Christopher Cheung, MD

All Publications

• Use of a Sheath and Stylet for a Difficult Dorsal Root Ganglion Stimulation Lead Extraction: A Case Report. A&A practice Cheung, C. K., Lee, K. W., Yong, R. J. 2024; 18 (3): e01766

  Abstract

  Dorsal root ganglion stimulation (DRG-S) is a relatively new neuromodulation technique that has shown promising results in the treatment of chronic pain conditions. We present a case of a difficult lead extraction during the explantation of a DRG-S device. The lead was unable to be removed despite multiple attempts until a sheath and stylet were used to facilitate extraction. As DRG-S utilization becomes more widespread, DRG-S device explantation will inevitably become more common. The technique described in this report may be beneficial in certain cases of difficult DRG-S lead extraction.

  View details for DOI 10.1213/XAA.0000000000001766

  View details for PubMedID 38502524

• Postoperative Pain Management in Enhanced Recovery Pathways. Journal of pain research Cheung, C. K., Adeola, J. O., Beutler, S. S., Urman, R. D. 2022; 15: 123-135

  Abstract

  Postoperative pain is a common but often inadequately treated condition. Enhanced recovery pathways (ERPs) are increasingly being utilized to standardize perioperative care and improve outcomes. ERPs employ multimodal postoperative pain management strategies that minimize opioid use and promote recovery. While traditional opioid medications continue to play an important role in the treatment of postoperative pain, ERPs also rely on a wide range of non-opioid pharmacologic therapies as well as regional anesthesia techniques to manage pain in the postoperative setting. The evidence for the use of these interventions continues to evolve rapidly given the increasing focus on enhanced postoperative recovery. This article reviews the current evidence and knowledge gaps pertaining to commonly utilized modalities for postoperative pain management in ERPs.

  View details for DOI 10.2147/JPR.S231774

  View details for PubMedID 35058714

  View details for PubMedCentralID PMC8765537

• Lung Microbiota Is Related to Smoking Status and to Development of Acute Respiratory Distress Syndrome in Critically Ill Trauma Patients. American journal of respiratory and critical care medicine Panzer, A. R., Lynch, S. V., Langelier, C., Christie, J. D., McCauley, K., Nelson, M., Cheung, C. K., Benowitz, N. L., Cohen, M. J., Calfee, C. S. 2018; 197 (5): 621-631

  Abstract

  Cigarette smoking is associated with increased risk of acute respiratory distress syndrome (ARDS) in patients after severe trauma; however, the mechanisms underlying this association are unknown.To determine whether cigarette smoking contributes to ARDS development after trauma by altering community composition of the lung microbiota.We studied the lung microbiota of mechanically ventilated patients admitted to the ICU after severe blunt trauma. To do so, we used 16S ribosomal RNA gene amplicon sequencing of endotracheal aspirate samples obtained on ICU admission (n = 74) and at 48 hours after admission (n = 30). Cigarette smoke exposure (quantified using plasma cotinine), ARDS development, and other clinical parameters were correlated with lung microbiota composition.Smoking status was significantly associated with lung bacterial community composition at ICU admission (P = 0.007 by permutational multivariate ANOVA [PERMANOVA]) and at 48 hours (P = 0.03 by PERMANOVA), as well as with significant enrichment of potential pathogens, including Streptococcus, Fusobacterium, Prevotella, Haemophilus, and Treponema. ARDS development was associated with lung community composition at 48 hours (P = 0.04 by PERMANOVA) and was characterized by relative enrichment of Enterobacteriaceae and of specific taxa enriched at baseline in smokers, including Prevotella and Fusobacterium.After severe blunt trauma, a history of smoking is related to lung microbiota composition, both at the time of ICU admission and at 48 hours. ARDS development is also correlated with respiratory microbial community structure at 48 hours and with taxa that are relatively enriched in smokers at ICU admission. The data derived from this pilot study suggest that smoking-related changes in the lung microbiota could be related to ARDS development after severe trauma.

  View details for DOI 10.1164/rccm.201702-0441OC

  View details for PubMedID 29035085

  View details for PubMedCentralID PMC6005235

• Inducing Acute Traumatic Coagulopathy In Vitro: The Effects of Activated Protein C on Healthy Human Whole Blood. PloS one Howard, B. M., Kornblith, L. Z., Cheung, C. K., Kutcher, M. E., Miyazawa, B. Y., Vilardi, R. F., Cohen, M. J. 2016; 11 (3): e0150930

  Abstract

  Acute traumatic coagulopathy has been associated with shock and tissue injury, and may be mediated via activation of the protein C pathway. Patients with acute traumatic coagulopathy have prolonged PT and PTT, and decreased activity of factors V and VIII; they are also hypocoagulable by thromboelastometry (ROTEM) and other viscoelastic assays. To test the etiology of this phenomenon, we hypothesized that such coagulopathy could be induced in vitro in healthy human blood with the addition of activated protein C (aPC).Whole blood was collected from 20 healthy human subjects, and was "spiked" with increasing concentrations of purified human aPC (control, 75, 300, 2000 ng/mL). PT/PTT, factor activity assays, and ROTEM were performed on each sample. Mixed effect regression modeling was performed to assess the association of aPC concentration with PT/PTT, factor activity, and ROTEM parameters.In all subjects, increasing concentrations of aPC produced ROTEM tracings consistent with traumatic coagulopathy. ROTEM EXTEM parameters differed significantly by aPC concentration, with stepwise prolongation of clotting time (CT) and clot formation time (CFT), decreased alpha angle (α), impaired early clot formation (a10 and a20), and reduced maximum clot firmness (MCF). PT and PTT were significantly prolonged at higher aPC concentrations, with corresponding significant decreases in factor V and VIII activity.A phenotype of acute traumatic coagulopathy can be induced in healthy blood by the in vitro addition of aPC alone, as evidenced by viscoelastic measures and confirmed by conventional coagulation assays and factor activity. This may lend further mechanistic insight to the etiology of coagulation abnormalities in trauma, supporting the central role of the protein C pathway. Our findings also represent a model for future investigations in the diagnosis and treatment of acute traumatic coagulopathy.

  View details for DOI 10.1371/journal.pone.0150930

  View details for PubMedID 27008408

  View details for PubMedCentralID PMC4805205

• The whole is greater than the sum of its parts: hemostatic profiles of whole blood variants. The journal of trauma and acute care surgery Kornblith, L. Z., Howard, B. M., Cheung, C. K., Dayter, Y., Pandey, S., Busch, M. P., Pati, S., Callcut, R. A., Vilardi, R. F., Redick, B. J., Nelson, M. F., Cohen, M. J. 2014; 77 (6): 818-27

  Abstract

  Mounting evidence highlighting the benefits of hemostatic resuscitation has led to a renewed interest in whole blood (WB) and reconstituted WB (RWB). However, few data exist to characterize the clotting profiles of these variants. This study characterizes banked WB variants and RWB in standard 1:1:1 and 2:1:1 transfusion ratios of packed red blood cells, fresh frozen plasma, and platelets (PLTs). We hypothesized that the global hemostatic profile of 1:1:1 RWB is superior to 2:1:1 RWB and that PLT-modified WB (MWB) is superior to 1:1:1 RWB.Twenty-three units of packed red blood cells, fresh frozen plasma, and PLTs were obtained from the regional blood collection center and mixed to create 23 1:1:1 and 23 2:1:1 RWB units. Freshly donated WB units were obtained and used to create 11 of each nonmodified WB (NMWB) (room temperature and cooled) and MWB (room temperature and cooled) variants. International normalized ratio (INR)/partial thromboplastin time (PTT), complete blood cell count, functional studies, and an extensive panel of procoagulant and anticoagulant factor assays were performed on all products.The 1:1:1 RWB had significantly lower INR and PTT (1.31 vs. 1.55, p = 0.0029; 42 seconds vs. 50 seconds, p = 0.0008) and higher activity of factors II, V, VII, VIII, IX, and X; antithrombin III, as well as protein C and higher fibrinogen levels than did 2:1:1 RWB (factor IX, 86% vs. 70%, p = 0.0313; fibrinogen, 242 mg/dL vs. 202 mg/dL, p = 0.0385). There were no differences in INR/PTT or factor activity between MWB and NMWB. However, MWB had greater maximum clot firmness (MCF) by rotational thromboelastometry tissue factor-activated extrinsic clotting cascade measures than did NMWB (MCF, 61 mm vs. 50 mm, p = 0.0031). MWB also had greater MCF by rotational thromboelastometry tissue factor-activated extrinsic clotting cascade measures than did 1:1:1 RWB (MCF, 61 mm vs. 45 mm, p = 0.0005).Although 1:1:1 RWB had a superior clotting profile relative to 2:1:1 RWB, MWB exhibited even better global hemostasis than did 1:1:1 RWB. Characterization of factor-level and functional clotting differences between WB variants is imperative for understanding the clinical benefits of hemostatic resuscitation.

  View details for DOI 10.1097/TA.0000000000000354

  View details for PubMedID 25051379