850 Surgical Versus Non-Surgical Treatment of Unstable Lateral Compression Injuries of the Pelvis with Complete Sacral Fractures (LC1) in Non-Fragility Fracture Patients: A Systematic Review

Background

Lateral compression type 1 (LC1) injuries comprise two-thirds of pelvic fractures. Approximately one third of LC1 fractures are unstable and may benefit from surgical fixation to improve stability but it is not clear if this leads to better clinical or cost-effectiveness outcomes.

Method

We performed a systematic review to determine whether surgical or non-surgical treatment yielded better clinical and cost-effectiveness for the treatment of unstable LC1 pelvic injuries with complete sacral fracture, excluding fragility fractures. We searched Medline, Embase and Cochrane databases from inception to June 2021, as well as clinical trials registries.

Results

Five observational studies met the inclusion criteria. 183 patients were treated surgically, and 314 patients treated non-surgically. Patients treated surgically had lower pain levels (Visual Analogue Scale) and fewer days to mobilisation. Quality of life (EQ-5D and SF-36 questionnaires) was better in the surgical group, but not statistically significant. No statistical differences in length of hospital stay or complication rates were found. Formal meta-analysis was not possible due to available study designs and heterogeneity.

Conclusions

This review highlights the low quantity and quality of existing data on patients with unstable LC1 pelvic fractures and the need for a definitive randomised controlled trial to determine whether surgical or non-surgical care should be the preferred treatment in terms of clinical and cost-effective care.

1484 Tranexamic Acid Use to Decrease Blood Loss in Primary Shoulder and Elbow Replacement: A Systematic Review and Meta-Analysis

Tranexamic acid (TXA) is an inexpensive, commonly used antifibrinolytic agent that has been shown to significantly reduce perioperative blood loss and transfusion requirements after total hip and knee replacement. We conducted a systematic review and meta-analysis to synthesise the latest evidence regarding the effects of TXA on blood loss in total shoulder replacement (TSR) and total elbow replacement (TER).

We systematically searched MEDLINE, EMBASE and CENTRAL from inception to 03 September 2020 for randomised controlled trial (RCTs) and observational studies. Our primary outcome was blood loss, and secondary outcomes included the need for blood transfusion and venous thromboembolic (VTE) complications.

Four RCTs and five retrospective cohort studies (RCS) met eligibility criteria for TSRs, but none for TERs. RCT data determined that TXA administration significantly decreased estimated total blood loss, postoperative blood loss, change in haemoglobin (Hb) and total Hb loss when compared to placebo. RCS data demonstrated significant association between TXA administration and decreased in postoperative blood loss, change in Hb, change in Hct and length of stay.

This meta-analysis demonstrates that TXA administration in primary TSR significantly decreases blood loss compared with placebo and is associated with lower blood loss and shorter length of stay compared with no treatment with no increase in VTE complications. TXA administration should be part of a wider blood management strategy to minimise perioperative blood loss and blood transfusion requirements in patients undergoing TSR. Further research is needed to demonstrate if a similar treatment benefit exists in patients undergoing TER.

Hadean geodynamics inferred from time-varying 142Nd/144Nd in the early Earth rock record

Tracking the secular evolution of 142Nd/144Nd anomalies is important towards understanding the crust-mantle dynamics in the early Earth. Excessive scatter in the published data, however, precludes identifying the fine structure of 142Nd/144Nd evolution as the expected variability is on the order of few parts per million. We report ultra-high precision 142Nd/144Nd data for Eoarchean and Palaeoarchean rocks from the Isua Supracrustal Belt (SW Greenland) that show a well-resolved 142Nd/144Nd temporal variability suggesting progressive convective homogenisation of the Hadean Isua depleted mantle. This temporally decreasing 142Nd/144Nd signal provides a direct measure of early mantle dynamics, defining a stirring timescale of <250 Myr consistent with vigorous convective stirring in the early mantle. The 142Nd/144Nd evolution suggests protracted crustal residence times of ~1000-2000 Myr, inconsistent with modern-style plate tectonics in the Archean. In contrast, a stagnant-lid regime punctuated by episodes of mantle overturns accounts for the long life-time estimated here for the Hadean proto-crust.

Post-traumatic immunosuppression is reversed by anti-coagulated salvaged blood transfusion: deductions from studying immune status after knee arthroplasty

Major trauma increases vulnerability to systemic infections due to poorly defined immunosuppressive mechanisms. It confers no evolutionary advantage. Our objective was to develop better biomarkers of post-traumatic immunosuppression (PTI) and to extend our observation that PTI was reversed by anti-coagulated salvaged blood transfusion, in the knowledge that others have shown that non-anti-coagulated (fibrinolysed) salvaged blood was immunosuppressive. A prospective non-randomized cohort study of patients undergoing primary total knee arthroplasty included 25 who received salvaged blood transfusions collected post-operatively into acid-citrate-dextrose anti-coagulant (ASBT cohort), and 18 non-transfused patients (NSBT cohort). Biomarkers of sterile trauma included haematological values, damage-associated molecular patterns (DAMPs), cytokines and chemokines. Salvaged blood was analysed within 1 and 6 h after commencing collection. Biomarkers were expressed as fold-changes over preoperative values. Certain biomarkers of sterile trauma were common to all 43 patients, including supranormal levels of: interleukin (IL)-6, IL-1-receptor-antagonist, IL-8, heat shock protein-70 and calgranulin-S100-A8/9. Other proinflammatory biomarkers which were subnormal in NSBT became supranormal in ASBT patients, including IL-1β, IL-2, IL-17A, interferon (IFN)-γ, tumour necrosis factor (TNF)-α and annexin-A2. Furthermore, ASBT exhibited subnormal levels of anti-inflammatory biomarkers: IL-4, IL-5, IL-10 and IL-13. Salvaged blood analyses revealed sustained high levels of IL-9, IL-10 and certain DAMPs, including calgranulin-S100-A8/9, alpha-defensin and heat shock proteins 27, 60 and 70. Active synthesis during salvaged blood collection yielded increasingly elevated levels of annexin-A2, IL-1β, Il-1-receptor-antagonist, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p70, IL-17A, IFN-γ, TNF-α, transforming growth factor (TGF)-β1, monocyte chemotactic protein-1 and macrophage inflammatory protein-1α. Elevated levels of high-mobility group-box protein-1 decreased. In conclusion, we demonstrated that anti-coagulated salvaged blood reversed PTI, and was attributed to immune stimulants generated during salvaged blood collection.

Oily adjuvants and autoimmunity: now time for reconsideration?

Immunologists have relied heavily on oil-based adjuvants to generate antibodies or induce auto-allergic responses in experimental animals. These are rarely used today for human vaccination because of their persistent irritancies and propensity to cause ulcers at sites of injection. However oily materials with adjuvant properties abound in our modern environment, both personal and extraneous. Their inadvertent impact as cryptotoxins may contribute to the rising incidence of auto-allergic diseases in recent times. Experimentally, the potential adjuvanticity of various oils, fats and other lipids can be evaluated by their ability (or otherwise) to induce auto-allergic disease(s) in rats and mice with, or even without, the addition of a mycobacterial immunostimulant. Genetic factors have been recognized that determine an animal's susceptibility or resistance to these oil-induced immunopathies. So it may be profitable to further characterize these factors, first in animals and then perhaps in human populations, to help find ways to enhance natural resistance to those adjuvant-active oils that may be widely distributed in the personal environment, notably mineral oil(s). (The six tables in this article summarize some relevant facts and a few conjectures.) A caveat: This review is restricted to the adjuvant properties of some oils in the personal environment. It does not cover the mechanisms of adjuvanticity.

The use of lubrication in flexible fibreoptic nasendoscopy: a randomized controlled trial

OBJECTIVES

To determine how lubrication of the endoscope prior to flexible fibreoptic nasendoscopy affects levels of patient discomfort and pain during endoscopy. To assess the extent to which lubrication affects the ease of nasendoscopy and the quality of the image obtained.

DESIGN

Single blind, randomized controlled trial.

SETTING

Outpatient clinic of the Department of Otolaryngology at a secondary level referral centre.

PARTICIPANTS

A total of 150 participants selected sequentially from patients requiring a nasendoscopy where the endoscope would be passed far enough to view the larynx. Patients requiring topical anaesthetic were excluded. All participants who were entered in the study completed the study. Endoscopy was performed by all grades of medical staff.

MAIN OUTCOMES MEASURES

Levels of discomfort and pain experienced by the participants were assessed by a visual analogue scale (VAS). Difficulty of passing the scope was indicated by the endoscopist using a VAS, as was the quality of image obtained.

RESULTS

There was no significant difference between mean scores for pain or discomfort of the lubricated and unlubricated groups (P = 0.46 and P = 0.82 respectively). Scores for difficulty of passing the scope were significantly lower in the lubricant group (P = 0.003) but loss of image was significantly greater (P = 0.008).

CONCLUSIONS

Lubrication of the endoscope prior to nasendoscopy does not reduce levels of discomfort or pain for the patient, but increases ease in insertion for the operator. However, this may be at the expense of reduced image quality.

Coxibs and their aftermath: an (opinionated) commentary, based on some historical viewpoints

Five historical viewpoints are presented, each foreshadowing to some degree that it was only a matter of time before we would (re)learn that imbalanced anti-prostanoid therapy was a potentially lethal strategy. Positive outcomes from this coxib debacle might be more willingness to (i) acknowledge our lack of understanding concerning normal homeostatic mechanisms involving the autopharmacology and pleiotropic functions of prostanoids and acyclic eicosanoids (leukotrienes, lipoxins, resolvins, etc.); (ii) revisit the question of salicylate versus aspirin for therapies not requiring anti-thrombotic prophylaxis; (iii) re-examine some leads provided by natural/alternate therapies for inflammatory disorders; and (iv) reconsider the downside of over-reliance upon the present patent system as the main shield and driver of drug innovation.

New field, structural and geochronological data from the Shyok and Nubra valleys, northern Ladakh: linking Kohistan to Tibet

The Nubra-Shyok confluence in northern Ladakh is a key area for understanding the tectonic evolution of NW Himalaya and provides the basis for linking the geology of Pakistan to that of Tibet. The geology of the confluence area has been the subject of much speculation centred mainly on the existence of ophiolites and their regional significance. These ophiolites are thought to represent the eastward extension of the Shyok Suture Zone (SSZ), which separates the Dras island arc from the southern margin of Eurasia, and which was overprinted by movement along the Khalsar Thrust (often thought to represent the eastern continuation of the Main Karakoram Thrust). The geology of the area is relatively complex and the little information available has hampered regional geological correlations.

The Khalsar Thrust (KT) and the dextral Karakoram Fault (KF), two regional tectonic features of NW Himalaya, merge at the confluence defining a triple point and three blocks: the Ladakh block to the south, the Saltoro block to the northwest, and the Karakoram block to the northeast. Close to the triple point, the KF changes strike and movement direction. Movement vector analysis of the triple point indicates that the KT and the two parts of the KF could have moved contemporaneously, and allows prediction of the movement vectors across the faults. The KT and KF shear preferentially volcano-sedimentary rocks of the Shyok and Nubra formations, respectively. Contrary to previous interpretations, these sheared rocks do not represent disrupted ophiolites. Regional tectonic reconstructions, however, require suturing between the Ladakh block and Eurasia and the strike of the SSZ in Baltistan suggests that the suture zone might crop out north of the KT, either along the southern slopes of the Saltoro Range or further north along the Saltoro valley. In the few outcrops of the Saltoro block we were able to visit, we found no evidence of ophiolitic rocks. Instead we found outcrops of the calc-alkaline Tirit batholith. Although our observations do not confirm the presence of the suture-related rocks in the southern Saltoro block, this possibility cannot be ruled out. Zircons from a sample of Tirit granite (U-Pb ion-microprobe age) yielded an age centred at 68 ± 1 Ma. The similar range of modal composition and age of the Tirit and Ladakh batholiths suggest that they are part of the same magmatic event. This result and a number of other observations indicate that the post-75 Ma geology of the Ladakh and Saltoro blocks is similar. Thus, if there is a suture zone in the southern Saltoro block, suturing must have occurred before 75 Ma, as concluded by others along the same tectonic boundary to the west in Pakistan.

The KF represents a much younger terrane boundary, juxtaposing rocks of the Ladakh and Saltoro blocks to those of the Karakoram terrane. Rocks related to suturing of continents were not found along the KF. Karakoram leucogranites cropping out in the southern part of Karakoram terrane yielded a U-Pb zircon age centred at 15.0 ± 0.4 Ma (2σ). Because these leucogranites were not found south of the KF, this fault must have initiated after leucogranite intrusion and must therefore be younger than 15 Ma old. At the confluence the KF cuts across the regional rock sequence than can be followed from Kohistan into Baltistan and into the confluence area. Movement on the fault displaces the sequence by approximately 150 km to southeastern Tibet where the regional rock sequence can be regained.

Significance of intracranial pressure waveform analysis after head injury

The authors have investigated the relationships between the amplitude of the ICP pulse wave, the mean values of ICP and CPP, and the outcome of 56 head injured ventilated patients. The ICP was monitored continuously using a Camino transducer (35 patients) or subdural catheter (21 patients). The mean Glasgow Coma Score was 6 (range 3-13; 5 patients had a GCS > 8 after resuscitation). Patients were grouped according to their Glasgow Outcome Score assessed at 12 months after injury. The amplitude of ICP pulse waveform was assessed using the fundamental harmonic of the pulse waveform (AMP) to avoid distortion caused by different frequency responses of the pressure transducers used in the study. Statistical analysis revealed that in patients with fatal outcome the ICP pulse amplitude increased when the mean ICP increased to 25 mmHg and then began to decrease. The upper breakpoint of the AMP-ICP relationship was not present in patients with good/moderate outcome. The moving correlation coefficient between the fundamental harmonic of ICP pulse wave and the mean ICP (RAP: R-symbol of correlation between A-amplitude and P-pressure) was introduced to describe the time-dependent changes in correlation between amplitude and mean ICP. The RAP was significantly lower in patients who died or remained in the vegetative state. In 7 patients who died from uncontrollable intracranial hypertension RAP was oscillating or decreased to 0 or negative values well before brain-stem herniation. The combination of an ICP above 20 mmHg for a period longer than 6 hours with low correlation between the amplitude and pressure (RAP < 0.5) was described as an predictive index of an unfavourable outcome.

A rare case of a false-negative finding in both direct and culture of a chorionic villus sample

A discrepancy is reported between the karyotype of both direct and cultured chorionic villus cells (46,XX) and a fetal skin biopsy (47,XX, +18). The significance of this result is discussed and compared with similar discordant findings reported in the literature.

Chemotherapy of advanced ovarian carcinoma: initial experience using a platinum-based combination

Thirty-five previously untreated patients with FIGO Stage III or IV ovarian carcinoma were treated with cis-diamminedichloroplatinum (II), Adriamycin and cyclophosphamide (PACe). Following four or five cycles of PACe, patients were assessed clinically for response. Twenty-one (60%) of the patients attained a clinical complete remission (CCR), seven (20%) a partial remission, and seven (20%) did not respond. The median survival of all patients was 19 months, 6.4 months for partial and nonresponders, and 26.5 months for clinical complete responders. Six patients remain relapse-free for more than two years. Patients entering into the study during the second year underwent a second-look procedure if they attained a CCR. Ten patients in CCR were assessed for second look; two refused, and eight underwent a laparotomy. Three of eight were in complete remission after second look, and a fourth patient who had microscopic disease in one ovary was rendered free of disease by surgery. Subjective toxicity was marked due to severe nausea and vomiting. Renal toxicity was not troublesome and myelosuppression was moderate. Ototoxicity and peripheral neuropathies were seen in seven patients. PACe is a highly effective induction regime but randomized studies are required to show that improved survival will result from it's use.

Irritancy of cyclophosphamide-derived aldehydes (acrolein, chloracetaldehyde) and their effect on lymphocyte distribution in vivo: protective effect of thiols and bisulphite ions1)

(1) A strategy is described for investigating agents such as N-acetylcysteine or penicillamine that might be used as adjuvant therapy with cyclophosphamide, to lessen the toxic side-effects of this latter drug caused by some of its metabolites. (2) The toxic effects of acrolein and chloracetaldehyde were determined by (a) their effects on lymphocyte circulation and (b) their oedemagenic activity in rats. (3) Stable thiols and bisulphite ions antagonised this aldehyde toxicity/irritancy; thiosulphate ions did not. (4) Thiosulphate and bisulphite ions antagonised the irritancy/toxicity of a mustard, mechlorethamine (HN-2). (5) The possible relationship of intrinsic irritancy to anti-inflammatory activity is discussed briefly.