1. Discontinued group (n=33)
Analysis of the risk factor of discontinuation of fentanyl based intravenous patient-controlled analgesia after lumbar spinal fusion surgery
Shigehiko Urabe1, Yoshiaki Terao1, Shozo Tominaga1, Natsuko Oji1, Makito Oji1, Makoto Fukusaki1, Tetsuya Hara2
1Department of Anesthesia, Nagasaki Rosai Hospital, Sasebo, Nagasaki, 2Department of Anesthesiology, Nagasaki University School of Medicine, Nagasaki, Nagasaki Japan.
BACKGROUND
Postoperative period
・Metoclopramide 10mg was injected intravenously when the patients reported PONV and required the antiemetics during postoperative period. The nursing staffs discontinued FIPCA when the patients reported intolerable PONV and required FIPCA discontinuation after metoclopramide administration.
　We compared these parameters between the group of patients continued with FIPCA (C group) and the group of patients discontinued with FIPCA (D group) .
Statistical Analysis
・Intergroup comparisons were performed with Mann-Whitney U test or chi-square test. Multivariate logistic regression analysis for discontinuation of FIPCA were performed. A p value < 0.05 was considered statistically significant.
MATERIALS and METHODS
Table 1 　Background data on each group of patients
Table 3 Multivariate logistic regression analysis
Explanatory variables p
Sex
0.048
Antiemetics use
0.012
Smoking
0.082
Intraoperative fentanyl dosage (㎍/kg)
Fentanyl based intravenous patient-controlled analgesia (FIPCA) is a well-established for postoperative pain control in patients undergoing lumbar spinal fusion surgery. However, fentanyl increases the incidence of postoperative nausea and vomiting (PONV). PONV is a major risk factor of unexpected discontinuation of FIPCA because of intolerable discomfort.
Continued group
Discontinued group p
Number
247 33
Age (years)
67 (60, 85)
76 (62, 82)
0.007
Male / Female (n)
157 / 90
13 / 20
0.008
Height (cm)
160 (153, 168)
155 (149, 160)
0.016
Weight (kg)
60 (51, 70)
52 (48, 66)
0.040
Standard weight (kg)
56 (51, 62)
53 (49, 56)
Body mass index (kg/㎥)
23 (21, 26)
22 (21, 26)
0.330
Smoker / Non smoker (n)
141 / 106
11 / 22
0.010
Intraoperative fentanyl dosage (㎍/kg)
6.7 (4.6,8.6)
5.3 ( 4.6,8.4)
0.442
Postoperative fentanyl administration rate
(㎍/kg/h)
6.7 (4.6, 8.6)
5.3 (4.6, 8.4)
Inhalation anesthesia / Total intravenous anesthesia (n)
21 / 12
0.474
DISCUSSION
PURPOSE
・ Kaufmann et al. found that adding metoclopramide to morphine did not influence the incidence or severity of emesis. However, Silverman et al. studies have found that the addition of droperidol (0.05–0.2 mg / ml) to morphine PCA has reduced the incidence of nausea and vomiting 1).
・ De Oliveira Jr et al. demonstrated that 10 mg i.v. metoclopramide is effective to prevent PONV in patients having surgical procedures under general anaesthesia 2).
・ Apfel et al showed that reduction of PONV was not significantly associated with reduction of morphine equivalents; however, it was associated with a reduction in pain intensity 3).
・ Schaub et al concluded that droperidol at doses of 1mg or less is antiemetic, and that adverse drug reactions are likely to be dose-dependent, there is an argument to stop using doses above 1 mg 4).
The aim of this retrospective study is to identify the risk factors of unexpected discontinuation of FIPCA after lumbar spinal fusion surgery.
MATERIALS and METHODS
Patients
・Total 280 patients administered with FIPCA after lumbar spinal fusion surgery from January to December 2015.
Anesthesia
・The anesthesiologists chose the manners of anesthesia, antiemetics and FIPCA according to clinical requirements. The following information was obtained from the medical chart of each patient:
patient characteristics
types of general anesthesia
the fentanyl dosage used during anesthesia
the concentration of fentanyl in FIPCA
types of antiemetics (metoclopramide 10mg , droperidol mg or no administration) mixed in FIPCA and administrated during anesthesia.
RESULTS
・Table 1
There were significant differences in age, sex, height, weight, standard weight and number of smokers between two groups. There were no significant differences in types of general anesthesia, the dose of fentanyl during anesthesia and the concentration of fentanyl in FIPCA between two groups.
・Table 2
In the FIPCA continued group, patients receiving droperidol were significantly more than those who did not receive antiemetics.This means that droperidol showed a significant antiemetic effect, compared with no administration of antiemetics.
・Table 3
Multivariate logistic regression analysis showed that female gender and no administration of the antiemetics were independent risk factors for unexpected discontinuation of FIPCA.
Our data showed that droperidol may be effective against PONV under FIPCA administration after lumbar spinal fusion Surgery. Our data was consistent with the above argument in some respects.
Table 2 Comparison of types of antiemetics administered during anesthesia between two groups
Continued group (n=247)
Discontinued group (n=33) p
Metoclopramide / droperidol / unused (n)
61 / 121 / 65
8 / 10 / 15
0.052
Metoclopramide / droperidol (n)
61 / 121
8 / 10
0.352
Metoclopramide / unused (n)
61 / 65
8 / 15
0.228
Droperidol / unused (n)
121 / 65
10 / 15
0.015
CONCLUSIONS
This study showed that female gender and no administration of the antiemetics were independent risk factors for unexpected discontinuation of FIPCA.
Low dose of droperidol may be effective against PONV under FIPCA administration after lumbar spinal fusion surgery.
References:
1, Anaesthesia; 52:
2, British Journal of Anaesthsia; 109;
3, PAIN; 154:
4, European Journal of Anaesthesiology; 29: