A Review of Physiology and Pharmacology Related to Acute Perioperative Pain Management.

Perioperative pain is a major fear for many patients undergoing simple and complex surgical procedures. Pain management continues to present challenges for the anesthesia provider who is continually striving for the balance between undertreatment and overtreatment of pain. Traditional management pharmacology has proved effective but is not without risks. The purpose of this article is to provide the practicing anesthesia provider with a review of pain transmission physiology and pharmacology and to present new and emerging pain management pharmacologic agents and strategies. The authors declare they have no financial relationships with any commercial entity related to the content of this article. The authors did not discuss off-label use within the article.

Oropharyngeal Edema in an 8-Month-Old Girl after Woolly Bear Caterpillar Exposure.

BACKGROUND: Lepidopterism refers to the manifestations of contact from any number of moths, butterflies, and caterpillars. Various symptoms have been described, ranging from localized skin irritation to systemic anaphylactic reactions. CASE REPORT: We present a case of airway edema in an 8-month-old child from oral exposure to Woolly Bear Caterpillar (Pyrrharctia Isabella). After prompt emergency department recognition, her symptoms necessitated urgent operating room management by a team of otolaryngologists and close monitoring in a pediatric intensive care unit. A similar presentation in this species has not been described previously in the English literature. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Leptidopterism is rare, but recognition by the emergency practitioner is necessary for prompt and appropriate treatment. Rapid identification by the emergency physician of oral exposure and careful spine removal can be lifesaving in cases of significant oropharyngeal edema.

Can emergency physicians accurately rule out clinically important cervical spine injuries by using computed tomography?

OBJECTIVE: Emergency physicians are expected to rule out clinically important cervical spine injuries using clinical skills and imaging. Our objective was to determine whether emergency physicians could accurately rule out clinically important cervical spine injuries using computed tomographic (CT) imaging of the cervical spine. METHOD: Fifteen emergency physicians were enrolled to interpret a sample of 50 cervical spine CT scans in a nonclinical setting. The sample contained a 30% incidence of cervical spine injury. After a 2-hour review session, the participants interpreted the CT scans and categorized them into either a suspected cervical spine injury or no cervical spine injury. Participants were asked to specify the location and type of injury. The gold standard interpretation was the combined opinion of two staff radiologists. RESULTS: Emergency physicians correctly identified 182 of the 210 abnormal cases with cervical spine injury. The sensitivity of emergency physicians was 87% (95% confidence interval [CI] 82-91), and the specificity was 76% (95% CI 74-77). The negative likelihood ratio was 0.18 (95% CI 0.12-0.25). CONCLUSION: Experienced emergency physicians successfully identified a large proportion of cervical spine injuries on CT; however, they were not sufficiently sensitive to accurately exclude clinically important injuries. Emergency physicians should rely on a radiologist review of cervical spine CT scans prior to discontinuing cervical spine precautions.

Continuous IV Crotalidae Polyvalent Immune Fab (Ovine) (FabAV) for selected North American rattlesnake bite patients.

BACKGROUND: In patients bitten by North American rattlesnakes and treated with Crotalidae Polyvalent Immune Fab (Ovine) (FabAV), late hematologic abnormalities-persistent, recurrent, or late, new onset of hypofibrinogenemia, prolonged PT/INR, prolonged PTT, and/or thrombocytopenia beyond 48 h post-envenomation-are common, difficult to manage, and may result in morbidity and mortality are common, difficult to manage, and may result in morbidity and mortality. The optimal management of late hematologic abnormalities, particularly the use of further treatment with antivenom, has not been well defined. The current FabAV treatment regimen is to give antivenom as a bolus dose over a one-hour period. We describe our experience using a continuous intravenous infusion of FabAV for late hematologic effects and/or associated bleeding complications in rattlesnake envenomation. METHODS: This is a retrospective, observational case series of patients envenomated by North American rattlesnakes at three medical centers managed with a continuous intravenous infusion of FabAV for late hematologic abnormalities and/or associated bleeding complications. Indications, dilution and infusion protocols, and duration of therapy were individualized. RESULTS: Five cases were identified between July 2010 and September 2011. All patients had profound late hematologic abnormalities and/or were associated with bleeding complications. Several patients had received repeat bolus infusions of FabAV, with or without human blood products, with either inadequate or only transient beneficial response. All patients were then managed with a continuous intravenous infusion of FabAV and all appeared to respond to the continuous intravenous infusion of FabAV, titrated to effect, with cessation of progression and, in most cases, improvement in hematologic abnormalities. Rates of infusion varied from 2 to 4 vials per 24 h (mean = 3.1 ± 0.4 vials/day). The termination of FabAV infusion was between day 6 and day 14 from the time of envenomation (mean = 10 ± 3 days), after which hematologic values were normalized or were normalizing in all patients and continued to do so. DISCUSSION: The use of FabAV as a continuous intravenous infusion, particularly after the acute phase of envenomation has passed, provides a continuous source of circulating antibodies to neutralize venom components reaching circulation from tissue stores and allows natural replenishment of hematologic factors such as platelets and/or fibrinogen. This method is an efficient use of FabAV, avoiding the wasteful excess of a bolus dose, may be more effective, eliminating the potential for destruction of hematologic factors when protective antivenom levels are lost between bolus FabAV doses, and appears to be safe. Further assessments of the stability and sterility of the product during infusion are needed. The need to continue hospitalization is the major drawback, but continued observation and inpatient care may be needed for other indications (e.g. bleeding) in this subset of patients. CONCLUSIONS: A continuous intravenous infusion of FabAV between 2 and 4 vials per day, titrated to effect, and continued for 6-14 days post-envenomation appeared to be associated with reversal of late hematologic effects of rattlesnake envenomation and, when combined with indicated human blood products, control of significant bleeding. Continuous intravenous infusion of FabAV may be safer, more efficacious, and more cost-effective than observation without FabAV treatment or as-needed bolus dosing in selected patients with late hematologic abnormalities.

American association of poison control centers database characterization of human tilmicosin exposures, 2001-2005.

BACKGROUND: Tilmicosin is a veterinary antibiotic with significant human toxicity at doses commonly used in animals, but the parenteral dose-response relationship has not been well characterized. METHODS: Human exposures to tilmicosin in the database of the American Association of Poison Control Centers (AAPCC) from 2001 to 2005 were analyzed for demographic associations, exposure dose, clinical effects and outcomes. RESULTS: Over the 5-year period, there were 1,291 single-substance human exposures to tilmicosin. The mean age was 39.1 years, and 80% were male. By route there were 768 (54%) parenteral exposures. Patients with parenteral exposures had a significantly increased likelihood of being seen at a healthcare facility, admission, and admission to an ICU. With nonparenteral exposure, most had no clinical effects or minor effects, and there were no major effects or deaths. With parenteral exposure, moderate effects occurred in 46 (6%), major effects in 2 (0.3%) and there were 4 (0.5%) deaths, two of which were suicides. A dose-response relationship could be demonstrated. Clinical effect durations of up to a week occurred at even the lowest dose range. CONCLUSIONS: Over 250 cases of human tilmicosin exposure are reported to poison centers per year and over 150 of those are parenteral. Most exposures produce no or minor effects, but fatalities have occurred with parenteral exposure. The case fatality rate in parenteral exposures is 10 times the case fatality rate for all human exposures in the AAPCC database. Significant adverse and prolonged effects are reported at parenteral doses > 0.5 mL, suggesting that all parenteral exposures should be referred for healthcare facility evaluation.

Adolescent girls' communication with partners about microbicide use.

BACKGROUND: Topical microbicides could be a female-controlled method of preventing sexually transmissible infections. Despite the possibility of surreptitious use, most women report that they would tell partners, and microbicides may be detectable. The purpose of the present study was to examine communication between adolescent girls and their partners regarding microbicides. METHODS: Girls (aged 14-21 years) participated in a 6-month study in which they were given vaginal moisturisers to use when they had intercourse. Data was collected about their demographics, sexual histories and conversations with mothers and partners. Both quantitative and qualitative analyses were conducted. RESULTS: Girls (n = 171) were asked about conversations with their partners. Talking with mothers and using the product were significantly related to talking with partners. Reasons for not talking were intrapersonal or interpersonal variables, the context of the relationship did not warrant an explanation and the lack of a decision to communicate. There seemed to be no difference in conversations for those who used or did not use. Girls had conversations with their partners when deciding to be in the study, when they were engaged in study activities or when deciding to use the product. Conversations about using the product focused on needing to use the product because of study demands, the lubricating properties or wanting to experience product use. CONCLUSIONS: Most of the girls talked to their partners and had positive conversations. Girls may need help initiating conversations and managing reluctant partners.

Toxic Exposure Surveillance System (TESS)-based characterization of U.S. non-native venomous snake exposures, 1995-2004.

BACKGROUND: Non-native (exotic) snake exposures in the United States have not been systematically characterized. METHODS: The Toxic Exposure Surveillance System (TESS) database of the American Association of Poison Control Centers was analyzed to quantify the number and types, demographic associations, clinical presentations, managements and outcomes, and the health resource utilization of non-native snake exposures. RESULTS: From 1995 through 2004, there were 399 non-native exposures in the TESS database. Of these, 350 snakes (87%) were identified by genus and species, comprising at least 77 different varieties. Roughly equal percentages of snakes originated in Asia, Africa and Latin America, with a smaller number from the Middle-East, Australia, and Europe. Nearly half were viperids and a little more than a third were elapids. The vast majority of exposed individuals were adults. However, almost 15% were aged 17 years or less, and almost 7% were children aged 5 years or younger. Eighty-four percent were males. The vast majority of exposures occurred at the victim's own residence. Over 50% were evaluated at a healthcare facility, with 28.7% admitted to an ICU. Overall, 26% of patients were coded as receiving antivenom treatment. Coded outcomes were similar between viperid and elapid envenomations. There were three deaths, two involving viperid snakes and one elapid. Enhancements to the TESS database are required for better precision in and more complete characterization of non-native snake envenomations.

Adolescents' descriptions of the physical characteristics of microbicide surrogates and experiences of use.

PURPOSE: Our purpose was to describe adolescent girls' perceptions of microbicide surrogates and experiences of use, including impact on sexual pleasure. METHODS: Sexually experienced girls, 14-21 years, were recruited for a study examining microbicide acceptability. The girls were given vaginal moisturizers (gel or suppository) to use as if they were microbicides. Girls (n = 175) discussed their perceptions and experiences of use of these products in response to semistructured interviews. Girls were asked at weekly phone interviews about the impact of product use on their and their partners' sexual pleasure. These answers were averaged, and girls were categorized into those for whom the product predominantely made sex feel worse, better less than half the time, or better half the time or more. The relationship of demographics and sexual history to the impact on pleasure was evaluated. RESULTS: Overall, participants were positive about their experience with the products. More girls preferred the gel. Specific concerns about the suppository included the wait period, texture, and messiness of self-insertion. Many liked the lubricating quality of both of the surrogates. Girls discussed messiness, leakage, clumping, and the difficulties in communicating with partners. Over half reported an increase in pleasure most of the time for themselves and their partners. None of the demographic and sexual history predictors were significantly related to impact on pleasure. CONCLUSIONS: Anticipatory guidance should help girls initiate and sustain use. Future research should examine the best way to accomplish counseling about microbicide use with adolescent girls.

A survey of recommendations by gynecologists in Canada regarding oral contraceptive use in the perioperative period.

OBJECTIVE: This survey was conducted to determine the practice patterns of gynecologists in Canada regarding the discontinuation of oral contraceptives before gynecologic surgical procedures. STUDY DESIGN: In May and June of 1997, surveys were sent to all obstetricians and gynecologists on the mailing list of the Society of Obstetricians and Gynaecologists of Canada. RESULTS: Of the 1472 surveys that were sent, 702 of the surveys were completed and returned, for a response rate of 48%. More than 90% of the gynecologists who were surveyed would advise their patients to continue using oral contraceptives before relatively minor surgical procedures and <1% of them would use low-dose heparin before these procedures. Rates of oral contraceptive discontinuation increased as the extent of the surgical intervention increased: Prolonged laparoscopy (39.8%), vaginal repairs and hysterectomy (54.7%), and abdominal hysterectomy or adnexectomy (56.1%). Just over one half of the gynecologists (56.1%) indicated that they would advise discontinuation > or =4 weeks before the surgical procedure, which is the minimum time required for the prothrombotic changes that are associated with oral contraceptive use to return to baseline. Less than 10% of the surgeons indicated that they would use low-dose heparin even when the patient was advised to continue taking oral contraceptives before major surgical procedures. CONCLUSION: The controversy over whether young healthy women should discontinue oral contraceptive use before major surgical procedures that are associated with immobility is reflected by a lack of consensus among gynecologists in Canada.