RESUMEN
Ondansetron is widely believed to prevent postoperative vomiting more effectively than nausea. We analysed data from 5161 patients undergoing general anaesthesia who were randomly stratified to receive a combination of six interventions, one of which was 4 mg ondansetron vs placebo. For the purpose of this study a 20% difference in the relative risks for the two outcomes was considered clinically relevant. Nausea was reduced from 38% (969/2585) in the control to 28% (715/2576) in the ondansetron group, corresponding to a relative risk of 0.74, or a relative risk reduction of 26%. Vomiting was reduced from 17% (441/2585) to 11% (293/2576), corresponding to a relative risk of 0.67, or a relative risk reduction of 33%. The relative risks of 0.67 and 0.74 were clinically similar and the difference between them did not reach statistical significance. We thus conclude that ondansetron prevents postoperative nausea and postoperative vomiting equally well.
Asunto(s)
Antieméticos/uso terapéutico , Ondansetrón/uso terapéutico , Náusea y Vómito Posoperatorios/prevención & control , Adulto , Anestesia General , Femenino , Humanos , Masculino , Persona de Mediana Edad , Náusea y Vómito Posoperatorios/etiología , Periodo Posoperatorio , Factores de RiesgoRESUMEN
BACKGROUND: Untreated, one third of patients who undergo surgery will have postoperative nausea and vomiting. Although many trials have been conducted, the relative benefits of prophylactic antiemetic interventions given alone or in combination remain unknown. METHODS: In a randomized, controlled trial of factorial design, 5,199 patients at high risk for postoperative nausea and vomiting were randomly assigned to 1 of 64 possible combinations of 6 prophylactic interventions: 1) 4 mg of ondansetron or no ondansetron; 2) 4 mg of dexamethasone or no dexamethasone; 3) 1.25 mg of droperidol or no droperidol; 4) propofol or a volatile anesthetic; 5) nitrogen or nitrous oxide; 6) remifentanil or fentanyl. The primary aim parameter was nausea and vomiting within 24 h after surgery, which was evaluated blindly. RESULTS: Ondansetron, dexamethasone, and droperidol each reduced the risk of postoperative nausea and vomiting by about 26%, propofol reduced the risk by 19%, and nitrogen by 12%. The risk reduction with both of these agents (i.e., total intravenous anesthesia) was thus similar to that observed with each of the antiemetics alone. All the interventions acted independently of each other and independently of the patients' baseline risk. Consequently, the relative risks associated with the combined interventions could be estimated by multiplying the relative risks associated with each intervention. However, absolute risk reduction was a critical function of patients' baseline risk. CONCLUSIONS: Because antiemetic interventions are similarly effective and act independently, the safest or least expensive should be used first. Prophylaxis is rarely warranted in low-risk patients, moderate-risk patients may benefit from a single intervention, and multiple interventions should be reserved for high-risk patients.
Asunto(s)
Antieméticos/uso terapéutico , Náusea y Vómito Posoperatorios/tratamiento farmacológico , Analgésicos Opioides/efectos adversos , Anestésicos por Inhalación/efectos adversos , Anestésicos Intravenosos/efectos adversos , Antieméticos/economía , Protocolos Clínicos , Dexametasona/uso terapéutico , Droperidol/uso terapéutico , Quimioterapia Combinada , Femenino , Fentanilo/efectos adversos , Humanos , Masculino , Oportunidad Relativa , Ondansetrón/uso terapéutico , Piperidinas/efectos adversos , Náusea y Vómito Posoperatorios/economía , Náusea y Vómito Posoperatorios/prevención & control , Propofol/efectos adversos , Remifentanilo , Proyectos de Investigación , RiesgoRESUMEN
A study of 320 samples of mammary quarters from cows in 40 dairy farms around Santa Fe city during 1977-1978 was made. The samples were selected based on clinical examination and California Mastitis Test (GMT). High percentage of subclinical mastitis was found. The etiological agents most frequently isolated were Staphylococcus aureus (54,1%), Streptococcus agalactiae (23.4%) and Pseudomonas aeruginosa (13,2%). A winter increment of S. aureus (48,1%) and P. aeruginosa (3,7% and 22,5%) was observed. But S. agalactiae did not experiment considerable variation (26,8% and 20% throughout the year. The sensitivity to antibiotics of some strains decreased in winter specially in S. aureus and P. aeruginosa (61,5% and 38,9%), and some biochemical properties related with their virulence increased. Penicillin in milk was not detected, but the levels of contamination by non specific inhibitory substances were very high (40%). Besides it was found a great contamination with aerobic sporeforming bacteria in these samples, being Bacillus coagulans (59,1%), B. polymyxa (26,1%) and B. sphaericus (9,5%) the most frequent.
Asunto(s)
Mastitis Bovina/microbiología , Pseudomonas aeruginosa/aislamiento & purificación , Staphylococcus aureus/aislamiento & purificación , Streptococcus agalactiae/aislamiento & purificación , Animales , Antibacterianos/farmacología , Bovinos , Farmacorresistencia Microbiana , Femenino , Leche/microbiologíaRESUMEN
A study of 320 samples of mammary quarters from cows in 40 dairy farms around Santa Fe city during 1977-1978 was made. The samples were selected based on clinical examination and California Mastitis Test (GMT). High percentage of subclinical mastitis was found. The etiological agents most frequently isolated were Staphylococcus aureus (54,1
) and Pseudomonas aeruginosa (13,2
). A winter increment of S. aureus (48,1
) and P. aeruginosa (3,7
throughout the year. The sensitivity to antibiotics of some strains decreased in winter specially in S. aureus and P. aeruginosa (61,5
), and some biochemical properties related with their virulence increased. Penicillin in milk was not detected, but the levels of contamination by non specific inhibitory substances were very high (40
). Besides it was found a great contamination with aerobic sporeforming bacteria in these samples, being Bacillus coagulans (59,1
) and B. sphaericus (9,5
) the most frequent.
RESUMEN
A study of 320 samples of mammary quarters from cows in 40 dairy farms around Santa Fe city during 1977-1978 was made. The samples were selected based on clinical examination and California Mastitis Test (GMT). High percentage of subclinical mastitis was found. The etiological agents most frequently isolated were Staphylococcus aureus (54,1
), Streptococcus agalactiae (23.4
) and Pseudomonas aeruginosa (13,2
). A winter increment of S. aureus (48,1
) and P. aeruginosa (3,7
and 22,5
) was observed. But S. agalactiae did not experiment considerable variation (26,8
and 20
throughout the year. The sensitivity to antibiotics of some strains decreased in winter specially in S. aureus and P. aeruginosa (61,5
and 38,9
), and some biochemical properties related with their virulence increased. Penicillin in milk was not detected, but the levels of contamination by non specific inhibitory substances were very high (40
). Besides it was found a great contamination with aerobic sporeforming bacteria in these samples, being Bacillus coagulans (59,1
), B. polymyxa (26,1
) and B. sphaericus (9,5
) the most frequent.