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Opioids are widely used in treatment of acute and chronic pain patients, and today a lot of efforts are put into individualize these therapies. Physicians would like to reduce deaths, minimize side effects and prevent toxicity, but – nevertheless PCA could represent a solution – up to date it is not yet completely reliable. A sustaining pharmacokinetic approach gives significant contribution, in particular in treatment of special populations (e.g. infants, elderly, and patients with renal/liver failure), which have a unique opioids pharmacokinetic profile to be taken into account, in order to maximize analgesic efficacy and reduce the risk of adverse events.

Pain, be it acute, chronic, or any permutation thereof, is a universal problem affecting greater than 1.5 billion people worldwide, with over 116 million in the US, and over 164 million people in Europe and Israel combined. The economic cost to society is staggering, estimated around $560–635 billion annually in the US alone for direct medical treatment costs and lost productivity. Additional complications may include over-prescribing of opiates and other potentially habit-forming substances with life-threatening side effects, as well as drug diversion and the social problems associated with substance abuse and addiction, such as illegal “pill mills,” which contributed to the approximate 600% increase in opioid prescribing in the United States from 1997 to 2007, and a 300% increase in the number of deaths related to prescription opioids. However, the greatest cost of pain rests on the individual who, in addition to his or her pain, is fraught with anxiety, depression, sleep disturbances, and deteriorating interpersonal relationships, resulting in a severely diminished quality of life. While efforts are continuing to unlock the environmental and intrinsic causes and contributors to pain, there are still a great number of unmet needs throughout the realm of pain management, including imaging, drug monitoring, objective pain assessment tools, and of course, therapeutic interventions. As the technological revolution of 21st century medicine continues its ascent, nanomedicine offers unprecedented opportunities in the development of novel pain assessment, diagnostic, and therapeutic delivery mechanisms that will address many of the global unmet needs in pain management, and change the frowning face of pain to a smile of relief. Successful integration of nanomedicine into the clinical milieu requires multi- and interdisciplinary collaboration from every facet, including healthcare professionals, engineers, scientists and researchers, government and regulatory agencies as well as academia.

Laparoscopic procedures have been associated to moderate or severe pain that may require opioids and almost all patients referred shoulder pain. Intraperitoneal instillation of local anaesthetics, as part of a multimodal approach analgesia program, reduces pain intensity and morphine consumption after laparoscopic cholecystectomy. However, direct local anesthetic instillation is not enough to eliminate visceral and shoulder pain. Heated and humidified gas may produce positive effects such as reduction of postoperative pain. Intraperitoneal nebulization, a new technique of drug administration, provides homogeneous spread of drugs allowing a better distribution of local anaesthetics throughout the peritoneum. This technique combines the effects of gas conditioning and the analgesic benefits of local anaesthetic instillation. Nebulization of local anaesthetics during different laparoscopic procedures reduced postoperative pain, morphine consumption and allowed earlier mobilization. Future studies should determine, the optimal dose of local anaesthetics, the effect of local anaesthetic nebulization in different clinical settings and its importance on long term clinical outcomes.

A correct long-term opioid therapy implies the selection of the appropriate opioid and dose for each patient, but it is well demonstrated that the “clinical” approach alone is not sufficient. To this purpose, the literature is stressing that physicians have to focalize even more their attention both on the pharmacokinetic and pharmacodynamic properties of the opioids and on the differences among patients, including the genetic background. Accurate and fast analytical methods (e.g. Tandem Mass Spectrometry) for detecting plasma opioid concentrations represent a useful tool for clinicians to prevent adverse reactions in selected patients. The detection of polymorphisms of several genes involved in opioid absorption, distribution, metabolism, and elimination are promising to customize pain therapy. The success of the chronic opioid therapy also depends on the other drugs co-administered, possibly giving origin to drug-drug interactions; the clinical outcome should be constantly monitored.

Chronic perineal pain syndrome caused by pudendal nerve, is caused by the nerve entrapment between the sacrospinous and sacrotuberous ligaments (interligamentous plane) at the ischial spine and in the Alcock’s canal. Pain therapists approach the problem with peripheral nerve blocks. Needle placement is done by a fluoroscopic, computed tomography (CT) or ultrasound (US) guide. The first is unable to visualize the interligamentous plane and it exposes the patient to potentially harmful ionizing radiations. CT scan allows the visualization of the interligamentous space and of Alcock’s canal, but it is lacking real-time visual control. US alone ensures real-time needle advancement and confirmation of injective spread within the interligamentous plane but it’s usually combined with intraoperative fluoroscopy because at the depth of the ischial spine (usually more than 7 cm) the resolution should be suboptimal. We tried to improve pudendal anesthetic block using fusion real time imaging between US and CT. The system combines, in real time, US imaging with previous magnetic resonance (MR) or CT data. Imaging fusion is possible through the identification of anatomical landmarks of the same patient obtained by the different imaging modalities. Fusion imaging could help to avoid multiple exposures to ionizing radiations, improving costs and quality. We decided to verify the potential of this technique, normally employed to guide interventional imaging, to peripheral anesthetic block, testing its feasibility.

Pain is the symptom that leads most patients to ask for medical intervention; if not controlled, pain may become a very costly item in the Italian Health Care system. Proper referral to a second level specialist pain center can extensively decrease the duration of a painful condition, prevent the onset of more pain and of the so-called pain syndromes, and also reduce the improper use of analgesic drugs or pain surgery. Patients should be referred to a specialist pain center when their pain is uncontrolled. In this observational study we analyzed the clinical and demographic data of a population referred for the first time to a specialist pain center (Fondazione Salvatore Maugeri, Pavia) in the year 2008 to define patient characteristics and to understand who makes referrals and after which kind of pharmacological and interventional treatment. Our results indicate that in Italy patients are referred to a pain center very late, which increases the duration of pain syndromes and the cost of pain management.

Local anesthetics and opioids are the most commonly used drugs in regional anesthesia. Several other drugs are used as adjuvants in addition to local anesthetics. We will review the drugs currently used in regional anesthesia. In April 2009 we searched the PubMed database and found 143 articles related to the clinical use of drugs in regional anesthesia; we divided them into 3 major chapters: local anesthetics, opioids and adjuvants. Among local anesthetics, ropivacaine and levobupivacaine can be considered the drugs of choice in neuraxial and peripheral techniques because their toxicity is low even in large volume administration; mepivacaine can be considered the drug of choice in peripheral techniques when a shorter blockade is needed. Sufentanil is the opioid of choice in both neuraxial and peripheral techniques because it appears to improve the quality of anesthesia and to prolong sensory blockade in the postoperative period. Among the adjuvants to local anesthetics, clonidine is by far the most used drug in regional anesthesia; its yield in improving and prolonging the effects of local anesthetics is apparent in neuraxial techniques. Other drugs have been studied as adjuvants to local anesthetics but clinical evidence of their benefit is controversial in many cases and further trials are unquestionably warranted. In conclusion, since many different drugs are available for regional anesthesia, we must choose wisely the one that exhibits the best safety-efficacy profile and that suits the chosen technique and type of anesthesia/analgesia best.

Chronic pain is a situation that bring patients to ask for a medical intervention and can be originated from many different pathologic conditions. Nowadays, recent advancements in pain treatment have made possible to control pain in many patients, allowing them to return to daily activities. Anaesthesiologists are the modern pain specialists, and must know and define the origin of pain in every case: the comprehension of pain mechanisms gives them the possibility for a planned strategy of treatment. In this work we perform a overview about the “state of the art” of pain treatment in Italy analyzing what are the problems that require to focalize our attention. Therefore, sometimes many visits are necessary for a correct diagnosis and successful therapy. Pain management is still a young speciality, and the Italian pain specialist is often a self made expert who needs proper structures and dedicated people: the result is a different treatment not only between the hospitals but also in the same pain conditions. Although it seems that many of the new techniques used to control pain are successful, few studies and controlled trials have been done to verify long-term efficacy and potential adverse effects.

The availability of new local anaesthetics and the improvement of regional techniques has caused a great increase of central and peripheral blockades for anaesthesia as well as for postoperative pain. The increase of these blockades tends to increase the rate of complications. In a Pubmed research we found more than 400 articles about this topic. In the analysis of the literature we divided two major chapters: severe complications after central blockades and after peripheral nerve blocks. Analysis of the literature showed a lower incidence of serious complications associated with neuroaxial anaesthesia. It is important to underline that authors stressed the importance of predisposing factors like pre-existing peripheral or central neurological disease, arteriosclerotic disease, osteoporosis and spinal stenosis, diabetes, cancer, chronic alcohol abuse and steroid therapy. Otherwise, the most concern about peripheral nerve blocks is nerve injury and/or neuropathy due to potential toxicity of local anaesthetics or due a nerve lesion for needle trauma or infection. Even if the incidence of severe side effects is rare, it is very important that we approach this technique knowing well the risks (even if low) so that we can prevent them improving the outcome of patients. Nevertheless, there is again the need to have a large prospective study to investigate the real incidence of severe complications of central and peripheral blocks.