Chronic postsurgical pain in children: prevalence and risk factors. A prospective observational study.

BACKGROUND: Chronic postsurgical pain (CPSP) is well known in adults, with prevalence rates ranging from 10 to 50%. Little is known about the epidemiology of CPSP in children. The aim of this prospective observational study was to evaluate the prevalence of CPSP after surgery in children. METHODS: After informed consent, children aged six to18 yr were included. Characteristics and risk factors for CPSP were recorded. Exclusion criteria included ambulatory surgery, refusal, inability to understand and change of address. All eligible children completed a preoperative questionnaire the day before surgery about pain, anxiety and their medical history. All data concerning anaesthetic and surgical procedures, such as acute pain scores (VAS) during the first 24 h were recorded. Three months after surgery all included children were sent a postoperative questionnaire about pain at the surgical site. RESULTS: Altogether, 291 children were enrolled; the mean age was 12 yr, most subjects were male (60%). The most common type of surgery was orthopaedic (63%). In the 258 patients who completed the study, the prevalence of CPSP was 10.9%, most often with a neuropathic origin (64.3%). The two main risk factors were the existence of recent pain before surgery (<1 month) and the severity of acute postoperative pain (VAS >30 mm) in the first 24 h after orthopaedic and thoracic surgeries. Six months after surgery, only five children needed a visit with a chronic pain practitioner. CONCLUSIONS: These results highlight the necessity of evaluating and treating perioperative pain in order to prevent CPSP in children.

Reducing tidal volume and increasing positive end-expiratory pressure with constant plateau pressure during one-lung ventilation: effect on oxygenation.

BACKGROUND: It is no longer safe to use large tidal volumes (V(T)) (>8 ml kg(-1)) for one-lung ventilation (OLV), and limiting plateau pressure should be a major objective. Due to the specificity of OLV, the use of positive end-expiratory pressure (PEEP) remains controversial. This study determined whether at the same low plateau pressure, reducing V(T) and increasing PEEP were not inferior to larger V(T) and lower PEEP ventilation in terms of oxygenation. METHODS: This prospective, randomized, non-inferiority, cross-over trial included 88 patients undergoing open thoracotomy who received two successive ventilatory strategies in random order: V(T) (8 ml kg(-1) of ideal body weight) with low PEEP (5 cm H(2)O), or low V(T) (5 ml kg(-1)) with a high PEEP. Respiratory rate and PEEP were, respectively, adjusted to maintain constant ventilation and plateau pressure. The primary endpoint was the ratio under each ventilatory strategy. RESULTS: The non-inferiority of low-V(T) ventilation could not be established. The mean adjusted ratio was lower overall during low-V(T) ventilation, and differences between the two ventilatory modes varied significantly according to baseline (T0). Decreased oxygenation during low V(T) was smaller when baseline values were low. Systolic arterial pressure was not lower during low-V(T) ventilation. CONCLUSION: During OLV, lowering V(T) and increasing PEEP, with the same low plateau pressure, reduced oxygenation compared with larger V(T) and lower PEEP. This strategy may reduce the risk of lung injury, but needs to be investigated further.

[Unexpected respiratory complication after the surgical treatment of scoliosis in a teenager]. / Complication respiratoire inattendue après le traitement chirurgical d'une scoliose chez un adolescent.

We report the case of an unexpected respiratory complication after a surgical treatment of scoliosis during postoperative period in an adolescent patient. This complication results of a vascular compression of the left main bronchus between the aorta and the pulmonary artery, which induces severe atelectasis of left lower lobe. Prolonged non-invasive ventilation with high level of positive end-expiratory pressure prevents aorto-pulmonary compression, allows a pulmonary recruitment associated with a favorable prognostic for the adolescent.

Pressure-controlled ventilation and intrabronchial pressure during one-lung ventilation.

BACKGROUND: Pressure-controlled ventilation (PCV) has been suggested to reduce peak airway pressure (P(peak)) and intrapulmonary shunt during one-lung ventilation (OLV) when compared with volume-controlled ventilation (VCV). At the same tidal volume (V(T)), the apparent difference in P(peak) is mainly related to the presence of a double-lumen tracheal tube. We tested the hypothesis that the decrease in P(peak) observed in the breathing circuit is not necessarily associated with a decrease in the bronchus of the dependent lung. METHODS: This observational study included 15 consecutive subjects who were ventilated with VCV followed by PCV at constant V(T). Airway pressure was measured simultaneously in the breathing circuit and main bronchus of the dependent lung after 20 min of ventilation. RESULTS: PCV induced a significant decrease in P(peak) [mean (sd)] measured in the breathing circuit [36 (4) to 26 (3) cm H(2)0, P<0.0001] and in the bronchus [23 (4) to 22 (3) cm H(2)O, P=0.01]. However, the interaction (ventilatory mode x site of measurement) revealed that the decrease in P(peak) was significantly higher in the circuit (P<0.0001). Although the mean percentage decrease in P(peak) was significant at both sites, the decrease was significantly lower in the bronchus [5 (6)% vs 29 (3)%, P<0.0001]. CONCLUSIONS: During PCV for OLV, the decrease in P(peak) is observed mainly in the respiratory circuit and is probably not clinically relevant in the bronchus of the dependent lung. This challenges the common clinical perception that PCV offers an advantage over VCV during OLV by reducing bronchial P(peak).