Power Spectral Analysis of Heart Rate Variability during Total Spinal Anesthesia in Rats / 대한마취과학회지

BACKGROUND: Total spinal anesthesia (TSA) anesthetizes cranial nerves as well as peripherial nerves, leading to specific circulatory perturbations related to autonomic imbalance between sympathetic and parasympathetic tone. Heart rate variability (HRV) result from moment-to-moment changes in sympathetic and parasympathetic activity in response to many conditions. Using a power spectral analysis of heart rate variability, we evaluated the effect of TSA on the changes in the autonomic nervous system. METHODS: Twenty-four Sprague-Dawley rats, during halothane anesthesia, were placed in a stereotaxic head holder. Polyethylene tubing (PE-10) was passed caudally from the cisterna magna, and these rats were anesthetized by a urethane intraperitoneal injection (1.5 g/kg). Succinylcholine was infused intravenously at 1 mg/kg/min. During mechanical ventilation, ECG signals and mean arterial blood pressure were recorded for 5 min after a period of 10 min of anesthetic stabilization (baseline). Lidocaine (40 mg/kg) was administered intrathecally and then two subsequent 5-min ECG signals and mean arterial blood pressure were recorded (TSA 0 5 min, 5 10 min). A power spectral analysis of the data was computed using a short-time Fourier transform. The spectral peaks within each measurement were calculated; low frequency area (0.25 0.75 Hz), high frequency area (0.75 3.0 Hz), total frequency area (0.25 3.0 Hz). RESULTS: Mean R-R interval increases progressively during the 5 minutes after TSA but mean blood pressure decreases to the level of blood pressure of TSA within 2 minutes after TSA (p < 0.05). TSA diminished HRV within 2 minutes after a spinal injection of lidocaine (p < 0.05). CONCLUSIONS: These results suggest that total spinal anesthesia depresses both sympathetic and parasympathetic tone within 2 minutes.

Intubating Layngeal Mask Airway in Awake Intubation / 대한마취과학회지

The incidence of difficult intubation varies from 1.5% to 13%, and failed intubation has been identified as one of the anesthesia-related causes of death or permanent brain damage. The Intubating Laryngeal Mask Airway (ILMA) is a new modified laryngeal mask airway with the capability for guided tracheal intubation while maintaining ventilation. The ILMA was designed to improve blind endotracheal intubation through a laryngeal mask airway. It does not require head and neck manipulations on insertion. The success rate of blind intubation using the ILMA was up to 99.3% in patients with or without airway problems. We experienced two cases of the difficult endotracheal intubation due to cervical spine 1 2 fractured 34 years old female patient and cervical spine 5 6 fractured 62 years old female patient were done successful awake airway management through the ILMA with superior laryngeal nerve block with pharyngeal and endotracheal topical spray of lidocaine. These cases suggest that awake tracheal intubations through the ILMA is a safe and useful method for airway management in anesthetic care of cervical spine fracture patients.

Noninvasive Regional Cerebral Oxygenation Monitoring in Patients with Moyamoya Disease / 대한마취과학회지

Moyamoya disease is a rare progressive occlusive disease in the internal carotid arteries, along with the presence of an abnormal capillary network of vessels at the base of the brain. In moyamoya disease, the manitaining of cerebral perfusion and cerebral oxygen saturation are required to reduce complications of this disease including cerebral ischemia and cerebral hemorrhage. The authors measured regional oxygen saturation (rSO2) nonivasively by INVOS 5100 (Somanetics, USA) in patients with moyamoya disease who were scheduled for an encephalo-duro-arterio-myo synangiosis (EDAMS) operation. We therefore report our findings that deep breathing decreased rSO2 and oxygen, elevated blood pressure, and that the cerebral vasodilating drug increased rSO2.