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Biomedical subjects

S L Collins

Publications and source records attributed to S L Collins.

35 records · Page 2Linked to original sources
PubMed1998

Peak plasma concentrations after oral morphine: a systematic review.

We performed a systematic review of 69 studies with information on 2146 subjects (454 patients and 1692 healthy volunteers) to examine the maximum plasma concentration (Cmax) and the time taken to reach maximum concentration (Tmax) for different oral morphine formulations, and to clarify factors contributing to variability. Data from healthy volunteers reflected that seen for patients but was less variable. There was minimal difference between single and multiple doses, suggesting no accumulation of morphine. For immediate-release morphine there was no difference in either dose-corrected Cmax or Tmax between solution and tablets, or between different salts. For controlled-release formulations, little difference was observed between brands. Only for once-daily formulations was there any difference in absorption between fed and fasted, with a Tmax for fed subjects considerably longer than for fasted. There was no evidence for any difference between values obtained by radioimmunoassay (RIA) or high-performance liquid chromatography (HPLC).

Administration, Oral↗
PubMed1997

Increased recurrence and metastasis in patients whose primary head and neck squamous cell carcinomas secreted granulocyte-macrophage colony-stimulating factor and contained CD34+ natural suppressor cells.

Human head and neck squamous cell carcinomas (HNSCC) that produce high levels of granulocyte-macrophage colony-stimulating factor (GM-CSF) have been shown to contain CD34+ natural suppressor cells that inhibit the activity of intratumoral T-cells. The present study evaluated whether GM-CSF production and the presence of CD34+ cells within primary HNSCC would translate into increased recurrence, metastasis or cancer-related death during the 2 years following surgical excision. Freshly excised primary HNSCC of 20 patients that subsequently developed disease, and of 17 patients that remained with no evidence of disease were analyzed for production of GM-CSF and for CD34+ cell content. The cancers of patients that subsequently developed recurrences or metastatic disease produced almost 4-fold the levels of GM-CSF and had approximately 2.5-fold the number of CD34+ cells as did cancers of patients that remained disease-free. In a second method of analysis, the prognostic significance of high vs. low GM-CSF and CD34+ cell values was evaluated. These analyses showed that patients whose cancers produced high GM-CSF levels or had a high CD34+ cell content had a disproportionately high incidence of recurrence or metastatic disease (94% and 100%, respectively), while the majority of patients whose primary cancers produced low levels of GM-CSF or had a low CD34+ cell content remained disease-free (16% and 19%, respectively). Our results indicate that the presence of CD34+ cells in GM-CSF-producing HNSCC is associated with a poorer prognosis for the cancer patients and suggest the utility of these parameters as prognostic indicators of outcome. Mechanistically, our results suggest that the presence of immune suppressive CD34+ cells in GM-CSF-producing HNSCC leads to increased tumor recurrence or metastasis.

Adult↗
PubMed1997

The longus colli muscle flap for reconstruction of the lateral pharyngeal wall.

BACKGROUND: Full-thickness lateral pharyngeal wall (LPW) defects are difficult to reconstruct, whether the larynx is preserved or removed (extended total laryngectomy). A simple, reliable reconstructive method using local tissue which optimizes wound healing and functional results would allow partial laryngectomy more often, without incurring the cost, donor site morbidity, and increased operative length of regional or free flaps. My objective was to propose use of the longus colli muscle as a reconstructive flap for defects of the LPW. METHODS: Results of using the longus colli muscle flap (LCMF) in a series of 16 patients with primary tumors of the pharyngeal wall or pyriform sinus are presented. The majority had surgery and planned postoperative radiotherapy. RESULTS: There were no wound infections or fistulas. One of 2 previously radiated patients had a transient wound-healing problem. Although 88% of the patients were stage III and IV and 50% had T3-4 primary tumors, there were only 2 local failures, for a local control rate of 88%. Corresponding cancer-free survival was 69% (median follow-up of 22 months). Two thirds of the patients took all or some food by mouth, and of the 12 with larynx preserved, 58% were decannulated, and 11 had a good to normal voice. CONCLUSIONS: The reliability of wound healing and absence of negative impact on oncologic and functional results validate use of the LCMF as a reconstructive option for defects in the LPW at both the oropharynx and hypopharynx levels.

Aged↗
PubMed1997

The visual analogue pain intensity scale: what is moderate pain in millimetres?

One way to ensure adequate sensitivity for analgesic trials is to test the intervention on patients who have established pain of moderate to severe intensity. The usual criterion is at least moderate pain on a categorical pain intensity scale. When visual analogue scales (VAS) are the only pain measure in trials we need to know what point on a VAS represents moderate pain, so that these trials can be included in meta-analysis when baseline pain of at least moderate intensity is an inclusion criterion. To investigate this we used individual patient data from 1080 patients from randomised controlled trials of various analgesics. Baseline pain was measured using a 4-point categorical pain intensity scale and a pain intensity VAS under identical conditions. The distribution of the VAS scores was examined for 736 patients reporting moderate pain and for 344 reporting severe pain. The VAS scores corresponding to moderate or severe pain were also examined by gender. Baseline VAS scores recorded by patients reporting moderate pain were significantly different from those of patients reporting severe pain. Of the patients reporting moderate pain 85% scored over 30 mm on the corresponding VAS, with a mean score of 49 mm. For those reporting severe pain 85% scored over 54 mm with a mean score of 75 mm. There was no difference between the corresponding VAS scores of men and women. Our results indicate that if a patient records a baseline VAS score in excess of 30 mm they would probably have recorded at least moderate pain on a 4-point categorical scale.

Double-Blind Method↗
PubMed1995

Mechanisms of immune suppression in patients with head and neck cancer: presence of CD34(+) cells which suppress immune functions within cancers that secrete granulocyte-macrophage colony-stimulating factor.

Production of granulocyte-macrophage colony-stimulating factor (GM-CSF) by murine tumors has been shown to induce immune suppressive cells having homology with GM progenitor cells. The purpose of this study was to determine if human head and neck cancers secrete GM-CSF, if this is associated with an intratumoral presence of similar cells expressing the hematopoietic progenitor cell antigen CD34, and if such CD34(+) cells suppress functions of intratumoral T cells. This was evaluated with fresh head and neck cancers, and in some instances regional lymph nodes and control tissue. Ten of the 14 squamous cell carcinomas (SCCs) studied secreted greater than 5 ng GM-CSF/g tissue. GM-CSF was not secreted in significant levels by either the other cancer types or by control normal muscle. Each of the high GM-CSF-secreting SCCs, but none of the cancers that did not secrete GM-CSF, contained cells expressing the hematopoietic progenitor cell antigen CD34 that had the capacity to grow into colonies in soft agar. Available regional lymph nodes from patients with high GM-CSF-producing cancers also contained CD34(+) cells. Depletion of CD34(+) cells from dissociated cancers increased interleukin 2 secretion by the intratumoral lymphocytes while addition of the CD34(+) cells to dissociated cancers reduced interleukin 2 production, indicating that the presence of CD34(+) cells within GM-CSF-producing head and neck SCCs results in suppressed functional competence of lymphocytes within the SCCs. These results show that GM-CSF-secreting SCCs contain cells expressing the hematopoietic antigen CD34 which are inhibitory to the capacity of lymphocytes within the SCCs to secrete interleukin 2.

Aged↗
PubMed1993

Severe anemia in the Jehovah's Witness: case report and discussion.

Major blood loss following trauma is common, but severe anemia is generally not life-threatening when managed with the administration of blood and blood products. Severe anemia becomes particularly challenging and potentially lethal when the patient is a Jehovah's Witness, for whom receiving a transfusion is contrary to religious principles. This case report describes the management and hospital course of a Jehovah's Witness who was seriously injured in an airplane crash.

Anemia↗
PubMed1993

Safety belt use and hospital charge differences among motor vehicle crash victims.

Trauma remains a leading cause of death and disability in America, and motor vehicle crashes (MVC) are the most common cause of serious injury in West Virginia. In this study, we examined the role of seat belt use or non-use in the death, disability, and hospital charges of 500 patients admitted after MVC to a rural Level 1 trauma center in 1990. Eighty percent of the patients who required hospitalization did not use seat belts. The unbelted patients had a 34% higher injury severity score, a 97% increase in the need for extended care after discharge from the hospital, and a 186% increase in hospital charges compared to belted patients. Our study concluded that seat belt use among motor vehicle crash victims reduced their hospital costs, and improved their outcome as compared to those patients not wearing seatbelts.

Accidents, Traffic↗
PubMed1991

The cervical sympathetic nerves in surgery of the neck.

The otolaryngologist-head and neck surgeon is aware that the cervical sympathetic nerves lie behind the carotid artery and should be avoided during neck surgery. To render this sketchy dictum more tangible, relevant anatomy and physiology of the autonomic supply to the head and neck is reviewed, as are aspects of site-of-lesion testing, with respect to Horner's syndrome. Examples of neck operations during which the cervical sympathetic chain--from the base of skull to the root of the neck--may be injured are illustrated.

Autonomic Nervous System↗
PubMed1989

Indirect videolaryngoscopy versus direct endoscopy for larynx and pharynx cancer staging. Toward elimination of preliminary direct laryngoscopy.

Thirty-nine patients with cancer of the larynx and pharynx (33 untreated and six previously treated patients) underwent tumor mapping by both direct laryngoscopy (DL) and indirect videolaryngoscopy (IVL). The examiner in each case was unaware of the findings of the other evaluation method. After definitive treatment had been carried out so that pathologic and operative information was also available, comparisons of the accuracies of the two methods of staging were made. In 32 cases, IVL provided information equal to or better than that provided by DL, and a tissue sample also could be obtained during IVL. On the basis of these findings, we conclude that aggressive, office-based IVL can guide initial treatment planning (partial or total laryngectomy versus irradiation) and patient counseling. A confirmatory DL can be performed without surprises at the time of definitive surgery, rather than as a separate procedure - a cost-effective modification of standard practice.

Biopsy↗
PubMed1987

Laryngeal chondrosarcoma as a late-appearing cause of "idiopathic" vocal cord paralysis.

A case of laryngeal chondrosarcoma is presented as a late-appearing cause of idiopathic vocal cord paralysis. Twelve cases are cited from the literature in which the cause of so-called idiopathic vocal cord paralysis was discovered with long-term followup. The natural history of idiopathic vocal cord paralysis is addressed, and recommendations for patient management are discussed.

Chondrosarcoma↗
PubMed1987

Excision of selected intraoral cancers by use of sagittal inner table mandibulectomy.

The application of oral surgery osteotomy techniques, which are used in orthognathic surgery, to excision of squamous cell carcinomas in various oral cavity locations is described and illustrated in eight cases. These methods allow the full height of the inner table of the mandible to be removed as a margin for tumors which abut the lingual mucoperiosteum without radiologic evidence of bone erosion, while jaw continuity via the intact outer cortex is maintained. These techniques can also be used for marginal mandibulectomy and horizontal maxillectomy. Discussion includes criteria for selection of cases appropriate for such conservation surgery with respect to oncologic considerations, as well as complications encountered and their prevention.

Carcinoma, Squamous Cell↗
PubMed1984

Repair of head and neck defects with thin and double-lined pectoralis flaps.

The evolution of nondelayed , single-stage repairs of extensive ablative defects of the upper aerodigestive tract with thin, skin-lined pectoralis myogenous and myocutaneous flaps is described, with particular emphasis on technique and applicability. To date, 15 such modified flap reconstructions of the oral cavity, oropharynx, and pharyngoesophagus have been performed. Other than one instance of flap failure, no significant short- or long-term complications were noted. The functional results of these repairs are equivalent to other, less convenient or technically more difficult methods of reconstruction.

Aged↗
PubMedDate not supplied

Recovery of postoperative swallowing in patients undergoing partial laryngectomy.

This study assessed the achievement of postoperative swallowing in patients undergoing partial laryngectomy surgery. Oropharyngeal swallow efficiency was used to predict time to achievement of outcome. Fifty-five patients were followed for up to 1 year in two hemilaryngectomy and four supraglottic laryngectomy groups. Within 10 days of healing, a videofluoroscopic evaluation enabled the measurement of swallowing efficiency. Times to achievement of oral intake, removal of feeding tube, preoperative diet, and normal swallow were analyzed using actuarial curves. Patients with hemilaryngectomies achieved swallowing rehabilitation sooner than patients with nonextended supraglottic laryngectomies (p < .05) who, in turn, achieved swallowing function sooner than did patients undergoing supraglottic laryngectomies with tongue base resection (p < .05). Median time to attainment of preoperative diet in these three groups was 28 days, 91 days, and > 335 days, respectively. Higher early postoperative oropharyngeal swallow efficiency was related to earlier achievement of oral food intake and of preoperative diet (p < .05). Results show that the time course for swallowing rehabilitation covers an extended postoperative period. In some surgical groups, functional swallowing and eating may be achieved within 3 months of surgery while for other types, significant impairment remains up to 9 months postoperatively Early radiographic assessments of swallowing function are useful in predicting the time to swallow recovery. Recovery of swallowing ability may be delayed in patients who have not achieved oral intake before radiotherapy is started.

Cineradiography↗