Semi-skeletonized internal mammary grafts and phrenic nerve injury: Cause-and-effect analysis

Abstract

Phrenic nerve injury after cardiac surgery increases postoperative pulmonary complications. The purpose of this study was to analyze the causes and effects of phrenic nerve injury after cardiac surgery. Prospectively collected data on 2084 consecutive patients who underwent cardiac surgery from Jan. 1995 to Feb. 2002 were analyzed. Twenty-eight preoperative and operation related variables were subjected to logistic analysis with the end point being phrenic nerve injury. Then phrenic nerve injury and 6 perioperative morbidities were included in the analysis as variables to determine their independent predictive value for perioperative pulmonary morbidity. An identical approach was used to identify the independent risk factors for perioperative mortality. There were 53 phrenic nerve injuries (2.5%). There was no phrenic nerve injury in non-coronary surgery or coronary surgery using conduits other than the internal mammary artery. The independent risk factors for phrenic nerve injury were the use of internal mammary artery (Odds ratio (OR) = 14.5) and thepresence of chronic obstructive pulmonary disease (OR = 2.9). Phrenic nerve injury was an independent risk factor (OR = 8.1) for perioperative pulmonary morbidities but not for perioperative mortality. Use of semi-skeletonized internal mammary artery harvesting technique and drawing attention to possible vascular or mechanical causes of phrenic nerve injury may reduce its occurrence. Unilateral phrenic nerve injury, although rarely life-threatening, is an independent risk factor for postoperative respiratory complications. When harvesting internal mammary arteries, it should be kept in mind avoiding stretching, compromising, or inadvertently dissecting phrenic nerve is as important as avoiding damage of internal mammary artery itself.

Diaphragmatic palsy after cardiac surgery in adult and pediatric patients

“…2 The reported incidence in adults is 1.2% to 60%. 1,5,6 In our study, the incidence of DP was 0.98% in pediatric patients, with the highest incidence after a bidirectional Glenn shunt, and 0.43% in adults. Important anatomic relationships between the phrenic nerves and structures in the thorax play a major role in injury of this nerve during cardiac surgery.…”

Design and analysis of cryogenic CO2 separation from a CO2‐rich mixture

“…The grey relational analysis is a type of grey system analysis method that measures the degree of correlation between factors according to the degree of similarity or difference in the development trend between factors 41 . Here, we used the grey relational analysis method to analyze the correlation between the influencing factors and key parameters.…”

Prediction of Soil Creep Deformation Using Unequal Interval Multivariable Grey Model

“…The conventional grey model which was established based on the equal interval original data was difficult to predict the deformation reasonably when the measured data were taken from unequal interval time. Therefore, this grey model was improved to the conventional grey model [2,3]. And then the remaining prestress of the horizontal anti-slide slab or the abutment can be calculated by multiplying their stiffness with displacement.…”