TAPB and RSB protects cardiac diastolic function in elderly patients undergoing abdominopelvic surgery: a retrospective cohort study

Subjects

This was a non-randomized, retrospective clinical observational study, based on previous perioperative management date (between June 2015 and December 2017), and was approved by our hospital clinic research committee. The need for consent was waived for this study, as data was previously collected as part of regular hospital procedures and all patients previously consented to data collection prior to surgery. Patients were contacted in May 2018 before enrolling in the current retrospective study to consent to the use of their data for the purpose of this research. It included 38 patients who were scheduled for grade 3–4 through open abdominal and pelvic surgery (Table 1) with American Society of Anesthesiologists physical status II–III, age >60 years (70.21 ± 6.94), and demonstrated a sinus rhythm, mitral valvular (MV) e velocity <10 cm/s, and averaged LV E/e >9 cm/s by TEE evaluation after anesthesia induction hemodynamics stability indicating diastolic dysfunction (Ammar et al., 2016; Matyal et al., 2011). The hemodynamics stability was that hemodynamic values were maintained between 15% pre-induction baseline values.

Patients who met these criteria during surgeries from June 2015 to December 2017 were enrolled, following approval by our hospital ethics committee (2018KY173) and registered at Chinese Clinical Trial Registry (ChiCTR1900021671). Patients with the following characteristics were excluded: left ventricular ejection fraction (LVEF) <60% preoperative by trans-thoracic echocardiography, preexisting valvular disease, pericardia disease, and serious LV hypertrophy, infection on the puncture site, history of allergy to local anesthetics, preexisting neurological disorders, and/or coagulation system disorders (recent bleeding from esophageal varicose veins or hypocoagulability with prothrombin time <20%).

Anesthesia conditions

Because of complicated operations, patients underwent routine monitoring, including 5-lead electrocardiography and pulse oximetry. A central venous line and femoral arterial line were installed after anesthesia induction. Anesthesia was induced by propofol 1.5 mg/kg (Fresenius Kabi AB, Uppsala, Sweden), fentanyl 4 µg/kg (Renfu Pharmaceutical Co. Ltd., Yichang, China), and rocuronium 1 mg/kg (N.V. Organon, Oss, Netherland); it was maintained by either sevoflurane combining with fentanyl 2 µg/kg/h after skin incision (S group) or sevoflurane combining with TAPB and RSB (ST group). During the surgery, the concentration of sevoflurane, with 1 L/min 80% oxygen and air, was maintained stable MAC level by adjusting to maintain bispectral index (BIS) range between 40 and 50, and hemodynamic stability in both groups. Rocuronium was added as need 0.2 mg/Kg. Cardiac preload monitored by central venous pressure (CVP) was kept within the normal range (5–12 cm H₂O) by intravenous fluid infusion.

Bilateral transversus abdominis plane block and rectus sheath block was implemented by visible ultrasound guiding after anesthesia induction and inserting the trans-esophageal ultrasound probe as the description (Xia et al., 2020). The local anesthetic of transversus abdominis plane block was injected between the fascial planes of the internal oblique and transversus abdominis muscles causing the anesthetic diffusion between the internal oblique and transversus abdominis. For the rectus sheath block, local anesthetic was injected into anterior to the posterior rectus sheath causing distribution between the muscle and posterior plane. The combination local anesthetic of 1% Lidocaine (ZhaoHui Pharmaceutical Co. Ltd., shanghai, China) and 0.375% ropivacaine (AstraZeneca AB, Sweden) 10 ml was implemented at each injection sites of four locations.

Heart rate (HR) and mean arterial pressure (MAP) were kept stability at an appropriate level by treating with atropine (HR was below 50 bpm), β1-adrenergic receptor antagonist esmolol (HR was above 100 bpm), α1-adrenergic receptor agonist phenylephrine (MAP was below 60 mmHg) and calcium channel blocker perdipine (MAP was above 120 mmHg). The values were obtained after anesthesia induction (HR₁, MAP₁), thus representing baseline, and 1 h after that (HR₂, MAP₂), thus illustrating hemodynamic variation at 1 h after induction hemodynamics stability to exclude the effect of after-load.

Diastolic function

TEE was performed according to the practice guidelines of perioperative TEE established by the American Society of Anesthesiologists and European Association of Cardiovascular, and was executed by the same experienced anesthesiologist as the above procedures. After anesthesia induction and endotracheal intubation, an ultrasonic probe was inserted in the mid-esophageal with four-chamber view to ensure that the ultrasound beam was parallel to the long-axis movement of the mitral annular and that the sample volume was placed between the tips of the mitral valve leaflets. And relevant diastolic function parameters were collected after anesthesia induction hemodynamics stability and 1 h later respectively.

With a pulsed-wave technique, some Doppler parameters were obtained, including the transmitral peak flow velocity of early diastolic filling (E) and the transmitral peak flow velocity of late diastolic filling (A) (Shanewise et al., 1999; Nagueh et al., 2009). In addition to blood stream velocity, mitral annular tissue velocity can be recorded by spectral Tissue Doppler Imaging (TDI). By this method, the sample volume was assessed at the level of mitral lateral annular from the 4-chamber view, and parameters were measured based on mitral lateral annular movement in early diastole (e) and in late diastole (a). Concurrently, the E/A, e/a, and E/e ratios were obtained.

Statistical methods

Although Our research was retrospective, we evaluated the reasonableness of the sample size based on the the results of the main indicator e/a (SD_sev = 0.3; Mean_sev =0.85; Mean_sev+TAPB = 1.19). With a power of 0.8 and a significance level of 0.05, at least 17 patients were need in each group. Assuming a dropout rate of 10%, 19 patients were selected for each group. Date were collected in Microsoft excel and assessed by using SPSS version 22.0 (IBM Corporation, Armonk, NY, USA). As shown in Fig. 1, we divided patients into two groups, sevoflurane group (S group) and sevoflurane combining with TAPB and RSB group (ST group), according to their strategies for maintaining anesthesia. Continuous variables were presented as Mean ± SD (standard deviation) and compared by using a linear mixed model between the 2 groups and using a paired t-test in group. For all assessments, a probability value of p < 0.05 (2-sided) was considered statistically significant.

Baseline characteristics

The baseline characteristics of our patients were presented in Table 1. The mean age of the 38 consecutive study patients (19 men and 19 women) was 70.21 ± 6.94 years. Based on American Society of Anesthesiologists (ASA) classification, 37 patients were class II and 1 patient was class III. The mean duration time of surgery was 3.20 ±1.08 h. Patients exhibited the following complications: hypertension (9) and Diabetes Mellitus (3) and medications were continued until the morning of surgery. Of the 38 patients, 19 were administered sevoflurane and 19 were administered sevoflurane combining with TAPB and RSB during anesthesia maintenance.

The anesthesia maintenance management informations were shown in Table 2. ST group decreased the use of sevoflurane indicated with maintaining minimum alveolar concentration (MAC) (1.22 ± 0.13 vs. 0.77 ± 0.67), however, there were no statistical significance. And there were no significantly difference in infusion volume, blood loss, urine output, and vasoactive agents between S group and ST group from anesthesia induction to 1 h later.

Hemodynamic features after anesthesia induction hemodynamics stability (T₁) and 1 h later (T₂)

There were no statistical differences in HR₁ (68.37 ± 11.55 vs. 68.05 ± 11.20) and MAP₁(90.32 ± 15.47 vs. 91.68 ± 11.79); HR₂ (68.79 ± 10.14 vs. 67.47 ± 9.63) and MAP₂ (91.84 ± 12.13 vs. 88.21 ± 11.02); CVP₁ (8.26 ± 1.24 vs. 8.26 ± 1.41) and CVP₂ (8.47 ± 1.58 vs. 8.53 ± 1.57) between S group and ST groups. Results were shown in Table 3.

Transmitral diastolic Doppler flow characteristics after anesthesia induction hemodynamics stability (T₁) and 1 h later (T₂)

The TEE probe was securely placed in all patients without esophageal bleeding. We analyzed the parameters, shown in Table 4, regarding diastolic function investigated by transmitral diastolic doppler flow, comparing S group with ST group after anesthesia induction hemodynamics stability (T₁) and 1 h later (T₂). ST group caused some improvement of LV diastolic function 1 h after T1, as the evidence by significant decreases in E/A in S group but increases in ST group (1.07 ± 0.38 vs. 1.36 ± 0.33, p = 0.022 <0.05). TEE images were shown in supplementary materials 1 and 3.

Tissue Doppler imaging characteristics after anesthesia induction hemodynamics stability (T₁) and 1 h later (T₂)

Several measurements (e, a, e/a, E/e) were implemented simultaneously to investigate diastolic function by tissue Doppler shown in Table 5. However, unlike transmitral diastolic Doppler flow characteristics, both S group and ST group caused some improvement of left ventricular diastolic function according to the TDI characteristics. Improvement of LV diastolic function was greater in ST group than in S group 1 h after anesthesia induction stability, evidenced by more significant increase e/a (0.85 ± 0.30 vs. 1.19 ± 0.43, P = 0.005 <0.05) and significant decreases in a value in ST group (7.12 ± 1.67 vs. 5.45 ± 1.48, p = 0.009 <0.05). At the same time, some parameters, both S group and ST groups increasing in e value (5.71 ± 1.31 vs. 6.25 ± 2.25) and decreasing in E/e (14.25 ± 6.42 vs. 13.85 ± 5.85) 1 h after anesthesia induction stability, indicated diastolic function improvement, however, there were no statistical significance. TEE images were shown in supplementary materials 2 and 4.