Effects of Intravenous Morphine on Physical Examination Findings in suspected Acute Appendicitis: A Randomised Conctrolled Clinical Trial

Back ground: Use of analgesics in patients with undiagnosed acute abdominal pain is marked by long standing controversy over the effects of analgesia on physical examination findings. Analgesics are often with held for fear that they may mask physical examination findings and lead to delayed or missed diagnosis. This study aimed at determining the effects of intravenous Morphine on the physical examination findings in patients with clinically suspected acute appendicitis admitted at Mulago hospital Accident and Emergency Department and surgical wards of Mulago hospital.
Methods: This study was a randomized controlled clinical trial. Patients were randomized to receive intravenously either 0.15mg/kg (maximum 1ml) of morphine sulphate (n = 28) or an equal volume of water for injection (placebo) (n = 32).
Results: A total of 60 patients 28 males (46.7%) and 32 females (53.3%) aged between 7 years to 79 years with acute right lower abdominal pain suspected to be due to appendicitis were included in the final analysis. The study findings demonstrated that I.V morphine provided substantial and statistically significant pain reduction (P=.00) in patients with acute abdominal pain due to appendicitis without blunting their physical examination findings. Those who received placebo had fractional pain VAS reduction which were not statically significant (P = 0.610). Effects of I.V morphine and placebo on the rebound tenderness and muscle guarding showed that there was no statically significant change in these two important physical signs for both study groups.
Conclusion: The study has objectively demonstrated that when compared with placebo judicious administration of I.V morphine provides significant pain reduction without adversely affecting the physical examination findings in patients presenting with acute abdominal pain due to suspected appendicitis.