Isoflurane cracks the polycarbonate connector of extra-corporeal circuit: A case report / 대한마취과학회지

Cardiopulmonary bypass (CPB) is widely used for cardiac surgery by virtue of its proven safety over the course of its use during the past half century. Even though perfusion is safer, incidents still occur. During the repair of a ventricular-septal defect in an 11-month-old infant, we experienced a critical incident related to the potential hazardous effect of volatile anesthetics on the polycarbonate connector of extra-corporeal circuit. The damage to the polycarbonate connector had occurred after spillage of isoflurane during the filling of the vaporizer, causing it to crack and leak. The incident was managed by replacement of the cracked connector during a temporary circulatory arrest. The patient was hypothermic and the time off bypass was less than 1.5 min. There were no neurologic sequelae, the patient made an uneventful recovery. In conclusion, the spillage of volatile anesthetics can cause cracks in the polycarbonate connector of the extra-corporeal circuit, leading to potentially interruption of CPB.

A comparison of the consumption of inhaled anesthetics according to fresh gas flow and anesthetic circuits / 대한마취과학회지

BACKGROUND: In the Korean National Health Insurance Corporation (KNHIC), payment for inhaled anesthetics are made according to the simulated dose and not the consumed dose. We compare the consumption of inhaled anesthetics according to fresh gas flow (FGF) and anesthetic circuits to compare the consumption of anesthetics and the guidelines for KNHIC payments. METHODS: 161 patients were randomized into six groups who received isoflurane using a closed circuit (group I-C), a semi-closed circuit with FGF 3 L/min (group I-3), or 4 L/min (group I-4), as for the sevoflurane group (group S-C, S-3, and S-4). Mean arterial pressure (MAP) and heart rate (HR) were maintained within +/- 20% of baseline. Minimum alveolar concentration (MAC) and consumption of inhaled anesthetics were recorded by a new anesthetic machine. RESULTS: There were no significant differences among the groups for MAP, HR, and MAC. During anesthesia maintenance, the mean consumption per 15 minutes of inhaled anesthetics was significantly lower in group I-C (1.0 +/- 0.3 ml) than in group I-3 (3.5 +/- 0.7 ml) and than group I-4 (4.9 +/- 0.9 ml) and similar to the sevoflurane groups (group S-C [1.3 +/- 0.4 ml] vs group S-3 [5.3 +/- 1.0 ml] vs group S-4 [6.9 +/- 1.3 ml], respectively; P < 0.05). CONCLUSIONS: In sevoflurane groups, inhaled anesthetics were consumed more than in isoflurane groups. The KNHIC payment guidelines were close to the actual consumption of inhaled anesthetics under using a semi-closed circuit with FGF 3 L/min in sevoflurane and FGF 4 L/min in isoflurane.

The malfunction of self-inflating bag resuscitator due to mis-assembly: A case report / 대한마취과학회지

A self-inflating bag resuscitator is universally used to ventilate patients during cardiopulmonary resuscitation and transfer. This device can be reused after sterilization and reassembly, and the mis-assembly of a resuscitator can possibly happen. We report here on a case of mis-assembly of a resuscitator valve that resulted to barotrauma and instability of a patient.

A comparison of hemodynamics in elderly patients that were administered thiopental sodium or propofol to induce general anesthesia / 대한마취과학회지

BACKGROUND: Thiopental sodium and propofol are commonly used to induce anesthesia. This study was conducted to compare the hemodynamic effects of propofol and thiopental sodium during the induction of general anesthesia in elderly patients. METHODS: Forty patients undergoing general anesthesia were randomly divided into two groups. In group T, thiopental sodium was used to induce anesthesia, whereas propofol was used in group P. Hemodynamic changes in the mean blood pressure, heart rate, cardiac index (as determined using a NICCOMO monitor) and bispectral index (BIS) during induction were then compared between the two groups. In addition, the dosage of induction agent, time required until loss of response to verbal order (LOV) and eyelid reflex were compared between groups. RESULTS: The mean blood pressure was significantly lower in group P than in group T during the 1-5 min following LOV and during the 2, 3 min following intubation (P < 0.05). However, the heart rate did not differ significantly between the two groups. The cardiac index also did not differ significantly between groups, except during the first 3 min following LOV. Finally, the BIS value were significantly lower than the baseline values in both groups during induction. CONCLUSIONS: In elderly patients, the heart rate, cardiac index and BIS value did not differ significantly between the two groups. But the mean blood pressure was significantly lower in propofol than in thiopental sodium.

Optimal dosages of propofol and remifentanil for minimizing hemodynamic changes during laryngeal microscopic surgery / 대한마취과학회지

BACKGROUND: Laryngeal microscopic surgery (LMS) is stressful to the patient due to intubation and suspension laryngoscopy. The aim of this study was to determine the optimal dosages of propofol and remifentanil for minimizing hemodynamic changes during LMS. METHODS: Eighty outpatients undergoing LMS were randomly divided into four groups. In all patients, endotracheal intubation was done with an effect-site concentration of propofol at 3 or 4microgram/ml. Group I (propofol 3microgram/ml) and II (propofol 4microgram/ml) patients received remifentanil 0.5microgram/kg and an infusion at 0.1microgram/kg/min. Group III (propofol 3microgram/ml) and IV (propofol 4microgram/ml) patients received remifentanil 1.0microgram/kg and an infusion at 0.2microgram/kg/min. Hemodynamic changes and bispectral index (BIS) values during intubation and suspension laryngoscopy were compared among the groups. In addition, extubation time, emergence time, and state of recovery (Steward score) were compared. RESULTS: After intubation and suspension laryngoscopy, the mean arterial pressure (MAP) was significantly lower than baseline values in groups II and IV (P < 0.05). After suspension laryngoscopy, the heart rate (HR) was significantly lower than baseline value in group II (P < 0.05). Extubation time was significantly shorter in groups I, II, and III compared to group IV, and the time for responding to verbal commands was significantly shorter in groups I and II compared to group IV (P < 0.05). The incidence of hypotension was higher in group IV than in the other groups (P < 0.05). CONCLUSIONS: The results suggest that an effect-site concentration of propofol at 4microgram/ml with remifentanil 0.5microgram/kg and infusion of 0.1microgram/kg/min provide proper anesthesia with minimal hemodynamic changes during LMS.

Effective removal of epistaxis during nasotracheal intubation utilizing a fiberoptic scope in a difficult airway: A case report / 대한마취과학회지

Nasal bleeding related to nasal trauma is the most common complication of nasotracheal intubation with a fiberoptic scope. When nasotracheal intubation with a fiberoptic scope is performed, profuse bleeding from the nasal cavity makes it difficult to handle a fiberoptic scope and may cause a hypoxemia. So when nasal bleeding occurs, it is important to suction the nasal cavity for easy handling of a fiberoptic scope. But, it may be difficult to suction in a nasal cavity with a fiberoptic suction port only. We report a patient with nasal bleeding following nasotracheal intubation with a fiberoptic scope because of articular trismus, and successful nasotracheal intubation utilizing a fiberoptic scope by suctioning with an extra suction apparatus.

Effective removal of epistaxis during nasotracheal intubation utilizing a fiberoptic scope in a difficult airway: A case report / 대한마취과학회지

Nasal bleeding related to nasal trauma is the most common complication of nasotracheal intubation with a fiberoptic scope. When nasotracheal intubation with a fiberoptic scope is performed, profuse bleeding from the nasal cavity makes it difficult to handle a fiberoptic scope and may cause a hypoxemia. So when nasal bleeding occurs, it is important to suction the nasal cavity for easy handling of a fiberoptic scope. But, it may be difficult to suction in a nasal cavity with a fiberoptic suction port only. We report a patient with nasal bleeding following nasotracheal intubation with a fiberoptic scope because of articular trismus, and successful nasotracheal intubation utilizing a fiberoptic scope by suctioning with an extra suction apparatus.

The Effect of Age on the Cardiovascular Responses Induced by Inhaled High Concentration of Desflurane / 대한마취과학회지

BACKGROUND: The inhalation of high concentrations of desflurane transiently increases the cardiovascular responses. This study examined the effects of age on the cardiovascular response to desflurane. METHODS: Eighty two patients were divided into one of three groups: under 3 years (Group 1), 2050 years (Group 2), and over 65 years (Group 3). In each group, the inspired concentration of desflurane was increased abruptly to 12.0 vol% 2 minutes after a thiopental injection. The heart rate, blood pressure (BP), cardiac index (CI), End-tidal concentration of desflurane (ETdesf), and end-tidal concentration of CO2 were measured at the baseline and every 30 seconds. RESULTS: The heart rate, BP, and CI increased transiently in the three groups compared with the baseline. The ETdesf increased more rapidly in Groups 1 and 3 than in Group 2. The ETdesf to reach the maximal mean arterial pressure (MAP) was highest in Group 3 among three groups. The relative maximal HR to the baseline value was similar in the three groups, but the relative maximal MAP to baseline value was significantly highest in the elderly patient group. The times to reach the maximal HR and BP were shortest in Group 1 among three groups. There were no significant differences in the CI between three groups. CONCLUSIONS: The inhalation of a high concentration of desflurane increases the HR, BP and CI transiently in all age groups. In pediatric patients, HR and BP increases more rapidly than in young adults and elderly patients. The relative maximal MAP to the baseline value is higher in elderly patients.

Spontaneous Intracranial Hypotension after Post-dural Puncture Headache : A case report / 대한마취과학회지

Spontaneous intracranial hypotension (SIH) occurs without any preceding events such as lumbar puncture, surgery, trauma, or medical illness. It is characterized by a postural headache that is aggravated whilst in the erect or sitting position, and is relieved in the supine position. A postural headache usually resolves either spontaneously or with conservative treatment. An epidural block is a very important treatment for lumbago and is mostly performed for pain control. However, an incidental dural puncture is possible during epidural block and anesthesiology and pain medicine doctor should be familiar with an epidural block. Radioisotope cisternography is a highly sensitive, reliable and safe technique for confirming of the presence and location of cerebrospinal fluid (CSF) leakage. We report two cases of spontaneous intracranial hypotension that was diagnosed by SIH through cisternography in a situation where the post-dural puncture headache was primarily suspected as being the cause. If a postural headache occurs after an epidural block through an epidural needle without CSF leakage, other causes e.g. dural puncture need to be identified.

Desflurane-induced Hemodynamic Changes in Patients with Hypertension / 대한마취과학회지

BACKGROUND: A rapid increase in the desflurane concentration induces tachycardia and hypertension and increases the plasma catecholamine concentration. This study compared the desflurane-induced hemodynamic responses in hypertensive patients with those of normotensive patients. METHODS: Sixty patients, 30 normotensive patient (group 1) and 30 hypertensive patients (group 2), were scheduled to undergo elective surgery under general anesthesia. The hypertensive patients have been taking regular antihypertensive drugs and their blood pressure and heart rate was well controlled. Thirty normotensive patients were not premedicated. The inspired concentration of desflurane through the mask was increased abruptly to 12.0 vol%. The target was to produce an end-tidal concentration of desflurane (ETdesf) of 10.0 vol% which was maintained until the end of the study by adjusting the vaporizer dial setting. The heart rate (HR), blood pressure (BP), cardiac index (CI), systemic vascular resistance (SVR), ETdesf, end-tidal concentration of carbon dioxide, and peripheral oxygen saturation were measured at the baseline and every 30 seconds for 5 minutes after inhaling of desflurane and for 2 minutes after intubation. RESULTS: The HR, BP, and CI increased significantly in the two groups compared with the baseline. However, the HR, blood pressure, CI, SVR, and ETdesf were similar in both groups. In addition, there were no significant differences of hemodynamic changes between the beta-blocker and the calcium channel blocker in the hypertensive patients. CONCLUSIONS: In patients with well-controlled hypertension, the hemodynamic responses to desflurane are similar to those in normotensive patients.

Comparison of Sevoflurane-N2O and Propofol-N2O Anesthesia for Laryngeal Microscopic Surgery / 대한마취과학회지

BACKGROUND: Laryngeal microscopic surgery is stressful as a result of the intubation and suspension laryngoscopy during the short operation time. Therefore, the objectives of the anesthesiologist are to maintain sufficient anesthetic depth, promote rapid awakening, and return the protective airway reflexes. This study compared the hemodynamic responses and recovery patterns between propofol-N2O and sevoflurane-N2O anesthesia. METHODS: Sixty outpatients undergoing laryngeal microscopic surgery were randomly divided into three groups: Endotracheal intubation with the effect-site concentration of propofol fixed at 3 ug/ml (Group P3), 4 ug/ml (Group P4) or endotracheal intubation with sevoflurane anesthesia (Group S). In all groups, the anesthesia was supplemented with up to 50% of N2O. The hemodynamic responses during intubation and suspension laryngoscopy were compared. In addition, extubation time, emergence time and the state of recovery (Steward score) were compared. RESULTS: After intubation and suspension laryngoscopy, the mean arterial pressure was significantly higher in Group S than in Groups P3 and P4 (P < 0.05). The heart rate was significantly higher in Group S than in the Group P4 (P < 0.05). The extubation times were not significantly different. However, the time for responding to a verbal command was significantly faster in Groups P3 (7.8 +/- 2.3 min) and P4 (8.8 +/- 1.9 min) than in Group S (10.6 +/- 1.8 min). The Steward score 1 min after extubation was significantly higher in Group S (P < 0.05). CONCLUSIONS: Propofol-N2O anesthesia can be useful in laryngeal microscopic surgery.

Optimal Dose of Ephedrine for Attenuation of Hemodynamic Changes during Propofol-Alfentanil Anesthesia / 대한마취과학회지

BACKGROUND: Propofol and alfentanil are frequently combined for general anesthesia. However, hypotension and bradycardia are common during anesthetic induction and maintenance. The purpose of this study was to compare the response of different doses of ephedrine to investigate an optimal dose of ephedrine for attenuation of the hemodynamic changes. METHODS: Eighty patients of ASA physical status 1 or 2 were assigned to one of four groups. Each patient received normal saline (E0), ephedrine 0.15 mg/kg (E15), 0.2 mg/kg (E20), 0.25 mg/kg (E25) after assessment of baseline hemodynamic values. If hemodynamic parameters are stabilized after intubation, baseline values were assessed by average during 3 minutes. Then each dose of ephedrine was given to each patient. The changes in systolic/diastolic blood pressure (SBP/DBP), mean arterial pressure (MAP), and heart rate (HR) were measured every one minute for 10 minutes. RESULTS: The use of ephedrine was effective for attenuation of the hemodynamic changes. E15, E20, and E25 showed statistical difference in BP and HR compared with E0. There was no statistical difference between E20, E25. Moderate hypertension (SBP 160-179 or DBP 100-109) is occurred each 4, 6 cases in E20, E25. CONCLUSIONS: All group of ephedrine injection resulted in elevation of BP, but did not caused HR change. Injection of ephedrine 0.2 mg/kg or 0.25 mg/kg led to excessive blood pressure elevation. Therefore, we consider more than 0.15 mg/kg of ephedrine is not necessary to minimize hemodynamic changes during propofol-alfentanil anesthesia.

The Effect of Nicardipine on Hemodynamic Responses to Tracheal Intubation during Inhalation with Sevoflurane / 대한마취과학회지

BACKGROUND: Laryngoscopy and tracheal intubation often provoke an undesirable increase in blood pressure and heart rate. Nicardipine-induced reduction in blood pressure was greater with inhalational anesthetics than nicardipine alone. This study was designed to determine the optimal dose of nicardipine for acceptable hemodnamic change during inhalation with sevoflurane. METHODS: Eighty ASA physical status 1 patients were randomly allocated into four groups of twenty patients. Tracheal intubation under direct laryngoscopy was performed. After intravenous thiopental 5 mg/kg, vecuronium 0.13 mg/kg 5, 10 or 15microgram/kg of nicardipine was given intravenously followed by mask ventilation of three minutes with sevoflurane, nitrous oxide and oxygen. Heart rate and blood pressure were measured at the period of baseline, preintubation, immediately after intubation, 1, 2, 4, 6 and 9 minutes following intubation. RESULTS: After tracheal intubation, the increase of systolic blood pressure was suppressed significantly by nicardipine 10 and 15microgram/kg group compared with the control group. The increase of heart rate was greatest in the nicardipine 15microgram/kg group. CONCLUSIONS: We suggest that the appropriate dose of nicardipine during induction with sevoflurane for attenuation of pressor responses to laryngoscopy and intubation in healthy patients is 10microgram/kg.

Acute Obstruction of an Endotracheal Tube Due to Large Mucous Plug: Removed Using Flexible Fiberoptic Bronchoscopy: A case report / 대한마취과학회지

An endotracheal tube obstruction causes serious complications, including cardiovascular instability, pneumothorax, pulmonary edema and brain death. A 74 year old woman was scheduled to undergo a laminectomy and instrument fixation due to tuberculosis spondylitis. The patient was intubated with a 7.0 mm reinforced endotracheal tube, and moved into the prone position. At 100 min after the initiation of anesthesia, signs of partial endotracheal obstruction were observed, including high airway pressure and low tidal volume. The signs of an airway obstruction were aggravated as the operation proceeded. Thirty minutes after the sign of a partial obstruction, those of a total endotracheal obstruction were observed. A mucoid impaction in the endotracheal tube was detected using flexible fiberoptic bronchoscopy. After removing this plug, the ventilation of the patient was maintained within normal limits.

Hydrothorax Detected at Postanesthetic Care Unit after Percutaneous Nephrolithotomy: A case report / 대한마취과학회지

Percutaneous nephrolithotomy (PCNL) is a well-established procedure for treating nearly all types of stones in the kidneys and middle-to-upper ureters. In addition, PCNL is less invasive, and provides safe results comparable to open surgery. However, there is risk of an increased risk of thoracic complications when performing a puncture above the 12 th rib to optimize kidney access. We experienced a 30-years-old female who had oxygen desaturation and complained dyspnea and chest pain at the postanesthetic care unit after percutaneous nephrolithotomy. Therefore, patients undergoing percutaneous renal manipulation need to be monitored for pulmonary complications during and after the procedure.

Comparison of Desflurane-induced Circulatory Responses by the Rate of Increase in Inhaled Desflurane Concentration / 대한마취과학회지

BACKGROUND: A rapid increase in desflurane concentration induces tachycardia and hypertension and increases plasma catecholamine concentration. No clinical study is available as to whether the desflurane-induced circulatory responses is blunted by the rate of increase in inhaled desflurane concentration although there were many studies about methods to blunt the circulatory responses. The current study examined to compare desflurane-induced circulatory responses by the rate of increase in inhaled desflurane concentration. METHODS: Unpremedicated sixty ASA physical status 1 patients, aged 20-60 years, scheduled for elective surgery under general anesthesia were randomly allocated into one of two groups. The inspired concentration of desflurane via mask was increased to 12.0 vol% abruptly (group 1), or during 120 seconds (group 2). The target was to produce an end-tidal concentration of desflurane (ETdesf) of 10.0 vol% which was maintained until the end of the study by adjusting the vaporizer setting, when necessary. Heart rate (HR), mean arterial pressure (MAP), cardiac index (CI), systemic vascular resistance (SVR), ETdesf, end-tidal concentration of carbon dioxide, and peripheral oxygen saturation were measured at baseline and every 30 seconds for 5 minutes after inhalation of desflurane and for 2 minutes after intubation. RESULTS: HR, blood pressure, and CI were significantly increased in two groups compared with baseline, but significant differences in maximum values were not observed between two groups. There were no significant differences between groups of the ETdesf at the maximal HR and MAP. Incidences of hypertension and tachycardia were lesser in slowly increased inhaled desflurane concentration (group 2) than abruptly increased group (group 1). CONCLUSIONS: The present study demonstrates that increasing inhaled desflurane concentration slowly for mask ventilation is partially effective in attenuating desflurane-induced circulatory responses.

Unexpected Pulmonary Edema Associated with an Intranasal Spray of Phenylephrine during the Induction of General Anesthesia: A case report / 대한마취과학회지

Topical phenylephrine is used in nasotracheal intubation to prevent nasal mucosal bleeding. The administration of topical phenylephrine can result in severe hypertension secondary to alpha-adrenergic stimulation. A high incidence of pulmonary edema is present in the patients given drugs with beta-blocking activity after phenylephrine administration. We report upon a pediatric patient in whom severe hypertension and pulmonary edema occured following the administration of topical phenylephrine.