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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
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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
comment
1
Is the prolonged effect thought due to Dexmetetomidine's high protein binding?
Tong Y, Ren H, Ding X et al. Analgesic effect and adverse events of dexmedetomidine as additive for pediatric caudal anesthesia: a meta-analysis. Paediatr Anaesth. 2014 Dec 1;24(12):1224-30.
  Pieter Peach
summary
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An audit of 115 parturients requiring spinal anesthesia for cesarean section in the setting of an inadequate, pre-existing epidural block. Median dose of 9.38 mg of bupivacaine + 15 mcg fentanyl was used. No patients received an epidural bolus within 30 min of their subarachnoid block.
There were no cases of total spinal block.
Because total spinal after inadequate epidurals had been 'not uncommon' in the department, the researchers had altered the department's practice to be:
1. Ensuring at least 30 min since last epidural bolus.
2. Reducing spinal dose by 20%. (NB: plain bupivacaine used)
3. Delay supine positioning for 2 min after spinal performed.
(Plus patient weight < 120 kg and height > 1.47 m)
Dadarkar P, Philip J, Weidner C et al. Spinal anesthesia for cesarean section following inadequate labor epidural analgesia: a retrospective audit. Int J Obstet Anesth. 2004 Oct 1;13(4):239-43.
  Daniel Jolley
comment
0
Far from earth-shattering, though what I find (possibly) interesting is the long delay between the last epidural dose and the (apparent) total spinal.
90 min seems like it should be well and truly long enough for any epidural bupivacaine to be absorbed – in fact, this is probably only a little shorter than the duration of said dose. It's possible that the total spinal was totally unrelated to the epidural, but that's probably wishful thinking.
Previous studies (Dadarkar, IJOA 2014) have suggested that waiting 30 min between last epidural dose and spinal is safe (audit of 115 patients in Dallas).
The take-away for me is that there's probably more patient variability than we'd like to admit.
Siddik-Sayyid SM, Gellad PH, Aouad MT. Total spinal block after spinal anesthesia following ongoing epidural analgesia for cesarean delivery. J Anesth. 2012 Apr 1;26(2):312-3.
  Daniel Jolley
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A case study describing a total spinal occurring in a 26 year old having an emergency caesarean section for failure to progress.
On arrival in theatre a block to pin prick was noted to T12, with the last epidural top-up having been 90 minutes earlier with only 5 mL of 0.25% bupivacaine. Total volume of epidural LA is not reported.
The epidural had partially dislodged, so anaesthesia was with 10.5 mg of spinal bupivacaine (equivalent to 2.1mL of 0.5%) resulting in a block to T6. 10 minutes later the patient became distressed, followed by respiratory arrest and unconsciousness.
Baby was delivered uneventfully and the mother made a full recovery. The authors ascribed the case to a total spinal resulting from cephalad spread of intrathecal bupivacaine.
Siddik-Sayyid SM, Gellad PH, Aouad MT. Total spinal block after spinal anesthesia following ongoing epidural analgesia for cesarean delivery. J Anesth. 2012 Apr 1;26(2):312-3.
  Daniel Jolley
comment
1
Though I don't generally trust propensity matched based studies, this one does rather support my pre-existing bias! One can get by with a GA but regional makes life easier for all concerned!
Hausman MS, Jewell ES, Engoren M. Regional Versus General Anesthesia in Surgical Patients with Chronic Obstructive Pulmonary Disease: Does Avoiding General Anesthesia Reduce the Risk of Postoperative Complications? Anesth. Analg. 2015 Jun 1; 120 (6): 1405-12.
  Allan Palmer
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A clear and nuanced critique of the Northern Territory government's policy of removing speed limits on sections of the Stuart Highway. Read explores evidence linking driving speed and posted speed limits with vehicle accidents and trauma, noting that for the Territory:
• Northern Territorians are "... three times more likely to die on the roads than people living in other parts of Australia, and at a rate that is equivalent to that in many low- and middle-income countries."
• After the last open speed limits were abolished in 2007, the "Australian road deaths database shows a decrease in fatalities of 3.4 per year on those NT roads..."
He concludes that the NT needs a stronger road safety package that includes removing unlimited speed limits along with driver fatigue, alcohol and seatbelt interventions.
Read DJ. Open speeds on Northern Territory roads: not so fast. Med. J. Aust. 2015 Jul 6;203(1):14-5.
  Daniel Jolley
summary
1
This prospective observational study across eight Canadian hospitals identified post-operative residual paralysis in 64% of patients at extubation and 57% on arrival in the PACU, despite more than 70% of patients receiving reversal with neostigmine.
Rocuronium was the muscle relaxant used in 99% of cases.
Fortier LP, McKeen D, Turner K et al. The RECITE Study: A Canadian Prospective, Multicenter Study of the Incidence and Severity of Residual Neuromuscular Blockade. Anesth. Analg. 2015 Aug 1; 121 (2): 366-72.
  Daniel Jolley