The effect of various dilute administration of rocuronium bromide on both vascular pain and pharmacologic onset: a randomized controlled trial.

BACKGROUND: Rocuronium bromide (RB) is known to cause vascular pain. Although there have been a few reports that diluted administration causes less vascular pain, there have been no studies investigating diluted administration and the onset time of muscle relaxation. Therefore, we examined the influence of diluted administration of RB on the onset time of muscle relaxation and vascular pain. METHODS: 39 patients were randomly assigned to three groups: RB stock solution 10 mg/ml (Group 1), two-fold dilution 5 mg/ml (Group 2), or three-fold dilution 3.3 mg/ml (Group 3). After the largest vein of the forearm was secured, anesthesia was induced by propofol and 0.6 mg/kg of RB was administered. The evaluation method devised by Shevchenko et al. was used to evaluate the degree of vascular pain. The time from RB administration until the maximum blocking of T1 by TOF stimulation was measured. RESULTS: There was no significant difference in escape behaviors of vascular pain among the three groups, and the onset time of muscle relaxation was significantly slower in Group 3 than in Group 1 (p = 0.033). CONCLUSION: Our results suggested that it is unnecessary to dilute RB before administration if a large vein in the forearm is used. TRIAL REGISTRATION: UMINCTR Registration number UMIN000026737 . Registered 29 Mar 2017.

Comparison of disinfection effect between benzalkonium chloride and povidone iodine in nasotracheal intubation: a randomized trial.

BACKGROUND: Nasotracheal intubation can potentially result in microbial contamination from the upper respiratory tract to the lower respiratory tracts. However, an ideal nasotracheal disinfection method is yet to be determined. Therefore, we compared the disinfection effects between benzalkonium chloride and povidone iodine in nasotracheal intubation. METHODS: Overall, this study enrolled 53 patients aged 20-70 years who were classified into classes 1 and 2 as per American Society of Anesthesiologists-physical status and were scheduled to undergo general anesthesia with NTI. Patients who did not give consent (n = 2) and who has an allergy for BZK or PVI were excluded from the study. The patients were randomly divided into two groups on the basis of the disinfection method: BZK (n = 26, one patient was discontinued intervention) and PVI (n = 25). 50 patients were assessed finally. The subjects' nasal cavities were swabbed both before (A) and after disinfection (B), and the internal surface of the endotracheal tube was swabbed after extubation (C). The swabs were cultured on Brain heart infusion agar and Mannitol salt agar. The number of bacteria per swab was determined and the rates of change in bacterial count (B/A, C/B) were calculated. The growth inhibitory activity of the disinfectants on Staphylococcus aureus were also investigated in vitro. RESULTS: Although the initial disinfection effects (B/A) were inferior for benzalkonium chloride compared with those for povidone iodine, the effects were sustained for benzalkonium chloride (C/B). In the in vitro growth inhibitory assay against S. aureus, benzalkonium chloride showed higher inhibitory activity than povidone iodine. CONCLUSION: Although both disinfectants were inactivated or diffused/diluted over time, benzalkonium chloride maintained the threshold concentration and displayed antimicrobial effects longer than povidone iodine; therefore, benzalkonium chloride appeared to show a better sustained effect. Benzalkonium chloride can be used for creating a hygienic nasotracheal intubation environment with sustained sterilizing effects. TRIAL REGISTRATION: UMIN-CTR (Registration No. UMIN000029645 ). Registered 21 Oct 2017.

[Undetected of Esophageal Intubation for Two Hours of Cardiopulmonary Resuscitation].

Securing of airway is one of the most important issues during cardiopulmonary resuscitation, and oro- tracheal intubation has been a gold standard proce- dure. We experienced a case in which the esophageal intubation was overlooked for 2 hours after the intuba- tion at the bedside of general ward and in the inten- sive care unit A 71-year-old male patient without marked medical history was transferred to our hospital with severe symptom of lower gastrointestinal ileus. After admitting to the ward, transrectal drainage tube was placed. On the night of the admission, the patient called the staff from his bed ; however, he lost con- sciousness and monitoring electrocardiogram showed sudden bradycardia followed by cardiac arrest Emer- gency cardiopulmonary resuscitation was initiated and the intubation was conducted by the physician on call. The cardiovascular status was unstable despite recov- ery of spontaneous circulation (ROSC) and the patient was transferred to the intensive care unit The arrest and ROSC by resuscitation was repeated. After 2 hours from the start of resuscitation, temporal ROSC was obtained, but the absence of a wave of capnogram was identified. The observation using laryngoscopy revealed esophageal intubation and oro-tracheal intuba- tion was facilitated. Although the mechanical ventila- tion was established, the condition of the patient dete- riorated with pulseless electrical activity followed by death.

Radial artery cannulation decreases the distal arterial blood flow measured by power Doppler ultrasound.

Radial arterial cannulation is a popular technique for continuous hemodynamic monitoring in an area of anesthesia and intensive care. Although the risk for invasive monitoring is considerable, there is scarce information about the change in blood flow of cannulated vessel after the catheterization. In the current investigation, we evaluated the change in the cannulated arterial blood flow. Six volunteers (study 1) and eight post-surgical patients (study 2) were enrolled into the studies. In the study 1, the both side of diameter of radial artery (RA), ulnar artery (UA) and dorsal branch of radial artery (DBRA) of participants were measured using power Doppler ultrasound (PDU) with or without proximal oppression. In the study 2, the diameter of RA, UA and DBRA of the both intact and cannulated side were compared. Study 1: The diameter of RA was 3.4 (0.52) [mean (SD)] mm and the proximal oppression significantly decreased the diameter to 1.8 (0.59) mm. The diameter of DBRA measured by PDU also decreased 2.0 (0.60)-1.3 (0.59) mm. Study 2: There was no difference between the diameters of right and left RA, however, the UA was larger [3.4 (0.60) vs. 2.8 (0.83) mm] and the DBRA was narrower [1.4 (0.43) vs. 2.0 (0.47) mm] in the cannulated side. The diameters of DBRA were different between the intact and cannulated side in the patients. Although there is no information of relationships between cause of severe complication and decreased flow, significant reduction of blood flow should be concerned.

Dexmedetomidine-induced atrioventricular block followed by cardiac arrest during atrial pacing: a case report and review of the literature.

Sinus bradycardia is a well-known consequence of stimulation of presynaptic α2 adrenergic receptors due the adminstration of dexmedetomidine. One of the most serious adverse effects of dexmedetomidine is cardiac arrest. Some cases demonstrating such an arrest due to the indiscriminate use of this drug were recently reported. We continuously administered dexmedetomidine to a 56-year-old male patient at a rate of 0.3 µg/kg/h (lower than the recommended dose) without initial dosing for sedation in an intensive care unit. The patient had undergone open cardiac surgery and atrial pacing was maintained at a fixed rate, 90/min. The PQ interval in electrocardiography gradually prolonged during the infusion; finally, complete atrioventricular block and subsequent cardiac arrest occurred. Immediate cardiopulmonary resuscitation was carried out, including re-intubation, and recovery of spontaneous circulation was attained 15 min after the event. The patient was discharged from hospital on the 25th postoperative day without any neurological complications.

Administration of lipid emulsion reduced the hypnotic potency of propofol more than that of thiamylal in mice.

Administration in a lipid emulsion can modify the pharmacodynamics of drugs via a process known as lipid resuscitation. However, the detailed mechanism remains unclear. We studied the volume and another pharmacodynamic effect, the lipid sink, using propofol and thiamylal. Male adult mice (ddY) were intravenously administered 10 ml/kg propofol or thiamylal diluted with physiological saline, 10% soybean oil, or 20% soybean oil. The 50% effective dose (ED50) for achieving hypnosis was calculated using probit analysis. To investigate the volume effect, 0, 10, or 20 ml/kg of saline or soybean oil was administered, either simultaneously or beforehand. Next, a two- or three-fold dose of the anesthetics was administered and the durations of anesthesia were measured. Finally, at 30 s after the first injection, supplemental soybean oil was administered. The mean (± SE) ED50 values of propofol and thiamylal were 5.79 mg/kg (0.61) and 8.83 mg/kg (0.84), respectively. Lipid dilution increased the ED50 values of both anesthetics. After injection of a dose two-fold the ED50 value, the respective mean (± SD) durations of anesthesia were 125 ± 35 s and 102 ± 38 s. Supplemental administration of soybean oil significantly shortened the duration of anesthesia of propofol, but not that of thiamylal. The results indicate that administration of a lipid emulsion vitiated the anesthetic effect of propofol by reducing the non-emulsified free fraction in the aqueous phase, which may elucidate the lipid resuscitation likely caused by the lipid sink mechanism.

Dexmedetomidine and hydroxyzine synergistically potentiate the hypnotic activity of propofol in mice.

PURPOSE: Investigation into the characteristics of anesthetic interactions may provide clues to anesthesia mechanisms. Dexmedetomidine, an α(2)-adrenergic receptor agonist, has become a popular sedative in intensive care, and hydroxyzine, a histamine receptor antagonist, is well known as a tranquilizing premedication for anesthesia. However, no experimental or pharmacological evaluation has been reported concerning their combination with propofol. Thus, we studied their combined effect with a hypnotic dose of propofol in ddY mice. METHODS: Male adult mice were intravenously administered either dexmedetomidine (30 µg/kg) or hydroxyzine (5 mg/kg) with propofol (3.75-10 mg/kg) to induce hypnosis, defined as a loss of the righting reflex (LRR). Other mice were intravenously administered propofol, dexmedetomidine (300 µg/kg), or hydroxyzine (50 mg/kg) alone, and subsequent behavioral changes were observed. The 50% effective dose (ED(50)) for LRR was calculated, and the duration of LRR was determined. RESULTS: The hypnotic dose of propofol was 9.95 ± 1.04 mg/kg (ED(50) ± SEM) without combination. Dexmedetomidine and hydroxyzine reduced the ED(50) of propofol to 5.32 ± 0.57 and 5.63 ± 0.57 mg/kg, respectively. Coadministration of dexmedetomidine significantly extended LRR duration compared with propofol alone, whereas hydroxyzine significantly shortened LRR duration. A maximal dose of dexmedetomidine or hydroxyzine alone did not induce hypnosis. CONCLUSIONS: Dexmedetomidine and hydroxyzine demonstrated no hypnotic action alone; however, their coadministration potentiated the hypnotic activity of propofol. Although reduction in the dose of propofol was similar, only dexmedetomidine prolonged the duration of hypnosis.

[ECG changes after the induction of general anesthesia with remifentanil: a report of three case].

We encountered three patients who showed ECG changes, suggesting cardiac conduction abnormality, immediately after the induction of general anesthesia with remifentanil and thiamylal. The first patient was a 42-year-old man (172cm and 75kg). The second patient was a 75-year-old woman (153 cm and 62 kg) and the last patient was 16-year-old woman (166 cm and 46 kg). Remarkable past history was not noted and pre-anesthetic evaluations including 12 lead electrocardiogram demonstrated no abnormality in all patients. Immediately after the induction of anesthesia, atrioventricular dissociation, sinus arrest and atrioventricular junctional rhythm were diagnosed by monitoring electrocardiogram, respectively. The conduction abnormalities were not followed by severe bradycardia and hypotension, and observed without drug administration. In the first and second patient, sinus rhythm returned within 15 to 20 min after the induction. The junctional rhythm in the third patient continued during the operation; however, the recovery to sinus rhythm was observed at the end of operation lasting about 1 hr. No severe adverse clinical complication was found; however, careful monitoring might be required to pre vent circulatory depression with combination of remifentanil and thiamylal.

[Sudden increases and decreases in bispectral index values more than 30 within 1 minute during general anesthesia].

We described, in a 40-year-old man, sudden and unexpected increases in bispectral index values during the general anesthesia with total intravenous anesthesia using propofol in a dental surgery. The patient was administered continuous infusion of propofol and remifentanil, and intermittent supplementation of fentanyl. Immediately after the beginning of surgery, the bispectral index value increased abruptly to 90; whereas, heart rate and non-invasive blood pressure were unchanged and no physiological finding was observed. Approximately 25 min later, the value decreased to below 40 without any modification of anesthesia. The extent of unanticipated increase might be compatible with the duration of surgical procedure using dental air turbine. Therefore, the noise from surgical device might induce unpredictable change in bispectral index values.

[Pycnodysostosis: a case report].

A 53-year-old man suffered maxillar osteomyelitis and removal of sequester was scheduled under general anesthesia. Pycnodysostosis had been diagnosed in childhood and body height and weight were 148 cm and 40 kg, respectively. He presented facial dysmorphia, hypomobile mandible and narrow oral cavity. At the pre-anesthetic visit, we planned awake fiberscopic intubation before the induction of general anesthesia. On the day of surgery, however, face-mask ventilation was easily established with 100-microg dose of fentanyl. Thus, 70 mg of propofol was administered to achieve hypnosis and naso-tracheal intubation using fibrescope was accomplished. The patient's trachea was easily intubated without a decrease of pulse oximetry values and marked changes in cardiovascular parameters. Pycnodysostosis is a rare clinical entity; however, the airway difficulty was mild in the present case.

Preoperative heart rate variability analysis is as a potential simple and easy measure for predicting perioperative delirium in esophageal surgery.

BACKGROUND: Delirium is one of the most common but severe perioperative complications. Autonomic activity evaluated by heart rate variability (HRV) has been recently reported as a useful tool for prediction and for early detection of delirium in acute care medicine, especially in postoperative intensive care unit (ICU) patients. We hypothesized that HRV, by 3-lead electrocardiogram (ECG), one day prior to surgery might correlate with the presence of postoperative delirium. MATERIALS AND METHODS: This study was cohort prospective pilot study. We measured preoperative HRV and postoperative delirium in patients who underwent surgery for elective esophageal cancer. ECG of the participants was performed for 10 min 6-12 h preceding surgery. Postoperatively, patients were admitted to the ICU or critical care unit and stayed for at least 3 days. Delirium was diagnosed by psychiatrist rounds twice a day. RESULTS: Delirium was assessed for 3 days after surgery and 30 patients performed the study. Seven patients developed delirium during their ICU stay, while the remaining twenty-three did not. After HRV analysis, the preoperative high frequency power in delirium patients was significantly lower than that in non-delirium patient. Other parameters of HRV, including lower frequency power, total power and the ratio showed no statistically significant difference between the groups. CONCLUSION: The results of current study demonstrated that preoperative measurement of HRV may be a useful predictor of delirium. Further investigation could pave the way to a non-invasive, minimally stressful method of predicting postoperative delirium.

JM-1232(-) and propofol, a new combination of hypnotics with short-acting and non-cumulative preferable properties.

Drug interactions are significant in anesthesiology because drug combinations can potentially possess novel properties. The pharmacological advantages of a new combination of the benzodiazepine receptor agonist JM-1232(-) and propofol were investigated in mice. Male adult mice were administered JM-1232(-) or propofol or combinations of the two drugs intravenously. Loss of the righting reflex was evaluated as achieving hypnosis, and the time until recovery of the reflex was measured as hypnosis time. After determining the ED50, doses double and triple the ED50 of propofol were injected with JM-1232(-) to compare hypnosis time. The injections were repeated four times, and the hypnosis times were compared. Flumazenil was administered separately immediately after the last dose was injected. The ED50 values ([95% confidence interval]) for hypnosis were 3.76 [3.36-4.10] for JM-1232(-) and 9.88 [8.03-11.58] mg kg-1 for propofol. Co-administration of 0.5 and 1 mg kg-1 JM-1232(-) reduced the ED50 values of propofol to 1.76 [1.21-2.51] and 1.00 [0.46-1.86] mg kg-1, respectively. The drug combination for hypnosis produced a supra-additive interaction. Hypnosis time was significantly shorter in the groups given the mixtures compared to each hypnotic administered alone. After repeated injections, hypnosis time with the mixtures showed smaller prolongation than that with the hypnotic alone. Flumazenil completely restored the recovery time after anesthesia. The combination of JM-1232(-) and propofol showed a supra-additive interaction, and the reduced hypnotic dose contributed to a faster recovery even after multiple injections.

[Successful extubation in a patient with alacepril-induced tongue angioedema].

We describe a case of marked swelling of the tongue in a patient after a long prone position neurosurgery, who was treated for hypertension with alacepril. The tongue was not congestive and history of taking an angiotensin-converting enzyme inhibitor suggested an alacepril-induced angioedema. The day after surgery, the patient's tongue was still swollen; however, fibrescopic observation of the larynx and pharynx through the nasal cavity revealed that the edema was limited to anterior tongue, and the oral cavity and oropharynx were not involved. Although, tongue angioedema was observed, we introduced a 3-mm tube exchanger to the patient's trachea and removed the endotracheal tube. The ventilation and oxygenation were maintained, and 30 min later, the exchanger was detached. On the second postoperative day, the angioedema disappeared completely and the patient was transferred to a ward without any complication.

[Inadvertent thoracic duct puncture during right axially central venous cannulation].

A case of inadvertent thoracic duct puncture during right axially central venous cannulation is reported. The catheterization was performed under the real time ultrasound guidance technique and the coronal view image was continuously displayed. After confirming the feelings of venous puncture, clear yellow fluid was aspired into the connected syringe to the needle. Initially, an accidental thoracic puncture with subsequent pleural fluid aspiration was suspected;however, no finding of pleural effusion was observed with ultrasound imaging and computed tomography. Thus, an accidental thoracic duct puncture and the subsequent lymph fluid aspiration were suspected. Even in a right side approach for central venous catheterization, thoracic duct injury might ensure.

[Nasogastric tube syndrome suspected at the end of anesthesia].

The case of a patient who might have developed nasogastric tube syndrome at the end of anesthesia is presented. A 62-year-old woman was scheduled for a general anesthesia with fiberscopic oro-tracheal intubation because of a predicted difficult airway. After the smooth and gentle intubation without any trauma and injury, a nasogastric tube was inserted blindly. At the end of surgery, the anesthesiologists observed the pharyngeal tissue and found significant edema on the epiglottis and arytenoids. Extubation was cancelled and the patient was moved to an intensive care unit for respiratory management. On the next day, fiberscopic observation revealed a complete recovery and the endotracheal tube was removed without any difficulty. We strongly suspected the pharyngeal injury as acute nasogastric tube syndrome and an attention to this rare complication is required by anesthesiologists.

Fatal airway obstruction due to a ball-valve clot with identical signs of tension pneumothorax.

Endo-tracheal tube obstruction due to an extensive blood clot is a recognized but very rare complication. A ball-valve obstruction in the airway could function as a check valve for the lung and thorax, resulting in tension pneumothorax-like abnormalities. A 47-year-old female patient had undergone implantation of a left ventricular assist device 3 weeks prior. On post-operative day 17, planned thoracentesis was performed for drainage of a pleural effusion. Despite the drainage, the patient's oxygenation did not improve, and emergency tracheal intubation was conducted. Subsequent computed tomography revealed bilateral pneumothorax. Two days later, the patient's trachea was extubated without complication, and a mini-tracheostomy tube was placed. Three hours later, reintubation was conducted due to progressive tachypnea. Although successful intubation was confirmed, ventilation became increasingly difficult and finally impossible. Marked increase in pulmonary artery and central venous pressures suggested progression of the previous tension pneumothorax. After emergency extracorporeal membrane oxygenation was initiated, fiberoptic bronchoscopy revealed the presence of a massive clot and ball-valve obstruction of the endotracheal tube. Two weeks later, the patient died due to severe hypoxic brain damage. Diagnosis of ball valve clot is not simple, but intensivists should consider this rare complication.

Aspiration of massive free air from a large bore intravenous catheter sheath: A case report.

We firstly experienced a rare case demonstrating that massive volume of free air was aspirated from a large bore intravenous catheter sheath of the pulmonary arterial catheter during placement. A 44-year-old male patient underwent the emergency induction of anesthesia for transplantation of liver donated by the brain death subject. After the induction, the central venous and pulmonary artery catheter placement was conducted. The aspiration of venous blood confirmed the intravascular insertion, but massive free air was aspirated when we advanced the sheath proximally. A perforation of subclavian vein and subsequent pneumothorax was strongly suspected. The emergency computed tomography revealed no sign of pneumothorax, pneumomediastinum nor extravasation. The operation was undergone with intensive monitoring and no further adverse complication was observed. The postoperative medical inquiry concluded that the massive free air was not aspirated from extravascular space, for example, thorax or mediastinum through the tip of the sheath, but from the proximal main port of the sheath. When the tip of sheath is occluded by the migration into small vessels, the large negative pressure through side port might easily aspirate the air through the 1-way valve of the main proximal port. Physicians should keep in mind of the structure of the catheter sheath.