A review of burn first aid treatments highlights the paucity of evidence on which to make firm recommendations. The authors recommend using cold running tap water (between 2 and 15 degrees C) and to avoid ice or alternative therapies. The optimum duration of first aid application and the delay after the injury for which first aid can still be effective are two areas of research which need further exploration.
A review of first aid treatments for burn injuries
Burns. 2009 Sep;35(6):768-75
Category Archives: Resus
Life-saving medicine
Mallampati unhelpful in ED patients
A prospective study of 366 patients requiring intubation in the ED revealed by logistic regression analysis that the only component of the ‘LEMON’ classification* to be independently associated with difficult intubation was a thyroid-hyoid distance of less than 2 finger breadths. They conclude that Mallampati classification is not a useful tool in predicting difficult intubation in the ED and that the LEMON acrostic can be modified to “LEON.”
Determination of difficult intubation in the ED
Am J Emerg Med. 2009 Oct;27(8):905-10
*Further definition of LEMON and information on difficult airways are available in these presentation slides by Rob Vissers FACEP
Cricoid pressure – ?not so useless after all
An interesting MRI-based study of adult volunteers takes a further look at whether cricoid pressure effectively occludes the digestive tract. The authors assert that the part of the digestive tract at the level of the cricoid is the distal hypopharynx, that it is fixed in relation to the airway (making the previously demonstrated lateral oesophageal displacement irrelevant), and that the lumen may be obliterated during Sellick’s manouevre.
Accompanying pro and con editorials reaffirm the need for further clinical evidence on the effectiveness of the technique.
Cricoid pressure results in compression of the postcricoid hypopharynx: the esophageal position is irrelevant
Anesth Analg. 2009 Nov;109(5):1546-5
Fluids for cooling post cardiac arrest
Large volume cold fluid resuscitation after return of spontaneous circulation can contribute to effective cooling but does it impair cardiac or respiratory function? A retrospective review of 52 resuscitated cardiac arrest patients suggests that the infusion of large volumes of cold fluid does not cause a further significant reduction in respiratory function beyond that normally seen after cardiac arrest despite significantly reduced LV function.
Effects of large volume, ice-cold intravenous fluid infusion on respiratory function in cardiac arrest survivors
Resuscitation. 2009 Nov;80(11):1223-8
In the same issue of Resuscitation, a prospective study of cardiac arrest survivors in positive fluid balance from cold fluid cooling showed frequent evidence of hypovolaemia as determined by serial ultrasound assessment.
An accompanying editorial suggests this may be due to the systemic inflammatory response syndrome that follows successful cardiac arrest resuscitation; large volumes are tolerated well and myocardial dysfunction should not lead to restriction of fluids after cardiac arrest.
Assessment of intravascular volume by transthoracic echocardiography during therapeutic hypothermia and rewarming in cardiac arrest survivors
Resuscitation. 2009 Nov;80(11):1234-9
Paediatric gastric tubes
A child with status epilepticus has been stabilised and intubated and is awaiting admission to the paediatric intensive care unit. You decide to insert a nasogastric tube. The nurse asks the following questions:
1. What size gastric tube would you like?
[EXPAND Answer]A general guide is twice the size of the uncuffed tracheal tube.
A four year old for example would usually need a tracheal tube size of 5.0mm internal diameter (age/4 +4), so would need a 10 Fr gastric tube.
[/EXPAND]
2. To what length are you intending to insert it?
[EXPAND Answer]A formula based on height of the child can be used, so get your tape measure or length chart out:
For neonates < 2 weeks and children >8 years 4 months a method called NEMU (nose-ear-midxiphoid-umbilicus measurement) may be used.
[/EXPAND]
3. How will you confirm placement?
[EXPAND Answer]It is very likely this child will get a post-intubation chest radiograph and the gastric tube tip can be visualised on that. However non-radiological tests should be used and pH testing of the aspirate is recommended, looking for pH<6
[/EXPAND]
Further details on these measurements including positive and negative likelihood ratios of pH testing can be found in the evidence-based guideline from Cincinnati Children’s Hospital
Life threatening post partum haemorrhage
A mother may experience life-threatening haemorrhage after delivery of her baby. What can the resuscitation doctor do?
Rosen’s Emergency Medicine describes four main differential diagnoses: uterine atony, genital tract trauma, retained placental tissue, and coagulopathies, or the “four Ts”: tone, trauma, tissue, and thrombin.
As well as resuscitation with fluid and blood products and urgent obstetric and anaesthetic referral, efforts should be made to restore uterine tone with manual and pharmacological means, and consider tamponade of the haemorrhage.
The MOET (Management of Obstetric Emergencies & Trauma) Course outlines the following interventions for major obstetric haemorrhage:
- Empty uterus: deliver fetus if undelivered / remove placenta or retained products (this may need to be done digitally according to Rosen)
- Oxytocin / ergometrine / prostaglandin
- Massage & bimanual compression of uterus
- Repair genital tract injury
- Uterine packing or Rusch balloon
- Compression of aorta
- Surgical or interventional radiological options: internal iliac or uterine artery ligation, hysterectomy, arterial embolisation
A review of the different balloon tamponade devices available describes the urological Rusch balloon, the dedicated Bakri balloon, a condom sutured to a Foley catheter, multiple Foley catheters, and the Sengstaken-Blakemore tube (SBT). In order for the SBT balloon to reach the uterine fundus, either the tip of the catheter can be cut and the gastric balloon inflated, or the SBT can be folded and the oesophageal balloon inflated. Normal saline is used to inflate the balloon until tamponade is achieved. If the cervix is dilated, vaginal packing may be necessary to prevent migration of the balloon out of the uterus..
The Royal College of Obstetricians and Gynaecologists published 2009 guidelines on PPH. The full text is available here. After commencing resuscitation, summoning help, considering the ‘four T’s’, and examining the patient they recommend:
- Bimanual uterine compression (rubbing up the fundus) to stimulate contractions.
- Ensure bladder is empty (Foley catheter, leave in place).
- Syntocinon 5 units by slow intravenous injection (may have repeat dose).
- Ergometrine 0.5 mg by slow intravenous or intramuscular injection (contraindicated in women with hypertension).
- Syntocinon infusion (40 units in 500 ml Hartmann’s solution at 125 ml/hour) unless fluid restriction is necessary.
- Carboprost 0.25 mg by intramuscular injection repeated at intervals of not less than 15 minutes to a maximum of 8 doses (contraindicated in women with asthma).
- Direct intramyometrial injection of carboprost 0.5 mg (contraindicated in women with asthma), with responsibility of the administering clinician as it is not recommended for intramyometrial use.
- Misoprostol 1000 micrograms rectally.
Balloon tamponade may then be attempted in cases of uterine atony pending surgical haemostasis if necessary.
As with all life-threatening emergencies, the resuscitation doctor should have a plan, and know his or her options regarding personnel, facilities and equipment. We recommend a closer look at the articles and guidelines referenced above in formulating your own plan as to how you might save a young mother’s life.
Spinal Cord Injury Guidelines
The Paralyzed Veterans of America produce a number of evidence-based guidelines for management of spinal cord injury and its complications that may be useful for the critical care doctor, downloadable from here.
The most relevant to frontline professionals is the Early Acute Management in Adults with Spinal Cord Injury: A Clinical Practice Guideline for Health-Care Professionals. A summary of the major recommendations from this document can be found here.
Which 'flu mask for staff?
A Canadian study in which 446 nurses were randomised to wear one or the other showed a standard surgical mask to be non-inferior to a N95 mask in preventing flu infection in the health workers.
Surgical Mask vs N95 Respirator for Preventing Influenza Among Health Care Workers
JAMA. 2009 Nov 4;302(17):1865-71
Vehicle Rollover
Vehicle rollover as an indicator of mechanism of injury was investigated in a study examining accident databases and the medical literature. Only 2.4% of crashes involved rollovers but they accounted for one third of occupant deaths.
Some facts on vehicle rollover from the article:
- Rollover is defined as a vehicle overturned by at least one quarter turn (at least onto its side).
- Some rollovers involve many quarter turns and the final resting position may be on the vehicle’s side, roof, or back on its wheels.
- Factors that cause a vehicle to roll over include trajectory (i.e., turning vs. straight), vehicle type, and speed (precrash velocity may be the most predictive factor)
The importance of vehicle rollover as a field triage criterion
J Trauma. 2009 Aug;67(2):350-7
Myocardial infarction not so common in LBBB?
An observational cohort study of 7937 ED visits by patients presenting with chest pain or ‘ischemic equivalent’ (shortness of breath for which ACS was considered a possible cause) was done to examine the relationship between left bundle branch block (LBBB) on the ECG and the incidence of acute myocardial infarction (AMI). No difference was observed in the rates of AMI in patients with new or presumed new LBBB, old LBBB, and no LBBB. The authors suggest that this large cohort of undifferentiated ED patients may be more reflective of the true prevalence of AMI in LBBB (7.3% in this study) and question the appropriateness of a liberal fibrinolytic strategy for such patients. Another argument for primary PCI?
Lack of association between left bundle-branch block and acute myocardial infarction in symptomatic ED patients
Am J Emerg Med. 2009 Oct;27(8):916-21