## 4 Discussion  
This study was conducted on an extremely heterogeneous population, including every patient who underwent cardiac surgery; we tried to confront two different groups with different analgesic strategies in terms of pain management, recovery capacity and postoperative outcome. Due to the increased life expectancy, heart surgery has become frequent in the elderly population; in our study, while the mean age of our patients was 70 years old, we faced many patients aged 80 years or more and were affected by many comorbidities. To best manage this frail population, it is mandatory to devise an anaesthetic plan aimed at minimizing the impact on the patient's vital functions and homeostasis [17]. Periop-erative strategies must be adopted to reduce surgical invasiveness, post-operative pain, \begin{table}
\begin{tabular}{c c c c} \hline \hline  & **Parastermal** & **Control** & \(p\)**-Value** \\ \hline
**Intraoperative fentanyl (\(\gamma\))** & 406.3 \(\pm\) 81.6 & 864.3 \(\pm\) 154.4 & **<0.001** \\
**Intraoperative reimfientanil (\(\gamma\))** & 336.1 \(\pm\) 13.1 & 338.3 \(\pm\) 13.5 & 0.3367 \\
**Postoperative pain** & & & \\ (NRS max 0-10) & & & \\ Extubation & 2 (0–4.5) & 3 (0–6) & 0.07 \\
0–6 h & 0 (0–3) & 2 (0–4) & 0.46 \\
6–12 h & 0 (0–2) & 0 (0–2) & 0.57 \\
12–24 h & 1 (0–2) & 2 (0–3) & 0.69 \\
**Postoperative opacities consumption** & & & \\ Yes & 19 (30\%) & 18 (29\%) & 0.8 \\ No & 44 (70\%) & 45 (71\%) & \\
**Time to first opioid (min)** & 30 (10–45) & 30 (11-60) & 0.6 \\
**Morphine consumption 0-24 h (mg)** & 0 (0–2) & 0 (0–2) & \textgreater{}0.9 \\ \hline \hline \end{tabular} Values are expressed in mean \(\pm\) standard deviation; median (interquartile range); number of patients (\%); NRS (numeric rating scale).  
\end{table} 
Table 2: Main Outcomes. \begin{table}
\begin{tabular}{c c c c} \hline \hline  & **Parastermal** & **Control** & \(p\)**-Value** \\ \hline
**Time to extubation (min)** & \(191\pm 48\) & \(305\pm 62\) & **<0.001** \\
**Pulmonary performance (balls moved up)** & & & \\ Basal & 3 (2–3) & 3 (2–3) & 0.9 \\ After extubation & 2 (1–2) & 1 (1–2) & **0.045** \\
**Side effects** & & & \\ Nausea & 2 (3\%) & 1 (2\%) & – \\ Vomni & 1 (2\%) & 2 (3\%) & – \\ Delurium & 1 (2\%) & 2 (3\%) & – \\ \hline \hline \end{tabular} Values are expressed in mean \(\pm\) standard deviation; median (interquartile range); number of patients (\%).  
\end{table} 
Table 3: Secondary Outcomes. anaesthetic drugs usage and promote early respiratory recovery and patient-autonomous mobilization [1]. Pain, in fact, plays a central role in this therapeutic process; it reduces thoracic excursion and influences respiratory functional recovery, finally promoting pulmonary complications, such as pneumonia, pleural effusion and lung atelectasis. Different regional anaesthetic protocols have been proposed to better control sternal pain after cardiac surgery. Starting from neuraxial techniques, different approaches have been developed to target the thoracic fascial plane where intercostal nerves from T1 to T11 lay, such as the pectoral blocks [18; 19], the serratus anterior plane block [20], the transversus thoracic muscle block [21], the erector spinae block [22] and the parasternal block. All these blocks contribute to obtaining a better control of thoracic pain in heart surgery, reducing recovery time and improving dismission time [23]. The parasternal block is one of the more promising fascial blocks to manage sternal pain as described in the recent studies conducted by [PERSON] et al. [24; 25]. In our study, post-operative pain, expressed with an NRS scale from 0 to 10, was very low in both groups in absence of a significant statistical difference (Figure 2). These results are similar to the study by [PERSON] et al. [11], as they found a marginal decrease in postoperative pain levels, although they use a longer acting local anaesthetic (liposomal bupivacaine).