Clinical characteristics and analysis of risk factors for heart injuries in 55 patients with lightning injury on plateau in Tibet Autonomous Region

Abstract

Objective: To explore the clinical characteristics and treatment outcomes of patients with lightning injury on plateau in Tibet Autonomous Region, and to analyze the risk factors for heart injuries in these patients. Methods: A retrospective case series study was conducted. From January 2008 to July 2023, 55 patients with lightning injury who met the inclusion criteria were admitted to the General Hospital of PLA Tibet Military Area Command. The gender, age, ethnicity, time of injury, location of injury (average altitude), activity at the time of injury, the occurrence of thermal burns on the body surface, the occurrence of complication, the occurrence of combined injury, underlying disease or physiological process before injury, length of hospital stay, treatment outcome, and effective rate of treatment were recorded. The patients were divided into juvenile group (11 cases), young group (28 cases), middle-aged group (14 cases), and elderly group (2 cases) according to age bracket, then the gender and ethnicity distribution of patients in the 4 groups were compared. According to the occurrence of heart injuries at admission, the patients were divided into heart injury group (44 cases) and non-heart injury group (11 cases), then the gender, age, ethnicity, average altitude of location of injury, length of hospital stay, the occurrence of complication, the occurrence of combined injury, site of thermal burns on the body surface, and area of thermal burns on the body surface in patients were compared between the two groups. Data were statistically analyzed with Mann-Whitney U test, chi-square test, or Fisher's exact probability test. The multivariate logistic regression analysis was conducted to screen the independent risk factors for heart injury in patients with lightning injury. Results: Among the 55 patients aged 10-68 years, 39 were male and 16 were female, including 47 Tibetans and 8 Hans. There were no statistically significant differences in gender or ethnicity distribution of patients among the 4 groups with different age brackets (P>0.05). Lightning injuries occurred from May to September, which mostly occurred in June and July. The incidence of lightning injury was higher in Chengguan District of Lhasa City (average altitude of 3 650 m) and Baqing County of Naqu City (average altitude of 4 500 m), being 20.0% (11/55) and 16.4% (9/55), respectively. A total of 96.4% (53/55) of the patients were engaged in outdoor activities when injured, such as grazing, digging Cordyceps, and harvesting highland barley. Among the 55 patients, 46 (83.6%) cases had thermal burns on the body surface, with burn area mainly being not more than 10% total body surface area and burn depth mainly being deep partial-thickness. Fifty-two (94.5%) patients had complications, with heart injury being the most common complication (44 cases, 80.0%). Twenty-two (40.0%) patients had 11 combined injuries, and traumatic brain injury was the most common combined injury. Seventeen (30.9%) patients had 11 underlying diseases or physiological processes before injury. The length of hospital stay of patients was 9 (5, 17) d. Among the 55 patients, 14 cases were cured and discharged, 40 cases were improved, and 1 case died, with effective rate of treatment of 98.2%. Compared with those in non-heart injury group, the proportion of complication occurrence (χ2=12.28), the proportion of trunk burns (χ2=5.15), and the average altitude of location of injury (Z=-2.38) of patients in heart injury group were increased significantly (P<0.05), while there were no significant changes in the other indicators (P>0.05). Multivariate logistic regression analysis showed that the average altitude at the location of injury was the independent risk factor for heart injury in patients with lightning injury (with odds ratio of 3.28, 95% confidence interval of 1.35-7.99, P<0.05). Conclusions: Lightning injuries on plateau in Tibet Autonomous Region mainly occur from May to September, with an average altitude of 4 500 m at the location of injury. Patients with lightning injury are injured when participating outdoor activities, and the affected patients are mainly mainly young male Tibetans. Most of the injuries are mild burns. Lightning injuries are complex and have many complications, with heart injury being the most common one. The average altitude at the location of injury is the independent risk factor for heart injury in patients with lightning injury.