• 
• 

Three Part Question

In[a patient with sickle cell disease presenting with a painful crisis] is [a PCA better than intermittent pain relief] in [the management of pain]?

Clinical Scenario

A 24 year old woman presents to the emergency department with sickle cell painful crisis. The pain is in both arms and legs and is consistent with her normal crisis. As you promptly administer intermittent pain relief medication, you wonder to yourself would a PCA be more effective method of pain relief.

Search Strategy

MEDLINE (1966 to present)
EMBASE (1988 to present)
Cochrane library
OVID: [sickl$.mp.] AND [exp Anemia/ or anaemia$.mp] OR [exp Anemia, Sickle Cell/ or sickle cell crisis.mp.] AND [painful.mp. and crisis.mp.] AND [exp Analgesia, Patient-Controlled/PCA]

Search Outcome

This search yielded 12 articles. Bibliographic references found in these articles were also examined to identify related literature. Only original research articles were included. Two articles directly addressed the question.
Other mesh terms were also searched such as "intermittent", "morphine" and "drug administration" however yielded no further results. The Cochrane library was also searched but no further relevant papers were obtained.

Relevant Paper(s)

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study Weaknesses
Gonzalez, ER 1991 USA	59 patients in a two part study	Randomized trial	Assessment of morphine sulfate administration by intermittent intravenous (IV) injections against patient-controlled analgesia(PCA) in patients in the emergency department with sickle cell crisis pain.	Morphine administered by PCA is as effective as an aggressive fixed-schedule Int-IV morphine regimen for the treatment of vaso-occulsive sickle cell crisis pain in the Emergency Department.First phase (WMD –0.10 mm, 95% CI –27.03 mm to +26.83 mm) and the second phase (WMD +9.00 mm, 95% CI –18.25 mm to +36.25 mm). It found no significantdifference in the total amount of morphine administered between patient controlledanalgesia and intermittent intravenous analgesia in the first phase (WMD –6.70 mg,95% CI –23.35 mg to +9.95 mg) or the second phase of the study (WMD +6.40 mg,95% CI –8.71 mg to +12.51 mg).	Small size Hard to standardize the reports of pain as it is subjective. No mention of how the patients were randomly allocated.
Perlin, E 1993 USA	20 adults aged 17-39 years	Randomized controlled trial	Pain relief	It found no significant difference between patient controlled and intermittent analgesia. There was no difference in the amount of meperidine used each day. Measured by categorical and analogue pain scales (categoricalscores on day 2: WMD +4.0 mm, 95% CI –1.09 mm to +9.09 mm; analogue scores:WMD +68.00 mm, 95% CI –25.35 mm to +161.35 mm). It also found no significantdifference in the amount of meperidine used each day after 3 days (WMD +451 mg,95% CI –70 mg to +972 mg).	Small study size. The units being measured in the pain scales were not defined

Comment(s)

From these two randomized controlled trials no significant difference in pain between patient controlled analgesia and the intermittent parenteral treatment was found. The incidence of side effects was also similar in both regimens. Another study found that initiating a PCA in the emergency department instead of on the ward was preferred by most patients. One study also found that high dose PCA/low basal infusion (HPCA/LBI) compared to low dose PCA/high basal infusion (LPCA/HBI) causes fewer hospitalized days, lower pain scores and a decreased consumption of morphine in children with sickle cell crisis[2] It has been found that patient preference strongly favours PCA over other methods of analgesia as it provides better pain relief without any increase in side-effects.[3] However in the trials review one major flaw in the Gonzalez study was that of the tight fixed schedule of nurse titrated analgesia which was abnormally systematic (according to a retrospective evaluation of drug usage before the study) and may thus be under-estimating PCA's potential.

Clinical Bottom Line

There is no significant difference in pain relief between PCA against intermittent parenteral morphine. Depending on patients' preference, I would recommend the use of the PCA in patients with sickle cell crisis.

References

1. Melzer-Lange MD et al . Patient-controlled analgesia for sickle cell pain crisis in a pediatric emergency department Pediatric Emergergency Care 2004;2-4
2. NO Trentadue, MK Kachoyeanos, G Lea A comparison of two regimens of patient-controlled analgesia for children with sickle cell disease Journal of Pediatric Nursing 1998;15-19
3. Ballantyne JC Postoperative patient-controlled analgesia:meta-analyses of initial randomized controlled trials Journal of Clincal Anesthesia 1993;182-193
4. Gonzalez ER et al Intermittent Injection vs patient-controlled analgesia for sickle cell crisis pain. Comparison in patients in the emergency department. Archives of internal medicine. Vol. 151 (1991) 1373-1378
5. Perlin E et al . Infusional/patient-controlled analgesia in sickle cell vaso-occulsive crises Pain Clinic 1993;36:113-119