Medicine administration by oral, rectal, vaginal, topical and inhalation routes
Medicines are administered by various routes depending on the condition being treated, the desired site of effect and anticipated speed of effect. The intramuscular and intravenous routes have a rapid, system-wide effect and, by bypassing the stomach, avoid the potential risk of enzyme breakdown of drugs within the gastrointestinal system. Those given by other routes are absorbed more slowly. The ‘seven rights’ of drug administration must always be observed (Chapter 76).
The woman’s identity must be confirmed, drug allergies ascertained, and administration documented immediately. Self-administration of medicines is common in maternity care where the woman has been assessed as competent to do this and there are arrangements for safe storage of the drugs. Informed consent is essential and hands must be washed before and after giving any drug by any route.
Equipment includes drug chart, medicine to be administered, medicine pot or measure. An oral or medicine syringe is sometimes required for the administration of liquid medicines (Figure 75.1). Water to swallow should be provided.
This route is suitable where a rapid response to the drug is not required. It is not suitable for women who may have trouble swallowing or who are not fully conscious and alert.
The prescription must be checked to ascertain any specific instructions such as whether it should be given with food. Tablets must not be crushed or capsules broken. Sublingual preparations are placed under the tongue, buccal preparations in the buccal cavity.
Rectal administration produces a faster effect than oral and reduces nausea. It also reduces ‘first pass’ metabolism and increases the bioavailability of the drug. Suitable when the woman cannot swallow or where direct local effect is required such as in the treatment of haemorrhoids, constipation or steroids for the treatment of inflammatory bowel disease. Postoperative analgesics may also be given in suppository form. The notes should be checked to exclude a history of anal or rectal damage, surgery or disease. If present, the preparation should be withheld and medical advice sought. Under normal circumstances a digital rectal examination prior to insertion is unlikely to be required in midwifery practice.
Equipment includes the drug in suppository or liquid (enema) form, drug chart, water-based lubricating gel, absorbent pad, gloves and apron, clinical waste bag, tissue to wipe. A bedpan or commode will be needed if the aim is bowel evacuation and the woman cannot get up to the toilet. An explanation must be given. Verbal consent must be obtained. Attention to privacy, dignity and comfort is essential, with exposure kept as brief as possible. The midwife must explain what she is doing at each step.
Explain the procedure to the woman, the woman lies on her left side, with knees flexed and right knee higher than left (Figure 75.2), the midwife may be required to assist with this. The buttocks only are exposed and safely positioned close to the edge of the bed. The absorbent pad is placed under the buttocks. Hands are washed and gloves and apron put on. The buttocks are gently separated to expose the anus. The anal area is examined for abnormalities such as anogenital warts. For suppositories, apply lubricant, ask the woman to relax and breathe deeply and insert into rectum to a depth of 2–4 cm. The suppository should be inserted according to the manufacturer’s instructions. This is usually ‘pointed’ end first. There is limited evidence for insertion ‘blunt’ end first. Enemas should be warmed to body temperature and inserted with the tube well lubricated and air expelled from the pack. The container is slowly squeezed until empty. The woman should be gently cleaned and covered. She should be asked to retain the suppository or enema for as long as she can, if the purpose is to retain the medicine. The call bell should be given.
Topical medicines are applied directly to the affected area. Preparations of topical drugs include eye or ear drops, creams, lotions, gels and transdermal patches. When administering topical medications gloves must be worn. The skin is the largest organ in the body and readily absorbs drugs. Care must be taken to avoid over-dose of topical preparations such as steroids, which have significant side effects.
Common drugs given by the vaginal route in midwifery include preparations for treatment of vaginal infections and drugs for cervical ripening. They may be in gel or pessary form. Equipment includes sterile gloves, sterile vaginal examination pack, apron, absorbent pad, wipes, water-based lubricating gel, the drug and the prescription sheet. Informed consent must be obtained; attention to privacy, dignity and comfort are essential. The woman lies semirecumbent with legs flexed, ankles together and knees apart (Figure 75.3). The drug is inserted in accordance with the manufacturer’s instructions and local policy. The fetal heart must be auscultated and documented before and after the procedure.
Entonox® is the commonest inhaled drug in midwifery practice. Midwives must be trained in its use, including the associated health and safety risks. Oxygen is the second most common inhaled drug and is often used in emergency situations, given by face mask or nasal prongs (Figure 75.4). Oxygen saturation levels must be monitored. It is a powerful drug, which should be prescribed. In emergencies it is often given unprescribed and its use must be clearly documented. Staff administering oxygen must be trained in its use and aware of the risks associated with this highly explosive gas. Inhaled drugs, used to treat chronic and acute respiratory disorders, are rapidly absorbed through the respiratory endothelium. The commonest means of drug administration for conditions such as asthma is through aerosol delivery in the form of dry powder inhalers (DPI), metered dose inhalers (MDI) or nebulisers. The effect is dependent on the woman’s inhaler technique.
Inhalational administration of drugs is usually with the woman sitting upright or in a semirecumbent position.