The Future of Patient-Controlled Analgesia in Clinical Spaces

Patient-controlled analgesia (PCA) is the administration of pain controlling substances such as opioids or narcotics, where the patient has some ability to adjust their own level of medication. By 1973, an average of 50% of postoperative patients reported unsatisfactory pain relief.¹ The inefficacy of the current delivery methods, coupled with the realization that small opioid doses based on the patient’s wishes were more effective than larger doses given independently of the patient’s wishes, led to the creation of PCA.¹ It is usually delivered via an infusion pump, which allows for varying doses and delivery rates for more customized treatment plans. PCA is also versatile, allowing administration to children and elderly patients as well as allowing for delivery via different routes: intranasal, spinal, sublingual, and regional.² Opioids, dosages, lockout intervals (period whereby patients may not re-administer pain medication), and delivery rates are all customizable parameters.¹ However, it is crucial that cost-benefit analyses are conducted to further test the safety and efficacy of this delivery system. 

Although there is a need for further research, there have been several studies that have highlighted the benefits and limitations of patient-controlled analgesia. A study testing the effectiveness of sublingual sufentanil tablet system (PCA) vs nurse-controlled morphine (control) for inducing analgesic in postoperative cardiac surgery patients found adequate pain relief and lower opioid consumption in the PCA group, results that have been supported in other research^.3 Another study found that patient-controlled analgesia actually provided better pain relief after cardiac surgery. ⁵ In addition, studies found that PCA increases patient satisfaction with the post-operative process.⁴  

However, it is important to note that PCA does have limitations. A randomized controlled trial found that patients who had received thoracic epidural analgesics (control) after major hepato-pancreato-biliary surgery had lower pain scores and less opioid use than the patients who received IV-PCA.⁶ There have also been several side effects associated with PCA such as nausea, vomiting, itchy skin, and confusion.¹ A meta-analysis found that PCA can lead to the over-administration of opioids postoperatively or injury, which can ultimately hide complications.⁴ Patients also report fear of overdose and addiction when they are able to control the delivery of their pain medication.⁴ Furthermore, patients suffering from renal impairment, morbid obesity, and obstructive sleep apnea have increased risk of respiratory depression and therefore require more careful monitoring by nurses.⁴  

As patient-controlled analgesia becomes more prevalent, it is critical that a thorough set of double-blind and randomized controlled trials are conducted to further elucidate the safety and effectiveness of this relatively novel method. Errors in this delivery method can be addressed through use of superior programming and improved training to assemblers, anesthesiologists, nurses and patients, along with fail safes to ensure the safety of the user. PCA has promising potential for revolutionizing the future of pain management in medical spaces. 

References 

1. Grass, J. A. Patient-Controlled Analgesia. Anesthesia & Analgesia 101, S44 (2005). DOI:10.1213/01.ane.0000177102.11682.20 

2. Lehmann, K. A. Recent Developments in Patient-Controlled Analgesia. Journal of Pain and Symptom Management 29, 72–89 (2005). 

3. Tittelboom, V. V. et al. Sublingual Sufentanil Tablet System Versus Continuous Morphine Infusion for Postoperative Analgesia in Cardiac Surgery Patients – Journal of Cardiothoracic and Vascular Anesthesia. (2020). https://www.jcvaonline.com/article/S1053-0770(20)30824-7/fulltext 

4. Macintyre, P. E. Safety and efficacy of patient-controlled analgesia. British Journal of Anaesthesia 87, 36–46 (2001). DOI:10.1093/bja/87.1.36 

5. Nemati, M. The evaluation of the benefits of pain control by patients using PCA pump compared to medicine injection to ease the pain by nurses. J Med Life 8, 144–149 (2015). 

6. Aloia, T., Kim, B., Segraves-Chun, Y. S. & Cata, J. A Randomized Controlled Trial of Postoperative Thoracic Epidural Analgesia Versus Intravenous Patient Controlled Analgesia after Major Hepatopancreatobiliary Surgery. (2018). https://www-ncbi-nlm-nih-gov.ccl.idm.oclc.org/pmc/articles/PMC5784834/