Trauma in the elderly is associated with poorer results than trauma in the younger population, with age and the occurrence of comorbidities being more predictive of morbidity and mortality than the severity of injuries (7).
This was a comparative cross-sectional study that included elderly trauma patients presenting with traumatic hypovolemic shock admitted to the Emergency Department of Suez Canal University Hospital. This study was designed to compare controlled hypotension and usual resuscitation regimens regarding outcomes.
In this study, the study participants were managed into two ways. The first group received fluid resuscitation with the target systolic blood pressure being 90 mmHg (n = 37) and the second group received fluid resuscitation with the target systolic blood pressure being 100 mmHg (n = 37). The mean age of the sample under study was 69.45 ± 3.1 years. Approximately half of the patients were manual workers, and approximately 28 were employers. Additionally, no statistically significant difference in the history of chronic illness was found between the two groups.
In this study, the most common mechanism of trauma in both groups was motor car accident (51.3% in the controlled hypotension group and 54.1% in the 2nd group). Meanwhile, the most common type of trauma was blunt trauma (75.7% in the controlled hypotension group and 86.5% in the 2nd group). No statistically significant difference in the mechanism of trauma (p = 0.93) or the type of trauma (p = 0.48) was observed between the controlled hypotension and 2nd groups.
Alternatively, several studies have reported that the most common mechanism of trauma in elderly was falls. Gowing et al (19) have reported that the mechanisms of injury included falls (64%), motor vehicle collision (27%), injury from machinery (3%), injury from natural and environmental causes (2%), suicide or self-inflicted injury (3%), and burns (1%).
Another study on severe trauma in geriatric patients has reported that falls are the most common cause of trauma and the leading cause of trauma-related deaths in this population (7).
This contradiction may be explained by the difference in the study population, inclusion criteria, and site of the study. As this study was conducted in Suez Canal University Hospital, which is a tertiary care facility, it receives more cases of motor car accidents than usual.
In this study, no statistically significant difference in baseline systolic and diastolic blood pressure measures was observed between both groups. However, patients in the controlled hypotension group had a significantly lower mean systolic blood pressure after receiving fluids than those in the 2nd group (p < 0.001).
These results are due to the effects of controlled hypotension that results from balanced resuscitation and this is why controlled hypotension is not recommended in case of head trauma.
Almost all studies discussing the effects of damage control resuscitation have reported that controlled hypotension results in lower blood pressure readings as it aims to keep the systolic blood pressure Between 80–90 mmHg (20, 21).
Moreover, no statistically significant differences in base deficit and coagulopathy at baseline and after resuscitation were observed between the controlled hypotension and 2nd groups. However, after resuscitation, patients in the controlled hypotension group had significantly less severe base deficit than those in the 2nd group (p = 0.04).
A large randomized, double-blind, parallel-group trial showed the mean improvement in base deficit excess during the first 24h with Plasma-Lyte A than with 0.9% sodium chloride (7.5 ± 4.7 vs. 4.4 ± 3.9 mmol/L; difference: 3.1 (95% confidence interval (CI): 0.5–5.6)). At 24 h, arterial pH was greater (7.41 ± 0.06 vs. 7.37 ± 0.07; difference: 0.05 (95% CI: 0.01–0.09)) and serum chloride was lower (104 ± 4 mEq/L vs. 111 ± 8 mEq/L; difference: −7 (95% CI: −10 to − 3)) with Plasma-Lyte A than with 0.9% sodium chloride (22).
In contrast, a meta-analysis discussing the use of ringer lactate versus isotonic saline in critically ill patients has reported that ringer lactate and isotonic saline have no difference in various clinical outcomes, including in-hospital mortality, and overall ICU mortality (23).
Meanwhile, regarding coagulopathy, patients in the controlled hypotension group had significantly lower INR levels (< 1.5) than the 2nd group (p < 0.001). Similarly, a randomized control trial has reported that implementing a controlled hypotension strategy in patients may reduce the risk of early postoperative mortality from coagulopathic bleeding (24).
Trauma increase the risk of coagulopathy due to acquired quantitative and qualitative platelet defects, hypocoagulable states, and dysregulation of the fibrinolytic system a phenomenon referred to as fibrinolytic shutdown (25). Thus, the ability to reduce INR, along with the coagulopathy risk, is a great advantage of controlled hypotension as it decreases the need for crystalloid infusion.
In this study, intraperitoneal free fluid collection was found in 70.3% of the patients in the controlled hypotension group and approximately 84% of the patients in the 2nd group (p = 0.17). Other findings included splenic injury, hemothorax, and pericardial effusion (only one case in each group). Similarly, a study has reported that excessive fluid resuscitation causes abdominal compartment syndrome among critically ill or injured patients, such as abdominal trauma, pelvic fracture, and intra-abdominal organ injuries (26).
Additionally, in this study, both study groups had the same type of crystalloid fluid resuscitation, but regarding the amount of fluids administered, the 2nd group had a statistically significant higher amount (total amount of crystalloid, Ringer’s lactate, and normal saline) to be able to maintain systolic blood pressure at 100mmHg than the controlled hypotension group. In contrast, patients in the controlled hypotension group received significantly more colloid fluids than those in the 2nd group (p < 0.001). Additionally, the controlled hypotension group had a significantly higher amount of all types of colloid fluids (i.e., plasma, platelets, and packed RBC) than the 2nd group.
Furthermore, the controlled hypotension group has less incidence of death at the emergency room (21.6%) than the 2nd group (35.1%) (p = 0.04). Damage controlled resuscitation and controlled hypotension as one of its 3 component decreases the odds of mortality among patients in the emergency room by 10.9% compared with usual resuscitation (p < 0.001). Similarly, a multicenter randomized controlled trial, known as the Colloids Versus Crystalloids for the Resuscitation of the Critically Ill trial, has compared the mortality rate of critically ill patients who received colloids (n = 1414; gelatins, dextrans, hydroxyethyl starches, or 4% or 20% albumin) with that of patients who received crystalloids (n = 1443; isotonic or hypertonic saline or Ringer’s lactate) for fluid resuscitation (25). Therapy was open label, but the outcome assessment was blinded to treatment assignment. No differences in the 28-day mortality, need for renal replacement therapy, development of organ failure, and number of hospital days were observed between the two groups (27, 28). The 90-day mortality was slightly lower in patients who received colloids.
Based on the results of this study, we recommend conducting further studies to assess the effectiveness of controlled hypotension in different populations and age groups. The use of damage control resuscitation in critically traumatized patients should be considered to gain the benefits of early colloid resuscitation.
The limitations of this study were as follows: (1) The Small sample size may have affected the generalizability of the results. (2) We did not follow up the patients to assess the clinical outcomes at different intervals. (4) Hypothermia as an element of the lethal triad of hypothermia, coagulopathy, and acidosis didn’t assess due to unavailability of a low-reading thermometer.