Evaluation of Six-Minute walk test in predicting post operative pulmonary complication in major abdominal surgeries- An Observational study

The study will be conducted on patients undergoing elective major abdominal surgeries. The written and informed consent will be obtained from all the patients.

One hundred and thirty-nine patients scheduled for elective major abdominal surgeries will be enrolled in this study.

A brief history taking would be done. History of known comorbidities, history of smoking, if a smoker the number of cigarettes per day, the number of years of smoking and the last smoking would be noted.

The six-minute walk test will be performed indoor along a flat surface in a straight corridor 30m long, with 180 degree turns every 30m near the pre-anesthesia clinic. The resuscitation and crash cart equipment will be made available.

The patient’s heart rate, oxygen saturation will be monitored throughout the test.

The patients would be monitored continuously for any adverse reaction throughout the procedure.

The ability of the patients to complete the test will be noted. If the patients are not able to complete the test, then the number of minutes, they are able to walk will be noted.

Patients posted for major abdominal surgeries will be premedicated with T. Alprazolam 0.25mg, T. Ranitidine 150mg and T. Metoclopramide 10mg, the night before surgery and on the morning of the surgery.

The patients posted for major abdominal surgeries will all be administered general anesthesia with epidural anesthesia. Patients in the premedication room will be monitored for the heart rate, blood pressure, oxygen saturation. Patients will be shifted to the operating room. Patients will be premedicated with Inj. Midazolam 0.01-0.02mg/kg and Inj. Fentanyl 2mcg/kg. Then induced with Inj. Propofol 2mg/kg and muscle relaxation with Inj. Vecuronium 0.08-0.12mg/kg. Patients will be intubated with endotracheal tube and depth of anesthesia would be maintained with 50% O2 and 50% N2O and 1 MAC Sevoflurane.

Epidural will be activated intra-operatively with levobupivacaine 0.25% 6-8ml and topped up every 2 hours with 3-6ml.

Patients will be administered Inj. Fentanyl 0.5mcg/kg every hour till the end of surgery. Relaxation will be maintained with vecuronium 0.01mg/kg.

Intra-operatively, the patient’s heart rate, blood pressure, respiratory rate, oxygen saturation will be monitored and noted.

At the end of surgery, patient will be extubated with Neostigmine (0.07 mg/kg) and glycopyrrolate (0.014 mg/kg).

Patient will be shifted to ICU for monitoring and epidural infusion.

Patients with be given 0.125% Levobupivacaine with Fentanyl 2mcg/ml epidural infusion @ 4-6ml/hour postoperatively.

The Patient is said to have post-operative pulmonary complications, if any of the following happens:

prolonged mechanical ventilation>48hrs

atelectasis (radiological diagnosis)

bronchitis

pneumonia

acute respiratory failure

Fall in oxygen saturation (<92% in Room air)

Patients requiring oxygen support >24hours.

Development of new history of cough with sputum production.

Persistent tachypnoea >30 for >24hours.

The results of the test would be documented.

The patients would be monitored for post-operative pulmonary complications during the hospital stay.

The criteria for ICU discharge are:

Patient should be pain free.

Hemodynamically stable.

Urinary catheter removed.

Patient started on orals.

The length of ICU stay for the patients will also be studied.

The patients would be followed up through phone call every week till 30days.

The correlation between smoking, age and weight and incidence of post-operative pulmonary complications will also be studied.