Sensibility Of The Abdomen After Abdominoplasty
Authors: Fabio X. Nahas, MD, PhD, Andreia B. Farah, MD, Yara Juliano, MD, Neil F. Novo, MD
Decrease of abdominal skin sensibility is a very frequent problem after abdominoplasty. Although abdominal skin sensibility was studied after the use of the TRAM flap (1), it was not found in the literature a specific study about hypoesthesia secondary to abdominoplasty. The purpose of this paper is to find out which modalities of sensibility are decreased and which areas of the abdominal wall are affected, so that patients can be warned preoperatively about this condition.
Methods: Forty patients were divided in two groups of twenty patients each. On the control group, patients had no previous abdominal incisions. The sensibility evaluation of patients from the experimental group was made from 12 to 60 months after the operation, with average of 30.75 months. All patients had the abdominal skin divided into twelve areas (Fig. 1). Six modalities of sensibility were evaluated. Superficial touch was tested with the smooth touch of a cotton ball over the skin surface. Superficial pain was evaluated with a sharp object weighting 30 g. This object was placed 1 cm above the skin surface. Using the gravitational force, this device was released and, as it touched the skin, the sensibility to pain was observed. Hot temperature was tested with a glass containing hot water at 60º C, whereas a glass containing ice was used to test sensibility to cold temperature. Vibration was evaluated with a tuning fork with a frequency of 435 vibrations per second, placed over the abdominal skin. In these tests, data was recorded either as positive, if the patient mentioned that she felt any degree of stimulation or negative, if she was unable to feel it. Sensibility to pressure was measured using 16 loads with weights varying from 3.5g to 70g, exerting pressure from 0.50 gl/mm² to 9.90 gl/mm². The weights were attached to a stick by a string and were placed gently over the skin until there was no tension at the string. The patient was submitted to the pressure for 5 seconds with each weight and the threshold pressure felt by the patient was recorded.
Results: When the data obtained of superficial touch, superficial pain, temperature (hot and cold) and vibration of the control group was compared to the experimental group, it was found decreased sensibility of all modalities at area 8. It is important to stress that a remarkable number of patients referred a positive sensation to all tests (Fig. 2).
The sensibility to hot temperature showed a statistical significant difference also at areas 5 and eleven, although the main sensibility decrease occurred at area 8 (Fig. 3).
When the data of sensibility to pressure was compared on both groups, there was a statistical significant difference in all areas, although patients presented less sensibility in area 8 (Fig. 4).
Conclusions: These findings help plastic surgeons to orient their patients about possible risk of exposure to injuries in the areas with decreased sensibility after abdominoplasty. Most importantly, as these patients presented decrease of sensibility to pressure and hot temperature in a more extensive area of the abdomen, they will be more exposed to burn injuries after this operation.
Figure 1 - Areas studied at the abdomen
Figure 2 - Positive sensibility for superficial touch, pain, hot and cold temperature and vibration, tested at area 8 (Fisher test, p = 0.05)
* Statistical Significant Difference
Fig. 3 - Sensibility for hot temperature tested at areas 5, 8 and 11 (Fisher test, p = 0.05)
* Statistical Significant Difference
Fig. 4 – Average pressure on each area (Fisher test, p=0.05)
* Statistical Significant Difference
References:
1) Spear,S.,Hess,C. – Evaluation of abdominal sensibility after TRAM Flap Breast Reconstruction. Plast Reconstr. Surg. 106:1300, 2000