Constipation postoperatively is common. So too is the “have you moved your bowels today” catch cry from nurses everywhere. Many factors increase the risk for constipation in patients who have undergone a general anaesthetic.
Change in routine and diet, reduced fluid intake perioperatively, nausea and vomiting postoperatively, reduced mobility, pain, opioid medications and use and type of anaesthetic agents all have an effect on reducing gut motility increasing the risk for constipation.
Constipation is defined on the basis of stool frequency, stool consistency and difficulty passing stools. It is the accumulation of old hardened faces that is so tightly packed together that the bowel movements are infrequent and incomplete, causing much difficulty and strain, producing dry, hardened feces. The hardened feces will then stick to the walls of the colon and inhibit proper nutrient absorption.
Screening the patient prior to or on admission for chronic constipation is an important aspect to consider for minimising the risk for constipation. Ideally patients with a history of constipation should be flagged as high risk for developing constipation postoperatively.
Gathering information from the patient preoperatively is most likely to include their usual patterns of bowel movements, including the frequency, consistency, size or amount, and also amount or degree of straining when passing bowel motions.
A management plan could be implemented immediately paying very close attention to hydration perioperatively. Including the patient preoperatively in the development of their bowel management plan ensures that the patient has a voice in what works well for them. As part of developing the plan is patient education on risk factors which can exacerbate constipation.
Patients need to understand the importance of bowel movements in general and particularly postoperatively. Nursing staff can play a significant role in educating patients on appropriate level of fluid intake and the importance of moving and mobilising as much as possible. The use of the Bristol Stool chart is helpful in educating patients of appropriate stool consistency.
Postoperative nausea and vomiting (PONV) if not adequately treated can result in dehydration which impacts on fluid absorption and consistency of the bowel motion. Prolonged periods of fasting preoperatively has a similar effect if not adequately managed. The elderly are particularly vulnerable to perioperative dehydration.
Mobility restriction postoperatively due to type of surgical procedure performed and or pain adds an additional aspect impacting on constipation. Studies on the effects of physical activity in healthy subjects on colonic transit suggests accelerated transit time after physical activity . All patients should be encouraged to physically move as much as possible within the restrictions in place medically.
Optimising pain relief for mobility is a balancing act that is at times complex. Opioids reduce gastrointestinal propulsion and increases fluid absorption. Decreased mobility reduces gut motility. Ensuring the patient has the right amount of pain medication to maximise physical mobility is the goal here.
Medications may be used to assist in the prevention and treatment of constipation. Emollient stool softeners are easy to use and are best used prophylacticly in the short-term particularly for the patient receiving a postoperative opioid medication.
Many health professionals do not give bowel management the focus and the respect it requires. Constipation is uncomfortable and distressing for patients. Constipation postoperatively can lead to faecal impaction and gut obstruction which are possible serious consequences of untreated constipation.
Patient and staff education regards risks associated with constipation and how to prevent it postoperatively are the key to ensuring patients respond more often and with confidence “Yes my bowels have moved today thank you nurse”.