January 2024 Critical Care Case of the Month: I See Tacoma

Lewis J. Wesselius MD

Mayo Clinic Arizona, Scottsdale, AZ USA

History of Present Illness

An 80-year-old man was admitted to the hospital for exacerbation of COPD. He has a history of emphysema and has been on Breo Ellipta and Spiriva Respimat. He became increasingly short of breath although he had no productive cough.

Past Medical History, Social History and Family History

He has a past medical history of right upper lobe resection for an adenocarcinoma of the lung and a history of coronary artery bypass grafting and aortic valve replacement done about 5 years ago.

He smoked ½ pack/day of cigarettes but quit 5 years ago.

Medications

He takes warfarin for a history of atrial fibrillation and prosthetic aortic valve replacement.

Physical Examination

Other than dyspnea with tachypnea and decreased air movement on auscultation, as well as the expected right thoracic scar, his physical examination is unremarkable.

Laboratory

His arterial blood gases showed a PaO2 of 58, a PaCO2 of 32, and a pH of 7.50 on 2L/min by nasal cannula. Complete blood count, electrolytes were normal. Prothrombin time was therapeutic.

Radiography

Chest x-ray taken in the emergency department is shown in Figure 1.

Figure 1. Initial PA of chest.

What should be done at this time? (click on the correct answer to be directed to the second of five pages)

1. Admit to the hospital
2. Begin on a theophylline drip
3. Treat with inhaled bronchodilators, oral antibiotics and corticosteroids
4. 1 and 3
5. All of the above

Wesselius LJ. January 2024 Critical Care Case of the Month: I See Tacoma. Southwest J Pulm Crit Care Sleep. 2024;28(1):1-4. doi: https://doi.org/10.13175/swjpccs051-23 PDF 

Management of Life Threatening Post-Partum Hemorrhage with HBOC-201 in a Jehovah’s Witness

Andrea Mytinger, DO¹

Elyce Sheehan, MD¹

Nathan Blue, MD²

Kendall P. Crookston, MD, PhD³

Ali I. Saeed, MD ⁴

¹Department of Internal Medicine, ²Department of Maternal and Fetal Medicine, ³Departments of Pathology of Transfusion Medicine, and ⁴Divisions of Pulmonary, Sleep and Critical Care Medicine

University of New Mexico School of Medicine

Albuquerque, NM USA

Abstract

Background: Post-partum hemorrhage remains the leading cause of maternal mortality worldwide. The obstetrician and critical care physician should be aware of local alternative treatment options for symptomatic anemia secondary to post-partum hemorrhage in patients who cannot receive red blood cell transfusion. Transfusion may not be an option due to strong personal belief, lack of compatible blood, or blood shortage.

Case: A 21-year-old woman, gravida 1 para 1001, was transferred to a tertiary care center for management of severe post-partum hemorrhage (hemoglobin 4.2 g/dL). She had undergone emergent dilation and curettage followed by Bakri tamponade balloon placement at an outside facility. As a member of the Jehovah’s Witness faith, she refused red blood cell transfusion. HBOC-201, a bovine hemoglobin based oxygen carrier, was successfully used to reverse symptomatic, life-threatening anemia.

Conclusion:  HBOC-201 can act as a means to reverse severe end-organ damage for patients with severe post-partum hemorrhage and should be considered when no other treatment options are available.

Teaching Points

1. HBOC-210 (Hemopure®) is a bovine hemoglobin-based oxygen carrier (HBOC), used as a means to reverse severe anemia in those patients who cannot receive RBC transfusion.
2. The current generation of HBOCs carry fewer side effects than their predecessors. Common side effects include transient hypertension, abdominal complaints, jaundice, elevated liver and pancreatic enzymes and decreased urine output.
3. The teratogenic effects of HBOC-201 remains unknown in humans.

Introduction

Worldwide, there are an estimated 14 million pregnancy-related hemorrhages each year and 25% of maternal mortality can be attributed to post-partum hemorrhage (1). While the majority of post-partum hemorrhage leading to acute blood loss anemia is treated with red blood cell (RBC) transfusion, there remains a significant subset of patients who are unable to receive this life-saving modality. In instances where RBC transfusion is not an option due to lack of compatible blood, blood shortage, or strong patient personal beliefs, there remain alternative options for management. We report the case of a young Jehovah’s Witness who presented with symptomatic anemia secondary to severe post-partum hemorrhage, treated successfully with an experimental protocol using HBOC-201 (Hemopure®).

Case

A 21-year-old female, gravida 1 para 1001, Jehovah’s Witness was transferred to a tertiary care hospital for management of post-partum hemorrhage after spontaneous vaginal delivery at 40 weeks of gestation. The patient received 3 boluses of intravenous oxytocin, 800mcg of misoprostol and 1 dose of intramuscular (IM) carboprost trimethamine. She then underwent a dilation and curettage for presumed retained products of conception. A Bakri tamponade balloon catheter (Figure 1) was placed vaginally and the patient was transferred for a higher level of care.

Figure 1.  An example illustration of the Bakri vaginal tamponade balloon, placed in the uterus in attempt to apply pressure to bleeding vessels.

Prior to delivery, the patient’s hemoglobin (Hb) and hematocrit (Hct) were initially 12.4 g/dL and 36.4 %, respectively, which decreased to 5.5 g/dL and 16.4%.

On arrival, the patient ‘s heart rate was 148 beats per minute while on 2L of oxygen. The blood pressure was 93/36 mmHg. She was pale and tired-appearing with conjunctival pallor.  Her abdomen exhibited generalized mild tenderness to palpation. The Bakri balloon was in place with 100 mL of drainage noted. Laboratory results revealed Hb of 4.2 g/dL, lactate of 1.2 mmol/L and troponin I of 1.820 ng/mL. The patient refused transfusion of RBC, and the other major blood products, citing her faith. After a prolonged discussion, the patient consented to the use of HBOC-201.

The patient received 2 units of HBOC-201 along with 1,000 mg of ascorbic acid. Her Hb increased from 4.2 g/dL to 4.8 g/dL, much less than the anticipated 1 g/dL increase with each unit of HBOC-201 raising concern for ongoing hemorrhage. An ultrasound was performed which revealed ongoing bleeding from the lower uterine segment behind the balloon. Methylergonovine 0.2mg IM every 6 hours was started and the patient received two additional units of HBOC-201 however, during infusion of the second unit her oxygen requirement increased from 2L by nasal cannula to 15L high flow mask at 80% FiO2. The transfusion was stopped and a chest radiograph revealed diffuse parenchymal opacities with prominent interstitial markings and small bilateral pleural effusions suggestive if fluid overload / pulmonary edema. The patient then underwent gel foam uterine artery embolization by Interventional Radiology for definitive management.

On hospital day 2 the patient’s heart rate was 114 beats per minute and Hb was 5.2 g/dL, prompting infusion of an additional 2 units of HBOC-201. Due to continued hypoxia and radiographic evidence of fluid overload, diuretic therapy was administered. Her oxygen requirement decreased to 5L by nasal cannula, however did not improve from there despite a negative fluid balance, so a CT scan of the chest was performed which revealed significant bilateral basal atelectasis. The patient’s oxygen requirement resolved with incentive spirometry. The Bakri vaginal balloon was removed and minimal bleeding was observed.

On hospital day 3 the patient’s blood pressure increased to 176/78 mmHg. This, in the setting of proteinuria, peripheral edema and elevated aspartate aminotransferase (AST) to 104 unit/L (6-58 Unit/L) raised a suspicion for post-partum preeclampsia with severe features. Intravenous magnesium sulfate was briefly initiated for seizure prophylaxis, however it was discontinued after her blood pressure stabilized and the hypertension was attributed to a possible side effect of HBOC-201.

The patient received a total of 7.5 units of HBOC-201 over the course of 4 days in the MICU. Her troponin peaked on hospital day 2 at 2.930 ng/mL, and continued to downtrend with multiple infusions of HBOC-201. The patient’s own hematocrit began rising on hospital day 5 (Figure 2).

Figure 2.  Illustration of the hemoglobin and hematocrit over the course of the patient’s hospitalization and at her first out-patient follow up visit. The arrows indicate when HBOC-201 was infused.  Troponin I is also depicted on this graph to illustrate the resolution of severe end-organ damage due to the severe anemia.

The patient was transferred to the obstetrics floor on hospital day 7. In accordance with recent post-partum hemorrhage recommendations, she received 1025 mg of IV iron dextran. She was discharged home in stable condition on hospital day 8 with a Hb of 6.7 g/dL and Hct of 21%. Outpatient follow-up revealed significant improvement in anemia with a Hb of 9.2 g/dL and Hct of 30% one week after discharge.

Discussion

Acute post-partum hemorrhage leading to severe anemia remains the leading cause of maternal death worldwide (2). While the majority of post-partum hemorrhage leading to acute blood loss anemia is treated with transfusion of packed RBC or other blood products, there are certain subsets of patients who are unable to accept these products. This case demonstrates the use of a bovine hemoglobin-based oxygen carrier in a Jehovah’s Witness patient with severe post-partum hemorrhage who refused blood products. There have been multiple case reports regarding the use of HBOC-201 in severely anemic Jehovah’s Witness patients; however, there is no published report to our knowledge on the use of HBOC-201 in patients with symptomatic post-partum hemorrhage.

Hemoglobin-based oxygen carriers were developed in response to the infectious issues associated with donor RBC and in an attempt to come up with an alternative treatment in those situations where RBC transfusion was not an option. The first generation of these products was known to cause renal toxicity and coagulopathy (3,4). HBOC-201 is a second generation HBOC that is a cell-free, stroma-free, polymerized version of bovine hemoglobin. Because it contains no cell membrane, it is compatible with all blood types (no cross matching is needed).  The shelf life is 36 months at room temperature (5) (no refrigeration or sophisticated supply network is needed). A number of randomized control trials have been done to evaluate HBOC-201 (and other similar products) as a potential RBC replacement.  However, after infusion the short 24-hour half-life and statistical increase in adverse events associated with administration made it apparent that these HBOCs were not interchangeable with RBC for routine transfusion. While they are not interchangeable, many clinicians feel that the risk-benefit profile is favorable in severely anemic patients who cannot receive RBC. HBOC-201 is not yet approved for use in the United States, and therefore cannot be used outside of clinical trials. Several compassionate use studies are available in the United States to treat patients with life-threatening anemia when no other treatment option is available. Worldwide only a few countries have approved the use of HBOC-201 (6).

The side effect profile of the second generation HBOC’s is much preferable to that of the first (4). Reported class effects of HBOC use include hypertension, esophageal dysmotility and increased risk for myocardial infarction, all of which are related to vasoconstriction secondary to increased nitric oxide scavenging in these products (5). HBOC-201 in particular, has not been reported to increase risk of myocardial infarction. Rather, it has been reported that HBOC-201 reduces cardiac hypoxia in the setting of severe anemia (7). Mongan et al. (8) found that, while HBOC-201 causes transient systemic and pulmonary hypertension in swine, blood flow to 8 major organs, including the heart, was unchanged compared to controls. Serruys et al. (9) found no significant change in coronary blood flow and no vasoconstriction in humans pre-oxygenated with HBOC-201 prior to Percutaneous Coronary Intervention for coronary artery disease. In this case, the patient presented with troponinemia, indicating type 2 demand ischemia in the setting of severe anemia. Troponin levels began to down-trend after HBOC-201 infusion.

Common side effects of HBOC-201 in particular include transient hypertension, abdominal complaints, jaundice, elevated liver and pancreatic enzymes (10) and bovine methemoglobinemia (11). To prevent the increased oxidation of infused HBOC-201 to methemoglobin, ascorbic acid is co-administered; methemoglobin levels should be monitored and treated with methylene blue should they become significantly elevated (5).

This patient did experience increased hypoxia while receiving a unit of HBOC-201 which resulted in concern for transfusion reaction and transient discontinuation of the HBOC-201 infusion. It must be noted that HBOC-201 contains no cellular or plasma components, thus many transfusion reactions such as Transfusion Related Acute Lung Injury (TRALI) are an impossibility. HBOC-201 has been associated with volume overload; as it is a colloid this is a known complication (12). Volume overload was suspected, however, the patient did not improve with diuresis, and a chest CT revealed profound atelectasis. Given that her hypoxia greatly improved with incentive spirometry and ambulation, this was deemed unlikely to be a reaction associated with HBOC-201, but rather related to being bed-bound and critically ill.

One unit of HBOC-201 will raise serum Hb from 0.5g/dL to 2g/dL (12). One to two units of HBOC-201 are typically given for Hb levels <6 g/Dl, with additional units provided to maintain a goal Hemoglobin greater than 6g/dL (11, 12). With a half-life of 19-24 hours (5, 13), HBOC-201 must be infused regularly until the patient’s bone marrow production of RBC is sufficient, as evidenced by increases in hematocrit. It should be noted that HBOC-201 will only increase serum hemoglobin and not hematocrit; an initial decrease in hematocrit may be seen after infusion secondary to hemodilution (12).

The patient presented above experienced both transient hypertension and an increase in her serum AST, raising concern for post-partum preeclampsia. She was started on treatment for severe preeclampsia, however these affects were later attributed to the HBOC-201.

HBOC-201 is currently not recommended during pregnancy. One animal study in rats indicated that HBOC-201 infusion during organogenesis resulted in decreased litter size and increased incidence of external fetal malformations. This was thought to be related to decreased function of an inverted yolk sac, the primary nutritive organ for rat pups in utero (14). Holson et al. (15) performed a similar study on dogs which did not reveal a statistically significant difference in fetal malformations or other study end-points when compared to control. Canines and humans do not have an inverted yolk sac. Thus, it has been hypothesized that teratogenic effects of HBOC-201 do not apply to humans, however, more studies are needed. At least one US expanded access study allows pregnant women with the potential of massive blood loss (e.g. those with placenta accreta, placenta percreta) to consent to the study while still pregnant. However, HBOC-201 cannot be given until after delivery.

HBOC-201 in this case was utilized as a means to reverse severe end-organ damage due to anemia. This Jehovah’s Witness patient refused blood products, citing religious beliefs. Jehovah’s Witnesses in general will not receive “primary” blood components which include red blood cells, platelets and plasma. Other components, including albumin, clotting factors and HBOCs are considered “conscience items” through the church, where-in the individual can decide for themselves if they wish to receive them (5). With an estimated 1.2 million Jehovah’s Witnesses in the United States alone, alternative treatment options for this patient population are imperative (5).

While transfusion of allogeneic blood products remains the standard of care for treatment of severe post-partum hemorrhage, there are certain situations where this is not available. These might include lack of resources in a rural setting, blood product shortages, and inability to cross-match blood products given patient antibodies or patient denial of blood products due to personal or religious beliefs. HBOC’s are currently not approved for use in the United States, however they can be used on a limited compassionate use basis with FDA IND and local IRB approval, either as part of a planned expanded use study or on an emergency approval basis. Referral to a center with an expanded use protocol should be considered for a woman with the potential for massive bleeding who cannot receive RBC.

References

1. Enakpene CA, Morhason-Bello IO, Enakpene EO, Arowojolu AO, Omigbodun AO. Oral misoprostol for the prevention of primary post-partum hemorrhage during third stage of labor. J Obstet Gynaecol Res. 2007 Dec;33(6):810-7. [CrossRef] [PubMed]
2. Say L, Chou D, Gemmill A, Tunçalp Ö, Moller AB, Daniels J, et al. Global causes of maternal death: a WHO systematic analysis. Lancet Glob Health. 2014 2(6):e323–e333.[CrossRef] [PubMed]
3. Creteur J, Vincent JL. Hemoglobin solutions. Crit Care Med. 2003 Dec;31(12 Suppl):S698-707. [CrossRef] [PubMed]
4. Marinaro J, Smith J, Tawil I, Billstrand M, Crookston KP. HBOC-201 use in traumatic brain injury: case report and review of literature. Transfusion. 2009 Oct;49(10):2054-9. [CrossRef] [PubMed]
5. Epperla N, Strouse C, VanSandt AM, Foy P. Difficult to swallow: warm autoimmune hemolytic anemia in a Jehovah's Witness treated with hemoglobin concentrate complicated by achalasia. Transfusion. 2016 Jul;56(7):1801-6. [CrossRef] [PubMed]
6. Greenburg AG, Kim HW. Hemoglobin-based oxygen carriers. Crit Care. 2004;8 Suppl 2:S61-4. [CrossRef] [PubMed]
7. Fitzgerald MC, Chan JY, Ross AW, Liew SM, Butt WW, Baguley D, et al. A synthetic haemoglobin-based oxygen carrier and the reversal of cardiac hypoxia secondary to severe anaemia following trauma. Med J Aust. 2011 May;194(9):471-3. [PubMed]
8. Mongan PD, Moon-Massat PF, Rentko V, Mihok S, Dragovich A, Sharma P. Regional blood flow after serial normovolemic exchange transfusion with HBOC-201 (Hemopure®) in anesthetized swine. J Trauma. 2009 Jul;67(1):51-60. [CrossRef] [PubMed]
9. Serruys PW, Vranckx P, Slagboom T, Regar E, Meliga E, de Winter RJ, et al. Haemodynamic effects, safety, and tolerability of haemoglobin-based oxygen carrier-201 in patients undergoing PCI for CAD. EuroIntervention. 2008 Mar;3(5):600-9. [CrossRef] [PubMed]
10. Van Hemelrijck J, Levien LJ, Veeckman L, Pitman A, Zafirelis Z, Standl T. A safety and efficacy evaluation of hemoglobin-based oxygen carrier HBOC-201 in a randomized, multicenter red blood cell controlled trial in noncardiac surgery patients. Anesth Analg. 2014 Oct;119(4):766-76. [CrossRef] [PubMed]
11. Jordan SD, Alexander E. Bovine hemoglobin: a nontraditional approach to the management of acute anemia in a Jehovah's Witness patient with autoimmune hemolytic anemia. J Pharm Pract. 2013 Jun;26(3):257-60. [CrossRef] [PubMed]
12. Mer M, Hodgson E, Wallis L, Jacobson B, Levien L, Snyman J, et al. Hemoglobin glutamer-250 (bovine) in South Africa: consensus usage guidelines from clinician experts who have treated patients. Transfusion. 2016 Sep. [CrossRef] [PubMed]
13. Donahue LL, Shapira I, Shander A, Kolitz J, Allen S, Greenburg G. Management of acute anemia in a Jehovah's Witness patient with acute lymphoblastic leukemia with polymerized bovine hemoglobin-based oxygen carrier: a case report and review of literature. Transfusion. 2010 Jul;50(7):1561-7. [CrossRef]  [PubMed]
14. Stump DG, Holson JF, Harris C, Pearce LB, Watson RE, DeSesso JM. Developmental toxicity in rats of a hemoglobin-based oxygen carrier results from impeded function of the inverted visceral yolk sac. Reprod Toxicol. 2015 Apr;52:108-17. [CrossRef] [PubMed]
15. Holson JF, Stump DG, Pearce LB, Watson RE, DeSesso JM. Absence of developmental toxicity in a canine model after infusion of a hemoglobin-based oxygen carrier: Implications for risk assessment. Reprod Toxicol. 2015 Apr;52:101-7. [CrossRef] [PubMed] 

Cite as: Mytinger A, Sheehan E, Blue N, Crookston KP, Saeed AI. Management of life threatening post-partum hemorrhage with HBOC-201 in a Jehovah’s witness. Southwest J Pulm Crit Care. 2017;14(4):177-84. doi: https://doi.org/10.13175/swjpcc031-17 PDF

Tracheal Stoma Necrosis: A Case Report

Stella Pak, MD

Arjan Flora, MD 

Young-Sook Yoon, MD

Department of Medicine

University of Toledo Medical Center

Toledo, OH, USA

Abstract

Acute tracheal dilatation, due to an overinflated cuff, has been reported early in the course of mechanical ventilation through an endotracheal tube. Tracheal stoma necrosis is a rare complication, but such can accompany acute tracheal dilation. Herein, we report a case of tracheal necrosis 9 days following tracheostomy placement in a 71-year old woman associated with overinflation of the tracheal tube cuff. This case report aims to 1) add to the scant body of knowledge about the diagnosis and management for the patients with tracheal stoma necrosis and 2) raise awareness for error-traps in interpreting diagnostic images, specifically satisfaction of search error, inattentional blindness error, and alliterative error.

Case Report

A 71-year-old woman with a history of chronic respiratory failure on mechanical ventilation presented to the emergency department for bleeding around the tracheostomy site. The tracheostomy was recently inserted 9 days prior to admission. A chest radiograph demonstrated left lower lobe atelectasis, pleural effusion, and cardiomegaly that was consistent with pre-existing congestive heart failure (Figure 1).

Figure 1. Chest radiograph (AP) performed during first admission.

The cuff overinflation was demonstrated as a spherical shaped hypolucent region surrounding the trachea. However, the lesion escaped attention possibly because the focus of attention was limited to the thoracic compartment. A CT of the soft tissue in the neck ruled out the possibility of hematoma or infection. However, the features suggestive of overinflation of tracheostomy tube once again escaped attention. The spherical shaped hypolucent area, representing the cuff, was 3.9 cm in the anterior-posterior axis and 3.8 cm along the right-left axis.

A fiberoptic bronchoscopy through the tracheostomy tube revealed a large blood clot obstructing the distal end of the tube. A necrotic lesion around the stoma was also found. Careful observation via the bronchoscope during the procedure revealed no tearing or rupture. The patient was conservatively treated with vancomycin and cefepime for treatment of a ventilator-associated pneumonia. The oozing of blood from the tracheostomy stopped on with conservative wound care, including cleaning and dressing. She returned back to her baseline and was subsequently discharged on 3^rd day of admission. During this first admission, a tracheostomy tube exchange was not done due to bleeding from the stoma.

The patient was readmitted 12 days after discharge for an episode of hematemesis of approximately 400 mL of bright red blood. A chest radiograph showed satisfactory position of tracheotomy tube and cardiomegaly at baseline (Figure 2).

Figure 2.  Chest radiograph (AP) after readmission.

For the third time, the features suggestive of cuff-overinflation went unnoticed, delaying accurate diagnosis and proper treatment.

As a part of the patient’s evaluation, a CT of the chest with intravenous contrast was done, revealing the overinflated cuff of the trachea tube into the soft tissue of the neck (Figure 3).

Figure 3. Thoracic CT scan showing the overinflated tracheostomy cuff in the (A) coronal, (B) sagittal, and (C) axial views.

The ovoid shaped hypolucent area, representing the cuff, was 5.3 cm in the anterior-posterior axis and 4.6 cm along the right-left axis.

The Shiley proximal tracheal tube was urgently replaced with a portex Bivona tracheal tube. The new tracheostomy tube is more extensible, soft, and longer in distal length. Postoperatively, the patient was kept ventilated in the ICU. Repeated chest CT showed the new tracheostomy tube in satisfactory position and normalization of trachea shape. She made an uneventful recovery and was discharged 8 days after the tracheotomy tube replacement.

Discussion

A case of nonfatal hemorrhage due to innominate artery erosion with soft tissue necrosis at the stoma site of a tracheostomy is presented. In this ventilator-dependent patient with a recent tracheotomy stoma creation, an overinflated cuff of a tracheotomy tube was the key culprit in the pathology. Tracheal tube cuff pressure should be monitored so that it does not exceed a reasonable estimate of capillary perfusion pressure. Cuffs with pressure over 25 mmHg can compress the surrounding soft tissue, including delicate vascular structures. The damage to the vasculature in contact with the tube can result in ischemic necrosis in the soft tissue. If left untreated, these necrotic regions can develop infection or undergo fibrosis, leading to progressive stenosis (1).

A number of cognitive errors led to multiple episodes of misdiagnosis in this patient. Satisfaction of search error is a type of false negative error caused by premature termination of search after an abnormality has been detected (2). In this patient, we readily detected several abnormalities—cardiomegaly, pulmonary atelectasis, and pleural effusion. These initial findings likely led us to subconsciously neglect later findings.

Inattentional blindness error is a false negative error caused by the psychological lack of attention on an unexpected stimulus (3). In the present case, none of the diagnostic imaging was taken to check for cuff-overinflation. The images from the first admission were ordered for a concern of NG tube malposition, infection, and hematoma. The images ordered during the second admission were ordered to check the tracheotomy tube position. The thoracic compartment (the area for the expected abnormalities) received a disproportionately large amount of attention, whereas only a scant amount of attention was paid to the neck compartment.

Alliterative error is an error caused by a preconceived notion from a previous interpretation by a colleague or oneself (4). The negative finding in the previous reports could have affected the subsequent interpretative performance.

To the best of our knowledge, there are only 3 other cases of soft tissue necrosis caused by cuff overinflation. In two of these cases, the extended trachea did not recoil back to the previous size (5, 6). In the presented case, the stretched trachea recoiled back, similar to the case described by Sachdeva and his colleagues (7). The prognostic value of this difference in recovery is unknown, but might have a significant clinical implication. To explore the clinical relevance of this finding, more data on this condition is needed.

Teaching Points

1. Careful attention should be paid to cuff inflation pressure in patients presenting with bleeding at the tracheostomy site.
2. Conscious efforts to avoid well-known errors in diagnostic image interpretation, such as satisfaction of search error, and inattentional blindness error, should be made to improve diagnostic accuracy.

References

1. De Leyn P, Bedert L, Delcroix M, et al. Tracheotomy: clinical review and guidelines. Eur J Cardiothorac Surg. 2007 Sep;32(3):412-21. [CrossRef] [PubMed]
2. Ashman CJ, Yu JS, Wolfman D. Satisfaction of search in osteoradiology. AJR Am J Roentgenol. 2000 Aug;175(2):541-4. [CrossRef] [PubMed]
3. Richards A, Hannon EM, Derakshan N. Predicting and manipulating the incidence of inattentional blindness. Psychol Res. 2010 Nov;74(6):513-23. [CrossRef] [PubMed]
4. Berlin L. Malpractice issues in radiology. Alliterative errors. AJR Am J Roentgenol. 2000 Apr;174(4):925-31. [CrossRef] [PubMed]
5. Rhodes A, Lamb FJ, Grounds RM, Bennett ED. Tracheal dilatation complicating tracheal intubation. Anaesthesia. 1997 Jan;52(1):70-2. [CrossRef] [PubMed]
6. Honig EG, Francis PB. Persistent tracheal dilatation: onset after brief mechanical ventilation with a "soft-cuff" endotracheal tube. South Med J. 1979 Apr;72(4):487-90. [CrossRef] [PubMed]
7. Sachdeva A, Pickering EM, Reed RM, Shanholtz CB. Ice cream cone sign: reversible ballooning of the trachea due to tracheostomy tube cuff overinflation. BMJ Case Rep. 2016 May 4;2016. [CrossRef] [PubMed]

Cite as: Pak S, Flora A, Yoon Y-S. Tracheal stoma necrosis: a case report. Southwest J Pulm Crit Care. 2017;14(4):172-6. doi: https://doi.org/10.13175/swjpcc032-17 PDF 

June 2016 Critical Care Case of the Month

Theodore Loftsgard APRN, ACNP

Julia Terk PA-C

Lauren Trapp PA-C

Bhargavi Gali MD

Department of Anesthesiology

Mayo Clinic Minnesota

Rochester, MN USA

Critical Care Case of the Month CME Information

Members of the Arizona, New Mexico, Colorado and California Thoracic Societies and the Mayo Clinic are able to receive 0.25 AMA PRA Category 1 Credits™ for each case they complete. Completion of an evaluation form is required to receive credit and a link is provided on the last panel of the activity. 

0.25 AMA PRA Category 1 Credit(s)™

Estimated time to complete this activity: 0.25 hours 

Lead Author(s): Theodore Loftsgard, APRN, ACNP.  All Faculty, CME Planning Committee Members, and the CME Office Reviewers have disclosed that they do not have any relevant financial relationships with commercial interests that would constitute a conflict of interest concerning this CME activity.

Learning Objectives:
As a result of this activity I will be better able to:

1. Correctly interpret and identify clinical practices supported by the highest quality available evidence.
2. Will be better able to establsh the optimal evaluation leading to a correct diagnosis for patients with pulmonary, critical care and sleep disorders.
3. Will improve the translation of the most current clinical information into the delivery of high quality care for patients.
4. Will integrate new treatment options in discussing available treatment alternatives for patients with pulmonary, critical care and sleep related disorders.

Learning Format: Case-based, interactive online course, including mandatory assessment questions (number of questions varies by case). Please also read the Technical Requirements.

CME Sponsor: University of Arizona College of Medicine

Current Approval Period: January 1, 2015-December 31, 2016

Financial Support Received: None

History of Present Illness

A 64-year-old man underwent three vessel coronary artery bypass grafting (CABG). His intraoperative and postoperative course was remarkable other than transient atrial fibrillation postoperatively for which he was anticoagulated and incisional chest pain which was treated with ibuprofen. He was discharged on post-operative day 5. However, he presented to an outside emergency department two days later with chest pain which had been present since discharge but had intensified.

PMH, SH, and FH

He had the following past medical problems noted:

• Coronary artery disease
• Coronary artery aneurysm and thrombus of the left circumflex artery
• Dyslipidemia
• Hypertension
• Obstructive sleep apnea, on CPAP
• Prostate cancer, status post radical prostatectomy penile prosthesis

He had been a heavy cigarette smoker but had recently quit. Family history was noncontributory.

Physical Examination

His physical examination was unremarkable at that time other than changes consistent with his recent CABG.

Which of the following are appropriate at this time? (Click on the correct answer to proceed to the second of four panels)

1. Chest x-ray
2. Electrocardiogram (ECG)
3. Troponins
4. 1 and 3
5. All of the above

Cite as: Loftsgard T, Terk J, Trapp L, Gali B. June 2016 critical care case of the month. Southwest J Pulm Criti Care. 2016 Jun:12(6):212-5. doi: http://dx.doi.org/10.13175/swjpcc043-16 PDF