Comparação entre o ponto P6 (NEIGUAM), ondansetron e da associação de ambos na prevenção de náuseas e vômitos em cirurgia ortopédica de membros inferiores sob bloqueio subaracnoideo

Pós-graduação em Anestesiologia - FMB

Ricerca di Escherichia coli produttori di verocitotossine e definizione di obiettivi di performance nella produzione primaria di alimenti di origine animale

La presenza di Escherichia coli produttori di verocitotossine (VTEC o STEC) rappresenta una tra le più importanti cause di malattia alimentare attualmente presenti in Europa. La sua presenza negli allevamenti di animali destinati alla produzione di alimenti rappresenta un importante rischio per la salute del consumatore. In conseguenza di comuni contaminazioni che si realizzano nel corso della macellazione, della mungitura i VTEC possono essere presenti nelle carni e nel latte e rappresentano un grave rischio se la preparazione per il consumo o i processi di lavorazione non comportano trattamenti in grado d’inattivarli (es. carni crude o poco cotte, latte non pastorizzato, formaggi freschi a latte crudo). La contaminazione dei campi coltivati conseguente alla dispersione di letame o attraverso acque contaminate può veicolare questi stipiti che sono normalmente albergati nell’intestino di ruminanti (domestici e selvatici) e anche prodotti vegetali consumati crudi, succhi e perfino sementi sono stati implicati in gravi episodi di malattia con gravi manifestazioni enteriche e complicazioni in grado di causare quadri patologici gravi e anche la morte. Stipiti di VTEC patogeni ingeriti con gli alimenti possono causare sintomi gastroenterici, con diarrea acquosa o emorragica (nel 50% dei casi), crampi addominali, febbre lieve e in una percentuale più bassa nausea e vomito. In alcuni casi (circa 5-10%) l’infezione gastroenterica si complica con manifestazioni tossiemiche caratterizzate da Sindrome Emolitico Uremica (SEU o HUS) con anemia emolitica, insufficienza renale grave e coinvolgimento neurologico o con una porpora trombotica trombocitopenica. Il tasso di mortalità dei pazienti che presentano l’infezione da E. coli è inferiore all’1%. I dati forniti dall’ECDC sulle infezioni alimentari nel periodo 2006-2010 hanno evidenziato un trend in leggero aumento del numero di infezioni a partire dal 2007. L’obiettivo degli studi condotti è quello di valutare la prevalenza ed il comportamento dei VTEC per una analisi del rischio più approfondita.

Einfluss einer indirekten pharmazeutischen Betreuung auf klinische und soziale Ergebnisse bei ambulant mit Chemotherapie behandelten Tumorpatienten

Krebspatienten, die eine Chemotherapie erhalten, leiden häufig an schwerwiegenden unerwünschten Arzneimittelwirkungen, wie z.B. Übelkeit und Erbrechen, welche nachweislich durch eine geeignete Supportivmedikation und durch eine direkte pharmazeutische Betreuung gesenkt werden können.rnIn dieser Arbeit wurde in einer prospektiven, nicht-interventionellen multizentrischen Studie untersucht, ob ambulant behandelte Mamma- und Colon-Carcinom-Patienten während der Chemotherapie Vorteile durch eine indirekte pharmazeutische Betreuung (Mitgabe einer schriftlichen Patienteninformation und der Begleitmedikamente) haben. Primäres Ziel der Studie war eine Reduktion von Häufigkeit und Schweregrad ausgewählter UAW, sekundäre Ziele waren die Verbesserung der Lebensqualität, der Patientenzufriedenheit und des Patientenwissens zur Therapie und Begleitmedikation. Die Daten wurden mittels vier verschiedener Patienten-Fragebögen in Form von Telefoninterviews zu drei verschiedenen Zeitpunkten der Chemotherapie erhoben.rnInsgesamt konnten 106 Patienten vom St.-Johannes-Hospital in Dortmund und von der Universitätsmedizin Mainz in die Studie eingeschlossen werden. Die UAW nach Häufigkeit und Schweregrad gemäß CTC konnten durch eine indirekte pharmazeutische Betreuung zu allen drei Zeitpunkten der Datenerfassung z.T. signifikant gesenkt werden. Eine Verbesserung konnte auch bei allen humanistischen Ergebnisparametern (Patientenwissen, Lebensqualität, Patientenzufriedenheit) beobachtet werden. Auf Grund der relativ kleinen, nicht vollständig rekrutierten Kontrollgruppe und den unterschiedlichen Rahmenbedingungen an den teilnehmenden Kliniken, sind weitere vergleichende Untersuchungen erforderlich, um den Nutzen einer indirekten pharmazeutischen Betreuung weiter zu belegen. rn

Ondansetron does not reduce the shivering threshold in healthy volunteers

BACKGROUND: Ondansetron, a serotonin-3 receptor antagonist, reduces postoperative shivering. Drugs that reduce shivering usually impair central thermoregulatory control, and may thus be useful for preventing shivering during induction of therapeutic hypothermia. We determined, therefore, whether ondansetron reduces the major autonomic thermoregulatory response thresholds (triggering core temperatures) in humans. METHODS: Control (placebo) and ondansetron infusions at the target plasma concentration of 250 ng ml(-1) were studied in healthy volunteers on two different days. Each day, skin and core temperatures were increased to provoke sweating; then reduced to elicit peripheral vasoconstriction and shivering. We determined the core-temperature sweating, vasoconstriction and shivering thresholds after compensating for changes in mean-skin temperature. Data were analysed using t-tests and presented as means (sds); P<0.05 was taken as significant. RESULTS: Ondensetron plasma concentrations were 278 (57), 234 (55) and 243 (58) ng ml(-1) at the sweating, vasoconstriction and shivering thresholds, respectively; these corresponded to approximately 50 mg of ondansetron which is approximately 10 times the dose used for postoperative nausea and vomiting. Ondansetron did not change the sweating (control 37.4 (0.4) degrees C, ondansetron 37.6 (0.3) degrees C, P=0.16), vasoconstriction (37.0 (0.5) degrees C vs 37.1 (0.3) degrees C; P=0.70), or shivering threshold (36.3 (0.5) degrees C vs 36.3 (0.6) degrees C; P=0.76). No sedation was observed on either study day. CONCLUSIONS: /b>. Ondansetron appears to have little potential for facilitating induction of therapeutic hypothermia.

Safety of ondansetron loading doses in children with cancer

INTRODUCTION: In highly emetogenic chemotherapy, the recommended dose of the serotonin-receptor antagonist ondansetron (5 mg/m(2) q8h) may be insufficient to prevent chemotherapy-induced nausea and vomiting. In adults, ondansetron-loading doses (OLD) of 32 mg are safe. We aimed to evaluate in children the safety of an OLD of 16 mg/m(2) (top, 24 mg) i.v., followed by two doses of 5 mg/m(2) q8h. MATERIALS AND METHODS: This retrospective single-center study included all pediatric oncology patients having received >/=1 OLD between 2002 and 2005. Adverse events (AE) definitely, probably, or possibly related to OLD were studied, excluding AE not or unlikely related to the OLD. Associations between potential predictors and at least moderate AE were analyzed by mixed logistic regression. RESULTS: Of 167 patients treated with chemotherapy, 37 (22%) received 543 OLD. The most common AE were hypotension, fatigue, injection site reaction, headache, hot flashes/flushes, and dizziness. At least mild AE were described in 139 OLD (26%), at least moderate AE in 23 (4.2%), and severe AE in 5 (0.9%; exact 95% confidence interval [CI], 0.4-2.1). Life-threatening or lethal AE were not observed (0.0%; 0.0-0.6). At least moderate AE were significantly more frequent in female patients (odds ratio [OR] 3.5; 95% CI 1.4-8.8; p = 0.010), after erroneously given second OLD (17.0; 1.9-154; p = 0.012) and higher 24 h cumulative surface corrected dose (1.26 per mg/m(2); 1.06-1.51; p = 0.009). OLD given to infants below 2 years were not associated with more frequent AE. CONCLUSIONS: Ondansetron-loading doses of 16 mg/m(2) (top, 24 mg) i.v. seem to be safe in infants, children, and adolescents.

The Antimalarial Drug Proguanil Is An Antagonist at 5-HT3 Receptors

Proguanil is an antimalarial prodrug that is metabolized to 4-chlorophenyl-1-biguanide (CPB) and the active metabolite cycloguanil (CG). These compounds are structurally related to meta-chlorophenyl biguanide (mCPBG), a 5-hydroxytryptamine 3 (5-HT3) receptor agonist. Here we examine the effects of proguanil and its metabolites on the electrophysiology and ligand-binding properties of human 5-HT3A receptors expressed in Xenopus oocytes and human embryonic kidney 293 cells, respectively. 5-HT3 receptor responses were reversibly inhibited by proguanil, with an IC50 of 1.81 μM. Competitive antagonism was shown by a lack of voltage-dependence, Schild plot (Kb = 1.70 μM), and radioligand competition (Ki = 2.61 μM) with the 5-HT3 receptor antagonist [3H]granisetron. Kinetic measurements (kon = 4.0 × 104 M−1 s−1; koff = 0.23 s−1) were consistent with a simple bimolecular reaction scheme with a Kb of 4.35 μM. The metabolites CG and CPB similarly inhibited 5-HT3 receptors as assessed by IC50 (1.48 and 4.36 μM, respectively), Schild plot (Kb = 2.97 and 11.4 μM), and radioligand competition (Ki = 4.89 and 0.41 μM). At higher concentrations, CPB was a partial agonist (EC50 = 14.1 μM; I/Imax = 0.013). These results demonstrate that proguanil competitively inhibits 5-HT3 receptors, with an IC50 that exceeds whole-blood concentrations following its oral administration. They may therefore be responsible for the occasional gastrointestinal side effects, nausea, and vomiting reported following its use. Clinical development of related compounds should therefore consider effects at 5-HT3 receptors as an early indication of possible unwanted gastrointestinal side effects.

Hiperparatiroidismo primário em doentes jovens

Trabalho Final do Curso de Mestrado Integrado em Medicina, Faculdade de Medicina, Universidade de Lisboa, 2014

An analysis of clinical characteristics in genetically linked migraine-affected pedigrees

Migraine is a common complex disorder characterized by severe recurrent headache and usually accompanied by nausea and vomiting. Previous studies in our laboratory have utilized three large multigenerational Australian pedigrees affected with migraine to indicate that the disease is genetically heterogeneous, with linkage results implicating genomic susceptibility regions on both chromosomes 19p and Xq. The present study explores the possibility of a correlation between genetic and clinical heterogeneity in these affected pedigrees. Specifically, the clinical characteristics of migraine including subtype, age of onset, frequency, duration, and disease symptoms were compared between the migraine pedigrees, and gender differences were also assessed. Our exploratory analyses revealed no significant differences in any of the clinical characteristics tested between the chromosome 19-linked family and the two X-linked families. Also, we did not detect any differences in male vs. female clinical features for these pedigrees. In conclusion, migraine is considered to be a clinically and genetically heterogeneous disorder; however, our study provided no conclusive evidence that variation in genomic susceptibility region is related to heterogeneity at the clinical level in these migraine-affected pedigrees.

The role of morphine-6-glucuronide (M6G) in pain control

Morphine-6beta-D-glucuronide (M6G) is an analgesically active metabolite of morphine, accounting for approximate to10% of the morphine dose when administered by systemic routes to humans. Although M6G is more hydrophilic than morphine, it crosses the blood-brain barrier, albeit relatively slowly. For this reason, it is generally thought that, after chronic dosing, M6G contributes significantly to the analgesic effects of systemically administered morphine. Owing to its polar nature, M6G is cleared from the systemic circulation primarily via renal elimination. As M6G accumulates in patients with renal impairment, there is an increased risk of M6G-induced respiratory depression in renal failure patients who are being dosed chronically with systemic morphine. Consistent with its analgesic and respiratory depressant properties, M6G binds to the p-opioid receptor in a naloxone-reversible manner. Although the affinity of M6G for the mu-opioid receptor is similar to or slightly less than that of morphine, preclinical studies in rodents show that M6G is one to two orders of magnitude more potent than morphine when administered by central routes. This major discrepancy between the markedly higher intrinsic antinociceptive potency of M6G relative to morphine, despite their similar p-opioid receptor binding affinities, is difficult to reconcile. It has been proposed that M6G mediates its pain-relieving effects through a novel 'M6G opioid receptor', while others have argued that M6G may have higher efficacy than morphine for transduction of intracellular events. When administered by parenteral routes to rodents, M6G's antinociceptive potency is no more than twofold higher than morphine. In humans, the analgesic efficacy and respiratory depressant potency of M6G relative to morphine have been assessed in a number of short-term studies involving the intrathecal or intravenous routes of administration. For example, in hip replacement patients, intrathecal M6G provided excellent postoperative analgesia but the occurrence of late respiratory depression in 10% of these patients raised serious concern about safety. In postoperative patients, intravenous M6G administered by means of patient-controlled analgesia (PCA), or bolus plus PCA, produced no analgesia in one study and limited analgesia in another. Similarly, there was a lack of significant analgesia in healthy volunteers who received intravenous M6G for the alleviation of experimental pain (carbon dioxide applied to the nasal mucosa). In contrast, satisfactory analgesia was produced by bolus doses of intravenous M6G administered to patients with cancer pain, and to healthy volunteers with experimentally-induced ischaemic, electrical or thermal (ice water) pain. Studies to date in healthy volunteers suggest that intravenous M6G may be a less potent respiratory depressant and have a lower propensity for producing nausea and vomiting than morphine. However, it is unclear whether equi-analgesic doses of M6G and morphine were compared. Clearly, more extensive short-term trials, together with studies involving chronic M6G administration, are necessary before the potential clinical utility of M6G as an analgesic drug in its own right can be determined.

Hyperemesis gravidarum: current perspectives.

Hyperemesis gravidarum is a complex condition with a multifactorial etiology characterized by severe intractable nausea and vomiting. Despite a high prevalence, studies exploring underlying etiology and treatments are limited. We performed a literature review, focusing on articles published over the last 10 years, to examine current perspectives and recent developments in hyperemesis gravidarum.

Motion Sickness

Over 2000 years ago the Greek physician Hippocrates wrote, “sailing on the sea proves that motion disorders the body.” Indeed, the word “nausea” derives from the Greek root word naus, hence “nautical,” meaning a ship. The primary signs and symptoms of motion sickness are nausea and vomiting. Motion sickness can be provoked by a wide variety of transport environments, including land, sea, air, and space. The recent introduction of new visual technologies may expose more of the population to visually induced motion sickness. This chapter describes the signs and symptoms of motion sickness and different types of provocative stimuli. The “how” of motion sickness (i.e., the mechanism) is generally accepted to involve sensory conflict, for which the evidence is reviewed. New observations concern the identification of putative “sensory conflict” neurons and the underlying brain mechanisms. But what reason or purpose does motion sickness serve, if any? This is the “why” of motion sickness, which is analyzed from both evolutionary and nonfunctional maladaptive theoretic perspectives. Individual differences in susceptibility are great in the normal population and predictors are reviewed. Motion sickness susceptibility also varies dramatically between special groups of patients, including those with different types of vestibular disease and in migraineurs. Finally, the efficacy and relative advantages and disadvantages of various behavioral and pharmacologic countermeasures are evaluated.

Does the nasogastric tube has a role in elective colo-rectal surgery?

Introduction. Routine use of nasogastric tubes (NGT) after abdominal operations is intended to hasten the return of bowel function, diminish the risk of anastomotic leakage and prevent pulmonary complications. The aim of our study was to prospectively assess the tolerability and the safety of the non use of NGT after elective colorectal open operations. Patients and methods. Between March 2009 and December 2010, 110 consecutive patients underwent colo-rectal elective open surgery for neoplasm without nasogastric decompression. We analyzed the incidence of nausea and vomiting, the pulmonary complications, the return of bowel function the deep wound breakdown (fascial dehiscence) and the anastomotic leakage. Results. Only 15 patients (13,6%) reported nausea without vomiting immediately after surgery and 9 cases of vomiting were observed (8%), requiring the insertion of the NGT (nasogastric tube) in 5 (4,5%). A total of 105 patients (96,3%) were NGT free. No deep wound dehiscence was observed and only one real pneumonia occurred. Anastomotic dehiscence occured in 4 patients (3,6%) and a second surgical procedure was needed in three cases. The return of bowel function, except in the last four patients, occurred in 3,8 days average (range 2-7 days). Conclusion. We confirm the uselessness of the NGT in the framework of fast track program adopted in elective open colo-rectal surgery.

Iniltration vs. instillation of ropivacaine 7.5% in radical mastectomies for postoperative analgesia

Objective: Determining the effectiveness of iniltration versus instillation with 7.5% ropivacaine in reducing the intensity of postoperative pain in patients undergoing a radical mastectomy. Material and methods: Clinical, prospective, and comparative analytical study in a sample of 20 female patients between 20 and 60 years of age, ASA I and II, weight 50-90 kg, who were divided into 2 groups (10 patients each). In Group 1 infiltration with ropivacaine 7.5% (20 ml) was applied prior to closure of the surgical wound, meanwhile in Group 2 ropivacaine 7.5% (20 ml), was instilled into the surgical wound. P ain intensity was assessed by a visual analog scale (V AS) upon extubation. The need for rescue medication and the incidence of nausea and vomiting were measured from 0 to 30 minutes postoperatively and at 2, 4, 8 and 12 hours. Results: There was no statistical difference between the groups (only the group managed through iniltration required rescue medications), but the iniltration group had a lower perception of pain. Conclusions: This study reported the same eficacy of preventive treatment of postoperative pain in patients who underwent radical mastectomy for instillation and iniltration with 7.5% ropivacaine and little need for rescue medication postoperatively.

Outcomes of Second Look Exploration in Testicular Torsion of Children

Background: Testicular torsion (TT), or twisting of the testicle resulting in a strangulation of the blood supply, occurs in men whose tissue surrounding the testicle is not well attached to the scrotum. It is important to emphasize that testicular torsion is a medical emergency. Objectives: The aim of this study is to evaluate the second look exploration and outcomes in TT. Patients and Methods: Seventy boys out of 124 patients underwent early exploration and 48 hours later second look exploration due to TT. All patients were checked with preoperative color-doppler ultrasonography (CDU) and intraoperative bleeding test. Data included age at admission, side of pathology, relation of TT with season of year, duration of preoperative history, degree of testicular torsion, CDU findings, and degree of bleeding; results of second look exploration, follow-up, and outcomes were analyzed. Results: Totally 70 patients were included in this study within five years, of which mean age was 28.6 ± 32.9 months (range 1 to 144), 48% of our patients had nausea and vomiting. Preoperative CDU showed absent/weak flow in 50 (71%) cases. Winter showed most frequently (44%) referred cases of testicular torsion. Orchidopexy was performed in 44 (63%) and orchidectomy in 26 (37%) cases after second look exploration. Mean follow-up duration was 3.1 ± 1.4 years. 4 (9%) cases in orchidopexy group developed testicular atrophy during follow-up, all four cases had a history of longer than 12 hours and grade II testicular bleeding test intra-operatively. Other orchidopexy patients salvaged. 26 patients, who were in grade III, underwent orchidectomy in second look exploration. Conclusions: TT requires emergency attention. The ischemia time of the testis is traditionally after 6 hours, and imaging or other diagnostic modality should not be a cause of delay. Early surgical exploration is modality of choice, and second look exploration after 48 hours can be more effective and salvageable in these patients.

Randomized controlled trial on single dose steroid before thyroidectomy for benign disease to improve postoperative nausea, pain, and vocal function

OBJECTIVE: To evaluate the effects of a single preoperative dose of steroid on thyroidectomy outcomes. BACKGROUND: Nausea, pain, and voice alteration frequently occur after thyroidectomy. Because steroids effectively reduce nausea and inflammation, a preoperative administration of steroids could improve these thyroidectomy outcomes. METHODS: Seventy-two patients (men = 20, women = 52) undergoing thyroidectomy for benign disease were included in this randomized, controlled, 2 armed (group D: 8 mg dexamethasone, n = 37; group C: 0.9% NaCl, n = 35), double-blinded study (clinical trial number NCT00619086). Anesthesia, surgical procedures, antiemetics, and analgesic treatments were standardized. Nausea (0-3), pain (visual analog scale), antiemetic and analgesic requirements, and digital voice recording were documented before and 4, 8, 16, 24, 36, and 48 hours after surgery. Patients were followed-up 30 days after hospital discharge. RESULTS: Baseline characteristics were similar among the 2 treatment groups. Nausea was pronounced in the first 16 hours postoperatively (scores were <0.3 and 0.8-1.0 for group D and C, respectively (P = 0.005)), and was significantly lower in group D compared with group C during the observation period (P = 0.001). Pain diminished within 48 hours after surgery (visual analog scale 20 and 35 in group D and C, respectively (P = 0.009)). Antiemetic and analgesic requirements were also significantly diminished. Changes in voice mean frequency were less prominent in the dexamethasone group compared with the placebo group (P = 0.015). No steroid-related complications occurred. CONCLUSION: A preoperative single dose of steroid significantly reduced nausea, vomiting, and pain, and improved postoperative voice function within the first 48 hours (most pronounced within 16 hours) after thyroid resection; this strategy should be routinely applied in thyroidectomies.