Volatile anaesthetics may be the main cause of early but not delayed postoperative vomiting: a randomized controlled trial of factorial design

Background. Despite intensive research, the main causes of postoperativenausea and vomiting (PONV) remain unclear. We sought to quantifythe relative importance of operative, anaesthetic and patient-specificrisk factors to the development of PONV. Methods. We conducted a randomized controlled trial of 1180children and adults at high risk for PONV scheduled for electivesurgery. Using a five-way factorial design, we randomly assignedsubjects by gender who were undergoing specific operative procedures,to receive various combinations of anaesthetics, opioids, andprophylactic antiemetics. Results. Of the 1180 patients, 355 (30.1% 95% CI (27.5–32.7%))had at least one episode of postoperative vomiting (PV) within24 h post-anaesthesia. In the early postoperative period (0–2h), the leading risk factor for vomiting was the use of volatileanaesthetics, with similar odds ratios (OR (95% CI)) being foundfor isoflurane (19.8 (7.7–51.2)), enflurane (16.1 (6.2–41.8))and sevoflurane (14.5 (5.6–37.4)). A dose–responserelationship was present for the use of volatile anaesthetics.In contrast, no dose response existed for propofol anaesthesia.In the delayed postoperative period (2–24 h), the mainpredictors were being a child (5.7 (3.0–10.9)), PONV inthe early period (3.4 (2.4–4.7)) and the use of postoperativeopioids (2.5 (1.7–3.7)). The influence of the antiemeticswas considerably smaller and did not interact with anaestheticor surgical variables. Conclusion. Volatile anaesthetics were the leading cause ofearly postoperative vomiting. The pro-emetic effect was largerthan other risk factors. In patients at high risk for PONV,it would therefore make better sense to avoid inhalational anaesthesiarather than simply to add an antiemetic, which may still beneeded to prevent or treat delayed vomiting. Br J Anaesth 2002; 88: 659–68     

Effect of variable hydraulic conductivity on transcapillary fluid exchange: Application to the microcirculation of rat intestinal muscle

A theoretical model has been developed to study the influence of variable hydraulic wall conductivity of single capillaries on transmural fluid exchange. A systematic study has been carried out to examine the factors which determine the direction of transcapillary fluid flow; i.e., filtration or absorption. One important result of this study is that, in addition to capillary pressure and plasma protein concentration, the shape of the axial distribution of the hydraulic conductivity of the capillary wall can affect the direction of transmural fluid movement. The experimental data for the axial distribution of the hydraulic conductivity of single capillaries in the rat intestinal muscle of R. W. Gore, W. Schoknecht, and H. G. Bohlen (In “Microcirculation,” J. Grayson and W. Zingg, eds., Vol. 1, pp. 331–332, Plenum, New York) were employed in the present model in order to predict axial and radial fluid flow. The comparison of the results with experimental data for capillary pressure and transmural flux at four axial positions showed excellent agreement. The results of the present model support the experimental finding of Gore et al. that the capillary bed in the rat intestinal muscle is absorptive.     

Human papillomavirus prevalence at the USA-Mexico border among women 40 years of age and older

The incidence of cervical cancer increases with age among USA Hispanics and women living in Latin America starting in the fourth decade of life. We conducted a study of women > or = 40 living at the USA-Mexico border to determine the prevalence and risk factors for human papillomavirus (HPV) infection detected by polymerase chain reaction. In all, 9.2% of participants tested HPV positive. Compared with women aged 50-59, odds ratios of 8.82 and 6.67 were observed for women > or = 60 and 40-49, respectively. Among women aged 40-49, both oncogenic and non-oncogenic HPV infections were detected; however, women > or = 60 were positive for predominantly oncogenic genotypes. HPV risk significantly increased with > or = 2 lifetime sexual partners in adjusted models. These data suggest that the prevalence of HPV infection may have a second peak among post-menopausal Hispanic women.     

Epidural haematoma after evacuation of contralateral subdural haematoma

Background Sequentially evolving intracranial bilateral haematomas, where the second haematoma develops after the surgical removal of the first one is rarely reported. Aim To report a patient who developed an epidural haematoma after evacuation of a contralateral subdural haematoma. Methods A 49-year-old male was admitted to our department after head injury. A brain computerized tomography (CT) scan revealed an acute subdural haematoma in the right temporal area which was evacuated. During his stay in the intensive care unit, he was submitted to intracranial pressure monitoring, which soon rose. Results A new CT scan showed an acute epidural haematoma in the contralateral parietal area that was also evacuated. Conclusions While rising intracranial pressure after the evacuation of a traumatic haematoma is usually attributed to brain oedema or recurrent haematoma at the craniotomy site, the development of a contralateral epidural haematoma requiring surgical treatment should not be overlooked.     

Ethnic variation of the P53 codon 72 polymorphism, HPV persistence, and cervical cancer risk

Association between the p53 codon 72 polymorphism and cervical cancer remains unresolved. We determined the association between the polymorphism and risk of human papillomavirus (HPV) persistence. The polymorphism was detected by restriction enzyme digestion following p53 amplification and HPV detection by the PGMY 09/11 primer set followed by reverse line blot hybridization: 3371 samples were analysed. HPV persistence was assessed on a subset of samples collected at baseline, four and 10 months (n =442). Highly significant differences were observed between ethnic groups (P <0.005). No associations were found between P53 arginine and cytological grade in women infected with any HPV or any oncogenic HPV, despite adjustment for ethnicity. These results were sustained even when HPV-negative women were used as controls. Persistence for any or oncogenic HPV infection was not associated with the polymorphism, irrespective or ethnicity adjustment. Our findings do not support a role for this polymorphism conferring elevated risk for HPV-related disease.     

Healthcare Access and Utilization Among Women 40 and Older at the U.S.-Mexico Border: Predictors of a Routine Check-Up

Mexican Americans are more likely to experience barriers to access and utilization of healthcare services than any other U.S. Hispanic group. In Mexico, where the majority of the population has access to care, the pressing issue is the underutilization of preventive services among adults. This study was conducted to assess access and utilization barriers among a U.S.-Mexico border population. A cross-sectional, population-based survey was conducted during 1999–2000 in a pair of contiguous U.S.-Mexico border communities. Household surveys were administered to U.S. and Mexican women, 40 years of age and older, to assess healthcare access and utilization, participation in chronic disease screenings, orientation toward prevention and personal history of chronic disease. Analysis indicates few statistically significant differences (p < 0.05) among access and utilization variables by country. Mexican participants were more likely to have a regular source of care and to have had a blood sugar test within the past 12 months. U.S. participants more often reported having had a Pap smear and mammogram during the previous year. Factors independently positively associated with having had a routine check-up during the past 12 months included age and having a regular provider or place to go when sick. Only going to the doctor when ill was independently inversely associated with routine check-ups in the past 12 months. Findings suggest that U.S. and Mexican border populations are similar with regard to healthcare access and utilization characteristics. Efforts to increase utilization of preventive health screenings among women are needed at the U.S.-Mexico border.     

The double puncture: an effective percutaneous technique for removing complex, multiple renal calculi

Percutaneous nephrostolithotomy, which can require a double puncture, is presently the method of choice in our institution for the removal of renal stones. Patients that underwent this procedure were evaluated to identify the possible reasons for the double puncture. Of 200 patients evaluated, 14 needed a second tract. The three variables that determined whether a second puncture was needed, in order of importance, were number and size of the stones, with second tracts needed in patients with multiple stones and staghorn calculi; anatomical variations of the renal collecting system itself, with bifid systems the most significant anatomic variation; and the dexterity of the radiologist in performing the puncture and the ability of the urologist to extract the stone. Second tracts were needed more frequently in patients who presented with stones in both the lower and middle poles of the collecting systems.