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Abstract

We appreciate the letter submitted to the Editor by Bosanquet and colleagues, in which they raised some interesting points about our article on the Enhanced Recovery Program (ERP) in patients who underwent abdominal aortic aneurysm repair using the retroperitoneal (RP) approach. First, they remarked that the control group had significantly greater intraoperative blood loss and transfusion requirements compared with the ERP group, suggesting that these variables should have been included in the Cox regression analysis to investigate their potential confounding effect in the fully adjusted model. Following their advice, we performed a new Cox regression analysis adjusted for potential confounders, including both intraoperative blood loss and transfusion, to evaluate the association between baseline characteristics, intraoperative variables, and type of perioperative protocol and length of hospital stay (Table). The median blood loss among all patients was 50 mL (interquartile range 25-75, 50.00-737.50 mL), and on the basis of this evaluation, we elected an intraoperative blood loss ≤50 mL as the reference value for the analysis. Neither >50 mL intraoperative blood loss (hazard ratio, 0.75 [95% confidence interval, 0.48-1.18]; P = .213) nor intraoperative blood transfusion (hazard ratio, 1.00 [95% confidence interval, 0.63-1.60]; P = .981) was associated with prolonged length of hospital stay. Thus, after the introduction of these new potential confounders in the fully adjusted Cox regression analysis, being ≥65 years and on a traditional perioperative protocol remained the only factors independently associated with prolonged hospital stay. This finding supports the important role of the ERP in functional recovery after RP abdominal aortic aneurysm repair.TableAssociation between baseline characteristics, intraoperative outcomes, and type of perioperative protocol and length of hospital stay according to Cox regression analysis fully adjusted for potential confoundersVariableProlonged hospital length of stayFull adjusted modelHR (95% CI)PGender (ref: female) Male1.15 (0.70-1.89).577Age (ref: <65 years) 65-740.69 (0.48-0.98).039 ≥750.50 (0.34-0.74).001BMI (ref: <25 kg/m2) 25-29.91.08 (0.77-1.50).669 ≥300.92 (0.62-1.37).676Diabetes (ref: absence) Presence0.99 (0.64-1.52).948Hypertension (ref: absence) Presence0.90 (0.63-1.28).548Ischemic heart disease (ref: absence) Presence1.09 (0.80-1.48).577COPD (ref: absence) Presence0.91 (0.59-1.40).652Perioperative protocol (ref: ERP) Traditional0.73 (0.54-0.97).034Intraoperative blood loss (ref: ≤50 mL) >50 mL0.75 (0.48-1.18).213Intraoperative blood transfusion (ref: absence) Presence1.00 (0.63-1.60).981BMI, Body mass index; CI, confidence interval; COPD, chronic obstructive pulmonary disease; ERP, Enhanced Recovery Program; HR, hazard ratio. Open table in a new tab BMI, Body mass index; CI, confidence interval; COPD, chronic obstructive pulmonary disease; ERP, Enhanced Recovery Program; HR, hazard ratio. Second, they referred to the left kidney “down” technique as having potential for bleeding, developing a plane anterior to the kidney, whereas they prefer a left kidney “up” approach, except in case of retroaortic left renal vein. However, in the RP approach for both aneurysmatic and Leriche diseases, we did not experience bleeding during the dissection to maintain the left kidney down. Instead, although it is more time-consuming, we do prefer such a technique because it is less traumatic as the kidney is not displaced and it seems easier to get further distal on the right renal artery. Third, they mentioned that many surgeons performing RP surgery see the clear physiologic benefits it offers over the transperitoneal (TP) route and speculate that the advantages of the RP one may have little to do with ERPs but may be primarily due to the approach itself. We agree that RP surgery offers such benefits over the TP approach; however, all patients included in our study were operated on through the RP approach, and control group patients showed slower functional recovery and longer hospital stay as opposed to patients who were on an ERP. Finally, although one of the general strategies of enhanced recovery methodology is to reduce the surgical trauma, we do agree that ERP is most likely to demonstrate greatest benefit for vascular operations involving the peritoneal cavity. As the magnitude of the surgical stress response increases with the invasiveness of the surgical operation, it seems sensible to implement strategies to attenuate such a response (ie, ERPs), in particular when the trauma of the operation cannot be reduced (eg, open TP surgery). Regarding “The effect of an Enhanced Recovery Program in elective retroperitoneal abdominal aortic aneurysm repair”Journal of Vascular SurgeryVol. 64Issue 4PreviewWe read with interest the study by Feo et al.1 As major supporters of the retroperitoneal (RP) approach for aortic surgery, we are aware of the potential benefits it provides over transperitoneal (TP) surgery.2-4 Published studies on the RP approach are of variable quality and often small case series, and there is no definitive advantage of the RP over the TP approach when physiologic parameters are assessed. There seems to be more evidence supporting the RP approach for juxtarenal, suprarenal, and redo aortic aneurysms. Full-Text PDF Open Archive