May predictors of difficulty in thyroid surgery increase the incidence of complications? Prospective study with the proposal of a preoperative score
Background: Although thyroidectomyisoneofthemostcommonsurgicalproceduresperformedworldwide,
some permanentcomplications,despitetheconsiderablyreducingincidence,mayaffectdramaticallythepatients
quality oflife.Thepurposeofthisstudyistoevaluatewhetherfactorsidentifiedpreoperativelyandexpressedina
score couldbepredictorsofmajorsurgicaldifficultyduringtotalthyroidectomyandinfluencetheincidenceof
complications.
Methods: A totalof164patientswhounderwenttotalthyroidectomywereexamined.Foreachpatientwe
calculated apreoperativescore,includingsevenparameters,whichweevaluatedtobepredictorsofdifficultyin
thyroid surgery,thatis,sex,bodymassindex(BMI),necklength,neckextension,thyroidglandvolume,thyroiditis,
and increasedparenchymalvascularization.Theoverallscorewasalsocomparedwithperi-andpost-operative
factors describingobjectivelythedifficultyinthyroidsurgery.Thesefactorsarethedurationoftheoperation,the
length ofhospitalization,theincidenceofcomplicationssuchashemorrhage,hypoparathyroidism,andrecurrent
laryngeal nerveinjuries.
Results: Therewasnostatisticallysignificantassociationbetweenourscoreandeitherthepercentageof
postoperativecomplicationsorthelengthofhospitalization.Theoperativetimewastheonlyvariableremarkably
associatedwiththescorevalue(p < 0.00001).Comparingthedurationoftheoperationwitheachofthepreoperative
predictivefactors,wefoundthatnoneofthefactorsreachedthevalueofstatisticalsignificance,butacloseassociation
couldbenotedwiththethyroidvolumeandtheBMI.
Conclusions: In ourstudy,predictorsofdifficultyinthyroidectomydidnotaffectmorbidityrates,assuggestedby
previousstudies,butonlyoperativetimes,whichweresignificantlyincreasedinpatientswithhigherscore.Although
ourresultshavelimitedstatisticalsignificance,theyallowustoconfirmthefundamentalroleofasystematicuseof
opticalmagnificationandmicrosurgicaltechniqueinthyroidectomy.Furtherstudies,withalargercohortofpatients,
areneededtovalidateourresultsandtoformulateauniversallyacceptedpredictivescoreofdifficultyin
thyroidectomypreoperatively.