Featured Articles from November 2012

Intermediate Acting Non-Depolarizing Neuromuscular Blocking Agents and Risk of Postoperative Respiratory Complications: Prospective Propensity Score Matched Cohort Study

This is a prospective cohort study in 18,579 patients at one institution who had intermediate-acting neuromuscular blocking agents during surgery, and matched them with 18,579 surgical patients who didn’t have the drugs. The main outcomes were oxygen desaturation after extubation, and reintubation requiring unplanned admission to an ICU within 7 days of surgery.

Among patients who had at least one neuromuscular blockade, 0.8% were reintubated, 5% had a desaturation event below 90%, 1.1% had a desaturation event below 80%, and 0.3% died.

The use of the intermediate-acting neuromuscular agents was associated with a 36% higher risk of a postoperative oxygen desaturation event below 90% (OR 1.36, 95% CI 1.23 to 1.51, P<0.01), and a 66% higher risk of a desaturation event below 80% (OR 1.66, 95% CI 1.34 to 2.07, P<0.01). The drugs also appeared to raise the risk of reintubation requiring admission to the ICU (OR 1.40, 95% CI 1.09 to 1.80, P<0.01), a “serious complication” that also increased the risk of dying in the hospital.

Most of the reintubations occurred within the first 3 days after surgery, with a peak during the first 24 hours. Qualitative monitoring of neuromuscular transmission did not decrease this risk and neostigmine reversal increased the risk of postoperative desaturation less than 90% (1.32, 1.20 to 1.46) and reintubation (1.76, 1.38 to 2.26).

The authors concluded that the use of intermediate acting neuromuscular blocking agents during anesthesia was associated with an increased risk of clinically meaningful respiratory complications.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3473088

Management of Obstructive Sleep Apnea in Pregnant Women

Women with known OSA who become pregnant should be evaluated by their sleep medicine provider, particularly if the patient is untreated or has not been evaluated in the previous 6 months. Women who do not have a diagnosis of OSA but have symptoms of excessive sleepiness, witnessed apneas, unexplained hypoxemia, or who are suspected of having OSA should be referred to a sleep medicine specialist for evaluation. In the absence of pregnancy-specific data to direct treatment as well as the minimal risk associated with treatment, we suggest treatment for all women with mild, moderate, or severe OSA. The goal of treatment is to normalize the apnea–hypopnea index and control sleep apnea related symptoms. All perioperative hypoxemia should be evaluated assessing for potential etiologies including life-threatening conditions. Protocols that call for continuous monitoring in the immediate postpartum period should serve as a screening period. In the presence of respiratory events such as desaturations, witnessed apneas, or bradypnea, postoperative patients with OSA should continue to be monitored until the patient can maintain their baseline oxygen saturation while at rest and undisturbed. An analgesic strategy that minimizes the need for systemic opioids should be used.

http://www.ncbi.nlm.nih.gov/pubmed/22433352