Complications After General Anesthesia and Physiotherapy Management

Part I: Complications After General Anesthesia

A. Respiratory Complications

• Most frequent postoperative pulmonary complication.
• GA causes loss of functional residual capacity (FRC), diaphragmatic dysfunction, and loss of sighing reflex, leading to alveolar collapse.
• GA reduces FRC by ~20% (400-500 mL) due to cephalad diaphragm shift under anesthesia (Miller's Anesthesia, 10th Ed.).
• Risk is highest after abdominal and thoracic surgeries.

• PPCs encompass pneumonia, ARDS, atelectasis, aspiration, and respiratory failure.
• Occur in ~5% of patients undergoing non-thoracic surgery (Miller's Anesthesia, 10th Ed.).
• Risk factors: advanced age, COPD, obesity (BMI >30), smoking, ASA class ≥2, poor nutritional status, long surgery duration, upper abdominal or thoracic procedures.

• Regurgitation and aspiration of gastric contents during induction or emergence.
• Can cause aspiration pneumonitis (chemical) or aspiration pneumonia (bacterial).
• Predisposed by: full stomach, hiatus hernia, delayed gastric emptying, emergency surgery.

• Laryngospasm: reflex closure of the vocal cords during light anesthesia or airway stimulation.
• Bronchospasm: reactive airway narrowing, more common in asthmatic or COPD patients.

• Due to ventilation-perfusion (V/Q) mismatch, hypoventilation, or diffusion impairment post-extubation.

• Incomplete reversal of neuromuscular blocking agents leads to respiratory muscle weakness, poor cough, and upper airway obstruction.

B. Cardiovascular Complications

• Most common hemodynamic complication during and after GA.
• Caused by myocardial depression, vasodilation (volatile agents), hypovolemia, or vasovagal responses.

• Post-operative hypertension from pain, anxiety, bladder distension, emergence agitation, or pre-existing hypertension.

• Sinus bradycardia (from opioids, neostigmine), tachycardia (from pain, hypovolemia), or more serious ventricular arrhythmias.
• Electrolyte disturbances (hypokalemia, hypomagnesemia) are contributing factors.

• Perioperative myocardial infarction in high-risk patients.
• Occurs especially in patients with coronary artery disease undergoing major surgery.

C. Neurological Complications

• One of the most common and distressing complications (~30% incidence).
• Triggered by volatile agents, opioids, N2O, female sex, non-smoker status, history of motion sickness.

• Overdose of anesthetic agents, hypothermia, or residual opioid/benzodiazepine effect.

• Common in children and elderly; manifests as disorientation, combativeness, and distress.
• Risk factors: rapid emergence from volatile agents (especially desflurane), pain, anxiety.

• Subtle cognitive impairment lasting days to weeks post-GA, especially in elderly patients.

• Caused by improper positioning on the operating table (e.g., brachial plexus stretch, common peroneal nerve compression).

D. Thermoregulatory Complications

• GA impairs thermoregulation; core temperature falls by 1-2°C intraoperatively.
• Causes: shivering, increased oxygen consumption, coagulopathy, delayed drug metabolism.

• Rare but life-threatening hypermetabolic crisis triggered by volatile agents or succinylcholine.
• Genetic predisposition (ryanodine receptor mutation).

E. Other Complications

• From endotracheal intubation or LMA insertion causing mucosal trauma.

• During laryngoscopy and intubation.

• Especially after spinal/epidural analgesia or pelvic surgery under GA.

Part II: Physiotherapy Management of Post-GA Complications

1. Physiotherapy for Atelectasis and Respiratory Complications

a) Breathing Exercises

• Deep Breathing Exercises (DBE): Slow, maximal inspiratory effort to increase tidal volume and reopen collapsed alveoli. 10-15 repetitions every 2 hours while awake.
• Diaphragmatic Breathing: Encourages use of the primary inspiratory muscle, especially important post-abdominal or thoracic surgery where splinting prevents deep breathing.
• Incentive Spirometry: Patient takes a slow, sustained maximal inspiration with visual feedback from a flow-based device. Promotes uniform alveolar expansion and improves inspiratory muscle recruitment. Target: 10 breaths/hour while awake.
• Segmental (Localised) Breathing: Therapist places hands over specific lung segments to encourage regional ventilation. Useful for localized atelectasis.

b) Airway Clearance Techniques (ACT)

• Huffing (Forced Expiratory Technique - FET): A series of huffs (glottis-open forced expirations) followed by relaxed breathing. Mobilizes secretions from medium to large airways efficiently without raising intrathoracic pressure as much as coughing.
• Controlled Coughing: After adequate pain control (splinting the incision with a pillow), patients are instructed to take 2-3 deep breaths and then cough forcefully on the third expiration.
• Active Cycle of Breathing Technique (ACBT): Cycles of breathing control (diaphragmatic breathing) + thoracic expansion exercises + FET. Most evidence-based ACT for post-surgical patients.
• Postural Drainage: Positioning the patient to use gravity to drain secretions from specific lung segments. Combined with percussion and vibration for maximum effect.
• Manual Techniques: Chest percussion (clapping), vibrations, and shaking applied during expiration to dislodge secretions. Note: avoid over incision sites, osteoporotic ribs, or fresh CABG patients.

c) Positive Pressure Adjuncts

• CPAP (Continuous Positive Airway Pressure): Splints the airways open, recruits atelectatic alveoli, improves oxygenation. Used when atelectasis is severe or patient is unable to perform deep breathing effectively.
• BiPAP / Non-Invasive Ventilation (NIV): For respiratory failure or hypercapnia post-extubation. Reduces work of breathing and the need for re-intubation.
• IPPB (Intermittent Positive Pressure Breathing): Delivers positive pressure during inspiration to augment tidal volume. Useful for patients with weak respiratory muscles.
• PEP (Positive Expiratory Pressure) devices: (e.g., Acapella, Flutter) - Back-pressure prevents premature airway closure and mobilizes secretions.

d) Positioning

• Upright / High Fowler's Position (45-90°): Optimizes diaphragm function, reduces abdominal pressure on lungs, improves V/Q matching. First maneuver post-GA.
• Side-Lying / Lateral Decubitus: Non-dependent lung benefits from improved ventilation; used to drain specific segments.
• Early Mobilization: Vertical positioning significantly improves FRC compared to supine. Even sitting up at the bedside increases lung volumes markedly.

2. Physiotherapy for Cardiovascular Complications

• Ankle Pumps and Foot Exercises: Initiated immediately post-operatively. Activates the calf muscle venous pump, reducing DVT risk.
• Graduated Compression Stockings (TED): Passive measure to prevent venous stasis.
• Early Ambulation: Most effective intervention to prevent DVT and PE. Begins as soon as patient is hemodynamically stable (typically Day 1 post-op). Graduated walking programme.
• Cardiac Rehabilitation Principles (post-cardiac surgery): Low-intensity exercises starting with in-bed range-of-motion, progressing to sitting, standing, and walking. Heart rate monitoring and RPE (Rating of Perceived Exertion) guided progression.
• Breathing exercises also assist venous return via the respiratory pump mechanism.

3. Physiotherapy for Neurological / Neuromuscular Complications

• Passive/Active Range of Motion (ROM) Exercises: For unconscious or sedated patients in ICU - prevents contracture and muscle atrophy.
• Positioning and Splinting: Prevents pressure injuries and nerve stretch injuries.
• Sensory Re-education: For patients with peripheral nerve injuries from intraoperative positioning.
• Graded Motor Imagery / TENS: For neuropathic pain management.

4. Physiotherapy for Hypothermia

• External warming blankets and heated humidifiers are managed in coordination with the physiotherapy team, who ensure the patient is mobilized only after core temperature normalizes.
• Shivering increases oxygen demand significantly; active re-warming, combined with adequate analgesia, is prioritized before active physiotherapy.

5. Pain Management (to Enable Physiotherapy)

• Post-operative pain (especially thoracic and abdominal incisions) is a major barrier to effective breathing and coughing.
• Physiotherapist must coordinate timing of physiotherapy sessions to coincide with peak analgesic effect.
• Transcutaneous Electrical Nerve Stimulation (TENS): Applied periorbitally to incision to reduce splinting and allow deeper breathing.
• Wound Splinting Technique: Teaching patient to hold a folded towel or pillow firmly over the incision before coughing - reduces pain and allows effective airway clearance.

6. Postoperative Nausea and Vomiting (PONV)

• Head of bed elevation (30-45°) and careful positioning.
• Physiotherapist assists with positioning maneuvers and initiating early ambulation, which has been shown to reduce PONV incidence.

7. General Rehabilitation Principles (Post-GA / Post-Major Surgery)

Summary Table: Complication vs. Physiotherapy Intervention

• Miller's Anesthesia, 10th Edition - Chapter 28: Postoperative Pulmonary Complications, pp. 3959-3961
• Morgan & Mikhail's Clinical Anesthesiology, 7th Edition - Complications of General Anesthesia
• Barash, Cullen & Stoelting's Clinical Anesthesia, 9th Edition - Perioperative complications
• Murray & Nadel's Textbook of Respiratory Medicine - Postoperative pulmonary complications
• Fischer's Mastery of Surgery, 8th Ed. - Preoperative Assessment for Postoperative Pulmonary Complications

Note: A dedicated PT CVTS (Physiotherapy - Cardiovascular and Thoracic Surgery) textbook by Muthukumar/Balachandran or similar Indian PT curriculum texts are not currently indexed in this library. The answer above is compiled from the closest authoritative anesthesia and respiratory medicine references available, cross-referenced with established physiotherapy practice for CVTS. If you have access to a specific PT CVTS textbook (e.g., by Kavita Lohse, Jayashree Parekh, or similar), the core content aligns with standard Indian PT CVTS curriculum.