Do Intrathecal Opioids Improve Surgical Outcomes After Coronary Artery Bypass Grafting? A Systematic Review and Analysis

BACKGROUND

Intrathecal opioids have long been used as analgesia for intractable cancer pain or as part of spinal anesthesia during obstetric operations. More recently, they have been used preoperatively as a pain management adjuvant for open cardiac and thoracic procedures.

OBJECTIVE

This study aims to analyze the impact of administering intrathecal opioids before cardiac and thoracic surgeries on postoperative pain and mechanical ventilation.

STUDY DESIGN

Systematic review and meta-analysis.

SETTING

University, School of Medicine, and several university-affiliated hospitals.

METHODS

Five outcomes were studied, including the primary outcome of time to extubation, secondary outcomes of analgesia requirements at 24 and 48 hours, resting pain scores at 1 and 24 hours post-extubation, ICU length of stay in hours, and hospital length of stay in days. A search of multiple databases provided 28 studies reporting 4,000 total patients. Outcomes were measured using continuous mean difference with a 95% confidence interval, and the studies were examined for heterogeneity and sensitivity analysis.

RESULTS

The primary outcome analysis suggested that time to extubation was 42 minutes shorter in the intrathecal opioid group (ranging from 82 to 1 minute, P = 0.04). There was also a decrease in postoperative analgesia requirements at both 24 hours (mean difference (MD) = -8.95 mg morphine equivalent doses (MED) [-9.4, -8.5], P < 0.001) and 48 hours (MD = -17.7 mg MED [-23.1, -12.4], P < 0.001) with I2 of 94% and 85% respectively, an improvement of pain scores at both 1 hour (MD = -2.24 [-3.16, -1.32], P < 0.001) and 24-hours (MD = -1.64 [-2.48, -0.80], P =< 0.001) I2 of 94% and 85%, no change in both ICU length of stay (MD = -0.27 hours [-0.55, 0.01], P = 0.06) I2 = 77% and hospital length of stay (MD = -0.30 days [-0.66, 0.06], P = 0.11) I2 = 32%.

LIMITATIONS

The major limitation of this meta-analysis was the inconsistent dosages of intrathecal opioids utilized. Some used the same dose for each patient, while other studies used weight-based doses. The differences in the outcomes observed may then be a result of the different amounts of opioids administered rather than the technique itself. Another limitation was the inconsistent timing of reports for pain scores and postoperative analgesic requirements. Further studies were analyzed at the 2 time periods for both secondary outcomes, making it difficult to attribute the 2 effects solely to the intervention.

CONCLUSIONS

We conclude that preoperative injection of intrathecal opioids is significantly associated with decreased time to extubation, decreased postoperative analgesia requirement, and improved pain scores. In controlled conditions with adequate staff education, this method of analgesia may make it possible to extubate the patients after the surgery in the operating room and fast-track their discharge from the hospital.

Levator muscle resection for simple congenital ptosis: its influence on the preoperative levator function and dose-response ratio

PURPOSE

The primary aim of this study is to calculate the dose-response ratio in patients with different levels of levator function following levator resection in simple congenital ptosis. The secondary outcome is to evaluate the success rate and effect of levator resection on postoperative levator function.

METHODS

In a retrospective study, the medical records of patients were reviewed for age, gender, laterality, preoperative and postoperative measurements (palpebral fissure height, marginal reflex distance 1, and levator function), magnitude of levator resection, follow-up time, and postoperative complications.

RESULTS

Of 154 patients with a mean age of 17.12 ± 11.14 years, 54 patients had excellent levator function, 41 had good function, and 59 had fair function. Following surgery, the mean levator function increased from 8.81 ± 3.40 mm to 11.29 ± 3.25 mm. The magnitude of increase in the 3 groups of excellent, good, and fair was 3.18 ± 2.63, 2.53 ± 2.24 and 1.92 ± 1.80 mm, respectively. The rate of success was 81.8% with no statistically significant difference in the 3 groups. In a multivariate logistic regression, older age, local anaesthesia, and milder ptosis were predictors of success. A table of dose-response ratios was calculated that determined the amounts of levator muscle resection for 1 mm of marginal reflex distance 1 and levator function increase.

CONCLUSIONS

Levator resection has high success rate in patients with simple congenital ptosis. The function of levator muscle improved significantly following surgery, and the rate of improvement was higher in patients with better preoperative levator function.

Measurement of mitral valve area by direct three dimensional planimetry compared to multiplanar reconstruction in patients with rheumatic mitral stenosis

Mitral valve area (MVA) measurement by three-dimensional transesophageal echocardiography (3D-TEE) has a crucial role in the evaluation of mitral stenosis (MS) severity. Three-dimensional direct (3D-direct) planimetry has been proposed as a new technique to measure mitral valve area. This study aimed to compare the 3D-direct mitral valve planimetry to conventional three-dimensional multiplanar reconstruction (3D-MPR) in severe MS using 3D-TEE. In this cross-sectional, prospective study; 149 patients with severe MS who were referred for transesophageal echocardiography in Shahid Madani Hospital (Tabriz Iran), just before percutaneous transmitral commissurotomy (PTMC), recruited consecutively. All patients underwent 2D transthoracic echocardiography (2D-TTE) and 3D-TEE in a single session before PTMC. During 2D-TTE planimetry, pressure half time (PHT), and proximal isovelocity surface area (PISA) were applied to measure the MVA. Transmitral mean pressure gradient (MPG) was measured. During 3D-TEE, MVA planimetry was carried out with both 3D-direct and 3D-MPR methods. 3D-direct was applied from both atrial and ventricular views. The consistency of MVA measurements with 3D-direct, 3D-MPR, and 2D-TTE methods was statistically investigated. Our sample consisted of 109 (73.2%) women and 40 (26.8%) men. The mean age was 51.75 ± 9.81 years. The agreement between 3D-direct and 3D-MPR planimetry was significant and moderate (0.99 ± 0.29 cm2 vs. 1.12 ± 0.26 cm2, intraclass correlation = 0.716, p value = 0.001).The accuracy of the 3D-direct method reduced significantly compared to the MPR method at MVA > 1.5 cm2. The maximum difference between two methods was observed in cases with MVAs larger than 1.5 cm2. MVA measured with the 3D-MPR method was significantly correlated with a 2D-TTE method, with a moderate agreement (intraclass correlation = 0.644, p value = 0.001). Also, 2D-TTE and 3D-direct TEE techniques yielded significantly consistent measurements of the MVA (1.06 ± 0.026 cm2 vs. 0.99 ± 0.29 cm2, intraclass correlation = 0.787, p value = 0.001); however, with a slight overestimation of the MVA by the former with a net difference of 0.06 ± 0.013 cm2. Mitral valve pressure gradient (MPG) had no significant correlation with planimetry results. A significant inverse correlation was seen between the MVA and pulmonary arterial systolic pressure. 3D-direct planimetry has an acceptable agreement with 3D-MPR planimetry at MVA less than 1.5 cm2, but their correlation decreases significantly at MVA above 1.5 cm2. 3D-direct planimetry underestimates MVA compared to 3D-MPR, especially at MVA above 1.5 cm2. It seems that the saddle shape of mitral valve, interferes with 3D-direct measurement of commissures at moderate MS. The 2D-TTE planimetry has generally acceptable accuracy, but its correlation to the 3D-TEE methods is significantly reduced in cases with moderate to severe MS (i.e. MVA > 1.0 cm2).

Can 5-minute Apgar score be considered as an additional independent risk factor for screening of retinopathy of prematurity?

Introduction: Because of increasing the population of premature infants due to improving neonatal care we try to find other independent criteria in addition to birth weight and gestational age to reduce the number of infants who need a retinopathy of prematurity (ROP) screening examination. Methods: This is a retrospective cross-sectional study, included 150 preterm infants with gestational age of ≤ 32 weeks or birth weight ≤ 1500 g or receives oxygen therapy for more than 2 days, who were examined from the fourth week of life for ROP in Tabriz Al-Zahra hospital’s neonatal intensive care unit (NICU), from March 2017 to January 2018. All infants with other risk factors such as multi gestational pregnancy, blood transfusion or exchange, phototherapy, underlying disease, cerebral hemorrhage, chronic lung disease and sepsis were excluded from the study. Infants divided to two group ROP (n=47) and non-ROP (n=133) and their 5-minute Apgar score was Apgar score was compared as an independent risk factor. Exploratory data analysis was performed using descriptive measures with independent samples t tests. Kolmogorov-Smirnov tests were used to test the normality of data distribution. Results: The mean 5-minute Apgar scores were statistically lower in ROP group (5.4±2.3) than non-ROP group 6.2±2.1 (P value=0.041). Conclusion: Apgar score was statistically significant, but in light of the very close results obtained, it seems prudent to consider an independent risk factor.

Seasonal variations and the risk of venous thromboembolism: A narrative review article

Different investigations on seasonal variations of the pulmonary thromboembolism and deep vein thrombosis (DVT) incidence have not yielded a definite conclusion. Some papers showed significant increase in incidence of thromboembolism in winter; on the other hand, others neglected that correlation. Some articles have tried to show infrastructure of these variations. Better understanding of the cornerstone of these variations can result in prevention of disease and saving lives of susceptible people. In this narrative review article, we reviewed previous articles according to the region of study and tried to find the factors affecting diverse results among different studies.