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summary
1
The COMET trial was a landmark study demonstrating the benefit on mode of delivery of using either a low-concentration (0.1% bupivacaine + 2mcg/mL fentanyl) epidural infusion or a combined spinal-epidural technique, over a traditional high-dose (10mL boluses of 0.25% bupivacaine) epidural.
Vaginal delivery rate was significantly higher in the low-dose (OR 1.38) and CSE (OR 1.39) groups than in the traditional high-dose group.
Comparative Obstetric Mobile Epidural Trial (COMET) Study Group UK. Effect of low-dose mobile versus traditional epidural techniques on mode of delivery: a randomised controlled trial. Lancet. 2001 Jul 7;358(9275):19-23.
  Daniel Jolley
pearl
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Low-concentration bupivacaine epidurals for labor analgesia result in a lower-incidence of instrumental delivery than 'traditional' high-dose bupivacaine epidurals.
Comparative Obstetric Mobile Epidural Trial (COMET) Study Group UK. Effect of low-dose mobile versus traditional epidural techniques on mode of delivery: a randomised controlled trial. Lancet. 2001 Jul 7;358(9275):19-23.
  Daniel Jolley
summary
1
Collection: Landmark obstetric anesthesia papers
A collection of landmark research articles relevant to obstetric anesthesia. Some, such as Hawkins' audits of U.S. maternal deaths, are significant because of their historical impact. Others hold direct clinical relevance for practice today.
  Daniel Jolley
summary
1
This follow-up paper to Hawkin's original "Anesthesia-related deaths during obstetric delivery in the United States, 1979-1990" showed a dramatic improvement in the relative risk of cesarean section death with general vs regional anesthesia compared with the original 1979-1990.
Where previously (1979-1990) the relative risk of death during GA CS was 16.7, from 1997-2002 the relative risk had fallen to 1.7. Worryingly though this was both due to a falling mortality rate for GA CS and an increasing mortality rate for regional anesthesia CS.
Cesarean section under general anesthesia still exposes mothers to an increased risk of perioperative death, but this risk is much lower than previously, likely due to better anesthesia training, supervision and respect of the obstetric airway.
Hawkins JL, Chang J, Palmer SK et al. Anesthesia-related maternal mortality in the United States: 1979-2002. Obstet Gynecol. 2011 Jan 1;117(1):69-74.
  Daniel Jolley
summary
1
This historical landmark paper demonstrated the terribly-higher maternal mortality during cesarean section performed under general anesthesia vs regional anesthesia in the United States from 1979-1990.
This resulted in the oft-quoted statistic of being '...17 times more likely to die under a GA cesarean section than epidural or spinal.'
It is very important to note that this is a historical article and that the demonstrated very high mortality was greatly contributed to by a culture tolerating inexperienced anesthesia residents performing GA CS after-hours with limited senior support.
Hawkins followed up this study with another in 2011: Anesthesia-related maternal mortality in the United States: 1979-2002. This reassuringly showed a much improved GA CS maternal mortality from 1997-2002 (although still higher than regional CS).
The important take-home from this paper is that a GA cesarean section increases the risk of serious airway events, and if this is not managed by experienced and appropriately trained anaesthetists/anesthesiologists, will result in maternal deaths.
Hawkins JL, Koonin LM, Palmer SK et al. Anesthesia-related deaths during obstetric delivery in the United States, 1979-1990. Anesthesiology. 1997 Feb 1;86(2):277-84.
  Daniel Jolley
pearl
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Upper airway complications are no different with desflurane than for sevoflurane, isoflurane or propofol anesthesia when using an LMA.
Stevanovic A, Rossaint R, Fritz HG et al. Airway reactions and emergence times in general laryngeal mask airway anaesthesia: A meta-analysis. Eur J Anaesthesiol. 2015 Feb 1; 32 (2): 106-16.
  Daniel Jolley
pearl
1
In patients with atrial fibrillation requiring cessation of warfarin for surgery, bridging anticoagulation does not change the incidence of thromboembolism, although does increase major bleeding.
Douketis JD, Spyropoulos AC, Kaatz S et al. Perioperative Bridging Anticoagulation in Patients with Atrial Fibrillation. N. Engl. J. Med. 2015 Aug 27;373(9):823-33.
  Daniel Jolley
summary
1
This review of five trials investigating the efficacy of mechanical CPR devices (the LUCAS & AutoPulse) concluded that the devices demonstrate no outcome advantage compared with manual CPR, in terms of 30 day survival, survival to discharge, or neurological outcome.
Gates S, Quinn T, Deakin CD et al. Mechanical chest compression for out of hospital cardiac arrest: Systematic review and meta-analysis. Resuscitation. 2015 Sep 1; 94: 91-7.
  Daniel Jolley
summary
2
This controlled study randomised 212 children to either deep plane-of-anesthesia or awake, and either supine or lateral position, for removal of their laryngeal mask at the completion of surgery.
"Deep anesthesia" was defined as ET-sevoflurane 2.2%, stable for 1 minute. The "awake" group had their LMA removed by the PACU nurse after eye opening and/or obeying commands.
Airway complications included desaturation < 90%, stridor, laryngospasm, retching/vomiting, excess secretions and biting. A secondary outcome was also studied, assigning a 'clinical significance score' to the range of complications.
Deep removal in the lateral position was associated with the fewest complications. Deep removal when supine was associated with the most complications.
This study was a follow-up to a two-centre observational audit from 2008.
Thomas-Kattappurathu G, Kasisomayajula A, Short J. Best position and depth of anaesthesia for laryngeal mask airway removal in children: A prospective randomised controlled trial. Eur J Anaesthesiol. 2015 Sep 1; 32 (9): 624-30.
  Daniel Jolley
pearl
2
The fewest airway complications occur when a pediatric LMA is removed deep and in the lateral position.
Thomas-Kattappurathu G, Kasisomayajula A, Short J. Best position and depth of anaesthesia for laryngeal mask airway removal in children: A prospective randomised controlled trial. Eur J Anaesthesiol. 2015 Sep 1; 32 (9): 624-30.
  Daniel Jolley