MR evaluation of the anterior cruciate ligament: value of axial images.

Objective: To investigate the accuracy of diagnosing anterior cruciate ligament (ACL) tears with axial MR imaging.

Materials And Methods: Two blinded independent observers retrospectively reviewed axial T2 weighted or FSE fat suppressed imaging of the knee from 47 patients. Arthroscopy had demonstrated a complete tear of the ACL in 25 patients and a normal ACL in 22 patients.

Incidence of malignant hyperthermia reactions in 2,214 patients undergoing muscle biopsy.

To determine the incidence of malignant hyperthermia (MH) reactions after trigger-free anaesthesia in a large population of MH-susceptible (MHS) patients, the charts of 2,214 patients who underwent elective muscle biopsy for malignant hyperthermia were reviewed. Either general or regional anaesthesia with non-triggering drugs was used. For general anaesthesia, the trachea was intubated in the absence of muscle relaxants.

Clinical characteristics of sevoflurane in children. A comparison with halothane.

Background: For pediatric patients, sevoflurane may be an alternative to halothane, the anesthetic agent used most commonly for inhalational induction. The induction, maintenance, and emergence characteristics were studied in 120 unpremedicated children 1-12 yr of age randomly assigned to receive one of three anesthesia regimens: sevoflurane with oxygen (group S), sevoflurane with nitrous oxide and oxygen (group SN), or halothane with nitrous oxide and oxygen (group HN).

Methods: Anesthetic was administered (via a Mapleson D, F or Bain circuit) beginning with face mask application in incremental doses to deliver maximum inspired concentrations of 4.

A biomechanical comparison of Gardner-Wells tongs and halo device used for cervical spine traction.

Summary Of Background Data: Unstable cervical spine fractures and dislocations are often reduced by the application of axial traction using a halo or Gardner-Wells tongs. Failure of tong or halo attachment can cause substantial morbidity and usually occurs at the pin-bone interface. Institutions commonly clean and reuse tongs.

Proximate delivery of a large experimental dose from salbutamol MDI induces epithelial airway lesions in intubated rabbits.

The delivery of aerosolized drugs by metered dose inhaler (MDI) to intubated patients can be substantially improved by actuating the MDI through a narrow catheter placed inside the tracheal tube. However, the deposition of increased quantities of drug, surfactant, in particular oleic acid, and chlorofluorocarbon propellants on the lung surface could result in adverse effects not observed after oral MDI administration. To investigate this hypothesis, 42 adult intubated rabbits (six groups, n = 6 to 9/group) received Ventolin MDI, Ventolin placebo, a placebo MDI containing lecithin as surfactant, instilled salbutamol sulfate, instilled oleic acid solution, or no treatment (control).

The incidence of masseter muscle rigidity after succinylcholine in infants and children.

To determine whether the incidence of masseter muscle rigidity is affected by the anaesthetic induction sequence, we prospectively studied for ten months the anaesthetic course in 5,641 infants and children who received muscle relaxation to facilitate tracheal intubation. The anaesthetic induction sequence consisted of intravenous sodium thiopentone (STP) 5 mg.kg-1 alone, halothane induction alone 1-4%, or halothane followed by STP.

The pharmacology of sevoflurane in infants and children.

Background: Sevoflurane is a new volatile anesthetic with physical properties that should make it suitable for anesthesia (MAC of sevoflurane on oxygen alone and in 60% nitrous oxide, (MAC) of sevoflurane in oxygen alone and in 60% nitrous oxide, the hemodynamic, induction and emergence responses to sevoflurane and the metabolism to inorganic fluoride were studied in 90 ASA physical status 1 or 2 neonates, infants, and children.

Methods: MAC of sevoflurane in oxygen was determined in six groups of subjects stratified according to age: full-term neonates, infants 1-6 and > 6-12 months and children > 1-3, > 3-5 and > 5-12 yr. MAC in 60% nitrous oxide was determined in a separate group of children 1-3 yr of age.

Oral premedication for paediatric ambulatory anaesthesia: a comparison of midazolam and ketamine.

To compare the clinical characteristics of two oral premedicants, midazolam and ketamine, 40 healthy children, one to six years of age, who were scheduled for ambulatory dental surgery, were assigned to receive either oral midazolam 0.5 mg.kg-1 or oral ketamine 5.

The effect of adenosine-induced hypotension on systemic and splanchnic hemodynamics during halothane or sevoflurane anesthesia in the rat.

Background: It has been suggested that the liver may be at risk for ischemic damage during adenosine-induced hypotension. This notion, however, is somewhat inconsistent with the understanding that adenosine is a powerful vasodilator of the splanchnic circulation. To help clarify the effect of adenosine-induced hypotension on splanchnic hemodynamics, we studied the systemic and splanchnic hemodynamic responses to adenosine, both alone and in the presence of halothane or sevoflurane.

Oral midazolam premedication for children with congenital cyanotic heart disease undergoing cardiac surgery: a comparative study.

To determine whether oral midazolam is a safe and effective alternative to our current standard premedication for children with cyanotic congenital heart disease (CCHD), 30 children aged 1-6 yr, scheduled for elective cardiac surgery, were studied. The children were randomly assigned to one of two groups: Group I received oral midazolam 0.75 mg.

The effects of bone cement powder on human adherent monocytes/macrophages in vitro.

This study reports the effects of Simplex bone cement powder (BC) on the proliferation and production of bone resorbing factors in vitro by human adherent monocytes/macrophages. Adherent peripheral blood cells were isolated from seven healthy individuals and exposed to a dispersion of BC powder (1 mg/mL), phytohemagglutinin (PHA, 40 micrograms/mL), or medium alone at different periods of cell incubation (days 0-2, 0-7, 5-7, or 10-12). Cell proliferation was quantified by incorporation of 3H-thymidine uptake.

Oral midazolam premedication in children: the minimum time interval for separation from parents.

To determine the minimum time interval between oral midazolam (0.5 mg.kg-1) premedication and separation from parents that ensures a smooth separation, 30 children were assigned randomly to one of three groups (ten children per group).

Publication of abstracts presented at anaesthesia meetings.

To determine the publication rate of abstracts as peer-reviewed manuscripts during the five years subsequent to their presentation, the rates of publication of abstracts that were presented at meetings of four anaesthesia societies (American Society of Anesthesiologists (ASA), International Anesthesia Research Society (IARS), Anaesthesia Research Society (ARS) and Canadian Anaesthetists' Society (CAS), in 1985 were determined. Abstracts (total = 215) from each of the four meetings were selected (ASA n = 114/573 total, IARS n = 39/119, ARS n = 33/99 and CAS n = 29/58) and their appearances in the literature as peer-reviewed manuscripts were determined using MEDLINE for the years 1985 to 1990 under the surname of the presenting author. The contents of the abstracts were compared with those of the resultant manuscripts.

Are all preterm infants younger than 60 weeks postconceptual age at risk for postanesthetic apnea?

Background: Preterm and ex-preterm infants are at risk for life-threatening apnea after general anesthesia. The authors attempted to define the postconceptual age beyond which apnea is less likely to occur and to identify the factors that predispose to postanesthetic apnea.

Methods: Ninety-one infants younger than 60 weeks postconceptual age undergoing 101 general anesthetics were prospectively studied.

Dosing efficiency and particle-size characteristics of pressurized metered-dose inhaler aerosols in narrow catheters.

An experimental in vitro model was used to determine the effects of intraluminal catheter diameter and length on the delivered dose and particle-size characteristics of salbutamol (albuterol) aerosol delivered by metered dose inhaler (MDI) (Ventolin, 100 micrograms per puff). The dose of aerosolized drug that exited a 16-cm-long tracheal tube with an inner diameter (ID) of 6 mm was compared with that from 4 catheters of differing diameters and lengths that were inserted individually into the tracheal tube. The salbutamol MDI canister was actuated ten times into each delivery system, and the effluent aerosol was trapped onto a filter.

Hemodynamic and organ blood flow responses to halothane and sevoflurane anesthesia during spontaneous ventilation.

This study compared systemic hemodynamic and organ blood flow responses to equipotent concentrations of halothane and sevoflurane during spontaneous ventilation in the rat. The MAC values for halothane and sevoflurane were determined. Cardiac output and organ blood flows were measured using radiolabeled microspheres.

Premedication of children with oral midazolam.

In a randomized, double-blind, placebo-controlled study, the safety, efficacy and feasibility of oral midazolam premedication in children were evaluated in an ambulatory surgery unit. Eighty unmedicated children (ASA PS I or II, ages 1-6 yr) were randomly assigned to one of four groups receiving midazolam 0.5, 0.

Adequacy of caudal analgesia in children after penoscrotal and inguinal surgery using 0.5 or 1.0 ml.kg-1 bupivacaine 0.125%.

To determine the optimal volume of bupivacaine 0.125% for postoperative caudal analgesia, we compared the effectiveness of 0.5 ml.

Factors affecting the rate of disappearance of sevoflurane in Baralyme.

The effects of temperature, water and Baralyme exhaustion on the rate of disappearance of sevoflurane in Baralyme were studied in an in vitro model. We found that the rate of disappearance of sevoflurane in Baralyme increased as the temperature increased and decreased as the concentration of water increased. The disappearance of sevoflurane also decreased in the presence of exhausted Baralyme compared with fresh Baralyme.

Haemodynamic and organ blood flow responses to sevoflurane during spontaneous ventilation in the rat: a dose-response study.

To determine the systemic haemodynamic and organ blood flow responses to the administration of sevoflurane during spontaneous ventilation, heart rate, cardiac index, mean arterial pressure, arterial blood gases, and blood flows to the brain, spinal cord, heart, kidneys and splanchnic organs were measured awake (control values) and after 30 min of anaesthesia with 0.5, 1.0, 1.