A Case of Oxygen Desaturation at POR

R1 Minghui Hung

Department of Anesthsiology, NTUH

Case Summary

61-year-old male DM and HTN under regular

medication control Smoking: 2 PPD for more than 40

years Alcohol: socially

Case Summary

Lower third esophageal cancer status post CCRT and transhiatal esophagectomy with gastric tube reconstruction and jejunostomy in April, 2000

Complicated with mild leakage at cervical anastomosis site.

Case Summary

Mild dysphagia when eating solid food

Recurrent pus discharge from left neck wound with local erythematous swelling

Ventral hernia and direct type inguinal hernia

Induction Course

Pre-induction SpO2: 97%

Induction with fentanyl (100μg),

thiopental (250mg),

succinylcholine (100mg),

atracurium (30mg),

adjuncts with Rubinol (0.3mg),

2% Xylocaine (100mg)

Induction Course

Endotracheal intubation was performed with laryngoscope.

Direct visualization of oropharyngeal secretions around the glottis.

Peri-operative Course

Peri-operative course was uneventful except one episode of desaturation decreased to 95%.

Aminophylline 1 amp intravenous drip and Solu-medrol 2 vials was given.

Extubation after operation and sent to POR with Atrovent (1amp) and Bricanyl (1amp) inhalation.

At POR

Intra-operativeIVF: 1500ml; urine output: 900ml

Oxygen saturation decreased to 89-90% when arriving POR

Tachypnea and dyspnea with restless

Bilateral inspiratory rales and crackles was noted

No wheezing

At POR

Oxygen saturation decreased to 75%, Ambu bag was used and SpO2 return to around 90%

ABG showed no obvious acid-base disorder, nor electrolyte imbalance, but hypoxemia was noted

Arterial Blood Gas Analysis pH: 7.350 PCO2: 39.8 mmHg PO2: 53.3 mmHg Na: 141 mM, K: 3.8 mM,

Cl: 113 mM, Ca: 1.02 mM Glucose: 192 mg/dL Hb: 15.2 g/dL HCO3: 22.1 mM BE: -3.7 mM O2Sat: 85.6% Anion Gap: 10 Osmolarity: 282 mOsm

At POR

Demerol 25mg for analgesia Lasix 1 amp was used for diuresis Portable CxR Complete EKG

Chest X-ray

CxR at POR Previous CxR

Complete EKG

CK: 85 U/L CK/MB:8.9 U/L Troponin I: 0 ng/ml

At POR

Blood pressure dropped to 75/48 mmHg, Dopamine set 10 ml/hr was used and emergent intubation was performed at POR

Sent to ICU with stable vital signs

Intensive Care Unit

Transthoracic cardiography – good LV contractility– no RA or RV dilatation – hypovolemia

Intensive Care Unit

At ICU, empirical antibiotics• Cefmetazone 2vials q8h• Gentamicin 1vial q12h

Inotropic agents• Dopamine• Levophed

Fresh frozen plasm transfusion Inhalation brochodilators Mechanical ventilator support (PEEP)

Intensive Care Unit

Cardiac enzyme

CK CK/MB Troponin I

10/24 85.0 8.9 0

10/25 340.0 12.3 0

408.0 15.9 0

398.0 14.8 0

10/26 334.0 14.2 0

Intensive Care Unit

Hemogram

10/21 10/24 10/25 10/27

WBC 7640 8820 13960 7910

Hb 14.4 15.1 13.0 10.8

PLT 179K 177K 166K 137K

Intensive Care Unit

Coagulation study

10/21 10/24 10/25 10/28

PT 11.6/11.2 12.8/11.9 13.8/11.3 11.1/10.8

PTT 37.5/36.2 32.8/35.4 41.9/35.2 43.8/36.0

D-Dimer 1.76

Intensive Care Unit

Blood chemistry study

10/21 10/24 10/26 10/28

Alb 4.1 3.07 3.7

T-Bil 0.3 1.01 0.9

AST 21.0 20.0 23.0

BUN 13.9 10.4 23.8 12.3

CRE 0.7 0.68 0.64 0.6

Intensive Care Unit

Inotropic agents was titrated and DC at day 2

Ventilator weaning and extubation at day 3

No more dyspnea Bilateral rales and crackles impro

ved except RLL Back to general ward on day 5

What happened?→Pulmonary Edema

Hemodynamic edemaLV failure, mitral stenosisLeft-to-right cardiac shunt, fluid overload, severe anemia

Permeability edemaSepsis, trauma, pulmonary aspi

ration

Factors Predisposing to Aspiration Lower esophageal sphincter Upper esophageal sphincter Protective airway reflexes

• Apnea with laryngospasm• Coughing• Expiration• Spasmodic panting

Post-esophagectomy status

An oro-gastric connection with significantly compromised esophageal sphincter function

→increase risk of aspiration

Neck dissection and radiation therapy produce fibrotic change and distortion of neck anatomy

→difficult intubation

Pulmonary Aspiration

Aspiration pneumonitisChemical injury caused by the inhalation of the sterile gastric contents

Aspiration pneumoniaAn infectious process caused by the inhalation of oropharyngeal secretion

s that are colonized by pathogenic bacteria

Aspiration Pneumonitis

Severity associated with the volume and pH of aspirate, particulate food matters

Biphasic pattern of lung injuryPhase I: Direct injury of alveolar-

capillary interfacePhase II: Acute inflammation

Aspiration Pneumonitis

Syptoms and signsGastric material in the oropharynxWheezingCoughingShortness of breathCyanosisPulmonary edemaHypotensionHypoxemiaRapid progression to ARDS

Aspiration Pneumonia Diagnosis

a patient at risk for aspiration has radiographic evidence of an infiltrate in a characteristic bronchopulmonary segment

Risksstroke, neurologic dysphagia, disruption of the GE junction, anatomical abnormalities of the upper aerodigestive tract, elderly persons with poor oral care

What We Can Do to Prevent Aspiration Pre-anesthetic evaluation NPO policy Reducing gastric volume Cricoid pressure Airway device

In post-esophagectomy patient

Carefully evaluated prior to intubation

Consider intubated in an upright postion

Subject to a low clinical threshold to proceed to fiberoptic intubation in the sitting position.

The EndThank you