CHS Cheat Sheet 2026

The 30 highest-yield CHS facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. Which regulatory body's standards most directly govern medical record retention requirements for hyperbaric facilities in the US? → State health departments and CMS
2. A patient on dialysis has BP of 178/102 mmHg. Interdialytic weight gain is 4.5 kg. What is the primary mechanism driving hypertension in this patient? → Volume overload from sodium and fluid retention
3. A CHS is counseling a patient about the DASH diet. Which food swap best exemplifies applying DASH principles? → Replacing white bread with whole grain bread and adding a side of spinach
4. In the treatment of arterial gas embolism (AGE), what is the initial target pressure during HBO2 therapy? → 2.8–3.0 ATA
5. What should a clinician do when a difference of more than 10 mmHg is found between arms during the initial blood pressure assessment? → Use the higher reading and investigate for vascular disease
6. A patient reports taking disulfiram (Antabuse). This is relevant to HBO assessment because it: → Increases CNS oxygen toxicity risk
7. Per UHMS and CMS guidelines, at what point should HBO2 efficacy be formally reassessed in diabetic foot ulcer patients? → After 20–30 treatments
8. What is the primary hazard associated with cotton clothing in a hyperbaric oxygen environment? → Cotton is a fuel source that can ignite in an oxygen-enriched atmosphere
9. In a multiplace chamber fire, the most important initial step after alerting staff is to: → Emergency decompress and evacuate all occupants
10. What is a work breakdown structure in CHS practice? → Hierarchical decomposition of deliverables into manageable work packages
11. Which feature best distinguishes preeclampsia from chronic hypertension in a woman presenting with elevated BP at 24 weeks gestation? → New-onset proteinuria and elevated liver enzymes after 20 weeks
12. In the context of HBO therapy, what is the primary infection risk associated with using a hyperbaric oxygen hood that is not properly dried before storage? → Promotion of bacterial and fungal biofilm growth inside the hood
13. Carotid intima-media thickness (CIMT) measurement in hypertension is used primarily to: → Detect subclinical atherosclerosis and stratify cardiovascular risk
14. Which personal protective equipment (PPE) combination is correct when performing wound care on a hyperbaric patient with a heavily draining infected wound? → Gloves, gown, mask, and eye protection
15. A patient with a history of thoracic surgery requests HBO therapy. Which specific post-surgical concern is most relevant to hyperbaric safety? → Trapped gas in post-surgical spaces can expand during decompression causing barotrauma
16. What is the recommended maximum daily sodium intake for adults with hypertension according to the American Heart Association? → 1,500 mg
17. In CHS practice, what constitutes a conflict of interest? → When personal interests could compromise professional judgment
18. Which of the following best describes the ethical concept of 'non-maleficence' in hyperbaric medicine? → Avoiding actions that cause unnecessary harm to the patient
19. Which documentation element is MOST critical to include in a hyperbaric treatment record for patient safety and liability purposes? → Pre-treatment assessment findings, treatment parameters, and any adverse events
20. Which BP target is recommended by ACC/AHA 2017 guidelines for most adults aged ≥65 years with hypertension and high cardiovascular risk? → <130/80 mmHg
21. A patient with type 1 diabetes requires blood glucose monitoring during a 90-minute HBO treatment. The preferred method is: → Fingerstick glucose check via glucometer passed through the chamber medical lock
22. A patient scheduled for HBO therapy has active pulmonary tuberculosis (TB). What is the MOST appropriate precaution when treating this patient? → Airborne precautions including an N95 respirator for staff
23. What is the recommended maximum alcohol consumption per day for men with hypertension to reduce cardiovascular risk? → No more than 2 standard drinks
24. A patient refuses to remove a contraindicated item before entering the hyperbaric chamber despite being informed of the risk. What should the technologist do? → Document the refusal, notify the physician, and defer treatment until resolved
25. Reactive oxygen species (ROS) contribute to hypertension by which of the following mechanisms? → Scavenging nitric oxide to form peroxynitrite, reducing vasodilatory capacity
26. When a patient experiences claustrophobia during HBO treatment, the incident report should include: → Description of the episode, patient's response, interventions used, and outcome
27. What blood pressure reduction is typically expected from adopting the DASH diet alone in hypertensive individuals? → 8–14 mmHg systolic reduction
28. What baseline vital sign parameter is MOST important to document before each HBO treatment session for a patient with a recent stroke? → Blood pressure
29. A claustrophobic patient refuses to enter the monoplace chamber. After counseling, the most appropriate next step is to: → Attempt treatment in a multiplace chamber where available, with anxiolytic support
30. When advising hypertensive patients about dietary fat, which approach best aligns with cardiovascular risk reduction guidelines? → Reduce saturated and trans fats and replace with unsaturated fats