Griffiths et al modified the POSSUM score for patients undergoing head and neck surgery. The authors are from the University Hospital of Wales in Cardiff.


Operative Severity


endoscopy; tracheostomy; lymph node biopsy; excision of submandibular gland


parotidectomy; thyroidectomy; neck dissection for lymph nodes


laryngectomy; pharyngectomy


free flaps; pedicled flap



X for morbidity from POSSUM score =

= (0.16 * (physiologic score)) + (0.19 * (operative score)) - 5.91


Y for mortality from POSSUM score =

= (0.13 * (physiologic score)) + (0.16 * (operative score)) - 7.04


Z for mortality from P-POSSUM score =

= (0.19 * (physiologic score)) + (0.15 * (operative score)) - 9.37


Additional variables included in the analysis (all associated with increased post-operative complications):

(1) radiotherapy

(2) previous surgery

(3) malnutrition



• The POSSUM score was valid for predicting morbidity, and it performed better for high risk patients.

• Neither the POSSUM nor P-POSSUM score performed well for predicting mortality. There was a tendency to overestimate the mortality rate, especially for low risk patients.


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