Time course changes in insulin sensitivity during cardiac surgery: A retrospective study on intraoperative glycemic management using an artificial pancreas.

INTRODUCTION: Glycemic control is essential for improving the prognosis of cardiac surgery, although precise recommendations have not yet been established. Under a constant blood glucose level, the insulin infusion rate correlates with insulin resistance during glycemic control using an artificial pancreas (AP). We conducted this retrospective study to elucidate changes in intraoperative insulin sensitivity as a first step to creating glycemic control guidelines. METHODS: Fifty-five cardiac surgery patients at our hospital who underwent intraoperative glycemic control using an AP were enrolled. Twenty-three patients undergoing surgical procedures requiring cardiac arrest under hypothermic cardiopulmonary bypass (CPB) with minimum rectal temperatures lower than 32°C, 13 patients undergoing surgical procedures requiring cardiac arrest under hypothermic CPB with minimum rectal temperatures of 32°C, eight patients undergoing on-pump beating coronary artery bypass grafting and 11 patients undergoing off-pump coronary artery bypass were assigned to groups A, B, C and D, respectively. We analyzed the time course of changes in the data derived from glycemic control using the AP. RESULTS: Significant time course changes were observed in groups A and B, but not in groups C and D. Insulin resistance was induced after the start of hypothermic CPB in groups A and B, and the induced change was not resolved by the rewarming procedure, remaining sustained until the end of surgery. CONCLUSIONS: Hypothermia is the predominant factor of the induced insulin resistance during cardiac surgery. Thus, careful glycemic management during hypothermic CPB is important. Prospective clinical studies are required to confirm the findings of this study.

Successful airway management with combined use of a McGRATHTM MAC videolaryngoscope and fiberoptic bronchoscope in a patient with congenital tracheal stenosis diagnosed in adulthood.

BACKGROUND: Most patients with congenital tracheal stenosis (CTS) develop respiratory symptoms early in life. CTS remaining undiagnosed until adulthood is rare. CASE PRESENTATION: A 51-year-old female was scheduled for cardiovascular surgery. She had undergone laparoscopic surgery 3 years earlier and was found to have a difficult airway. Postoperatively, she was diagnosed with CTS. For the current cardiovascular surgery, combined use of a McGRATHTM MAC videolaryngoscope and fiberoptic bronchoscope allowed sufficient visualization of the glottis and trachea, resulting in successful intubation. CONCLUSIONS: CTS patients have a high probability of difficult intubation. Our experience suggests the efficacy of combined use of a videolaryngoscope and fiberoptic bronchoscope for airway management in CTS patients.

[Combined Use of a Videolaryngoscope and a Transilluminating Device for Intubation with Two Difficult Airways].

Videolaryngoscope is useful in patients with difficult airways, but it may not be in some patients. We report the use of a lighted stylet to facilitate tracheal intubation in 2 patients in whom laryngoscopy with a videolaryngoscope was difficult. Case 1: A 52-year-old female with loose teeth and lockjaw presented for a scoliosis surgery under general anesthesia. Laryngoscopy using a blade 3 of a Glide-Scope® (Laerdal Medical Corporation, New York, NY, USA) videolaryngoscope (GVL) showed a Cormack-Lehanne grade 3 view. Bag mask ventilation was easily achieved. By using the Trachilight™ (Saturn Biomedical System Burnaby, BC, Canada) with the GVL, we could intubate the trachea succesfully. Case 2: A 16-year-old male with a history of difficult tracheal intubation due to a limited cervical spine movement presented for an external fixation of a femur under general anesthesia. After induction of anaesthesia, bag mask ventilation was easily achieved but the GVL laryngoscopy did not provide a good view of the glottis (Cormack-Lehanne grade 3). Combined use of the Trachilight™ with the GVL, facilitated tracheal intubation. The Trachilight™ is a recognized aid to facilitate trachal intubation but the device is now commercially not available. Neverthless, we believe that a lighted stylet is potentially useful for tracheal intubation when the view of the glottis with a videolaryngoscopy is not ideal.

Effects of acetate on lipid metabolism in muscles and adipose tissues of type 2 diabetic Otsuka Long-Evans Tokushima Fatty (OLETF) rats.

We have reported that orally administrated acetate contributed to suppression of lipogenesis in the liver and to reduction of lipid accumulation in the adipose tissue of Otsuka Long-Evans Tokushima Fatty (OLETF) rats. The aim of this study was to investigate the effect of acetate on skeletal muscle and adipose tissues. Treatment with acetate showed a higher rate of oxygen consumption and a smaller size of lipid droplets in white adipose and brown adipose tissues. An analysis by Northern blotting revealed that the transcripts of myoglobin and Glut4 genes in the abdominal muscle of the OLETF rats were increased by acetate treatment, while the transcripts of lipolytic genes increased in the white adipose and brown adipose tissues. It is possible that acetate has effects on lipid metabolism in the skeletal muscles and the adipose tissues, and has functions that work against obesity and obesity-linked type 2 diabetes.