FITOFÁRMACOS Y PLANTAS MEDICINALES EN LA SEGURIDAD DEL PACIENTE QUIRÚRGICO/PHYTOMEDICINES AND MEDICINAL PLANTS AND PATIENT SAFETY IN SURGERY

INTRODUCCIÓN

Nature has been an important source of compounds that are currently used in the clinic or as tools to probe biological functions. In addition, medicinal plants or products derived from them are included in numerous systems of traditional healing. Nowadays, despite the use of synthetic drugs as the mainstream pharmacological resource to treat health problems, there is an increasing consumption of herbal medicines all around the world. Among the reasons for that, the high cost of synthetic drugs, the lack of access to medical, and pharmaceutical care and the widespread trend of seeing natural products as healthy and safe options have been mentioned.

The majority of the herbal medicines are over the counter drugs or homemade remedies, which are incorporated into self-care practices, in general along with synthetic prescription drugs. However, commonly patients do not notice the health professionals about that. This scenario is favorable to adverse events because although herbal medicines can be helpful to patients they also may cause side effects and be involved in drug interactions, as any other pharmacologically active agent, therefore needing medical supervision.

Interaction between phytomedicines, medicinal herbs, and conventional medicines may result in higher rate of bleeding, excessive central nervous system depression, hypoglycemia, hypotension, procedure-related infection, digoxin toxicity, anti-cholinergic effect and many others. The main groups of drugs reported to interact with herbal medicines are central nervous and cardiovascular acting drugs; anticoagulant, antiplatelet, antiretroviral agents and systemic antibiotics. This could be particularly relevant in conditions associated with high morbidity as surgery procedures, for example.

Anesthesiologists and surgeons must be familiar with the effects of herbal medicines and should specifically enquire about the use of herbal medicines during pre-operative assessment. It has been suggested that all herbal medicines should be ceased 2 weeks before the surgery. Nevertheless, several studies have shown that the use of alternative medicine supplements, including herbal medicines, by presurgical patients is prevalent (Table 1), and physicians seem to be poorly informed about these therapies. Furthermore, in many cases patients who were taking one or more herbal related agent did not report this information when asked about it during anesthetic assessment. Some of these agents have the potential to cause serious drug interactions and hemodynamic instability during surgery (Table 2). Therefore, it may be essential to identify patients self-administering these medications, during the preoperative period. Documentation of the use of these products is critical to determine the potential of drug or anesthetic interactions in the perioperative period.

By the year 2007, herbal medicine revenue in Brazil earned US$160 million (10), and Brazilian ethnobotanical studies reveal the disseminated folk use of plants with medicinal purposes. Furthermore, the government included phytotherapy in the public health system. Despite this picture, as far as we know, only one study on use of phytomedicines by surgical patients was carried out in Brazil (1).

Considering all discussed above, we designed a cross-sectional observational study aiming at estimating the prevalence of phytomedicines, medicinal herbs and other plant-derived products use among surgical patients in a tertiary reference academic general hospital (Porto Alegre - Brazil). The anesthetist's knowledge and attitude regarding the subject it will also be surveyed. From this, we intend to identify if patients are exposed to potential risk of intraoperative and/or postoperative complications due to the consumption of herbal medicines as well create awareness among clinical anesthesiologists regarding the use of these therapeutic resources. The study has the approval of the Hospital Ethical Committee, which is attached to the National Ethical Committee (CONEP).

Information will be obtained by means of structured interviews. The patients and anesthetists interview guides will be validated through a pilot action. Patients (N=340) presenting for preoperative clinic evaluation will be invited by one of the researchers enrolled in the project to participate and, if they agree to do so, they will read and assign a Term of Consent. The interviews will be voice recorded in order to establish a more confident connection between the interviewer and the interviewed. The sample size was calculated by using the software WinPEPI®, by Brixton Health, considering a prevalence estimated of 30%, desistence rate of 5% and a maximal error of 5%. The confidence index is 95%. The anesthetists (and anesthesiology residents) sample size was based on the current Hospital staff. Out of 85 anesthetists and 10 3thyear residents, 70 anesthetists and 10 residents will be interviewed after assigning a Term of Consent. The data will be organized using Microsoft Excel ®, by Microsoft and analyzed using SPSS Statistics ®, by IBM.

This study might constitute a start point to delineate local patient and health professional educational programs to improve the surgical patient's safety by considering the herbal medicines consumption as a relevant finding.

Conflict of interests

Authors have declared no conflict of interests

References

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