Maternal and preterm fetal sheep responses to dexmedetomidine.

BACKGROUND: The α(2) adrenergic receptor agonist dexmedetomidine has some unique pharmacologic properties that could benefit pregnant patients (and their fetuses) when they require sedation, analgesia, and/or anesthesia during pregnancy. The purpose of the present study was to delineate maternal and fetal responses to an intravenous infusion of dexmedetomidine. METHODS: This study was conducted on surgically-recovered preterm sheep instrumented for physiologic recording and blood sampling. Maternal and fetal cardiovascular and blood gas parameters and fetal cerebral oxygenation levels were recorded before, during, and after 3h of dexmedetomidine infusion to the ewe at a rate of 1 µg/kg/h. RESULTS: Drug infusion produced overt sedation but no apparent respiratory depression as evidenced by stable maternal arterial blood gases; fetal blood gases were also stable. The one blood parameter to change was serum glucose, By the end of the 3-h infusion, glucose increased from 49±10 to 104±33mg/dL in the ewe and from 22±3 to 48±16mg/dL in the fetus; it declined post-drug exposure but remained elevated compared to the starting levels (maternal, 63±12mg/dL, P=0.0497; and fetal, 24±4mg/dL, P=0.012). With respect to cardiovascular status, dexmedetomidine produced a decrease in maternal blood pressure and heart rate with fluctuations in uterine blood flow but had no discernable effect on fetal heart rate or mean arterial pressure. Likewise, maternal drug infusion had no effect on fetal cerebral oxygenation, as measured by in utero near-infrared spectroscopy. CONCLUSIONS: Using a clinically-relevant dosing regimen, intravenous infusion of dexmedetomidine produced significant maternal sedation without altering fetal physiologic status. Results from this initial acute assessment support the conduct of further studies to determine if dexmedetomidine has clinical utility for sedation and pain control during pregnancy.

Percutaneous cervical oesophageal cannulation in the dog for the performance of prolonged oesophageal pH and manometric studies.

Traditional methods for obtaining oesophageal access in experimental animals are unsuitable for prolonged (24 h) oesophageal pH evaluation, a procedure that is commonly employed in the assessment of human patients suspected of having gastroesophageal reflux disease. In the present study, we describe a six-year experience with a technique of percutaneous oesophagostomy for the performance of serial 24 h oesophageal pH and manometric studies involving 62 dogs and a total of 208 oesophageal cannula placement procedures. The results indicate a considerable improvement over previously described techniques with respect to simplicity of surgical technique, associated morbidity, oesophagostomy management, animal conditioning, and avoidance of chemical and excessive physical restraints in animals undergoing oesophageal pH and manometric evaluation.

The use of acridine orange staining and image analysis to detect bacteriuria.

Fifty urine samples from a variety of urological patients were analysed using the fluorochrome acridine orange in an automated system. The results were compared with standard colony counts. The method has a potential value in the detection of significant infection particularly in population studies.

The screening of more than 2,000 schoolgirls for bacteriuria using an automated fluorescence microscopy system.

After initial evaluation of a manual fluorescence microscopy system on a variety of urines the method was automated and subsequently tested in a population survey of urinary tract infection in schoolgirls. This automated Bactoscan system allowed a rapid analysis of urine samples and with the introduction of modifications to the staining protocol it correctly eliminated 91% of samples as being not significantly infected.

A survey of bacteriuria in 2,234 schoolgirls in a Scottish new town.

The prevalence of urinary tract infection in a modern Scottish town has been ascertained in female school children aged 5-12. In 2,234 girls the initial prevalence of urinary tract infection is 3.3%. In addition to the information on urinary tract infection the social and personal history was available including data on incontinence, enuresis and current antibiotic therapy. The necessity to have a system available which allows a cheap and rapid assessment of population surveys is made.

Mucosal enteritis: a complication of the continent ileostomy.

Mucosal enteritis, a nonspecific inflammation of both the mucosa and submucosa, is a complication seen in 13 per cent to 43 per cent of patients with a continent ileostomy. Six cases are presented with emphasis on history, diagnosis, and treatment. Because the inflammation is secondary to an overgrowth of anaerobic bacteria in a functional blind loop, treatment consists of drainage and antibiotics. Metronidazole may be the drug of choice. Refractory cases will benefit only by resection and conversion to a Brooke ileostomy.

An expedient lid retracter.

An expedient lid retractor may be fashioned from a paper clip.

Squamous cell carcinoma of the anus.

The institution of proper therapy for squamous cell carcinoma of the anus requires an intimate knowledge of the histology and anatomy of this region. It also requires an awareness of the disease entity by the physician and a realization that everything that bleeds around the anus is not due to hemorrhoidal disease. Once the diagnosis and extent of the disease are established, several known facts can be applied in the decision for specific therapy. For small lesions (less than 3 cm in diameter) located in the perianal skin, it is now clear that wide local excision, usually with skin graft, is a safe, reliable method of treatment. However, if these lesions are invading deeply, one should resort to a more radical form of therapy. The combined abdominoperineal resection is the definitive treatment for lesions in the anal canal. In this way, local recurrence can be prevented insofar as possible, invasive lesions can be completely eradicated, and patients with lymph node involvement will be given the greatest opportunity for survival. As is the case in all radical types of therapy, the anal sphincter mechanism of a few patients will be sacrificed unnecessarily. If a lesion is located in the anal canal and does not invade beyond the submucosa, such as those lesions discovered during routine hemorrhoidectomy, it might be safe to undertake wide local excision of the region. Precise pathologic study must be available, however, and the patient must be apprised of this compromise in management and be willing to be examined frequently for evidence of recurrent disease. With present knowledge and development of the operation, radical removal of inguinal lymph nodes should be undertaken when the nodes are thought to contain tumor. It must be realized, however, that the overall salvage rate in this situation is low. Finally, the treatment of recurrent and metastatic squamous cell carcinoma of the anus remains a great dilemma. The first choice of treatment for local recurrence should be excision whenever possible. Radiation may have some value, but excellent responses are rare. Lastly, several chemotherapeutic regimens are available for use in specific cases.