Simple really. Using the transverse view the needle tip can be hard to visualise. In the longitudinal view you don’t see the carotid artery. Applying an oblique view with an obliquely oriented needle “uses the superiority of the short axis view by visualizing all of the important surrounding structures (artery and vein) in an oblong view while allowing continuous real-time visualization of the long axis of the needle, therefore providing a larger, more easily visible target with a brighter more easily recognized needle.” The ultrasound probe is orientated at approximately 45° so that the medial end of the ultrasound probe aligns with the patient’s contralateral nipple or shoulder.
The oblique view: an alternative approach for ultrasound-guided central line placement
J Emerg Med. 2009 Nov;37(4):403-8
Full Text Article
Monthly Archives: March 2010
10 ml syringe for Valsalva manoeuvre
Previous studies have suggested the following are necessary for a successful Valsalva manoeuvre with maximum vagal effect:
- Supine posturing
- Duration of 15 seconds
- Pressure of 40 mmHg (with an open glottis)
One popular method of generating a Valsalva Manoeuvre is to get the patient to blow into a syringe in an attempt to move the plunger. Different syringe sizes were tested. A 10ml (Terumo) syringe was best
The 10 mL syringe is useful in generating the recommended standard of 40 mmHg intrathoracic pressure for the Valsalva manoeuvre
Emerg Med Australas. 2009 Dec;21(6):449-54
Stopping infusions before PCI transfer
An interhospital transport service introduced a no infusions policy for patients being transferred for primary coronary intervention, instead giving a bolus of heparin and glycoprotein 2b-3a inhibitor prior to transfer, along with non-intravenous nitrates (if needed). Discontinuing infusions during transport resulted in a significant reduction in transport times with no adverse effect on hospital length of stay or mortality. It did not significantly extend the time the patient spent in the catheterisation laboratory, nor did it impact the incidence of TIMI III flow. It did not impact the incidence of readmission to the hospital for cardiac-related chief complaints.
Transporting without infusions: effect on door-to-needle time for acute coronary syndrome patients
Prehosp Emerg Care. 2010 Apr 6;14(2):159-63
Better TBI outcome with HEMS
A retrospective study from Italy compared outcomes of head injured patients cared for by a ground ambulance service (GROUND) with those managed by a HEMS team that included an experienced pre-hospital anaesthetist. Interestingly 73% of the ground group were also attended by a physician, but one ‘with only basic life-support capabilities and no formal training in airways management’. Despite these limited skills a results table shows that 36% of the GROUND group were intubated on scene (compared with 92% of the HEMS group), although without the use of neuromuscular blockers.
The HEMS group consisted of 89 patients and the GROUND group of 105 patients. There were no statistical differences in age, ISS, aISShead, or GCS, although arterial hypotension at arrival at the ER was present in 18% of HEMS patients and in 36% of GROUND patients (P < 0.001).
The overall mortality rate was lower in the HEMS than in the GROUND group (21 vs. 25% , P < 0.05). The survival with or without only minor neurological disabilities was higher in the HEMS than in the GROUND group (54 vs. 44% respectively, P < 0.05); among the survivors, the rate of severe neurological disabilities was lower in the HEMS than in the GROUND group (25 vs. 31%, P < 0.05). The out-of-hospital phase duration was longer in the HEMS group but this group had a faster time to definitive care (neurosurgery or neurocritical care).
Influence of prehospital treatment on the outcome of patients with severe blunt traumatic brain injury: a single-centre study
Eur J Emerg Med. 2009 Dec;16(6):312-7
5 Cycles of CPR takes 2 minutes
Newly trained BLS providers were more likely to spend two minutes counting 5 cycles of 30:2 compression:ventilation than to correctly identify when two minutes had elapsed.
Using the 30 : 2 compression–ventilation ratio: five cycles is easier to follow than 2 min of cardiopulmonary resuscitation
Eur J Emerg Med. 2009 Dec;16(6):339-41
Abnormal head CT in altered mental status
In a study of 674 patients with altered mental status who received a CT scan of the brain, logistic regression analysis identified a series of clinical factors that were associated with an abnormal CT result.
Factors with an adjusted odds ratio between 1 and 2.5 included GCS less than 15, focal weakness, diastolic blood pressure greater than 80mmHg and antiplatelet use.
Four variables were associated with an adjusted odds ratio of 2.5 or above. These included presence of headache, dilated pupils (either unilateral or bilateral), upgoing plantar response and anticoagulant use.
Identifying risk factors for an abnormal computed tomographic scan of the head among patients with altered mental status in the Emergency Department
Eur J Emerg Med. 2009 Sep 21. [Epub ahead of print]
EGDT sepsis bundle challenged
An article in American Journal of Emergency Medicine by two intensivists challenges the science behind Rivers’ early goal-directed therapy (EGDT) protocol for severe sepsis / septic shock. In a nutshell:
- Rivers’ study was small (n = 263), nonblinded, industry-supported and single-center
- early fluids and antibiotics are a sound idea, but other components of EGDT are flawed
- targeting a CVP is meaningless and could result in hypovolaemia or pulmonary oedema; dynamic markers of preload responsiveness such as pulse pressure variation or IVC diameter variation are better guides to fluid resuscitation
- ScvO2 may be normal or elevated in septic shock patients; the low average ScvO2 in Rivers’ study has not been reproduced in subsequent studies.
- packed cells have significant side effects and their non-deformability, pro-inflammatory and pro-thrombotic effects may impair microvascular perfusion and paradoxically worsen tissue oxygen delivery
- dobutamine can potentially further worsen the haemodynamic status of patients with hypovolaemia, vasodilation, or a hyperdynamic circulation, which cannot be differentiated using CVP and ScvO2
Early goal-directed therapy: on terminal life support?
Am J Emerg Med. 2010 Feb;28(2):243-5
I like this paper, mainly because I have been uncomfortable with the chasing of arbitrary targets for some time. My own practice is to try to improve markers of organ hypoperfusion (such as lactate, urine output, mental status, and skin perfusion as well as blood pressure) by early antibiotics, fluid resuscitation guided by clinical and sonographic (IVC) signs, and vasoactive drugs guided by clinical and sonographic (basic echo) findings. I place a central venous catheter for access for the vasoactive drugs, rather than to get a CVP reading. I do measure ScvO2 with a central venous blood gas, but have rarely seen one below 70% even in severely shocked patients – I’m far more interested in clearing the lactate, as are these guys.
Biphasic shocks for AF and Atrial flutter
Based on a study of 453 consecutive patients undergoing their first transthoracic electrical cardioversion for atrial tachyarrhythmias, recommendations were developed to aim at delivering the lowest possible total cumulative energy with ≤2 consecutive shocks using the specific truncated exponential biphasic waveform incorporated in Medtronic Physio-Control devices: they recommend an initial energy setting of 50 J in patients with atrial flutter or atrial tachycardia, of 100 J in patients with atrial fibrillation (AF) of 2 or less days in duration, and of 150 J with AF of more than 2 days in duration. If the initial shock fails to restore sinus rhythm, a rescue shock of 250 J for AFL/AT or of 360 J for AF should be applied to secure the highest possible probability of successful cardioversion for each patient.
Optimization of initial energy for cardioversion of atrial tachyarrhythmias with biphasic shocks
Am J Emerg Med. 2010 Feb;28(2):159-65
Preventing AKI on the ICU
A multinational European working group produced the following evidence-based recommendations for preventing acute kidney injury (AKI). Read the full guideline before criticising – some are just suggestions, some recommendations; I have not included the strength of recommendation or grade of evidence in my summary below.
Volume expansion
Diuretics
- Do not use loop diuretics to prevent or ameliorate AKI
Vasopressors and inotropes
- Maintain mean arterial pressure (MAP) at least 60–65 mmHg, however, target pressure should be individualized where possible, especially if knowledge of the premorbid blood pressure is available.
- In case of vasoplegic hypotension as a result of sepsis or SIRS use either norepinephrine or dopamine (along with fluid resuscitation) as the first-choice vasopressor agent to correct hypotension.
- Do not use low-dose dopamine for protection against AKI.
Vasodilators
- Use vasodilators for renal protection when volume status is corrected and the patient is closely hemodynamically monitored with particular regard to the development of hypotension.
- Prophylactic use of fenoldopam, if available, in cardiovascular surgery patients at risk of AKI. Do not use fenoldopam for prophylaxis of contrast nephropathy.
- Use theophylline to minimize risk of contrast nephropathy, especially in acute interventions when hydration is not feasible.
- Do not use natriuretic peptides as protective agents against AKI in critically ill patients, while its use may be considered during cardiovascular surgery.
Hormonal manipulation and activated protein C
- Avoid routine use of tight glycemic control in the general ICU population. Use “Normal for age’’ glycemic control with intravenous (IV) insulin therapy to prevent AKI in surgical ICU patients, on condition that it can be done adequately and safely applying a local protocol which has proven efficacy in minimizing rate of hypoglycemia.
- Do not use thyroxine, erythropoietin, activated protein C or steroids routinely to prevent AKI.
Metabolic interventions
- All patients at risk of AKI should have adequate nutritional support, preferably through the enteral route
- Do not use N-acetylcysteine as prophylaxis against contrast induced nephropathy or other forms AKI in critically ill patients because of conflicting results, possible adverse reactions, and better alternatives.
- Do not routinely use selenium to protect against renal injury.
Extracorporeal therapies
- Use periprocedural continuous veno-venous hemofiltration (CVVH) in an ICU environment to limit contrast nephropathy after coronary interventions in high-risk patients with advanced chronic renal insufficiency
Prevention of acute kidney injury and protection of renal function in the intensive care unit
Expert opinion of the working group for nephrology, ESICM
Intensive Care Med. 2010 Mar;36(3):392-411
Bad news for etomidate from CORTICUS
In an a priori substudy of the CORTICUS multi-centre, randomised, double-blind, placebo-controlled trial of hydrocortisone in septic shock, the use and timing of etomidate administration was examined in relation to outcome.
Of 499 analysable patients, 96 (19.2%) received etomidate within the 72 h prior to inclusion. The proportion of non-responders to ACTH was significantly higher in patients who were given etomidate than in other patients (61.0 vs. 44.6%, P = 0.004). Etomidate therapy was associated with a higher 28-day mortality in univariate analysis (P = 0.02) and after correction for severity of illness (42.7 vs. 30.5%; P=0.06 and P=0.03) in two multi-variant models. Hydrocortisone administration did not change the mortality of patients receiving etomidate (45 vs. 40%).
Some of the previous attacks on etomidate have not been founded on the most rigorous evidence. However this study adds further to the difficulty in justifying etomidate’s use when a perfectly acceptable alternative (ketamine) exists for rapid sequence induction in the haemodynamically unstable septic patient.
The effects of etomidate on adrenal responsiveness and mortality in patients with septic shock.
Intensive Care Med. 2009 Nov;35(11):1868-76