Saturday 24 August 2019

Decreased facial expression variability in patients with serious cardiopulmonary disease in the emergency care setting

Could “normal affect variation” be a new physical examination finding that predicts severity of illness?

Dr Jeff Kline thinks it might be. He’s the preeminent PE researcher who brought us the PERC rule. He has conducted this pilot study that suggests we might be on to something.

This was a prospective study of a convenience sample of patients presenting to the ED with dyspnea and chest pain. 50 patients looked at 3 stimulus slides on a laptop computer that recorded their facial expressions. Did their faces move when viewing the slides?

Two independent blinded observers reviewed the recordings and scored the change in facial expression using a coding system. The main analysis compared the results of the score to the patient’s presence of disease (predefined yes/no serious cardiopulmonary disease.)

How well did the change in facial expression perform?

It seemed to be ok.

The expression of surprise had the largest difference between yes/no disease with an area under the receiver operating curve (AUC) of 0.75. But given the low numbers, the confidence intervals were rather wide (95% CI 0.52 to 0.87).

Perhaps the biggest limitation to the study beyond the small numbers was the gold standard. How do we quantify “how sick” someone is? The authors acknowledge several patients did not meet their predefined determination of “serious cardiopulmonary disease” but were likely sick due to other pathology.

To be fair, Dr Kline points out that we consciously or unconsciously use affect variation as part of our gestalt assessment anyway. How many times have you heard an experienced clinician say, “the patient just looks sick…” But this study is a step towards standardisation and/or quantification of this implicit process.

Could artificial intelligence be the next step… perhaps. Dr Kline co-founded the company BreathQuant Medical Systems Inc that has many patents for medical devices. Perhaps we’ll have “affect variationometer” soon.


Kline JA, Neumann D, Huang MA, et al. Decreased facial expression variability in patients with serious cardiopulmonary disease in the emergency care setting. Emerg Med J 2015;32:3-8. [link to article]

Femoral Nerve Catheters Improve Home Disposition and Pain in Hip Fractures... maybe

There has been a push to perform nerve blocks for femoral neck fractures. Typically, these are single injections with a long acting anaesthetic. But continuous infusions through a femoral nerve catheter may supply better and longer lasting analgesia. Perhaps this could decrease complications from parenteral medications, allow for earlier mobilisation and get patients home faster?

This group from Stanford retrospectively reviewed health records of all geriatric hip fractures during a 4-hour period. About halfway through this time, this hospital started a hip fracture protocol that involved insertion of an ultrasound guided indwelling continuous female nerve catheter (CFNC).

They compared the before group that got standard analgesia vs. the CFNC. They sought to answer three questions; do CFNC improve home disposition rates, do they decrease pain scores & narcotic consumption, and does it decrease opioid-related side effects.  


43% of the patients getting CFNC were discharged home compared to 7% of the standard group. In addition, the patients with nerve catheters had lower pain scores, less opioids, and less side effects.

Sounds great!

But unfortunately, there are some big limitations.

They only included 29 patients. (I find it hard to believe that this was “all” patients with fractures at Stanford over 4 years… selection bias?) So, 43% vs. 7% is really 6 vs. 1 patient. This is hardly strong evidence.

Chart reviews are always problematic, and it does not look like this one followed the usually recommended methods. Of course, patients were not randomised. As such, there may have been some further selection bias.

I also wonder if the new protocol introduced other aspects of care that led to improvements. Perhaps this is why the “after” group looked better.

Nevertheless, I think the idea of femoral nerve catheters is quite compelling. Hopefully we can get further data to inform our practice.  


Arsoy D, Huddleston JI, Amanatullah DF, et al. Femoral Nerve Catheters Improve Home Disposition and Pain in Hip Fractures Treated with Total Hip Arthroplasty. J Arthro 2017;32:3434-3437. [link to full text]

Friday 23 August 2019

Behavioral Changes in Children After ED Procedural Sedation

Image result for dumb and dumber
It is unusual to see such an awful paper published in a reasonably respected journal. This addition to the medical literature has only made us dumber.

The purpose of this study was to determine the proportion of children undergoing procedural sedation for fracture reduction in the ED that have negative behaviours afterwards. With this information, the authors claim that we could possibly improve things by treating the child’s anxiety prior to sedation. (But this aspect was not studied).

This was a prospective cohort study of a convenience sample of kids getting IV ketamine for reduction of (mostly) broken arms. The child’s anxiety was measured on a scale prior to the procedure. Negative behaviours were measured by parents on another scale 1-2 weeks after discharge. There was no control or comparator group.

82 patients were analysed. 33 kids were “highly anxious” before sedation and 18 had negative behaviours after ED discharge.

The authors clearly imply that the procedural sedation itself was causal to the negative behaviours.


What about the traumatic event that caused the fracture, the pain from the injury, the wait to be seen by a doctor in a chaotic ED, the visible worry of the parents, the disruption to sleep, play, and activity from injury & plaster. Could they have potentially caused some anxiety afterward?

Evidently not… it must have been the ketamine from the procedural sedation.

This paper is shameful.

It is VERY likely the ketamine was protective of negative behaviours and changing this would have resulted in worse outcomes. When used correctly, ketamine is a wonderful drug for procedural sedation. It is incredibly safe, provides pain relief, amnesia and excellent conditions for procedures.


Pearce Ji, Brousseau DC, Yan K, et al. Behavioral Changes in Children After Emergency Department Procedural Sedation. Acad Emerg Med 2019;25:267-274. [link to article]

C-MAC vs Direct Laryngoscopy for Rapid Sequence Intubation in the ED

Prior studies have clearly proven a video laryngoscopes (VL) generally provide a better view of the chords. But does this translate into improved first pass success rates of intubation?

This study tried to determine which is ultimately better; a C-MAC or old fashion direct laryngoscopy (DL)? This is probably a decent research question.

150 ED patients undergoing RSI in a single ED in Zurich were randomised to either C-MAC vs. DL.  

For "ethical reasons" they excluded patients that they thought would be difficult to intubate. The primary outcome measure was first pass success rate. It was powered to find a 14% difference between the groups.

Unfortunately, all intubations were performed by one of three “very experienced” anaesthetic consultants.

Can you guess the first pass success rate for “very experienced” anaesthetists for simple intubations?

Yes, you guessed it… 100% in both groups. (Well, just about.)

This study was never going to find a difference and I wonder why they went to so much effort in the first place. Seems like it was always going to be a waste of time.

We already know that video laryngoscopes are taking over. But what do you do when the scope fails, unavailable, or needs rescue?

Learn both.


Sulser S, Ubmann D, Schlaepfer, et al. C-MAC videolaryngoscope compared with direct laryngoscopy for rapid sequence intubation in an emergency department. Eur J Anaesthesiol 2016;33:1-6. [link to article]