Literature Updates from May 2012

Impact of Smoking on Perioperative Pulmonary and Upper Respiratory Complications After Laparoscopic Gynecologic Surgery

The authors retrospectively identified all patients who underwent laparoscopic gynecologic surgery at one institution for 9 years and analyzed them by smoking status. The rate of pulmonary complications was 2.1% (12 of 564 patients) in never smokers, 4.5% (7 of 156 patients) in past smokers, and zero in current smokers.”

Health Effects of Identifying Patients with Undiagnosed Obstructive Sleep Apnea in the Preoperative Clinic: A Follow-up Study

The preoperative patients who were identified to have OSA and were compliant with CPAP use may have health benefits in terms of improved snoring, sleep quality, and daytime sleepiness. The CPAP compliant patients had a greater reduction in medication for comorbidities than the CPAP non-compliant or other treatment group. Timely diagnosis and treatment compliance may reduce symptoms of OSA and severity of associated comorbidities along with a reduction in medications.

Assessing REM Sleep in Mice Using Video Data

Due to technical challenges, monitoring sleep in animal models is always a difficult task. These authors presented a promising alternative high-throughput strategy using video analysis. This technique could obviate the need for EEG/EMG recording in distinguishing NREM from REM sleep.

Evidence for Neuronal Desynchrony in the Aged Suprachiasmatic Nucleus Clock

Aging leads to a deterioration of circadian rhythms in physiology and behavior. These authors analyzed circadian rhythms in the course of aging on different levels of organization. They were able to show that aging affects the suprachiasmatic nucleus at the network level organization as opposed to the single cell membrane deterioration “theory”.

Glucoregulatory Consequences and Cardiorespiratory Parameters in Rats Exposed to Chronic-Intermittent Hypoxia: Effects of the Duration of Exposure and Losartan

Treatment with CPAP may ameliorate pre-diabetic conditions in OSA patients, in part, by reducing sympathoexcitatory effects of recurrent nocturnal hypoxia.

The Childhood Adenotonsillectomy Trial (CHAT): Rationale, Design, and Challenges of a Randomized Controlled Trial Evaluating a Standard Surgical Procedure in a Pediatric Population

This paper addresses key elements in the design and implementation of a controlled trial for a widely used “standard practice” surgical intervention in a pediatric population, that include establishment of standardized data collection procedures across sites for a wide variety of data types, establishment of equipoise, and approaches for minimizing unblinding of selected key personnel.

Ambulatory Anesthesia Aspects for Tonsillectomy and Abrasion in Children

Preoperative evaluation should identify increased bleeding risk, potential airway problems, ongoing infection and symptoms of OSA. IV propofol is most often used for anesthetic induction, although inhalational sevoflurane is a valid alternative. LMA or endotracheal tube may both be used safely and effectively; the choice will depend upon the routine and experience of the team. Paracetamol and NSAIDs are useful baseline medication for nonopioid multimodal postoperative pain treatment and prophylaxis. Similar with local anesthesia infiltration and dexamethasone medication, although somewhat more disputed.

Supraglottoplasty for Occult Laryngomalacia to Improve Obstructive Sleep Apnea Syndrome

Supraglottoplasty for occult laryngomalacia resulted in statistically significant reduction in the apnea-hypopnea index. Overall, 91% of children had an improvement in AHI, and 64% had only mild or no residual OSAS after supraglottoplasty. Supraglottoplasty is an effective technique for the treatment of OSAS associated with occult laryngomalacia.

More Codeine Fatalities After Tonsillectomy in North American Children

In 2009 the fatal case of a toddler who had received codeine after adenotonsillectomy for OSA syndrome was first reported. The child was an ultra-rapid metabolizer of cytochrome P4502D6 (CYP2D6). Three additional fatal or life-threatening cases are now reported. In the 2 fatal cases, functional gene duplications encoding for CYP2D6 caused a significantly greater production of potent morphine from its parent drug, codeine. A severe case of respiratory depression in an extensive metabolizer is also noted. These cases demonstrate that analgesia with codeine or other opioids that use the CYP2D6 pathway after adenotonsillectomy may not be safe in young children with OSA syndrome.