Continuous Noninvasive Hemoglobin Monitor from Pulse Ox: Ready for Prime Time?

Background

Advances in technology have allowed for continuous noninvasive hemoglobin monitoring (SpHb), which may enable earlier detection of hemorrhage and more efficient surgical and/or blood transfusion management. The use of SpHb has not been described in the trauma population. The purpose of the present study was to evaluate the accuracy of a SpHb measurement device in severely injured trauma patients.

Methods

We performed a prospective cohort analysis of severely injured trauma patients admitted to the intensive care unit (ICU) at our level I trauma center over a 6 month period. Serial IHb (invasive hemoglobin) levels and SpHb for the first 72 h were measured. Each SpHb measurement was matched with a corresponding IHb measurement. We defined normal Hgb as >8 mg/dL and low Hgb as <8 mg/dL. Data were then grouped based on Hgb level. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy, and Spearman correlation coefficient plot were calculated.

Results

A total of 23 trauma patients with 89 data pairs were reviewed. Eighty-six percent of the patients were male with a mean age of 32 years and a mean injury severity score (ISS) of 21.1 ± 14. Invasive hemoglobin had a range of 7.2–16.9 and SpHb had a range of 3.3–15.2. The average mean and difference between IHb and SpHb were 10.7 and 1, respectively. Continuous noninvasive hemoglobin measurement did not record data points 13.5 % of the time. The Spearman correlation plot revealed a correlation of R = 0.670 (p < 0.001). After dichotomization with Hgb > 8, SpHb was found to have a sensitivity of 91 %, PPV 96 %, specificity 40 %, NPV 20 %, and an accuracy of 88 %.

Conclusions

The continuous noninvasive hemoglobin monitor does not appear to represent serum hemoglobin levels accurately in severely injured trauma patients. However, we were able to identify utility for this noninvasive tool when Hgb was dichotomized into normal or low levels.     

Significant enhancement of dielectric permittivity and percolation behaviour of La2−xSrxNiO4/poly(vinylidene fluoride) composites with different Sr doping concentrations

The percolation behaviour and dielectric properties of La_2−xSr_xNiO₄ (LSNO)/poly(vinylidene fluoride) (PVDF) composites with different Sr doping concentrations were investigated. The semiconducting LSNO filler particles with x = 0.2 (LSNO-1) and x = 0.4 (LSNO-2) were prepared using a chemical combustion method. The microstructures, thermal properties, and phase compositions of the polymer composites and filler particles were systematically investigated. The conductivity of the LSNO fillers increased with the Sr content and had an important impact on the dielectric properties of the LSNO/PVDF composites. The percolation threshold of the LSNO-2/PVDF composite was lower than that of the LSNO-1/PVDF composite. An ultra-high dielectric permittivity (ε′) of 3384.7 (at 1 kHz and room temperature), which was approximately 340 times higher than that of pure PVDF, was obtained for the LSNO-2/PVDF composite with a filler volume fraction of 25 vol%. The enhanced dielectric properties were attributed to interfacial polarisation at the semiconductor–insulator interface, a micro-capacitor model, and the intrinsically remarkable dielectric properties of the LSNO ceramic.

The percolation behaviour and dielectric properties of La_2−xSr_xNiO₄ (LSNO)/poly(vinylidene fluoride) (PVDF) composites with different Sr doping concentrations were investigated.     

Prothrombin Complex Concentrate Versus Fresh-Frozen Plasma for Reversal of Coagulopathy of Trauma: Is There a Difference?

Introduction

The development of coagulopathy of trauma is multifactorial associated with hypoperfusion and consumption of coagulation factors. Previous studies have compared the role of factor replacement versus FPP for reversal of trauma coagulopathy. The purpose of our study was to determine the time to correction of coagulopathy and blood product requirement in patients who received PCC+FFP compared with patients who received FFP alone.

Methods

We performed a retrospective analysis of a prospectively maintained database of all coagulopathic (INR ≥ 1.5) trauma patients presenting to our level I trauma center during a 2-years period (2011–2012). Patients were stratified into two groups: patients who received PCC+FFP and patients who received FFP alone. Patients in the two groups were matched in a 1:3 (PCC+FFP:FFP) ratio using propensity score matching for demographics, injury severity, vital parameters, and initial INR. The two groups were then compared for: correction of INR, time to correction of INR, thromboembolic complications, mortality, and cost of therapy.

Results

A total of 252 were included in the analysis [PCC+FFP:63; FFP:189]. The mean age was 44 ± 20 years; 70 % were male, with a median ISS score of 27 [16–38]. PCC use was associated with an accelerated correction of INR (394 vs. 1,050 min; p 0.001), reduction in requirement of pack red blood cell (6.6 vs. 10 units; p 0.001) and FFP (2.8 vs. 3.9 units; p 0.01), and decline in mortality (23 vs. 28 %; p 0.04). PCC+FFP use was associated with a higher cost of therapy ($1,470 ± 845 vs. 1,171 ± 949; p 0.01) but lower overall cost of transfusion ($7,110 ± 1,068 vs. 9,571 ± 1,524; p 0.01) compared with FFP therapy alone.

Conclusions

PCC in conjunction with FFP rapidly corrects INR in a matched cohort of trauma patients not on warfarin therapy compared with FFP therapy alone. The use of PCC as an adjunct to FFP therapy is associated with reduction of blood product requirement and also lowers overall cost.     

Management of acute mild gallstone pancreatitis under acute care surgery: should patients be admitted to the surgery or medicine service?

Background

We hypothesized that patients with acute mild gallstone pancreatitis (GSP) admitted to surgery (SUR; vs medicine [MED]) had a shorter time to surgery, shorter hospital length of stay (HLOS), and lower costs.

Methods

We performed chart reviews of patients who underwent a cholecystectomy for acute mild GSP from October 1, 2009 to May 31, 2013. We excluded patients with moderate to severe and non-gallstone pancreatitis. We compared outcomes for time to surgery, HLOS, costs, and complications between the 2 groups.

Results

Fifty acute mild GSP patients were admitted to MED and 52 to SUR. MED patients were older and had more comorbidity. SUR patients had a shorter time to surgery (44 vs 80 hours; P < .001), a shorter HLOS (3 vs 5 days; P < .001), and lower hospital costs ($11,492 ± 6,480 vs $16,183 ± 12,145; P = .03). In our subgroup analysis on patients with an American Society of Anesthesiologists score between 1 and 2, the subgroups were well matched; all outcomes still favored SUR patients.

Conclusions

Admitting acute mild GSP patients directly to SUR shortened the time to surgery, shortened HLOS, and lowered hospital costs.     

Mortality after trauma laparotomy in geriatric patients

Background

Geriatric patients are at higher risk for adverse outcomes after injury because of their altered physiological reserve. Mortality after trauma laparotomy remains high; however, outcomes in geriatric patients after trauma laparotomy have not been well established. The aim of our study was to identify factors predicting mortality in geriatric trauma patients undergoing laparotomy.

Methods

A retrospective study was performed of all trauma patients undergoing a laparotomy at our level 1 trauma center over a 6-y period (2006–2012). Patients with age ≥55 y who underwent a trauma laparotomy were included. Patients with head abbreviated injury scale (AIS) score ≥ 3 or thorax AIS ≥ 3 were excluded. Our primary outcome measure was mortality. Significant factors in univariate regression model were used in multivariate regression analysis to evaluate the factors predicting mortality.

Results

A total of 1150 patients underwent a trauma laparotomy. Of which 90 patients met inclusion criteria. The mean age was 67 ± 10 y, 63% were male, and median abdominal AIS was 3 (2–4). Overall mortality rate was 23.3% (21/90) and progressively increased with age (P = 0.013). Age (P = 0.02) and lactate (P = 0.02) were the independent predictors of mortality in geriatric patients undergoing laparotomy.

Conclusions

Mortality rate after trauma laparotomy increases with increasing age. Age and admission lactate were the predictors of mortality in geriatric population undergoing trauma laparotomies.     

Surgical management of perihilar cholangiocarcinoma: a Khon Kaen experience

Cholangiocarcinoma is the most common cancer in the northeast of Thailand. Most of the patients present when the disease is in an advanced stage. Improvement of preoperative diagnoses and surgical techniques provide more satisfactory results. Herein we reviewed our 30‐year experience in management of perihilar cholangiocarcinoma in Khon Kaen northeast Thailand. Between 1982 and 2012 we reviewed four specific studies of perihilar cholangiocarcinoma in Srinagarind Hospital, Khon Kaen, Thailand. The first study focused on advanced surgical pathology and palliative surgery, which were used to treat obstructive jaundice cholangiocarcinoma patients. Long‐term survival in this study was rare with a one‐year survival of just 15%. The second study was conducted on 30 consecutive cases of perihilar cholangiocarcinoma who presented with obstructive jaundice without preoperative biliary drainage. All the patients underwent major liver resection with bilio‐enteric reconstruction. Perioperative mortality was 6.7% without a 5‐year survival. The third study aimed to analyze the survival rates and factors affecting survival in extrahepatic CCA patients following surgical treatment at Srinagarind Hospital and concluded that resection margins are an important prognostic factor. The last study objective was the analysis of curative surgical attempt in 99 consecutive perihilar cholangiocarcinoma and results showed that R0 resection could improve long‐term survival. We evaluated four studies of perihilar cholangiocarcinoma in Srinagarind Hospital, Khon Kaen, Thailand from 1982–2012. Viewed chronologically there has been a progressive improvement of diagnosis and surgical treatment during the past 30 years. Despite these advances the 5‐year survival rate remains unsatisfactorily low. Future improvement of patient selection and surgical techniques can lead to a greater survival rate for patients.     

Helicobacter pylori in Thai patients with cholangiocarcinoma and its association with biliary inflammation and proliferation

Objectives

To investigate whether Helicobacter spp. infection and the cagA of H. pylori are associated with hepatobiliary pathology, specifically biliary inflammation, cell proliferation and cholangiocarcinoma (CCA).

Methods

Helicobacter species including H. pylori, H. bilis and H. hepaticus were detected in the specimens using the polymerase chain reaction (PCR). Biliary inflammation of the liver and gallbladders was semi-quantitatively graded on hematoxylin and eosin (H&E)-stained slides. Biliary proliferation was evaluated by immunohistochemistry using the Ki-67-labelling index.

Results

Helicobacter pylori was found in 66.7%, 41.5% and 25.0% of the patients in the CCA, cholelithiasis and control groups (P < 0.05), respectively. By comparison, H. bilis was found in 14.9% and 9.4% of the patients with CCA and cholelithiasis, respectively (P > 0.05), and was absent in the control group. The cagA gene of H. pylori was detected in 36.2% and 9.1% of the patients with CCA and cholelithiasis, respectively (P < 0.05). Among patients with CCA, cell inflammation and proliferation in the liver and gallbladder were significantly higher among those DNA H. pylori positive than negative.

Conclusions

The present findings suggest that H. pylori, especially the cagA-positive strains, may be involved in the pathogenesis of hepatobiliary diseases, especially CCA through enhanced biliary cell inflammation and proliferation.     

In vitro fracture strength of teeth restored with different all-ceramic crown systems

STATEMENT OF PROBLEM: There is insufficient knowledge of the strength of all-ceramic crowns bonded to natural teeth to warrant the use of all-ceramic crowns in place of metal-ceramic crowns. PURPOSE: The purpose of this study was to evaluate and compare fracture resistance of crowns made of 3 different types of 2 all-ceramic crown systems-0.4-mm and 0.6-mm aluminum oxide coping crowns and zirconia ceramic coping crowns-and metal-ceramic crowns. MATERIAL AND METHODS: Forty intact, noncarious human maxillary central incisors were divided into 4 groups (n=10): Group MCC (control), metal-ceramic crown (JRVT High Noble Alloy); Group AC4, crown with 0.4-mm aluminum oxide coping (Procera AllCeram); Group AC6, crown with 0.6-mm aluminum oxide coping (Procera AllCeram); and Group ZC6, crown with 0.6-mm zirconia ceramic coping (Procera AllZirkon). Teeth were prepared for complete-coverage all-ceramic crowns so that a final dimension of 5.5 +/- 0.5 mm was achieved incisocervically, mesiodistally, and faciolingually. A 1.0-mm deep shoulder finish line was used with a rounded internal line angle. All restorations were treated with bonding agent (Clearfil SE Bond) and luted with phosphate-monomer-modified adhesive cement (Panavia 21). Fracture strength was tested with a universal testing machine at a crosshead speed of 2 mm per minute with an angle of 30 degrees to the long axis of the tooth after restorations were stored in 100% relative humidity of a normal saline solution for 7 days. The mode of fracture was examined visually. Means were calculated and analyzed with 1-way ANOVA and Tukey's HSD (alpha=.05). RESULTS: The means of fracture strength were: Group MCC, 405 +/- 130 N; Group AC4, 447 +/- 123 N; Group AC6, 476 +/- 174 N; and Group ZC6, 381 +/- 166 N. There was no significant difference between groups ( P =.501). The mode of failure for all specimens was fracture of the natural tooth. CONCLUSIONS: There was no significant difference in the fracture strength of the teeth restored with all-ceramic crowns with 0.4- and 0.6-mm aluminum oxide copings, 0.6-mm zirconia ceramic copings, and metal ceramic crowns.