Perioperative Aspiration and Unexpected Death in the Operating Room

Perioperative Aspiration and Unexpected Death in the Operating Room 

Aspiration during surgery occurs approximately 1 in every 2000 to 3000 surgical procedures requiring anesthesia with half of those developing an aspiration-related lung injury, such as pneumonitis or aspiration pneumonia (Nason, 2015). The mortality rate as a result of aspiration is quite significant. Up to as much of 90% of patients diagnosed with aspiration pneumonia or pneumonitis will likely result in death (Nason, 2015). A thorough preoperative evaluation cannot foresee every potential aspiration case; therefore, anesthesia providers must prepare for the unexpected. Since aspiration is well-defined as the entry of liquid or solid material into the trachea and lungs, anesthesia-related aspiration occurs when patients lacking adequate laryngeal protective reflexes passively or actively regurgitate gastric contents (Nason, 2015).

Case Report #1

S. S. was a 72-year-old male. He was 66” and weighed 77.8kg. He presented to the emergency room (ER) with severe abdominal pain and vomited what was noted to be a small amount of black fluid. His health history included obstructive sleep apnea (OSA), hypothyroid, hyperlipidemia, gout, enlarged prostate, anxiety, and an acute abdomen. Emergency surgery was scheduled for an incarcerated right inguinal hernia repair, possible bowel resection, possible laparotomy. Upon arrival to the ER, the pt denied any solid food for six days prior to arrival due to complaints of generalized malaise and abdominal pain. Presenting vital signs (VS) showed systolic blood pressure of 60 mmHg with a heart rate in the 120s. The pt was placed in Trendelenburg with 2 liters fluid given. Systolic blood pressure increased to 100 mmHg. Placement of nasogastric tubes (NGT) were attempted twice, and both times removed by the pt with refusal for placement due to discomfort. The ER physician note stated that the “pt was high risk for aspiration, self-removed 2 NGTs, and does not want it replaced.” The pt arrived to the operating room (OR) holding area with VS of B/P=132/77 and HR=108. The pt stated he vomited small amts while in the ER but denied further complaints of nausea or vomiting. The anesthesiologist placed an arterial line in preop holding. He was then brought into the OR. A Glidescope #3 was ready for use. Lidocaine 100mg given. A rapid sequence induction (RSI) with cricoid pressure was initiated. Seconds later, an immediate return of dark green fluid erupted from the pt’s mouth. A suction yankauer was immediately placed in posterior oropharynx and an attempt to secure the airway with Glidescope was noted to be impossible due to the massive amount of gastric content erupting from the pharynx. The pt was placed in Trendelenburg and head turned toward the right side by the anesthesiologist. A second yankauer suction was also placed in the pharynx to attempt visualization of the vocal cords. A second attempt with the Glidescope partially revealed the superior portion of the vocal cords, and a #8.0 OET EVAC tube was quickly placed and cuff inflated. +ETCO2 was noted and cricoid pressure was released. The total gastric output was more than 3500mL. A central line was placed, and a pulmonologist was consulted for a bronchoscopy during surgery. The pulmonologist reported “patchy greenish secretions from both right and left bronchial trees were suctioned with an especially angry looking left bronchial tree”. After surgery, the pt was transferred to the intensive care unit. Portable CXRs showed a progressive whitening in bilateral lung fields, more notably on the left side. S.S.’s prognosis was discussed with family, and they elected to remove life support. The pt passed away.

Discussion

Pulmonary aspiration can lead to different levels of lung problems with the most common lung injury being aspiration pneumonitis, which could ultimately lead to cardiopulmonary collapse and death (Nason, 2015). There are many factors that affect the severity of the lung damage. It mainly depends on how much fluid is aspirated, the acidity of the fluid, and the presence or absence of particulate matter (Nason, 2015). The acidity of aspirated fluid seems to be a large determinant of lung recovery. For example, even a scant amount of fluid with a low gastric pH can cause death, whereas a high volume of fluid with a high pH might be tolerated better. According to Nason (2015), as much as 50 ml of aspirated gastric contents can be considered a severe aspiration. Considering the lung insult incurred by this pt, there was minimal chance for recovery. Although, the life-threatening amount of aspirate in humans is determined to be approximately 0.8mL/kg based on animal studies (Isono, Eikermann, & Odaka, 2014). More importantly, it is the overall clinical picture (volume and acidity of aspirate) that will affect survival. There are other influences besides those mentioned that increased the risk of aspiration in this pt. Intraluminal esophagus and intestinal pressures play a role in aspiration, as well as gastric contents in the system, anesthesia, and anesthesia-related drugs (Isono, Eikermann, & Odaka, 2014).

Some researchers suggest that having an NGT in place could be problematic. There is a chance that it could weaken the functional strength of the upper and lower esophageal sphincters, increase the number of lower esophageal relaxation periods, and decrease the upper airway reflexes, all while decreasing the pressure inside the stomach as well (Isono, Eikermann, & Odaka, 2014). This warrants further research because placing an NGT is a routine clinical anesthesia practice for acute abdominal cases to decompress the stomach of gastric contents.

The literature states that for a proper RSI, there needs to be consideration of preoxygenation, suction, specific induction drugs, identifying proper cricoid pressure, and minimize laryngoscopy attempts (Gebremedhn, Mesele, Aemero, & Alemu, 2014). One alternate consideration in the RSI sequence is the use of rocuronium instead of succinylcholine. Succinylcholine has been found to increase intra-abdominal pressure; therefore, a high dose of rocuronium could be used as an alternative (Koh, et al., 2018). Also, some medications used for induction can decrease lower esophageal sphincter tone, such as propofol, opioids, and anesthetic gases (Nason, 2015). Therefore, intubation should occur as rapidly as possible since the induction of anesthesia leads to an inability to protect airway reflexes.

In 1961, Dr. Brian Sellick encouraged the use of what he coined to be Sellick’s maneuver. This was “temporarily occluding the very proximal part of the esophagus by backward pressure on the cricoid cartilage against the cervical vertebrae”, which prevents fluid from entering the pharynx (Emergency Physicians Monthly, 2019). This became an important part of anesthesia when performing an RSI. Many years later, researchers began reviewing CT scans during application of cricoid pressure and found that the esophagus incurred a lateral displacement of the esophagus (Bhatia, Bhagat, & Sen, 2014). This has huge implications for anesthesia providers. Bhatia, Bhagat, & Sen (2014) found that applying cricoid pressure actually increased prevalence of lateral displacement of the esophagus from 53% to 91%. Further research is needed to determine the validity of this maneuver in present day anesthesia.

Although most anesthesia providers abstain from positive-pressure ventilation after RSI and before intubation, preparation for oxygenation in case of a failed intubation attempt should be in the backup plan since desaturation is likely to occur rather rapidly. Higher inspiratory pressures may be needed to achieve acceptable ventilatory volumes in patients with reduced lung compliance such as in obese patients or with increased intra-abdominal pressure (Isono, Eikermann, & Odaka, 2014). Using a two-hand technique during ventilation can improve air flow and eventually lung compliance as paralytics begin to take effect.

Summary Lesson

Quick decisions are made when a pt presents with an acute abdomen. In hindsight, despite research that suggests NGTs may pose a problem, I feel it would have made a positive difference in the outcome of this case. An NGT inserted before the OR and placed to suction, could have possibly revealed the impending catastrophe. Needless to say, cricoid pressure was no match for >3500mL of gastric contents. Another test missing from this case report was abdominal x-ray films. Perhaps this was overlooked since the pt did not present with a protuberant abdomen and the initial vomitus was a small amount. The action of placing the pt in trendelenburg position with the head turned remains unclear. The pt had an average body mass so I would have opted to turn the pt in a “sloppy” lateral position. I have previously intubated a pt in a “sloppy” lateral position using a Glidescope and is not technically challenging.

Unexpected Death in the Operating Room: Case Study #2

Globally, more than 300 million people have a surgical procedure every year (Gregory, et al., 2018). Despite efforts to improve outcomes, surgical morbidity and mortality still occurs in the operating room (OR). The percentage of patients who die during the perioperative period is known as the perioperative mortality rate (POMR) (Ariyaratnam, et al., 2015). Complications during surgery can occur for many reasons both known and unknown and why it is of utter importance to report such occurrenes. Emergency surgery, being elderly, and having any major surgery are all recorded to play a considerable part in surgical mortality (Heeney, Hand, Bates, McCormack, & Mealy, 2014).

Case Report #2

L.M. was a 70 year-old male. He was 64.5” tall and weighed 71kg. L.M. was scheduled for a transurethral resection of the prostate (TURP) on 01/29/2019. Significant health history included hypertension, atrial fibrillation (currently normal sinus rhythm), history of deep vein thrombosis, alcoholic cardiomyopathy in 2017, syncope with collapse, and prostate cancer. Lab values were relatively normal the day before surgery. Medications significant to this case include metoprolol and dabigatran. He discontinued the dabigatran after seeing the cardiologist on 01/23/2019. Baseline blood pressure (B/P) was 153/78 and heart rate (HR) of 72.

The pt was in relatively good condition, able to walk long distances without stopping and climb stairs without shortness of breath. L.M. He had a small pericardial effusion which was unchanged and had no impact on his activities. He had a previous anesthetic three weeks prior without any complications. L.M. was evaluated and cleared by the cardiologist with recommendations to stop dabigatran three days before surgery. The pt declined a spinal due to back pain. The pt given 2mg of versed, taken into the OR, and moved to the procedure table. A smooth induction with lidocaine and propofol initiated, easy insertion of a #4 laryngeal mask airway, and Sevoflurane started. The lower extremities were placed in a low lithotomy position.

Approximately one hour into surgery, the heart rhythm quickly progressed from sinus into a low rate type bradycardia. The surgeon was informed. The anesthetist administered glycopyrrolate; however, within one minute, the QRS became wider. The B/P cycled 3-4 times before finally reading 60 mmHg. Ephedrine 15mg given, anesthesiologist paged for assistance, and preparation was made to convert the airway to an ETT. An additional 100mg of succinylcholine was administered, and the pt was intubated. The B/P remained undetectable. Sevoflurane was turned off and the surgeon was directed to stop surgery, as well as irrigation fluid of normal saline (NS). Pulseless Electrical Activity was noted. CPR was initiated, and compressions were proven adequate when a blood gas revealed a pH of 7.29, pCO2 51, pO2 198, HCO3 25. The pt was given multiple rounds of epinephrine, atropine, levophed, and started on a levophed gtt, including Na HCO3, magnesium, and vasopressin. A pulse was shortly regained twice during the resuscitation process but never sustained. As a last ditch effort during the resuscitative process, the anesthesiologist ordered TPA be administered with no change in outcome. After 74 minutes of resuscitative measures, the pt was pronounced dead in the OR. Family refused an autopsy.

Discussion

TURP syndrome could be a cause of death in this pt, although his preoperative sodium level was relatively normal; besides, NS was the irrigating fluid utilized. There was no need to treat the pt with hypertonic saline. If an intraoperative BMP revealed a dilutional type of hyponatremia due to massive instillation of irrigating fluid, then hypertonic saline 3% could be an option. NS 3% is to be given in 100 ml boluses, which provides 51 mEq of sodium and increases sodium levels by 2–3 mEq/L (Emmett, Istre, & Hahn, 2018). The same authors also noted that these 100mL boluses be infused no faster than one bolus per hour. In addition to hyponatremia during this type of surgery, using an epidural/spinal combination anesthetic or a vagovasal reflex from bladder irrigation filling could also cause hypotension (Nakahira, Toshiyuki, Fujiwara, & Minami, 2014). Unfortunately, general anesthesia masked the signs and symptoms of a potential problem. The pt refused a spinal anesthetic.

Early signs and symptoms of TURP syndrome include nausea, malaise, headache, lethargy, obtundation, electrocardiogram waveform morphology changes, progressing to pulmonary edema, cerebral edema and cardiac collapse (Smith & Patel, 2011). Perhaps the height of the irrigation fluid was a contributing factor in this death. It is not a common practice for anesthesia providers to direct surgeons about proper surgical techniques. According to Smith & Patel (2011), the height of irrigation fluids, which affects the infusion pressures, should be minimized to reduce the potential for hyponatremia. Accounting for irrigation fluid bags is also essential. The best irrigating fluids for TURPs via bipolar cautery are NS and lactated ringers solutions. These solutions are isotonic, do not cause the breakdown of blood cells, compatible with body fluids, and excreted quickly, if absorbed (Smith & Patel, 2011).

Physiologic cardiac and neurological changes during this type of procedure should divert the focus from one of surgery completion to that of maintaining phyiologic balance, securing circulatory and ventilatory support, and aborting the surgery, if needed (Rosner and Tamara, 2012). Although the pt had a sinus rhythm, he was on dabigatran therapy for atrial fibrillation. The pt abstained from taking dabigatran three to four days more than recommended by the cardiologist. Ischemic stroke is the primary adverse health disorder as a result of atrial fibrillation (Kernan, et al., 2014). It was unknown if the pt suffered a major stroke during surgery — no information about a carotid duplex scan or coronary vessel status was documented.

It is difficult to find information on deaths that occur during surgery. The family’s refusal to perform an autopsy makes it tough to understand the catastrophic events that happened in the OR. Following the ACLS protocols and chest compressions is appropriate for any witnessed cardiac arrest. A designated recorder needs establishing at the beginning of the code. Advanced Cardiac Life Support (ACLS) protocols published by the American Heart Association are the standard of care for patients in cardiac arrest. While not applicable for this pt, studies reveal that good adherence to ACLS protocols is a determinant of return of spontaneous circulation (ROSC) (Lee, Huang, Lee, Hsu, & Su, 2018). Comments were made by multiple providers that the code was one of the most aggressive attempts performed in the history of their practice. The quality of compressions was based on the amount of blood pressure that was generated on the arterial line tracing. The main criticism of the code effort came from a cardiologist in regards to administering TPA as a last ditch effort without verifying an actual clot.

Conclusion

Although he presented with a few comorbidities, he was in generally good condition and quite active. Nothing about this patient was significant enough to postpone the procedure, although hindsight is always 20/20. It is uncertain if withholding the dabigatran for three extra days created an environment for clot formation. Perhaps an intraoperative BMP should have been drawn after a specific time frame of irrigational fluid administration. Standarding the way we report and analyze intraoperative deaths will strengthen the validity of POMR as the primary indicator of the safety and quality of surgery and anesthesia care. This case study was discussed at multiple M&M meetings.

References

• Ariyaratnam, R., Palmqvist, C. L., Hider, P., Laing, G. L., Stupart, D., Wilson, L., . . . Gruen, R. L. (2015). Toward a standard approach to measurement and reporting of perioperative mortality rate as a global indicator for surgery. Surgery, 158(1), 17-26. doi:10.1016/j.surg.2015.03.024
• Bhatia, N., Bhagat, H., & Sen, I. (2014). Cricoid pressure: Where do we stand? Journal of Anaesthesiology Clinical Pharmacology, 30(1), 3-6. doi:10.4103/0970-9185.125683
• Emergency Physicians Monthly. (2019). Where did Sellick’s Maneuver come from? Retrieved from Emergency Physicians Monthly: http://epmonthly.com/article/where-did-sellicks-maneuver-come-from/
• Emmett, M., Istre, O., & Hahn, R. G. (2018, September 20). Hyponatremia following transurethral resection or hysteroscopy. Retrieved from UpToDate: https://www.uptodate.com/contents/hyponatremia-following-transurethral-resection-or-hysteroscopy
• Gebremedhn, E. G., Mesele, D., Aemero, D., & Alemu, E. (2014). The incidence of oxygen desaturation during rapid sequence induction and intubation. World Journal of Emergency Medicine, 5(4), 279-285. doi:10.5847/wjem.j.issn.1920-8642.2014.04.007
• Gregory, S., Murray-Torres, T. M., Fritz, B. A., Abdallah, A. B., Helsten, D. L., Wildes, T. S., . . . Avidan, M. S. (2018). Study protocol for the Anesthesiology Control Tower—Feedback Alerts to Supplement Treatments (ACTFAST-3) trial: A pilot randomized controlled trial in intraoperative telemedicine. F1000 Research, 7(623). doi:10.12688/f1000research.14897.2
• Heeney, A., Hand, F., Bates, J., McCormack, O., & Mealy, K. (2014). Surgical mortality – An analysis of all deaths within a general surgical department. The Surgeon, 12(3), 121-128. doi:10.1016/j.surge.2013.07.005
• Isono, S., Eikermann, M., & Odaka, T. (2014). Facemask Ventilation during Induction of Anesthesia: How “Gentle” Is “Gentle” Enough? Anesthesiology, 120(2), 263-265. doi:10.1097/ALN.0000000000000095
• Kernan, W. N., Ovbiagele, B., Black, H. R., Bravata, D. M., Chimowitz, M. I., Ezekowitz, M. D., . . . Wilson, J. A. (2014). Guidelines for the prevention of stroke in patients with stroke and transient ischemic attack. Stroke, 45, 2160-2236. doi:10.1161/STR.0000000000000024
• Lee, C.-H., Huang, M.-Y., Lee, Y.-K., Hsu, C.-Y., & Su, Y.-C. (2018). Implementation of a real-time qualitative app to evaluate resuscitation performance in an Advanced Cardiac Life Support course. Tzu Chi Medical Journal, 30(3), 165-168. doi:10.4103/tcmj.tcmj_103_17
• McKechnie, S., & Walsh, T. (2018). Metabolic response to injury, fluid and electrolyte balance and shock. In O. J. Garden, & R. W. Parks, Principles and Practices of Surgery (7th ed., pp. 3-28). Elsevier. Retrieved from https://books.google.com/books?hl=en&lr=&id=msUmDwAAQBAJ&oi=fnd&pg=PP1&dq=administering+vasopressin+during+code+in+TURP&ots=OneLMP–Gi&sig=FKJ8U7LtlppFhR7Pxb3f-RNVnLA#v=onepage&q&f=false
• Nakahira, J., Toshiyuki, S., Fujiwara, A., & Minami, T. (2014). Transurethral resection syndrome in elderly patients: A retrospective observational study. BMC Anesthesiology, 14(30). doi:10.1186/1471-2253-14-30
• Nason, K. S. (2015). Acute intraoperative pulmonary aspiration. Thoracic Surgery Clinics, 25(3), 301-307. doi:10.1016/j.thorsurg.2015.04.011
• Smith, R. D., & Patel, A. (2011). Transurethral resection of the prostate revisited and updated. Current Opinion in Urology, 21(1), 36-41. doi:10.1097/MOU.0b013e3283411455