Nasotracheal intubation is used as a basic method for airway management, along with orotracheal intubation under anesthesia and intensive care. It has become an effective alternative method to orotracheal intubation with increased benefits of offering better mobility and surgical field in oral and maxillofacial surgery and possibly in trauma and critically ill patients. Nasotracheal intubation is performed through a relatively narrow nasal cavity; therefore, additional precautions are needed. Accordingly, nasotracheal intubation methods have evolved over the years with accumulated clinical experience and improved instruments to facilitate safe intubation with reduced complications. Therefore, in this review article, we summarize the basic anatomy of the nasal airways to clarify the precautions, delineate the history and development of various methods and instruments, and describe the indications, contraindications, complications, and preventive methods of nasotracheal intubation.

Kim YB, et al. Korean J Anesthesiol. 2017 Oct;70(5):500-510. https://doi.org/10.4097/kjae.2017.70.5.500

Koh W, et al. Korean J Anesthesiol. 2016 Jun;69(3):244-249. http://dx.doi.org/10.4097/kjae.2016.69.3.244

Dantrolene sodium (DS) was first introduced as an oral antispasmodic drug. However, in 1975, DS was demonstrated to be effective for managing malignant hyperthermia (MH) and was adopted as the primary therapeutic drug after intravenous administration. However, it is difficult to administer DS intravenously to manage MH. MH is life-threatening, pharmacogenomically related, and induced by depolarizing neuromuscular blocking agents or inhalational anesthetics. All anesthesiologists should know the pharmacology of DS. DS suppresses Ca2+ release from ryanodine receptors (RyRs). RyRs are expressed in various tissues, although their distribution differs among subtypes. The anatomical and physiological functions of RyRs have also been demonstrated as effective therapeutic drugs for cardiac arrhythmias, Alzheimer’s disease, and other RyR-related diseases. Recently, a new formulation was introduced that enhanced the hydrophilicity of the lipophilic DS. The authors summarize the pharmacological properties of DS and comment on its indications, contraindications, adverse effects, and interactions with other drugs by reviewing reference articles.

BACKGROUND Magnesium potentiates the effects of nondepolarising muscle relaxants. However, few studies have used magnesium chloride (MgCl2). Sugammadex reverses neuromuscular block by steroidal nondepolarising muscle relaxants. OBJECTIVES To assess the effects of MgCl2 on rocuronium-induced neuromuscular blockade and its reversal by sugammadex. DESIGN In-vitro experimental study. SETTING Animal laboratory, Asan Medical Center, Seoul, South Korea, from 20 March 2016 to 3 April 2016. ANIMALS Forty male Sprague Dawley rats. INTERVENTION Left phrenic nerve-hemidiaphragms from 40 Sprague Dawley rats were allocated randomly to four groups (1, 2, 3 and 4mmol l(-1) MgCl2 group, n = 10 each). Rocuronium was administered cumulatively until the first twitch of train-of-four (TOF) disappeared completely. Then, equimolar sugammadex was administered. MAIN OUTCOME MEASURES The effective concentration (EC) of rocuronium was obtained in each group. After administering sugammadex, recovery of the first twitch height and the TOF ratio were measured for 30 min. RESULTS EC50, EC90 and EC95 significantly decreased as the concentration of MgCl2 increased (all P <= 0.001), except the comparison between the 3 and 4 mmol l(-1) MgCl2 groups. After administration of sugammadex, the maximal TOF ratio (%) was lower in the 4 mmol l(-1) MgCl2 group than the 1 mmol l(-1) MgCl2 group [median 91.7 interquartile range (83.4 to 95.8) vs. 98.3 interquartile range (92.2 to 103.4), P = 0.049]. The mean time (s) from sugammadex injection to achieving maximal first twitch was significantly prolonged in the 4 mmol l(-1) MgCl2 group vs. the 1 mmol l(-1) MgCl2 and 2 mmol l(-1) MgCl2 groups [1483.9 (+/- 237.0) vs. 1039.0 (+/- 351.8) and 926.0 (+/- 278.1), P = 0.022 and 0.002, respectively]. CONCLUSION Increases in MgCl2 concentration reduce the ECs of rocuronium. In addition, administering sugammadex equimolar to the administered rocuronium shows limited efficacy as MgCl2 concentration is increased.