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pearl
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Restrictive fluid management intraoperatively in liver transplantation does not appear to reduce kidney injury or mortality, but may modestly reduce pulmonary complications and duration of mechanical ventilation.
Carrier FM, Chassé M, Wang HT et al. Restrictive fluid management strategies and outcomes in liver transplantation: a systematic review. Can J Anaesth. 2020 Jan 1; 67 (1): 109-127.
  Daniel Jolley
pearl
1
Although suprascapular nerve block reduces nausea & vomiting and improves patient satisfaction after shoulder surgery when compared to morphine alone, it results only in clinically insignificant objective improvement of analgesia.
Cho N, Kang RS, McCartney C J L CJL Department of Anesthesiology Pain Medicine, University of Ottowa, ON, Canada. et al. Analgesic benefits and clinical role of the posterior suprascapular nerve block in shoulder surgery: a systematic review, meta-analysis and trial sequential analysis. Anaesthesia. 2020 Mar 1; 75 (3): 386-394.
  Daniel Jolley
pearl
1
Although there is some evidence that ketamine may reduce emergence delirium in children, it is generally low quality and inconsistent, and practice change is not recommended.
Ng KT, Sarode D, Lai YS et al. The Effect of Ketamine on Emergence Agitation in Children: A Systematic Review and Meta-analysis. Paediatr Anaesth. 2019 Dec 1; 29 (12): 1163-1172.
  Daniel Jolley
pearl
0
Bacteriophage therapy may offer one answer to growing bacterial antibiotic-resistance.
Petrovic A, Khalid A, Maddocks S et al. Phage therapy for severe bacterial infections: a narrative review. Med. J. Aust. 2020 Apr 1; 212 (6): 279285279-285.
  Daniel Jolley
pearl
1
Hypertonic saline use in sepsis reduces resuscitation fluid volume but has no effect on survival.
Orbegozo D, Vincent JL, Creteur J et al. Hypertonic Saline in Human Sepsis: A Systematic Review of Randomized Controlled Trials. Anesth. Analg. 2019 Jun 1; 128 (6): 117511841175-1184.
  Daniel Jolley
pearl
1
Intensivists hold different views on their own thresholds for intensive care admission versus those they hold for patients.
Fumis Renata Rego Lins RRL Dept. of Critical Care Medicine, Hospital Sírio-Libanês, São Paulo, Brazil. Electronic address: renata.rlfumis@hsl.org.br., GPP Schettino, Rogovschi PB et al. Would you like to be admitted to the ICU? The preferences of intensivists and general public according to different outcomes. J Crit Care. 2019 Oct 1; 53: 193-197.
  Daniel Jolley
pearl
1
There is inadequate evidence supporting the benefit of music on sedation, analgesia or delirium in critically ill patients.
Garcia Guerra Gonzalo G Department of Pediatrics, University of Alberta, Edmonton, AB, Canada; Stollery Children's Hospital, Edmonton, AB, Canada., Almeida L, Zorzela L et al. Efficacy of music on sedation, analgesia and delirium in critically ill patients. A systematic review of randomized controlled trials. J Crit Care. 2019 Oct 1; 53: 75-80.
  Daniel Jolley
pearl
1
Subcostal transversus abdominis plane (TAP) block does not improve analgesia after laparoscopic cholecystectomy.
Houben AM, Moreau AJ, Detry OM et al. Bilateral subcostal transversus abdominis plane block does not improve the postoperative analgesia provided by multimodal analgesia after laparoscopic cholecystectomy: A randomised placebo-controlled trial. Eur J Anaesthesiol. 2019 Oct 1; 36 (10): 772-777.
  Daniel Jolley
pearl
1
Anesthesiologists are overconfident in their knowledge and management of neuromuscular blocking drugs.
Naguib M, Brull SJ, Hunter JM et al. Anesthesiologists' Overconfidence in Their Perceived Knowledge of Neuromuscular Monitoring and Its Relevance to All Aspects of Medical Practice: An International Survey. Anesth. Analg. 2019 Jun 1; 128 (6): 111811261118-1126.
  Daniel Jolley
summary
1
What’s so interesting?
De Carvalho and co. show that pre-operative voice analysis can be predictive of difficult laryngoscopy.
I’d never thought about that...
The authors describe how different frequency components and acoustic qualities of the voice are, at least partly, determined by the shape and size of different anatomical areas of the vocal tract. By analysing the most intense frequencies (voice formants) within the voice spectrum they were able to correlate components with difficult laryngoscopy, namely Cormack & Lehane grade 3 or 4.
The practicalities
During pre-anaesthetic assessment, 467 elective general surgical patients were asked to pronounce each of the five vowels, corresponding to base phonemes. This was recorded on a smartphone and then later processed and analysed on a laptop computer.¹
They found...
A model using voice ‘formants’ could reliably predict difficult laryngoscopy with a ROC-AUC of 0.761 (ie. 76% probability that it correctly classifies a patient as difficult or not). When combined with the modified Mallampati this improved to 92%.
The big picture
While interesting, it’s worth remembering that using voice formants (76%) did not perform as well as modified Mallampati alone (87%), and that this performance is also surprisingly much better than those from the most recent Cochrane meta-analysis (2018) of bedside airway assessment. Over 133 studies the Cochrane review reported a summary sensitivity of only 53% and specificity of 80% for the modified Mallampati (vs 100% and 75% respectively for this study).
Although this is an interesting and novel new test, it’s just not that simple... Screening for an uncommon outcome using tests with imperfect sensitivity and specificity is already problematic, but doubly so when we are not always certain which outcome we should be screening for (laryngoscopy, intubation, ventilation, oxygenation...).
As an airway screening test, voice analysis is both different and also more of the same.
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1. It would also be feasible for recording, analysis and reporting to occur entirely at the bedside on a smartphone. ↩
de CC, da DM, de AD et al. Pre-operative voice evaluation as a hypothetical predictor of difficult laryngoscopy. Anaesthesia. 2019 Sep 1; 74 (9): 1147-1152.
  Daniel Jolley