Prevalence of pain 6 months after surgery: a prospective observational study.

BACKGROUND: Pain after surgery is a major issue for patient discomfort and often associated with delayed recovery. The aim of the present study was to evaluate the prevalence of pain and requirement for analgesics up to 6 months after elective surgery, independent if new pain symptoms occurred after surgery or if preoperative pain persisted in the postoperative period. METHODS: A prospective observational single center cohort study was conducted between January 2012 and August 2013. Eligible patients were scheduled to undergo elective surgical interventions including joint (hip, knee arthroplasty), back (nucleotomy, spondylodesis), or urological surgery (cystectomy, prostatectomy, nephrectomy). Pain was assessed on an 11-point numerical rating scale (NRS) before, on postoperative day 2 and 6 months after surgery. Clinical information was collected with structured questionnaires and by telephone interview. RESULTS: Six hundred and forty-four patients gave informed consent, including 54.4 % men (mean age 62.2, SD 14.3). Higher preoperative pain scores were found in patients undergoing joint (mean 7.6; 95 % confidence interval [CI]: 7.2-8.0) and back surgery (mean 7.1, CI: 6.8-7.5) than in patients prior to urological surgery (mean 2.3; CI: 1.8-2.8). After 6 months, about 50 % of patients after joint or back surgery indicated pain levels ≥3/10, compared to 15.9 % of patients after urological surgery (p < .001). 35.3 % of the patients after joint surgery and 41.3 % after back surgery still use pain medication 6 months postoperatively, in contrast to 7.3 % of patients after urological surgery. 13.6 % of patients who underwent back surgery indicated the regular intake of opioids. CONCLUSIONS: Our results reveal that a significant percentage of patients undergoing procedures in joint or back surgery still need pain medication up to 6 months postoperatively due to ongoing pain symptoms. Improved monitoring of pain management is warranted, especially after discharge from hospital, to improve long-term results. TRIAL REGISTRATION: Clinicaltrials.gov (Identifier: NCT01488617 ); date of registration December 6th 2011.

Comparison of the gold standard of hemoglobin measurement with the clinical standard (BGA) and noninvasive hemoglobin measurement (SpHb) in small children: a prospective diagnostic observational study.

INTRODUCTION: Collecting a blood sample is usually necessary to measure hemoglobin levels in children. Especially in small children, noninvasively measuring the hemoglobin level could be extraordinarily helpful, but its precision and accuracy in the clinical environment remain unclear. In this study, noninvasive hemoglobin measurement and blood gas analysis were compared to hemoglobin measurement in a clinical laboratory. METHODS: In 60 healthy preoperative children (0.2-7.6 years old), hemoglobin was measured using a noninvasive method (SpHb; Radical-7 Pulse Co-Oximeter), a blood gas analyzer (clinical standard, BGAHb; ABL 800 Flex), and a laboratory hematology analyzer (reference method, labHb; Siemens Advia). Agreement between the results was assessed by Bland-Altman analysis and by determining the percentage of outliers. RESULTS: Sixty SpHb measurements, 60 labHb measurements, and 59 BGAHb measurements were evaluated. In 38% of the children, the location of the SpHb sensor had to be changed more than twice for the signal quality to be sufficient. The bias/limits of agreement between SpHb and labHb were -0.65/-3.4 to 2.1 g·dl(-1) . Forty-four percent of the SpHb values differed from the reference value by more than 1 g·dl(-1) . Age, difficulty of measurement, and the perfusion index (PI) had no influence on the accuracy of SpHb. The bias/limits of agreement between BGAHb and labHb were 1.14/-1.6 to 3.9 g·dl(-1) . Furthermore, 66% of the BGAHb values differed from the reference values by more than 1 g·dl(-1) . The absolute mean difference between SpHb and labHb (1.1 g·dl(-1) ) was smaller than the absolute mean difference between BGAHb and labHb (1.5 g·dl(-1) /P = 0.024). CONCLUSION: Noninvasive measurement of hemoglobin agrees more with the reference method than the measurement of hemoglobin using a blood gas analyzer. However, both methods can show clinically relevant differences from the reference method (ClinicalTrials.gov: NCT01693016).