Cardiovascular Journal of Africa: Vol 32 No 5 (SEPTEMBER/OCTOBER 2021)

CARDIOVASCULAR JOURNAL OF AFRICA • Volume 32, No 5, September/October 2021 258 AFRICA (MedCalc Software BVBA, Ostend, Belgium) and ordinary one-way ANOVA was performed using GraphPad Prism version 7.0c (GraphPad Software, La Jolla California USA). Results For the artery, the NEC values of the clamp and tourniquet groups were lower than those of the control group ( p ≤ 0.001, p = 0.007, respectively), while the other parameters of the clamp and tourniquet groups were higher than those of the control group (SEI, p ≤ 0.001 and p ≤ 0.001; SLEI, p ≤ 0.001 and p = 0.004; TMSMV, p = 0.004 and p = 0.008; total score, p ≤ 0.001 and p ≤ 0.001, respectively). When the clamp and tourniquet groups were compared, no differences were found for all vascular parameters (Fig. 1C, D, Table 2). For the vein, the NEC values of the clamp and tourniquet groups were lower than those of the control group (both p ≤ 0.001). The SEI values were higher in the clamp group than in the control group ( p = 0.055). In the tourniquet group, all values were higher than in the control group ( p = 0.023) (SLEI, both p ≤ 0.001). There was no difference between the distribution of plaque in the distal, middle and proximal regions of vessels in the clamp and tourniquet groups (Fisher’s exact test, p > 0.05) ( p = 0.286, 0.265, 1.00, respectively). No difference was found between the clamp and tourniquet groups for all parameters. For nerve and muscle tissue, there were no differences between the groups regarding femoral nerve injury scores, rectus femoris and tibialis anterior degeneration, inflammation and total injury scores ( p = 0.533, 0.876, 0.604, 0.756, respectively). There were also no differences between the middle regions of vessels of the clamp group and the mean values of the tourniquet group (Mann–Whitney U -test, p > 0.05). Protein levels were evaluated by Western blotting. The samples were normalised using beta-actin levels. The bands were analysed by densitometry and normalised using Image J Software (National Institutes of Health, USA). Statistical analysis was carried out by ordinary one-way ANOVA using GraphPad Prism version 7.0c (GraphPad Software, La Jolla California USA) and no statistically significant differences were found between the groups for TNF- α values ( p = 0.1712) (Fig. 3). Discussion To our knowledge, this is the first study comparing tourniquet and arterial clamping in the literature. We found no significant difference between tourniquet and clamp methods regarding histological and inflammatory response in the vessel. Therefore, the clamp method can be used in orthopedic oncological, trauma and revision hip-joint surgeries that are unsuited to a tourniquet. The external iliac artery or axillary artery can be Table 2. Clamp versus tourniquet versus control group according to injury parameters Group NEC SEI SLEI TMSMV Total score Clamp Min–max 1–27 1–3 0–1 0–2 1–5 Mean ± SD (median) 14.43 ± 10.6 (18) 1.71 ± 0.95 (1) 0.29 ± 0.49 (0) 1.14 ± 0.69 (1) 3.14 ± 1.46 (3) Tourniquet Min–max 9–30 1–2 0–1 0–2 1–4 Mean ± SD (median) 18 ± 7.55 (15) 1.57 ± 0.53 (2) 0.43 ± 0.53 (0) 0.43 ± 0.79 (0) 2.43 ± 1.4 (3) Control Min–max 20–33 0–0 0–0 0–2 0–2 Mean ± SD (median) 24.57 ± 4.2 (25) 0 ± 0 (0) 0 ± 0 (0) 0.43 ± 0.79 (0) 0.43 ± 0.79 (0) p -value 0.099 0.001* 0.174 0.103 0.004* * Kruskal–Wallis test, p < 0.05. NEC: number of endothelial cells; SEI: score of endothelial injury; SLEI: score of lamina elastica interna injury; TMSMV: tunica media smooth muscle vacuolation. Clamp group 1 2 3 TNF- α (17 kDa) Beta actin (42 kDa) Tourniquet group TNF- α (17 kDa) Beta actin (42 kDa) Control group TNF- α (17 kDa) Beta actin (42 kDa) TNF- α protein expression levels Clamp Tourniquet Control Adjusted density 2.0 1.5 1.0 0.5 0.0 Fig. 3. (A) Representative immunoblotting images of TNF- α protein expression were examined by Western blotting. Beta actin was used as equal loading control in analysis. (B) Densitometric analysis of Western blot results. A B