Respiratory depression following iatrogenic tramadol overuse in a patient with chronic renal failure

Abstract

Introduction Tramadol hydrochloride is a centrally acting analgesic drug that is widely used in the treatment of pain. It exhibits good analgesic efficacy and a potency comparable to codeine [1]. Besides its proven clinical efficacy, tramadol is a safe drug with few cardiovascular side effects; respiratory depression and drug abuse and dependency are of minor clinical relevance, unlike for some other opioids [2]. We describe a case of respiratory depression that ensued in a 69-year-old man with renal failure who was accidentally given a high dosage of tramadol during hospitalization. Case report A 69-year-old man (72 kg) was admitted to our hospital because of severe anemia (Hb, 5.7 g/dl) and melena. The patient had an 8-year history of hypertension. He suffered from chronic renal failure and had been undergoing dialy-sis treatment every other day, for 4 months. Fifteen days before admission, he received the last of four transfusions, because of severe anemia, likely due to kidney dysfunc-tion. Three months before admission, he was evaluated at our hospital, in the Infectious Disease Department, for back spondylodiscitis. Abstract We describe a case of tra-madol-related respiratory depression in a 69-year-old man, admitted to our hospital because of severe anemia and melena in the context of chronic renal failure and dialysis treatment. He complained of back pain due to spondylodiscitis, and analgesic therapy was established with tramadol (200 mg/day intravenously). The patient received a total daily dose of 400 mg tramadol because of a therapeutic mistake. The patient tolerated this dosage for about two days before experiencing symptoms of opioid overdose that disappeared after naloxone treatment. In contrast with other opi-oids, few cases of tramadol-related respiratory depression have been described, in patients with impaired renal function, as tramadol is mainly excreted by kidneys. This case report emphasizes the need to avoid tramadol overuse in patients with renal failure, who could experience side effects such as respiratory depression.