The partial pressure of oxygen decreases as altitude increases, the preoperative chronic hypoxemia (CH) may have a plausible clinical impact. Risk factors for postoperative serious adverse events (pSAEs) in patients living in high altitudes during primary hip arthroplasty (HA) are not clear.This is an observational study embracing patients from January 1, 2011 to December 31, 2015 at Yan’an Hospital of Kunming City, a 1338-bed municipal teaching hospital of Kunming Medical University. Univariate analysis revealed that significant differences between patients with and without preoperative CH occurred in intraoperative hypotension (77 [33%] vs 34 [47%], P = .040) and that significant differences between patients with and without pSAEs occurred in following variables: preoperative CH (32 [57%] vs 199 [80%], P < .001), intraoperative hypotension (37 [66%] vs 74 [30%], P < .001), highest noradrenaline support (.09 [.01–.21] vs .03 [.01–.05] μg/kg/min, P < .001), higher application of general anesthesia (15 [27%] vs 29 [12%], P = .004), and lower of combined-spinal epidural anesthesia (CSEA) (21 [37%] vs 165 [66%], P < .001). The general anesthesia and intraoperative hypotension remained the independent risk factors for pSAEs (P < .05), while the preoperative CH presented by decreasing its risk (P < .05).This study suggests that various intraoperative events including general anesthesia, hypotension were risk factors for the development of pSAEs. Preoperative CH, presenting with decreased incidence of intensive care unit (ICU) admission and pSAEs, may mimic hypoxic preconditioning in organic protection, for which further study is needed to uncover the underlying mechanisms.

Editor-The successful hip arthroplasty (HA) can greatly relieve pain and improve the quality of postoperative life, in patients suffering severe hip diseases including osteoarthritis or fracture. 1 2 However, patient-and surgery-related factors have been linked to a decrease in the quality of life, both perioperatively and later. 3 4 Age, anaesthesia, hypoxaemia, hypotension and anaemia appear to be associated with the development of postoperative outcomes, including delirium in geriatric patients after orthopaedic surgery. 5 6 Surprisingly, few studies have tested the associations between anaesthesia, chronic hypoxaemia, high altitude, patient age, perioperative management and serious adverse events (SAEs) during hip arthroplasty. In view of the above and increasing international recognition that perioperative management demanding a multidisciplinary approach 3 7 does affect patient outcome, we designed a multidisciplinary perioperative management plan for primary hip replacement.Firstly, we retrospectively explored cases of primary HA and then conducted regression analyses to identify outcome risk factors. We found the intraoperative hypotension and general anaesthesia were the independent risk factors for postoperative serious adverse events (SAEs, including ICU admission, malignant arrhythmia, delirium, etc.) with odds ratio (OR) 4.29 and 95% confidence interval (CI) (1.66-11.10), and OR 5.09 with 95% CI (1.96-13.24) respectively. And we conclude that intraoperative hypotension (a mean arterial pressure that was decreased by 30% for more than 3 min) were risk markers of postoperative SAEs in high altitude practice.Secondly, we conducted a multidisciplinary management implementation in patients with moderate to severe hypoxaemia. Then the subsequent patients were shared with shorter postoperative length of stay, of which the median were decreased from 15 days to 11 after implementation (P < 0.001). The perioperative SAE ratios decreased from 21.1% (32/152) initially to 9.4% (18/192) after modification (P ¼ 0.002). The all-cause mortality rate within 30 days decreased by 80% (P ¼ 0.040).A systematic approach optimized to achieve stable haemodynamics with combined-spinal epidural anaesthesia (the most popular method in HA in this hospital) was associated with improved outcome up to 30 days after operation. We must now postulate that a randomized trial is necessary to determine if the multidisciplinary management programme can improve patient outcomes, additional to just measures of hypotension or method of anaesthesia. However, high-quality prospective studies are required to confirm these findings and to establish evidencebased clinical guidelines. Declaration of interestNone declared.

Background: This study aims to explore the clinical efficacy of radiofrequency ozone and injection of anti-inflammatory analgesic solution into the internal orifice of nerve root combined with traditional Chinese medicine hook operation in the treatment of lumbar disc herniation. Methods: The patients with lumbar disc herniation in our hospital from December 20, 2017 to June 19, 2019 were selected as the main research subjects, and the patients were numbered according to the order of their first visits, and the included patients were divided into treatment group and control group using random number table method. Patients in the treatment group were treated with radiofrequency ozone and injection of anti-inflammatory analgesic solution into the internal orifice of nerve root combined with traditional Chinese medicine hook operation. Patients in the control group were treated with traditional lumbar intervertebral disc radiofrequency treatment. The clinical treatment effects of the two groups were observed. Results: A total of 113 patients were included in this study, of which 73 were in the treatment group and 40 were in the control group. The results of the study showed that the NRS scores of patients in the treatment group before treatment were 5±1.68 points, and the NRS scores were 2±0.78 points, 1±0.54 points, and 1±0.77 points 1 month, 3 months, and 1 year after treatment, respectively. The NRS scores of patients in the control group were 3±0.48 points, 2±0.63 points, and 2±0.85 points 1 month, 3 months, and 1 year after treatment. Compared with before treatment and the control group, there were significant differences (P<0.01). Conclusion: Compared with single lumbar intervertebral disc radiofrequency treatment, radiofrequency ozone and injection of anti-inflammatory analgesic solution into the internal orifice of nerve root combined with hook operation can obtain good short-term and medium-term effects in the treatment of lumbar disc herniation. It is a safe and effective minimally invasive treatment method.