The majority of evidence favors an ability of epidural analgesia to reduce postoperative cardiovascular and pulmonary complications only after major vascular surgery or in high-risk patients .
This finding may become irrelevant because of rapid conversion of major surgery to minimally invasive techniques ( e.g. , endoluminal abdominal aortic repair ) that carry less risk of complications .
There is also consistent evidence that epidural analgesia with local anesthetics is associated with faster resolution of postoperative ileus after major abdominal surgery .
Again , this finding may also become irrelevant with the adoption of laparoscopic techniques and multimodal fast-track programs for abdominal surgery .
There is no current evidence that perineural analgesia , continuous wound catheters using local anesthetics , IV patient-controlled analgesia with opioids , or addition of multimodal systemic analgesics have any clinical ly significant beneficial effect on postoperative complications .
CONCLUSIONS : Overall , there is insufficient evidence to confirm or deny the ability of postoperative analgesic techniques to affect major postoperative mortality or morbidity .
This is primarily due to typically insufficient subject numbers to detect differences in currently low incidences of postoperative complications
BACKGROUND : Few individual clinical trials have had sufficient subject numbers to definitively determine the effects of postoperative analgesia on major outcomes .
Epidural analgesia with local anesthetics has the greatest theoretical potential to affect major outcomes and has been the most thoroughly investigated technique .
Underpowering in randomized trials reporting a sample size calculation.
OBJECTIVE The objective of this study was to determine whether st and ard deviations ( SDs ) used in sample size calculations are smaller than those found in the result ing study sample , thereby leading to underpowered studies . METHOD The predicted SD used in the sample size calculation and the actual SD of the study sample were recorded for r and omized trials recently published in one of four major journals . RESULTS Sample SD was greater than predicted SD for 80 % of endpoints . About one quarter of trials required five times as many patients as specified in the sample size calculation . CONCLUSION Trials reporting sample size calculations for continuous endpoints published in the most reputable medical journals are often underpowered . There seems to be insufficient underst and ing that the SD of a sample of patients is a r and om variable , associated with imprecision , that can not easily be extrapolated from one population to another
The majority of evidence favors an ability of epidural analgesia to reduce postoperative cardiovascular and pulmonary complications only after major vascular surgery or in high-risk patients .
This finding may become irrelevant because of rapid conversion of major surgery to minimally invasive techniques ( e.g. , endoluminal abdominal aortic repair ) that carry less risk of complications .
There is also consistent evidence that epidural analgesia with local anesthetics is associated with faster resolution of postoperative ileus after major abdominal surgery .
Again , this finding may also become irrelevant with the adoption of laparoscopic techniques and multimodal fast-track programs for abdominal surgery .
There is no current evidence that perineural analgesia , continuous wound catheters using local anesthetics , IV patient-controlled analgesia with opioids , or addition of multimodal systemic analgesics have any clinical ly significant beneficial effect on postoperative complications .
CONCLUSIONS : Overall , there is insufficient evidence to confirm or deny the ability of postoperative analgesic techniques to affect major postoperative mortality or morbidity .
This is primarily due to typically insufficient subject numbers to detect differences in currently low incidences of postoperative complications
BACKGROUND : Few individual clinical trials have had sufficient subject numbers to definitively determine the effects of postoperative analgesia on major outcomes .
Epidural analgesia with local anesthetics has the greatest theoretical potential to affect major outcomes and has been the most thoroughly investigated technique .