Perioperative rehydration in ambulatory anesthesia for dentoalveolar surgery

OBJECTIVE

Patient recovery after anesthesia is dependent not only on the lingering pharmacologic effects of sedatives but also on the physiologic effects that patients experience after surgery. Preoperative fasting results in a perioperative dehydration that may contribute to these physiologic effects, resulting in complaints of headache, nausea, vomiting, fatigue, lightheadedness, dizziness, and thirst. The purpose of this study was to investigate the effects of perioperative hydration in the ambulatory oral and maxillofacial surgery patient who receives deep sedation or general anesthesia (nonintubated).

STUDY DESIGN

This was a prospective, randomized, blinded study that administered either a high volume (16-17 mL/kg) or a low volume (1-2 mL/kg) of an isotonic solution to each of 77 patients who were scheduled to have their third molars extracted with deep sedation or general anesthesia. Each patient completed 3 postoperative questionnaires designed to evaluate potential adverse outcomes.

RESULTS

Nonparametric analysis of the data demonstrated a more favorable outcome with respect to subjective feelings for the high volume hydration group; this was evident both during the immediate postoperative period and in the evening of the day of surgery, and it persisted into the first postoperative day.

CONCLUSIONS

This study demonstrated that appropriate perioperative rehydration decreases postoperative adverse outcomes and improves the patient's perception of the postoperative period.

Stable transgene expression in rod photoreceptors after recombinant adeno-associated virus-mediated gene transfer to monkey retina

Recombinant adeno-associated virus (rAAV) is a promising vector for therapy of retinal degenerative diseases. We evaluated the efficiency, cellular specificity, and safety of retinal cell transduction in nonhuman primates after subretinal delivery of an rAAV carrying a cDNA encoding green fluorescent protein (EGFP), rAAV. CMV.EGFP. The treatment results in efficient and stable EGFP expression lasting >1 year. Transgene expression in the neural retina is limited exclusively to rod photoreceptors. There is neither electroretinographic nor histologic evidence of photoreceptor toxicity. Despite significant serum antibody responses to the vector, subretinal readministration results in additional transduction events. The findings further characterize the retinal cell tropism of rAAV. They also support the development of studies aimed ultimately at treating inherited retinal degeneration by using rAAV-mediated gene therapy.

Ulnar nerve pressure: influence of arm position and relationship to somatosensory evoked potentials

BACKGROUND

Although the ulnar nerve is the most frequent site of perioperative neuropathy, the mechanism remains undefined. The ulnar nerve appears particularly susceptible to external pressure as it courses through the superficial condylar groove at the elbow, rendering it vulnerable to direct compression and ischemia However, there is disagreement among major anesthesia textbooks regarding optimal positioning of the arm during anesthesia.

METHODS

To determine which arm position (supination, neutral orientation, or pronation) minimizes external pressure applied to the ulnar nerve, we studied 50 awake, normal volunteers using a computerized pressure sensing mat. An additional group of 15 subjects was tested on an operating table with their arm in 30 degrees, 60 degrees, and 90 degrees of abduction, as well as in supination, neutral orientation, and pronation. To determine the onset of clinical paresthesia compared to the onset and severity of somatosensory evoked potential (SSEP) electrophysiologic changes, we studied a separate group of 16 male volunteers while applying intentional pressure directly to the ulnar nerve. Data are presented as mean (median; range).

RESULTS

Supination minimizes direct pressure over the ulnar nerve at the elbow (2 mmHg [0; 0-23]; n = 50), compared with both neutral forearm orientation (69 mmHg [22; 0-220]; P < 0.0001), as well as pronation (95 mmHg [61; 0-220]; P < 0.0001). Neutral forearm orientation also results in significantly less pressure over the ulnar nerve compared to pronation (P < or = 0.04). The estimated contact area of the ulnar nerve with the weight-bearing surface was significantly (P < 0.0001) smaller in the supine position (2.2 cm2 [0.5; 0-9]; n = 50) compared with both neutral orientation (5.5 cm2 [5.0; 0-13]) and pronation (5.8 cm2 [6; 0-12]). With the forearm in neutral orientation, ulnar nerve pressure decreased significantly (P < or = 0.01; n = 15) as the arm was abducted at the shoulder from 0 degrees to 90 degrees. In the 16 male subjects tested, notable alterations in ulnar nerve SSEP signals (decrease > or = 20% in N9-N9' amplitude) were detected in 15 of 16 awake males during application of intentional pressure to the ulnar nerve. However, eight of these subjects did not perceive a paresthesia, even as SSEP waveform amplitudes were decreasing 23-72%. Two of these eight subjects manifested severe decreases in SSEP amplitude (> or = 60%).

CONCLUSIONS

Extrapolating these results to the clinical setting, the supinated arm position is likely to minimize pressure over the ulnar nerve. With the forearm in neutral orientation, pressure over the ulnar nerve decreases as the arm is abducted between 30 degrees and 90 degrees. In addition, up to one half of male patients may fail to perceive or experience clinical symptoms of ulnar nerve compression sufficient to elicit SSEP changes.

Caring for people with HIV in Zambia: are traditional healers and formal health workers willing to work together?

This study of traditional healers and formal health workers determined their knowledge and practices in the field of HIV/AIDS and examined their training needs and attitudes to collaboration, in preparation for planning joint training workshops. Several misconceptions concerning symptoms and transmission of HIV disease were found in both groups, particularly among traditional healers. Twenty healers (51%) and four formal health workers (15%) claimed a cure existed for AIDS. The majority of traditional healers interviewed expressed difficulties discussing a diagnosis of HIV directly with patients, mainly due to fear of the patient becoming depressed and suicidal. Most interviewees wanted more training--the majority of traditional healers in recognizing symptoms of HIV/AIDS and their treatment, and the majority of formal health workers in HIV counselling. Most were interested in supplying condoms. Almost all healers and half of the formal health workers were keen to collaborate in training and patient care. The study indicates that there is willingness amongst Zambian traditional healers and formal health workers to collaborate in training and patient care in the field of HIV/AIDS. As well as covering symptoms, transmission and prevention of HIV/AIDS, training should aim to increase ability to openly discuss HIV with patients, which many traditional healers and some formal health workers find difficult. Involving traditional healers in supplying condoms may improve acceptability and availability, particularly in rural areas.

bcl-2 gene therapy exacerbates excitotoxicity

The protooncogene bcl-2 can block neuronal death from both naturally occurring apoptosis and exogenous insults. bcl-2 is therefore a promising candidate for the prevention of excitotoxic neuronal death. Using an adeno-associated viral vector, we delivered the bcl-2 gene to the ganglion cell layer of the rat eye. We hypothesized that infection with bcl-2 would protect ganglion cells against excitotoxic cell death. However, retinal infection with bcl-2 increased ganglion cell susceptibility to both axonal injury and intravitreal NMDA. Our study--intended to explore the possibility of bcl-2 transduction as an in vivo therapeutic approach--revealed a deleterious effect of bcl-2 transduction.

Persistent transgene product in retina, optic nerve and brain after intraocular injection of rAAV

Recombinant adeno-associated virus (rAAV) is a promising vector for retinal application as it transduces photoreceptors and retinal pigment epithelium cells efficiently and in a stable fashion. Because rAAV also transduces retinal ganglion cells, we reasoned that ocular application of rAAV might result in delivery of transgenic protein to the CNS. Here we describe high levels of green fluorescent protein (GFP) persisting at least 6 months in optic nerves and brains of mice and dogs after intravitreal delivery of rAAV-GFP. There was no clinical or histological evidence of inflammatory response although a mild humoral Th-2 response to viral capsid proteins was detected. These findings have important implications with respect to therapeutic applications of rAAV.

Results of a randomized double-blind placebo-controlled trial evaluating sequential high-dose cytosine arabinoside/mitoxantrone chemotherapy with or without granulocyte/macrophage-colony-stimulating factor in high-risk myelodysplastic syndromes

A prospective, randomized, double-blind placebo-controlled trial was designed to evaluate the impact of granulocyte/macrophage-colony-stimulating factor (GM-CSF) on the efficacy of sequential high-dose cytosine arabinoside/mitoxantrone chemotherapy (S-HAM) in adult patients with high-risk myelodysplastic syndromes (MDS). GM-CSF or placebo was given subcutaneously once daily at a dose of 250 microg/m2, starting 48 h prior to chemotherapy, and continued until neutrophil recovery. Owing to high toxicity and slow patient recruitement the study was closed and unblinded after 31 patients had been enrolled; 15 were randomized to receive placebo and 16 to receive GM-CSF. A total of 29 patients were evaluable for response; their median age was 57 years. Ten patients achieved a complete remission (34.5%), 9 patients had persistent MDS (31%), 10 patients died within 6 weeks after the onset of treatment (early death) (34.5%). The median remission duration was 190 days (range: 2.5-45 months). Among the 29 evaluable patients no significant differences could be found between the two study arms regarding complete remission rate [GM-CSF: 31% (5/16) versus placebo: 38% (5/13) P = 0.45], rate of persistent MDS [GM-CSF: 25% (4/16) versus 38% (5/13) P = 0.35), early death rate [44% (7/16) versus 23% (3/13) P = 0.22] and remission duration (GM-CSF: 87 days versus placebo 221 days). Duration of granulocytopenia (median: 33 days with GM-CSF) versus 35 days with placebo) and frequency of infectious episodes were not significantly influenced by GM-CSF. The small number of patients finally analyzed means that no definite conclusions about the effect of GM-CSF can be reached.

A nasopalatine cyst in an 8-year-old child

The nasopalatine cyst (NPC) was first described in 1914 and it is considered the most common non-odontogenic cyst. Most studies show a higher incidence of NPC among males than females, with a male/female ratio of 1.7:1. The majority of the cases described in people in their fifth decade involve Afro-Caribbeans, while those in their sixth decade are mainly caucasians. These cysts are normally asymptomatic, unless they are infected. The most commonly reported clinical symptom is swelling in the anterior part of the palate. The treatment of choice is enucleation. Even though it has been stated that NPCs may occur at any age no reports have been made on children less than 9 years old. Some reports support a predisposition in young Afro-Caribbeans, where NPCs appear to be more aggressive, larger and symptomatic. We present a case of a NPC in an 8-year-old caucasian female.

Technique for placement of non-end-hole nasojejunal feeding tubes

The authors describe a simple method for placing a non-end-hole nasojejunal feeding tube with fluoroscopic guidance by using a multipurpose catheter and guide wire. The method was used successfully in 12 patients with no side effects or complications.

Long-term followup of the North American multicenter UroLume trial for the treatment of external detrusor-sphincter dyssynergia

PURPOSE

We determine the long-term efficacy and safety of the UroLume stent as minimally invasive treatment for external detrusor-sphincter dyssynergia in spinal cord injured men.

MATERIALS AND METHODS

A total of 160 spinal cord injured men with a mean age plus or minus standard deviation of 36.3 +/- 12.1 years (range 16 to 74) were prospectively treated with an endoprosthesis at 15 centers as part of the North American UroLume trial for external detrusor-sphincter dyssynergia. Urodynamic parameters, including voiding pressure, residual urine volume and bladder capacity, were compared before treatment and at 1, 2, 3, 4 and 5 years after treatment.

RESULTS

Mean voiding pressure was 75.1 +/- 28.2 cm. water before treatment in the 160 patients, and 37.4 +/- 23.9 at year 1 in 97, 39.5 +/- 22.2 at year 2 in 84, 42.6 +/- 27.3 at year 3 in 61, 46.3 +/- 33.2 at year 4 in 57 and 44.2 +/- 28.9 cm. at year 5 in 41 after stent insertion (p <0.001). Residual urine volume decreased after stent placement and was maintained throughout the 5-year followup (p <0.001). Mean cystometric capacity remained constant from 269 +/- 155 before insertion to 337 +/- 182 ml. 5 years later (p = 0.17). Hydronephrosis and autonomic dysreflexia improved or stabilized in most patients with functioning stents. Stent explant was necessary in 24 patients (15%), of whom 4 (16.7%) had another stent implanted.

CONCLUSIONS

The UroLume stent demonstrates long-term safety and efficacy for the treatment of external detrusor-sphincter dyssynergia. The outcome was similar in men with and without previous sphincterotomy.

Position of the internal jugular vein in children. A study of the anatomy using ultrasonography

The relative anatomy of the internal jugular vein (IJV) was studied in 25 patients undergoing cardiac catheterization under general anaesthesia, with the use of a portable ultrasound probe. In 14 of cases the IJV was anterior, 1 anterolateral and in 10 lateral to the carotid artery between the two heads of the sternocleidomastoid muscle. At the level of the cricoid cartilage, in six cases the IJV was anterior, three anterolateral and in 16 of children the IJV was lateral to the carotid artery. When attempting to cannulate the IJV, because of the variability in relationship of the IJV to CA the technique used should be modified depending upon the level at which cannulation is attempted. The position of the IJV in the child appears to be so variable extra care should be taken when cannulating the IJV and it should not be assumed that the techniques used in adults are directly transferable.

Circumcision and neonatal tetanus: disclosure of risk and its reduction by topical antibiotics

BACKGROUND

Previous case-control studies have paradoxically suggested that circumcisions protect against neonatal tetanus (NNT), but these observations have not been adjusted for differences in the length of survival of cases and controls.

METHODS

Boy cases (n = 133) and their sex-matched controls (n = 399) were extracted from a population-based study of NNT undertaken in Punjab Province, Pakistan. In the resulting file, circumcisions were censored such that analysis was restricted to only those that occurred before onset in cases or before age of onset in the matched case for controls. The effect of topical antibiotics in circumcision wounds was then evaluated.

RESULTS

After adjusting for confounders, circumcision before onset posed a significant risk for NNT (matched odds ratio [OR] = 3.1, 95% CI: 1.2-8.0). The risk of NNT in those circumcised before onset and treated with topical antibiotics did not differ significantly from the referent group who had not been circumcised before onset (matched OR = 1.1, 95% CI: 0.2-6.8), whereas the lack of topical use was associated with significant risk (matched OR = 4.2, 95% CI: 1.4-12.6). This suggests that topical antibiotics are likely to be highly effective in preventing NNT from circumcision wounds. We estimated an overall risk of about 16 fatal NNT cases per 1000 live boy births with circumcision wounds that were not protected by topical antibiotics, and that circumcision and umbilical wounds each accounted for about half of this overall risk in these boys.

CONCLUSIONS

Topical antibiotics should be routinely applied to all wounds created by traditional circumcisions, to prevent NNT and sepsis from these frequently unsterile procedures.

Antipsychotic drug treatment

This article discusses the clinical use, action and effectiveness of antipsychotics and methods of improving compliance with treatment regimes.

Seroconversions in unvaccinated infants: further evidence for subclinical measles from vaccine trials in Niakhar, Senegal

BACKGROUND

Increases in measles antibodies without rash-illnesses have been documented in previously vaccinated children exposed to measles cases. The phenomenon has been incompletely evaluated in young unvaccinated infants with immunity of maternal origin.

METHODS

Monthly cohorts of newborns were prospectively randomized to vaccine and placebo control groups during a trial of high-titre vaccines in Niakhar, Senegal. Measles antibodies were assayed in blood samples of enrolled children collected at 5 months old, when controls received a placebo injection, and at 10 months, when the placebo group was given measles vaccine. Intensive prospective surveillance for measles was conducted throughout the trial.

RESULTS

One-fifth (n = 53) of the placebo controls seroconverted, with known exposure to a measles case in only three of them. None of the seroconverters developed a measles-like rash. Sixteen-fold or greater increases in titres were noted in about one-quarter of them. Compared with placebo controls who did not seroconvert, seroconverters were more likely to have had exposure to a measles case and to travel, more likely to be boys than girls, and had significantly lower baseline antibody titres. Measles was endemic in the study area throughout the trial. Seroconversions did not adversely effect subsequent nutritional indices or mortality.

CONCLUSIONS

Although laboratory errors and inadvertent injection of vaccine rather than placebo may have played some role, they do not fully explain the above observations, which are consistent with subclinical measles in the seroconverters. The possible role of subclinical measles in occult transmission, its potential effect on the type and duration of subsequent immunity, and its impact on response to primary vaccination need to be determined.

Medication adherence in rheumatoid arthritis patients: older is wiser

OBJECTIVES

To create a profile of individuals nonadherent to their medications in an age-stratified sample (ages 34-84) of community-dwelling rheumatoid arthritis patients. The relative contributions of age, cognitive function, disability, emotional state, lifestyle, and beliefs about illness to nonadherence were assessed.

DESIGN

A direct observation approach was used in conjunction with structural equation modeling. All participants were administered a preliminary assessment battery. Medications were then transferred to vials with microelectronic caps that recorded medication events for all medications for the next 4 weeks.

PARTICIPANTS AND SETTING

A volunteer sample of 121 community-dwelling rheumatoid arthritis (RA) patients were recruited from newspaper ads, posters, and via informal physician contact from private rheumatology practices in Atlanta and Athens, Georgia. Written verification of the RA diagnosis and a disease severity rating were obtained from personal physicians before patients were enrolled in the study. Patients were tested in a private physician's office, and their medication adherence was monitored electronically for a month in their every-day work and home settings.

MEASUREMENTS AND RESULTS

Structural equation modeling techniques were used to develop a model of adherence behavior. Cognitive and psychosocial measures were used to construct latent variables to predict adherence errors. The model of medication adherence explained 39% of the variance in adherence errors. The model demonstrated that older adults made the fewest adherence errors, and middle-aged adults made the most. A busy lifestyle, age, and cognitive deficits predicted nonadherence, whereas coping with arthritis-related moods predicted adherence. Illness severity, medication load, and physical function did not predict adherence errors. Omission of medication accounted for nearly all errors.

CONCLUSION

Despite strong evidence for normal, age-related cognitive decline in this sample, older adults had sufficient cognitive function to manage medications. A busy lifestyle and middle age were more determinant of who was at risk of nonadherence than beliefs about medication or illness. Thus, practicing physicians should not assume that older adults have insufficient cognitive resources to manage medications and that they will be the most likely to make adherence errors. Very busy middle-aged adults seem to be at the greatest risk of managing medications improperly.

Effect of subclinical infection on maintaining immunity against measles in vaccinated children in West Africa

BACKGROUND

Despite a high coverage with measles vaccines in parts of west Africa, epidemics of measles occur with reduced severity in an increasing proportion of older children who have been vaccinated. We examined the effect of exposure to natural measles on immunity in vaccinated children.

METHODS

Our study was carried out in 1992 during an epidemic of measles in Niakhar, a rural area of Senegal with about 27,000 inhabitants who mostly live in compounds that include several households; within each household people live in different huts. Vaccine coverage in Niakhar was 81% at the time of our study. We measured haemagglutinin-inhibiting antibody at exposure and twice thereafter (after 4-5 weeks and at 6 months) in 36 vaccinated and 87 unvaccinated children. The frequency of measles and subclinical measles--defined as a four-fold or greater rise in antibody titre without clinical signs or symptoms--was related to intensity of exposure according to whether the index case was in the same hut, household, or compound.

FINDINGS

Clinical measles occurred in 20 (56%) of 36 unvaccinated children and in one (1%) of 87 vaccinated children. Subclinical measles occurred in 39 (45%) of 86 vaccinated children who were exposed to measles and in four (25%) of 16 unvaccinated children. The frequency was inversely related to pre-exposure antibody concentration (p<0.001 for trend) and directly related to intensity of exposure (p=0.002 for trend). Antibody concentrations in subclinical cases increased on average by 45-fold and remained raised for at least 6 months.

INTERPRETATION

Increased antibody titre after subclinical measles may be common in vaccinated children in West Africa where the intensity of exposure is high. As measles vaccination coverage increases, the circulation of wild measles will decrease, and vaccine-induced antibody is less likely to be boosted. Thus, new epidemics, albeit milder in form, may occur in vaccinated areas which should be recognised in campaigns to eradicate measles.

Increased long term mortality associated with rash after early measles vaccination in rural Senegal

OBJECTIVES

To examine whether clinical symptoms, including rash, were more common after measles immunization compared with placebo and to study the association between postvaccination symptoms and later mortality.

DESIGN

Examination of side effects in the 3 weeks after immunization in a trial of high titer and standard titer measles vaccines.

PATIENTS

Two hundred twenty-four children randomly selected to be included in the surveillance for diarrhea, fever and rash.

RESULTS

There was no difference in fever and diarrhea between recipients of high titer vaccines and recipients of placebo. However, high titer recipients tended to have more measles-like rashes than placebo recipients [relative risk, 2.12 (range, 0.90 to 5.03)]. Among recipients of high titer vaccines, children who presented a rash had higher mortality in the following 5 to 7 years than those who did not develop rash [mortality rate ratio, 3.85 (range, 1.52 to 9.79)]. High titer recipients without a rash had the same mortality as children in the placebo group who were given standard doses of measles vaccine at 10 months of age [mortality rate, 0.76 (range, 0.35 to 1.62)].

CONCLUSIONS

These observations suggest that in this particular study, rash after high titer measles vaccine may identify children who received a particularly high dose of vaccine or children with more severe and persistent postvaccination immunosuppression. Whether high titer vaccine is more likely than standard titer measles vaccine to provoke such reaction is not known, given that we did not compare side effects after different titers of measles vaccine. Future trials of live measles vaccine should monitor the development of rash.

Poor serologic responses five to seven years after immunization with high and standard titer measles vaccines

BACKGROUND

Few data exist on the persistence of measles antibodies after vaccination of West African infants. Therefore we examined measles antibody titers 5 to 7 years after children in rural Senegal had received high titer Edmonston-Zagreb (EZ-HT), high titer Schwarz (SW-HT) or standard titer Schwarz (SW-STD) measles vaccines in infancy.

METHODS

Children had received either high titer vaccines at 5 months of age or standard titer at 10 months of age. Finger prick blood samples were tested for measles antibody 5 to 7 years later by the hemagglutinin inhibition test.

RESULTS

Persistence of antibody after high titer vaccines was poor with the result that 39 and 50% of the EZ-HT and the SW-HT groups had low titers of hemagglutinin inhibition measles antibodies (< or =125 mIU/ml). Nineteen percent of the children in the SW-STD group had low titers which is a lower prevalence than in the high titer groups [relative risk (95% confidence intervals), 0.05 (0.28 to 0.88) vs. EZ-HT; relative risk, 0.38 (0.22 to 0.66) vs. SW-HT]. Geometric mean (95% confidence interval) antibody titers in children with detectable values were 616 (435 to 871) in the EZ-HT, 1106 (616 to 1866) in the SW-HT and 1271 (871 to 1741) mIU/ml in the SW-STD groups, respectively. Multivariant regression analysis showed that mean titers were 2.00 (1.03 to 3.89) times higher for children with low prevaccination antibody titers (< or =125 mIU/ml) and 3.06 (1.90 to 4.94) times higher if blood was collected in the rainy season.

INTERPRETATION

Given the rapid decline in antibody titers over a 5- to 6-year period in an area where measles vaccine coverage was high, it seems likely that multiple dose immunization schedules will be needed in the future to maintain protective antibody concentrations (>125 mIU/ml) in West Africa. The role of subclinical boosting by exposure to natural measles and the possible role of malaria, which increases immunoglobulin turnover, in influencing long term antibody persistence after vaccination deserve further investigation.

A spatial correlation based method for neighbor set selection in random field image models

Random field (RF) models have widespread application in image modeling and analysis. The effectiveness of these models is largely dependent on the choice of neighbor sets, which determine the spatial interactions that are represented by the model. We consider the problem of selecting these neighbor sets for simultaneous autoregressive and Gauss-Markov random field models, based on the correlation structure of the image to be modeled. A procedure for identifying appropriate neighbor sets is proposed, and experimental results which demonstrate the viability of this method are presented.

Subcutaneous administration of midazolam: a comparison of the Bioject jet injector with the conventional syringe and needle

PURPOSE

The purpose of this study was to compare jet injection to a syringe and needle in terms of the difference in discomfort and pharmacokinetics after the subcutaneous administration of midazolam.

PATIENTS AND METHODS

Using a prospective, randomized, double-blinded study design, 14 subjects were administered midazolam on two separate occasions (at least 2 weeks apart). The subjects were randomly distributed into two groups: syringe and needle (saline)/jet injector (midazolam) or syringe and needle (midazolam)/jet injector (saline). The subjects were randomly assigned to receive either EMLA (eutectic mixture of local anesthetics) or a placebo at the injection site for the first administration and the other topical agent on the second visit. Each subject received one subcutaneous injection in the deltoid region per arm per day. Each injection contained the same volume of solution. Subjects completed visual analog scale (VAS) questionnaires assessing the discomfort of the injection. Blood samples were taken at specified intervals over 2 hours for determination of midazolam levels.

RESULTS

The discomfort associated with the injection was less with the Biojector 2000 (Bioject Inc, Portland, OR) although this was not statistically significant. However, persistent discomfort was significantly greater at the needle site. The mean peak plasma level of midazolam was achieved more rapidly with the Biojector 2000 than with the syringe and needle (P < .05). However, the peak plasma level after jet injection or injection with a syringe and needle was not statistically different.

CONCLUSION

The results of the study show that the Biojector 2000 is a needle-free injection system that can be used for the administration of a premedicant before induction of anesthesia. It has several advantages, including the potential reduction of anxiety associated with the "fear of needles" and occupational injuries.

Fear of contagion: a response to stress?

Most of the research on nurses' responses to people affected by AIDS has comprised atheoretical surveys or cross-sectional correlation studies. A decade ago, Meisenhelder and LaCharite were among the first to propose a theoretical explanation for these responses, including implications for altering them. They posited that "fear of contagion [is] an affective response of the stress-coping process ... [and] highlighted origins of the fear, behavioral manifestations, and avenues for exploration to decrease this perceived threat." This article reexamines the interpretation of the empirical data on which their proposition rested, places that data in the context of other research about the nurses' AIDS-care attitudes, including Meisenhelder's own subsequent research, and discusses the model's utility for anticipating and influencing nurses' behavioral response to HIV-affected populations.

Incremental bolus versus a continuous infusion of propofol for deep sedation/general anesthesia during dentoalveolar surgery

PURPOSE

This article compared the use of the traditional incremental bolus technique with the continuous infusion technique for the administration of propofol for deep sedation/general anesthesia.

PATIENTS AND METHODS

Patients were sedated with midazolam and fentanyl and then had maintenance of an anesthetic state achieved with propofol administered by either of the two techniques. Data were collected to evaluate the overall surgical/anesthetic procedure, movement of the patient, and his or her hemodynamic status.

RESULTS

Both groups received a mean maintenance dose of propofol exceeding 6 mg/kg/hr. However, the patients in the continuous infusion group received a statistically greater maintenance dose (continuous infusion + supplemental vs incremental bolus). All patients were maintained in a deep sedation/general anesthetic state. Respiratory and blood pressure values were comparable in both groups. However, the continuous infusion group showed improved hemodynamic stability manifested as fewer fluctuations in heart rate. Visual analog scale (VAS) questionnaires completed by the surgeon and surgical assistant reported less patient movement and improved surgical/anesthetic conditions with the continuous infusion technique. Recovery of the two groups was comparable.

CONCLUSION

This study, although finding advantages in the continuous infusion technique, showed satisfactory conditions associated with both techniques.

Adenovirus-mediated delivery of rhodopsin-promoted bcl-2 results in a delay in photoreceptor cell death in the rd/rd mouse

Gene transfer to retinal cells may provide a means to retard photoreceptor cell death and thus prevent blindness in diseases such as retinitis pigmentosa. We tested the possibility of interfering with apoptotic photoreceptor cell death in the rd mouse through subretinal delivery of a recombinant replication-defective adenovirus containing the human cDNA for bcl-2, Ad.2.5HRPbcl-2. Photoreceptor-specific transgene expression was accomplished through incorporation of the 2.5 kb human rhodopsin upstream fragment (HRP). Ad.2.5HRPbcl-2 was injected alone or in combination with Ad.CMVPDE beta. Ad.CMVPDE beta contains a cDNA encoding the beta subunit of cGMP phosphodiesterase (PDE beta). Recombinant viruses containing lacZ (driven either by the cytomegalovirus (CMV) promoter/enhancer or HRP) and of Ad.CMVPDE beta and vehicle alone were injected in contralateral eyes as control. Injection of Ad.2.5HRPbcl-2 in the rd mouse resulted in histologically detectable rescue lasting 6 weeks after birth. Extent of rescue was not as large as after delivery of wildtype PDE beta, the gene defective in the rd mouse. However, delivery of genes which prevent apoptotic cell death may have broad application to gene therapy of retinal degenerative diseases.