S. K. Min

Carbon dioxide and argon gas embolism during laparoscopic hepatic resection.

During laparoscopic hepatic resection, an abrupt decrease in FE’CO2 (from 28 mmHg to 9 mmHg) associated with near cardiac arrest occurred concomitantly with hepatic vein laceration and the use of an argon beam coagulator system. During venous gas embolism, transesophageal echocardiography (TEE) proved the transpulmonary passage of the gas. In the post‐operative period, the patient developed pulmonary edema and made a full recovery after 5 days. This is a case report of a possible paradoxic carbon dioxide (CO2) and argon gas embolism by transpulmonary passage during laparoscopic hepatic resection.

The optimal dose of remifentanil for intubation during sevoflurane induction without neuromuscular blockade in children

The optimal dose of remifentanil needed to produce successful intubating conditions following inhalation induction of anaesthesia using 5% sevoflurane without the use of neuromuscular blocking drugs, was investigated in 25 children aged 3–10 years. Sixty seconds after inhalation induction of anaesthesia using sevoflurane 5% in 100% oxygen, a predetermined dose of remifentanil was injected over 30 s. The dose of remifentanil was determined using the modified Dixons up‐and‐down method (0.2 μg.kg−1 as a step size). The first patient was tested at 1.0 μg.kg−1 remifentanil. Ninety seconds following the bolus administration of remifentanil, the childs trachea was intubated. The optimal bolus dose of remifentanil required for successful tracheal intubation was 0.56 (0.15) μg.kg−1 in 50% of children during inhalation induction using 5% sevoflurane in the absence of neuromuscular blocking drugs. Using probit analysis, the 95% effective dose (ED95) of remifentanil was 0.75 μg.kg−1 (95% confidence limits 0.63–1.38 μg.kg−1).

Anaesthesia in patients with Brugada syndrome

Brugada syndrome is characterized by right bundle branch block, ST segment elevation in the precordial leads and sudden death caused by ventricular fibrillation. We present two successful anaesthetic management cases in patients with Brugada syndrome.

The median effective dose of dexmedetomidine for laryngeal mask airway insertion with propofol 2.0 mg/kg

Dexmedetomidine can be used as a co‐induction agent to facilitate laryngeal mask airway (LMA) insertion with minimal effect on respiratory function. The purpose of the study was to determine the median effective dose (ED50) of dexmedetomidine to facilitate LMA insertion during anaesthesia induction with propofol 2.0 mg/kg without neuromuscular blockade.

Effect-site concentration of remifentanil for nasotracheal versus orotracheal intubation during target-controlled infusion of propofol.

The concentration of remifentanil required for acceptable nasotracheal intubation in adults after target-controlled infusion (TCI) of propofol without neuromuscular blockade was compared with that required for orotracheal intubation. Twenty-five patients undergoing oral and maxillofacial surgery received nasotracheal intubation and 25 undergoing ear, nose and throat surgery received orotracheal intubation. Anaesthesia was induced with propofol TCI at a target effect-site concentration of 5.0 μg/ml. The 50% and 95% effective concentrations (EC50 and EC95, respectively) for remifentanil, calculated using isotonic regression, were 5.40 and 6.85 ng/ml, respectively, in the orotracheal group and 5.75 and 7.43 ng/ml in the nasotracheal group. The EC50 (± SD) values for remifentanil, calculated using a modified Dixons up-and-down method, were 6.08 ± 0.75 and 5.58 ± 0.75 ng/ml for nasotracheal and orotracheal intubation, respectively. Effect-site remifentanil concentrations did not differ significantly between the two groups of patients. Coadministration of propofol and remifentanil can provide acceptable conditions for nasotracheal intubation without neuromuscular blockade.

Effect‐site concentration of propofol for reduction of remifentanil‐induced cough

This study examined the effectiveness of different propofol infusion target concentrations on cough suppression, during a target‐controlled remifentanil infusion. Four hundred patients were randomly assigned to receive propofol target effect‐site concentrations of 0, 3.0, 4.5, or 6.0 μg.ml−1. When the propofol effect‐site concentration reached the target, remifentanil was administered at a target effect‐site concentration of 4.0 ng.ml−1. Episodes of cough were recorded over a 2‐min period after remifentanil commencement, and graded as mild (1–2), moderate (3–4), or severe (5 or more). The overall incidence of cough was significantly decreased in by propofol 6.0 μg.ml−1 compared with 0 or 3.0 μg.ml−1 propofol (p < 0.001). The incidence of severe cough was significantly lower with propofol 6.0 μg.ml−1 compared with 3.0 μg.ml−1 (p = 0.03). A propofol target effect‐site concentration of 6.0 μg.ml−1 effectively suppressed remifentanil‐induced cough when remifentanil was administrated at a target effect‐site concentration of 4.0 ng.ml−1.

Limited maximal flow rate of target-controlled remifentanil infusion and induced cough.

This study evaluated the effect of limiting maximal infusion‐pump flow rate on suppression of remifentanil‐induced cough during target‐controlled infusion. Two hundred and ten patients were randomly assigned to receive remifentanil at an effect‐site concentration of 4.0 ng.ml−1 with maximal flow rate limited to 100 (group R100), 200 (group R200), or 1200 ml.h−1 (group R1200). The number of episodes of cough were recorded and graded as mild (1–2), moderate (3–4), or severe (5 or more). The incidence of cough was 2.9% in group R100, 5.7% in group R200 and 25.7% in group R1200. Patients in group R100 and R200 had a significantly lower incidence of cough than those in group R1200 (p < 0.05). Zero, two and five patients coughed a moderate amount in groups R100, R200 and group R1200, respectively (p < 0.05). Limiting maximal infusion rate during remifentanil TCI suppressed remifentanil‐induced cough.

Awake nasotracheal intubation using fiberoptic bronchoscope in a pediatric patient with Freeman-Sheldon syndrome.

The Freeman–Sheldon syndrome is a congenital disease primarily affecting the facial, limb and respiratory muscles that give rise to classical clinical features including typical whistling face and short webbed neck associated with difficult intubation. We present successful awake nasotracheal intubation in a 6‐year‐old patient with typical clinical features of Freeman–Sheldon syndrome by using fiberoptic bronchoscope on two separate occasions.

Bolus effective dose of ketamine for preventing withdrawal movement on injection of rocuronium in paediatric patients.

The bolus effective dose of ketamine required to prevent withdrawal movement on injection of rocuronium was determined in 27 paediatric patients undergoing elective surgery. A predetermined dose of ketamine was given intravenously on arrival in the operating room and anaesthesia (2.5% thiopental, 5 mg/kg) was administered 1 min later. After loss of consciousness, 1% rocuronium at 0.6 mg/kg was injected over 5 s and the presence or absence of withdrawal movement recorded. The effective dose of ketamine was determined using a modified Dixon up-and-down method with a step size of 0.1 mg/kg, successful prevention of withdrawal movement being defined as no response or movement at the wrist only. The bolus effective dose of ketamine for preventing withdrawal movement after injection of rocuronium following thiopental anaesthesia in 50% of paediatric patients (ED50) was 0.21 mg/kg according to the modified Dixon up-and-down method. Probit analysis indicated an ED50 of 0.18 mg/kg and an ED95 of 0.33 mg/kg. The latter was the most satisfactory dose in the clinical setting.

The anesthetic management of a venous bullet embolism to the right ventricle − A case report −

Bullet embolism is a rare complication of non-penetrating gunshot trauma. There are two types of bullet embolisms: arterial and venous. Accurate preoperative localization of the bullet is important for selecting the proper surgical and anesthetic techniques. We report here on a rare case of venous bullet embolus to the right ventricle from the right iliac vein, as was demonstrated by transesophageal echocardiography.