Comments Off on International recommendations for lung ultrasound
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:
- 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.
- 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)
- 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.
- 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
Flying doctor and airway fanatic Minh Le Cong sent me this poem. It’s based on the Rifleman’s creed of the United States Marine Corps.
It reminded me a bit of my wedding in 2005, when my pre-hospital colleagues surprised us with a guard of honour, holding up laryngoscopes, Magill’s forceps, tracheal tubes, and other airway paraphernalia.
Comments Off on 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]
A nice study reminds of us the option of awake video laryngoscopy as an alternative to fibreoptic instrumentation of the airway. The study was done on healthy volunteers so we have no idea of the applicability to the patient group we would be interested in using this on – those with an anticipated difficult airway sufficiently stable to allow tolerance and preparation for this procedure. The videolaryngoscopy was performed with patients upright in a face-to-face position, with the laryngoscope inserted in the inverted handle-down (“tomahawk”) position (this is the way I remove fishbones using a direct laryngoscope and Magill’s forceps).
Visualization was faster with video laryngoscopy, and grade of view was similar in both groups. Cormack Lehane grading was used to assess view, whereas the POGO score (percentage of glottic opening) might have provided a better means of assessing which view is superior. The study did not evaluate endotracheal tube insertion.
Local anaesthesia was provided with 5 ml nebulised 4% lidocaine and weight-based doses of 4% lidocaine were then sprayed into the nose and oropharynx through a mucosal atomisation device to a maximum of 9 mg/kg. Oxymetazoline was applied nasally for the flexible fibreoptic laryngoscopy.
Study objectives: We compare laryngoscopic quality and time to highest-grade view between a face-to-face approach with the GlideScope and traditional flexible fiber-optic laryngoscopy in awake, upright volunteers.
Methods: This was a prospective, randomized, crossover study in which we performed awake laryngoscopy under local anesthesia on 23 healthy volunteers, using both a GlideScope video laryngoscopy face-to-face technique with the blade held upside down and flexible fiber-optic laryngoscopy. Operator reports of Cormack-Lehane laryngoscopic views and video-reviewed time to highest-grade view, as well as number of attempts, were recorded.
Results: Ten women and 13 men participated. A grade II or better view was obtained with GlideScope video laryngoscopy in 22 of 23 (95.6%) participants and in 23 of 23 (100%) participants with flexible fiber-optic laryngoscopy (relative risk GlideScope video laryngoscopy versus flexible fiber-optic laryngoscopy 0.96; 95% confidence interval 0.88 to 1.04). Median time to highest-grade view for GlideScope video laryngoscopy was 16 seconds (interquartile range 9 to 34) versus 51 seconds (interquartile range 35 to 96) for flexible fiber-optic laryngoscopy. A distribution of interindividual differences demonstrated that GlideScope video laryngoscopy was, on average, 39 seconds faster than flexible fiber-optic laryngoscopy (95% confidence interval 0.2 to 76.9 seconds).
Conclusion: GlideScope video laryngoscopy can be used to obtain a Cormack-Lehane grade II or better view in the majority of awake, healthy volunteers when an upright face-to-face approach is used and was slightly faster than traditional flexible fiber-optic laryngoscopy. However, flexible fiber-optic laryngoscopy may be more reliable
at obtaining high-grade views of the larynx. Awake, face-to-face GlideScope use may offer an alternative approach to the difficulty airway, particularly among providers uncomfortable with flexible fiber-optic laryngoscopy.
GlideScope Versus Flexible Fiber Optic for Awake Upright Laryngoscopy
Ann Emerg Med. 2012 Mar;59(3):159-64
I had the honour of attending trauma rounds with leading South African trauma surgeons today at Groote Schuur Hospital in Cape Town. This was the first day of an intense week-long trauma education tour that I have organised for myself and three of my Sydney HEMS colleagues.
A technique for haemorrhage control in penetrating trauma is to place a Foley catheter (FC) in the wound and inflate the balloon to try to achieve compression of bleeding vascular structures. This has been life-saving in many cases and buys time to get the patient to a trauma or vascular surgeon or in some cases an interventional radiologist.
First described by Gilroy and colleagues from Baragwanath Hospital in Johannesburg1, another, larger case series was subsequently reported by Cape Town’s Navsaria2, the Professor who conducted today’s trauma round I attended. In his paper he describes:
An 18- or 20-G FC was introduced into the bleeding neck wound. An attempt was made to follow the wound tract. The balloon was inflated with 5 ml of water or until resistance was felt. The FC was either clamped or knotted on itself to prevent bleeding through the lumen. The neck wound was sutured in two layers around the catheter. Continued bleeding around the catheter was an indication to proceed to surgery.
There were no deaths attributable to the use of FC balloon tamponade.
Prof. Navsaria describes the following algorithm for the subsequent investigation and management of these patients:
I’ve been teaching this technique as an option in penetrating trauma for a few years but have never actually done it for real. Nice to finally see examples of its successful implementation by people who do this all the time. I’ve seen four patients with Foleys sticking out of their necks in the first 24 hours of being here.
1. Control of life-threatening haemorrhage from the neck: a new indication for balloon tamponade.
We report the use of a Foley catheter, placed through the wound, to provide balloon tamponade of major bleeding from the neck and supraclavicular fossae. In 10 consecutive explorations for exsanguinating injury in these regions balloon tamponade was used eight times, and was judged to be fully effective in four patients, partly effective in one, and ineffective in three patients.
2. Foley catheter balloon tamponade for life-threatening hemorrhage in penetrating neck trauma
World J Surg. 2006 Jul;30(7):1265-8
BACKGROUND: Foley catheter (FC) balloon tamponade is a well-recognized technique employed to arrest hemorrhage from penetrating wounds. The aim of this study was to review our experience with this technique in penetrating neck wounds and to propose a management algorithm for patients with successful FC tamponade.
METHODS: A retrospective chart review (July 2004-June 2005 inclusive) was performed of patients identified from a prospectively collected penetrating neck injury computer database in whom FC balloon tamponade was used. The units’ policy for penetrating neck injuries is one of selective nonoperative management. All patients with successful FC tamponade underwent angiography. A venous injury was diagnosed if angiography was normal. Ancillary tests were performed as indicated. Removal of the FC was performed in the OR.
RESULTS: During the study period, 220 patients with penetrating neck injuries were admitted to our unit. Foley catheter balloon tamponade was used in 18 patients and was successful in 17 patients. Angiography was positive in 3 patients, all of whom underwent surgery. The FC was successfully removed in 13 patients at a mean of 72 (range 48-96) hours. One patient bled after removal of the catheter, mandating emergency surgery.
CONCLUSION: Foley catheter balloon tamponade remains a useful adjunct in the management of selective patients with penetrating, bleeding neck wounds.
Comments Off on Phentolamine for neurogenic pulmonary oedema
A patient with acute intracerebral haemorrhage developed hyoxaemia due to neurogenic pulmonary oedema, accompanied by a labile blood pressure and elevated catecholamine levels.
Nicardipine and other antihypertensive agents including metoprolol, hydralazine, and labetalol were tried without benefit, and the patient continued to deteriorate.
Phentolamine was tried. The introduction, withdrawal, and reintroduction of phentolamine and the clinical status of the patient is described convincingly:
a phentolamine infusion was started at 0.17 mg/min and titrated for BP control. Over 6 h, the FIO2 requirements dropped precipitously, gas exchange improved, and the chest radiograph showed improvement of pulmonary edema. When the hospital supply of phentolamine was exhausted, the clinical status deteriorated rapidly. Within just 15 h of the discontinuation of phentolamine, the PaO2 fell from 166 mm Hg to 66 mm Hg, and FIO2 requirements rose from 60% to 100%. When the phentolamine supply was replenished and the infusion restarted, the same rapid improvement was observed and BP stabilized.
Phentolamine is a potent competitive antagonist at both alpha 1 and alpha 2 receptors . Phentolamine causes a reduction in peripheral resistance through blockade of alpha 1 receptors and possibly alpha 2 receptors on vascular smooth muscle.
Neurogenic pulmonary edema (NPE) is a clinical syndrome characterized by the acute onset of pulmonary edema following a significant CNS insult. The cause is believed to be a surge of catecholamines that results in cardiopulmonary dysfunction. Although there are myriad case reports describing CNS events that are associated with this syndrome, few studies have identified specific treatment modalities. We present a case of NPE caused by an intracranial hemorrhage from a ruptured arteriovenous malformation. We uniquely document a rise and fall of serum catecholamine levels correlating with disease activity and a dramatic clinical response to IV phentolamine.
Neurogenic Pulmonary Edema: Successful Treatment With IV Phentolamine
Chest March 2012 vol. 141 no. 3 793-795
Comments Off on Clotbusting wisdom on tap – your questions answered
The prevention and management of venous thromboembolic disease is a huge topic, which generates questions for emergency, critical care, and acute physicians during many shifts:
- How long should someone requiring cardioversion for atrial fibrillation be anticoagulated for?
- How should I provide thromboprophylaxis for this intubated patient?
- This patient with submassive pulmonary embolism isn’t hypotensive yet. Can I thrombolyse them? Can I?
- There’s a large superficial vein thrombosis in that limb – is anticoagulation indicated?
- This asymptomatic patient on warfarin has an INR of 9.0 – should I reverse them?
- Do I need to add Vitamin K if I’ve reversed warfarin with prothrombin complex concentrate?
The answers to these – and many, many more – questions are provided in one of the most comprehensive guidelines I’ve ever come across. I can see myself clicking on the link below in future when on duty in the ED.
Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines
Chest. 2012 Feb;141(2 Suppl) Full Text
A systematic review and meta-analysis of randomised controlled trials showed dobutamine is not associated with improved mortality in heart failure patients and in the case of severe heart failure there is some suggestion of increased mortality, although this did not reach statistical significance.
The authors do point out that the quality of the reports of the trials reviewed was suboptimal. However, they state:
It should be noted that the results of this study are in accord with large observational studies that have also suggested harm associated with use of dobutamine in patients with severe heart failure. Taken together, this evidence should cause clinicians to reconsider their use of dobutamine in patients with heart failure, particularly those most at risk of the adverse effects, those with underlying ischaemic heart disease.
PURPOSE: Dobutamine is recommended for patients with severe heart failure; however uncertainty exists as to its effect on mortality. This study aims to critically review the literature to evaluate whether dobutamine, compared with placebo or standard care, is associated with lower mortality and a range of secondary outcomes, in patients with severe heart failure.
METHODS: A systematic review and meta-analysis of randomised controlled trials was performed. PubMed, EMBASE, the Cochrane Central Trials Registry, the metaRegister of Controlled Trials and bibliographies of retrieved articles were searched. Randomised trials comparing dobutamine with placebo or standard care, in human, adult patients with severe heart failure, were included if they reported at least one outcome of interest. Data regarding trial validity, methodological processes and clinical outcomes were extracted, and a meta-analysis was performed.
RESULTS: Fourteen studies, with 673 participants, met the inclusion criteria and were included; 13 studies reported mortality. There was minimal heterogeneity (I (2) = 4.5%). The estimate of the odds ratio for mortality for patients with severe heart failure treated with dobutamine compared with standard care or placebo was 1.47 (95% confidence interval 0.98-2.21, p = 0.06).
CONCLUSIONS: This meta-analysis showed that dobutamine is not associated with improved mortality in patients with heart failure, and there is a suggestion of increased mortality associated with its use, although this did not reach the conventional level of statistical significance. Further research to define the role of dobutamine in treatment of severe heart failure should be a priority.
Dobutamine for patients with severe heart failure- a systematic review and meta-analysis of randomised controlled trials
Intensive Care Med. 2012 Mar;38(3):359-67
The European Society of Intensive Care Medicine has produced a consensus statement on colloid volume therapy for critically ill patients, published in this month’s Intensive Care Medicine.
Curiously, the full text document is not yet availablle on ESICM’s website, but I found this presentation summarising the work by one the authors (Richard Beale):
PURPOSE: Colloids are administered to more patients than crystalloids, although recent evidence suggests that colloids may possibly be harmful in some patients. The European Society of Intensive Care Medicine therefore assembled a task force to compile consensus recommendations based on the current best evidence for the safety and efficacy of the currently most frequently used colloids-hydroxyethyl starches (HES), gelatins and human albumin.
METHODS: Meta-analyses, systematic reviews and clinical studies of colloid use were evaluated for the treatment of volume depletion in mixed intensive care unit (ICU), cardiac surgery, head injury, sepsis and organ donor patients. Clinical endpoints included mortality, kidney function and bleeding. The relevance of concentration and dosage was also assessed. Publications from 1960 until May 2011 were included. The quality of available evidence and strength of recommendations were based on the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach.
RECOMMENDATIONS AND CONCLUSIONS: We recommend not to use HES with molecular weight ≥200 kDa and/or degree of substitution >0.4 in patients with severe sepsis or risk of acute kidney injury and suggest not to use 6% HES 130/0.4 or gelatin in these populations. We recommend not to use colloids in patients with head injury and not to administer gelatins and HES in organ donors. We suggest not to use hyperoncotic solutions for fluid resuscitation. We conclude and recommend that any new colloid should be introduced into clinical practice only after its patient-important safety parameters are established.
Consensus statement of the ESICM task force on colloid volume therapy in critically ill patients
Intensive Care Med. 2012 Mar;38(3):368-83
Update September 2012:
An RCT showed patients with severe sepsis assigned to fluid resuscitation with HES 130/0.42 had an increased risk of death at day 90 and were more likely to require renal-replacement therapy, as compared with those receiving Ringer’s acetate. Read more about the trial here
Hydroxyethyl Starch 130/0.42 versus Ringer’s Acetate in Severe Sepsis
N Engl J Med. 2012 Jul 12;367(2):124-34
Australian intensivist John Myburgh gives a great summary of Fluid Therapy in critical care here
Comments Off on Body temperature in anaesthetised HEMS patients
This study raises an important issue – how do we keep patients with major trauma warm on the way to hospital? The authors from HEMS London identified mean temperatures in hospital of 35°C in patients who had been anaesthetised in the field, although only 38% of their patients had a temperature recorded on admission!
I emailed the author Audun Langhelle for practical information on the thermal protection package they use, who was most helpful in supplying the following information. Clicking on the link will take you to online supplements to the paper describing and illustrating their technique of prehospital rewarming.
Thank you for your request and interest in our paper. Now fully repatriated to Norway, we’re currently using the medium sized UniqueResc warming blanket (Geratherm, Germany) at my base, together with the bubble wrap. In Norway, Garatherm is the only company which has been able to provide us with the necessary paper work showing that their product complies with the rather strict pan European rules and regulations, the EN 13718-1: Requirements for medical devices used in air ambulances in particular.
Working as HEMS doc with LAA 2008-2009, we played with and introduced the policy using Diemme’s (Italy)DM EMG >> http://emj.bmj.com/content/early/2010/10/19/emj.2009.086967/suppl/DC1, but I’m not sure what blanket they currently use.
We reviewed this article in one of our Sydney HEMS Clinical Governance Days last year. One of our team presented a critical appraisal and if you’re interested the deadly PowerPoint slides are here:
Background Hypothermia at hospital admission has been found to independently predict increased mortality in trauma patients.
Objectives To establish if patients anaesthetised in the prehospital phase of care had a higher rate of hypothermia than non-anaesthetised patients on admission to hospital.
Methods Retrospective review of admission body temperature in 1292 consecutive prehospital trauma patients attended by a physician-led prehospital trauma service admitted to The Royal London Hospital between 1 July 2005 and 31 December 2008.
Results 38% had a temperature recorded on admission. There was a significant difference in body temperature between the anaesthetised group (N=207) and the non-anaesthetised group (N=287): mean (SD) 35.0 (2.1) vs 36.2 (1.0)°C, respectively (p <0.001). No significant seasonal body temperature variation was demonstrated.
Conclusion This study confirmed that patients anaesthetised in the prehospital phase of care had a significantly lower admission body temperature. This has led to a change in the author’s prehospital practice. Anaesthetised patients are now actively surface heated and have whole body insulation to prevent further heat loss in an attempt to conserve body temperature and improve outcome. This is an example of best in-hospital anaesthetic practice being carried out in the prehospital phase.