Can the use of intraoperative intact parathyroid hormone monitoring be abandoned in patients with hyperparathyroidism?

Background

Ultrasound (US) and technetium-99m sestamibi scintigraphy (MIBI) are used to determine the localization of abnormal glands in cases of primary hyperparathyroidism (PHPT). Intraoperative intact parathyroid hormone (iPTH) monitoring is a reliable examination used to cure PHPT. The aim was to assess the necessity of intraoperative iPTH monitoring.

Methods

Sixty patients were examined using preoperative MIBI and US. iPTH was measured at 3 time points: (1) at the start of surgery; (2) 10 minutes after gland resection; and (3) more than 60 minutes after surgery. We defined a decreased iPTH level as an iPTH measured 10 minutes after resection that was less than 50% of the preoperative level.

Results

The iPTH of 55 patients with concordant lesions decreased to within the normal range more than 60 minutes after surgery.

Conclusions

It is not necessary to monitor intraoperative iPTH when single concordant lesions are preoperatively identified on both MIBI and US.     

Is intraoperative parathyroid hormone assay mandatory for the success of targeted parathyroidectomy?

BACKGROUND: Minimally invasive parathyroidectomy has become the first surgical option for patients with primary hyperparathyroidism (HPT) in many places. Preoperative localization studies are mandatory, and the use of a quick parathyroid hormone (PTH) assay is highly recommended. The aim of this study was to analyze our initial series of targeted parathyroidectomies. STUDY DESIGN: In a 2-year period, 50 patients underwent unilateral neck exploration for HPT under local anesthesia and light sedation. After biochemical diagnosis, a technetium 99m sestamibi scan was performed on all patients, and cervical ultrasonography was obtained in some patients. Frozen section analysis was used to confirm parathyroid tissue in all patients. There was no biochemical intraoperative evaluation of PTH. Demographics, surgical details, results, and complications were analyzed. RESULTS: There were 35 women and 15 men, with a mean age of 56 years (range 23 to 85 years). Mean preoperative calcium was 11.4 mg/dL (range 10.0 to 14.8 mg/dL), and PTH was 342 pg/mL (range 105 to 2,231 pg/mL). Mean surgical time was 52 minutes (range 30 to 100 minutes), and mean hospital stay was 2 days (range 1 to 7 days). Mean parathyroid weight was 1,000 mg (range 117 to 17,000 mg). Sestamibi scan correctly localized the abnormal gland in 47 patients (94%). There was one postoperative complication (bleeding); two patients required contralateral exploration, and persistent hypercalcemia developed in one that required surgical reintervention. After a mean followup of 12 months (range 3 to 25 months), all patients were normocalcemic. CONCLUSIONS: Targeted parathyroidectomy is safe and effective. Despite the fact that quick intraoperative PTH assay was not used, the cure rate was 98%.     

Flow measurements: Can several “Wrongs” make a “Right”?

AIMS: Although measurement of maximum flow rate (Qmax) is a standard and straightforward test, it is often difficult to obtain reliable readings. We obtained multiple measurements using a simple home uroflow device which categorizes Qmax into ranges. We hypothesize that the average of a series of relatively coarse measurements of Qmax would be more repeatable and therefore more representative of an individual's voiding function than a single, albeit more precise measurement. METHODS: We studied 22 male volunteers with a wide range of Qmax. They were asked to record flow category (<10 ml/sec; 10-15 ml/sec; 15-20 ml/sec; >20 ml/sec) and voided volume twice daily for 12 days using the home flow device. In addition, a clinic-based flow recording using a spinning-disc uroflowmeter was obtained at both the start and the end of the 12-day period. RESULTS: Good agreement between mean home flow and mean clinic flow was seen with mean (SD) difference of 1.3 (5) ml/sec. The mean for consecutive halves of an individual's home flow data showed excellent agreement (-0.2 (1.3) ml/sec). The two clinic readings showed poorer agreement (2.3 (6.8) ml/sec) than the home readings, and poorer agreement even than between clinic and home flows. CONCLUSIONS: Although simple in design, the home flowmeter actually shows greater accuracy than might be expected when used repeatedly to study the flow rates of men. Simple flow devices such as this could be used in conjunction with voiding diaries to give a more representative picture of patients' day-to-day voiding function.     

How low is too low? Intraoperative parathyroid hormone decline in normohormonal primary hyperparathyroidism

BackgroundIn normohormonal primary hyperparathyroidism, parathyroid hormone levels are normal but inappropriately elevated for the degree of hypercalcemia. The study goals were to determine intraoperative parathyroid hormone parameters predictive of (1) cure and (2) hypocalcemia in this subgroup.MethodsWe performed a retrospective cohort study comparing patients who underwent parathyroidectomy (2002–2019) for normohormonal and classic primary hyperparathyroidism. The primary outcomes were cure (calcium <10.3 mg/dL) and hypocalcemia (≤8.4 mg/dL) ≥6 months postoperatively.ResultsIn the study, 127 of 1,087 patients (11.7%) had normohormonal primary hyperparathyroidism. The groups experienced similar rates of cure (91.3% vs 94.1%, P = .23) and hypocalcemia (3.9% vs 2.9%, P = .53). However, intraoperative parathyroid hormone decline in cured patients was lower in those with normohormonal primary hyperparathyroidism (66.4% vs 84.5%, P < .0001). Receiver operating characteristic curves provided Youden’s indices of 52% and 75% (cure) and 75% and 88% (hypocalcemia) for patients with normohormonal and classic primary hyperparathyroidism, respectively. Cure rates with ≥50% intraoperative parathyroid hormone decline were similar (94.1% vs 95.0%, P = .72), but hypocalcemia was more prevalent in patients with normohormonal primary hyperparathyroidism and ≥70% intraoperative parathyroid hormone decline (10.4% vs 3.3%, P = .01).ConclusionIn patients with normohormonal primary hyperparathyroidism, intraoperative parathyroid hormone declines of ≥50% and ≥70% were predictive of postoperative cure and hypocalcemia, respectively. These parameters may inform intraoperative decision making and postoperative management.     

Will directed parathyroidectomy utilizing the gamma probe or intraoperative parathyroid hormone assay replace bilateral cervical exploration as the preferred operation for primary hyperparathyroidism?

The trend toward limited exploration for primary hyperparathyroidism (1 degrees HPT) has stemmed from advances in sestamibi scanning, gamma probe technology, and intraoperative parathyroid hormone monitoring (iPTH). Prior to widespread application, directed parathyroidectomy must be shown to meet the high standards of conventional cervical exploration. In this prospective, nonrandomized trial, results of parathyroidectomy utilizing the gamma probe, iPTH, or neither technique were evaluated. Altogether, 150 patients underwent parathyroidectomy utilizing the gamma probe (n = 50), iPTH (n = 50), or neither technique (n = 50). Each group was evaluated for operating time, length of hospitalization, cure rate, morbidity, mortality, and cost. A telephone survey was conducted with 25 patients in each group (n = 75) to address patient satisfaction. The gamma probe localized the abnormal gland in 66% of patients and confirmed cure intraoperatively in 84%. In the iPTH group, a more than 50% decrease from baseline occurred in 98%. The mean operating times were 76, 84, and 90 minutes, respectively (p = 0.16); and the mean length of hospitalization was 1 day. The biochemical cure rates were 98%, 100%, and 96%, respectively (p = 0.17). Total costs were $4476, $3918, and $3905, respectively. A total of 96% of patients in all three groups were "very satisfied" with their surgical procedure. Directed parathyroidectomy utilizing the gamma probe or iPTH assay does not significantly alter the operating time, length of hospitalization, cure rate, morbidity, mortality, or patient satisfaction when compared to conventional exploration in our practice. The probe is more expensive and was not a consistently reliable tool for localizing parathyroid pathology. PTH monitoring reliably predicts cure intraoperatively.     

Is It Possible to Create a “Mechanical” Arteriovenous Fistula in Hemodialysis Patients?

Manual suturing still remains the best technique for the creation of vascular anastomoses on uremic patients with excellent results, despite being time consuming, difficult to perform with small vessels, and associated with a significant learning curve. We created a full mechanical arteriovenous fistula on a 65‐year‐old uremic patient with a new device already used in cardiac bypass surgery. The fistula was created automatically and rapidly, without the need for temporary occlusion of the artery, reducing the risk of blood clotting. We believe that mechanical devices may be useful to produce precise and fast anastomoses requiring minimal training for the surgeon.     

“Turn downs” in aortic emergencies: Reassurance or uncertainty?

“Turn‐down” rate has been reported to have a significant influence on outcomes, and being turned down for an operation is associated with significant short‐term mortality risk. A study examining the impact of the pandemic on the “turn‐down” rates of acute aortic syndromes in the United Kingdom reported an overall “turn‐down” rate of  7.3% in the early part of the pandemic. This review examines the significance of “turn‐downs” in this setting and scrutinizes the adequacy of reporting this complex variable.     

Does low-energy helium-neon laser irradiation alter “in vitro” replication of human fibroblasts?

Cultured human fibroblasts were treated in a controlled, randomized manner to assess the effect of low-energy (0.9 mW) helium-neon (HeNe) laser irradiation on cellular proliferation. Two trials were performed: one with fibroblasts in the third to fourth passage and the other with fibroblasts in the 13th to 14th passage. In each trial, separate plastic petri dishes were inoculated with the cells, maintained in a 5% CO2-95% air atmosphere, and nourished with HB 102 media. Treatment began 48 h after inoculation with daily 60-s irradiations of the "treated" cultures over a 5-d period. Control cultures underwent the same handling but were not irradiated. A significant stimulative, or inhibitive, effect on replication was not found in either trial.     

Ethical Issues in DialysisAlan Spital,Series Editor: Do Not Resuscitate Orders and Iatrogenic Arrest During Dialysis: Should “No” Mean “No”?

An iatrogenic arrest is a cardiopulmonary arrest induced by a therapeutic effort. Frequently cardiopulmonary arrests during hemodialysis (HD) are iatrogenic. In this article I consider the question of what to do when a cardiopulmonary arrest occurs during HD in a patient with a do not resuscitate (DNR) order. I consider and reject four arguments to override the DNR order: the principle of nonmaleficence, the efficacy of resuscitation, proximate cause, and physician error. Instead, I argue that respect for patient autonomy and patient goals means that DNR orders must be respected unless there is compelling evidence that overriding the DNR would be consistent with the patient's goals. If such evidence is lacking, the physician has no moral choice but to follow the DNR order literally. As such, nephrologists need better communication with their patients regarding advance care planning and better documentation of their communication once it has occurred.     

Intensive Hemodialysis: Normalizing the “Unphysiology” of Conventional Hemodialysis?

Interest in intensified hemodialysis (HD) regimens is increasing internationally, as there is growing evidence that they are associated with improved outcomes. Appreciation that conventional hemodialysis (CHD), delivered as 4-hour sessions three times a week, is not providing optimal physiological replacement of renal function has led to the development of intensified dialysis therapies. These include long intermittent hemodialysis typically lasting 6-8 hours and delivered three times a week, short daily hemodialysis, providing more frequent sessions 4-7 days a week lasting 2-3.5 hours, and nocturnal hemodialysis, performed 5-7 days a week for 6-8 hours. Studies evaluating outcomes from these programs have indicated superior results to those achieved with CHD, including favorable modifications of cardiovascular risk factors and improvements in a variety of clinical measures. The objective of this review is to present available evidence supporting the hypothesis that in an attempt to provide a "more normal physiology," intensified HD regimens achieve outcomes superior to those historically achieved with CHD.