Combined spinal epidural vs epidural labour analgesia: does initial intrathecal analgesia reduce the subsequent minimum local analgesic concentration of epidural bupivacaine?

Labour analgesia initiated using a combined spinal-epidural (CSE) technique may reduce subsequent epidural bupivacaine requirements compared with an epidural-only technique. We compared the minimum local analgesic concentrations (MLAC) of epidural bupivacaine following initial intrathecal or epidural injection. In a prospective, double-blind study, 115 women requesting epidural analgesia were randomly assigned to receive either an epidural with bupivacaine 20 mg and fentanyl 40 µg or a CSE with intrathecal bupivacaine 2.5 mg and fentanyl 5 µg. Analgesia was assessed using a visual analogue pain score. When further analgesia was requested, bupivacaine 20 ml was given, and the concentration was determined using the technique of up-down sequential allocation. The MLAC of bupivacaine in the epidural group was 0.032% wt/vol (95% CI 0.020-0.044) compared with 0.047% wt/vol (95% CI 0.042-0.052) in the CSE group. Bupivacaine requirements for the second injection were increased following intrathecal analgesia by a factor of 1.45 (p = 0.026) compared with epidural analgesia.

Effects of hemimandibulectomy on quality of life.

OBJECTIVE: To assess the quality of life and functional status of patients who have undergone hemimandibulectomy based on the type of reconstructive procedure performed. STUDY DESIGN: Survey, retrospective. METHODS: Twenty-one patients who had undergone hemimandibulectomy and had similar defects were divided into two groups based on the reconstructive technique utilized. Eleven patients were placed in the soft tissue reconstruction group. Ten patients were placed in the mandible reconstruction group. All patients were assessed for: function, utilizing the Performance Status Scale, and quality of life, using a general cancer questionnaire (FACT-G) and a series of questions specific for head and neck cancer patients. RESULTS: Mandible reconstruction produced a perceived better physical appearance (P = .02), better eating ability (P = .04), and a better overall quality of life (P = .002). The mandible reconstruction cohort consistently outscored the soft tissue cohort on all questionnaires. CONCLUSION: Restoration of mandibular continuity after hemimandibulectomy leads to improved function and a superior quality of life in appropriately selected patients.

Feed intake, weaning weight and net returns comparisons for four breeding systems.

Feed intake, weaning weight and direct and maternal contributions to weaning weight were estimated for four breeding systems using data collected between 1979 and 1986 from 773 cow-calf pairs at the Elora Beef Research Centre. Breeding systems included purebred Hereford (HE), small rotational dual purpose (SR) (a four-way rotational crossing system utilizing Tarentaise, Angus, Gelbvieh and Pinzgauer breeds), large rotational beef (LR) (composed of Maine-Anjou, Simmental and Charolais) and Angus-sired large rotational beef (AL) utilizing Angus as the sire breed and LR as the maternal breed. Large rotational dams had the highest feed intakes for both dry (8.9 kg DM/d) and lactation (11.5 kg DM/d) periods. Conversely, HE calves consumed the greatest amounts of creep feed (309 kg DM), followed by AL, SR and LR. The large rotational system had the highest weaning weights (265 kg) and direct (12.3 kg greater than average of observations) and maternal (9.6 kg greater than average of observations) contributions to weaning weight, followed by AL, SR and HE for all three traits. An equation was derived for net returns that included parameters for feed intake and direct and maternal weaning weight. A linear programming model was designed to incorporate this equation as the objective function and determine the breeding system(s) that maximized net returns under various production conditions. In general, LR produced the greatest net returns, followed by SR and either AL or HE, depending on specific resource constraints (limited feed supply or herd size) included in the model.(ABSTRACT TRUNCATED AT 250 WORDS)

Influence of variations in biological and economical parameters on beef production net returns.

Net returns were defined as a function of the monetary returns (revenue) generated by the outputs less the monetary costs generated by the variable inputs. Outputs included total weaning weights of steers and heifers, weight of cull cows and weight of open heifers. Inputs included both feed and nonfeed costs. The net returns equation was incorporated as the objective function in a linear programming model. By maximizing the objective function, the breeding system that generated the highest net returns could be identified considering certain resource constraints. Breeding systems included purebred Herefords; small rotational dual purpose (SR), utilizing the breeds Angus, Pinzgauer, Gelbvieh and Tarentaise; large rotational (LR), a three-way rotational cross with the breeds Charolais, Simmental and Maine-Anjou; and Angus-sired terminal (AL) utilizing Angus as the sire breed and LR heifers as the maternal breed. Large rotational generally produced the greatest net returns, followed by SR and either AL or HE, depending on specific resource constraints (limited feed supply or herd size), calving rates, management systems, environment, beef to feed price ratios and purchased or farm-produced (inexpensive) feed utilized. Only under the conditions of a herd size constraint and farm-produced feed did AL exceed SR in net returns. Hereford had larger net returns than LR only when the two breeding systems were evaluated in an environment assumed to be reproductively stressful to LR. Ranking of breeding systems were dependent on specific conditions and indicated that one must consider each resource constraint and environment in which cattle are expected to produce before making breeding system recommendations.

Effect of body position on hamstring muscle group average torque.

The purpose of this investigation was to examine the effect of the supine and prone position on concentric and eccentric isokinetic strength of the hamstring muscle group. Twelve university female lacrosse players were tested for hamstring average torque on a Kinetic Communicator(R) dynamometer at 60 degrees /sec from the supine and prone positions. Analysis of variance indicated average torque generated from the prone was greater than the supine position. Greater torque was also generated during eccentric contraction than during concentric contraction. The influence of the tonic labyrinthine and the symmetrical tonic neck reflexes is proposed as the mechanism for the differences observed between the two test positions. The prone position facilitates optimal generation of torque while approximating a length-tension relationship observed during sprinting. These findings suggest consideration be given to assessment and strength training of the hamstring muscle group in the prone position. J Orthop Sports Phys Ther 1990;11(10):449-452.

Cerebral vasospasm: early detection and intervention.

Many patients survive SAH with minimal neurologic deficits but are at risk for developing further neurologic insult from ischemia resulting from cerebral vasospasm. Nursing care of the patient experiencing vasospasm is challenging. The nurse who is knowledgeable about the signs and symptoms of cerebral ischemia and necessity for continually reviewing the patient's neurologic status can initiate prompt treatment to prevent further ischemic damage. Recognition of this critical problem is the first step toward combating its ominous effects.