Effect of Postoperative Girdle Following Abdominal Surgery on Pulmonary Function, Mobilisation and Postoperative Pain

Presently, there is a significant lack of knowledge in everyday surgical practice concerning treatment for incisional hernias and treatment with a corset before and after surgery or as a means of conservative treatment. For many years, corsets have been used in surgical departments without evidence to support this practice.

Corsets are expensive and require good patient compliance. Some arguments for the use of corsets are reduced pain and tension in the abdominal wall and prevention of the development and recurrence of incisional hernias, as well as their use as a truss in cases where conservative treatment is decided on.

The aim of this project is thus to ameliorate the lack of knowledge surrounding corset use.

More specifically, the aims of the project are to clarify the effects of corset use on

1. Physiological parameters

• Measured with spirometry, Vital capacity (VC), Forced Expiratory Volume (FEV), Peak Expiratory Flow (PEF) and with coughPEF

1. Patient comfort, pain and self-perceived experience

• Measured with VAS scale for pain. VHPQ (ventral hernia pain questionary) for pain. Recording of medication. Grade of mobilisation.

Corset treatment has been thought to affect cardiovascular and respiratory function as well as intra abdominal pressure both in positive and negative directions. There are no scientific publications that specifically describe and evaluate these effects. One reason for this could be that the assessment of such parameters is difficult and time-consuming in clinical practice, for instance spirometry. Less complicated alternatives e.g. Peak Expiratory Flow rate (PEF) has been considered too imprecise. However, recently, a simpler and more efficient instrument has been developed for measuring lung function, the Peak Cough Flow (PCF). It has been validated for use in pulmonary function testing in patients with neuromuscular disorders, where it is used to predict the risk of an inadequate coughing response and mucus clearance. Moreover, portable digital spirometers have been developed that can be easily used in an ambulatory setting. Postoperatively, similar problems may arise with a reduction in vital capacity. It is therefore important to investigate the effects of corsets on lung function.

Many patients that undergo laparotomy have an indwelling urinary catheter during the first postoperative days, often as a result of epidural anaesthesia but also for monitoring of fluid balance. A urinary catheter also allows for the measurement of the intra abdominal pressure, which, together with the measurement of systemic blood pressure, gives a good estimate of physiological parameters which can be used to compare different treatment groups.

A randomised controlled study concerning the postoperative use of corsets after laparotomy.

Hypothesis: Postoperative corset-use improves respiratory physiology as measured using the PCF without impairing other spirometric parameters. Corsets also reduce pain and discomfort after surgery.

Consecutive patients undergoing laparotomy at the Centre for Gastrointestinal surgery at the Karolinska University Hospital are asked whether they would accept to participate in a randomised study where one arm receives a corset for five days postoperatively and the other does not receive a corset after laparotomy. The primary end-point is PCF change, secondary end-points are vital capacity, residual volumes and patient perception as measured by the VHPQ. A GCP-trained research nurse with extensive experience will be in charge of monitoring and collection of data. PCF will be measured using a portable PCF apparatus (Peak flow meter, HS Clerment Clarke International) whereas other spirometric parameters are measured using a portable computer-assisted vitalograph (IM-Medico ML 2525). Pain and the functional status of the patients will be measured using the VHPQ as described above and the EuroQoL.

Based on previous measurements, a normal PCF without corset is assumed to be around 360ml/min. Assuming that the standard deviation is 40ml/min and that the corset improves performance by 10%, 21 patients will be required in each group (42 in total) at 95% significance level and power of 80%. In order to compensate for patient drop-out, we plan to include 50 patients. If intra abdominal pressure rises above 28cmH2O or if there are signs of wound infection, the corset will be removed. The wound will be photographed on day five in all patients.