BACKGROUND: Dexmedetomidine is a highly selective alpha2-adrenoceptor agonist that is widely used for sedation and analgesia during the perioperative period. Intravenous administration of dexmedetomidine induces transient hypertension due to vasoconstriction via the activation of the alpha2-adrenoceptor on vascular smooth muscle. The goal of this in vitro study is to investigate the calcium-dependent mechanism underlying dexmedetomidine-induced contraction of isolated endothelium-denuded rat aorta. METHODS: Isolated endothelium-denuded rat thoracic aortic rings were suspended for isometric tension recording. Cumulative dexmedetomidine concentration-response curves were generated in the presence or absence of the following inhibitors: alpha2-adrenoceptor inhibitor rauwolscine; voltage-operated calcium channel blocker verapamil (5 x 10(-7), 10(-6) and 5 x 10(-5) M); purported inositol 1,4,5-trisphosphate receptor blocker 2-aminoethoxydiphenylborate (5 x 10(-6), 10(-5) and 5 x 10(-5) M); phospholipase C inhibitor U-73122 (10(-6) and 3 x 10(-6) M); and store-operated calcium channel inhibitor gadolinium chloride hexahydrate (Gd3+; 5 x 10(-6) M). Dexmedetomidine concentration-response curves were also generated in low calcium concentrations (1 mM) and calcium-free Krebs solution. RESULTS: Rauwolscine, verapamil, and 2-aminoethoxydiphenylborate attenuated dexmedetomidine-induced contraction in a concentration-dependent manner. Low calcium concentrations attenuated dexmedetomidine-induced contraction, and calcium-free Krebs solution nearly abolished dexmedetomidine-induced contraction. However, U-73122 and Gd3+ had no effect on dexmedetomidine-induced contraction. CONCLUSIONS: Taken together, these results suggest that dexmedetomidine-induced contraction is primarily dependent on extracellular calcium concentrations that contribute to calcium influx via voltage-operated calcium channels of isolated rat aortic smooth muscle. Dexmedetomidine-induced contraction is mediated by alpha2-adrenoceptor stimulation. Dexmedetomidine-induced contraction appears to be partially mediated by calcium release from the sarcoplasmic reticulum.
Administration, Intravenous ; Analgesia ; Animals ; Aorta ; Calcium ; Calcium Channels ; Contracts ; Dexmedetomidine ; Estrenes ; Gadolinium ; Hypertension ; Inositol 1,4,5-Trisphosphate ; Isotonic Solutions ; Muscle, Smooth ; Muscle, Smooth, Vascular ; Perioperative Period ; Pyrrolidinones ; Rats ; Sarcoplasmic Reticulum ; Type C Phospholipases ; Vasoconstriction ; Verapamil ; Yohimbine

BACKGROUND: The aim of this study was to evaluate the effect of aging on the hemodynamic response to endotracheal intubation during the induction of anesthesia. METHODS: Fifty patients with American Society of Anesthesiologists physical status classification 1 or 2 were enrolled and allocated according to age to either group N (35-44 years, not elderly, n=25) or group E (65-74 years, elderly, n=25). The patients were administered 3 minimum alveolar concentrations of sevoflurane for 5 minutes for the induction of anesthesia. Systolic arterial pressure (SAP) and heart rate (HR) were recorded before (baseline), immediately after (T0), and at 1-minute intervals during the first 4 minutes after endotracheal intubation (T1-T4). RESULTS: SAP increased by 15.4% and 10.8%(p<0.05) from the baseline at T0 and T1, respectively, in group N, and by 21.6%, 17.8%, and 11.8%(p<0.05) from the baseline at T0, T1 and T2 respectively, in group E. The SAP increases at T0, T1 and T2 were significantly greater in group E than in group N (p<0.05). The HR increases at T0 and T1 were significantly greater for group N than for group E (p<0.05). CONCLUSION: We recommend that anesthesiologists vigilantly monitor and attenuate adverse hemodynamic responses for at least 5 minutes after endotracheal intubation especially in elderly patients, particularly because significant systolic hypertension can occur in this age group.
Aged ; Aging* ; Anesthesia* ; Arterial Pressure ; Classification ; Heart Rate ; Hemodynamics* ; Humans ; Hypertension ; Intubation ; Intubation, Intratracheal*

BACKGROUND AND OBJECTIVES: Viral and vascular disorders are considered to be a major cause of idiopathic sudden sensorineural hearing loss (ISSNHL). Lipoprostaglandin E₁ (lipo-PGE₁) has vasodilating activity and has been used to treat ISSNHL. The purpose of this study was to determine the specific therapeutic effects of lipo-PGE₁ and compare them to other treatment modalities for ISSNHL. SUBJECTS AND METHODS: The study group had 1,052 patients diagnosed with ISSNHL. All were treated with steroid, carbogen inhalation, stellate ganglion block (SGB), or PGE₁. The CP group (steroid, carbogen inhalation, and PGE1 injection; 288 patients) was treated with lipo-PGE₁ and carbogen inhalation, the CS group (steroid, carbogen inhalation, and stellate ganglion block; 232 patients) with steroid, carbogen inhalation, and SGB, the C group (steroid and carbogen inhalation; 284 patients) with steroid and carbogen, and the control group (steroid only; 248 patients) with steroid only. Patients in the groups receiving lipo-PGE₁ received a continuous infusion of 10 µL lipo-PGE₁. RESULTS: The overall recovery rate after treatment was 52.2%, and recovery rates by group were 67.7% in the CP group, 54.3% in the CS group, 52.1% in the C group, and 32.2% in the control group. Therefore, the therapeutic results in groups treated with lipo-PGE₁ were better than results in other groups. The difference was statistically significant. CONCLUSIONS: The study results suggested that the CP group received effective treatment modalities for ISSNHL. The combined therapy of lipo-PGE₁ with carbogen inhalation in patients with ISSNHL was more beneficial than other treatment modalities.
Alprostadil ; Hearing Loss, Sensorineural* ; Humans ; Inhalation ; Stellate Ganglion ; Therapeutic Uses*

Recently, laparoscopic techniques are being increasingly used for retroperitoneal surgery. These procedures are considered relatively safe and non-invasive, however, there exists a small but important risk of developing complications related to insufflation with carbon dioxide (CO2). A 51-year-old female patient was admitted for retroperitoneal laparoscopic nephrectomy under general anesthesia. About 60 minutes after carbon dioxide pneumoperitoneum, the patient's oxygen saturation decreased. A chest x-ray was taken in the operating room, which showed pneumothorax in the right lung. We concluded that anesthesiologists should be aware of the occurrence of pneumothorax during the retroperitoneal laparoscopic procedure careful monitoring and appropriate management are needed.
Anesthesia, General ; Carbon Dioxide ; Female ; Humans ; Insufflation ; Laparoscopy ; Lung ; Middle Aged ; Nephrectomy* ; Operating Rooms ; Oxygen ; Pneumoperitoneum ; Pneumothorax* ; Thorax

BACKGROUND: The authors performed this study to investigate the hemodynamic effect of nicardipine using an esophageal Doppler monitor (EDM) during gynecologic laparoscopic surgery. METHODS: Forty patients scheduled to undergo gynecologic laparoscopic surgery, were divided into two groups; the control group (Group C) and the nicardipine group (Group N). Pneumoperitoneum was initiated using CO2 gas and the intraperitoneal pressure was kept under 12 mmHg. Hemodynamic parameters at critical points were measured using EDM, i.e., before skin incision (T1), 5, 10 and 15 min after the initiation of pneumoperitoneum (T2, T3 and T4), and 5 min after deflation (T5). RESULTS: Mean arterial pressure (MAP) was significantly lower in Group N patients than in Group C patients at 5 and 10 min after the initiation of pneumoperitoneum (T2 and T3) (P < 0.05). No significant heart rate (HR) differences were observed between the two study groups. Cardiac output (CO), peak velocity (PV) and corrected flow time (FTC) were significantly higher in Group N at 10 min after the initiation of pneumoperitoneum (T3) (all P < 0.05). CONCLUSIONS: The nicardipine continuous infusion at 0.5?2.0microg/ kg/min is effective at attenuating hemodynamic changes after pneumoperitoneum during gynecologic laparoscopic surgery.
Arterial Pressure ; Cardiac Output ; Heart Rate ; Hemodynamics ; Humans ; Laparoscopy ; Nicardipine ; Organothiophosphorus Compounds ; Pneumoperitoneum ; Skin

BACKGROUND: The goal of this study was to determine the optimal target-controlled concentration of remifentanil combined with desflurane, by using a more widely and decreasing end-tidal concentration of desflurane. METHODS: Ninety ASA I patients, who underwent general anesthesia for elective orthopedic or extremity surgeries, were registered and randomly allocated to receive either a target-controlled concentration of 1 ng/ml (group R1), 2 ng/ml (group R2) remifentanil, or desflurane only without remifentanil infusion (group D). Mean arterial pressure (MAP) and heart rate (HR) were recorded at 5-min intervals from after a 10-15 min period of surgical incision to before a 10-min period prior to the end of an operation. End-tidal concentration of desflurane was increased or decreased in proportion to the changes in MAP and HR. If the value of bispectral index (BIS) was from 60-62 for more than 2 min or systolic blood pressure would fall below 90 mmHg, the patient was excluded from the study to prevent a risk of "explicit awareness" and shock. RESULTS: The end-tidal desflurane concentration was lower in the group receiving 1 ng/ml (5.2 +/- 0.5 vol%; P < 0.001) and 2 ng/ml remifenanil (4.4 +/- 0.5 vol%; P < 0.001) compared to patients in group D (7.9 +/- 0.5 vol%). CONCLUSIONS: We recommend the use of 2 ng/ml or less remifentanil combined with desflurane for decreasing concentrations of desflurane without significant side effects, during the "maintenance" phase, and not during the induction phase of general anesthesia.
Anesthesia, General ; Arterial Pressure ; Blood Pressure ; Extremities ; Heart Rate ; Humans ; Isoflurane ; Orthopedics ; Piperidines

BACKGROUND AND OBJECTIVES: Esophageal perforation is relatively uncommon and requires careful diagnostic evaluation and expert management. It has a high mortality due to significant mediastinal and pleural contamination leading to sepsis and multiple organ failure. We reviewed our experience of esophageal perforation to determine how to better recognize such a lesion and facilitate its correct management. SUBJECTS AND METHOD: A retrospective chart review was performed on all patients treated for esophageal perforation from January 2000 to March 2016. These patients have been studied with respect to gender and age distribution, causes, sites, clinical manifestation, complications, management and postoperative complications. RESULTS: Patients ranged in age from 21 to 87 years, with an average age of 57.6±12.4 years. Fifty of the patients were men and 21 were women. The causes of the perforations were as follows: foreign body retention (18 patients), trauma (17 patients), Boerhaave's syndrome (22 patients), and iatrogenic (14 patients). The sites of esophageal perforation were: the cervical esophagus (25 patients), thoracic esophagus (44 patients) and abdominal esophagus (2 patients). Primary repair only was performed in seven (9.9%) patients, whereas 32 (45%) patients were treated with primary repair & patch, seven (9.9%) patients with T-tube drainage. Exclusion & division were performed in three (4.2%) patients and esophagectomy was performed in two (2.8%) patients. Twenty (28.2%) patients were treated conservatively. CONCLUSION: Early recognition and appropriate management of esophageal perforation are essential for reduction of morbidity and mortality.
Age Distribution ; Drainage ; Esophageal Perforation* ; Esophagectomy ; Esophagus ; Female ; Foreign Bodies ; Humans ; Male ; Methods ; Mortality ; Multiple Organ Failure ; Postoperative Complications ; Retrospective Studies ; Sepsis

Tethered cord syndrome is a form of spinal dysraphism, with a low-lying conus frequently associated with an intraspinal lipoma, diastematomyelia or fibrous band. The clinical manifestations include spine abnormalities, such as spina bifida, or various neurological symptoms involving the lower extremities and sphincters. Herein, our experience of a 42-year-old female tethered cord syndrome patient, with deficit, paresthesia and incontinence following spinal anesthesia for anti-incontinence surgery, is reported with a brief review of literature.
Adult ; Anesthesia, Spinal* ; Conus Snail ; Female ; Humans ; Lipoma ; Lower Extremity ; Neural Tube Defects* ; Paresthesia ; Spinal Dysraphism ; Spine

Myotonic dystrophy is an autosomal-dominant inherited neuromuscular disorder that's characterized by slowly progressive muscular dystrophy, muscle weakness and myotonia. The clinical features may vary from just cataracts to involvement of multiple organ systems such as various muscles, the heart, lung and intestine. Its most common complication is postoperative respiratory failure. We encountered a patient who developed sudden unexpected peripartum cardiomyopathy (PPCM) and respiratory failure due to presumed myotonic dystrophy after cesarean section. We report here on our clinical experience with this malady and we include a brief review of the medical literature on myotonic dystrophy.
Cardiomyopathies ; Cataract ; Cesarean Section ; Female ; Heart ; Humans ; Intestines ; Lung ; Muscle Weakness ; Muscles ; Muscular Dystrophies ; Myotonia ; Myotonic Dystrophy ; Peripartum Period ; Pregnancy ; Respiratory Insufficiency

BACKGROUND: Studies have shown that tracheal intubation can be facilitated safely and effectively after induction of anesthesia with hypnotic and opioid without employing any muscle relaxants. Remifentanil is a new, ultra-short acting, selective mu-receptor agonist. The goal of our present study was to evaluate the appropriate induction dose of remifentanil with propofol for tracheal intubation without employing any muscle relaxants. METHODS: We have assessed intubating conditions in three groups of 45 ASA I or II Patients. Each group received intravenous dosage of 2 mg/kg of propofol with remifentanil 1microgram/kg (Group I), 2microgram/kg (Group II) or 3microgram/kg (Group III), respectively. No muscle relaxant was administered. Intubating conditions were assessed based on jaw relaxation, vocal cord position, vocal cord movement, airway reaction, and movement of limbs. Intubating conditions, mean arterial blood pressure and heart rate were measured just before induction (T00, baseline), before intubation (T0), 1 minute after intubation (T1), 2 minutes after intubation (T2) and 3 minutes after intubation (T3). RESULTS: Intubating conditions were clinically acceptable in 26.7, 86.7 and 93.3% of patients, after 1, 2 or 3microgram/kg administration of remifentanil, respectively. Clinically acceptable intubating conditions were significantly more in Group II and III when compared with Group I (P<0.05). Both HR (heart rate) and MAP (mean arterial pressure) were significantly lower in Group III when compared with Group I before intubation (T0), 1 minute after intubation (T1), 2 minutes after intubation (T2) and 3 minutes after intubation (T3) (P<0.05). CONCLUSIONS: We conclude that 2-3microgram/kg of remifentanil may reliably provide 'good' to 'excellent' conditions for tracheal intubation when administered after administration of 2 mg/kg propofol. The conditions for intubation were significantly better in patients receiving 2 mg/kg of propofol followed by 2-3microgram/kg of remifentanil than those receiving 1microgram/kg of remifentanil.
Anesthesia ; Arterial Pressure ; Extremities ; Heart Rate ; Hemodynamics* ; Humans ; Intubation* ; Jaw ; Propofol* ; Relaxation ; Vocal Cords