Better consenting for thyroidectomy: who has an increased risk of postoperative hypocalcaemia?

[helvella]

How very right it is that patients should be assessed as well as possible, and that consent should be properly detailed and accurate.

The possibility of reducing further the risks is definitely a laudable aim.

Eur Arch Otorhinolaryngol. 2016 Dec;273(12):4437-4443. Epub 2016 May 20.

Better consenting for thyroidectomy: who has an increased risk of postoperative hypocalcaemia?

Harris AS1,2, Prades E3, Tkachuk O3, Zeitoun H3.

Author information

1 Betsi Cadwaladr University Healthboard, Clwyd, UK. [e-mail].

2 ENT Department, Glan Clwyd Hospital, Rhuddlan Road, Bodelwyddan, Rhyl, Denbighshire, LL18 5UJ, UK. [e-mail].

3 Betsi Cadwaladr University Healthboard, Clwyd, UK.

Abstract

Hypocalcaemia is the most common complication following thyroidectomy. This study aimed to establish the factors associated with increased risk of hypocalcaemia on day 1 following thyroidectomy. All patients who underwent thyroidectomy under a single consultant during a 5-year period were included. A multivariate analysis was undertaken to ascertain which variables had the most effect on the risk of hypocalcaemia. A prognosis table was constructed to allow risk to be predicted for individual patients based on these factors. Included in the analysis were 210 procedures and 194 patients. Eighty-two percent of patients had no calcium derangement postoperatively. Fourteen point nine percent were categorised as early hypocalcaemia, 1 % had protracted hypocalcaemia and 2.1 % had permanent hypocalcaemia. For hemi-thyroidectomies 2.8 % had postoperative hypocalcaemia and 0.9 % had permanent hypocalcaemia. The multivariate analysis revealed total thyroidectomy (risk ratio 26.5, p < 0.0001), diabetes (risk ratio 4.8, p = 0.07) and thyrotoxicosis (risk ratio 3.1, p = 0.04) as statistically significant variables for early postoperative hypocalcaemia. Gender as an isolated factor did not reach significance but was included in the model. The p value for the model was p < 1 × 10-12. Total thyroidectomy increases risk of early hypocalcaemia when compared to hemithyroidectomy. Gender, diabetes and thyrotoxicosis were also been found to influence the risk. All of these factors are available pre-operatively and can therefore be used to predict a more specific risk for individual patients. It is hoped that this can lead to better informed consent, prevention and better resource allocation.

KEYWORDS:

Hypocalcemia; Hypoparathyroidism; Informed consent; Postoperative complications; Risk; Thyroidectomy

PMID: 27207140

DOI: 10.1007/s00405-016-4084-4

ncbi.nlm.nih.gov/pubmed/272...

[SilverAvocado]

Since my thyroidectomy I feel a little touchy about consent. Ironically I was writing a journal article about consent just before the operation!

My experience was that before I gave my consent I was showered with information, given a lot of my surgeon's time, a special meeting in a more relaxed part of the hospital, a lot of detailed discussion of my situation, statistics and extra information looked up in journels, stories about the consultant's other patients. I wasn't surprised by this, as of course I knew that consent is considered a big deal, and there is lots of ethics and formality around it and how important it is.

What did surprise me is that after the operation when I was not responding well to thyroxine, there was nothing else similar. There was no extra information, no detailed discussion of my symptoms and experience, and certainly no looking up in books and journals for other solutions.

It really did make me think that there's something wrong with our model of consent if actually the consent process is being prioritised over the treatment process. All this wringing of hands and formality about it does not match the context of the medical care that's being offered, and the energy being put into the process is not matched by the energy to make people well.

This article is actually doing a similar distortion, I think. It's presenting a finding about predicting patient outcomes in terms of consent implications, when the paper isn't about consent in any way, it's about an issue that should be important for treatment.

[Clutter]

Helvella,

Interestingly I had hypocalcaemia after the hemilobectomy but not after total thyroidectomy. I was called back to the hospital the day after I was discharged to collect a prescription for calcium tablets because calcium results showed it was low. I didn't feel well enough for the 3 hour round trip so didn't bother. A calcium test a week later showed calcium level had self corrected.

Loss or damage to parathyroid glands causes hypocalcaemia and is a risk during hemi or thyroidectomy. I wasn't warned of this when asked for consent but was advised there was a 2% risk of damage to the vocal chords. I don't recall being advised of any other risks then or when I consented to total thyroidectomy 3 months later. As the thyroidectomy was due to thyCa found post-op after the hemi I would have assumed the operation risks to be smaller than the risk of thyCa spreading if I didn't have completion thyroidectomy.