Overview of Postoperative Pain Control
Managing pain after surgery is crucial for helping patients return to their normal life smoothly. In the past, pain after surgery was typically treated with opioid painkillers. However, due to the increase in problems related to the misuse of these drugs, there is a growing need for new pain management strategies that use a variety of methods.
Pain perception is very subjective, which makes managing pain quite challenging. Also, specific pre-existing conditions and social factors can make patients more prone to experiencing increased pain.
About 75% of patients experience pain after surgery, which is often moderately to severely painful. Less than half of these patients report having enough relief from their post-surgery pain. This is a major concern because if the pain after surgery is not managed properly, it can lead to negative health effects right after the surgery, and increase the risk of developing long-term pain related to the procedure. Between 2% to 10% of adults experience severe ongoing pain after surgery.
One of the major challenges in managing post-surgery pain is the lack of clear guidelines on how to monitor pain levels or intervene to adjust treatment to provide better pain relief.
Anatomy and Physiology of Postoperative Pain Control
The sensation of pain is carried by nerve pathways. Pain after surgery can be sorted into three categories: nociceptive, inflammatory, or neuropathic. Nociceptive pain is felt when specific nerves are activated, usually by something harmful like a surgical cut. Inflammatory pain happens when these nerves become more sensitive due to inflammation, which can cause symptoms such as pain, warmth, redness, and swelling. This type of pain typically lasts a few hours or days and can be reversed. Neuropathic pain is caused by damage to the nerves themselves and you feel pain because the nerve becomes more sensitive. This kind of pain can start shortly after surgery and may become a long-term issue.
Post-surgery pain can also be described as somatic (body) or visceral (internal organs). The somatic type of pain comes from nerves in the skin or deep tissue. These nerves send information quickly, and this results in a sharp, localized pain. The visceral type of pain is carried by slow-conducting nerves that cover many internal organs and join together before reaching the spinal cord. These nerves also get close to groups of nerve cells (autonomic ganglia) before entering the spinal cord. These features of visceral nerves contribute to a pain that’s spread out, hard to pin down, and might come with changes in heart rate or blood pressure.
Therapies for managing pain aim to stop the pain signals by multiple methods. This could include blocking the activity of pain receptors or stopping the production of substances that cause inflammation.
Why do People Need Postoperative Pain Control
Managing pain after surgery in a way that considers each patient’s individual health issues and personal circumstances can lead to several benefits. These include the patient needing to take fewer strong painkillers (opioids), staying less time in the hospital, experiencing less anxiety before surgery, and asking for fewer sleep-inducing medications. This approach is all about the doctors understanding and responding to each patient’s unique needs for the best recovery possible.
When a Person Should Avoid Postoperative Pain Control
There are certain medications that doctors use to control pain after surgery. However, these medications can’t be used if the patient is allergic to them. If the patient has a known allergy to these medications, it could cause harmful reactions. It’s also crucial to note that a specific group of medicines known as Nonsteroidal Anti-inflammatory Drugs (often referred to as NSAIDs) should not be used in patients who have had a particular type of heart surgery called a coronary artery bypass graft. This type of heart surgery involves grafting, or attaching, a healthy artery or vein from the body to the blocked coronary artery, allowing the blood to bypass the blocked portion. This is because NSAIDs can increase the risk of heart-related problems in these patients.
Equipment used for Postoperative Pain Control
Here are the materials and devices used by doctors for methods that help control pain after surgery:
- Medical equipment to access your veins (Peripheral intravenous or IV access)
- Cleaning materials for sterilizing the skin
- Sterile area for the procedure
- Devices to monitor your vital signs such as heart rate, oxygen levels, and blood pressure
- Equipment for emergencies – oxygen supply, devices for clearing your airway, suction, emergency medicines, and a defibrillator for resetting your heart rhythm in case of an emergency
- Ultrasound machine, which is used to capture images of the insides of your body
- Anesthetic drugs or medicines to reduce or block pain
- Different types of hollow needles used for delivering anesthesia. Their size, shape, and length changes depending on the type of anesthesia used
- Catheter assembly, which is a thin tube medical doctors put into a large vein to give medicines or fluids
- Peripheral nerve stimulator, a device used to determine nerve location for anesthesia.
What doctors use when setting up machines which let patients control their own pain medication (patient-controlled analgesia pumps) include:
- Medical equipment to access your veins
- The actual patient-controlled machine
- IV tubes filled with saline, a liquid doctors use to clean wounds or mix with certain medicines
- Carbon dioxide detector cannula, a device to monitor your breathing
- Narcotic drugs or strong pain medications
Tools used to determine if your pain control is working well:
- Visual analog scales
- Heft-Parker visual analog scale
- Verbal rating scale
- Numerical rating scale
- Faces pain scale
- Wong-Baker faces pain rating scale.
These are all tools that you rank your pain on, and it helps your doctor understand how much pain you’re experiencing.
Who is needed to perform Postoperative Pain Control?
After surgery, it’s important to manage any discomfort or pain you might feel. This is best achieved when a variety of professionals work together to create a personal plan for you. The team may include your regular doctor, a drug expert (pharmacist), the surgeon who did the operation, the anesthesiologist who helped you sleep during surgery, and the nurses who helped during and after surgery. Depending on your medical history and the type of surgery, there could also be a pain specialist, a physical therapist (someone who helps you move better), or a psychiatrist (a mental health professional).
Lately, many healthcare centres have started special groups focused on managing pain after surgery. They’ve also introduced recovery programs to monitor your comfort levels and improve the ways to manage your pain. Ideally, these programs let the nurses in the hospital ward play a bigger role in keeping track of and managing your pain after surgery, which helps to control your pain more effectively.
Preparing for Postoperative Pain Control
Before having any kind of surgery, a doctor will review your medical history and conduct a physical exam. This helps to understand if there are any conditions or habits that might affect your recovery from the procedure and the kind of pain relief plan that will work for you. The factors that might affect the plan could be the type of procedure you are having, your age, if you have been taking pain killers (opioids) for a long time, or any health conditions (comorbidities) you may have.
Being very overweight can make pain relief with pain killers (opioids) more tricky, because people in this group can be more prone to breathing problems in their sleep (respiratory depression or sleep apnea). So, doctors try to use local pain relief methods (regional anesthetic techniques) and to avoid drugs that can make you drowsy (sedative analgesics). If you are someone who depends on pain killers (opioids) for chronic pain, you will need more than the usual amount during and after the procedure. However, your doctor will try to use a variety of methods (multimodal therapy) including local anesthesia techniques and pain relief medicines that are not opioids.
Looking at the current situation with opioid overuse, doctors also need to take into account if there are any risk factors that might make a patient more likely to misuse opioids. Factors such as being female, being a teenager or older than 50, having depression or a history of misusing drugs, alcohol, antidepressants, or benzodiazepines can all make someone more at risk of continued opioid use after surgery.
How is Postoperative Pain Control performed
Many techniques have been developed and continue to evolve to help manage and reduce pain after surgery. The American Society of Anesthesiologists even released a guideline in 2012, which was approved by the American Society of Regional Anesthesia and Pain Medicine, especially for managing such pain.
Here’s a list of different methods used to manage pain after surgery:
- Medications
- Local treatments and creams
- Special anesthesia techniques
- Therapies that don’t involve medication
When it comes to medications, commonly used examples for post-surgical pain include opioids, anti-inflammatory drugs (NSAIDs), acetaminophen (Tylenol), steroids, gabapentin or pregabalin, ketamine, and lidocaine. Oral administration of opioid medication is preferably over the intravenous (IV) route. In cases where a medication needs to be given through IV (eg, risk of aspiration, ileus), patient-controlled analgesia (PCA) is recommended. PCA is a method of pain control that allows the patient to control the amount of pain medicine they receive. Medications like acetaminophen or NSAIDS can be used in combination with opioids for better pain control and reduced opioid consumption. Gabapentin and pregabalin are recommended pre-surgery, especially for patients with a high tolerance for opioids, as it can reduce the need for opioids post-surgery. Ketamine and lidocaine are also used but are reserved for particular cases due to their potential side effects.
Special techniques for targeted pain control include nerve blocks, injections into joints, infiltration of anesthetics into wounds, and the application of topical anesthetics. The administration of these techniques largely depends on the specific surgical procedure and the expected benefits.
Some surgeries may require anesthetic injections into specific areas or layers of the body, often done by an anesthesiologist using a kind of ultrasound. A continuous IV medication is preferable when postoperative pain is expected to last for a while. Intrapleural analgesia, administration of anesthetics into the pleural space in the chest, isn’t usually recommended as it has its risks and doesn’t provide enough benefits.
Epidural injections, injections into the space around the spinal cord, or injections directly into the spinal canal are used widely in major procedures involving the chest or abdomen, cesarean sections, and surgeries involving the hip or lower body. These are particularly useful in patients with a higher risk of heart or lung-related complications, or in cases where digestion may be severely disrupted or inhibited.
Methods that don’t involve medication are also used to help manage pain. Cognitive modalities like hypnosis, relaxation techniques, and distraction as well as mechanical devices that send small amounts of electrical current through the skin have been used with some success.
To assess how well the pain is being managed, we need to measure the level of pain. This is usually done using a pain scale. The most commonly used scale for such pain is the visual analog scale. Here a line is marked from 0 to 10 with descriptions of pain at both extremes. Zero represents no pain, and ten represents the worst pain one can possibly experience.
Possible Complications of Postoperative Pain Control
If your pain isn’t managed well after an injury or surgery, it can impact your health in many ways. It might make it hard to do your day-to-day tasks, disturb your sleep, make you feel poorly, and lower your interest in sex. On top of this, if your acute or sudden pain is not handled properly, it could turn into chronic or long-term pain.
Taking prescribed painkillers, called opioids, can cause drowsiness, problems with breathing, bladder control issues, feeling sick or throwing up, bowel obstruction, or itching. In severe cases, you can overdose and this could lead to death or long-term health problems. Taking opioids could put you at an increased risk of becoming addicted or developing substance abuse problems. Early signs of withdrawal from opioids can include feeling anxious, unable to rest, tearing up, a runny nose, excessive sweating, problems sleeping, frequent yawning, or muscle aches. Later, you might experience more severe symptoms like diarrhea, cramps in your stomach, having goosebumps, feeling sick or throwing up, a fast heartbeat, high blood pressure, extended pupils, or blurry sight. Another type of medication, Gabapentin or Pregabalin, might cause symptoms such as feeling dizzy or drowsy.
Certain types of pain relief medications, called NSAIDs, can increase the chances of bleeding. This is especially important to keep in mind if you’re at risk of losing more blood, like if you’ve had surgery on a part of your body with many blood vessels, like having your tonsils removed as opposed to having your gallbladder removed. NSAIDs can also slightly raise the risk of getting an ulcer or bleeding in your stomach and problems with your kidneys.
Peripheral regional analgesic techniques, which are ways to numb specific areas of your body, might cause temporary weakness in your muscles, which can increase the risk of falling. When being treated with neuraxial analgesia, a type of deep numbing medication often injected near the spine, you’ll need to be watched closely. This is because it can cause slow breathing, low blood pressure, and muscle weakness from pressure on the spine due to conditions like a blood clot or an infection. If you’re having shoulder surgery, using a continuous intra-articular bupivacaine administration, which involves injecting a local anesthetic into the joint, might raise the risk of a condition called chondrolysis, where the cartilage in the joint breaks down.
What Else Should I Know About Postoperative Pain Control?
Not managing pain well after a surgery can lead to negative health effects and even the development of chronic pain. Understandably, chronic pain can further impact a person’s health and quality of life. Doctors can reduce these risks by understanding how pain works, how to reduce pain, the extent of the surgical procedure, the patient’s pre-existing health conditions, and the patient’s social circumstances. Ensuring appropriate management of pain after surgery has been proven to lessen patient discomfort, shorten hospital stays, help patients move around and go about daily activities sooner, and improve patient satisfaction.
Even though opioid painkillers are important in managing pain after surgery, the rise in injuries and deaths related to opioid overdoses means that doctors should carefully assess a patient’s risk of developing an addiction or misusing the medication before prescribing it. After going home, patients should be told how to store their medication safely and how to dispose of it correctly. It’s crucial to create a personalized plan for managing pain after surgery that emphasizes a combination of methods. Doing this can help to decrease the need for opioids while still effectively relieving pain.