Top 10 Ambu Bag Tips Every Medical Student Must Know

 

Ambu (Bag-Valve-Mask) 

---

What is an Ambu bag (BVM)?
A Bag-Valve-Mask device is a handheld self-inflating bag attached to a face mask (and optionally an oxygen reservoir) that provides positive pressure ventilation to a patient who is apnoeic or hypoventilating. It's a lifesaving, first-line tool in resuscitation, emergency rooms, wards and prehospital care.

---

Why learn the Ambu bag well?

• It’s used in cardiac arrest, respiratory failure, during induction for airway control, and while awaiting definitive airway placement.

• Mistakes (too fast, too big breaths, poor seal) cause hypoxia, gastric insufflation, aspiration, or lung injury.

• Mastery improves patient outcomes and exam confidence.

---

Core components (visual checklist)

• Self-inflating bag (varied sizes: adult/child/infant)

• One-way valve / non-rebreathing valve

• Mask (anatomical masks in several sizes)

• Oxygen reservoir and inlet (for high FiO₂)

• PEEP valve (optional; helps oxygenation)

• Pressure relief valve (some models)
  (Tip: color-code or label masks by size in your skills lab.)

---

Types & sizes — quick facts

• Self-inflating BVM (most common; works without external gas flow)

• Flow-inflating bag (used in anaesthesia; requires gas flow)

• Sizes: Neonate (150–240 mL), Infant (240–500 mL), Child (500–700 mL), Adult (1000–1600 mL) — choose size that allows adequate but not excessive chest rise. (Life in the Fast Lane • LITFL)

---

Indications

• Respiratory arrest or severe respiratory depression

• Inadequate ventilation after airway obstruction relieved

• During CPR until advanced airway placed

• Short-term ventilation during airway management (intubation, suctioning)

Relative contraindication / caution

• Full stomach (high aspiration risk) — use rapid sequence and definitive airway if possible

• Poor mask fit (facial trauma) — consider supraglottic airway or early intubation

---

Pre-use check (quick mnemonic: “BAG-SAFE”)

• Bag integrity — no tears, reexpands after compression

• Attachments present (mask, reservoir, valve)

• Gas/oxygen inlet open (if using O₂)

• Size selected (mask + bag)

• Airway adjuncts ready (OPA/NPA, suction)

• Filters/PEEP in place if needed

• Equipment tested with visible chest rise on a test lung or assistant.

---

Ventilation targets (evidence-based):

• Adults (with a perfusing rhythm / not during CPR with advanced airway): 10–12 breaths/min (≈1 every 5–6 s). Aim for tidal volume ≈ 6–7 mL/kg ideal body weight (usually ~500–600 mL; squeeze until visible chest rise). (NCBI)

• During CPR (adult with advanced airway): 8–10 breaths/min (avoid hyperventilation). (Merck Manuals)

• Infants & children (rescue breathing / CPR with advanced airway): updated guidance recommends ~20–30 breaths/min (about 1 breath every 2–3 s) for infants/children in many resuscitation scenarios — but always follow local PALS/NLS protocols. (cpr.heart.org)

Big clinical rule: deliver only the volume needed to produce a gentle visible chest rise — not full hard compressions of the bag. Over-ventilation causes poor outcomes.

---

Step-by-step BVM ventilation — one-person technique (adult)

1. Position: supine, sniffing position (if no spinal injury).

2. Open airway: head-tilt–chin-lift (or jaw-thrust if suspected C-spine injury).

3. Mask placement: place mask over nose & mouth, index finger + thumb form a C across mask top; other three fingers pull the mandible upward (E-C technique).

4. Seal: press the mask downward at the bridge of the nose and along the jaw to create a tight seal.

5. Squeeze: compress bag smoothly until you see chest rise; release to allow full re-expansion. Rate ~10–12/min for adults. (NCBI)

Two-person technique (preferred when possible):

• One operator holds a two-handed seal on the mask (both hands forming two Cs/E-C grip, thumbs pressing), while the second squeezes the bag delivering controlled breaths. This gives a better seal and less gastric insufflation.

---

Child & infant technique — key differences

• Choose appropriately sized mask and bag (smaller volume).

• Use gentler squeeze and smaller tidal volume: aim 4–8 mL/kg depending on age and condition; watch chest rise carefully. (PMC)

• Ventilation rate: infants/children who are breathing inadequately or receiving rescue breaths: target ≈20–30/min per recent pediatric guidance. (cpr.heart.org)

---

Common mistakes (and how to avoid them)

• Hyperventilation (too fast/large breaths) → avoid by counting seconds between breaths and using a metronome or team leader cues. (PMC)

• Poor mask seal → two-person technique, head position, or airway adjuncts (OPA/NPA).

• Gastric insufflation → reduce tidal volume and inflation pressure, ensure correct rate, consider nasogastric decompression if needed.

• Wrong bag size → use an infant bag for infants; adult bag can overdeliver volume. (Life in the Fast Lane • LITFL)

---

Troubleshooting checklist (fast read)

• No chest rise → open airway (jaw thrust), check mask seal, check for obstruction, suction, change mask size.

• High resistance → bronchospasm, secretions, kinked tubing; consider suction, bronchodilator, or advanced airway.

• Low oxygen despite good technique → attach oxygen reservoir/flow to 10–15 L/min, add PEEP if tolerated. (Merck Manuals)

---

Complications

• Gastric insufflation → vomiting/aspiration

• Barotrauma / volutrauma (if volumes/pressures excessive)

• Hypoventilation/hyperventilation leading to CO₂ derangements

• Facial trauma from poor technique
  (Always escalate to advanced airway if prolonged ventilation needed.)

---

Cleaning, storage & maintenance

• Follow manufacturer guidance: disposable vs reusable parts.

• Reusable masks/bags: clean and disinfect per local policy; check valves for debris and function.

• Store with masks organized by size, oxygen tubing coiled, and test each bag periodically.

---

Exam tip: quick-memorize card (copy into your pocket)

• Adult breaths: 10–12/min. (NCBI)

• CPR advanced airway: 8–10/min. (Merck Manuals)

• Child/infant: ~20–30/min for rescue breathing/advanced airway scenarios — watch guidelines. (cpr.heart.org)

• Tidal volume: ~6–7 mL/kg (adult ≈500–600 mL) — stop at visible chest rise. (PMC)

---

Quick reference table

Patient	Rate (breaths/min)	Tidal volume guideline
Adult (perfusion, not CPR)	10–12	~6–7 mL/kg (~500–600 mL) (NCBI)
Adult (CPR, advanced airway)	8–10	Same target — avoid hyperventilation. (Merck Manuals)
Child / infant	~20–30 (PALS updates)	~4–8 mL/kg (age dependent) (cpr.heart.org)

---

Ready-to-use infographic/photo design (copy + paste for your blog)

Layout (vertical poster, portrait 1080×1920 or blog featured image 1200×628):

Top banner: Title — Ambu Bag (BVM) — Quick Life-Saving Steps (big, bold)

Section 1 — Visual: labeled photo of BVM parts (bag, one-way valve, mask, reservoir, PEEP)

• Use arrows + short labels (e.g., “O₂ inlet — attach to 10–15 L/min”, “One-way valve — prevents rebreathing”)

Section 2 — “Pre-use check” (icon checklist) — BAG-SAFE mnemonic (each with small icon)

Section 3 — Step-by-step: two columns (Left: One-person technique illustrated; Right: Two-person technique illustrated)

• Show hand positions (E-C), head tilt vs jaw thrust icon, visible chest rise arrow

Section 4 — Quick numbers (colored blocks): Adult 10–12 / CPR 8–10 / Child 20–30 / Tidal vol ~6–7 mL/kg

Section 5 — Troubleshooting icons (no chest rise, gastric insufflation, poor seal) with one-line fixes

Footer: Short reminder: “Deliver only enough to see chest rise. Avoid fast/forceful squeezes.” Add small citation line: “Sources: AHA 2020, StatPearls, Merck Manual.” (You can link in the article.)

---

Clinical pearls (small but high yield)

• Use a two-person technique whenever possible — it dramatically improves ventilation quality.

• Count out loud or use a metronome app to avoid hyperventilation.

• If oxygenation is poor despite good BVM technique, add PEEP, increase O₂ flow, and consider an advanced airway early. (Merck Manuals)