Meta-análise Cochrane: teicoplanina versus vancomicina para infecções suspeitas ou confirmadas / Cochrane meta-analysis: teicoplanin versus vancomycin for proven or suspected infection

Objective: To compare efficacy and safety of vancomycin versus teicoplanin in patients with proven or suspected infection. Methods: Data Sources: Cochrane Renal Group's Specialized Register, CENTRAL, MEDLINE, EMBASE, nephrology textbooks and review articles. Inclusion criteria: Randomized controlled trials in any language comparing teicoplanin to vancomycin for patients with proven or suspected infection. Data extraction: Two authors independently evaluated methodological quality and extracted data. Study investigators were contacted for unpublished information. A random effect model was used to estimate the pooled risk ratio (RR) with 95% confidence interval (CI). Results: A total of 24 studies (2,610 patients) were included. The drugs had similar rates of clinical cure (RR: 1.03; 95%CI: 0.98-1.08), microbiological cure (RR: 0.98; 95%CI: 0.93-1.03) and mortality (RR: 1.02; 95%CI: 0.79-1.30). Teicoplanin had lower rates of skin rash (RR: 0.57; 95%CI: 0.35-0.92), red man syndrome (RR: 0.21; 95%CI: 0.08-0.59) and total adverse events (RR: 0.73; 95%CI: 0.53-1.00). Teicoplanin reduced the risk of nephrotoxicity (RR: 0.66; 95%CI: 0.48-0.90). This effect was consistent for patients receiving aminoglycosides (RR: 0.51; 95%CI: 0.30-0.88) or having vancomycin doses corrected by serum levels (RR: 0.22; 95%CI: 0.10-0.52). There were no cases of acute kidney injury needing dialysis. Limitations: Studies lacked a standardized definition for nephrotoxicity. Conclusions: Teicoplanin and vancomycin are equally effective; however the incidence of nephrotoxicity and other adverse events was lower with teicoplanin. It may be reasonable to consider teicoplanin for patients at higher risk for acute kidney injury.

Objetivo: Comparar eficácia e toxicidade da teicoplanina e da vancomicina em pacientes com infecção suspeita ou confirmada. Métodos: Fontes de dados: Cochrane Renal Group's Specialized Register, CENTRAL, MEDLINE, EMBASE, livros de referência e artigos de revisão. Critérios de inclusão: Ensaios clínicos controlados randomizados em qualquer idioma, comparando teicoplanina e vancomicina em pacientes com infecção suspeita ou confirmada. Extração de dados: Dois autores avaliaram a qualidade metodológica dos estudos e extraíram os dados de forma independente. Tentou-se obter dados não publicados diretamente com os autores de cada trabalho. Usou-se um modelo de efeito aleatório para estimar a razão de risco (RR) combinada, com um intervalo de confiança (IC) de 95%. Resultados: Foram incluídos 24 estudos (2.610 pacientes). As drogas tiveram taxas semelhantes de cura clínica (RR: 1,03; IC95%: 0,98-1,08), cura microbiológica (RR: 0,98; IC95%: 0,93-1,03) e mortalidade (RR: 1,02; IC95%: 0,79-1,30). A teicoplanina apresentou menores incidências de rash cutâneo (RR: 0,57; IC95%: 0,35-0,92), síndrome do homem vermelho (RR: 0,21; IC95%: 0,08-0,59) e eventos adversos em geral (RR: 0,73; IC95%: 0,53-1,00). A teicoplanina reduziu o risco de nefrotoxicidade (RR: 0,66; IC95%: 0,48-0,90). Esse efeito foi consistente em todos os subgrupos, inclusive aqueles com pacientes recebendo aminoglicosídeos concomitantes (RR: 0,51; IC95%: 0,30-0,88) oucom dosagens de vancomicina corrigidas pelo nível sérico (RR: 0,22; IC95%: 0,10-0,52). Não foi encontrado nenhum caso de injúria renal que necessitasse de diálise. Limitações: Os estudos não seguiram uma definição padrão de nefrotoxicidade. Conclusões: Teicoplanina e vancomicina têm eficácia semelhante; no entanto, o risco de nefrotoxicidade e outros eventos adversos foi menor com teicoplanina. É razoável considerar o uso de teicoplanina para pacientes em risco de desenvolver injúria renal aguda.

Vasodilation increases pulse pressure variation, mimicking hypovolemic status in rabbits

OBJECTIVE: To test the hypothesis that pulse pressure respiratory variation (PPV) amplification, observed in hypovolemia, can also be observed during sodium nitroprusside (SNP)-induced vasodilation. INTRODUCTION: PPV is largely used for early identification of cardiac responsiveness, especially when hypovolemia is suspected. PPV results from respiratory variation in transpulmonary blood flow and reflects the left ventricular preload variations during respiratory cycles. Any factor that decreases left ventricular preload can be associated with PPV amplification, as seen in hypovolemia. METHODS: Ten anesthetized and mechanically ventilated rabbits underwent progressive hypotension by either controlled hemorrhage (Group 1) or intravenous SNP infusion (Group 2). Animals in Group 1 (n = 5) had graded hemorrhage induced at 10 percent steps until 50 percent of the total volume was bled. Mean arterial pressure (MAP) steps were registered and assumed as pressure targets to be reached in Group 2. Group 2 (n = 5) was subjected to a progressive SNP infusion to reach similar pressure targets as those defined in Group 1. Heart rate (HR), systolic pressure variation (SPV) and PPV were measured at each MAP step, and the values were compared between the groups. RESULTS: SPV and PPV were similar between the experimental models in all steps (p > 0.16). SPV increased earlier in Group 2. CONCLUSION: Both pharmacologic vasodilation and graded hemorrhage induced PPV amplification similar to that observed in hypovolemia, reinforcing the idea that amplified arterial pressure variation does not necessarily represent hypovolemic status but rather potential cardiovascular responsiveness to fluid infusion.

Pulse oximetry wave variation as a noninvasive tool to assess volume status in cardiac surgery

OBJECTIVE: To compare variations of plethysmographic wave amplitude (ÃPpleth) and to determine the percent difference between inspiratory and expiratory pulse pressure (ÃPp) cutoff values for volume responsiveness in a homogenous population of postoperative cardiac surgery patients. INTRODUCTION: Intra-thoracic pressure variations interfere with stroke volume variation. Pulse pressure variations through arterial lines during mechanical ventilation have been recommended for the estimation of fluid responsiveness. Pulse oximetry may offer a non-invasive plethysmographic method to evaluate pulse pressure; this may be useful for guiding fluid replacement. METHODS: Controlled, prospective study in cardiac surgery patients under controlled ventilation. Simultaneous digital recordings of arterial pressure and plethysmographic waves were performed. ÃPp, systolic pressure (ÃPs), DPpleth, and systolic component (ÃSpleth) were calculated. A DPp > 13 percent identified fluid-responsive patients. Volume expansion was performed in responsive subjects. Systolic and amplitude components of pressure and plethysmographic waves were compared. RESULTS: In 50 measurements from 43 patients, ÃPp was correlated with (Ppleth (r=0.90, p<0.001), (Ps (r=0.90, p<0.001), and (Spleth (r=0.73, p<0.001). An aArea under ROC curve (AUC) identified the fluid responsiveness thresholds: (Ppleth of 11 percent (AUC = 0.95±0.04), (Ps of 8 percent (AUC=0.93±0.05), and (Spleth of 32 percent (AUC=0.82±0.07). A (Ppleth value > 11 percent predicted (Pp > 13 percent with 100 percent specificity and 91 percent sensitivity. Volume expansion, performed in 20 patients, changed (Pp, (Ppleth, (Ps and (Spleth significantly (p<0.008). CONCLUSIONS: ÃPpleth is well correlated with DPp and constitutes a simple and non-invasive method for assessing fluid responsiveness in patients following cardiac surgery.