Article Notes
Is the effect exclusive to perineural dexamethasone? Several studies have observed similar effects for both IV and perineural dexamethasone (though less profound than other papers).
Is the effect safe? This is perhaps the most concerning, as there are suggestions that the effect may represent an enhancement of the well-known neurotoxicity of local anaesthetic agents.
- Recognition
- Calling for help
- A B C (D)
- Good for mother = good for baby
- Airway difficulties are more likely.
- Aortocaval compression dramatically impedes resuscitation – employ left lateral tilt!
- Consider perimortem cesarean section
- The presence of baby and gravid uterus severely limits resuscitation of the mother.
- Emergency cesarean section at cardiac arrest is done for the mother’s benefit, not the baby.
- A decision to perform emergency CS must be made within 4 minutes of arrest, and the baby delivered within 5 minutes. (Although there is some evidence of benefit when performed up to 10 minutes after arrest.)
- The only equipment required is a scalpel and an appropriately skilled doctor.
The potential for dexamethasone and other glucocorticoids to prolong peripheral nerve blocks was first noted almost 20 years ago.
While the effect has been observed with several different blocks (upper & lower extremity, and even TAP blocks), the clinical significance varies and several questions still remain:
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.
Miller enthusiastically states:
“Sugammadex is likely the most exciting drug in clinical neuromuscular pharmacology since the introduction of atracurium and vecuronium in the middle 1980s.”
...and hints at where benefits may begin:
“Will sugammadex’s increased effectiveness, in comparison to neostigmine, lessen the need for or use of monitoring neuromuscular function?”
An interesting CICO case study highlighting that while sugammadex will rapidly and completely reverse paralysis, this is only one consideration when managing an airway crisis. The use of any reversal agent in an airway crisis should be considered within the context of the case and a clear understanding of the objective of our actions.
Neuromuscular reversal will only improve a CICO scenario if spontaneous ventilation will improve patient oxygenation, otherwise return of muscle function may actually make other CICO interventions more difficult.
Hydroxyethyl starches, such as Hespan, Voluven, Volulyte, Tetrahes and Hestar, have been shown in several large trials to increase the risk of acute kidney injury (AKI) and/or the need for renal replacement therapies among critically ill patients, particulalry those suffering sepsis.
Evidence demonstrating harm among fit & healthy surgical patients is however lacking, notably Giles et al could find no increased risk of adverse event among surgical patients in their 2014 meta-analysis. Nonetheless, given the similar lack of demonstrable benefit of HES fluids for this group, avoidance of use in both the ICU and surgical population is prudent.
One of the early papers that lit the fire under the pro-periop beta-blocker camp. Note that the legitimacy of Poldermans' DECREASE trials has been called into question due to scientific misconduct (read more)
Results from more recent trials, such as POISE greatly undermine Poldermans' rather extraordinary findings in this paper.
"Extraordinary claims require extraordinary evidence" — Carl Sagan
Cardiac arrest is rare in pregnancy (1 in 30,000) and resuscitation is founded on the same approach used for the non-pregnant patient, focusing on:
However, unique to maternal resuscitation:
The rationale for Perimortem Cesarean Section is: