Article Notes
- Airway
- Cardiovascular & vascular
- General & physiology
- Head & neck
- Monitoring
- Obstetric
- Acute pain
- Chronic pain
- Pediatric anesthesia
- Preoperative management
- Postoperative care
- Pharmacology
- Regional & LA
- Pulmonary physiology
Fluid management and transfusion
It is ironic that as electronic access to medical literature becomes more pervasive, the ability for an individual to maintain a semblance of broad awareness of that body of knowledge becomes more difficult. (Tripathi, 2011)
This paper is full of many important pearls, and should be read in full.
Regarding common practices in the conduct of BIS-guided anaesthesia:
It has been suggested that a BIS range of 60–75 is suitable for ‘the end of surgery’, but our results show that if neuromuscular block is used, this range is consistent with full awareness.
...and on the use of the Signal Quality Index:
Given that the major cause of patient-related artifact is movement, it is not surprising that the SQI will increase towards 100 when NMBDs are administered, as we found. Unfortunately, the high SQI will indicate that the BIS is at its most reliable exactly when it is performing most poorly in the aware but paralysed patient.
Researchers induced awake paralysis in 10 volunteers using separately both suxamethonium and rocuronium. Both the BIS A2000 (2003) and BIS Vista monitor (2013) were tested.
BIS decreased immediately after paralysis and did not fully recover until muscle recovery. BIS values decreased to as low as 44, despite the subject being awake.
In more than half of the 20 trials the BIS value decreased to below 60 at some point. In one case this lasted for almost 4 minutes, representing 76% of the total paralysis time for that subject.
Interesting editorial accompanying Dr Peter Schuller's excellent study of BIS values in awake, paralysed volunteers.
The editors make a very interesting point critiquing the probabilistic, database-based approach to processed-EEG awareness monitors like BIS: (emphasis added)
"This database-driven approach may have limitations, in particular for the detection of intraoperative wakefulness: it is very unlikely that data from an awake and paralyzed subject are included in this database. Therefore, the resulting anaesthesia index has not been trained with a dataset that contains this clinical situation..."
A small audit showing the acceptability and absence of significant side effects of ketofol when used for brief procedural sedation (tubal ligation), particularly in the low resource setting.
Patients received a premixed ketofol dose of 0.5 mg/kg ketamine and 0.9 mg/kg propofol after fentanyl 1 mcg/kg.
Notably there was universal hemodynamic stability, although almost half of the audited patients required airway support.
The World Health Organisation's Surgical Safety Checklist has been adopted and implemented by many hospitals throughout the world: from large tertiary teaching hospitals in wealthy countries, to small hospitals in low-resource settings.
The benefits to each hospital however are likely not the same. Does the WHO SSC implemented in a hospital that already has a 'Time Out' process bring the same benefit, if any, as to a hospital for which the checklist was completely new? Possibly not.
Several studies across a wide range of health systems have shown conflicting results in terms of reducing morbidity, mortality and length of stay.
"It is ironic that as electronic access to medical literature becomes more pervasive, the ability for an individual to maintain a semblance of broad awareness of that body of knowledge becomes more difficult." (Tripathi, 2011)
A collection of the top 20 most cited pediatric anesthesiology papers of all time from Ravi Tripathi's excellent 2011 study:
Tripathi, R. A bibliometric search of citation classics in anesthesiology. BMC Anesthesiol. 2011 Jan 1;11:24.
These are probably 20 articles that every anaesthetist or anesthesiologist with even a small component of pediatric practice should be aware of – not necessarily because they are still practice changing, but because they our foundational to our current understanding and practice of pediatric anesthesia.
These articles help to both show where we have come from, and where we may be heading.
An excellent bibliographic study of the most cited anesthesia papers of all time, resulting in a collection of 600 papers across 15 subspecialty areas: