Anesthetic management of abdominal aortic surgery: a retrospective review of perioperative complications

Prediction of hemodynamic fluctuations after induction of general anesthesia using propofol in non-cardiac surgery: a retrospective cohort study

Background

Although propofol is a common anesthetic agent for the induction of general anesthesia, hemodynamic fluctuations are occasionally prominent during induction/intubation. The aims of this study were to determine the influential factors on enhanced hemodynamic fluctuation and to establish a prediction formula to quickly determine the dose of propofol to protect against hemodynamic fluctuations.

Methods

This retrospective cohort study patients (n = 2097) were 18 years or older. They underwent general anesthesia induction using propofol and orotracheal intubation for non-cardiac surgery at Kyushu University Hospital during April 2015 to March 2016. Preoperative patient clinical information was collected from anesthesia preoperative evaluation records. Intraoperative data were obtained from computerized anesthesia records. If patients’ post-induction mean arterial blood pressure (MAP) decreased or increased 30% or more from their pre-induction MAP, they were determined to have enhanced hemodynamic fluctuations. Unconditional logistic regression was used to assess the adjusted odds ratios (ORs) and 95% confidence intervals (CIs). Structural equation modeling (SEM) was conducted to simultaneously examine the direct and indirect effect (path coefficient = r) of potential variables.

Results

In the SEM analysis, age was significantly associated with enhanced hemodynamic fluctuations (adjusted odds ratio = 1.008, 95% CI = 1.001–1.015, P = 0.03). Age (path coefficient (r) = − 0.0113, 95% CI = − 0.0126–0.010, P < 0.001), American Society of Anesthesiologists physical status (ASA-PS) (r = − 0.0788, 95% CI = − 0.1431–0.0145, P = 0.02), sex (r = 0.057, 95% CI = 0.0149–0.9906, P = 0.01), and fentanyl dose (r = 0.1087, 95% CI = 0.0707–0.1467, P < 0.001) influenced the dose of propofol in induction. The prediction formula of “Propofol dose (mg) = [2.374 – 0.0113 × age (year) – 0.0788 (if ASA-PS 3 or 4) + 0.057 (if female) + 0.1087 × fentanyl dose (μg/kg)] × body weight (kg)” was derived.

Conclusions

Age was associated with hemodynamic fluctuations in induction. Although the prediction formula is considered to be acceptable, future studies validating whether it can decrease patients’ risk of enhanced hemodynamic fluctuations in clinical situations are necessary.

Ischemic liver dysfunction after elective repair of infrarenal aortic aneurysm: incidence and outcome

OBJECTIVE

To assess the frequency of early postoperative liver dysfunction in patients undergoing elective infrarenal aortic aneurysm repair, their hospital course, and outcome.

DESIGN

A retrospective case-control study.

SETTING

A single tertiary referral center.

PARTICIPANTS

A review of medical records of 942 consecutive asymptomatic patients with normal preoperative liver function test results who had elective infrarenal aortic aneurysm repair with infrarenal aortic cross-clamping. The authors selected all patients who had an acute increase in serum hepatic enzyme levels (minimum fivefold increase in aspartate aminotransferase [AST] and twofold increase in lactate dehydrogenase [LDH] levels) within the first 7 perioperative days (study patients). The control group consisted of 42 patients with normal postoperative liver function test results, matched by age, sex, and year of surgery to study patients.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Aortic cross-clamping times, lowest intraoperative blood pressure, duration of hypotension (systolic blood pressure < or = 95 mmHg), lowest intraoperative base deficit, and estimated blood loss were compared between control and study patients. The study also analyzed perioperative metabolic, hemostatic, hepatic, and renal function variables; the intraoperative course; postoperative complications; and inhospital outcome. Fourteen of 942 patients (1.5%) comprised a study group. In 11 patients (1.2%), AST and LDH levels moderately increased, and three patients (0.3%) developed changes consistent with a diagnosis of acute ischemic hepatitis (AIH). In all patients, the serum liver enzyme levels peaked between 24 and 72 postoperative hours. Three patients with AIH developed concomitant acute renal failure; one had associated disseminated intravascular coagulation (DIC) and died. Of 11 patients with moderate increases, one subsequently developed multisystem organ failure and died. The overall in-hospital mortality rate for patients with postoperative liver dysfunction was 14% (2/14) and for the control group it was 2.3% (1/42). The duration of hypotension and metabolic acidosis were more pronounced in patients who postoperatively developed liver dysfunction (both p < 0.001); however, study and control patients did not differ in the duration of aortic cross-clamping, lowest intraoperative blood pressure, or estimated blood loss.

CONCLUSION

Liver enzyme levels acutely increased in 1.5% of patients after elective infrarenal aortic aneurysm repair with infrarenal cross-clamping. In patients with moderately elevated serum liver enzyme levels, postoperative recovery was relatively uncomplicated, whereas all three patients with AIH developed acute renal failure and had a more complicated postoperative course. Those with postoperative liver dysfunction had a longer duration of intraoperative hypotension and more pronounced metabolic acidosis.

Supraceliac, but not infrarenal, aortic cross-clamping upregulates neutrophil integrin CD11b

OBJECTIVE

To evaluate the effects of supraceliac and infrarenal aortic cross-clamping on the expression of neutrophil integrin in CD11b (a marker of systemic cytokine release).

DESIGN

Two groups, determined by anatomic placement of aortic cross-clamp. Laboratory personnel were blinded as to group assignment.

SETTING

University teaching and community hospitals. Laboratory facilities used were university and Veteran's Affairs medical centers.

PARTICIPANTS

Patients scheduled for aortic surgery.

INTERVENTIONS

Blood sampling was performed at baseline, after 30 minutes of aortic cross-clamp duration, 30 and 90 minutes after reperfusion (for tumor necrosis factor-alpha plasma levels in infrarenal cross-clamp group), and at baseline and 90 minutes reperfusion (for neutrophil CD11b expression quantification) in both groups.

MEASUREMENTS AND MAIN RESULTS

Tumor necrosis factor-alpha measured by ELISA technique did not change at any time period in the infrarenal clamping group. Neutrophil CD11b expression, measured by double antibody staining and FACScan analysis, did not change significantly at 90 minutes of reperfusion in the infrarenal group, but increased significantly (p < 0.05) in the supraceliac aortic cross-clamp group.

CONCLUSION

Neutrophil integrin CD11b has been demonstrated to be the primary adhesive glycoprotein responsible for neutrophil organ entrapment and subsequent neutrophil-mediated reperfusion injury. These results suggest that upregulation of neutrophil integrin CD11b after supraceliac aortic clamping may in part be responsible for the higher incidence of acute lung injury after thoracic aortic aneurysm repair requiring supraceliac clamping when compared with infrarenal aneurysm surgery.

Preoperative coagulopathy in ruptured abdominal aortic aneurysm predicts poor outcome

In a prospective study of 50 consecutive patients undergoing operation for ruptured abdominal aortic aneurysm, a coagulation screen was performed on admission to hospital. Twenty patients with either a platelet count < 100 x 10(9)/l or a prothrombin time > 1.5 times the control value had a mortality rate of 65 per cent (95 per cent confidence interval 45-85 per cent); a further 23 patients with normal screen results had a mortality rate of 9 per cent (95 per cent confidence interval 0-20 per cent) (P < 0.001). Seven patients, of whom three died, did not have an admission coagulation screen performed. Patient age in the study group did not have independent statistical predictive power. This study indicates that coagulopathy at the time of admission predicts poor outcome in patients with ruptured aortic aneurysm. Current management strategies are inadequate for the treatment of these patients, who can be rapidly identified on admission by means of platelet and prothrombin counts.