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.