJ clinical evidence and the Cochrane library were searched. Bibliographies of relevant studies were reviewed.

RESULTS: Plain radiography has low sensitivity for detecting unstable spinal injuries in OBTPs whereas multidetector-row computerised tomography (MDCT) approaches 100%. Magnetic resonance imaging (MRI) is inferior to MDCT for detecting bony injury but superior for detecting soft tissue injury with a sensitivity approaching 100%, although 40% of such injuries may be stable and ‘false positive’. For studies comparing MDCT with MRI for OBTPs; MRI following ‘normal’ CT may detect up to 7.5% missed injuries with an operative fixation in 0.29% and prolonged collar application in 4.3%. Increasing data is available on the complications associated with prolonged spinal immobilisation among a population where a minority have an actual injury.

CONCLUSIONS: Given the variability of screening performance it remains acceptable for clinicians to clear the spine of OBTPs using MDCT alone or MDCT followed by MRI, with implications to either approach. Ongoing research is needed and suggestions are made regarding this. It is essential clinicians and institutions audit their data to determine their likely screening performances in practice.

Clinical review: spinal imaging for the adult obtunded blunt trauma patient: update from 2004
Intensive Care Med. 2012 Mar 10. [Epub ahead of print]