[Effectiveness of Sacral Intervertebral Epidural Block for Umbilical Hernia Repair in Children].

BACKGROUND: Effectiveness of sacral intervertebral epidural block (S 2-3 block) for umbilical hernia repair has not been clarified. METHOD: We investigate 24 children, undergoing umbilical hernia repair; mean age of 3 years (age range: 20-65 months). Under general anesthesia, epidural block was performed at S 2-3 interspace with 1 ml x kg(-1) ropivacaine (0.2%) at injecting rate of 1 ml x sec(-1) followed by 0.25 ml x kg(-1) normal saline. RESULTS: In all cases, neither systolic blood pressure nor heart rate increased > 15% from those just before the block. Postoperative analgesics were given in 6 patients (25%) rectally. Mean time between the block and the administration of analgesic was 10.5 hours. CONCLUSIONS: S 2-3 block can be effective for postoperative pain in umbilical hernia repair.

[The use of dexmedetomidine and Airwayscope in airway management of a child with Cornelia de Lange syndrome].

We report anesthetic management of a 22-month-old child with Cornelia de Lange syndrome scheduled for palatoplasty because of cleft palate. Micrognathia and short neck of the patient suggested difficult airway management. For anesthetic induction, 1 microg x kg(-1) dexmedetomidine was loaded intravenously, followed by infusion at a rate of 0.7 microg x kg(-1) x hr(-1) with incremental inhalation of sevoflurane. During the induction, spontaneous breathing was maintained. By laryngoscopy with Machintosh blade after intravenous propofol for the purpose of laryngeal reflex inhibition, only the tip of epiglottis was seen. Then, after another intravenous propofol, laryngoscopy was performed with Airwayscope, which enabled operators to see the glottis. Then, a RAE endotracheal tube (ID 4.5 mm) was inserted. During the Airwayscope operation, pharyngeal reflex, laryngeal reflex and saliva increase were inhibited resulting in good view of the larynx and the lowest Spo2 was 94% temporarily. After intubation, anesthesia was maintained with sevoflurane, remifentanil and fentanyl. Dexmedetomidine infusion was also useful to maintain adequate spontaneous breathing and to achieve awaking before extubation.

[Assessment of intraoperative hemodynamics, infusion volume, urinary output and dose of circulatory drugs in general anesthesia with transversus abdominis plane block for cholecystectomy].

We retrospectively reviewed intraoperative hemodynamics, infusion volume, urinary output and dose of circulatory drugs in patients undergoing cholecystectomy in 3 types of anesthesia group: General anesthesia (GA group), general anesthesia with epidural anesthesia (EPI group) and general anesthesia with transversus abdominis plane (TAP) block (TAPB group). TAP block was performed using ultrasound-guided subcostal method and 20-30 ml of ropivacaine (0.2-0.3%) was injected to TAP bilaterally. Though, the blood pressure in TAPB group was lower than that in GA group, the degree of low blood pressure was smaller than that in EPI group. Less changes in intraoperative blood pressure, infusion volume and dose of phenylephrine in TAPB group compared to those in EPI group can be the advantage of TAP block alternative to epidural anesthesia.

[Anesthetic management of an emergency open-heart surgery for entrapment of a circular mapping catheter by chordae tendineae with mitral valve damage undergoing atrial fibrillation ablation].

The entrapment of a circular mapping catheter by chordae tendineae during catheter ablation is a very rare but serious complication requiring, in some cases, surgical treatment. We report a case that required open heart surgery for catheter removal and mitral valve repair. A 79-year-old man underwent catheter ablation for paroxysmal atrial fibrillation in other hospital. During the operation, he moved accidentally, despite circular mapping catheter was in the left atrium. The circular mapping catheter was uncontrolable due to resistance interfering with catheter removal, and the patient was brought to our hospital for open heart surgery to remove catheter. General anesthesia was induced and maintained with midazolam, fentanyl. Transesophageal echocardiography was performed to monitor catheter position and mitral valve condition. Transesophageal echocardiography revealed that circular catheter tip was located adjacent to the posterior mitral leaflet and the presence of moderate mitral valve regurgitation. Circular catheter tip was entraped by chordae tendineae and caused posterior mitral leaflet damage. Intracardiac foreign body removal and posterior mitral leaflet repair were completed uneventfully under cardiopulmonary bypass. The postoperative course was uneventful. It is expected that catheter ablation for atrial fibrillation will increase in number. This rare complication of catheter ablation may become a threat to cardiologist, cardiac surgeon and anesthesiologist.

[A case of severe hypotension caused by external cardiac compression by tumor and doctor's hand in a patient with mediastinal tumor].

There are several causes of hypotension during anesthesia. We report a case of severe hypotension caused by external cardiac compression. A 72-year-old man was scheduled for resection of mediastinal tumor under general anesthesia. He had undergone mediastinal tumor resection four times uneventfully. Anesthesia was induced and maintained with target controlled infusion of propofol and continuous infusion of remifentanil. Tracheal intubation was facilitated with rocuronium. Massive bleeding and severe hypotension developed during the operation. Blood transfusion, cryoprecipitate, fresh frozen plasma, and percutaneous cardiopulmonary support were commenced. However, hemorrhage was not the only cause of hypotension. The transesophageal echocardiography revealed external cardiac compression by tumor and doctor's hand. Transesophageal echocardiography was useful for verifying the causes of hypotension. It is necessary to evaluate the causes of hypotension during the operation, because a certain number of problems may exist.

[General anesthesia for a boy with Wolf-Hirschhorn syndrome].

Wolf-Hirschhorn syndrome (WHS) is a rare chromosomal abnormality in which there is deletion of the short arm of chromosome no. 4. Features of the condition include severe psychomotor retardation, characteristic facies and various congenital midline fusion anomalies. We report the anesthetic management in a 6-year-old boy with WHS, scheduled for renal biopsy under general anesthesia. Anesthesia was induced and maintained with sevoflurane and nitrous oxide in oxygen. Mask ventilation was performed easily. After establishment of mask ventilation, laryngeal mask airway (LMA) was inserted smoothly without muscle relaxant and an adequate airway was established with a LMA. He has episodes of transient deterioration in renal function with physical stress. To decrease renal effects of perioperative stress, transversus abdominis plane (TAP) block and intravenous patient controlled analgesia (IV-PCA) were administered for postoperative analgesia. The operation ended without any complications. Anesthetic emergence was rapid and he had no pain and decline in renal function.

[Anesthetic hazards in an undiagnosed case of retroperitoneal paraganglioma].

We report a patient with undiagnosed retroperitoneal paraganglioma who developed an intraoperative hypertensive crisis. A 64-year-old female was scheduled for right partial mastectomy and removal of an abdominal mass, preoperatively diagnosed as a small intestine GIST. Surgery was performed under general anesthesia combined with epidural anesthesia with close monitoring. Immediately after the surgical manipulation of the abdominal mass, her systolic blood pressure rose to over 200 mmHg. This hypertensive crisis was managed with nicardipine and alprostadil combined with increased infusion rate of remifentanil and propofol. Thereafter, the patient was hemodynamically stable and the postoperative course was uneventful. Pathological examination identified the tumor as extraadrenal paraganglioma. The possibility of paraganglioma should be considered even in asymptomatic abdominal mass, and adequate precautions are required in such cases.

[Low doses of ketamine have no effect on bispectral index during stable propofol-remifentanil anesthesia].

BACKGROUND: Ketamine is associated with an increase in the bispectral index (BIS) values that can lead to an overdose of hypnotic agents. We investigated the effect of ketamine on BIS values during general anesthesia with a target-controlled infusion (TCI) of propofol and infusion of remifentanil. METHODS: Forty-five ASA I or II patients undergoing gynecological surgery were included in this study. After 5 min of steady-state anesthesia (BIS at 35-45) without surgical stimulation, patients received either a bolus administration of ketamine 0.2 mg x kg(-1) (LK group) or ketamine 0.5 mg x kg(-1) (HK group). Patients in the control group received no intervention. BIS values were recorded every minute until 15 min after ketamine administration. RESULTS: After ketamine administration, BIS value in HK group increased significantly compared with that at baseline. There were no significant changes for BIS values in LK group and control group over time. BIS values in HK group were significantly higher than those in the LK group and control group after ketamine injection. BIS values were not statistically different between LK group and control group. CONCLUSIONS: Under stable propofol and remifentanil anesthesia, a small dose of ketamine did not increase the BIS value over the next 15 min.

[Esophageal injury after insertion of a transesophageal echocardiography probe in a patient with an aberrant right subclavian artery].

We describe a case of an esophageal injury caused by insertion of a transesophageal cardiac echo probe in a 66-year-old man with an aberrant right subclavian artery, who was scheduled for Bentall surgery for aortic regurgitation and annuloaortic ectasia. Preoperative CT scan showed an aberrant right subclavian artery compressed from the back of the esophagus. General anesthesia was induced with midazolam and fentanyl, and maintained with midazolam, remifentanil and fentanyl. After induction of anesthesia, a transesophageal cardiac echo probe was inserted without abnormal resistance. The operation was performed uneventfully. On the second day after surgery, gastrointestinal bleeding was suspected and the upper gastrointestinal endoscopy (GIF) was performed. GIF revealed ulceration at the mid-esophagus and gastroesophageal junction, and a large amount of fresh blood in the stomach. The location of the ulcer at mid-esophagus was likely to be over the aberrant right subclavian artery. Ulcers were treated conservatively. GIF on the postoperative day 16 revealed that ulcers had healed. Transesophageal echo probe insertion is potentially hazardous in a patient with an aberrant right subclavian artery. Although aberrant right subclavian artery is rare, transesophageal echocardiography should be performed with extreme caution.

Influence of skin thickness on the in vitro permeabilities of drugs through Sprague-Dawley rat or Yucatan micropig skin.

The purpose of this study was to clarify the influence of skin thickness on the in vitro permeabilities of 3 model drugs with different physicochemical properties (nicorandil (NR), isosorbide dinitrate (ISDN) and flurbiprofen (FP)) through Sprague-Dawley rat (rat) or Yucatan micropig (YMP) skin. Intact, dermis-split, stratum corneum-stripped or stratum corneum-stripped and dermis-split rat or YMP skin (rat skin thickness: approximately 0.4, 0.9 or 1.2 mm; YMP skin thickness: approximately 0.4, 0.9, 1.8 or 2.8 mm) were set in Franz-type diffusion cells to determine the permeation rate, lag time and resistance ratio of the viable epidermis and dermis against whole skin (R(ved)/R(tot)) of the drugs. The YMP skin permeabilities of the drugs decreased with an increase in the skin thickness, and significant differences were observed in the permeation rates and lag times between intact and dermis-split (0.4 mm) YMP skins. The decreases in the permeabilities of the drugs through the YMP skin were larger than those through the rat skin. The influence of resistances of ISDN and FP through the dermis-split rat or YMP skin was greater at 0.9 mm skin thickness than 0.4 mm skin thickness. The R(ved)/R(tot) values for the YMP skins were relatively large for lipophilic drugs (ISDN and FP), and these ratios increased with an increase in the dermis thickness. These results suggest that in vitro skin permeation studies must be done using dermis-split (0.4 mm) skin with the thinnest dermis for predicting in vivo human percutaneous absorption rate.

Usefulness of rat skin as a substitute for human skin in the in vitro skin permeation study.

Sprague-Dawley (SD) rats are broadly used in preclinical studies for drug development, so a lot of information for the rats can be obtained especially from pharmacokinetic, pharmacological and toxicological studies. The purpose of this study was to clarify whether SD rat skin can be used to predict human skin permeability. In vitro permeation studies of the three model drugs, nicorandil, isosorbide dinitrate, and flurbiprofen, through human skin and SD rat skin were performed using Franz-type diffusion cells. The permeation rates of the three model drugs through human skin and SD rat skin were determined, and their variations were evaluated. The inter-individual variations in SD rat skin permeability of the three model drugs were much lower than that in human skin permeability, although the permeation rates of the three model drugs through the SD rat skin were about twice those through human skin. In addition, no difference in the skin permeability coefficients of the three model drugs was obtained between fresh SD rat skin and frozen SD rat skin. The markedly smaller variation in the permeability through SD rat skin compared with that through human skin indicated that in vitro permeation studies using SD rat skin would be especially useful for evaluating differences in the skin permeability of the three model drugs as well as for predicting human skin permeability.

Variation assessment for in vitro permeabilities through Yucatan micropig skin.

The purpose of this study was to evaluate the variations in the in vitro Yucatan micropig (YMP) skin permeabilities of drugs and to clarify whether YMP skin can be used to predict human skin permeability. In vitro permeation studies of the three model drugs, nicorandil, isosorbide dinitrate and flurbiprofen, through YMP skin were performed using Franz-type diffusion cells. The permeation rates of the three model drugs were determined, and their variations were evaluated. The inter-individual variations in YMP skin permeability for the three model drugs were smaller than that in human skin permeability, and the permeation rates of the three model drugs through the YMP skin were approximately half that through human skin. In addition, the intra-individual variations in YMP skin permeability for nicorandil and flurbiprofen were much smaller than the inter-individual variations in YMP skin. The inter- and intra-regional variations in YMP skin permeability were very small. The markedly smaller variation in the permeability through YMP skin as compared with that through human skin indicated that in vitro permeation studies using YMP skin would be particularly useful for evaluating differences in the skin permeability of the three model drugs as well as for predicting human skin permeability.

[Spinal anesthesia for a inguinal hernia repair in a small child with laryngeal stenosis].

We experienced spinal anesthesia for inguinal hernia repair in combination with general anesthesia in a 4-year-old child with functional laryngeal stenosis and tendency of laryngeal edema. His airway was managed without endotracheal tube or laryngeal mask airway because these devices could worsen the upper airway stenosis. Spinal anesthesia offered reliable and potent analgesia leading to safe anesthetic management under spontaneous breathing. Although spinal anesthesia in combination with general anesthesia is not common in pediatric patients, it is effective and safe to apply for a case requiring more reliable and potent analgesia with understanding anatomical and physiological characteristics in children.

[Endotracheal tube selection in children: which is the better predictor for the selection, tracheal internal diameter in X-ray photograph or age-based formula?].

BACKGROUND: Age-based formula has been widely used to predict the appropriate size of the endotracheal tube in children. Tracheal internal diameter in X-ray photograph is reported to show higher correlation with a correct tube than age. In our institution, X-ray photographs were stored as digital images, enabling us to measure tracheal internal diameters more accurately than conventional X-ray films. Therefore, we investigated whether tracheal size in digital X-ray photograph is a better predictor for the tube selection than age. METHODS: We reviewed data from children aged 1 to 8 years for the past 5 years. The data included age, tracheal internal diameter at 6th cervical (C6), 2nd thoracic vertebrae (T2) in X-ray photograph and selected tube size. The tube size was estimated by the age-based formula or on the basis of tracheal size. RESULTS: The endotracheal tube size correlated significantly with the age, and tracheal internal diameter at C6 or T2 in X-ray photograph (correlation coefficients P=0.898, 0.653, and 0.771 respectively; P<0.0001). The tube size predicted by the age allowed appropriate intubation in 62.2%, but that by the tracheal size at C6 and T2 in 42.8% and 43.7% respectively. CONCLUSIONS: The age-based formula is more reliable and appropriate to decide the size of endotracheal tube for children than the tracheal size.

The effective time and concentration of nitrous oxide to reduce venipuncture pain in children.

STUDY OBJECTIVE: To investigate the time of administration and concentration of inhaled nitrous oxide (N(2)O) needed to reduce the pain associated with intravenous (i.v.) cannulation in children. DESIGN: Prospective, randomized study. SETTING: Operating room of a children's hospital. PATIENTS: 73 ASA physical status I and II children, aged 6-15 years, scheduled for elective day or non-day surgery. INTERVENTIONS: Children were randomly allocated to one of 4 groups prior to i.v. insertion of a 24-gauge catheter in the dorsum of the hand: Group 1 (n = 18): 50% N(2)O in O(2) for three minutes; Group 2 (n = 18): 50% N(2)O in O(2) for 5 minutes; Group 3 (n = 18): 70% N(2)O in O(2) for three minutes; or Group 4 (n = 19): 70% N(2)O in O(2) for 5 minutes. MEASUREMENTS: Just after the venous cannulation, degree of pain was assessed by examining the faces of the patient by the parent and an operating room nurse. MAIN RESULTS: Pain scores obtained from parents of children in Groups 3 and 4 were significantly lower than from those in Groups 1 and 2. Pain scores from the nurse in Group 3 was significantly lower than those in Group 1. However, there was no significant difference in pain score between Group 3 and Group 4. Frequency of side effects was similar among the 4 groups. CONCLUSIONS: Seventy percent N(2)O in O(2) given for three minutes was effective for reducing venipuncture pain in children.

[Prevention of postoperative nausea and vomiting by metoclopramide combined with dexamethasone in gynecological surgery].

BACKGROUND: The authors evaluated the efficacy of a combination of dexamethasone and metoclopramide for the prophylaxis of postoperative nausea and vomiting (PONV) after gynecological abdominal surgery. METHODS: One-hundred and seventeen patients scheduled for gynecological abdominal surgery were analyzed retrospectively. Patients were classified into three groups by anti-emetics administered; none (Group C, n = 38); metoclopramide 10 mg (Group M, n = 39); or a combination of metoclopramide 10 mg with dexamethasone 8 mg (Group MD, n = 40) at 30 to 60 minutes prior to the end of surgery. Anesthesia was induced by propofol and maintained with isoflurane-nitrous oxide inhalation and intermittent administration of fentanyl. Postoperative pain was treated with continuous subcutaneous infusion of pentazocine via a patient controlled analgesia device. PONV was assessed using a 5 rating verbal score in early (0-6 hr) and in late (6-24 hr) period. RESULTS: The 3 groups were similar in demographic characteristics. The incidence of nausea and vomiting in early period was significantly lower in Group MD compared with Group C and Group M. Rescue anti-emetic requirements were fewer in Group MD compared with Group C. There are no severe complications. CONCLUSIONS: A combination of metoclopramide and dexamethasone was more effective in preventing PONV compared with metoclopramide alone.

[Postoperative nausea and vomiting after laparoscopic cholecystectomy under total intravenous anesthesia using propofol combined with fentanyl or pentazocine].

BACKGROUND: The aim of this study was to compare the incidence of postoperative nausea and vomiting (PONV) in propofol-anesthetized patients receiving either fentanyl or pentazocine as opioid supplement. METHODS: Sixty-seven patients scheduled for laparoscopic cholecystectomy were analyzed retrospectively. Patients were classified into two groups according to opioid supplement under propofol-anesthesia; pentazocine group (n = 26) and fentanyl group (n = 41). Anesthesia was induced with propofol using target controlled infusion method, and was maintained with propofol infusion with pentazocine or fentanyl and intermittent administration of vecuronium with 40% oxygen in air. RESULTS: The incidence of PONV was 23.1% in fentanyl group and 22.0% in pentazocine group, respectively. The incidence of PONV was not different between the groups. There were no severe complications. CONCLUSIONS: The incidence of PONV in propofol-anesthetized patients receiving pentazocine as opioid supplement is not different from that in patients receiving fentanyl.

[Anesthetic managements for emergency cesarean section and craniotomy in patients with intracranial hemorrhage due to ruptured cerebral aneurysm and arteriovenous malformation].

We report two cases of anesthetic management for emergency cesarean sections and craniotomies in patients with intracranial hemorrhage. Case 1: A 32-year-old woman at 33 weeks gestation suffered from subarchnoid hemorrhage due to the rupture of cerebral aneurysm. Case 2: A 38-week-pregnant woman aged 32 developed intracerebral hematoma resulting from ruptured arteriovenous malformation. The weights of the fetuses were estimated to be 1756 g and 1996 g respectively, and they were expected premature. Discussions with obstetricians, neurosurgeons and neonatologists encouraged us to schedule cesarean section followed by craniotomy under general anesthesia. Before deliveries we selected isoflurane and avoided excessive hyperventilation to maintain uteroplacental circulation. After deliveries, isoflurane was changed to propofol and prostaglandin E1 was infused to control blood pressure and to avoid uterine atonic bleeding. Uneventful anesthetic course resulted in both the mothers and the fetuses surviving. It is important to develop good relationships among the specialists for the management of pregnant woman with intracranial hemorrhage.

[Dose requirements of pentazocine during abdominal surgery in total intravenous anesthesia using propofol].

BACKGROUND: To determine the dose requirements of pentazocine when administered as a single bolus dose in total intravenous anesthesia with propofol for abdominal surgery. METHODS: One hundred and fifty-six patients scheduled for abdominal surgery were analyzed retrospectively. Patients were classified into three groups according to duration of the operation ; under 120 min (Group 1, n=87) ; 120-240 min (Group 2, n=56) ; over 240 min (Group 3, n=13). Anesthesia was induced with propofol using target controlled infusion method, and was maintained with propofol infusion, pentazocine as a single dose before incision, and intermittent administration of vecuronium with 40% oxygen in air. RESULTS: Dosage of pentazocine was significantly increased according to length of the operation. The maintenance doses of propofol were not different among the three groups. Awakening time in about 80% of patients in each group was within 15 minutes. There are no severe complications. CONCLUSIONS: Total intravenous anesthesia with propofol and pentazocine is useful to stabilize hemodynamics and to achieve rapid recovery. For the operation within 120 min, 0.7 mg x kg(-1) of pentazocine is necessary whereas 0.8 mg x kg(-1) of pentazocine is needed in the operation of 120-240 min.

Clonidine-ephedrine combination reduces pain on injection of propofol and blunts hemodynamic stress responses during the induction sequence.

STUDY OBJECTIVES: To evaluate the effects of clonidine and ephedrine on propofol-induced pain and on hemodynamic changes during the induction sequence. DESIGN: This was a prospective, randomized, double-blind study. SETTING: The study was conducted at a university hospital. PATIENTS: 200 ASA physical status I or II adult patients scheduled for elective surgery. INTERVENTIONS: Patients were randomly allocated to one of 4 groups (50 patients per group): clonidine-ephedrine (CE), clonidine-saline (CS), diazepam-ephedrine (DE), and diazepam-saline (DS). Thirty seconds after the administration of ephedrine or saline, propofol 2 mg/kg was infused at a rate of 18.3 mL/min. MEASUREMENTS: Patients were asked whether they had pain due to propofol injection. A blinded investigator evaluated the pain score: 0 = no pain, 1 = mild pain, 2 = severe pain without behavioral signs such as grimace or arm withdrawal movement, and 3 = severe pain accompanied by behavioral signs. Mean arterial blood pressure (MAP) and heart rate (HR) were measured at 1-minute intervals from just before the administration of ephedrine or saline to 5 minutes after the tracheal intubation. MAIN RESULTS: Median pain score in CE was significantly lower than those in the other groups (P < 0.0001). Pain scores in CS and DE were significantly lower than that in DS (P < 0.05). Ephedrine increased HR in CE and DE (P < 0.05), but clonidine did not augment the effect. Mean arterial blood pressure before tracheal intubation decreased to comparable values in all groups. After the intubation, mean arterial blood pressure and HR in CE and CS were significantly lower than those in DE and DS (P < 0.05). CONCLUSIONS: Combination of clonidine and ephedrine effectively reduced propofol-induced pain, but did not prevent propofol-induced hypotension. Clonidine did not augment low dose of ephedrine-induced increase in HR and produced stable hemodynamic condition during the induction sequence.