There are 2 types of intra-vascular fluids: blood (haemorrhage, epistaxis, menstruation) and lymph. Blood is the most often encountered intravascular fluid. Blood of epistaxis is not an impurity but must be washed away immediately. Fresh blood (venous or arterial) is not am impurity and but must be cleaned away with water. It does not require repeating ablution.

Modern medical procedures, diagnostic and therapeutic, involve dealing with blood. Phlebotomy is one of the commonest procedures in medicine. Venepuncture for diagnostic or therapeutic purposes is more common than operations on arteries. Lymphatic channels are rarely operated on. Surgery and catheterization also involve dealing with blood. Fresh blood is not an impurity when in the body.

2.0 INTERSTITIAL SPACE FLUIDS

Membranous cavities have various secretions. Pleural, peritoneal, pericardial, and synovial fluids are not impurities and must be washed away if they are outside their respective cavities. Diagnostic and therapeutic procedures are carried out involving pleural, peritoneal, pericardial, cerebro-spinal, synovial, and amniotic cavities or spaces. The fluids and effusions are generally not considered impurities.

3.0 PATHOLOGICAL SECRETIONS

Introduction: Pathological secretions are not generally considered impurities but should be washed away quickly to prevent infection.

Respiratory tract: Respiratory infections are associated with discharges. The common cold is a viral infection associated with nasal stuffiness, sneezing, and running nose. Sinusitis is the inflammation of the mucosal lining of the sinuses due to viral or bacterial infection and may be purulent. Pharyngitis is viral or bacterial inflammation involving the mucous membranes of the naso-pharynx, the uvula, and the soft palate. Otitis media is inflammation of the lining of the middle ear and could be accompanied by perforation of the ear drum. It is associated with other upper respiratory infections. Cough accompanies many respiratory infection. It is forcible expulsion of air from the lungs accompanied by expulsion of secretions that might have accumulated.

Genito-urinary tract: Urethritis is inflammation of the inner lining of the urethral duct. Cystitis is inflammation of the bladder. Pyelonephritis is inflammation of the kidney. Prostatis is inflammation of the prostate. Sexually transmitted diseases include syphilis, gonorrhea, herpes simplex, venereal warts, and lymphogranuloma venereum.

Gastro-intestinal tract: The commonest discharges in GIT infection are diarrhea and vomiting. Diarrhea is defined as excessive, frequent, and loose stool discharge. It may be due to infection, malabsorption, over-eating, drugs, or toxins.

GIT infections present as diarrhea. Cholera due to Vibrio Cholerae presents as vomiting and diarrhea typically described as rice water stool. E. Coli causes diarrhea described as watery, yellow, without blood or mucus. It may be associated with vomiting. Salmonella spp causes a diarrhea described as loose, watery, and with blood and mucus. Shigella causes diarrhea described as watery stools containing mucus and blood. Viral gastro-enteritis presents as vomiting and diarrhea. Cholecystitis presents as diarrhea and vomiting.

Vomiting (emesis) is forcible ejection of stomach contents from the mouth. It may or may not be accompanied by nausea. Vomiting is controlled by 2 centers in the medulla oblongata: the vomiting center and the chemo-receptor trigger zone. The vomiting center responds to sensory stimuli from various parts of the body. The chemoreceptor trigger zone is stimulated by drugs and toxins and it in turn stimulates the vomiting center to initiate vomiting.

Wounds represent an interruption in the continuity of skin. In open wounds the skin or mucous membrane has been broken exposing internal structures to environmental pathogens or toxins. In closed wounds the surface coverings remain intact protecting the damaged tissue from environmental hazards. Both open and closed wounds are liable to infection with the former being more likely.

4.0 INVASIVE PROCEDURES

Intubation: Esophageal, gastric, and naso-gastric tubes are inserted for diagnostic or therapeutic purposes. The fluids involved are not impurities but must be washed away to prevent their becoming nidi of infection. A tracheostomy tube may be inserted in cases of respiratory distress and respiratory secretions may accumulate in it. These secretions are not impurities.

Catheterization: Catheters can be introduced into the heart and the bladder for diagnostic or therapeutic purposes.