Antibiotic prophylaxis in sever Acute Panceriatitis
Antibiotic prophylaxis is not protective in severe acute<br />pancreatitis: a systematic review and meta-analysis<br />Dr Mohammed Al-Shehri<br />KFHU – Khobar<br />General Surgery<br />2010<br />
Definition<br />It is an inflammatory disorder of previously normal pancreas. Typically cause pain and interfere with the exocrine function of the gland. <br />Cause local, adjacent and remote organs involvement.<br />
The American Journal of Surgery (May 2009) 197, 806-813<br />Review<br />Antibiotic prophylaxis is not protective in severe acute<br />pancreatitis: a systematic review and meta-analysis<br />Nadim S. Jafri, M.D., M.Sc.a,b, Suhal S. Mahid, M.D., Ph.D.c, Spencer R. Idsteinc,<br />Carlton A. Hornung, Ph.D., M.P.H.a,b, Susan Galandiuk, M.D.c,*<br />aDivision of Internal Medicine, Department of Medicine, bDepartment of Epidemiology and Population Health, cPrice<br />Institute of Surgical Research and the Section of Colorectal Surgery, Department of Surgery, University of Louisville,<br />School of Medicine, Louisville, KY 40292, USA<br />
SAP usually develops when part of the pancreas become necrotic and many complications are associated with the presence of this dead pancreatic tissue.
It requires intensive and aggressive management.
International symposium on AP described SAP as being associated organ failure and/or local complications such as abscess ,necrosis, or pseudocyst.</li></li></ul><li>Cont….<br /><ul><li>SAP is diagnosed if any of the following 4 criteria are met:</li></ul> organ failure with 1 or more of the following:<br />shock (SBP < 90mmHg).<br />Pulmonary insufficiency(PaO2<60).<br />Renal failure (creatinine>2mg /dL after rehydration).<br />GIT bleeding ( >500 ml in 24 hrs ) .<br /> local complications such as necrosis, abscess or pseudo cyst.<br />at least 3 of Ranson criteria.<br />
Cont….<br />at least 8 of APACHE II criteria.<br /><ul><li>mortality in SAP ranging from 10% -25% .
The disease process comprises 2 stage :</li></ul>the initial phase is characterized by SIRS that can lead to multi-organ failure and ultimately death.<br />The later phase compromises secondary bacterial infection of devitalized tissues primarily caused by gut organism.<br /><ul><li>These invading organism involving aerobic and anaerobic bacteria.
Sterile necrosis can be infected with gut bacteria in up to 70% .</li></li></ul><li>Cont…..<br />AIM<br /><ul><li>To assess the clinical out come of pts with SAP treated with prophylactic antibiotics with that of pts not treated with antibiotics.
Hypothesis.</li></li></ul><li>Method<br />STUDY SELECTION<br /><ul><li>MEDLNE ,EMBASE(1966-May2008) and the Cochrane Central Register of Controlled Trials, using PubMed and Ovid as search engines, in addition to Google Scholar.
Limited to the human studies without language restrictions.
Hand –searched the references of review articles , evaluated symposia proceeding, poster presentations and abstracts from major gastrointestinal and surgical meetings. </li></li></ul><li>Cont…..<br />INCLUSION CITERIA<br /><ul><li>all studies were RCTs .
SAP was diagnosed with contrast enhanced CT scan and any of the following : APACHE II, Imrie classification and increased C-reactive protein levels > 120 mg /Dl.
If there were multiple publications of the same trail, only the most recent publication was considered for analysis. </li></li></ul><li>Cont…<br />EXCLUSION CRITERIA<br /><ul><li>Case repots, letters, editorials , comments, reviews and abstracts with insufficient data.
Each articles scrutinized to meet the criteria.
Data abstracted independently by each reviewer using a standardized data collection to increase the uniformity of data and to reduce the reporting bias.
In discrepancy , a consensus decision was made with the help of the senior author.</li></li></ul><li>Cont…<br /><ul><li>The following data were abstracted form each report:
first author, year of publication, institution, single/multicenter study, number of pt in the treatment and controlled arms, etiologies, length of follow up period, name of antibiotics , dose and timing of antibiotics administration, incidence of non pancreatic infection, incidence of surgery, incidence of mortality , method of data analysis and the method of diagnosing complications. </li></li></ul><li>Cont…<br />ASSESSMENT OF STUDY QUALITY<br /><ul><li>5 –question scale :</li></ul> The study is randomized.<br />The study is double –blinded.<br />Withdrawals are described.<br />Randomization allocation is explained adequately.<br />Blindness is described adequately.<br /><ul><li>Score ranging from 1 to 5 .
3 or more high quality, used as part of the sensitivity analysis.</li></li></ul><li>Cont….<br />STATISTIACL ANALYSIS<br /><ul><li> Meta- analysis performed according to the quality of reporting meta-analysis guidelines.
The effect measures estimated were relative risk (RR) for dichotomous data, which we report with 95% confidence intervals (CIs).
The RR indicates the risk of an individual who received prophylactic antibiotics developing a wound infection compared with the risk of an individual not receiving prophylactic antibiotics.
Relative risk reduction (RRR), absolute risk reduction (ARR), and number needed to treat (NNT) were calculated to assess if the relative risk was clinically important.</li></li></ul><li>Result<br />STUDY CHARACTERISTICS<br />
Cont….<br />PATIENTS AND ANTIBIOTCS TREATMENT<br /><ul><li>Total of 502 pts .
A total of 253 pts were randomized to the antibiotic prophylaxis group and 249 were randomized to the placebo arm.
60 % alcoholic , 24% biliary , and 20 % other causes.
Duration of antibiotics treatment ranged from 5 to 21 days .
Hospital stay ranged from 18 to 95 days .</li></li></ul><li>
Cont…<br />Crude outcome rates are presented in Table 2. By using<br />a fixed-effect model to evaluate mortality, antibiotic prophylaxis<br />resulted in a RR of .76 (95% CI, .49 –1.16; I2 8.8%; indicating homogeneity among studies)<br />
Cont….<br />SENSITIVITY ANALYSIS<br />Sensitivity analysis was conducted to determine whether infected necrosis, surgical interventions, nonpancreatic infections, class of antibiotic, or study quality (Jadad et al16<br /> scale 3) had a significant effect on the strength and direction of the results. <br />
Cont…<br /><ul><li>Infected necrosis:</li></ul>7 studies evaluated infected necrosis in pts<br /> ( n=429; antibiotics , 43 0f 217; placebo,53 0f 212 ) and found no benefit of antibiotics.<br /><ul><li>Surgical interventions:</li></ul>Seven studies evaluated the need for surgical intervention in SAP (n 476; antibiotics, 55 of 240; placebo, 60 of 236) and collectively did not find a beneficial effect of antibiotics .<br />
Cont…..<br /><ul><li>Nonpancreatic infections:</li></ul>Six studies reported patients who had nonpancreatic infections in both study groups (n 407; antibiotics, 45 of 206; placebo, 71 of 201).<br />There was a pooled benefit associated with antibiotic use (RR, .60; 95% CI, .44 –.82; I2 50.1) with a RRR of 40% (95% CI, 18%–56%; I2 50.1%), an ARR of 15% (95% CI, 6%–23%), and a NNT of 7 (95% CI, 4–17). <br />
Cont….<br />TYPE OF ANTIBIOTICS<br /><ul><li>β LACTAM:4 studies .</li></ul>Mortality.<br />Four studies that used only B-lactams and evaluated mortality (n= 305; antibiotics, 18 of 152; placebo, 22 of 153) found no benefit to the use of prophylactic antibiotics.<br />Infected necrosis.<br />Studies that used B-lactams and evaluated infected necrosis (n= 232; antibiotics, 15 of 116; placebo, 22 of 116) found no benefit to the use of prophylactic antibiotics.<br />
Cont…<br />Surgicalinterventions. <br />Four studies that used B–lactams and evaluated surgical intervention (n=305; antibiotics, 30<br />of 152; placebo, 29 of 153) found no beneficial <br />effect.<br />Nonpancreaticinfections. <br />Four studies that used B-lactams and evaluated nonpancreatic infections (n = 305; antibiotics, 29 of 152; placebo, 53 of 153) found a beneficial effect.<br />
Cont…<br /><ul><li>Higher-quality studies.</li></ul>Five studies scored higher than 3 on the Jadad et al scale and thus were considered of high quality.<br />Mortality.<br /> All 5 studies evaluated mortality in SAP (n= 367; antibiotics, 19 of 182; placebo, 29 of 185) and found no benefit of prophylactic antibiotics.<br />Infectednecrosis. <br />Four studies evaluated infected necrosis in SAP (n 294; antibiotics, 26 of 146; placebo, 29 of 148) and found no benefit of prophylactic antibiotics.<br />
Cont…<br />Surgicalintervention. <br />All 5 studies evaluated surgical intervention in SAP (n 367; antibiotics, 35 of 182; placebo, 38 of 185) and found no benefit of prophylactic antibiotics (RR, .91; 95% CI, .61–1.38; I2 16.5).<br />Nonpancreaticinfections.<br /> Four studies evaluated nonpancreatic infections in SAP (n 307; antibiotics, 35 of 152; placebo, 49 of 155) and found no benefit of prophylactic<br /> antibiotics.<br />
Funnel plot of high-quality studies (Jadad et al16 score <br />3). The vertical axis represents the line of no effect with the horizontal<br />axis representing log of RR. The 95% CI is represented by the<br />diagonal lines. The circles represent each study<br />
Meta-analysis of RCTs on prophylactic antibiotics versus placebo/no intervention on mortality.<br />
Conclusion<br />The role of systemic antibiotics in the management of acute pancreatitis remains controversial.<br />The development of complications such as infected pancreatic necrosis, abscesses, and infected pseudocysts, herald the development of a deteriorating disease process that is associated with considerable morbidity and mortality.<br />
Cont…<br />The present meta-analysis does not support the use of prophylactic antibiotics to reduce the frequency of surgical intervention, infected necrosis, or mortality in patients with SAP. They may, however, be beneficial in protecting against the development of nonpancreatic infections.<br />The mechanisms of which are not understood.<br /> This does need to be weighed against the significant adverse events associated with antibiotics, including increased bacterial resistance and fungal infections.<br />
Cont….<br />Limitations <br /><ul><li>These limitations were inherent in the primary study design such as inclusion criteria, duration and dosing of antibiotics, assessment of severity of disease, nutritional support, and resuscitative measures.
Other notable limitations included the relatively small number of patients in each individual study, different outcome measurements, and the inclusion of low-quality studies.</li></li></ul><li>Cont….<br /><ul><li>Concerns over the increasing prevalence of multi drug resistant bacterial and fungal infections in the setting of often prolonged prophylactic antibiotic use in SAP have been raised because this is associated with poor outcome.
Such complications can not be evaluated because individual patient data were not available.</li></li></ul><li>Summary<br /><ul><li>The use of prophylactic systemic antibiotics to prevent infection and reduce mortality in severe acute pancreatitis (SAP) remains a contentious issue.
Systemic review and meta-analysis until May 2008 was used.
Systematic search of MEDLINE ,EMBASE and Cochrane central register of controlled trial used.
Manually searched the references of original/</li></ul> review articles and evaluated symposia proceedings, poster presentations, and abstracts from major gastrointestinal and surgical meetings.<br />
Cont….<br /><ul><li>Relative risk (RR) reduction, absolute risk reduction, and number needed to treat were calculated and are reported with 95% confidence intervals.
Results were subjected to sensitivity analysis to determine heterogeneity among studies.
There were 253 patients with SAP who received prophylactic antibiotics, and 249 patients were randomized to the placebo arm.</li></li></ul><li>Cont…..<br />AIM<br /><ul><li>Does prophylactic antibiotic protect against infected necrosis, surgical intervention, or reducing mortality? </li></li></ul><li>Answer <br />NO<br />The present meta-analysis presents conclusive evidence that antibiotic prophylaxis for SAP is not beneficial in protecting against infected necrosis, surgical intervention, or reducing mortality. If there is a limited benefit, it is in preventing nonpancreatic infections.<br />
Thanks for your attention<br />Dr. Mohammed Alshehri<br />