Risk factors for postoperative complications after open infrarenal abdominal aortic aneurysm repair in Koreans

Aortic ischemia-reperfusion injury and potency of fluoxetine

Objectives

Due to cross-clamping of the aorta during aortic aneurysm surgeries, ischemia-reperfusion (IR) develops, and it may cause damage to the aorta itself or even to remote organs by oxidative stress or inflammation. Fluoxetine (FLX) which might be used in the preoperative period for its tranquilizing effect also has antioxidant effects in short-term use. The purpose of our study is to examine whether FLX protects aorta tissue, against the damage caused by IR.

Materials and Methods

Three groups of Wistar rats were formed randomly. 1) Control group (sham-operated), 2) IR group (60 min ischemia+120 min perfusion), and 3) FLX+IR group (FLX dose was 20 mg/kg for 3 days IP before IR). At the end of each procedure, aorta samples were collected, and oxidant-antioxidant, anti-inflammatory, and anti-apoptotic status of the aorta were evaluated. Histological examinations of the samples were provided.

Results

Levels of LOOH, MDA, ROS, TOS, MPO, TNFα, IL-1β, IL-6, NF-kB, MMP-9, caspase-9, 8-OHdG, NO, and HA were found to be significantly increased in the IR group compared with control (P<0.05) and SOD, GSH, TAS, and IL-10 levels were significantly lower (P<0.05). FLX significantly decreased LOOH, MDA, ROS, TOS, MPO, TNFα, IL-1β, IL-6, NF-kB, MMP-9, caspase-9, 8-OHdG, NO, and HA levels in the FLX+IR group compared with IR group (P<0.05) and increased IL-10, SOD, GSH, and TAS (P<0.05). FLX administration prevented the deterioration of aortic tissue damage.

Conclusion

Our study is the first study that demonstrates FLX-mediated suppression of IR injury in the infrarenal abdominal aorta by antioxidant, anti-inflammatory, and anti-apoptotic properties.

Relationship between intraoperative dopamine infusion and postoperative acute kidney injury in patients undergoing open abdominal aorta aneurysm repair

Background

Acute kidney injury (AKI) is one of the most common complications in patients undergoing open abdominal aortic aneurysm (AAA) repair. Dopamine has been frequently used in these patients to prevent AKI. We aimed to clarify the relationship between intraoperative dopamine infusion and postoperative AKI in patients undergoing open AAA repair.

Methods

We analyzed 294 patients who underwent open AAA repair at a single tertiary center from 2009 to 2018, retrospectively. The primary outcome was the incidence of postoperative AKI, determined by the Kidney Disease Improving Global Outcomes definition, after open AAA repair. Secondary outcomes included survival outcome, hospital and intensive care unit length of stay, and postoperative renal replacement therapy (RRT).

Results

Postoperative AKI occurred in 21.8% (64 out of 294 patients) The risk of postoperative AKI by intraoperative dopamine infusion was greater after adjusting for risk factors (odds ratio [OR] 2.56; 95% confidence interval [CI], 1.09–5.89; P = 0.028) and after propensity score matching (OR 3.22; 95% CI 1.12–9.24; P = 0.030). On the contrary, intraoperative norepinephrine use was not associated with postoperative AKI (use vs. no use; 19.3 vs. 22.4%; P = 0.615). Patients who used dopamine showed higher requirement for postoperative RRT (6.8 vs. 1.2%; P = 0.045) and longer hospital length of stay (18 vs. 16 days, P = 0.024).

Conclusions

Intraoperative dopamine infusion was associated with more frequent postoperative AKI, postoperative RRT, and longer hospital length of stay in patients undergoing AAA repair, when compared to norepinephrine. Further prospective randomized clinical trial may be necessary for this topic.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12871-022-01624-6.

Protective Effect of Thymosin β4 against Abdominal Aortic Ischemia-Reperfusion-Induced Acute Lung Injury in Rats

Background and objectives: Ischemia-reperfusion (IR) caused by infrarenal abdominal aorta cross-clamping is an important factor in the development of ischemia-reperfusion injury in various distant organs. Materials and Methods: We investigated potential antioxidant/anti-inflammatory effects of thymosin beta 4 (Tβ4) in a rat model of abdominal aortic surgery-induced IR. Tβ4 (10 mg/kg, intravenous (i.v.)) was administered to rats with IR (90-min ischemia, 180-min reperfusion) at two different periods. One group received Tβ4 1 h before ischemia, and the other received 15 min before the reperfusion period. Results: Results were compared to control and non-Tβ4-treated rats with IR. Serum, bronchoalveolar lavage fluid and lung tissue levels of oxidant parameters were higher, while antioxidant levels were lower in the IR group compared to control. IR also increased inflammatory cytokine levels. Tβ4 reverted these parameters in both Tβ4-treated groups compared to the untreated IR group. Conclusions: Since there is no statistical difference between the prescribed results of both Tβ4-treated groups, our study demonstrates that Tβ4 reduced lung oxidative stress and inflammation following IR and prevented lung tissue injury regardless of timing of administration.

One-Stage Repair of Adult Aortic Coarctation and Concomitant Cardiac Diseases: Ascending to Abdominal Aorta Extra-Anatomical Bypass Combined with Cardiac Surgery

BACKGROUND

To evaluate one-stage repair with ascending to abdominal aorta extra-anatomical bypass combined with cardiac surgery for adult aortic coarctation (COA) concomitant with cardiac diseases.

METHODS

Between February 2009 and September 2016, 24 consecutive patients (79.17% male, mean age 36.04±13.67years) with COA and concomitant cardiac diseases underwent one-stage repair (ascending to abdominal aorta extra-anatomical bypass combined with cardiac surgery). Two (2) patients who underwent off-pump coronary artery surgery combined with ascending to abdominal aorta bypass did not require cardiopulmonary bypass. Twenty-two (22) patients underwent one-stage repair under cardiopulmonary bypass.

RESULTS

No in-hospital mortality was observed. There was a significant reduction in baseline systolic blood pressure from 159.80±23.58 to 127.0±6.86mmHg. Mean upper-lower limb blood gradient pressure decreased significantly from 37.80±8.73 to 11.47±2.12mmHg after surgery. Two (2) patients required prolonged mechanical ventilation for respiratory dysfunction. One patient needed temporary continuous renal replacement therapy. No re-exploration for bleeding and gastrointestinal complications was needed. There was no postoperative paraplegia or permanent neurological abnormalities. Grafts were patent for all patients and no graft-related complications were observed in the hospital. Median follow-up was 41.50 months (interquartile range [IQR] 16.75-64.50 months) and 6-year survival was 76.39%. Median number of antihypertensive drugs was 0 (IQR 0-1), which was a significant reduction compared with preoperative drugs (2, IQR 1-3).

CONCLUSIONS

Ascending to abdominal extra-anatomical aorta bypass combined with cardiac surgery is a safe and effective one-stage repair technique for patients with COA concomitant with cardiac diseases.

Abdominal aortic aneurysm repair in octogenarians is associated with higher mortality compared with nonoctogenarians

OBJECTIVE

Age is a well-known independent risk factor for death after abdominal aortic aneurysm (AAA) repair. However, there is significant debate about the utility of AAA repair in older patients. In this study, mortality outcomes after endovascular AAA repair (EVAR) and open AAA repair (OAR) in octogenarians (aged ≥80 years) were compared with younger patients (aged <80 years).

METHODS

All patients recorded in the Vascular Quality Initiative database (2002-2012) who underwent infrarenal AAA repair were included. Univariable and multivariable statistics were used to compare perioperative (30-day) and 1-year mortality outcomes between octogenarians vs nonoctogenarians for OAR and EVAR.

RESULTS

During the study period, 21,874 patients underwent AAA repair (OAR, 5765; EVAR, 16,109), including 4839 octogenarians (OAR, 765; EVAR, 4074) and 17,035 nonoctogenarians (OAR, 5000; EVAR, 12,035). Octogenarians (mean age, 83.0 ± 0.1 years) were less frequently male (66% vs 75%) and had a higher prevalence of congestive heart failure (9.9% vs 7.1%), chronic renal insufficiency (12.2% vs 7.5%), and a history of aortic surgery (14.3% vs 7.7%) compared with nonoctogenarians (P < .01 for all). Intraoperative use of blood transfusions and vasopressors was more common in octogenarians for OAR (blood: 3.3 ± 4.4 vs 1.8 ± 3.7 units; vasopressors: 45.2% vs 32.8%) and EVAR (blood: 0.43 ± 1.7 vs 0.31 ± 1.6 units; vasopressors: 7.6% vs 5.7%; P < .01 for all). Contrast dye volumes used during EVAR were similar in octogenarians and nonoctogenarians (108 ± 71 vs 107 ± 68 mL; P = .18). Perioperative mortality after OAR was 20.1% in octogenarians compared with 7.1% in nonoctogenarians (P < .01). Perioperative mortality after EVAR was 3.8% in the octogenarians compared with 1.6% in nonoctogenarians (P < .01). One-year mortality among octogenarians vs nonoctogenarians was 26% vs 9.7% for OAR and 8.9% vs 4.3% for EVAR (log-rank test, P < .01 for both). Multivariable analysis controlling for baseline and intraoperative differences between groups demonstrated that age ≥80 years increased the risk of 30-day and 1-year mortality after AAA repair by 223% and 187%, respectively (P < .01 for both).

CONCLUSIONS

AAA repair should be approached with extreme caution in octogenarians. Perioperative and 1-year mortality rates after OAR are particularly high in the older population, suggesting that the appropriate aneurysm size threshold for OAR might be larger due to the greater operative risk in octogenarian patients.

Significance of serum potassium level monitoring during the course of post-operative rehabilitation in patients with hypokalemia

OBJECTIVE

Our objective was to evaluate the significance of pre-hospital and post-operative serum potassium level monitoring and hypokalemia intervention in laparotomy patients with hypokalemia.

METHOD

A total of 118 laparotomy patients with hypokalemia were randomly divided into an intervention group (N = 60) and a control group (N = 58). Blood samples were collected for measurement of potassium levels at various time points (pre-admission, admission, 24 h and 48 h post-operation) for both groups. Hypokalemia interventions were administered to patients in the intervention group in the pre-admission period and the post-operative period. Visceral dynamics were assessed after laparotomy in both groups.

RESULT

Average serum potassium levels at admission, time period of drinking, and time of first bowel sound after laparotomy differed significantly (p < 0.001) between the two groups. Average serum potassium levels, first time of defecation, urination, and ambulation at 24 h and 48 h post-operation differed significantly (p < 0.05) between the two groups.

CONCLUSION

An optimal pathway of serum potassium monitoring not only saves limited ward space but also allows for early correction of hypokalemia in patients undergoing laparotomy.

Pharmacokinetics and pharmacodynamics of propofol in patients undergoing abdominal aortic surgery

Available propofol pharmacokinetic protocols for target-controlled infusion (TCI) were obtained from healthy individuals. However, the disposition as well as the response to a given drug may be altered in clinical conditions. The aim of the study was to examine population pharmacokinetics (PK) and pharmacodynamics (PD) of propofol during total intravenous anesthesia (propofol/fentanyl) monitored by bispectral index (BIS) in patients scheduled for abdominal aortic surgery. Population nonlinear mixed-effect modeling was done with Nonmem. Data were obtained from ten male patients. The TCI system (Diprifusor) was used to administer propofol. The BIS index served to monitor the depth of anesthesia. The propofol dosing was adjusted to keep BIS level between 40 and 60. A two-compartment model was used to describe propofol PK. The typical values of the central and peripheral volume of distribution, and the metabolic and inter-compartmental clearance were V(C) = 24.7 l, V(T) = 112 l, Cl = 2.64 l/min and Q = 0.989 l/min. Delay of the anesthetic effect, with respect to plasma concentrations, was described by the effect compartment with the rate constant for the distribution to the effector compartment equal to 0.240 min(-1). The BIS index was linked to the effect site concentrations through a sigmoidal E(max) model with EC(50) = 2.19 mg/l. The body weight, age, blood pressure and gender were not identified as statistically significant covariates for all PK/PD parameters. The population PK/PD model was successfully developed to describe the time course and variability of propofol concentration and BIS index in patients undergoing surgery.