Introduction: The objectives of this study were: a) to evaluate the effectiveness of intraoperative intact parathyroid hormone (PTHi) determination as a marker of hyperparathyroidism resolution; b) to establish the minimum number of blood samples required; and c) to determine whether cervical manipulation increases baseline PTHi levels.
Patients and method: We performed a prospective study in 45 patients. Three intraoperative blood PTHi determinations were performed: at baseline and at 10 and 25 minutes after excising the lesion. To analyze the effects of cervical manipulation, in 19 patients, 2 further determinations were made after 2 minutes of massage on both sides of the neck. A decrease of > 50% in PTHi values between postexeresis samples and the baseline sample (gradient > 50%) was used as diagnostic and therapeutic criteria and normalization of calcemia was used as a criteria for complete resolution.
Results: Whenever the lesion causing hyperparathyroidism was extirpated, PTHi levels decreased at 10 and 25 minutes after exeresis. This decrease was predictive of complete resolution when the gradient was > 50. Cervical manipulation (massage) did not increase PTHi values. In patients with complete resolution, blood calcium levels also returned to normal.
Conclusions: 1. Intraoperative PTHi determination with a gradient > 50 is an excellent prognostic marker of resolution. 2. Only 2 PTHi samples are required: one at baseline and another at 10 minutes after exeresis. 3. Preoperative cervical manipulation does not increase PTHi values.