Postoperative fatigue after day surgery: prevalence and risk factors. A prospective observational study.

BACKGROUND: Postoperative fatigue (POF) is a major cause of rehabilitation failure after surgery. POF is a complication that could negatively affect outpatients but to date no study has specifically investigated POF at home after day surgery. The objective of this study was to assess early and late POF and risk factors for POF after day surgery. METHODS: This prospective single center observational study was conducted from October 2015 to January 2016. All patients scheduled for day surgery under general or regional anesthesia were assessed for eligibility. The primary endpoint was the prevalence of early POF (Day 1), defined by a VAS measurement of fatigue greater than three (on a scale of 0 to 10). Secondary endpoints were the prevalence of late POF (Day 7), the prevalence of severe POF (VAS> 6) at D1 and D7 and risk factors for preoperative fatigue, and for early and late POF. RESULTS: Among 348 patients, the prevalence of early and late POF was 37% (95% CI: 32-42) and 16% (95% CI: 12.1-19.9), respectively. The prevalence of severe POF was 9% at D1 and 3% at D7. The main risk factor for early POF was postoperative pain (P<0.01). CONCLUSIONS: This work suggests that early and late POF are common after day surgery but that severe POF is rare. Postoperative pain is the main risk factors for the early POF. The optimized management of postoperative pain could probably decrease the prevalence of POF after day surgery.

Cardiopulmonary bypass does not induce lung dysfunction after pulmonary thrombarterectomy: role of pulmonary compliance.

OBJECTIVES: Pulmonary endarterectomy is a heavy surgical procedure that is performed under cardiopulmonary bypass (CPB) and aimed to cure postembolic pulmonary hypertension. Reperfusion oedema is both the hallmark of successful surgical procedure and the most frequent postoperative complication. Post-CPB lung dysfunction was not mentioned in any report. We undertook a study to determine whether post-CPB lung dysfunction was present in these patients. METHODS: In a retrospective cohort study with matching on some baseline covariates, we selected 41 patients who had undergone pulmonary endarterectomy and in whom pre-, intra- and postoperative records were complete. The control group was composed of 39 patients operated on from elective cardiac surgery during the same period and matched with a study group for age, gender, body mass index, blood creatinine, diabetes and baseline partial pressure of oxygen/fraction of inspired oxygen ratio. Criteria for post-CPB lung dysfunction were partial pressure of oxygen/fraction of inspired oxygen ratio decrease and bilateral basal oedema. Explanatory variables for post-CPB lung dysfunction were coronary arterial bypass, pleura opening, static pulmonary compliance measured at the time of thorax closed then retracted, fluid infusion, transfusion and vasopressors. RESULTS: All patients operated on from pulmonary endarterectomy presented radiological oedema reperfusion in surgical unblocking areas. Among them, only 2 had bilateral basal oedema when compared to the 24 patients from the control group (P < 0.001). Partial pressure of oxygen/fraction of inspired oxygen ratio increased in the study group and decreased in the control group (30 ± 109 vs -67 ± 134 mmHg, P < 0.001). Control group patients with high-baseline pulmonary compliance were at risk for post-CPB lung dysfunction. CONCLUSIONS: Patients operated on from pulmonary endarterectomy were saved from post-CPB lung dysfunction. The latter could be induced by a mechanical phenomenon.

Early pulmonary compliance increase during cardiac surgery predicted post-operative lung dysfunction.

INTRODUCTION: Lung dysfunction following cardiac surgery is currently viewed as the consequence of atelectasis and lung injury. While the mechanism of atelectasis has been largely detailed, the pathogenesis of lung injury after cardiopulmonary bypass is still unclear. Based upon clinical and experimental studies, we hypothesized that lungs could be injured through a mechanical phenomenon. METHODS: We recorded pulmonary compliance at six key moments of a heart operation in 62 adult patients undergoing elective cardiac surgery. We focused on the period lasting from anesthetic induction to aorta unclamping. We calculated the variation of static and dynamic pulmonary compliance caused by thorax opening; ΔCstat1 and ΔCdyn1 and that caused by cardiopulmonary bypass, ΔCstat2 and ΔCdyn2. Blood gases were performed under standardized ventilation after anesthetic induction and after surgical closure. The PaO2/FiO2 ratio was calculated. ∆PaO2/FiO2 was the criterion for lung dysfunction. We compared ΔCstat1 and ΔCdyn1 with both ∆PaO2/FiO2 and, respectively, ΔCstat2 and ΔCdyn2. RESULTS: Static and dynamic compliance increased with the opening of the thorax and decreased with the start of cardiopulmonary bypass. The PaO2/FiO2 ratio diminished after surgery. ΔCstat1 and ΔCdyn1 were negatively correlated with both ∆PaO2/FiO2 (r=-0.42; p<0.001 and r=-0.44; p<0.001) and, respectively, with ΔCstat2 and ΔCdyn2 (r=-0.59; p<0.001 and r=-0.53; p<0.001). CONCLUSIONS: Increased pulmonary compliance induced by the opening of the thorax is correlated with worsened intrapulmonary shunt after cardiopulmonary bypass. A mechanical phenomenon could be partly responsible for post-operative hypoxemia.